Reproductive health financing in Kenya: an analysis of national commitments, donor assistance, and the resources tracking process.

PubMed

Sidze, Estelle M; Pradhan, Jalandhar; Beekink, Erik; Maina, Thomas M; Maina, Beatrice W

2013-11-01

Understanding the flow of resources at the country level to reproductive health is essential for effective financing of this key component of health. This paper gives a comprehensive picture of the allocation of resources for reproductive health in Kenya and the challenges faced in the resource-tracking process. Data are drawn from Kenyan budget estimates, reproductive health accounts, and the Resource Flows Project database and compare budgets and spending in 2005-06 with 2009-10. Despite policies and programmes in place since 1994, services for family planning, maternity care and infant and child health face serious challenges. As regards health financing, the government spends less than the average in sub-Saharan Africa, while donor assistance and out-of-pocket expenditure for health are high. Donor assistance to Kenya has increased over the years, but the percentage of funds devoted to reproductive health is lower than it was in 2005. We recommend an increase in the budget and spending for reproductive health in order to achieve MDG targets on maternal mortality and universal access to reproductive health in Kenya. Safety nets for the poor are also needed to reduce the burden of spending by households. Lastly, we recommend the generation of more comprehensive reproductive health accounts on a regular basis. Copyright © 2013 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.

Influence of long-distance seed dispersal on the genetic diversity of seed rain in fragmented Pinus densiflora populations relative to pollen-mediated gene flow.

PubMed

Ozawa, Hajime; Watanabe, Atsushi; Uchiyama, Kentaro; Saito, Yoko; Ide, Yuji

2013-01-01

Long-distance dispersal (LDD) of seeds has a critical impact on species survival in patchy landscapes. However, relative to pollen dispersal, empirical data on how seed LDD affects genetic diversity in fragmented populations have been poorly reported. Thus, we attempted to indirectly evaluate the influence of seed LDD by estimating maternal and paternal inbreeding in the seed rain of fragmented 8 Pinus densiflora populations. In total, the sample size was 458 seeds and 306 adult trees. Inbreeding was estimated by common parentage analysis to evaluate gene flow within populations and by sibship reconstruction analysis to estimate gene flow within and among populations. In the parentage analysis, the observed probability that sampled seeds had the same parents within populations was significantly larger than the expected probability in many populations. This result suggested that gene dispersal was limited to within populations. In the sibship reconstruction, many donors both within and among populations appeared to contribute to sampled seeds. Significant differences in sibling ratios were not detected between paternity and maternity. These results suggested that seed-mediated gene flow and pollen-mediated gene flow from outside population contributed some extent to high genetic diversity of the seed rain (H E > 0.854). We emphasize that pine seeds may have excellent potential for gene exchange within and among populations.

Systematic donor blood qualification by flow cytometry would have been able to avoid CLL-type MBL transmission after unrelated hematopoietic stem cell transplantation.

PubMed

Ferrand, Christophe; Garnache-Ottou, Francine; Collonge-Rame, Marie Agnès; Larosa, Fabrice; Blanc, Michel; Behar, Catherine; Giannoli, Catherine; Garnier, Frédérico; Tiberghien, Pierre; Deconinck, Eric; Rohrlich, Pierre Simon

2012-03-01

The current screening for eligibility of unrelated volunteer marrow donors comprises a complete clinical check-up, a blood CBC and serum protein immunoelectrophoresis. This allows to eliminate acute leukemias, myeloproliferative and myelodysplastic disorders, myelomas and MGUS. To date, the risk of transmission of chronic lymphocytic leukemia (CLL) disease is only evaluated by the clinical evaluation and CBC. We report here the case of a CLL-type MBL disease occurring in a 12-year-old boy after unrelated BMT. Deep biological investigations, as Immunophenotyping, cytogenetic and molecular biology allow us to determine the donor origin of the CLL clone. In 2010, 14.2% donor (105/737) for unrelated hematopoietic stem cell transplantation were over 45y. It is currently estimated (USA) that 1 in 210 men and women will be diagnosed with CLL during their lifetime. Given the long asymptomatic phase of CLL, this raises the case for a detection strategy analog to that used for MGUS and myeloma through serum protein electrophoresis. This case-report, to our knowledge, of a CLL-type MBL unrelated donor-to-recipient transmission through BMT raises ethical and practical questions, such as the proper information about disease transmission risk. The cost-effectiveness of a systematic peripheral blood Immunophenotyping in donors elder than 40y at time of stem cell donation should be evaluated. © 2012 John Wiley & Sons A/S.

Estimated Nephron Number of the Donor Kidney: Impact on Allograft Kidney Outcomes.

PubMed

Schachtner, T; Reinke, P

Low birth weights have been associated with a reduction in nephron number with compensatory hypertrophy of existing glomeruli. The impact of donor birth weight as an estimate of nephron number on allograft function, however, has not been examined. We collected donor birth weight, kidney weight, and volume from 91 living kidney donor-recipient pairs before nephrectomy and after 12, 36, and 60 months. Nephron number was calculated from donor birth weight and age. Donor birth weight, kidney weight/body surface area (BSA), and kidney volume showed a moderate positive correlation with allograft estimated glomerular filtration rate (eGFR) at 12 months (P < .05). Donor age showed a negative moderate correlation with allograft eGFR at 12 months (P = .015). The strongest correlation with allograft eGFR was observed for calculated donor kidney nephron number at 12, 36, and 60 months (R, 0.340, 0.305, and 0.476, respectively; P < .05). No impact was observed on allograft daily proteinuria of any investigated marker (P > .05). Recipients of donors with birth weight <2.5 kg had need of a significantly greater number of antihypertensive drugs (P < .05). Calculated nephron number from donor birth weight and age is suggested to be superior to donor kidney weight/BSA and volume regarding allograft function. Calculated nephron number could estimate expected eGFR and guide decision making in cases of impaired allograft function. Copyright © 2017 Elsevier Inc. All rights reserved.

Model swapping: A comparative performance signature for the prediction of flow duration curves in ungauged basins

NASA Astrophysics Data System (ADS)

Qamar, Muhammad Uzair; Azmat, Muhammad; Cheema, Muhammad Jehanzeb Masud; Shahid, Muhammad Adnan; Khushnood, Rao Arsalan; Ahmad, Sajjad

2016-10-01

The issue of lack of donor basins for prediction of flow duration curves (FDCs) in ungauged basins (PUB) is an important area of research that is not resolved in the literature. We present a distance based approach to predict FDCs at ungauged basins by quantifying the dissimilarity between FDCs and characteristics data of basins. This enables us to bracket hydrologically similar basins and thus allowing us to estimate FDCs at ungauged basins. Generally, a single regression model is selected to make hydrological estimates at an ungauged basin. Based on established laws and theories of hydrology, we work to devise a method to improve the output of selected model for an ungauged basin by swapping it with another model in case the latter gives better coverage and statistical estimates of the nearest neighbors of an ungauged basin. We report two examples to demonstrate the effectiveness of model swapping. Out of 124 basins used in analysis, 34 basins in example 1 and 41 basins in example 2 fulfill the set criteria of model swapping and subsequently their estimates are improved significantly.

Evaluation of the return rate of volunteer blood donors

PubMed Central

Lourençon, Adriana de Fátima; Almeida, Rodrigo Guimarães dos Santos; Ferreira, Oranice; Martinez, Edson Zangiacomi

2011-01-01

Background To convert first-time blood donors into regular volunteer donors is a challenge to transfusion services. Objectives This study aims to estimate the return rate of first time donors of the Ribeirão Preto Blood Center and of other blood centers in its coverage region. Methods The histories of 115,553 volunteer donors between 1996 and 2005 were analyzed. Statistical analysis was based on a parametric long-term survival model that allows an estimation of the proportion of donors who never return for further donations. Results Only 40% of individuals return within one year after the first donation and 53% return within two years. It is estimated that 30% never return to donate. Higher return rates were observed among Black donors. No significant difference was found in non-return rates regarding gender, blood type, Rh blood group and blood collection unit. Conclusions The low percentage of first-time donors who return for further blood donation reinforces the need for marketing actions and strategies aimed at increasing the return rates. PMID:23049294

Estimating the Number of Organ Donors in Australian Hospitals—Implications for Monitoring Organ Donation Practices

PubMed Central

Pilcher, David; Gladkis, Laura; Arcia, Byron; Bailey, Michael; Cook, David; Cass, Yael; Opdam, Helen

2015-01-01

Background The Australian DonateLife Audit captures information on all deaths which occur in emergency departments, intensive care units and in those recently discharged from intensive care unit. This information provides the opportunity to estimate the number of donors expected, given present consent rates and contemporary donation practices. This may then allow benchmarking of performance between hospitals and jurisdictions. Our aim was to develop a method to estimate the number of donors using data from the DonateLife Audit on the basis of baseline patient characteristics alone. Methods All intubated patient deaths at contributing hospitals were analyzed. Univariate comparisons of donors to nondonors were performed. A logistic regression model was developed to estimate expected donor numbers from data collected between July 2012 and December 2013. This was validated using data from January to April 2014. Results Between July 2012 and April 2014, 6861 intubated patient deaths at 68 hospitals were listed on the DonateLife Audit of whom 553 (8.1%) were organ donors. Factors independently associated with organ donation included age, brain death, neurological diagnoses, chest x-ray findings, PaO2/FiO2, creatinine, alanine transaminase, cancer, cardiac arrest, chronic heart disease, and peripheral vascular disease. A highly discriminatory (area under the receiver operatory characteristic, 0.940 [95% confidence interval, 0.924-0.957]) and well-calibrated prediction model was developed which accurately estimated donor numbers. Three hospitals appeared to have higher numbers of actual donors than expected. Conclusions It is possible to estimate the expected number of organ donors. This may assist benchmarking of donation outcomes and interpretation of changes in donation rates over time. PMID:25919766

Risk appreciation for living kidney donors: another new subspecialty?

PubMed

Steiner, Robert W

2004-05-01

Quantitative estimates of the risk of end stage renal disease (ESRD) for living donors would seem essential to defensible donor selection practices, as the 'safe/unsafe' model for donor selection is not viable. All kidney donors take risk, and four fundamental, qualitative criteria should instead be used to decide when donor rejection is justified. These criteria are lack of donor education about transplantation, donor irrationality, lack of free and voluntary donation, and/or that donor acceptance would unavoidably threaten the public trust or the integrity of the center's selection procedures. Such a data-based selection policy, with explicit documentation of unbiased and comprehensive donor education, will help neutralize the center's self interest in a more defensible way than by rejecting 'complicated' kidney donors out of hand, and in a more practical way than by the creation of center-independent donor counselors or waiting for donor registries to come to fruition. Living kidney donors with isolated medical abnormalities comprise a sizable subset of at risk donors for whom center acceptance practices vary markedly. This population provides a paradigm opportunity for quantitative risk estimation and counseling.

A Kidney Graft Survival Calculator that Accounts for Mismatches in Age, Sex, HLA, and Body Size.

PubMed

Ashby, Valarie B; Leichtman, Alan B; Rees, Michael A; Song, Peter X-K; Bray, Mathieu; Wang, Wen; Kalbfleisch, John D

2017-07-07

Outcomes for transplants from living unrelated donors are of particular interest in kidney paired donation (KPD) programs where exchanges can be arranged between incompatible donor-recipient pairs or chains created from nondirected/altruistic donors. Using Scientific Registry of Transplant Recipients data, we analyzed 232,705 recipients of kidney-alone transplants from 1998 to 2012. Graft failure rates were estimated using Cox models for recipients of kidney transplants from living unrelated, living related, and deceased donors. Models were adjusted for year of transplant and donor and recipient characteristics, with particular attention to mismatches in age, sex, human leukocyte antigens (HLA), body size, and weight. The dependence of graft failure on increasing donor age was less pronounced for living-donor than for deceased-donor transplants. Male donor-to-male recipient transplants had lower graft failure, particularly better than female to male (5%-13% lower risk). HLA mismatch was important in all donor types. Obesity of both the recipient (8%-18% higher risk) and donor (5%-11% higher risk) was associated with higher graft loss, as were donor-recipient weight ratios of <75%, compared with transplants where both parties were of similar weight (9%-12% higher risk). These models are used to create a calculator of estimated graft survival for living donors. This calculator provides useful information to donors, candidates, and physicians of estimated outcomes and potentially in allowing candidates to choose among several living donors. It may also help inform candidates with compatible donors on the advisability of joining a KPD program. Copyright © 2017 by the American Society of Nephrology.

The potential supply of organ donors. An assessment of the efficacy of organ procurement efforts in the United States.

PubMed

Evans, R W; Orians, C E; Ascher, N L

1992-01-08

To estimate the potential supply of organ donors and to measure the efficiency of organ procurement efforts in the United States. A geographic database has been developed consisting of multiple cause of death and sociodemographic data compiled by the National Center for Health Statistics. All deaths are evaluated as to their potential for organ donation. Two classes of potential donors are identified: class 1 estimates are restricted to causes of death involving significant head trauma only, and class 2 estimates include class 1 estimates as well as deaths in which brain death was less probable. Over 23,000 people are currently awaiting a kidney, heart, liver, heart-lung, pancreas, or lung transplantation. Donor supply is inadequate, and the number of donors remained unchanged at approximately 4000 annually for 1986 through 1989, with a modest 9.1% increase in 1990. Between 6900 and 10,700 potential donors are available annually (eg, 28.5 to 43.7 per million population). Depending on the class of donor considered, organ procurement efforts are between 37% and 59% efficient. Efficiency greatly varies by state and organ procurement organization. Many more organ donors are available than are being accessed through existing organ procurement efforts. Realistically, it may be possible to increase by 80% the number of donors available in the United States (up to 7300 annually). It is conceivable, although unlikely, that the supply of donor organs could achieve a level to meet demand.

Dark current of organic heterostructure devices with insulating spacer layers

NASA Astrophysics Data System (ADS)

Yin, Sun; Nie, Wanyi; Mohite, Aditya D.; Saxena, Avadh; Smith, Darryl L.; Ruden, P. Paul

2015-03-01

The dark current density at fixed voltage bias in donor/acceptor organic planar heterostructure devices can either increase or decrease when an insulating spacer layer is added between the donor and acceptor layers. The dominant current flow process in these systems involves the formation and subsequent recombination of an interfacial exciplex state. If the exciplex formation rate limits current flow, the insulating interface layer can increase dark current whereas, if the exciplex recombination rate limits current flow, the insulating interface layer decreases dark current. We present a device model to describe this behavior and illustrate it experimentally for various donor/acceptor systems, e.g. P3HT/LiF/C60.

The Benefit of Donor-Recipient Matching for Patients Undergoing Heart Transplantation.

PubMed

Nguyen, Vidang P; Mahr, Claudius; Mokadam, Nahush A; Pal, Jay; Smith, Jason W; Dardas, Todd F

2017-04-04

Heart transplant volumes are not matching growing demand, and donor heart use may be decreasing. This study sought to investigate the benefit of heart transplantation compared with waiting while accounting for the estimated risk of a given donor-recipient match. This study identified 28,548 heart transplant candidates in the Organ Procurement and Transplant Network between July 2006 and December 2015. Donor-recipient match quality was estimated from the donor risk index. A time-dependent covariate Cox model was used to determine the effect of donor-recipient match quality on the likelihood of a composite outcome while waiting for a transplant or after transplantation. The composite outcome was death or delisting as too ill. Donor and recipient risk estimates were inversely related to the candidate urgency. Net benefit from heart transplantation was evident across all estimates of donor-recipient status 1A and 1B candidates: status 1A (lowest-risk quartile hazard ratio [HR]: 0.37; 95% confidence interval [CI]: 0.31 to 0.43; highest-risk quartile HR: 0.52; 95% CI: 0.44 to 0.61) and status 1B candidates (lowest-risk quartile HR: 0.41; 95% CI: 0.36 to 0.47; highest-risk quartile HR: 0.66; 95% CI: 0.58 to 0.74). Status 2 candidates showed a benefit from heart transplantation; however, survival benefit was delayed. For the highest-risk donor-recipient matches, a net benefit of transplantation occurred immediately for status 1A candidates, after 12 months for status 1B candidates, and after 3 years for status 2 candidates. This study demonstrated a survival benefit of heart transplantation across all ranges of estimated donor-recipient match risk for status 1A and status 1B candidates. Donor heart acceptance should be the favored strategy for these candidates. The benefit of transplantation for status 2 candidates was less apparent and dependent on estimated donor-recipient match risk, suggesting that a measure of donor-recipient match quality may be useful when considering the immediate benefit of heart transplantation for status 2 candidates in stable condition. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Quantification of body iron and iron absorption in the REDS-II Donor Iron Status Evaluation (RISE) study.

PubMed

Kiss, Joseph E; Birch, Rebecca J; Steele, Whitney R; Wright, David J; Cable, Ritchard G

2017-07-01

Repeated blood donation alters the iron balance of blood donors. We quantified these effects by analyzing changes in body iron as well as calculating iron absorbed per day for donors enrolled in a prospective study. For 1308 donors who completed a final study visit, we calculated total body iron at the enrollment and final visits and the change in total body iron over the course of the study. Taking into account iron lost from blood donations during the study and obligate losses, we also calculated the average amount of iron absorbed per day. First-time/reactivated donors at enrollment had iron stores comparable to previous general population estimates. Repeat donors had greater donation intensity and greater mean iron losses than first-time/reactivated donors, yet they had little change in total body iron over the study period, whereas first-time/reactivated donors had an average 35% drop. There was higher estimated iron absorption in the repeat donors (men: 4.49 mg/day [95% confidence interval [CI], 4.41-4.58 mg/day]; women: 3.75 mg/day [95% CI, 3.67-3.84 mg/day]) compared with estimated iron absorption in first-time/reactivated donors (men: 2.89 mg/day [95% CI, 2.75-3.04 mg/day]; women: 2.76 mg/day [95% CI, 2.64-2.87 mg/day]). The threshold for negative estimated iron stores (below "0" mg/kg stores) was correlated with the development of anemia at a plasma ferritin value of 10 ng/mL. These analyses provide quantitative data on changes in estimated total body iron for a broad spectrum of blood donors. In contrast to using ferritin alone, this model allows assessment of the iron content of red blood cells and the degree of both iron surplus and depletion over time. © 2017 AABB.

Determination of Acceptor Concentration, Depletion Width, Donor Level Movement and Sensitivity Factor of ZnO on Diamond Heterojunction under UV Illumination

PubMed Central

Saw, Kim Guan; Tneh, Sau Siong; Yam, Fong Kwong; Ng, Sha Shiong; Hassan, Zainuriah

2014-01-01

The concentration of acceptor carriers, depletion width, magnitude of donor level movement as well as the sensitivity factor are determined from the UV response of a heterojunction consisting of ZnO on type IIb diamond. From the comparison of the I-V measurements in dark condition and under UV illumination we show that the acceptor concentration (∼1017 cm−3) can be estimated from p-n junction properties. The depletion width of the heterojunction is calculated and is shown to extend farther into the ZnO region in dark condition. Under UV illumination, the depletion width shrinks but penetrates both materials equally. The ultraviolet illumination causes the donor level to move closer to the conduction band by about 50 meV suggesting that band bending is reduced to allow more electrons to flow from the intrinsically n-type ZnO. The sensitivity factor of the device calculated from the change of threshold voltages, the ratio of dark and photocurrents and identity factor is consistent with experimental data. PMID:24586707

The Natural History of Kidney Graft Cortical Microcirculation Determined by Real-Time Contrast-Enhanced Sonography (RT-CES).

PubMed

Jiménez, Carlos; López, María Ovidia; Ros, Amaia; Aguilar, Ana; Menendez, David; Rivas, Begoña; Santana, María José; Vaca, Marco Antonio; Escuin, Fernando; Madero, Rosario; Selgas, Rafael

2016-01-01

Kidney transplantation is the therapy of choice for end-stage kidney disease. Graft's life span is shorter than expected due in part to the delayed diagnosis of various complications, specifically those related to silent progression. It is recognized that serum creatinine levels and proteinuria are poor markers of mild kidney lesions, which results in delayed clinical information. There are many investigation looking for early markers of graft damage. Decreasing kidney graft cortical microcirculation has been related to poor prognosis in kidney transplantation. Cortical capillary blood flow (CCBF) can be measured by real-time contrast-enhanced sonography (RT-CES). Our aim was to describe the natural history of CCBF over time under diverse conditions of kidney transplantation, to explore the influence of donor conditions and recipient events, and to determine the capacity of CCBF for predicting renal function in medium term. RT-CES was performed in 79 consecutive kidney transplant recipients during the first year under regular clinical practice. Cortical capillary blood flow was measured. Clinical variables were analyzed. The influence of CCBF has been determined by univariate and multivariate analysis using mixed regression models based on sequential measurements for each patient over time. We used a first-order autoregression model as the structure of the covariation between measures. The post-hoc comparisons were considered using the Bonferroni correction. The CCBF values varied significantly over the study periods and were significantly lower at 48 h and day 7. Brain-death donor age and CCBF levels showed an inverse relationship (r: -0.62, p<0.001). Living donors showed higher mean CCBF levels than brain-death donors at each point in the study. These significant differences persisted at month 12 (54.5 ± 28.2 vs 33.7 ± 30 dB/sec, living vs brain-death donor, respectively, p = 0.004) despite similar serum creatinine levels (1.5 ± 0.3 and 1.5 ± 0.5 mg/dL). A sole rejection episode was associated with lower overall CCBF values over the first year. CCBF defined better than level of serum creatinine the graft function status at medium-term. RT-CES is a non-invasive tool that can quantify and iteratively estimate cortical microcirculation. We have described the natural history of cortical capillary blood flow under regular clinical conditions.

CT-based renal volume and graft function after living-donor kidney transplantation: Is there a volume threshold to avoid?

PubMed

Dias, Jorge; Malheiro, Jorge; Almeida, Manuela; Dias, Leonídio; Silva-Ramos, Miguel; Martins, La Salete; Xambre, Luís; Castro-Henriques, António

2015-05-01

Donated kidney volume influences post-transplant outcomes and graft survival. We evaluated the relationship between living-donor kidney volume and recipient graft function at 12 months post-transplantation, exploring a volume threshold for a suboptimal graft function, and compared two different formulas of volume estimation. A retrospective analysis of 82 pairs of living-donor kidney transplants was conducted. Donor renal volumes were estimated from computerized tomography scans using the ellipsoid formula and the voxel counting technique. Linear and restricted cubic regression spline was used to analyze the association of volume with graft function. Additionally, we determined the correlation between the two volume estimation formulas and established a correction factor for the ellipsoid formula. Renal volume (adjusted to recipient BSA) had the strongest independent effect (B = 1.65 per 10 ml/m(2) increase, p value <0.001) on graft function at 12 months. The eGFR at 12 months was 52.5, 63.6 and 67.6 ml/min/1.73 m(2) for the low, medium and high volume ratio terciles, respectively (p value <0.001). The odds of a GFR <50 ml/min became significantly reduced with volumes above 145 cc/1.73 m(2). A strong positive correlation between the two formulas was identified (R(2) = 0.705), but the optimal correction factor for our cohort was 0.566. In a Caucasian population, higher donor kidney volumes estimated from preoperative CT scans are associated with higher recipient eGFRs at 12 months after live-donor transplantation. Using this criterion, transplant teams can potentially improve selection of living donors if multiple donors are available. However, the need for precise estimation of donor kidney volumes should not be overlooked.

Understanding noncompliance with selective donor deferral criteria for high-risk behaviors in Australian blood donors.

PubMed

Lucky, Tarana T A; Seed, Clive R; Waller, Daniel; Lee, June F; McDonald, Ann; Wand, Handan; Wroth, Stephen; Shuttleworth, Glen; Keller, Anthony J; Pink, Joanne; Wilson, David P

2014-07-01

Using a predonation screening questionnaire, potential blood donors are screened for medical or behavioral factors associated with an increased risk for transfusion-transmissible infection. After disclosure of these risks, potential donors are deferred from donating. Understanding the degree of failure to disclose full and truthful information (termed noncompliance) is important to determine and minimize residual risk. This study estimates the prevalence of, and likely reasons for, noncompliance among Australian donors with the deferrals for injecting drug use, sex with an injecting drug user, male-to-male sex, sex worker activity or contact, and sex with a partner from a high-HIV-prevalence country. An anonymous, online survey of a nationally representative sample of Australian blood donors was conducted. Prevalence of noncompliance with deferrable risk categories was estimated. Factors associated with noncompliance were determined using unadjusted and adjusted odds ratios. Of 98,044 invited donors, 30,790 donors completed the survey. The estimated prevalence of overall noncompliance (i.e., to at least one screening question) was 1.65% (95% confidence interval CI, 1.51%-1.8%). Noncompliance with individual deferrals ranged from 0.05% (sex work) to 0.54% (sex with an injecting drug user). The prevalences of the disclosed exclusionary risk behaviors were three to 14 times lower than their estimated prevalence in the general population. The prevalence of noncompliance is relatively low but our estimate is likely to be a lower bound. The selected high-risk behaviors were substantially less common in blood donors compared to the general population suggesting that self-deferral is effective. Nevertheless, a focus on further minimization should improve the blood safety. © 2014 AABB.

Synthesis of Donor/Acceptor-Substituted Diazo Compounds in Flow and Their Application in Enantioselective Dirhodium-Catalyzed Cyclopropanation and C-H Functionalization.

PubMed

Rackl, Daniel; Yoo, Chun-Jae; Jones, Christopher W; Davies, Huw M L

2017-06-16

A tandem reaction system has been developed for the preparation of donor/acceptor-substituted diazo compounds in continuous flow coupled to dirhodium-catalyzed C-H functionalization or cyclopropanation. Hydrazones were oxidized in flow by solid-supported N-iodo-p-toluenesulfonamide potassium salt (PS-SO 2 NIK) to generate the diazo compounds, which were then purified by passing through a column of molecular sieves/sodium thiosulfate.

The heterogeneous HLA genetic makeup of the Swiss population.

PubMed

Buhler, Stéphane; Nunes, José Manuel; Nicoloso, Grazia; Tiercy, Jean-Marie; Sanchez-Mazas, Alicia

2012-01-01

This study aims at investigating the HLA molecular variation across Switzerland in order to determine possible regional differences, which would be highly relevant to several purposes: optimizing donor recruitment strategies in hematopoietic stem cell transplantation (HSCT), providing reliable reference data in HLA and disease association studies, and understanding the population genetic background(s) of this culturally heterogeneous country. HLA molecular data of more than 20,000 HSCT donors from 9-13 recruitment centers of the whole country were analyzed. Allele and haplotype frequencies were estimated by using new computer tools adapted to the heterogeneity and ambiguity of the data. Non-parametric and resampling statistical tests were performed to assess Hardy-Weinberg equilibrium, selective neutrality and linkage disequilibrium among different loci, both in each recruitment center and in the whole national registry. Genetic variation was explored through genetic distance and hierarchical analysis of variance taking into account both geographic and linguistic subdivisions in Switzerland. The results indicate a heterogeneous genetic makeup of the Swiss population: first, allele frequencies estimated on the whole national registry strongly deviate from Hardy-Weinberg equilibrium, by contrast with the results obtained for individual centers; second, a pronounced differentiation is observed for Ticino, Graubünden, and, to a lesser extent, Wallis, suggesting that the Alps represent(ed) a barrier to gene flow; finally, although cultural (linguistic) boundaries do not represent a main genetic differentiation factor in Switzerland, the genetic relatedness between population from south-eastern Switzerland and Italy agrees with historical and linguistic data. Overall, this study justifies the maintenance of a decentralized donor recruitment structure in Switzerland allowing increasing the genetic diversity of the national--and hence global--donor registry. It also indicates that HLA data of local donor recruitment centers can be used as reference data in both epidemiological and population genetic studies focusing on the genetic history of present European populations.

The Heterogeneous HLA Genetic Makeup of the Swiss Population

PubMed Central

Buhler, Stéphane; Nunes, José Manuel; Nicoloso, Grazia; Tiercy, Jean-Marie; Sanchez-Mazas, Alicia

2012-01-01

This study aims at investigating the HLA molecular variation across Switzerland in order to determine possible regional differences, which would be highly relevant to several purposes: optimizing donor recruitment strategies in hematopoietic stem cell transplantation (HSCT), providing reliable reference data in HLA and disease association studies, and understanding the population genetic background(s) of this culturally heterogeneous country. HLA molecular data of more than 20,000 HSCT donors from 9–13 recruitment centers of the whole country were analyzed. Allele and haplotype frequencies were estimated by using new computer tools adapted to the heterogeneity and ambiguity of the data. Non-parametric and resampling statistical tests were performed to assess Hardy-Weinberg equilibrium, selective neutrality and linkage disequilibrium among different loci, both in each recruitment center and in the whole national registry. Genetic variation was explored through genetic distance and hierarchical analysis of variance taking into account both geographic and linguistic subdivisions in Switzerland. The results indicate a heterogeneous genetic makeup of the Swiss population: first, allele frequencies estimated on the whole national registry strongly deviate from Hardy-Weinberg equilibrium, by contrast with the results obtained for individual centers; second, a pronounced differentiation is observed for Ticino, Graubünden, and, to a lesser extent, Wallis, suggesting that the Alps represent(ed) a barrier to gene flow; finally, although cultural (linguistic) boundaries do not represent a main genetic differentiation factor in Switzerland, the genetic relatedness between population from south-eastern Switzerland and Italy agrees with historical and linguistic data. Overall, this study justifies the maintenance of a decentralized donor recruitment structure in Switzerland allowing increasing the genetic diversity of the national—and hence global—donor registry. It also indicates that HLA data of local donor recruitment centers can be used as reference data in both epidemiological and population genetic studies focusing on the genetic history of present European populations. PMID:22848484

Hepatic Hemodynamics and Portal Flow Modulation: The A2ALL Experience.

PubMed

Emond, Jean C; Goodrich, Nathan P; Pomposelli, James J; Baker, Talia B; Humar, Abhinav; Grant, David R; Abt, Peter; Friese, Chris E; Fisher, Robert A; Kam, Igal; Sherker, Averell H; Gillespie, Brenda W; Merion, Robert M

2017-10-01

A principal aim of the Adult-to-Adult Living Donor Liver Transplantation Cohort Study was to study hepatic blood flow and effect of portal flow modulation on graft outcomes in the setting of increasing use of smaller and left lobe grafts. Recipients of 274 living donor liver transplant were enrolled in the Adult-to-Adult Living Donor Liver Transplantation Cohort Study, including 233 (85.0%) right lobes, 40 (14.6%) left lobes, and 1 (0.5%) left lateral section. Hepatic hemodynamics were recorded after reperfusion. A total of 57 portal flow modulations were performed on 52 subjects. Modulation lowered portal pressure in 68% of subjects with inconsistent effects on hepatic arterial and portal flow. A higher rate of graft dysfunction was observed in modulated vs. unmodulated subjects (31% vs. 18%; P = 0.03); however, graft survival in modulated subjects was not different from unmodulated subjects at 3 years. These results suggest the need for a study using a prespecified portal flow modulation protocol with defined indications to better define the effects of these interventions.

Interface Si donor control to improve dynamic performance of AlGaN/GaN MIS-HEMTs

NASA Astrophysics Data System (ADS)

Song, Liang; Fu, Kai; Zhang, Zhili; Sun, Shichuang; Li, Weiyi; Yu, Guohao; Hao, Ronghui; Fan, Yaming; Shi, Wenhua; Cai, Yong; Zhang, Baoshun

2017-12-01

In this letter, we have studied the performance of AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) with different interface Si donor incorporation which is tuned during the deposition process of LPCVD-SiNx which is adopted as gate dielectric and passivation layer. Current collapse of the MIS-HEMTs without field plate is suppressed more effectively by increasing the SiH2Cl2/NH3 flow ratio and the normalized dynamic on-resistance (RON) is reduced two orders magnitude after off-state VDS stress of 600 V for 10 ms. Through interface characterization, we have found that the interface deep-level traps distribution with high Si donor incorporation by increasing the SiH2Cl2/NH3 flow ratio is lowered. It's indicated that the Si donors are most likely to fill and screen the deep-level traps at the interface resulting in the suppression of slow trapping process and the virtual gate effect. Although the Si donor incorporation brings about the increase of gate leakage current (IGS), no clear degradation of breakdown voltage can be seen by choosing appropriate SiH2Cl2/NH3 flow ratio.

Maximum number of children per sperm donor based on false paternity rate.

PubMed

Sánchez-Castelló, Isabel M; Gonzalvo, María C; Clavero, Ana; López-Regalado, María L; Mozas, Juan; Martínez-Granados, Luis; Navas, Purificación; Castilla, José A

2017-03-01

The aim of this study is to estimate the weight of each relevant factor in such unions of inadvertent consanguinity and to determine a "reasonable" limit for the number of children per donor, matching the probability of inadvertent consanguinity arising from the use of sperm donor in assisted reproduction with that of such a union arising from false paternity. In this study, we applied to Spanish data a mathematical model of consanguineous unions, taking into account the following factors: maximum number of live births/donor, fertility rate, average number of births per donor in a pregnancy, donor success rate, matings per phenotype, number of newborns/year, and number of donors needed in the population/year and births by false paternity. In Spain, the number of inadvertent unions between descendants of the same donor in Spain has been estimated at 0.4/year (one every two and a half years), although this frequency decreases as the reference population increases. On the other hand, the frequency of unions between family members due to false paternity has been estimated at 6.1/year. Thus, only 6% of such unions are due to the use of donor sperm. A total of 25 children per sperm donor are needed to align the probability of inadvertant consanguinity arising from the use of assisted reproduction with that due to false paternity. Therefore, we consider this number to be the maximum "reasonable" number of children born per donor in Spain.

Far-Zone Resonant Energy Transfer in X-ray Photoemission as a Structure Determination Tool.

PubMed

Céolin, Denis; Rueff, Jean-Pascal; Zimin, Andrey; Morin, Paul; Kimberg, Victor; Polyutov, Sergey; Ågren, Hans; Gel'mukhanov, Faris

2017-06-15

Near-zone Förster resonant energy transfer is the main effect responsible for excitation energy flow in the optical region and is frequently used to obtain structural information. In the hard X-ray region, the Förster law is inadequate because the wavelength is generally shorter than the distance between donors and acceptors; hence, far-zone resonant energy transfer (FZRET) becomes dominant. We demonstrate the characteristics of X-ray FZRET and its fundamental differences with the ordinary near-zone resonant energy-transfer process in the optical region by recording and analyzing two qualitatively different systems: high-density CuO polycrystalline powder and SF 6 diluted gas. We suggest a method to estimate geometrical structure using X-ray FZRET employing as a ruler the distance-dependent shift of the acceptor core ionization potential induced by the Coulomb field of the core-ionized donor.

China's role as a global health donor in Africa: what can we learn from studying under reported resource flows?

PubMed

Grépin, Karen A; Fan, Victoria Y; Shen, Gordon C; Chen, Lucy

2014-12-30

There is a growing recognition of China's role as a global health donor, in particular in Africa, but there have been few systematic studies of the level, destination, trends, or composition of these development finance flows or a comparison of China's engagement as a donor with that of more traditional global health donors. Using newly released data from AidData on China's development finance activities in Africa, developed to track under reported resource flows, we identified 255 health, population, water, and sanitation (HPWS) projects from 2000-2012, which we descriptively analyze by activity sector, recipient country, project type, and planned activity. We compare China's activities to projects from traditional donors using data from the OECD's Development Assistance Committee (DAC) Creditor Reporting System. Since 2000, China increased the number of HPWS projects it supported in Africa and health has increased as a development priority for China. China's contributions are large, ranking it among the top 10 bilateral global health donors to Africa. Over 50% of the HPWS projects target infrastructure, 40% target human resource development, and the provision of equipment and drugs is also common. Malaria is an important disease priority but HIV is not. We find little evidence that China targets health aid preferentially to natural resource rich countries. China is an important global health donor to Africa but contrasts with traditional DAC donors through China's focus on health system inputs and on malaria. Although better data are needed, particularly through more transparent aid data reporting across ministries and agencies, China's approach to South-South cooperation represents an important and distinct source of financial assistance for health in Africa.

Pathologic Criteria to Estimate the State of the Liver in Potential Donors.

PubMed

Shaimardanova, Caliya; Fedotovskikh, Galina; Savchuk, Aleksandr; Doszhan, Ainura; Smagulova, Aigerim; Gaipov, Abduzhappar

2015-11-01

The pathologic evaluation of the liver is one of the most important issues in liver transplants. We evaluated the histopathological condition of livers in potential donors. After liver biopsy, 37 potential donor livers were histologically studied. Liver tissue was stained by hematoxylin and eosin as well as Masson Trichrome. The results of the study showed the morphologic criteria used to estimate the state of the liver in potential donors is not only steatosis and fibrosis, but other important histologic criteria, such as proteinosis, necrosis of hepatocytes, endotheliitis of central veins, inflammatory infiltration, endarteritis in portal tracts and phlebitis in portal tracts, proliferation of the bile ducts, and cholestasis. Results of the study showed that the morphologic criteria to estimate the state of the liver in potential donors includes not only steatosis and fibrosis, but other important histologic criteria as well.

Tax economics of charitable giving: pointers for the hospital and donor.

PubMed

1980-01-01

Charitable giving is a big business in the United States. In 1979 over $43 billion was donated to charitable organizations, an amount equal to over 50 percent of the $78 billion combined net income for all of Fortune Magazine's largest 500 corporations in America. Only 13.7 percent (approximately $6 billion) of these donations were received by health care institutions. A much smaller amount went specifically to hospitals. The excalating cost of providing quality health care and the increasing difficulty of fully recovering these costs from third party payers is making hospitals more dependent on charitable contributions to remain solvent. Hospital executives and board members who can intelligently discuss with potential donors the tax economics of charitable giving are better able to increase the flow of donated funds to their own hospitals. Careful planning by donors and hospitals can result in properly structured donations that reduce taxes paid by the donor, increase the donor's personal cash flow and increase donations to the hospital.

A novel tool for high-throughput screening of granulocyte-specific antibodies using the automated flow cytometric granulocyte immunofluorescence test (Flow-GIFT).

PubMed

Nguyen, Xuan Duc; Dengler, Thomas; Schulz-Linkholt, Monika; Klüter, Harald

2011-02-03

Transfusion-related acute lung injury (TRALI) is a severe complication related with blood transfusion. TRALI has usually been associated with antibodies against leukocytes. The flow cytometric granulocyte immunofluorescence test (Flow-GIFT) has been introduced for routine use when investigating patients and healthy blood donors. Here we describe a novel tool in the automation of the Flow-GIFT that enables a rapid screening of blood donations. We analyzed 440 sera from healthy female blood donors for the presence of granulocyte antibodies. As positive controls, 12 sera with known antibodies against anti-HNA-1a, -b, -2a; and -3a were additionally investigated. Whole-blood samples from HNA-typed donors were collected and the test cells isolated using cell sedimentation in a Ficoll density gradient. Subsequently, leukocytes were incubated with the respective serum and binding of antibodies was detected using FITC-conjugated antihuman antibody. 7-AAD was used to exclude dead cells. Pipetting steps were automated using the Biomek NXp Multichannel Automation Workstation. All samples were prepared in the 96-deep well plates and analyzed by flow cytometry. The standard granulocyte immunofluorescence test (GIFT) and granulocyte agglutination test (GAT) were also performed as reference methods. Sixteen sera were positive in the automated Flow-GIFT, while five of these sera were negative in the standard GIFT (anti-HNA 3a, n = 3; anti-HNA-1b, n = 1) and GAT (anti-HNA-2a, n = 1). The automated Flow-GIFT was able to detect all granulocyte antibodies, which could be only detected in GIFT in combination with GAT. In serial dilution tests, the automated Flow-GIFT detected the antibodies at higher dilutions than the reference methods GIFT and GAT. The Flow-GIFT proved to be feasible for automation. This novel high-throughput system allows an effective antigranulocyte antibody detection in a large donor population in order to prevent TRALI due to transfusion of blood products.

Donating Blood

MedlinePlus

... someone you know will need a blood transfusion. Blood donors — especially donors with certain blood types — are always ... The Red Cross estimates that 15% of all blood donors in the United States are high school or ...

Successful ABO-Incompatible Renal Transplantation:  Blood Group A1B Donor Into A2B Recipient With Anti-A1 Isoagglutinins.

PubMed

Fadeyi, Emmanuel A; Stratta, Robert J; Farney, Alan C; Pomper, Gregory J

2016-08-01

Transplantation of the blood group A2B in a recipient was successfully performed in the setting of receiving a deceased donor kidney from an "incompatible" A1B donor. The donor and recipient were both typed for ABO blood group, including ABO genotyping. The donor and recipient were tested for ABO, non-ABO, and human leukocyte antigen (HLA) antibodies. The donor and recipient were typed for HLA antigens, including T- and B-flow cytometry crossmatch tests. The recipient's RBCs were negative with A1 lectin, and immunoglobulin G anti-A1 was demonstrated in the recipient's plasma. The donor-recipient pair was a four-antigen HLA mismatch, but final T- and B-flow cytometry crossmatch tests were compatible. The transplant procedure was uneventful; the patient experienced immediate graft function with no episodes of rejection or readmissions more than 2 years later. It may be safe to transplant across the A1/A2 blood group AB mismatch barrier in the setting of low titer anti-A1 isoagglutinins without the need for pretransplant desensitization even if the antibody produced reacts with anti-human globulin. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Using ultrasonography to monitor liver blood flow for liver transplant from donors supported on extracorporeal membrane oxygenation.

PubMed

Zhu, Xian-Sheng; Wang, Sha-Sha; Cheng, Qi; Ye, Chuang-Wen; Huo, Feng; Li, Peng

2016-02-01

Extracorporeal membrane oxygenation (ECMO) has been used to support brain-dead donors for liver procurement. This study investigated the potential role of ultrasonographic monitoring of hepatic perfusion as an aid to improve the viability of liver transplants obtained from brain-dead donors who are supported on ECMO. A total of 40 brain-dead patients maintained on ECMO served as the study population. Hepatic blood flow was monitored using ultrasonography, and perioperative optimal perfusion was maintained by calibrating ECMO. Liver function tests were performed to assess the viability of the graft. The hepatic arterial blood flow was well maintained with no significant changes observed before and after ECMO (206 ± 32 versus 241 ± 45 mL/minute; P = 0.06). Similarly, the portal venous blood flow was also maintained throughout (451 ± 65 versus 482 ± 77 mL/minute; P = 0.09). No significant change in levels of total bilirubin, alanine transaminase, and lactic acid were reported during ECMO (P = 0.17, P = 0.08, and P = 0.09, respectively). Before the liver is procured, ultrasonographic monitoring of hepatic blood flow could be a valuable aid to improve the viability of a liver transplant by allowing for real-time calibration of ECMO perfusion in brain-dead liver donors. In our study, ultrasonographic monitoring helped prevent warm ischemic injury to the liver graft by avoiding both overperfusion and underperfusion of the liver. © 2015 American Association for the Study of Liver Diseases.

Using EasyMatch® to anticipate the identification of an HLA identical unrelated donor: A validated efficient time and cost saving method.

PubMed

Dubois, Valérie; Detrait, Marie; Sobh, Mohamad; Morisset, Stéphane; Labussière, Hélène; Giannoli, Catherine; Nicolini, Franck; Moskovtchenko, Philippe; Mialou, Valérie; Ducastelle, Sophie; Rey, Sylvie; Thomas, Xavier; Barraco, Fiorenza; Tedone, Nathalie; Marry, Evelyne; Garnier, Federico; Bertrand, Yves; Michallet, Mauricette

2016-11-01

In the absence of an HLA matched familial donor, a search for an unrelated donor or cord blood unit is initiated through worldwide registries. Although a first look-up on available HLA information of donors in the "book" at BMDW (Bone Marrow Donor Worldwide) can provide a good estimation of the number of compatible donors, the variety of resolution typing levels requires confirmatory typing (CT) which are expensive and time consuming. In order to help recipient centers in their work. The French donor registry (France Greffe de Moelle/Agence de la Biomedecine) has recently developed a software program called "EasyMatch®" that uses haplotype frequencies to compute the likelihood of phenotypic match in donors according to various typing resolution levels. The goal of our study is to report a single monocentric user-experience with EasyMatch®, demonstrating that its routine use reduced the cost and the delay of the donor search in our center, allowing the definition of a new strategy to search compatible unrelated donors. The strategy was first established on a retrospective cohort of 217 recipients (185 adults and 32 children=before score) and then validated on a prospective cohort of 171 recipients (160 adults and 11 children=after score). For all patients, we calculated the delay between the registration day and the donor identification day, and the number of CT requested to the donor centre. Considering both groups, we could observe a significant decrease of the number of CT from 8 to 2 (p<0,001), and a significant decrease of the median delay to identify a suitable donor from 43 to 31days (p<0.0001). EasyMatch® estimates the number of potentially identical donors, but doesn't foresee availability of the donors. It provides us an easy tracking of mismatches, an estimation of the number of potential donors, the selection of population following ethnic origin of patients and a high prediction when probability is high or low. It affords a new approach of donor search in our daily work and improves the efficiency in the great challenge of the compatible donor identification. Copyright © 2016 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

A New Approximate Chimera Donor Cell Search Algorithm

NASA Technical Reports Server (NTRS)

Holst, Terry L.; Nixon, David (Technical Monitor)

1998-01-01

The objectives of this study were to develop chimera-based full potential methodology which is compatible with overflow (Euler/Navier-Stokes) chimera flow solver and to develop a fast donor cell search algorithm that is compatible with the chimera full potential approach. Results of this work included presenting a new donor cell search algorithm suitable for use with a chimera-based full potential solver. This algorithm was found to be extremely fast and simple producing donor cells as fast as 60,000 per second.

A biofilm microreactor system for simultaneous electrochemical and nuclear magnetic resonance techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Renslow, Ryan S.; Babauta, Jerome T.; Majors, Paul D.

2014-03-01

In order to fully understand electrochemically active biofilms and the limitations to their scale-up in industrial biofilm reactors, a complete picture of the microenvironments inside the biofilm is needed. Nuclear magnetic resonance (NMR) techniques are ideally suited for the study of biofilms and for probing their microenvironments because these techniques allow for non-invasive interrogation and in situ monitoring with high resolution. By combining NMR with simultaneous electrochemical techniques, it is possible to sustain and study live electrochemically active biofilms. Here, we introduce a novel biofilm microreactor system that allows for simultaneous electrochemical and NMR techniques (EC-NMR) at the microscale. Microreactorsmore » were designed with custom radiofrequency resonator coils, which allowed for NMR measurements of biofilms growing on polarized gold electrodes. For an example application of this system, we grew Geobacter sulfurreducens biofilms. NMR was used to investigate growth media flow velocities, which were compared to simulated laminar flow, and electron donor concentrations inside the biofilms. We use Monte Carlo error analysis to estimate standard deviations of the electron donor concentration measurements within the biofilm. The EC-NMR biofilm microreactor system can ultimately be used to correlate extracellular electron transfer rates with metabolic reactions and explore extracellular electron transfer mechanisms.« less

Carbon assimilation and transfer through kelp forests in the NE Atlantic is diminished under a warmer ocean climate.

PubMed

Pessarrodona, Albert; Moore, Pippa J; Sayer, Martin D J; Smale, Dan A

2018-06-03

Global climate change is affecting carbon cycling by driving changes in primary productivity and rates of carbon fixation, release and storage within Earth's vegetated systems. There is, however, limited understanding of how carbon flow between donor and recipient habitats will respond to climatic changes. Macroalgal-dominated habitats, such as kelp forests, are gaining recognition as important carbon donors within coastal carbon cycles, yet rates of carbon assimilation and transfer through these habitats are poorly resolved. Here, we investigated the likely impacts of ocean warming on coastal carbon cycling by quantifying rates of carbon assimilation and transfer in Laminaria hyperborea kelp forests-one of the most extensive coastal vegetated habitat types in the NE Atlantic-along a latitudinal temperature gradient. Kelp forests within warm climatic regimes assimilated, on average, more than three times less carbon and donated less than half the amount of particulate carbon compared to those from cold regimes. These patterns were not related to variability in other environmental parameters. Across their wider geographical distribution, plants exhibited reduced sizes toward their warm-water equatorward range edge, further suggesting that carbon flow is reduced under warmer climates. Overall, we estimated that Laminaria hyperborea forests stored ~11.49 Tg C in living biomass and released particulate carbon at a rate of ~5.71 Tg C year -1 . This estimated flow of carbon was markedly higher than reported values for most other marine and terrestrial vegetated habitat types in Europe. Together, our observations suggest that continued warming will diminish the amount of carbon that is assimilated and transported through temperate kelp forests in NE Atlantic, with potential consequences for the coastal carbon cycle. Our findings underline the need to consider climate-driven changes in the capacity of ecosystems to fix and donate carbon when assessing the impacts of climate change on carbon cycling. © 2018 The Authors Global Change Biology Published by John Wiley & Sons Ltd.

Impairment of Host Liver Repopulation by Transplanted Hepatocytes in Aged Rats and the Release by Short-Term Growth Hormone Treatment.

PubMed

Stock, Peggy; Bielohuby, Maximilian; Staege, Martin S; Hsu, Mei-Ju; Bidlingmaier, Martin; Christ, Bruno

2017-03-01

Hepatocyte transplantation is an alternative to whole liver transplantation. Yet, efficient liver repopulation by transplanted hepatocytes is low in livers of old animals. This restraint might be because of the poor proliferative capacity of aged donor hepatocytes or the regenerative impairment of the recipient livers. The age-dependent liver repopulation by transplanted wild-type hepatocytes was investigated in juvenile and senescent rats deficient in dipeptidyl-peptidase IV. Repopulation was quantified by flow cytometry and histochemical estimation of dipeptidyl-peptidase IV enzyme activity of donor cells in the negative host liver. As a potential pathway involved, expression of cell cycle proteins was assessed. Irrespective of the age of the donor hepatocytes, large cell clusters appeared in juvenile, but only small clusters in senescent host livers. Because juvenile and senescent donor hepatocytes were likewise functional, host-derived factor(s) impaired senescent host liver repopulation. Growth hormone levels were significantly higher in juvenile than in senescent rats, suggesting that growth hormone might promote host liver repopulation. Indeed, short-term treatment with growth hormone augmented senescent host liver repopulation involving the growth hormone-mediated release of the transcriptional blockade of genes associated with cell cycle progression. Short-term growth hormone substitution might improve liver repopulation by transplanted hepatocytes, thus augmenting the therapeutic benefit of clinical hepatocyte transplantation in older patients. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Determining the effect of vein visualization technology on donation success, vasovagal symptoms, anxiety and intention to re-donate in whole blood donors aged 18-30 years: A randomized controlled trial.

PubMed

Waller, D; Mondy, P; Brama, T; Fisher, J; King, A; Malkov, K; Wall-Smith, D; Ryan, L; Irving, D O

2016-08-01

Vein visualization technology (VVT) devices use near-infrared light to assist location of peripheral veins. The current study investigated the impact of VVT on donor experience and collection success for young blood donors at the Australian Red Cross Blood Service. The study in donors aged 18 to 30 years used a two intervention to one control randomized trial design with 285 new and 587 returning donors recruited at two sites. Donors reported presyncopal symptoms, phlebotomy pain, anxiety and intentions to redonate along with other measures. Participating phlebotomists rated usefulness of the technology. Flow rates, collection volumes and other donation information were taken from routine data. No significant differences were found between control and intervention groups on presyncopal symptoms, phlebotomy pain, anxiety, intentions to redonate, flow rates, collection volumes or vasovagal reactions (all P's > 0·05). Phlebotomist ratings of VVT were significantly more positive when they had less than 5 years of experience (P < 0·01) or when the vein was not visible to the naked eye (P < 0·01). Results suggest that VVT does not improve the donation experience for younger blood donors. Staff reports indicate that VVT may have some utility for assisting with difficult phlebotomies. © 2016 International Society of Blood Transfusion.

Complex Networks, Fractals and Topology Trends for Oxidative Activity of DNA in Cells for Populations of Fluorescing Neutrophils in Medical Diagnostics

NASA Astrophysics Data System (ADS)

Galich, N. E.

A novel nonlinear statistical method of immunofluorescence data analysis is presented. The data of DNA fluorescence due to oxidative activity in neutrophils nuclei of peripheral blood is analyzed. Histograms of photon counts statistics are generated using flow cytometry method. The histograms represent the distributions of fluorescence flash frequency as functions of intensity for large populations∼104-105 of fluorescing cells. We have shown that these experiments present 3D-correlations of oxidative activity of DNA for full chromosomes set in cells with spatial resolution of measurements is about few nanometers in the flow direction the jet of blood. Detailed analysis showed that large-scale correlations in oxidative activity of DNA in cells are described as networks of small- worlds (complex systems with logarithmic scaling) with self own small-world networks for given donor at given time for all states of health. We observed changes in fractal networks of oxidative activity of DNA in neutrophils in vivo and during medical treatments for classification and diagnostics of pathologies for wide spectra of diseases. Our approach based on analysis of changes topology of networks (fractal dimension) at variation the scales of networks. We produce the general estimation of health status of a given donor in a form of yes/no of answers (healthy/sick) in the dependence on the sign of plus/minus in the trends change of fractal dimensions due to decreasing the scale of nets. We had noted the increasing biodiversity of neutrophils and stochastic (Brownian) character of intercellular correlations of different neutrophils in the blood of healthy donor. In the blood of sick people we observed the deterministic cell-cell correlations of neutrophils and decreasing their biodiversity.

Paternity analysis of pollen-mediated gene flow for Fraxinus excelsior L. in a chronically fragmented landscape.

PubMed

Bacles, C F E; Ennos, R A

2008-10-01

Paternity analysis based on microsatellite marker genotyping was used to infer contemporary genetic connectivity by pollen of three population remnants of the wind-pollinated, wind-dispersed tree Fraxinus excelsior, in a deforested Scottish landscape. By deterministically accounting for genotyping error and comparing a range of assignment methods, individual-based paternity assignments were used to derive population-level estimates of gene flow. Pollen immigration into a 300 ha landscape represents between 43 and 68% of effective pollination, mostly depending on assignment method. Individual male reproductive success is unequal, with 31 of 48 trees fertilizing one seed or more, but only three trees fertilizing more than ten seeds. Spatial analysis suggests a fat-tailed pollen dispersal curve with 85% of detected pollination occurring within 100 m, and 15% spreading between 300 and 1900 m from the source. Identification of immigrating pollen sourced from two neighbouring remnants indicates further effective dispersal at 2900 m. Pollen exchange among remnants is driven by population size rather than geographic distance, with larger remnants acting predominantly as pollen donors, and smaller remnants as pollen recipients. Enhanced wind dispersal of pollen in a barren landscape ensures that the seed produced within the catchment includes genetic material from a wide geographic area. However, gene flow estimates based on analysis of non-dispersed seeds were shown to underestimate realized gene immigration into the remnants by a factor of two suggesting that predictive landscape conservation requires integrated estimates of post-recruitment gene flow occurring via both pollen and seed.

The feasibility of detecting cerebral blood flow direction using the indocyanine green video angiography.

PubMed

Murai, Yasuo; Nakagawa, Syunsuke; Matano, Fumihiro; Shirokane, Kazutaka; Teramoto, Akira; Morita, Akio

2016-10-01

The intraoperative confirmation of blood flow direction is necessary in cerebral vascular surgery. Using indocyanine green video angiography (ICG-VAG) with the FLOW 800 system, we examined the transit time of the blood vessel of interest and semiquantitatively evaluated the delay time (T1/2max) from indocyanine green (ICG) injection into the donor artery in reconstructive surgery and the middle cerebral artery (MCA) in aneurysmal surgery. The direction of cerebral blood flow (CBF), which can often be confirmed by ICG-VAG, may be more difficult to determine with faster blood flow. Here, we report our findings regarding the feasibility of detecting CBF direction using the FLOW 800 system. Twenty patients undergoing superficial temporal artery (STA) to MCA anastomosis for carotid occlusive disease and 13 patients with a small MCA aneurysm clipping were evaluated using the T1/2max, semiquantitative method with the FLOW 800 system. In STA-MCA anastomosis cases, the regions of interest (ROIs) included: the proximal donor STA and a region more than 10 mm on the distal side of the donor STA near the anastomosis site. In MCA aneurysms, the ROIs included the proximal M1 and distal M2 sides of the MCA aneurysm. T1/2max was significantly shorter for the proximal sites compared to the distal sites for all subjects (ps < 0.01). T1/2max was shorter for all subjects in the proximal sites. The direction of CBF can be determined using the FLOW 800 system.

An Exception to the Rule or a Rule for the Exception? The Potential of Using HIV-Positive Donors in Canada.

PubMed

Wright, Alissa J; Rose, Caren; Toews, Maeghan; Paquet, Michel; Corsilli, Daniel; Le Cailhier, Jean-François; Gill, John S

2017-04-01

Selected human immunodeficiency virus (HIV)-infected patients with end organ failure can safely receive an organ transplant from an HIV uninfected donor. Recent demonstration of the short term safety of organ transplantation between HIV-infected persons prompted a change in US American law to allow such transplantations. Prompted by the recent completion of the first organ transplantation between HIV-infected persons in Canada, we review Canadian law regarding the use of organs from HIV-infected donors, estimate the number of potential HIV-infected donors in Canada, and critically review considerations related to advancing organ transplantation from HIV-infected donors in Canada. Existing legislation allows organ transplantation from an HIV-infected donor under exceptional medical circumstances and therefore no change in legislation is required to increase utilization of organs from HIV-infected donors for transplantation in Canada. Among 335,793 hospital deaths between 2005 and 2009 in Canadian provinces excluding Quebec, 39 potential HIV-infected donors were identified. The actual number of HIV potential donors is estimated to be approximately 60% lower (3-5 potential donor per year), if the absence of viremia is required for transplantation. Although offering all Canadians the opportunity to donate organs is a laudable goal, further research to understand the need for HIV-positive donors and the willingness of HIV-positive recipients to accept organs from HIV-positive donors is needed to inform future policy regarding organ donation from HIV-infected persons in Canada.

Ethyl acetate as an acyl donor in the continuous flow kinetic resolution of (±)-1-phenylethylamine catalyzed by lipases.

PubMed

de Miranda, Amanda S; Miranda, Leandro S M; de Souza, Rodrigo O M A

2013-05-28

The synthesis of chiral amines is still a challenge for organic synthesis since optically pure amines are of great importance for the pharmaceutical and agrochemical industries. Among all the methodologies developed until now, chemoenzymatic dynamic kinetic resolution has proven to be useful for the preparation of enantioenriched primary chiral amines. In our continuous efforts toward the development of a continuous flow process, herein we report our results on the continuous flow kinetic resolution of (±)-1-phenylethylamine leading to the desired products with high enantiomeric ratios (>200) and short residence times (40 minutes) using ethyl acetate as the acyl donor.

U(VI) bioreduction with emulsified vegetable oil as the electron donor--model application to a field test.

PubMed

Tang, Guoping; Watson, David B; Wu, Wei-Min; Schadt, Christopher W; Parker, Jack C; Brooks, Scott C

2013-04-02

We amended a shallow fast-flowing uranium (U) contaminated aquifer with emulsified vegetable oil (EVO) and subsequently monitored the biogeochemical responses for over a year. Using a biogeochemical model developed in a companion article (Tang et al., Environ. Sci. Technol.2013, doi: 10.1021/es304641b) based on microcosm tests, we simulated geochemical and microbial dynamics in the field test during and after the 2-h EVO injection. When the lab-determined parameters were applied in the field-scale simulation, the estimated rate coefficient for EVO hydrolysis in the field was about 1 order of magnitude greater than that in the microcosms. Model results suggested that precipitation of long-chain fatty acids, produced from EVO hydrolysis, with Ca in the aquifer created a secondary long-term electron donor source. The model predicted substantial accumulation of denitrifying and sulfate-reducing bacteria, and U(IV) precipitates. The accumulation was greatest near the injection wells and along the lateral boundaries of the treatment zone where electron donors mixed with electron acceptors in the groundwater. While electron acceptors such as sulfate were generally considered to compete with U(VI) for electrons, this work highlighted their role in providing electron acceptors for microorganisms to degrade complex substrates thereby enhancing U(VI) reduction and immobilization.

Donor cycle and donor segmentation: new tools for improving blood donor management.

PubMed

Veldhuizen, I; Folléa, G; de Kort, W

2013-07-01

An adequate donor population is of key importance for the entire blood transfusion chain. For good donor management, a detailed overview of the donor database is therefore imperative. This study offers a new description of the donor cycle related to the donor management process. It also presents the outcomes of a European Project, Donor Management IN Europe (DOMAINE), regarding the segmentation of the donor population into donor types. Blood establishments (BEs) from 18 European countries, the Thalassaemia International Federation and a representative from the South-Eastern Europe Health Network joined forces in DOMAINE. A questionnaire assessed blood donor management practices and the composition of the donor population using the newly proposed DOMAINE donor segmentation. 48 BEs in 34 European countries were invited to participate. The response rate was high (88%). However, only 14 BEs could deliver data on the composition of their donor population. The data showed large variations and major imbalances in the donor population. In 79% of the countries, inactive donors formed the dominant donor type. Only in 21%, regular donors were the largest subgroup, and in 29%, the proportion of first-time donors was higher than the proportion of regular donors. Good donor management depends on a thorough insight into the flow of donors through their donor career. Segmentation of the donor database is an essential tool to understand the influx and efflux of donors. The DOMAINE donor segmentation helps BEs in understanding their donor database and to adapt their donor recruitment and retention practices accordingly. Ways to use this new tool are proposed. © 2013 International Society of Blood Transfusion.

Estimating the distance separating fluorescent protein FRET pairs

PubMed Central

van der Meer, B. Wieb; Blank, Paul S.

2014-01-01

Förster resonance energy transfer (FRET) describes a physical phenomenon widely applied in biomedical research to estimate separations between biological molecules. Routinely, genetic engineering is used to incorporate spectral variants of the green fluorescent protein (GFPs), into cellular expressed proteins. The transfer efficiency or rate of energy transfer between donor and acceptor FPs is then assayed. As appreciable FRET occurs only when donors and acceptors are in close proximity (1–10 nm), the presence of FRET may indicate that the engineered proteins associate as interacting species. For a homogeneous population of FRET pairs the separations between FRET donors and acceptors can be estimated from a measured FRET efficiency if it is assumed that donors and acceptors are randomly oriented and rotate extensively during their excited state (dynamic regime). Unlike typical organic fluorophores, the rotational correlation-times of FPs are typically much longer than their fluorescence lifetime; accordingly FPs are virtually static during their excited state. Thus, estimating separations between FP FRET pairs is problematic. To overcome this obstacle, we present here a simple method for estimating separations between FPs using the experimentally measured average FRET efficiency. This approach assumes that donor and acceptor fluorophores are randomly oriented, but do not rotate during their excited state (static regime). This approach utilizes a Monte-Carlo simulation generated look-up table that allows one to estimate the separation, normalized to the Förster distance, from the average FRET efficiency. Assuming a dynamic regime overestimates the separation significantly (by 10% near 0.5 and 30% near 0.75 efficiencies) compared to assuming a static regime, which is more appropriate for estimates of separations between FPs. PMID:23811334

CHROTRAN 1.0: A mathematical and computational model for in situ heavy metal remediation in heterogeneous aquifers

NASA Astrophysics Data System (ADS)

Hansen, Scott K.; Pandey, Sachin; Karra, Satish; Vesselinov, Velimir V.

2017-12-01

Groundwater contamination by heavy metals is a critical environmental problem for which in situ remediation is frequently the only viable treatment option. For such interventions, a multi-dimensional reactive transport model of relevant biogeochemical processes is invaluable. To this end, we developed a model, chrotran, for in situ treatment, which includes full dynamics for five species: a heavy metal to be remediated, an electron donor, biomass, a nontoxic conservative bio-inhibitor, and a biocide. Direct abiotic reduction by donor-metal interaction as well as donor-driven biomass growth and bio-reduction are modeled, along with crucial processes such as donor sorption, bio-fouling, and biomass death. Our software implementation handles heterogeneous flow fields, as well as arbitrarily many chemical species and amendment injection points, and features full coupling between flow and reactive transport. We describe installation and usage and present two example simulations demonstrating its unique capabilities. One simulation suggests an unorthodox approach to remediation of Cr(VI) contamination.

CHROTRAN: a mathematical and computational model for in situ heavy metal remediation in heterogeneous aquifers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, Scott; Pandey, Sachin; Karra, Satish

Groundwater contamination by heavy metals is a critical environmental problem for which in situ remediation is frequently the only viable treatment option. For such interventions, a three-dimensional reactive transport model of relevant biogeochemical processes is invaluable. To this end, we developed a model, CHROTRAN, for in situ treatment, which includes full dynamics for five species: a heavy metal to be remediated, an electron donor, biomass, a nontoxic conservative bio-inhibitor, and a biocide. Direct abiotic reduction by donor-metal interaction as well as donor-driven biomass growth and bio-reduction are modeled, along with crucial processes such as donor sorption, bio-fouling and biomass death.more » Our software implementation handles heterogeneous flow fields, arbitrarily many chemical species and amendment injection points, and features full coupling between flow and reactive transport. We describe installation and usage and present two example simulations demonstrating its unique capabilities. One simulation suggests an unorthodox approach to remediation of Cr(VI) contamination.« less

CHROTRAN: a mathematical and computational model for in situ heavy metal remediation in heterogeneous aquifers

DOE PAGES

Hansen, Scott; Pandey, Sachin; Karra, Satish; ...

2017-04-25

Groundwater contamination by heavy metals is a critical environmental problem for which in situ remediation is frequently the only viable treatment option. For such interventions, a three-dimensional reactive transport model of relevant biogeochemical processes is invaluable. To this end, we developed a model, CHROTRAN, for in situ treatment, which includes full dynamics for five species: a heavy metal to be remediated, an electron donor, biomass, a nontoxic conservative bio-inhibitor, and a biocide. Direct abiotic reduction by donor-metal interaction as well as donor-driven biomass growth and bio-reduction are modeled, along with crucial processes such as donor sorption, bio-fouling and biomass death.more » Our software implementation handles heterogeneous flow fields, arbitrarily many chemical species and amendment injection points, and features full coupling between flow and reactive transport. We describe installation and usage and present two example simulations demonstrating its unique capabilities. One simulation suggests an unorthodox approach to remediation of Cr(VI) contamination.« less

Mechanistic studies of the transdermal iontophoretic delivery of 5-OH-DPAT in vitro.

PubMed

Ackaert, Oliver W; Van Smeden, Jeroen; De Graan, Jeroen; Dijkstra, Durk; Danhof, Meindert; Bouwstra, Joke A

2010-01-01

A characterization and optimization of the in vitro transdermal iontophoretic transport of 5-hydroxy-2-(N,N,-di-n-propylamino)tetralin (5-OH-DPAT) is presented. The utility of acetaminophen as a marker of electroosmotic flow was studied as well. The following parameters of iontophoretic transport of 5-OH-DPAT were examined: drug donor concentration, electroosmotic contribution, influence of co-ions, current density, and composition of the acceptor phase. The steady-state flux (Flux(ss)) of acetaminophen was linearly correlated with the donor concentration and co-iontophoresis of acetaminophen did not influence the iontophoretic flux of 5-OH-DPAT, indicating that acetaminophen is an excellent marker of electroosmotic flow. Lowering the Na(+) concentration from 78 to 10 mM in the donor phase, resulted in a 2.5-fold enhancement of the Flux(ss). The Flux(ss) showed a nonlinear relation with the drug donor concentration and an excellent linear correlation with the current density. Reducing the pH of the acceptor phase from 7.4 to 6.2 resulted in a dramatic decrease of the Flux(ss) of 5-OH-DPAT, explained by a reduced electroosmotic flow and an increased counter-ion flow. Optimization of the conditions resulted in a maximum Flux(ss) of 5-OH-DPAT of 1.0 micromol x cm(-2) h(-1) demonstrating the potential of the iontophoretic delivery of this dopamine agonist for the symptomatic treatment of Parkinson's disease.

Associations of health status with subsequent blood donor behavior-An alternative perspective on the Healthy Donor Effect from Donor InSight.

PubMed

van den Hurk, Katja; Zalpuri, Saurabh; Prinsze, Femmeke J; Merz, Eva-Maria; de Kort, Wim L A M

2017-01-01

In donor health research, the 'Healthy Donor Effect' (HDE) often biases study results and hampers their interpretation. This refers to the fact that donors are a selected 'healthier' subset of a population due to both donor selection procedures and self-selection. Donors with long versus short donor careers, or with high versus low donation intensities are often compared to avoid this HDE, but underlying health differences might also cause these differences in behaviour. Our aim was to estimate to what extent a donor´s perceived health status associates with donation cessation and intensity. All active whole blood donors participating in Donor InSight (2007-2009; 11,107 male; 12,616 female) were included in this prospective cohort study. We performed Cox survival and Poisson regression analyses to assess whether self-reported health status, medication use, disease diagnosed by a physician and recently having consulted a general practitioner (GP) or specialist were associated with (time to) donation cessation and donation intensity. At the end of 2013, 44% of the donors in this study had stopped donating. Donors in self-rated good health had a 15% lower risk to stop donating compared to donors in perceived poorer health. Medication use, disease diagnoses and consulting a GP were associated with a 20-40% increased risk to stop donating and a lower donation intensity, when adjusting for age, number of donations and new donor status. Both men and women reporting good health made on average 10% more donations. Donors with a "good" health status were less likely to stop donating blood and tended to donate blood more often than donors with perceived poorer health status. This implies that the HDE is an important source of selection bias in studies on donor health and this includes studies where comparisons within donors are made. This HDE should be adjusted for appropriately when assessing health effects of donation and donors' health status may provide estimates of future donation behavior.

Prevalence, Incidence, and Residual Risks for Transfusion Transmitted HIV-1/2 Infection among Chinese Blood Donors

PubMed Central

Wang, Jingxing; Liu, Jing; Yao, Fuzhu; Wen, Guoxin; Li, Julin; Huang, Yi; Lv, Yunlai; Wen, Xiuqiong; Wright, David; Yu, Qilu; Guo, Nan; Ness, Paul; Shan, Hua

2012-01-01

Background There is little data on HIV prevalence, incidence or residual risks for transfusion transmitted HIV infection among Chinese blood donors. Methods Donations from five Chinese blood centers in 2008–2010 were screened using two rounds of ELISA testing for anti-HIV-1/2. A reactive result in either or both rounds led to Western Blot confirmatory testing. HIV prevalence and demographic correlates among first time donors, incidence rate and demographic correlates among repeat donors were examined. Weighted multivariable logistic regression analysis examined correlates of HIV confirmatory status among first time donors. Residual risks for transfusion transmitted HIV infection were evaluated based on incidence among repeat donors. Results Among 821,320 donations, 40% came from repeat donors.1,837 (0.34%) first time and 577 (0.17%) repeat donations screened reactive for anti-HIV-1/2, among which 1,310 and 419 were tested by Western Blot. 233 (17.7%) first time and 44 (10.5%) repeat donations were confirmed positive. Estimated prevalence was 66 infections per 100,000 (95% CI: 59–74) first time donors. Estimated incidence was 9/100,000 (95% CI: 7–12) person-years among repeat donors. Weighted multivariable logistic regression analysis indicate that first time donors 26–45 years old were 1.6–1.8 times likely to be HIV positive than those 25 years and younger. Donors with some college or above education were less likely to be HIV positive than those with middle school education, ORs ranging from 0.35 to 0.60. Minority were 1.6 times likely to be HIV positive than Han majority donors (OR: 1.6; CI: 1.2–2.1). No difference in prevalence was found between gender. Current HIV TTI residual risk was 5.4 (1.2–12.5) infections per million whole blood donations. Conclusion Despite the declining HIV epidemic China, estimated residual risks for transfusion transmitted HIV infection are still high, highlighting the potential blood safety yield of NAT implementation in donation screening. PMID:23113801

The effect of whole-blood donor adverse events on blood donor return rates.

PubMed

Newman, Bruce H; Newman, Daniel T; Ahmad, Raffat; Roth, Arthur J

2006-08-01

Some blood donation-related adverse events (AEs) can negatively impact the blood donor return rate (BDRR) and decrease donor retention. One-thousand randomly selected whole-blood donors were interviewed 3 weeks after a 525-mL index whole-blood donation for seven AEs. The number of return visits and duration of follow-up were recorded for each of the 1000 donors. A negative binomial regression analysis was used to determine the contribution of the four most common AEs to the BDRR, and interactions between these AEs were also evaluated. The four most common AEs were bruise alone (15.1%), sore arm "alone" (7.0%), fatigue "alone" (5.1%), and donor reaction "alone" (4.2%), where "alone" is defined to also include donors who had a bruise but no other AE. The estimated BDRR for donations without AEs was 1.32 visits per year. The estimated BDRRs for the four most common AEs were: bruise alone, 1.32 visits per year; sore arm alone, 1.30 visits per year (2% reduction in BDRR); fatigue alone, 1.06 visits per year (20% reduction in BDRR); and donor reaction alone, 0.87 visits per year (34% reduction in BDRR). The BDRR for donor reaction, fatigue, and sore arm together was 0.20 visits per year (85% reduction in BDRR). Donor reaction had the most negative impact on the BDRR. There appears to be a synergistic effect between donor reaction, fatigue, and sore arm. Theoretically, amelioration of some AEs has the potential to improve BDRRs.

Socioeconomic status and ethnicity of deceased donor kidney recipients compared to their donors.

PubMed

Adler, J T; Hyder, J A; Elias, N; Nguyen, L L; Markmann, J F; Delmonico, F L; Yeh, H

2015-04-01

Public perception and misperceptions of socioeconomic disparities affect the willingness to donate organs. To improve our understanding of the flow of deceased donor kidneys, we analyzed socioeconomic status (SES) and racial/ethnic gradients between donors and recipients. In a retrospective cohort study, traditional demographic and socioeconomic factors, as well as an SES index, were compared in 56,697 deceased kidney donor and recipient pairs transplanted between 2007 and 2012. Kidneys were more likely to be transplanted in recipients of the same racial/ethnic group as the donor (p < 0.001). Kidneys tended to go to recipients of lower SES index (50.5% of the time, p < 0.001), a relationship that remained after adjusting for other available markers of donor organ quality and SES (p < 0.001). Deceased donor kidneys do not appear to be transplanted from donors of lower SES to recipients of higher SES; this information may be useful in counseling potential donors and their families regarding the distribution of their organ gifts. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

Duration of Dengue Viremia in Blood Donors and Relationships Between Donor Viremia, Infection Incidence and Clinical Case Reports During a Large Epidemic

PubMed Central

Busch, Michael P.; Sabino, Ester C.; Brambilla, Donald; Lopes, Maria Esther; Capuani, Ligia; Chowdhury, Dhuly; McClure, Christopher; Linnen, Jeffrey M.; Prince, Harry; Simmons, Graham; Lee, Tzong-Hae; Kleinman, Steven; Custer, Brian

2016-01-01

Background. Dengue viruses (DENV-1–4) pose a transfusion-transmission risk. This study estimated the dengue RNA detection period in asymptomatic blood donors and relationships between donor viremia and dengue incidence during a large epidemic. Methods. Donor samples from the 2012 dengue transmission season in Rio de Janeiro, Brazil, were tested for DENV RNA by a transcription-mediated amplification (TMA) assay, with DENV types and viral loads determined by polymerase chain reaction. Samples collected during the first and last weeks of enrollment were tested for DENV immunoglobulin (Ig) G and IgM to estimate incidence during the study period, which was analyzed relative to nucleic acid amplification technology (NAT) yield to estimate the duration of NAT-detectable viremia and compared with reported clinical dengue cases in Rio. Results. Samples from 16 241 donations were tested; 87 (0.54%) were confirmed as DENV-4 RNA positive. Dengue IgM-positive/IgG-positive reactivity increased from 2.8% to 8.8%, indicating a 6.2% incidence (95% confidence interval [CI], 3.2%–9.1%) during the study period. Based on these data, we estimated a 9.1-day period (95% CI, 4.4–13.9 days) of RNA detectable with TMA. With 100 475 reported cases of clinical dengue, 1 RNA-positive donation was identified per 800 DENV cases. Conclusions. These parameters allow projections of dengue incidence from donor NAT yield data and vice versa, and suggest that viremic donations will be rare relative to clinical disease cases. PMID:27302934

Quantification of transplant-derived circulating cell-free DNA in absence of a donor genotype

PubMed Central

Kharbanda, Sandhya; Koh, Winston; Martin, Lance R.; Khush, Kiran K.; Valantine, Hannah; Pritchard, Jonathan K.; De Vlaminck, Iwijn

2017-01-01

Quantification of cell-free DNA (cfDNA) in circulating blood derived from a transplanted organ is a powerful approach to monitoring post-transplant injury. Genome transplant dynamics (GTD) quantifies donor-derived cfDNA (dd-cfDNA) by taking advantage of single-nucleotide polymorphisms (SNPs) distributed across the genome to discriminate donor and recipient DNA molecules. In its current implementation, GTD requires genotyping of both the transplant recipient and donor. However, in practice, donor genotype information is often unavailable. Here, we address this issue by developing an algorithm that estimates dd-cfDNA levels in the absence of a donor genotype. Our algorithm predicts heart and lung allograft rejection with an accuracy that is similar to conventional GTD. We furthermore refined the algorithm to handle closely related recipients and donors, a scenario that is common in bone marrow and kidney transplantation. We show that it is possible to estimate dd-cfDNA in bone marrow transplant patients that are unrelated or that are siblings of the donors, using a hidden Markov model (HMM) of identity-by-descent (IBD) states along the genome. Last, we demonstrate that comparing dd-cfDNA to the proportion of donor DNA in white blood cells can differentiate between relapse and the onset of graft-versus-host disease (GVHD). These methods alleviate some of the barriers to the implementation of GTD, which will further widen its clinical application. PMID:28771616

Donor impurity incorporation during layer growth of Zn II-VI semiconductors

NASA Astrophysics Data System (ADS)

Barlow, D. A.

2017-12-01

The maximum halogen donor concentration in Zn II-VI semiconductors during layer growth is studied using a standard model from statistical mechanics. Here the driving force for incorporation is an increase in entropy upon mixing of the donor impurity into the available anion lattice sites in the host binary. A formation energy opposes this increase and thus equilibrium is attained at some maximum concentration. Considering the halogen donor impurities within the Zn II-VI binary semiconductors ZnO, ZnS, ZnSe and ZnTe, a heat of reaction obtained from reported diatomic bond strengths is shown to be directly proportional to the log of maximum donor concentration. The formation energy can then be estimated and an expression for maximum donor concentration derived. Values for the maximum donor concentration with each of the halogen impurities, within the Zn II-VI compounds, are computed. This model predicts that the halogens will serve as electron donors in these compounds in order of increasing effectiveness as: F, Br, I, Cl. Finally, this result is taken to be equivalent to an alternative model where donor concentration depends upon impurity diffusion and the conduction band energy shift due to a depletion region at the growing crystal's surface. From this, we are able to estimate the diffusion activation energy for each of the impurities mentioned above. Comparisons are made with reported values and relevant conclusions presented.

Point of care hemoglobin testing in plateletpheresis donors: Noninvasive versus invasive methods.

PubMed

Mallhi, R S; Pawar, Amit; Kushwaha, Neerja; Kumar, Sudeep; Dimri, Ujjwal

2016-10-01

Predonation hemoglobin (Hb) for plateletpheresis donors is estimated by presently available invasive methods. Venous samples of only those donors whose Hb is more than 12.5 g/dl are screened for complete blood count and transfusion transmissible infections. There is a pressing need to substitute this invasive Hb test with noninvasive one to reduce donor discomfort and avoid further pricking the donor. We therefore went ahead with the aim of comparing a noninvasive Hb estimation method NBM 200 with the invasive method - Hemocue, taking SYSMEX KX-21 as a gold standard. 500 voluntary consenting plateletpheresis donors qualifying the laid down criteria for platelet donation were included in the study. Hb readings obtained by the NBM 200 and Hemocue were compared to those obtained from the fully automated hematology analyzer SYSMEX KX-21. Coefficients of correlation were found to be statistically significant at <0.0001 level of confidence. Results of Friedman's test on the three methods also showed significant difference in means. Bland-Altman plots and mountain plots also confirm the same. NBM 200 was found to be more sensitive, specific, and precise than Hemocue in detecting ineligible donors. NBM 200 was found to be more sensitive, specific, and precise as compared to Hemocue for predonation screening of Hb in plateletpheresis donors and the prime benefit it offers is that it is 'noninvasive' thereby assisting in stemming the platelet donor pool. The onus lies on the blood transfusion services to make use of appropriately validated gadgets that reduce the donor discomfort.

Donor Cell Composition and Reactivity Predict Risk of Acute Graft-versus-Host Disease after Allogeneic Hematopoietic Stem Cell Transplantation.

PubMed

Sairafi, Darius; Stikvoort, Arwen; Gertow, Jens; Mattsson, Jonas; Uhlin, Michael

2016-01-01

Background . Graft-versus-host disease (GVHD) is a serious complication after allogeneic hematopoietic stem cell transplantation (HSCT). We designed a functional assay for assessment of individual risk for acute GVHD. Study Design and Methods . Blood samples were collected from patients and donors before HSCT. Two groups of seven patients each were selected, one in which individuals developed acute GVHD grades II-IV and one in which none showed any clinical signs of GVHD. Peripheral blood mononuclear cells (PBMCs) isolated from donors were incubated in mixed lymphocyte cultures (MLCs) with recipient PBMCs. The cells were characterized by flow cytometry before and after MLC. Results . Samples from donors in the GVHD group contained significantly lower frequencies of naïve γδ T-cells and T-cells expressing NK-cell markers CD56 and CD94. Donor samples in this group also exhibited lower frequencies of naïve CD95 + T-cells compared to controls. After MLC, there were dissimilarities in the CD4/CD8 T-cell ratio and frequency of CD69 + T-cells between the two patient groups, with the non-GVHD group showing higher frequencies of CD8 + and CD69 + T-cells. Conclusion . We conclude that a thorough flow cytometric analysis of donor cells for phenotype and allogeneic reactivity may be of value when assessing pretransplant risk for severe acute GVHD.

Use of Mechanistic Modeling to Assess Interindividual Variability and Interspecies Differences in Active Uptake in Human and Rat Hepatocytes

PubMed Central

Ménochet, Karelle; Kenworthy, Kathryn E.; Houston, J. Brian

2012-01-01

Interindividual variability in activity of uptake transporters is evident in vivo, yet limited data exist in vitro, confounding in vitro-in vivo extrapolation. The uptake kinetics of seven organic anion-transporting polypeptide substrates was investigated over a concentration range in plated cryopreserved human hepatocytes. Active uptake clearance (CLactive, u), bidirectional passive diffusion (Pdiff), intracellular binding, and metabolism were estimated for bosentan, pitavastatin, pravastatin, repaglinide, rosuvastatin, telmisartan, and valsartan in HU4122 donor using a mechanistic two-compartment model in Matlab. Full uptake kinetics of rosuvastatin and repaglinide were also characterized in two additional donors, whereas for the remaining drugs CLactive, u was estimated at a single concentration. The unbound affinity constant (Km, u) and Pdiff values were consistent across donors, whereas Vmax was on average up to 2.8-fold greater in donor HU4122. Consistency in Km, u values allowed extrapolation of single concentration uptake activity data and assessment of interindividual variability in CLactive across donors. The maximal contribution of active transport to total uptake differed among donors, for example, 85 to 96% and 68 to 87% for rosuvastatin and repaglinide, respectively; however, in all cases the active process was the major contributor. In vitro-in vivo extrapolation indicated a general underprediction of hepatic intrinsic clearance, an average empirical scaling factor of 17.1 was estimated on the basis of seven drugs investigated in three hepatocyte donors, and donor-specific differences in empirical factors are discussed. Uptake Km, u and CLactive, u were on average 4.3- and 7.1-fold lower in human hepatocytes compared with our previously published rat data. A strategy for the use of rat uptake data to facilitate the experimental design in human hepatocytes is discussed. PMID:22665271

Hapl-o-Mat: open-source software for HLA haplotype frequency estimation from ambiguous and heterogeneous data.

PubMed

Schäfer, Christian; Schmidt, Alexander H; Sauter, Jürgen

2017-05-30

Knowledge of HLA haplotypes is helpful in many settings as disease association studies, population genetics, or hematopoietic stem cell transplantation. Regarding the recruitment of unrelated hematopoietic stem cell donors, HLA haplotype frequencies of specific populations are used to optimize both donor searches for individual patients and strategic donor registry planning. However, the estimation of haplotype frequencies from HLA genotyping data is challenged by the large amount of genotype data, the complex HLA nomenclature, and the heterogeneous and ambiguous nature of typing records. To meet these challenges, we have developed the open-source software Hapl-o-Mat. It estimates haplotype frequencies from population data including an arbitrary number of loci using an expectation-maximization algorithm. Its key features are the processing of different HLA typing resolutions within a given population sample and the handling of ambiguities recorded via multiple allele codes or genotype list strings. Implemented in C++, Hapl-o-Mat facilitates efficient haplotype frequency estimation from large amounts of genotype data. We demonstrate its accuracy and performance on the basis of artificial and real genotype data. Hapl-o-Mat is a versatile and efficient software for HLA haplotype frequency estimation. Its capability of processing various forms of HLA genotype data allows for a straightforward haplotype frequency estimation from typing records usually found in stem cell donor registries.

The persistence of hepatitis C virus transmission risk in China despite serologic screening of blood donations.

PubMed

Wang, Jingxing; Liu, Jing; Huang, Yi; Wright, David J; Li, Julin; Zhou, Zhongmin; He, Weilan; Yang, Tonghan; Yao, Fuzhu; Zhu, Xiangming; Wen, Guoxin; Bi, Xinhong; Tiemuer, Mei-hei-li; Wen, Xiuqiong; Huang, Mei; Cao, Ru'an; Yun, Zhongqiao; Lü, Yunlai; Ma, Hongli; Guo, Nan; Yu, Qilu; Ness, Paul; Shan, Hua

2013-10-01

A total of 2%-2.9% of the population in China is infected with hepatitis C virus (HCV). This study estimated the prevalence and incidence of HCV among Chinese blood donors. We examined whole blood and apheresis platelet donations at five Chinese blood centers in 2008 to 2010. All donations were screened using two rounds of testing for alanine aminotransferase, antibody to human immunodeficiency virus Types 1 and 2, hepatitis B surface antigen, anti-HCV, and syphilis. Screening reactivity is defined by a reactive result in one or both rounds of screening tests. Confirmatory tests (Ortho third-generation HCV enzyme immunoassay, Johnson & Johnson) were performed on anti-HCV screening-reactive samples. Confirmatory positive rates among first-time donors (prevalence) and repeat donors (incidence) were calculated by blood center and demographic categories. Donor characteristics associated with HCV confirmatory status among first-time donors were examined using trend test and multivariable logistic regression analysis. Among 821,314 donations, 40% came from repeat donors. The overall anti-HCV screening-reactive rate was 0.48%. Estimated HCV prevalence was 235 per 100,000 first-time donors; incidence was 10 per 100,000 person-years in repeat donors. In multivariable logistic regression analysis, first-time donors older than 25 years displayed higher HCV prevalence than the younger donors. Less education is associated with higher HCV prevalence. Donors 26 to 35 years old and those above 45 years displayed the highest incidence rate. High prevalence and incidence in donors indicate high residual risks for transfusion-transmitted HCV in Chinese patients. Implementation of minipool nucleic acid testing in routine donation screening may prevent a substantial number of transfusion-transmitted HCV infections. © 2013 American Association of Blood Banks.

Automated flow cytometric analysis across large numbers of samples and cell types.

PubMed

Chen, Xiaoyi; Hasan, Milena; Libri, Valentina; Urrutia, Alejandra; Beitz, Benoît; Rouilly, Vincent; Duffy, Darragh; Patin, Étienne; Chalmond, Bernard; Rogge, Lars; Quintana-Murci, Lluis; Albert, Matthew L; Schwikowski, Benno

2015-04-01

Multi-parametric flow cytometry is a key technology for characterization of immune cell phenotypes. However, robust high-dimensional post-analytic strategies for automated data analysis in large numbers of donors are still lacking. Here, we report a computational pipeline, called FlowGM, which minimizes operator input, is insensitive to compensation settings, and can be adapted to different analytic panels. A Gaussian Mixture Model (GMM)-based approach was utilized for initial clustering, with the number of clusters determined using Bayesian Information Criterion. Meta-clustering in a reference donor permitted automated identification of 24 cell types across four panels. Cluster labels were integrated into FCS files, thus permitting comparisons to manual gating. Cell numbers and coefficient of variation (CV) were similar between FlowGM and conventional gating for lymphocyte populations, but notably FlowGM provided improved discrimination of "hard-to-gate" monocyte and dendritic cell (DC) subsets. FlowGM thus provides rapid high-dimensional analysis of cell phenotypes and is amenable to cohort studies. Copyright © 2015. Published by Elsevier Inc.

Regional HLA Differences in Poland and Their Effect on Stem Cell Donor Registry Planning

PubMed Central

Schmidt, Alexander H.; Solloch, Ute V.; Pingel, Julia; Sauter, Jürgen; Böhme, Irina; Cereb, Nezih; Dubicka, Kinga; Schumacher, Stephan; Wachowiak, Jacek; Ehninger, Gerhard

2013-01-01

Regional HLA frequency differences are of potential relevance for the optimization of stem cell donor recruitment. We analyzed a very large sample (n = 123,749) of registered Polish stem cell donors. Donor figures by 1-digit postal code regions ranged from n = 5,243 (region 9) to n = 19,661 (region 8). Simulations based on region-specific haplotype frequencies showed that donor recruitment in regions 0, 2, 3 and 4 (mainly located in the south-eastern part of Poland) resulted in an above-average increase of matching probabilities for Polish patients. Regions 1, 7, 8, 9 (mainly located in the northern part of Poland) showed an opposite behavior. However, HLA frequency differences between regions were generally small. A strong indication for regionally focused donor recruitment efforts can, therefore, not be derived from our analyses. Results of haplotype frequency estimations showed sample size effects even for sizes between n≈5,000 and n≈20,000. This observation deserves further attention as most published haplotype frequency estimations are based on much smaller samples. PMID:24069237

Using rates of oxygen and nitrate reduction to map the subsurface distribution of groundwater denitrification

NASA Astrophysics Data System (ADS)

Kolbe, T.; De Dreuzy, J. R.; Abbott, B. W.; Aquilina, L.; Babey, T.; Green, C. T.; Fleckenstein, J. H.; Labasque, T.; Laverman, A.; Marçais, J.; Peiffer, S.; Thomas, Z.; Pinay, G.

2017-12-01

Widespread fertilizer application over the last 70 years has caused serious ecological and socioeconomic problems in aquatic and estuarine ecosystems. When surplus nitrogen leaches as nitrate (a major groundwater pollutant) to the aquifer, complex flow dynamics and naturally occurring degradation processes control its transport. Under the conditions of depleted oxygen and abundant electron donors, microorganisms reduce NO3- to N2 (denitrification). Denitrification rates vary over orders of magnitude among sites within the same aquifer, complicating estimation of denitrification capacity at the catchment scale. Because it is impractical or impossible to access the subsurface to directly quantify denitrification rates, reactivity is often assumed to occur continuous along flowlines, potentially resulting in substantial over- or underestimation of denitrification. Here we investigated denitrification in an unconfined crystalline aquifer in western France using a combination of common tracers (chlorofluorocarbons, O2, NO3-, and N2) measured in 16 wells to inform a time-based modeling approach. We found that spatially variable denitrification rates arise from the intersection of nitrate rich water with reactive zones defined by the abundance of electron donors (primarily pyrite). Furthermore, based on observed reaction rates of the sequential reduction of oxygen and nitrate, we present a general framework to estimate the location and intensity of the reactive zone in aquifers. Accounting for the vertical distribution of reaction rates results in large differences in estimations of net denitrification rates that assume homogeneous reactivity. This new framework provides a tractable approach for quantifying catchment and regional groundwater denitrification rates that could be used to improve estimation of groundwater resilience to nitrate pollution and develop more realistic management strategies.

Prediction of hemoglobin in blood donors using a latent class mixed-effects transition model.

PubMed

Nasserinejad, Kazem; van Rosmalen, Joost; de Kort, Wim; Rizopoulos, Dimitris; Lesaffre, Emmanuel

2016-02-20

Blood donors experience a temporary reduction in their hemoglobin (Hb) value after donation. At each visit, the Hb value is measured, and a too low Hb value leads to a deferral for donation. Because of the recovery process after each donation as well as state dependence and unobserved heterogeneity, longitudinal data of Hb values of blood donors provide unique statistical challenges. To estimate the shape and duration of the recovery process and to predict future Hb values, we employed three models for the Hb value: (i) a mixed-effects models; (ii) a latent-class mixed-effects model; and (iii) a latent-class mixed-effects transition model. In each model, a flexible function was used to model the recovery process after donation. The latent classes identify groups of donors with fast or slow recovery times and donors whose recovery time increases with the number of donations. The transition effect accounts for possible state dependence in the observed data. All models were estimated in a Bayesian way, using data of new entrant donors from the Donor InSight study. Informative priors were used for parameters of the recovery process that were not identified using the observed data, based on results from the clinical literature. The results show that the latent-class mixed-effects transition model fits the data best, which illustrates the importance of modeling state dependence, unobserved heterogeneity, and the recovery process after donation. The estimated recovery time is much longer than the current minimum interval between donations, suggesting that an increase of this interval may be warranted. Copyright © 2015 John Wiley & Sons, Ltd.

Simulation shows that HLA-matched stem cell donors can remain unidentified in donor searches

PubMed Central

Sauter, Jürgen; Solloch, Ute V.; Giani, Anette S.; Hofmann, Jan A.; Schmidt, Alexander H.

2016-01-01

The heterogeneous nature of HLA information in real-life stem cell donor registries may hamper unrelated donor searches. It is even possible that fully HLA-matched donors with incomplete HLA information are not identified. In our simulation study, we estimated the probability of these unnecessarily failed donor searches. For that purpose, we carried out donor searches in several virtual donor registries. The registries differed by size, composition with respect to HLA typing levels, and genetic diversity. When up to three virtual HLA typing requests were allowed within donor searches, the share of unnecessarily failed donor searches ranged from 1.19% to 4.13%, thus indicating that non-identification of completely HLA-matched stem cell donors is a problem of practical relevance. The following donor registry characteristics were positively correlated with the share of unnecessarily failed donor searches: large registry size, high genetic diversity, and, most strongly correlated, large fraction of registered donors with incomplete HLA typing. Increasing the number of virtual HLA typing requests within donor searches up to ten had a smaller effect. It follows that the problem of donor non-identification can be substantially reduced by complete high-resolution HLA typing of potential donors. PMID:26876789

Simulation shows that HLA-matched stem cell donors can remain unidentified in donor searches

NASA Astrophysics Data System (ADS)

Sauter, Jürgen; Solloch, Ute V.; Giani, Anette S.; Hofmann, Jan A.; Schmidt, Alexander H.

2016-02-01

The heterogeneous nature of HLA information in real-life stem cell donor registries may hamper unrelated donor searches. It is even possible that fully HLA-matched donors with incomplete HLA information are not identified. In our simulation study, we estimated the probability of these unnecessarily failed donor searches. For that purpose, we carried out donor searches in several virtual donor registries. The registries differed by size, composition with respect to HLA typing levels, and genetic diversity. When up to three virtual HLA typing requests were allowed within donor searches, the share of unnecessarily failed donor searches ranged from 1.19% to 4.13%, thus indicating that non-identification of completely HLA-matched stem cell donors is a problem of practical relevance. The following donor registry characteristics were positively correlated with the share of unnecessarily failed donor searches: large registry size, high genetic diversity, and, most strongly correlated, large fraction of registered donors with incomplete HLA typing. Increasing the number of virtual HLA typing requests within donor searches up to ten had a smaller effect. It follows that the problem of donor non-identification can be substantially reduced by complete high-resolution HLA typing of potential donors.

Safety of blood supply in the Caribbean countries: role of screening blood donors for markers of hepatitis B and C viruses.

PubMed

Cruz, Jose R; Pérez-Rosales, Maria Dolores; Zicker, Fabio; Schmunis, Gabriel A

2005-12-01

Blood transfusions carry risks of untoward reactions, including the transmission of infections, such as hepatitis B and C. Proper blood donor recruitment and selection, and adequate laboratory screening for infectious markers diminish the risk of transfusion-transmitted infections. To estimate the potential risk of acquiring transfusion-transmitted infections by hepatitis B or hepatitis C in 24 Caribbean countries during the period of 1996 to 2003. Official national reports for 1996, 2000-2003 of the yearly number of blood donors, screening coverage, and prevalence of serological markers for infectious diseases were used to estimate the risk of patients receiving an HBV- or HCV-positive unit of blood, and of developing an infection after receiving a positive unit. Estimates of number of infections transmitted through transfusion and number of infections prevented by screening of blood were also obtained. During the period analyzed, HBV screening coverage among blood donors was 100% in all countries with the exception of Grenada (0% in 1996) and Saint Lucia (99.5% in 2002). For HCV, only 10 countries reported universal screening in 1996, while 15 did in 2003. The number of countries that did not screen any units for HCV decreased from 11 in 1996 to five in 2003. In general, high prevalence rates of HBV (10-75 per 1000 donors) and HCV (7-19.3 per 1000 donors) markers were found in the majority of countries. We estimated that 235 infections by HCV (1:12471 donations) and two infections by HBV (1:1465373) were transmitted through transfusion because of lack of screening. On the other hand, screening of blood for transfusion prevented 21 005 HCV and 22 100 HBV infections. Blood donor recruitment and coverage of screening for transfusion-transmitted infections, especially HCV, must be improved in the Caribbean countries.

Effects of the liver volume and donor steatosis on errors in the estimated standard liver volume.

PubMed

Siriwardana, Rohan Chaminda; Chan, See Ching; Chok, Kenneth Siu Ho; Lo, Chung Mau; Fan, Sheung Tat

2011-12-01

An accurate assessment of donor and recipient liver volumes is essential in living donor liver transplantation. Many liver donors are affected by mild to moderate steatosis, and steatotic livers are known to have larger volumes. This study analyzes errors in liver volume estimation by commonly used formulas and the effects of donor steatosis on these errors. Three hundred twenty-five Asian donors who underwent right lobe donor hepatectomy were the subjects of this study. The percentage differences between the liver volumes from computed tomography (CT) and the liver volumes estimated with each formula (ie, the error percentages) were calculated. Five popular formulas were tested. The degrees of steatosis were categorized as follows: no steatosis [n = 178 (54.8%)], ≤ 10% steatosis [n = 128 (39.4%)], and >10% to 20% steatosis [n = 19 (5.8%)]. The median errors ranged from 0.6% (7 mL) to 24.6% (360 mL). The lowest was seen with the locally derived formula. All the formulas showed a significant association between the error percentage and the CT liver volume (P < 0.001). Overestimation was seen with smaller liver volumes, whereas underestimation was seen with larger volumes. The locally derived formula was most accurate when the liver volume was 1001 to 1250 mL. A multivariate analysis showed that the estimation error was dependent on the liver volume (P = 0.001) and the anthropometric measurement that was used in the calculation (P < 0.001) rather than steatosis (P ≥ 0.07). In conclusion, all the formulas have a similar pattern of error that is possibly related to the anthropometric measurement. Clinicians should be aware of this pattern of error and the liver volume with which their formula is most accurate. Copyright © 2011 American Association for the Study of Liver Diseases.

Fragment charge difference method for estimating donor-acceptor electronic coupling: Application to DNA π-stacks

NASA Astrophysics Data System (ADS)

Voityuk, Alexander A.; Rösch, Notker

2002-09-01

The purpose of this communication is two-fold. We introduce the fragment charge difference (FCD) method to estimate the electron transfer matrix element HDA between a donor D and an acceptor A, and we apply this method to several aspects of hole transfer electronic couplings in π-stacks of DNA, including systems with several donor-acceptor sites. Within the two-state model, our scheme can be simplified to recover a convenient estimate of the electron transfer matrix element HDA=(1-Δq2)1/2(E2-E1)/2 based on the vertical excitation energy E2-E1 and the charge difference Δq between donor and acceptor. For systems with strong charge separation, Δq≳0.95, one should resort to the FCD method. As favorable feature, we demonstrate the stability of the FCD approach for systems which require an approach beyond the two-state model. On the basis of ab initio calculations of various DNA related systems, we compared three approaches for estimating the electronic coupling: the minimum splitting method, the generalized Mulliken-Hush (GMH) scheme, and the FCD approach. We studied the sensitivity of FCD and GMH couplings to the donor-acceptor energy gap and found both schemes to be quite robust; they are applicable also in cases where donor and acceptor states are off resonance. In the application to π-stacks of DNA, we demonstrated for the Watson-Crick pair dimer [(GC),(GC)] how structural changes considerably affect the coupling strength of electron hole transfer. For models of three Watson-Crick pairs, we showed that the two-state model significantly overestimates the hole transfer coupling whereas simultaneous treatment of several states leads to satisfactory results.

Kidney-Failure Risk Projection for the Living Kidney-Donor Candidate.

PubMed

Grams, Morgan E; Sang, Yingying; Levey, Andrew S; Matsushita, Kunihiro; Ballew, Shoshana; Chang, Alex R; Chow, Eric K H; Kasiske, Bertram L; Kovesdy, Csaba P; Nadkarni, Girish N; Shalev, Varda; Segev, Dorry L; Coresh, Josef; Lentine, Krista L; Garg, Amit X

2016-02-04

Evaluation of candidates to serve as living kidney donors relies on screening for individual risk factors for end-stage renal disease (ESRD). To support an empirical approach to donor selection, we developed a tool that simultaneously incorporates multiple health characteristics to estimate a person's probable long-term risk of ESRD if that person does not donate a kidney. We used risk associations from a meta-analysis of seven general population cohorts, calibrated to the population-level incidence of ESRD and mortality in the United States, to project the estimated long-term incidence of ESRD among persons who do not donate a kidney, according to 10 demographic and health characteristics. We then compared 15-year projections with the observed risk among 52,998 living kidney donors in the United States. A total of 4,933,314 participants from seven cohorts were followed for a median of 4 to 16 years. For a 40-year-old person with health characteristics that were similar to those of age-matched kidney donors, the 15-year projections of the risk of ESRD in the absence of donation varied according to race and sex; the risk was 0.24% among black men, 0.15% among black women, 0.06% among white men, and 0.04% among white women. Risk projections were higher in the presence of a lower estimated glomerular filtration rate, higher albuminuria, hypertension, current or former smoking, diabetes, and obesity. In the model-based lifetime projections, the risk of ESRD was highest among persons in the youngest age group, particularly among young blacks. The 15-year observed risks after donation among kidney donors in the United States were 3.5 to 5.3 times as high as the projected risks in the absence of donation. Multiple demographic and health characteristics may be used together to estimate the projected long-term risk of ESRD among living kidney-donor candidates and to inform acceptance criteria for kidney donors. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others.).

Carrier concentration dependence of donor activation energy in n-type GaN epilayers grown on Si (1 1 1) by plasma-assisted MBE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumar, Mahesh; Central Research Laboratory, Bharat Electronics, Bangalore 560 013; Bhat, Thirumaleshwara N.

Highlights: ► The n-type GaN layers were grown by plasma-assisted molecular beam epitaxy. ► The optical characteristics of a donor level in Si-doped GaN were studied. ► Activation energy of a Si-related donor was estimated from temperature dependent PL measurements. ► PL peak positions, FWHM of PL and activation energies are found to be proportional to the cube root of carrier density. ► The involvement of donor levels is supported by the temperature-dependent electron concentration measurements. -- Abstract: The n-type GaN layers were grown by plasma-assisted MBE and either intentionally doped with Si or unintentionally doped. The optical characteristics ofmore » a donor level in Si-doped, GaN were studied in terms of photoluminescence (PL) spectroscopy as a function of electron concentration. Temperature dependent PL measurements allowed us to estimate the activation energy of a Si-related donor from temperature-induced decay of PL intensity. PL peak positions, full width at half maximum of PL and activation energies are found to be proportional to the cube root of carrier density. The involvement of donor levels is supported by the temperature-dependent electron concentration measurements.« less

Correlation between donor age and organs transplanted per donor: our experience in Japan.

PubMed

Ashikari, J; Omiya, K; Konaka, S; Nomoto, K

2014-05-01

The shortage of available organs for transplantation is a worldwide issue. To maximize the number of transplantations, increasing the number of organs transplanted per donor (OTPD) is widely recognized as an important factor for improving the shortage. In Japan, we have had 211 donors, 1112 organs transplanted, and 924 recipients receiving the transplants, resulting in 4.4 ± 1.4 recipients receiving transplants per donor and 5.3 ± 1.6 OTPD as of February 2013. Because donor age is a well-recognized factor of donor suitability, we analyzed the correlation between donor age group and OTPD. Only the age group 60 to 69 years and the age group 70 to 79 years were significantly different (P < .05) from adjacent age groups. We estimate that a donor under age 70 years has the potential to donate 4.6 to 6.7 organs. Copyright © 2014 Elsevier Inc. All rights reserved.

Flow-enhanced solution printing of all-polymer solar cells

DOE PAGES

Diao, Ying; Zhou, Yan; Kurosawa, Tadanori; ...

2015-08-12

Morphology control of solution coated solar cell materials presents a key challenge limiting their device performance and commercial viability. Here we present a new concept for controlling phase separation during solution printing using an all-polymer bulk heterojunction solar cell as a model system. The key aspect of our method lies in the design of fluid flow using a microstructured printing blade, on the basis of the hypothesis of flow-induced polymer crystallization. Our flow design resulted in a similar to 90% increase in the donor thin film crystallinity and reduced microphase separated donor and acceptor domain sizes. The improved morphology enhancedmore » all metrics of solar cell device performance across various printing conditions, specifically leading to higher short-circuit current, fill factor, open circuit voltage and significantly reduced device-to-device variation. However, we expect our design concept to have broad applications beyond all-polymer solar cells because of its simplicity and versatility.« less

Flow-enhanced solution printing of all-polymer solar cells

PubMed Central

Diao, Ying; Zhou, Yan; Kurosawa, Tadanori; Shaw, Leo; Wang, Cheng; Park, Steve; Guo, Yikun; Reinspach, Julia A.; Gu, Kevin; Gu, Xiaodan; Tee, Benjamin C. K.; Pang, Changhyun; Yan, Hongping; Zhao, Dahui; Toney, Michael F.; Mannsfeld, Stefan C. B.; Bao, Zhenan

2015-01-01

Morphology control of solution coated solar cell materials presents a key challenge limiting their device performance and commercial viability. Here we present a new concept for controlling phase separation during solution printing using an all-polymer bulk heterojunction solar cell as a model system. The key aspect of our method lies in the design of fluid flow using a microstructured printing blade, on the basis of the hypothesis of flow-induced polymer crystallization. Our flow design resulted in a ∼90% increase in the donor thin film crystallinity and reduced microphase separated donor and acceptor domain sizes. The improved morphology enhanced all metrics of solar cell device performance across various printing conditions, specifically leading to higher short-circuit current, fill factor, open circuit voltage and significantly reduced device-to-device variation. We expect our design concept to have broad applications beyond all-polymer solar cells because of its simplicity and versatility. PMID:26264528

Geographic exposure risk of variant Creutzfeldt-Jakob disease in US blood donors: a risk-ranking model to evaluate alternative donor-deferral policies.

PubMed

Yang, Hong; Huang, Yin; Gregori, Luisa; Asher, David M; Bui, Travis; Forshee, Richard A; Anderson, Steven A

2017-04-01

Variant Creutzfeldt-Jakob disease (vCJD) has been transmitted by blood transfusion (TTvCJD). The US Food and Drug Administration (FDA) recommends deferring blood donors who resided in or traveled to 30 European countries where they may have been exposed to bovine spongiform encephalopathy (BSE) through beef consumption. Those recommendations warrant re-evaluation, because new cases of BSE and vCJD have markedly abated. The FDA developed a risk-ranking model to calculate the geographic vCJD risk using country-specific case rates and person-years of exposure of US blood donors. We used the reported country vCJD case rates, when available, or imputed vCJD case rates from reported BSE and UK beef exports during the risk period. We estimated the risk reduction and donor loss should the deferral be restricted to a few high-risk countries. We also estimated additional risk reduction by leukocyte reduction (LR) of red blood cells (RBCs). The United Kingdom, Ireland, and France had the greatest vCJD risk, contributing approximately 95% of the total risk. The model estimated that deferring US donors who spent extended periods of time in these three countries, combined with currently voluntary LR (95% of RBC units), would reduce the vCJD risk by 89.3%, a reduction similar to that achieved under the current policy (89.8%). Limiting deferrals to exposure in these three countries would potentially allow donations from an additional 100,000 donors who are currently deferred. Our analysis suggests that a deferral option focusing on the three highest risk countries would achieve a level of blood safety similar to that achieved by the current policy. © 2016 AABB.

Health care costs for the evaluation, surgery, and follow-up care of living kidney donors.

PubMed

Habbous, Steven; Sarma, Sisira; Barnieh, Lianne; McArthur, Eric; Klarenbach, Scott; Manns, Braden; Begen, Mehmet A; Lentine, Krista L; Garg, Amit X

2018-04-19

The health care costs to evaluate, perform surgery, and follow a living kidney donor for the year after donation are poorly described. We obtained information on the health care costs of 1099 living kidney donors between April 1, 2004 and March 31, 2014 from Ontario, Canada using comprehensive health care administrative databases. We estimated the cost of 3 periods of the living donation process: the predonation evaluation period (start of evaluation until the day before donation), perioperative period (day of donation until 30-days postdonation), and 1 year of follow-up period (after perioperative period until 1-year postdonation). We analyzed data for donors and healthy matched nondonor controls using regression-based methods to estimate the incremental cost of living donation. Costs are presented from the perspective of the Canadian health care payer (2017 $CAD). The incremental health care costs (compared with controls) for the evaluation, perioperative, and follow-up periods were $3,596 (95% confidence interval (CI) $3,350-$3,842), $11,694 ($11,415-$11,973), and $1,011 ($793-$1,230), respectively, totalling $16,290 ($15,814-$16,767). The evaluation cost was higher if the intended recipient started dialysis part-way through the donor evaluation [$886 ($19, $1,752)]. The perioperative cost varied across transplant centers (p<0.0001). While substantial costs of living donor care are related to the nephrectomy procedure, comprehensive assessment of costs must also include the evaluation and follow-up periods. These estimates are informative for planning future work to support and expand living donation and transplantation, and directing efforts to improve the cost efficiency of living donor care.

Gene flow in genetically modified wheat.

PubMed

Rieben, Silvan; Kalinina, Olena; Schmid, Bernhard; Zeller, Simon L

2011-01-01

Understanding gene flow in genetically modified (GM) crops is critical to answering questions regarding risk-assessment and the coexistence of GM and non-GM crops. In two field experiments, we tested whether rates of cross-pollination differed between GM and non-GM lines of the predominantly self-pollinating wheat Triticum aestivum. In the first experiment, outcrossing was studied within the field by planting "phytometers" of one line into stands of another line. In the second experiment, outcrossing was studied over distances of 0.5-2.5 m from a central patch of pollen donors to adjacent patches of pollen recipients. Cross-pollination and outcrossing was detected when offspring of a pollen recipient without a particular transgene contained this transgene in heterozygous condition. The GM lines had been produced from the varieties Bobwhite or Frisal and contained Pm3b or chitinase/glucanase transgenes, respectively, in homozygous condition. These transgenes increase plant resistance against pathogenic fungi. Although the overall outcrossing rate in the first experiment was only 3.4%, Bobwhite GM lines containing the Pm3b transgene were six times more likely than non-GM control lines to produce outcrossed offspring. There was additional variation in outcrossing rate among the four GM-lines, presumably due to the different transgene insertion events. Among the pollen donors, the Frisal GM line expressing a chitinase transgene caused more outcrossing than the GM line expressing both a chitinase and a glucanase transgene. In the second experiment, outcrossing after cross-pollination declined from 0.7-0.03% over the test distances of 0.5-2.5 m. Our results suggest that pollen-mediated gene flow between GM and non-GM wheat might only be a concern if it occurs within fields, e.g. due to seed contamination. Methodologically our study demonstrates that outcrossing rates between transgenic and other lines within crops can be assessed using a phytometer approach and that gene-flow distances can be efficiently estimated with population-level PCR analyses. © 2011 Rieben et al.

Gene Flow in Genetically Modified Wheat

PubMed Central

Rieben, Silvan; Kalinina, Olena; Schmid, Bernhard; Zeller, Simon L.

2011-01-01

Understanding gene flow in genetically modified (GM) crops is critical to answering questions regarding risk-assessment and the coexistence of GM and non-GM crops. In two field experiments, we tested whether rates of cross-pollination differed between GM and non-GM lines of the predominantly self-pollinating wheat Triticum aestivum. In the first experiment, outcrossing was studied within the field by planting “phytometers” of one line into stands of another line. In the second experiment, outcrossing was studied over distances of 0.5–2.5 m from a central patch of pollen donors to adjacent patches of pollen recipients. Cross-pollination and outcrossing was detected when offspring of a pollen recipient without a particular transgene contained this transgene in heterozygous condition. The GM lines had been produced from the varieties Bobwhite or Frisal and contained Pm3b or chitinase/glucanase transgenes, respectively, in homozygous condition. These transgenes increase plant resistance against pathogenic fungi. Although the overall outcrossing rate in the first experiment was only 3.4%, Bobwhite GM lines containing the Pm3b transgene were six times more likely than non-GM control lines to produce outcrossed offspring. There was additional variation in outcrossing rate among the four GM-lines, presumably due to the different transgene insertion events. Among the pollen donors, the Frisal GM line expressing a chitinase transgene caused more outcrossing than the GM line expressing both a chitinase and a glucanase transgene. In the second experiment, outcrossing after cross-pollination declined from 0.7–0.03% over the test distances of 0.5–2.5 m. Our results suggest that pollen-mediated gene flow between GM and non-GM wheat might only be a concern if it occurs within fields, e.g. due to seed contamination. Methodologically our study demonstrates that outcrossing rates between transgenic and other lines within crops can be assessed using a phytometer approach and that gene-flow distances can be efficiently estimated with population-level PCR analyses. PMID:22216349

Statistical analysis of donation--transfusion data with complex correlation.

PubMed

Reilly, Marie; Szulkin, Robert

2007-12-30

Blood-borne transmission of disease is estimated from linked data records from blood donors and transfusion recipients. However, such data are characterized by complex correlation due to donors typically contributing many donations and recipients being transfused with multiple units of blood product. In this paper, we present a method for analysing such data, by using a modification of a nested case-control design. For recipients who develop the disease of interest (cases) and their matched controls, all donors who contributed blood to these individuals define clusters or 'families' of related individuals. Using a Cox regression model for the hazard of the individuals within clusters of donors, we estimate the risk of transmission, and a bootstrap step provides valid standard errors provided the clusters are independent. As an illustration, we apply the method to the analysis of a large database of Swedish donor and recipient records linked to the population cancer register. We investigate whether there is an increased risk of cancer in recipients transfused with blood from donors who develop cancer after donating. Our method provides a powerful alternative to the small 'look-back' studies typical of transfusion medicine and can make an important contribution to haemovigilance efforts. Copyright (c) 2007 John Wiley & Sons, Ltd.

Donor-estimated GFR as an appropriate criterion for allocation of ECD kidneys into single or dual kidney transplantation.

PubMed

Snanoudj, R; Rabant, M; Timsit, M O; Karras, A; Savoye, E; Tricot, L; Loupy, A; Hiesse, C; Zuber, J; Kreis, H; Martinez, F; Thervet, E; Méjean, A; Lebret, T; Legendre, C; Delahousse, M

2009-11-01

It has been suggested that dual kidney transplantation (DKT) improves outcomes for expanded criteria donor (ECD) kidneys. However, no criteria for allocation to single or dual transplantation have been assessed prospectively. The strategy of DKT remains underused and potentially eligible kidneys are frequently discarded. We prospectively compared 81 DKT and 70 single kidney transplant (SKT) receiving grafts from ECD donors aged >65 years, allocated according to donor estimated glomerular filtration rate (eGFR): DKT if eGFR between 30 and 60 mL/min, SKT if eGFR greater than 60 mL/min. Patient and graft survival were similar in the two groups. In the DKT group, 13/81 patients lost one of their two kidneys due to hemorrhage, arterial or venous thrombosis. Mean eGFR at month 12 was similar in the DKT and SKT groups (47.8 mL/min and 46.4 mL/min, respectively). Simulated allocation of kidneys according to criteria based on day 0 donor parameters such as those described by Remuzzi et al., Andres et al. and UNOS, did not indicate an improvement in 12-month eGFR compared to our allocation based on donor eGFR.

Plasma Protein Corona Modulates the Vascular Wall Interaction of Drug Carriers in a Material and Donor Specific Manner

PubMed Central

Sobczynski, Daniel J.; Charoenphol, Phapanin; Heslinga, Michael J.; Onyskiw, Peter J.; Namdee, Katawut; Thompson, Alex J.; Eniola-Adefeso, Omolola

2014-01-01

The nanoscale plasma protein interaction with intravenously injected particulate carrier systems is known to modulate their organ distribution and clearance from the bloodstream. However, the role of this plasma protein interaction in prescribing the adhesion of carriers to the vascular wall remains relatively unknown. Here, we show that the adhesion of vascular-targeted poly(lactide-co-glycolic-acid) (PLGA) spheres to endothelial cells is significantly inhibited in human blood flow, with up to 90% reduction in adhesion observed relative to adhesion in simple buffer flow, depending on the particle size and the magnitude and pattern of blood flow. This reduced PLGA adhesion in blood flow is linked to the adsorption of certain high molecular weight plasma proteins on PLGA and is donor specific, where large reductions in particle adhesion in blood flow (>80% relative to buffer) is seen with ∼60% of unique donor bloods while others exhibit moderate to no reductions. The depletion of high molecular weight immunoglobulins from plasma is shown to successfully restore PLGA vascular wall adhesion. The observed plasma protein effect on PLGA is likely due to material characteristics since the effect is not replicated with polystyrene or silica spheres. These particles effectively adhere to the endothelium at a higher level in blood over buffer flow. Overall, understanding how distinct plasma proteins modulate the vascular wall interaction of vascular-targeted carriers of different material characteristics would allow for the design of highly functional delivery vehicles for the treatment of many serious human diseases. PMID:25229244

Identification of Preferential Groundwater Flow Pathways from Local Tracer Breakthrough Curves

NASA Astrophysics Data System (ADS)

Kokkinaki, A.; Sleep, B. E.; Dearden, R.; Wealthall, G.

2009-12-01

Characterizing preferential groundwater flow paths in the subsurface is a key factor in the design of in situ remediation technologies. When applying reaction-based remediation methods, such as enhanced bioremediation, preferential flow paths result in fast solute migration and potentially ineffective delivery of reactants, thereby adversely affecting treatment efficiency. The presence of such subsurface conduits was observed at the SABRe (Source Area Bioremediation) research site. Non-uniform migration of contaminants and electron donor during the field trials of enhanced bioremediation supported this observation. To better determine the spatial flow field of the heterogeneous aquifer, a conservative tracer test was conducted. Breakthrough curves were obtained at a reference plane perpendicular to the principal groundwater flow direction. The resulting dataset was analyzed using three different methods: peak arrival times, analytical solution fitting and moment analysis. Interpretation using the peak arrival time method indicated areas of fast plume migration. However, some of the high velocities are supported by single data points, thus adding considerable uncertainty to the estimated velocity distribution. Observation of complete breakthrough curves indicated different types of solute breakthrough, corresponding to different transport mechanisms. Sharp peaks corresponded to high conductivity preferential flow pathways, whereas more dispersed breakthrough curves with long tails were characteristic of significant dispersive mixing and dilution. While analytical solutions adequately quantified flow characteristics for the first type of curves, they failed to do so for the second type, in which case they gave unrealistic results. Therefore, a temporal moment analysis was performed to obtain complete spatial distributions of mass recovery, velocity and dispersivity. Though the results of moment analysis qualitatively agreed with the results of previous methods, more realistic estimates of velocities were obtained and the presence of one major preferential flow pathway was confirmed. However, low mass recovery and deviations from the 10% scaling rule for dispersivities indicate that insufficient spatial and temporal monitoring, as well as interpolation and truncation errors introduced uncertainty in the flow and transport parameters estimated by the method of moments. The results of the three analyses are valuable for enhancing the understanding of mass transport and remediation performance. Comparing the different interpretation methods, increasing the amount of concentration data considered in the analysis, the derived velocity fields were smoother and the estimated local velocities and dispersivities became more realistic. In conclusion, moment analysis is a method that represents a smoothed average of the velocity across the entire breakthrough curve, whereas the peak arrival time, which may be a less well constrained estimate, represents the physical peak arrival and typically yields a higher velocity than the moment analysis. This is an important distinction when applying the results of the tracer test to field sites.

Early Outcomes of the New UK Deceased Donor Kidney Fast-Track Offering Scheme.

PubMed

Callaghan, Chris J; Mumford, Lisa; Pankhurst, Laura; Baker, Richard J; Bradley, J Andrew; Watson, Christopher J E

2017-12-01

The UK Kidney Fast-Track Scheme (KFTS) was introduced in 2012 to identify kidneys at high risk of discard and to rapidly facilitate transplantation. A retrospective analysis of kidneys transplanted through the KFTS was undertaken. UK Transplant Registry data were collected on deceased donor kidneys implanted between November 1, 2012, and April 30, 2015, (donation after brain death [DBD] donors) and March 1, 2013, and April 30, 2015 (donation after circulatory death [DCD] donors). Posttransplant outcomes included 1-year estimated glomerular filtration rate and death-censored graft survival (DCGS). Over the study period, 523 deceased donor kidneys were transplanted through the KFTS and 4174 via the standard National Kidney Allocation Scheme (NKAS). Kidneys in the KFTS were more likely to be from older diabetic donors, had a higher frequency of poor ex vivo perfusion, had longer cold ischemic times, and were transplanted into older recipients. One-year DCGS of KFTS and NKAS DBD donor kidneys was similar (94% vs 95%; P = 0.70), but for DCD donor kidneys, DCGS was lower in those allocated via the KFTS (91% versus 95%; P = 0.04). Median 1-year estimated glomerular filtration rate for DBD donor kidneys was lower in those allocated via the KFTS (49 vs 52 mL/min per 1.73 m; P = 0.01), but for DCD kidneys, there was no difference (45 vs 48 mL/min per 1.73 m; P = 0.10). Although KFTS kidneys have less favorable donor, graft, and recipient risk factors than NKAS kidneys, short-term graft and patient outcomes are acceptable. National schemes that identify and rapidly offer kidneys at high risk of discard may contribute to minimizing the unnecessary discard of organs.

Hemodynamic resuscitation with arginine vasopressin reduces lung injury after brain death in the transplant donor.

PubMed

Rostron, Anthony J; Avlonitis, Vassilios S; Cork, David M W; Grenade, Danielle S; Kirby, John A; Dark, John H

2008-02-27

The autonomic storm accompanying brain death leads to neurogenic pulmonary edema and triggers development of systemic and pulmonary inflammatory responses. Neurogenic vasoplegia exacerbates the pulmonary injury caused by brain death and primes the lung for ischemia reperfusion injury and primary graft dysfunction in the recipient. Donor resuscitation with norepinephrine ameliorates the inflammatory response to brain death, however norepinephrine has deleterious effects, particularly on the heart. We tested the hypothesis that arginine vasopressin is a suitable alternative to norepinephrine in managing the hypotensive brain dead donor. Brain death was induced in Wistar rats by intracranial balloon inflation. Pulmonary capillary leak was estimated using radioiodinated albumin. Development of pulmonary edema was assessed by measurement of wet and dry lung weights. Cell surface expression of CD11b/CD18 by neutrophils was determined using flow cytometry. Enzyme-linked immunosorbent assays were used to measure the levels of TNFalpha, IL-1beta, CINC-1, and CINC-3 in serum and bronchoalveolar lavage. Quantitative reverse-transcription polymerase chain reaction was used to determine the expression of cytokine mRNA (IL-1beta, CINC-1 and CINC-3) in lung tissue. There was a significant increase in pulmonary capillary permeability, wet/dry lung weight ratios, neutrophil integrin expression and pro-inflammatory cytokines in serum (TNFalpha, IL-1beta, CINC-1 and CINC-3), bronchoalveolar lavage (TNFalpha and IL-1beta) and lung tissue (IL-1beta and CINC-1) in braindead animals compared to controls. Correction of neurogenic hypotension with either arginine vasopressin or norepinephrine limits edema, reduces pulmonary capillary leak, and modulates systemic and pulmonary inflammatory responses to brain death. Arginine vasopressin and norepinephrine are equally effective in treating the hypotensive pulmonary donor in this rodent model.

Financing HIV Programming: How Much Should Low- And Middle-Income Countries and their Donors Pay?

PubMed Central

Galárraga, Omar; Wirtz, Veronika J.; Santa-Ana-Tellez, Yared; Korenromp, Eline L.

2013-01-01

Global HIV control funding falls short of need. To maximize health outcomes, it is critical that national governments sustain reasonable commitments, and that international donor assistance be distributed according to country needs and funding gaps. We develop a country classification framework in terms of actual versus expected national domestic funding, considering resource needs and donor financing. With UNAIDS and World Bank data, we examine domestic and donor HIV program funding in relation to need in 84 low- and middle-income countries. We estimate expected domestic contributions per person living with HIV (PLWH) as a function of per capita income, relative size of the health sector, and per capita foreign debt service. Countries are categorized according to levels of actual versus expected domestic contributions, and resource gap. Compared to national resource needs (UNAIDS Investment Framework), we identify imbalances among countries in actual versus expected domestic and donor contributions: 17 countries, with relatively high HIV prevalence and GNI per capita, have domestic funding below expected (median per PLWH $143 and $376, respectively), yet total available funding including from donors would exceed the need ($368 and $305, respectively) if domestic contribution equaled expected. Conversely, 27 countries have actual domestic funding above the expected (medians $294 and $149) but total (domestic+donor) funding does not meet estimated need ($685 and $1,173). Across the 84 countries, in 2009, estimated resource need totaled $10.3 billion, actual domestic contributions $5.1 billion and actual donor contributions $3.7 billion. If domestic contributions would increase to the expected level in countries where the actual was below expected, total domestic contributions would increase to $7.4 billion, turning a funding gap of $1.5 billion into a surplus of $0.8 billion. Even with imperfect funding and resource-need data, the proposed country classification could help improve coherence and efficiency in domestic and international allocations. PMID:23861772

Egg banking in the United States: current status of commercially available cryopreserved oocytes.

PubMed

Quaas, Alexander M; Melamed, Alexander; Chung, Karine; Bendikson, Kristin A; Paulson, Richard J

2013-03-01

To estimate the current availability of donor cryopreserved oocytes and to describe the emerging phenomenon of commercial egg banks (CEBs) in the United States. Cross-sectional survey of CEBs. E-mail, telephone, and fax survey of all CEB scientific directors, conducted April 2012. None. None. Number and location of CEBs in the United States, years in existence, number of donors, number of available oocytes, level of donor anonymity, donor screening, cost of oocytes to recipients, freezing/thawing technique, pregnancy statistics. Seven CEBs were identified and surveyed (response rate: 100%). The CEBs used three distinct operational models, had been in existence for a median of 2 years (range: 1 to 8 years), with a median 21.5 (range: 6 to 100) donors and 120 (range: 20 to 1,000) currently available oocytes. The median recommended minimum number of eggs to obtain was six (range: four to seven), at an estimated mean cost per oocyte of $2,225 (range: $1,500 to $2,500). An estimated 3,130 oocytes from 294 donors are currently stored for future use. Of these CEBs, 6 (86%) of 7 use vitrification as cryopreservation method. To date, 8,780 frozen donor oocytes from CEBs have been used for in vitro fertilization, resulting in 602 pregnancies. Pregnancy rates per oocyte, available for 5 (71%) of 7 CEBs, were 532 (7.5%) of 7,080 for CEBs using vitrification and 70 (10%) of 700 for the single CEB using slow freezing as cryopreservation method. Frozen donor eggs are currently widely available in the United States. Three different operational models are currently used, resulting in more than 600 pregnancies from oocytes obtained at CEBs. The majority of CEBs use vitrification as cryopreservation technique. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Living Liver Donor Selection and Resection at the University of Tokyo Hospital.

PubMed

Akamatsu, N; Kokudo, N

2016-05-01

Donor selection and operative procedures for adult-to-adult living donor liver transplantation at the University of Tokyo are presented. Donor selection criteria are as follows: age between 20 and 65 years, within 3 degrees of consanguinity, without coercion, free from any major comorbidities, body mass index (BMI) < 30, and ABO blood type identical or compatible. Liver biopsy is indicated for BMI > 25 kg/m(2) or any liver function abnormality, and those with macroscopic steatosis >10% are rejected. Thereafter, an indocyanine green retention test and dynamic computed tomography are evaluated. Graft type is determined based on computed tomography volumetry. An estimated graft volume of 40% to recipient standard liver volume ratio is the lower limit. For donor safety, the left liver is the first choice, provided that it satisfies the lower limit. Otherwise, right liver harvesting is indicated, providing that the estimated remnant liver volume is >30% of the donor's total liver volume. A posterior sector graft is a possible option. Between 1996 and 2014, 462 donor hepatectomies were performed, with 257 right livers, 179 left livers, and 26 posterior sectors. There was no mortality, and the incidence of morbidity grades I, II, IIIa, and IIIb was 16%, 5%, 5%, and 3%, respectively, without a difference between right and left liver grafts. The left liver was used without impairing recipient outcome. Two aborted hepatectomies (0.4%) and 3 near-miss events (0.6%) were encountered. Maximal effort should be applied to donor selection and operation for donor safety. Copyright © 2016 Elsevier Inc. All rights reserved.

Laparoscopic donor nephrectomy increases the supply of living donor kidneys: a center-specific microeconomic analysis.

PubMed

Kuo, P C; Johnson, L B

2000-05-27

A tenet of microeconomics is that new technology will shift the supply curve to the right. Laparoscopic donor nephrectomy (LDN) is a new technique for removal of living donor kidneys. Centers performing this procedure have noted an increased number of patients presenting for donor evaluation. This has not been previously studied. The records of all LDN performed from May 1998 to February 1999 were reviewed. The following variables were examined: sex, age, related vs. unrelated donation, estimated blood loss, i.v. analgesia, length of stay, and time out of work. Donors undergoing traditional open donor nephrectomy during January 1997 to May 1998 served as the control group. A composite cost index was constructed. LDN significantly decreased length of stay, pain, and time out of work; the supply function shifted to the right. Telephone interviews revealed that 47% donated solely because of the LDN procedure. LDN increases the supply of living donor kidneys.

The cost-effectiveness of using payment to increase living donor kidneys for transplantation.

PubMed

Barnieh, Lianne; Gill, John S; Klarenbach, Scott; Manns, Braden J

2013-12-01

For eligible candidates, transplantation is considered the optimal treatment compared with dialysis for patients with ESRD. The growing number of patients with ESRD requires new strategies to increase the pool of potential donors. Using decision analysis modeling, this study compared a strategy of paying living kidney donors to waitlisted recipients on dialysis with the current organ donation system. In the base case estimate, this study assumed that the number of donors would increase by 5% with a payment of $10,000. Quality of life estimates, resource use, and costs (2010 Canadian dollars) were based on the best available published data. Compared with the current organ donation system, a strategy of increasing the number of kidneys for transplantation by 5% by paying living donors $10,000 has an incremental cost-savings of $340 and a gain of 0.11 quality-adjusted life years. Increasing the number of kidneys for transplantation by 10% and 20% would translate into incremental cost-savings of $1640 and $4030 and incremental quality-adjusted life years gain of 0.21 and 0.39, respectively. Although the impact is uncertain, this model suggests that a strategy of paying living donors to increase the number of kidneys available for transplantation could be cost-effective, even with a transplant rate increase of only 5%. Future work needs to examine the feasibility, legal policy, ethics, and public perception of a strategy to pay living donors.

Emerging infectious disease outbreaks: estimating disease risk in Australian blood donors travelling overseas.

PubMed

Coghlan, A; Hoad, V C; Seed, C R; Flower, R Lp; Harley, R J; Herbert, D; Faddy, H M

2018-01-01

International travel assists spread of infectious pathogens. Australians regularly travel to South-eastern Asia and the isles of the South Pacific, where they may become infected with infectious agents, such as dengue (DENV), chikungunya (CHIKV) and Zika (ZIKV) viruses that pose a potential risk to transfusion safety. In Australia, donors are temporarily restricted from donating for fresh component manufacture following travel to many countries, including those in this study. We aimed to estimate the unmitigated transfusion-transmission (TT) risk from donors travelling internationally to areas affected by emerging infectious diseases. We used the European Up-Front Risk Assessment Tool, with travel and notification data, to estimate the TT risk from donors travelling to areas affected by disease outbreaks: Fiji (DENV), Bali (DENV), Phuket (DENV), Indonesia (CHIKV) and French Polynesia (ZIKV). We predict minimal risk from travel, with the annual unmitigated risk of an infected component being released varying from 1 in 1·43 million to <1 in one billion and the risk of severe consequences ranging from 1 in 130 million to <1 in one billion. The predicted unmitigated likelihood of infection in blood components manufactured from donors travelling to the above-mentioned areas was very low, with the possibility of severe consequences in a transfusion recipient even smaller. Given the increasing demand for plasma products in Australia, the current strategy of restricting donors returning from select infectious disease outbreak areas to source plasma collection provides a simple and effective risk management approach. © 2017 International Society of Blood Transfusion.

Nomograms for predicting graft function and survival in living donor kidney transplantation based on the UNOS Registry.

PubMed

Tiong, H Y; Goldfarb, D A; Kattan, M W; Alster, J M; Thuita, L; Yu, C; Wee, A; Poggio, E D

2009-03-01

We developed nomograms that predict transplant renal function at 1 year (Modification of Diet in Renal Disease equation [estimated glomerular filtration rate]) and 5-year graft survival after living donor kidney transplantation. Data for living donor renal transplants were obtained from the United Network for Organ Sharing registry for 2000 to 2003. Nomograms were designed using linear or Cox regression models to predict 1-year estimated glomerular filtration rate and 5-year graft survival based on pretransplant information including demographic factors, immunosuppressive therapy, immunological factors and organ procurement technique. A third nomogram was constructed to predict 5-year graft survival using additional information available by 6 months after transplantation. These data included delayed graft function, any treated rejection episodes and the 6-month estimated glomerular filtration rate. The nomograms were internally validated using 10-fold cross-validation. The renal function nomogram had an r-square value of 0.13. It worked best when predicting estimated glomerular filtration rate values between 50 and 70 ml per minute per 1.73 m(2). The 5-year graft survival nomograms had a concordance index of 0.71 for the pretransplant nomogram and 0.78 for the 6-month posttransplant nomogram. Calibration was adequate for all nomograms. Nomograms based on data from the United Network for Organ Sharing registry have been validated to predict the 1-year estimated glomerular filtration rate and 5-year graft survival. These nomograms may facilitate individualized patient care in living donor kidney transplantation.

[Groupamatic 360 C1 and automated blood donor processing in a transfusion center].

PubMed

Guimbretiere, J; Toscer, M; Harousseau, H

1978-03-01

Automation of donor management flow path is controlled by: --a 3 slip "port a punch" card, --the groupamatic unit with a result sorted out on punch paper tape, --the management computer off line connected to groupamatic. Data tracking at blood collection time is made by punching a card with the donor card used as a master card. Groupamatic performs: --a standard blood grouping with one run for registered donors and two runs for new donors, --a phenotyping with two runs, --a screening of irregular antibodies. Themanagement computer checks the correlation between the data of the two runs or the data of a single run and that of previous file. It updates the data resident in the central file and prints out: --the controls of the different blood group for the red cell panel, --The listing of error messages, --The listing of emergency call up, --The listing of collected blood units when arrived at the blood center, with quantitative and qualitative information such as: number of blood, units collected, donor addresses, etc., --Statistics, --Donor cards, --Diplomas.

The use of asymmetrical flow field-flow fractionation with on-line detection in the study of drug retention within liposomal nanocarriers and drug transfer kinetics.

PubMed

Hinna, Askell Hvid; Hupfeld, Stefan; Kuntsche, Judith; Brandl, Martin

2016-05-30

Due to their solubilizing capabilities, liposomes (phospholipid vesicles) are suited for designing formulations for intravenous administration of drug compounds which are poorly water-soluble. Despite the good in-vitro stability of such formulations with minimal drug leakage, upon i.v. injection there is a risk of premature drug loss due to drug transfer to plasma proteins and cell membranes. Here we report on the refinement of a recently introduced simple in vitro predictive tool by Hinna and colleagues in 2014, which brings small drug loaded (donor) liposomes in contact with large acceptor liposomes, the latter serving as a model mimicking biological sinks in the body. The donor- and acceptor-liposomes were subsequently separated using asymmetrical flow field-flow fractionation (AF4), during which the sample is exposed to a large volume of eluent which corresponds to a dilution factor of approximately 600. The model drug content in the donor- and acceptor fraction was quantified by on-line UV/VIS extinction measurements with correction for turbidity and by off-line HPLC measurements of collected fractions. The refined method allowed for (near) baseline separation of donor and acceptor vesicles as well as reliable quantification of the drug content not only of the donor- but now also of the acceptor-liposomes due to their improved size-homogeneity, colloidal stability and reduced turbidity. This improvement over the previously reported approach allowed for simultaneous quantification of both drug transfer and drug release to the aqueous phase. By sampling at specific incubation times, the release and transfer kinetics of the model compound p-THPP (5,10,15,20-tetrakis(4-hydroxyphenyl)21H,23H-porphine) was determined. p-THPP is structurally closely related to the photosensitizer temoporfin, which is in clinical use and under evaluation in liposomal formulations. The transfer of p-THPP to the acceptor vesicles followed 1st order kinetics with a half-life of approximately 300 min. As expected, equilibrium distribution between donor- and acceptor vesicles was proportional to the lipid mass ratio. An initial rapid transfer of p-THPP was found (∼ 5%) and investigated further by determining the extent of transfer between donor and acceptor during separation. The donor- and acceptor phase were found to be separated within few minutes and only minor (≤ 2%) transfer could be detected within the AF4 channel under the conditions applied for fractionation. These results demonstrates the potential of our AF4 based method as an in vitro tool to determine retention properties of lipophilic compounds within liposomal carriers in particular, but also within a variety of nano-particulate carriers provided that they exhibit a sufficient size difference compared to the applied colloidal acceptor phase. Copyright © 2016 Elsevier B.V. All rights reserved.

Description of 15 DNA-positive and antibody-negative "window-period" blood donations identified during prospective screening for Babesia microti.

PubMed

Moritz, Erin D; Tonnetti, Laura; Hewins, Mary Ellen; Berardi, Victor P; Dodd, Roger Y; Stramer, Susan L

2017-07-01

Blood donation screening detecting only antibodies fails to identify donors in the earliest stage of infection, before a detectable immunologic response, that is, the "window period" (WP). We present data on WP donations identified during prospective screening for Babesia microti, a transfusion-transmissible parasite of increasing concern in the United States. Blood donations collected in Connecticut, Massachusetts, Minnesota, and Wisconsin were screened using polymerase chain reaction (PCR) and arrayed fluorescence immunoassay (AFIA) to detect B. microti DNA and antibodies, respectively. Parasite loads were estimated using quantitative PCR. Red blood cell (RBC) samples were inoculated into hamsters to assess infectivity. Donors screening reactive were indefinitely deferred, tested by supplemental methods, and followed to assess DNA and antibody clearance. Demographic data from WP donors (i.e., those screening PCR positive and AFIA negative) were compared to data from other positive donors. Of 220,479 donations screened from June 2012 to August 2016, a total of 700 were positive, of which 15 (2% of positive donations or 1 per 14,699 screened donations) were confirmed WP donations. The median estimated parasite load in WP donations was 350 parasites/mL, no different than AFIA-positive and PCR-positive donors. Parasite loads in RBC samples from WP units ranged from 14 to 11,022 parasites/mL; RBC samples from three of 10 (30%) WP donations infected hamsters. The mean age of WP donors was 48 years (range, 17-75 years); three (20%) were female. WP donor demographics did not differ significantly from demographics of other donors. We report one per 15,000 B. microti WP infections in blood donors in endemic areas, demonstrating the importance of nucleic acid testing to mitigate the risk of transfusion-transmitted babesiosis. © 2017 AABB.

Progress towards malaria control targets in relation to national malaria programme funding

PubMed Central

2013-01-01

Background Malaria control has been dramatically scaled up the past decade, mainly thanks to increasing international donor financing since 2003. This study assessed progress up to 2010 towards global malaria impact targets, in relation to Global Fund, other donor and domestic malaria programme financing over 2003 to 2009. Methods Assessments used domestic malaria financing reported by national programmes, and Global Fund/OECD data on donor financing for 90 endemic low- and middle-income countries, WHO estimates of households owning one or more insecticide-treated mosquito net (ITN) for countries in sub-Saharan Africa, and WHO-estimated malaria case incidence and deaths in countries outside sub-Saharan Africa. Results Global Fund and other donor funding is concentrated in a subset of the highest endemic African countries. Outside Africa, donor funding is concentrated in those countries with highest malaria mortality and case incidence rates over the years 2000 to 2003. ITN coverage in 2010 in Africa, and declines in case and death rates per person at risk over 2004 to 2010 outside Africa, were greatest in countries with highest donor funding per person at risk, and smallest in countries with lowest donor malaria funding per person at risk. Outside Africa, all-source malaria programme funding over 2003 to 2009 per case averted ($56-5,749) or per death averted ($58,000-3,900,000) over 2004 to 2010 tended to be lower (more favourable) in countries with higher donor malaria funding per person at risk. Conclusions Increases in malaria programme funding are associated with accelerated progress towards malaria control targets. Associations between programme funding per person at risk and ITN coverage increases and declines in case and death rates suggest opportunities to maximize the impact of donor funding, by strategic re-allocation to countries with highest continued need. PMID:23317000

HIV+ deceased donor referrals: A national survey of organ procurement organizations.

PubMed

Cash, Ayla; Luo, Xun; Chow, Eric K H; Bowring, Mary Grace; Shaffer, Ashton A; Doby, Brianna; Wickliffe, Corey E; Alexander, Charles; McRann, Deborah; Tobian, Aaron A R; Segev, Dorry L; Durand, Christine M

2018-02-01

HIV-infected (HIV+) donor organs can be transplanted into HIV+ recipients under the HIV Organ Policy Equity (HOPE) Act. Quantifying HIV+ donor referrals received by organ procurement organizations (OPOs) is critical for HOPE Act implementation. We surveyed the 58 USA OPOs regarding HIV+ referral records and newly discovered HIV+ donors. Using data from OPOs that provided exact records and CDC HIV prevalence data, we projected a national estimate of HIV+ referrals. Fifty-five (95%) OPOs reported HIV+ referrals ranging from 0 to 276 and newly discovered HIV+ cases ranging from 0 to 10 annually. Six OPOs in areas of high HIV prevalence reported more than 100 HIV+ donor referrals. Twenty-seven (47%) OPOs provided exact HIV+ referral records and 28 (51%) OPOs provided exact records of discovered HIV+ cases, totaling 1450 HIV+ referrals and 39 discovered HIV+ donors in the prior year. These OPOs represented 67% and 59% of prevalent HIV cases in the USA; thus, we estimated 2164 HIV+ referrals and 66 discovered HIV+ cases nationally per year. OPOs reported a high volume of HIV+ referrals annually, of which a subset will be medically eligible for donation. Particularly in areas of high HIV prevalence, OPOs require ongoing support to implement the HOPE Act. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Methodological considerations in the interpretation of serologic screening for hepatitis B virus among blood donors].

PubMed

Martelli, C M; de Andrade, A L; das Dores, D; Cardoso, P; Almeida e Silva, S; Zicker, F

1991-02-01

Between October 1988 and February 1989, 1,033 voluntary first-time blood donors were screened for hepatitis B infection in five blood banks in Goiâna, Central Brazil. The survey was part of a major study designed to estimate seroprevalence of HBsAg and anti-HBs and to discuss methodological issues related to prevalence estimation based on data from blood banks. Donors were interviewed and blood samples were collected and tested for HBsAg and anti-HBs by ELISA tests. Prevalences of 1.9% and 10.9% were obtained for HBsAg and anti-HBs, respectively, and no statistical difference was found between the sexes. Prevalence of anti-HBs increased with age (X2 for trend = 7.9 p = 0.004). The positive predictive value and sensitivity of history of jaundice or hepatitis reported in the interview in detecting seropositives were 13.6% and 2.2%, respectively. The methodological issues, including internal and external validity of HBV prevalence estimated among blood donors are discussed. The potential usefulness of blood banks as a source of morbidity information for surveillance for Hepatitis B virus infection is stressed.

Light-scattering flow cytometry for identification and characterization of blood microparticles

NASA Astrophysics Data System (ADS)

Konokhova, Anastasiya I.; Yurkin, Maxim A.; Moskalensky, Alexander E.; Chernyshev, Andrei V.; Tsvetovskaya, Galina A.; Chikova, Elena D.; Maltsev, Valeri P.

2012-05-01

We describe a novel approach to study blood microparticles using the scanning flow cytometer, which measures light scattering patterns (LSPs) of individual particles. Starting from platelet-rich plasma, we separated spherical microparticles from non-spherical plasma constituents, such as platelets and cell debris, based on similarity of their LSP to that of sphere. This provides a label-free method for identification (detection) of microparticles, including those larger than 1 μm. Next, we rigorously characterized each measured particle, determining its size and refractive index including errors of these estimates. Finally, we employed a deconvolution algorithm to determine size and refractive index distributions of the whole population of microparticles, accounting for largely different reliability of individual measurements. Developed methods were tested on a blood sample of a healthy donor, resulting in good agreement with literature data. The only limitation of this approach is size detection limit, which is currently about 0.5 μm due to used laser wavelength of 0.66 μm.

Kidney transplantation after desensitization in sensitized patients: a Korean National Audit.

PubMed

Huh, Kyu Ha; Kim, Beom Seok; Yang, Jaeseok; Ahn, Jeongmyung; Kim, Myung-Gyu; Park, Jae Berm; Kim, Jong Man; Chung, Byung-Ha; Kim, Joong Kyung; Kong, Jin Min

2012-10-01

The number of end-stage renal disease (ESRD) patients with preformed antibodies waiting for a kidney transplant has been increasing lately. We conducted a nationwide study on the outcomes of kidney transplantation after desensitization in Korea. Six transplant centers have run desensitization programs. The patients who underwent living donor kidney transplantation after desensitization from 2002 to 2010 were retrospectively analyzed. A total of 86 cases were enrolled. Thirty-five of these were cases of re-transplantation (40.7 %). Indications of desensitization were positive complement-dependent cytotoxicity (CDC) cross-match responses (CDC(+), 36.0 %), positive flow-cytometric cross-match responses (FCX(+), 54.7 %), and positive donor-specific antibodies (DSA(+), 8.1 %). The desensitization protocols used pre-transplant plasmapheresis (95.3 %), intravenous immunoglobulin (62.8 %), and rituximab (67.4 %). Acute rejection occurred in 18 patients (20.9 %), graft failure occurred in 4 patients, and the 3-year graft survival rate was 93.8 %. The presence of DSA increased the acute rejection rate (P = 0.015) and decreased the 1-year post-transplant estimated glomerular filtration rate (P = 0.006). Although rejection-free survival rates did not differ significantly between the CDC(+) and FCX(+) groups, the 1-year estimated glomerular filtration rate was lower in the CDC(+) group (P = 0.010). Infectious and significant bleeding complications occurred in 15.5 % and 4.7 % of cases, respectively. Kidney transplantation after desensitization had good graft outcomes and tolerable complications in Korea, and therefore, this therapy can be recommended for sensitized ESRD patients.

Estimating the Risk of Parvovirus B19 Infection in Blood Donors and Pregnant Women in Japan

PubMed Central

Nabae, Koji; Satoh, Hiroshi; Nishiura, Hiroshi; Tanaka-Taya, Keiko; Okabe, Nobuhiko; Oishi, Kazunori; Matsumoto, Kunichika; Hasegawa, Tomonori

2014-01-01

Background Seroepidemiological study of parvovirus B19 has not taken place for some 20 years in Japan. To estimate the risk of parvovirus B19 infection in Japan among blood donors and pregnant women in this century, a seroepidemiological survey and statistical modeling of the force of infection were conducted. Methodology/Principal Findings The time- and age-specific seroprevalence data were suggestive of strong age-dependency in the risk of infection. Employing a piecewise constant model, the highest forces of infection of 0.05 and 0.12 per year were observed among those aged 0–4 and 5–9 years, respectively, while estimates among older individuals were less than 0.01 per year. Analyzing the antigen detection data among blood donors, the age-specific proportion positive was highest among those aged 30–39 years, agreeing with the presence of dip in seroprevalence in this age-group. Among pregnant women, up to 107 fetal deaths and 21 hydrops fetalis were estimated to have occurred annually across Japan. Conclusions Seroepidemiological profiles of PVB19 infection in Japan was characterized with particular emphasis on the risk of infection in blood donors and the burden of infection among pregnant women. When a vaccine becomes available in the future, a similar seroepidemiological study is expected to play a key role in planning the appropriate immunization policy. PMID:24658180

[Banff score changes in kidneys from marginal donors].

PubMed

Borda, Bernadett; Szederkényi, Edit; Ottlakán, Aurél; Kemény, Éva; Szabó, Viktor; Hódi, Zoltán; Lázár, György

2016-02-21

Despite an increase in the number of cadaver donors and the number of overall organ transplantations, the dramatic increase in the waiting list makes it necessary to reconsider donor criteria. The authors examined whether differences could exist in the function and/or morphology of transplanted kidneys originated from marginal and ideal donors one and five years after transplantation. Kidney function and histopathologic findings were analysed and compared one and 5 years after transplantation in 97 patients having marginal donor kidneys and 178 patients who received ideal donor kidneys. Serum creatinine level was significantly higher (p = 0.0001) and estimated glomerular filtration rate was significantly lower (p = 0.003) in patients having marginal donor kidneys as compared to those with ideal donor kidneys 5 years after transplantation. Morphological changes in the transplanted kidneys such as tubulitis (p = 0.014) and interstitial inflammation (p = 0.025) were significantly more frequently present in patients with marginal donor kidneys than in those with ideal donor kidneys one year after transplantation. Despite an absence of differences in kidney function one year after kidney transplantation between patients having marginal and ideal donor kidneys, morphologic differences in the transplanted kidneys can be detected between the two groups of patients.

Estimation of electronic coupling in π-stacked donor-bridge-acceptor systems: Correction of the two-state model

NASA Astrophysics Data System (ADS)

Voityuk, Alexander A.

2006-02-01

Comparison of donor-acceptor electronic couplings calculated within two-state and three-state models suggests that the two-state treatment can provide unreliable estimates of Vda because of neglecting the multistate effects. We show that in most cases accurate values of the electronic coupling in a π stack, where donor and acceptor are separated by a bridging unit, can be obtained as Ṽda=(E2-E1)μ12/Rda+(2E3-E1-E2)2μ13μ23/Rda2, where E1, E2, and E3 are adiabatic energies of the ground, charge-transfer, and bridge states, respectively, μij is the transition dipole moments between the states i and j, and Rda is the distance between the planes of donor and acceptor. In this expression based on the generalized Mulliken-Hush approach, the first term corresponds to the coupling derived within a two-state model, whereas the second term is the superexchange correction accounting for the bridge effect. The formula is extended to bridges consisting of several subunits. The influence of the donor-acceptor energy mismatch on the excess charge distribution, adiabatic dipole and transition moments, and electronic couplings is examined. A diagnostic is developed to determine whether the two-state approach can be applied. Based on numerical results, we showed that the superexchange correction considerably improves estimates of the donor-acceptor coupling derived within a two-state approach. In most cases when the two-state scheme fails, the formula gives reliable results which are in good agreement (within 5%) with the data of the three-state generalized Mulliken-Hush model.

Estimation of electronic coupling in pi-stacked donor-bridge-acceptor systems: correction of the two-state model.

PubMed

Voityuk, Alexander A

2006-02-14

Comparison of donor-acceptor electronic couplings calculated within two-state and three-state models suggests that the two-state treatment can provide unreliable estimates of V(da) because of neglecting the multistate effects. We show that in most cases accurate values of the electronic coupling in a pi stack, where donor and acceptor are separated by a bridging unit, can be obtained as V(da) = (E(2)-E(1))mu(12)R(da) + (2E(3)-E(1)-E(2))2mu(13)mu(23)R(da) (2), where E(1), E(2), and E(3) are adiabatic energies of the ground, charge-transfer, and bridge states, respectively, mu(ij) is the transition dipole moments between the states i and j, and R(da) is the distance between the planes of donor and acceptor. In this expression based on the generalized Mulliken-Hush approach, the first term corresponds to the coupling derived within a two-state model, whereas the second term is the superexchange correction accounting for the bridge effect. The formula is extended to bridges consisting of several subunits. The influence of the donor-acceptor energy mismatch on the excess charge distribution, adiabatic dipole and transition moments, and electronic couplings is examined. A diagnostic is developed to determine whether the two-state approach can be applied. Based on numerical results, we showed that the superexchange correction considerably improves estimates of the donor-acceptor coupling derived within a two-state approach. In most cases when the two-state scheme fails, the formula gives reliable results which are in good agreement (within 5%) with the data of the three-state generalized Mulliken-Hush model.

Incidence and Residual Risk of HIV, HBV and HCV Infections Among Blood Donors in Tehran.

PubMed

Saber, Hamid Reza; Tabatabaee, Seyed Morteza; Abasian, Ali; Jamali, Mostafa; SalekMoghadam, Ebadollah; Hajibeigi, Bashir; Alavian, Seyed Moayed; Mirrezaie, Seyed Mohammad

2017-09-01

Estimation of residual risk is essential to monitor and improve blood safety. Our epidemiologic knowledge in the Iranian donor population regarding transfusion transmitted viral infections (TTIs), is confined to a few studies based on prevalence rate. There are no reports on residual risk of TTIs in Iran. In present survey, a software database of donor records of Tehran Blood Transfusion Center (TBTC) was used to estimate the incidence and residual risk of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections, by applying the incidence rate/window period (IR-WP) model. A total of 1,207,155 repeat donations was included in the analysis and represented a mean of 8.4 donations per donor over 6 years. The incidence amongst repeat donors was estimated by dividing the number of confirmed seroconverting donors by the total number of person-years at risk. The residual risk was calculated using the incidence/window period model. Incidence rate and residual risk for HBV, HCV and HIV infections were calculated for total (2005-2010) and two consecutive periods (2005-2007 and 2008-2010) of the study. According to the IR-WP model, overall residual risk for HIV and HCV in the total study period was 0.4 and 12.5 per million units, respectively and for HBV 4.57/100,000 donations. The incidence and residual risk of TTIs, calculated on TBTC's blood supply was low and comparable with developed countries for HIV infection but high for HCV and HBV infections. Blood safety may therefore be better managed by applying other techniques like nucleic acid amplification tests.

The Cost-Effectiveness of Using Payment to Increase Living Donor Kidneys for Transplantation

PubMed Central

Barnieh, Lianne; Gill, John S.; Klarenbach, Scott

2013-01-01

Summary Background and objectives For eligible candidates, transplantation is considered the optimal treatment compared with dialysis for patients with ESRD. The growing number of patients with ESRD requires new strategies to increase the pool of potential donors. Design, setting, participants, & measurements Using decision analysis modeling, this study compared a strategy of paying living kidney donors to waitlisted recipients on dialysis with the current organ donation system. In the base case estimate, this study assumed that the number of donors would increase by 5% with a payment of $10,000. Quality of life estimates, resource use, and costs (2010 Canadian dollars) were based on the best available published data. Results Compared with the current organ donation system, a strategy of increasing the number of kidneys for transplantation by 5% by paying living donors $10,000 has an incremental cost-savings of $340 and a gain of 0.11 quality-adjusted life years. Increasing the number of kidneys for transplantation by 10% and 20% would translate into incremental cost-savings of $1640 and $4030 and incremental quality-adjusted life years gain of 0.21 and 0.39, respectively. Conclusion Although the impact is uncertain, this model suggests that a strategy of paying living donors to increase the number of kidneys available for transplantation could be cost-effective, even with a transplant rate increase of only 5%. Future work needs to examine the feasibility, legal policy, ethics, and public perception of a strategy to pay living donors. PMID:24158797

Risk for transfusion-transmitted infectious diseases in Central and South America.

PubMed

Schmunis, G A; Zicker, F; Pinheiro, F; Brandling-Bennett, D

1998-01-01

We report the potential risk for an infectious disease through tainted transfusion in 10 countries of South and Central America in 1993 and in two countries of South America in 1994, as well as the cost of reagents as partial estimation of screening costs. Of the 12 countries included in the study, nine screened all donors for HIV; three screened all donors for hepatitis B virus (HBV); two screened all donors for Trypanosoma cruzi; none screened all donors for hepatitis C virus (HCV); and six screened some donors for syphilis. Estimates of the risk of acquiring HIV through blood transfusion were much lower than for acquiring HBV, HCV, or T. cruzi because of significantly higher screening and lower prevalence.rates for HIV. An index of infectious disease spread through blood transfusion was calculated for each country. The highest value was obtained for Bolivia (233 infections per 10,000 transfusions); in five other countries, it was 68 to 103 infections per 10,000. The risks were lower in Honduras (nine per 10,000), Ecuador (16 per 10,000), and Paraguay (19 per 10,000). While the real number of potentially infected units or infected persons is probably lower than our estimates because of false positives and already infected recipients, the data reinforce the need for an information system to assess the level of screening for infectious diseases in the blood supply. Since this information was collected, Chile, Colombia, Costa Rica, and Venezuela have made HCV screening mandatory; serologic testing for HCV has increased in those countries, as well as in El Salvador and Honduras. T. cruzi screening is now mandatory in Colombia, and the percentage of screened donors increased not only in Colombia, but also in Ecuador, El Salvador, and Paraguay. Laws to regulate blood transfusion practices have been enacted in Bolivia, Guatemala, and Peru. However, donor screening still needs to improve for one or more diseases in most countries.

Risk for transfusion-transmitted infectious diseases in Central and South America.

PubMed Central

Schmunis, G. A.; Zicker, F.; Pinheiro, F.; Brandling-Bennett, D.

1998-01-01

We report the potential risk for an infectious disease through tainted transfusion in 10 countries of South and Central America in 1993 and in two countries of South America in 1994, as well as the cost of reagents as partial estimation of screening costs. Of the 12 countries included in the study, nine screened all donors for HIV; three screened all donors for hepatitis B virus (HBV); two screened all donors for Trypanosoma cruzi; none screened all donors for hepatitis C virus (HCV); and six screened some donors for syphilis. Estimates of the risk of acquiring HIV through blood transfusion were much lower than for acquiring HBV, HCV, or T. cruzi because of significantly higher screening and lower prevalence.rates for HIV. An index of infectious disease spread through blood transfusion was calculated for each country. The highest value was obtained for Bolivia (233 infections per 10,000 transfusions); in five other countries, it was 68 to 103 infections per 10,000. The risks were lower in Honduras (nine per 10,000), Ecuador (16 per 10,000), and Paraguay (19 per 10,000). While the real number of potentially infected units or infected persons is probably lower than our estimates because of false positives and already infected recipients, the data reinforce the need for an information system to assess the level of screening for infectious diseases in the blood supply. Since this information was collected, Chile, Colombia, Costa Rica, and Venezuela have made HCV screening mandatory; serologic testing for HCV has increased in those countries, as well as in El Salvador and Honduras. T. cruzi screening is now mandatory in Colombia, and the percentage of screened donors increased not only in Colombia, but also in Ecuador, El Salvador, and Paraguay. Laws to regulate blood transfusion practices have been enacted in Bolivia, Guatemala, and Peru. However, donor screening still needs to improve for one or more diseases in most countries. PMID:9452393

Current–voltage characteristics of organic heterostructure devices with insulating spacer layers

DOE PAGES

Yin, Sun; Nie, Wanyi; Mohite, Aditya D.; ...

2015-05-14

The dark current density in donor/acceptor organic planar heterostructure devices at a given forward voltage bias can either increase or decrease when an insulating spacer layer is added between the donor and acceptor layers. The dominant current flow process in these systems involves the formation and subsequent recombination of interfacial exciplex states. If the exciplex recombination rate limits current flow, an insulating interface layer decreases the dark current. However, if the exciplex formation rate limits the current, an insulating interface layer may increase the dark current. As a result, we present a device model to describe this behavior, and wemore » discuss relevant experimental data.« less

Individual, contextual and network characteristics of blood donors and non-donors: a systematic review of recent literature

PubMed Central

Piersma, Tjeerd W.; Bekkers, René; Klinkenberg, Elisabeth F.; de Kort, Wim L.A.M.; Merz, Eva-Maria

2017-01-01

Background The ageing population and recent migration flows may negatively affect the blood supply in the long term, increasing the importance of targeted recruitment and retention strategies to address donors. This review sought to identify individual, network and contextual characteristics related to blood donor status and behaviour, to systematically discuss differences between study results, and to identify possible factors to target in recruitment and retention efforts. Methods The systematic review was conducted in accordance with a predefined PROSPERO protocol (CRD42016039591). After quality assessments by multiple independent raters, a final set of 66 peer-reviewed papers, published between October 2009 and January 2017, were included for review. Results Individual and contextual characteristics of blood donor status and behaviour were categorised into five main lines of research: donor demographics, motivations and barriers, adverse reactions and deferral, contextual factors, and blood centre factors. Results on donor demographics, motivations and barriers, and contextual factors were inconclusive, differing between studies, countries, and sample characteristics. Adverse reactions and deferral were negatively related to blood donor behaviour. Blood centre factors play an important role in donor management, e.g., providing information, reminders, and (non-)monetary rewards. No studies were found on network characteristics of (non-)donors. Discussion Although individual and contextual characteristics strongly relate to blood donor status and behaviour, mechanisms underlying these relations have not been studied sufficiently. We want to stress the importance of longitudinal studies in donor behaviour, exploring the role of life events and network characteristics within blood donor careers. Increased understanding of donor behaviour will assist policy makers of blood collection agencies, with the ultimate goal of safeguarding a sufficient and matching blood supply. PMID:28686151

Individual, contextual and network characteristics of blood donors and non-donors: a systematic review of recent literature.

PubMed

Piersma, Tjeerd W; Bekkers, René; Klinkenberg, Elisabeth F; De Kort, Wim L A M; Merz, Eva-Maria

2017-09-01

The ageing population and recent migration flows may negatively affect the blood supply in the long term, increasing the importance of targeted recruitment and retention strategies to address donors. This review sought to identify individual, network and contextual characteristics related to blood donor status and behaviour, to systematically discuss differences between study results, and to identify possible factors to target in recruitment and retention efforts. The systematic review was conducted in accordance with a predefined PROSPERO protocol (CRD42016039591). After quality assessments by multiple independent raters, a final set of 66 peer-reviewed papers, published between October 2009 and January 2017, were included for review. Individual and contextual characteristics of blood donor status and behaviour were categorised into five main lines of research: donor demographics, motivations and barriers, adverse reactions and deferral, contextual factors, and blood centre factors. Results on donor demographics, motivations and barriers, and contextual factors were inconclusive, differing between studies, countries, and sample characteristics. Adverse reactions and deferral were negatively related to blood donor behaviour. Blood centre factors play an important role in donor management, e.g., providing information, reminders, and (non-)monetary rewards. No studies were found on network characteristics of (non-)donors. Although individual and contextual characteristics strongly relate to blood donor status and behaviour, mechanisms underlying these relations have not been studied sufficiently. We want to stress the importance of longitudinal studies in donor behaviour, exploring the role of life events and network characteristics within blood donor careers. Increased understanding of donor behaviour will assist policy makers of blood collection agencies, with the ultimate goal of safeguarding a sufficient and matching blood supply.

Human immunodeficiency virus prevalence, incidence, and residual transmission risk in first-time and repeat blood donations in Zimbabwe: implications on blood safety.

PubMed

Mapako, Tonderai; Mvere, David A; Chitiyo, McLeod E; Rusakaniko, Simbarashe; Postma, Maarten J; van Hulst, Marinus

2013-10-01

National Blood Service Zimbabwe human immunodeficiency virus (HIV) risk management strategy includes screening and discarding of first-time donations, which are collected in blood packs without an anticoagulant (dry pack). To evaluate the impact of discarding first-time donations on blood safety the HIV prevalence, incidence, and residual risk in first-time and repeat donations (wet packs) were compared. Donor data from 2002 to 2010 were retrieved from a centralized national electronic donor database and retrospectively analyzed. Chi-square test was used to compare HIV prevalence with relative risk (RR), and the RR point estimates and 95% confidence interval (CI) are reported. Trend analysis was done using Cochran-Armitage trend test. HIV residual risk estimates were determined using published residual risk estimation models. Over the 9 years the overall HIV prevalence estimates are 1.29% (n = 116,058) and 0.42% (n = 434,695) for first-time and repeat donations, respectively. The overall RR was 3.1 (95% CI, 2.9-3.3; p < 0.0001). The overall mean residual transmission risk of HIV window phase donations in first-time was 1:7384 (range, 1:11,308-1:5356) and in repeat donors it was 1:5496 (range, 1:9943-1:3347). The significantly high HIV prevalence estimates recorded in first-time over repeat donations is indicative of the effectiveness of the HIV risk management strategy. However, comparable residual transmission risk estimates in first-time and repeat donors point to the need to further review the risk management strategies. Given the potential wastage of valuable resources, future studies should focus on the cost-effectiveness and utility of screening and discarding first-time donations. © 2013 American Association of Blood Banks.

Short communication: Genetic correlations between number of embryos produced using in vivo and in vitro techniques in heifer and cow donors.

PubMed

Jaton, C; Koeck, A; Sargolzaei, M; Price, C A; Baes, C; Schenkel, F S; Miglior, F

2016-10-01

Multiple embryos can be produced from a heifer or cow donors using an in vivo or an in vitro technique. Comparisons of the number of embryos produced by the same donors as heifers and cows and using different techniques are limited. The main objectives of this study were to assess the genetic correlation between the number of embryos produced by Holstein donors using an in vivo and in vitro technique as a heifer and as a cow. The data set used was recorded by Holstein Canada and included all successful superovulations or ovum pickup and in vitro fertilization procedures performed on Holstein donors for more than 20yr. The type of technique used was known for all records and the status of the donor at recovery was retrieved from calving records. Bivariate repeatability animal model analyses were performed for both the total number of embryos (NE) and the number of viable embryos (VE) recovered per procedure. Logarithmic transformation was performed on the traits to normalize the data. Heritability estimates for the donor varied between 0.14 (0.02) and 0.19 (0.03) over all analyses, indicating that the number of embryos produced by a donor is influenced by the genetic potential of the donor. Genetic correlations between records produced in vivo and in vitro were moderately high and positive (NE=0.85±0.07; VE=0.63±0.09), suggesting that donors with high genetic potential for in vivo superovulation tend also to have high potential to produce multiple embryos in vitro. Similarly, the moderately high genetic correlations (NE=0.79±0.05; VE=0.72±0.05) found between heifer and cow records indicate that a donor tends to produce a comparable number of embryos as a heifer or as a cow. The estimated repeatabilities (0.23 to 0.35) indicated that the number of embryos recovered should be somewhat repeatable in the same donor over time. On the other hand, the service sires seem not to play an important role on the total number of embryos produced by a donor no matter the technique used or the status of the donor at recovery. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Pollen-mediated gene flow from glyphosate-resistant common waterhemp (Amaranthus rudis Sauer): consequences for the dispersal of resistance genes

PubMed Central

Sarangi, Debalin; Tyre, Andrew J.; Patterson, Eric L.; Gaines, Todd A.; Irmak, Suat; Knezevic, Stevan Z.; Lindquist, John L.; Jhala, Amit J.

2017-01-01

Gene flow is an important component in evolutionary biology; however, the role of gene flow in dispersal of herbicide-resistant alleles among weed populations is poorly understood. Field experiments were conducted at the University of Nebraska-Lincoln to quantify pollen-mediated gene flow (PMGF) from glyphosate-resistant (GR) to -susceptible (GS) common waterhemp using a concentric donor-receptor design. More than 130,000 common waterhemp plants were screened and 26,199 plants were confirmed resistant to glyphosate. Frequency of gene flow from all distances, directions, and years was estimated with a double exponential decay model using Generalized Nonlinear Model (package gnm) in R. PMGF declined by 50% at <3 m distance from the pollen source, whereas 90% reduction was found at 88 m (maximum) depending on the direction of the pollen-receptor blocks. Amplification of the target site gene, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), was identified as the mechanism of glyphosate resistance in parent biotype. The EPSPS gene amplification was heritable in common waterhemp and can be transferred via PMGF, and also correlated with glyphosate resistance in pseudo-F2 progeny. This is the first report of PMGF in GR common waterhemp and the results are critical in explaining the rapid dispersal of GR common waterhemp in Midwestern United States. PMID:28327669

The Effect of Acceptor and Donor Doping on Oxygen Vacancy Concentrations in Lead Zirconate Titanate (PZT).

PubMed

Slouka, Christoph; Kainz, Theresa; Navickas, Edvinas; Walch, Gregor; Hutter, Herbert; Reichmann, Klaus; Fleig, Jürgen

2016-11-22

The different properties of acceptor-doped (hard) and donor-doped (soft) lead zirconate titanate (PZT) ceramics are often attributed to different amounts of oxygen vacancies introduced by the dopant. Acceptor doping is believed to cause high oxygen vacancy concentrations, while donors are expected to strongly suppress their amount. In this study, La 3+ donor-doped, Fe 3+ acceptor-doped and La 3+ /Fe 3+ -co-doped PZT samples were investigated by oxygen tracer exchange and electrochemical impedance spectroscopy in order to analyse the effect of doping on oxygen vacancy concentrations. Relative changes in the tracer diffusion coefficients for different doping and quantitative relations between defect concentrations allowed estimates of oxygen vacancy concentrations. Donor doping does not completely suppress the formation of oxygen vacancies; rather, it concentrates them in the grain boundary region. Acceptor doping enhances the amount of oxygen vacancies but estimates suggest that bulk concentrations are still in the ppm range, even for 1% acceptor doping. Trapped holes might thus considerably contribute to the charge balancing of the acceptor dopants. This could also be of relevance in understanding the properties of hard and soft PZT.

The Effect of Acceptor and Donor Doping on Oxygen Vacancy Concentrations in Lead Zirconate Titanate (PZT)

PubMed Central

Slouka, Christoph; Kainz, Theresa; Navickas, Edvinas; Walch, Gregor; Hutter, Herbert; Reichmann, Klaus; Fleig, Jürgen

2016-01-01

The different properties of acceptor-doped (hard) and donor-doped (soft) lead zirconate titanate (PZT) ceramics are often attributed to different amounts of oxygen vacancies introduced by the dopant. Acceptor doping is believed to cause high oxygen vacancy concentrations, while donors are expected to strongly suppress their amount. In this study, La3+ donor-doped, Fe3+ acceptor-doped and La3+/Fe3+-co-doped PZT samples were investigated by oxygen tracer exchange and electrochemical impedance spectroscopy in order to analyse the effect of doping on oxygen vacancy concentrations. Relative changes in the tracer diffusion coefficients for different doping and quantitative relations between defect concentrations allowed estimates of oxygen vacancy concentrations. Donor doping does not completely suppress the formation of oxygen vacancies; rather, it concentrates them in the grain boundary region. Acceptor doping enhances the amount of oxygen vacancies but estimates suggest that bulk concentrations are still in the ppm range, even for 1% acceptor doping. Trapped holes might thus considerably contribute to the charge balancing of the acceptor dopants. This could also be of relevance in understanding the properties of hard and soft PZT. PMID:28774067

Estimation of the basicity of the donor strength of terminal groups in cationic polymethine dyes

NASA Astrophysics Data System (ADS)

Kachkovsky, Alexey; Obernikhina, Nataliya; Prostota, Yaroslav; Naumenko, Antonina; Melnyk, Dmitriy; Yashchuk, Valeriy

2018-02-01

The well-known conception of the basicity of the terminal groups in the cationic polymethine dyes showing their donor properties is examined (considered) in detail. The various approachs are proposed to quantitative quantum-chemical estimation of a donor strength of the terminal groups in cationic polymethine dyes: shift of the frontier levels upon introducing terminal residues in comparison with unsybstituted polymethine cation; transferring of the electron density from the terminal groups to the polymethine chain and hence manifested itself as a redistribution of total positive charge between molecular fragments; changes of the charge alternation at carbon atoms along the chain. All approach correlate between them and agree with the concept of the basicity as a capability of terminal heterocycles to show its donor properties in the polymethine dyes. The results of the fulfilled calculations of numerous examples are presented; the proposed parameters point correctly the tendency in the change donor strength upon varying of the chemical constitution: the dimension of cycle, introducing of various heteroatoms, linear or angular annelating by benzene ring; as well as direct to take into consideration the existence of local levels.

Hybrid Donor-Dot Devices made using Top-down Ion Implantation for Quantum Computing

NASA Astrophysics Data System (ADS)

Bielejec, Edward; Bishop, Nathan; Carroll, Malcolm

2012-02-01

We present progress towards fabricating hybrid donor -- quantum dots (QD) for quantum computing. These devices will exploit the long coherence time of the donor system and the surface state manipulation associated with a QD. Fabrication requires detection of single ions implanted with 10's of nanometer precision. We show in this talk, 100% detection efficiency for single ions using a single ion Geiger mode avalanche (SIGMA) detector integrated into a Si MOS QD process flow. The NanoImplanter (nI) a focused ion beam system is used for precision top-down placement of the implanted ion. This machine has a 10 nm resolution combined with a mass velocity filter, allowing for the use of multi-species liquid metal ion sources (LMIS) to implant P and Sb ions, and a fast blanking and chopping system for single ion implants. The combination of the nI and integration of the SIGMA with the MOS QD process flow establishes a path to fabricate hybrid single donor-dot devices. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Determinants of ABH expression on human blood platelets.

PubMed

Cooling, Laura L W; Kelly, Kathleen; Barton, James; Hwang, Debbie; Koerner, Theodore A W; Olson, John D

2005-04-15

Platelets express ABH antigens, which can adversely effect platelet transfusion recovery and survival in ABH-incompatible recipients. To date, there has been no large, comprehensive study comparing specific donor factors with ABH expression on platelet membranes and glycoconjugates. We studied ABH expression in 166 group A apheresis platelet donors by flow cytometry, Western blotting, and thin layer chromatography relative to donor age, sex, A1/A2 subgroup, and Lewis phenotype. Overall, A antigen on platelet membranes, glycoproteins, and glycosphingolipids was linked to an A1 red blood cell (RBC) phenotype. Among A1 donors, platelet ABH varied significantly between donors (0%-87%). Intradonor variability, however, was minimal, suggesting that platelet ABH expression is a stable, donor-specific characteristic, with 5% of A1 donors typing as either ABH high- or low-expressers. Group A2 donors, in contrast, possessed a Bombay-like phenotype, lacking both A and H antigens. Unlike RBCs, ABH expression on platelets may be determined primarily by H-glycosyltransferase (FUT1) activity. Identification of A2 and A1 low expressers may increase the availability and selection of crossmatched and HLA-matched platelets. Platelets from group A2 may also be a superior product for patients undergoing A/O major mismatch allogeneic progenitor cell transplantation.

Uranium reduction and microbial community development in response to stimulation with different electron donors.

PubMed

Barlett, Melissa; Moon, Hee Sun; Peacock, Aaron A; Hedrick, David B; Williams, Kenneth H; Long, Philip E; Lovley, Derek; Jaffe, Peter R

2012-07-01

Stimulating microbial reduction of soluble U(VI) to less soluble U(IV) shows promise as an in situ bioremediation strategy for uranium contaminated groundwater, but the optimal electron donors for promoting this process have yet to be identified. The purpose of this study was to better understand how the addition of various electron donors to uranium-contaminated subsurface sediments affected U(VI) reduction and the composition of the microbial community. The simple electron donors, acetate or lactate, or the more complex donors, hydrogen-release compound (HRC) or vegetable oil, were added to the sediments incubated in flow-through columns. The composition of the microbial communities was evaluated with quantitative PCR probing specific 16S rRNA genes and functional genes, phospholipid fatty acid analysis, and clone libraries. All the electron donors promoted U(VI) removal, even though the composition of the microbial communities was different with each donor. In general, the overall biomass, rather than the specific bacterial species, was the factor most related to U(VI) removal. Vegetable oil and HRC were more effective in stimulating U(VI) removal than acetate. These results suggest that the addition of more complex organic electron donors could be an excellent option for in situ bioremediation of uranium-contaminated groundwater.

Impact of the origin of the collateral feeding donor artery on short-term mortality in ST-elevation myocardial infarction with comorbid chronic total occlusion.

PubMed

Fujii, Toshiharu; Sakai, Katsuaki; Nakano, Masataka; Ohno, Yohei; Nakazawa, Gaku; Shinozaki, Norihiko; Matsukage, Takashi; Yoshimachi, Fuminobu; Ikari, Yuji

2016-09-01

Patients with ST-elevation myocardial infarction (STEMI) and multi-vessel disease (MVD) have higher mortality, especially with comorbid chronic total occlusion (CTO). The origin of collateral flow to the CTO segment has not been studied in regard to short-term mortality. This study examined the impact of collateral feeding donor arteries from an infarct-related artery (IRA) or non-IRA to the comorbid CTO segment in regard to STEMI short-term mortality. Data from 760 consecutive STEMI patients who underwent primary percutaneous coronary intervention were obtained retrospectively from medical records. The number of vessels involved and origin of the collateral feeding donor artery were evaluated using angiograms from the primary percutaneous coronary intervention. The study population was divided into patients with: single-vessel disease (SVD) (n=483), MVD without CTO (n=208), and MVD with CTO (n=64). All CTO segments had collateral flow from an IRA (n=23) or non-IRA (n=46). All-cause mortality (30-day) was analyzed. Compared to SVD and MVD without CTO, MVD with comorbid CTO had a higher mortality (5.4% vs. 15.9% vs. 24.6%, P<0.0001, respectively). Of patients with CTO, those with collateral flow from the IRA had significantly higher mortality than the non-IRA group (52.2% vs. 10.9%, P<0.0001). Collateral flow from the IRA was extracted as an independent predictor associated with 30-day all-cause mortality using a multivariate Cox proportional hazards model (hazard ratio 4.71, 95% confidence interval 1.60-14.2, P=0.0005). The origin of the collateral donor artery from the IRA had an impact on short-term mortality in STEMI patients with comorbid CTO lesions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

CT volumetry is superior to nuclear renography for prediction of residual kidney function in living donors.

PubMed

Barbas, Andrew S; Li, Yanhong; Zair, Murtuza; Van, Julie A; Famure, Olusegun; Dib, Martin J; Laurence, Jerome M; Kim, S Joseph; Ghanekar, Anand

2016-09-01

Living kidney donor evaluation commonly includes nuclear renography to assess split kidney function and computed tomography (CT) scan to evaluate anatomy. To streamline donor workup and minimize exposure to radioisotopes, we sought to assess the feasibility of using proportional kidney volume from CT volumetry in lieu of nuclear renography. We examined the correlation between techniques and assessed their ability to predict residual postoperative kidney function following live donor nephrectomy. In a cohort of 224 live kidney donors, we compared proportional kidney volume derived by CT volumetry with split kidney function derived from nuclear renography and found only modest correlation (left kidney R(2) =26.2%, right kidney R(2) =26.7%). In a subset of 88 live kidney donors with serum creatinine measured 6 months postoperatively, we compared observed estimated glomerular filtration rate (eGFR) at 6 months with predicted eGFR from preoperative imaging. Compared to nuclear renography, CT volumetry more closely approximated actual observed postoperative eGFR for Chronic Kidney Disease Epidemiology Collaboration (J-test: P=.02, Cox-Pesaran test: P=.01) and Mayo formulas (J-test: P=.004, Cox-Pesaran test: P<.001). These observations support the use of CT volumetry for estimation of split kidney function in healthy individuals with normal kidney function and morphology. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Urinary biomarkers of acute kidney injury in deceased organ donors--kidney injury molecule-1 as an adjunct to predicting outcome.

PubMed

Field, Melanie; Dronavalli, Vamsi; Mistry, Punam; Drayson, Mark; Ready, Andrew; Cobbold, Mark; Inston, Nicholas

2014-07-01

Deceased kidney donors are increasingly "marginal," and many have risk factors for acute kidney injury (AKI) that may impact on subsequent renal transplant outcome. Despite this, determining the presence of AKI at the time of deceased organ donation remains difficult. Urine samples from 182 brainstem dead multi-organ donors (all of whom donated hearts that were transplanted) were analyzed for a Luminex(™) panel of biomarkers linked with AKI. This included KIM-1, NGAL, IFN-γ, TNF-α, cystatin C, Fractalkine and vascular endothelial growth factor. Levels were correlated to early renal transplant outcomes, most specifically delayed graft function. Donor urinary KIM-1 levels were significantly higher in donors whose kidneys displayed aberrant early function (p = 0.011). Fractalkine levels showed a trend toward elevation in such donors but uncorrected this did not attain significance. No correlation occurred with the remaining biomarkers. KIM-1 appears to show promise as a marker for AKI in deceased cardiac organ donors. The availability of a lateral flow device (Renastick(™) ) for KIM-1 that also demonstrates higher urinary KIM-1 levels in donors whose kidneys show aberrant initial function (p = 0.03), makes KIM-1 a potential indicator of AKI that may merit further evaluation for its application at the donor bedside. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The impact of coronary chronic total occlusion percutaneous coronary intervention upon donor vessel fractional flow reserve and instantaneous wave-free ratio: Implications for physiology-guided PCI in patients with CTO.

PubMed

Mohdnazri, Shah R; Karamasis, Grigoris V; Al-Janabi, Firas; Cook, Christopher M; Hampton-Till, James; Zhang, Jufen; Al-Lamee, Rasha; Dungu, Jason N; Gedela, Swamy; Tang, Kare H; Kelly, Paul A; Davies, Justin E; Davies, John R; Keeble, Thomas R

2018-03-22

To investigate the immediate and short term impact of right coronary artery (RCA) chronic total coronary occlusion (CTO) percutaneous coronary intervention (PCI) upon collateral donor vessel fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR). CTO PCI influences collateral donor vessel physiology, making the indication and/or timing of donor vessel revascularization difficult to determine. In patients with RCA CTO, FFR, iFR, and collateral function index (FFR coll ) were measured in LAD and LCx pre-CTO PCI, immediately post and at 4 month follow-up. 34 patients underwent successful PCI. In the predominant donor vessel immediately post PCI, FFR, and FFR coll did not change (0.76 ± 0.12 to 0.75 ± 0.13, P = 0.267 and 0.31 ± 0.10 vs. 0.34 ± 0.11, P = 0.078), but iFR increased significantly (0.86 ± 0.10 to 0.88 ± 0.10, P = 0.012). At follow-up, there was a significant increase in predominant donor FFR and iFR (0.76 ± 0.12 to 0.79 ± 0.11, P = 0.047 and 0.86 ± 0.10 to 0.90 ± 0.07, P = 0.003), accompanied by a significant reduction in FFR coll (0.31 ± 0.10 to 0.18 ± 0.07 P < 0.0001). These changes resulted in a reclassification of the predominant donor vessel from ischemic to nonischemic in 18% (FFR) and 25% (iFR) of the cases, respectively. Successful recanalization of an RCA CTO resulted in a modest but statistically significant increase in the predominant donor vessel immediately post CTO PCI in the case of iFR and at 4-month follow-up for FFR and iFR compared to pre-PCI with a concomitant reduction in collateral function. © 2018 Wiley Periodicals, Inc.

PREOPERATIVE COMPUTED TOMOGRAPHY VOLUMETRY AND GRAFT WEIGHT ESTIMATION IN ADULT LIVING DONOR LIVER TRANSPLANTATION

PubMed Central

PINHEIRO, Rafael S.; CRUZ-JR, Ruy J.; ANDRAUS, Wellington; DUCATTI, Liliana; MARTINO, Rodrigo B.; NACIF, Lucas S.; ROCHA-SANTOS, Vinicius; ARANTES, Rubens M; LAI, Quirino; IBUKI, Felicia S.; ROCHA, Manoel S.; D´ALBUQUERQUE, Luiz A. C.

2017-01-01

ABSTRACT Background: Computed tomography volumetry (CTV) is a useful tool for predicting graft weights (GW) for living donor liver transplantation (LDLT). Few studies have examined the correlation between CTV and GW in normal liver parenchyma. Aim: To analyze the correlation between CTV and GW in an adult LDLT population and provide a systematic review of the existing mathematical models to calculate partial liver graft weight. Methods: Between January 2009 and January 2013, 28 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. All grafts were perfused with HTK solution. Estimated graft volume was estimated by CTV and these values were compared to the actual graft weight, which was measured after liver harvesting and perfusion. Results: Median actual GW was 782.5 g, averaged 791.43±136 g and ranged from 520-1185 g. Median estimated graft volume was 927.5 ml, averaged 944.86±200.74 ml and ranged from 600-1477 ml. Linear regression of estimated graft volume and actual GW was significantly linear (GW=0.82 estimated graft volume, r2=0.98, slope=0.47, standard deviation of 0.024 and p<0.0001). Spearman Linear correlation was 0.65 with 95% CI of 0.45 - 0.99 (p<0.0001). Conclusion: The one-to-one rule did not applied in patients with normal liver parenchyma. A better estimation of graft weight could be reached by multiplying estimated graft volume by 0.82. PMID:28489167

Diamagnetic susceptibility of a hydrogenic donor in a group IV-VI quantum dot-quantum well heterostructure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saravanamoorthy, S. N.; Peter, A. John, E-mail: a.john.peter@gmail.com

2016-05-23

Electronic properties of a hydrogenic donor impurity in a CdSe/Pb{sub 0.8}Cd{sub 0.2}Se/CdSe quantum dot quantum well system are investigated for various radii of core with shell materials. Confined energies are obtained taking into account the geometrical size of the system and thereby the donor binding energies are found. The diamagnetic susceptibility is estimated for a confined shallow donor in the well system. The results show that the diamagnetic susceptibility strongly depends on core and shell radii and it is more sensitive to variations of the geometrical size of the well material.

Motivational differences between whole blood and plasma donors already exist before their first donation experience.

PubMed

Veldhuizen, Ingrid; van Dongen, Anne

2013-08-01

The demand for plasma products has increased rapidly. It is therefore important to understand donating behavior by plasma donors. This study investigates whether motivational differences between whole blood and plasma donors already exist at the beginning of a donor career. New donors (n = 4861) were invited to fill out a questionnaire before their first donation (response, 61%). The questionnaire assessed variables from the Theory of Planned Behavior (intention, self-efficacy, attitude, and norms), conscientiousness, and donation anxiety. Three years later it was determined who became whole blood or plasma donor. Multivariable linear regression analyses for intention were fitted separately for whole blood and plasma donors. A logistic regression analysis was executed to estimate the effect of intention at the beginning of a donor career on becoming a plasma donor. Plasma donors had a higher intention, self-efficacy, attitude, and conscientiousness and a lower anxiety than whole blood donors. In plasma and whole blood donors, both self-efficacy and cognitive attitude were positively related to intention but with different strength (plasma, β = 0.47 and β = 0.30; whole blood, β = 0.57 and β = 0.17). Having a high level of intention increased the odds of becoming a plasma donor (odds ratio, 1.33; 95% confidence interval, 1.12-1.59). Motivational differences already exist between future whole blood and plasma donors before their first donation. Although a feeling of self-efficacy is necessary for all new donors, more favorable cognitions are important for future plasma donors. Recruitment strategies for plasma donors should focus on attracting the more self-confident donors by highlighting the usefulness of plasma donation. © 2012 American Association of Blood Banks.

Evaluation of Kidney Donors: Core Curriculum 2018.

PubMed

Sawinski, Deirdre; Locke, Jayme E

2018-05-01

Nearly 100,000 patients are waiting for a kidney transplant, yet each year only 11,000 undergo transplantation with a deceased donor kidney. Annual death rates among waitlist registrants range from 5% to 15%; many die before receiving a transplant. Not surprisingly, registrants turn to family and friends to become living kidney donors on their behalf. Living kidney donor selection practices aim to quantify lifetime risk for kidney failure based on a candidate's predonation demographic and health characteristics. It has been established that estimated lifetime risk for kidney failure varies considerably based on predonation comorbid conditions, and as such, it is of paramount importance that potential living donor candidates undergo proper medical, surgical, and psychosocial screening before donation. This installment of AJKD's Core Curriculum in Nephrology provides readers with the tools necessary for proper evaluation of living kidney donor candidates. Copyright © 2017 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Detecting specific cytotoxic T lymphocytes against SARS-coronavirus with DimerX HLA-A2:Ig fusion protein.

PubMed

Wang, Yue-Dan; Chen, Wei Feng

2004-11-01

To assess specific cytotoxic T lymphocytes (CTLs) against Severe acute respiratory syndrome (SARS)-coronavirus, a modified DimerX flow cytometry assay was performed with peripheral blood mononuclear cell (PBMC) from HLA-A2+ SARS-recovered donors at different time points post disease. CD8+DimerX-S1203+ CTLs were detected in the PBMC from these donors up to 3 months after recovery. The percentages of CD8+DimerX-S1203+ cells paralleled the numbers of interferon-gamma-positive spots in an ELISPOT assay using the same antigenic peptide. In conclusion, DimerX-based flow cytometry staining may prove to be a real-time method to screen for CTL directed at epitopes from a newly identified virus.

[Anatomy character of renal artery and treatment of living-donor renal transplantation].

PubMed

Zhang, Lei; Fei, Ji-guang; Chen, Li-zhong; Wang, Chang-xi; Deng, Su-xiong; Qiu, Jiang; Li, Jun; Chen, Guo-dong; Huang, Gang

2009-12-15

To study the anatomy characters of renal artery and the treatment of multiple arteries in living donor renal grafts. Records of 142 living donors were analyzed in our center. We analyzed the anatomic structure of renal arteries by DSA and CTA pre-transplantation. Thirty-one kidneys with multiple arteries were transplanted after reconstruction. Then clinical effects were compared between multiple-renal-arteries group (n=31) and single-renal-artery group (n=111). The incidence of multiple renal artery was 30.99%, and there was no difference between both sides (left kidney 22.54%, right kidney 22.13%). If the multiple artery occurred in left or right kidney, the incidence of the multiple artery occurred in the other side was 56.25% and 60.00%, respectively. The diameter of left main renal artery was more magnanimous (P=0.001) and the first branch was more closed to abdominal aorta (P=0.004). Operation time and warm/cool ischemia time were longer in the multiple-renal-arteries group. However, estimated blood loss, delayed graft function, acute rejection and flow rate of arcuate artery were similar in both groups, the same as serum creatinine and serum creatinine clearance rate on day 7, 1 month and 3 month post-operation. It was shown by repeated measures ANOVA that graft with multiple arteries didn't affect the tendency of renal function at early time post-operation. Comprehending the character of renal artery and accurate treatment of multiple artery anastomosis are critical for the effect of the living kidney transplantation.

Hyperfiltration-mediated injury in the remaining kidney of a transplant donor.

PubMed

Srivastava, Tarak; Hariharan, Sundaram; Alon, Uri S; McCarthy, Ellen T; Sharma, Ram; El-Meanawy, Ashraf; Savin, Virginia J; Sharma, Mukut

2018-05-29

Kidney donors face a small but definite risk of end-stage renal disease 15-30 years postdonation. The development of proteinuria, hypertension with gradual decrease in kidney function in the donor after surgical resection of 1 kidney has been attributed to hyperfiltration. Genetic variations, physiological adaptations, and co-morbidities exacerbate the hyperfiltration-induced loss of kidney function in the years following donation. A focus on glomerular hemodynamics and capillary pressure has led to the development of drugs that target the renin-angiotensin-aldosterone system (RAAS), but these agents yield mixed results in transplant recipients and donors. Recent work on glomerular biomechanical forces highlights the differential effects of tensile stress and fluid flow shear stress (FFSS) from hyperfiltration. Capillary wall stretch due to glomerular capillary pressure increases tensile stress on podocyte foot processes that cover the capillary. In parallel, increased flow of the ultrafiltrate due to single nephron glomerular filtration rate elevates FFSS on the podocyte cell body. While tensile stress invokes the RAAS, FFSS predominantly activates the COX2-PGE2-EP2 axis. Distinguishing these 2 mechanisms is critical, as current therapeutic approaches focus on the RAAS system. A better understanding of the biomechanical forces can lead to novel therapeutic agents to target FFSS through the COX2-PGE2-EP2 axis in hyperfiltration-mediated injury. We present an overview of several aspects of the risk to transplant donors and discuss the relevance of FFSS in podocyte injury, loss of glomerular barrier function leading to albuminuria and gradual loss of renal function, and potential therapeutic strategies to mitigate hyperfiltration-mediated injury to the remaining kidney.

Cancer Incidence and Mortality in a Cohort of US Blood Donors: A 20-Year Study

PubMed Central

Hirschler, Nora V.; Chinn, Artina; Busch, Michael P.; Custer, Brian

2013-01-01

Blood donors are considered one of the healthiest populations. This study describes the epidemiology of cancer in a cohort of blood donors up to 20 years after blood donation. Records from donors who participated in the Retroviral Epidemiology Donor Study (REDS, 1991–2002) at Blood Centers of the Pacific (BCP), San Francisco, were linked to the California Cancer Registry (CCR, 1991–2010). Standardized incidence ratios (SIR) were estimated using standard US 2000 population, and survival analysis used to compare all-cause mortality among donors and a random sample of nondonors with cancer from CCR. Of 55,158 eligible allogeneic blood donors followed-up for 863,902 person-years, 4,236 (7.7%) primary malignant cancers were diagnosed. SIR in donors was 1.59 (95% CI = 1.54,1.64). Donors had significantly lower mortality (adjusted HR = 0.70, 95% CI = 0.66–0.74) compared with nondonor cancer patients, except for respiratory system cancers (adjusted HR = 0.93, 95% CI = 0.82–1.05). Elevated cancer incidence among blood donors may reflect higher diagnosis rates due to health seeking behavior and cancer screening in donors. A “healthy donor effect” on mortality following cancer diagnosis was demonstrated. This population-based database and sample repository of blood donors with long-term monitoring of cancer incidence provides the opportunity for future analyses of genetic and other biomarkers of cancer. PMID:24489545

Utilization of elderly donors in living donor liver transplantation: when more is less?

PubMed

Dayangac, Murat; Taner, C Burcin; Yaprak, Onur; Demirbas, Tolga; Balci, Deniz; Duran, Cihan; Yuzer, Yildiray; Tokat, Yaman

2011-05-01

An accepted definition of donor exclusion criteria has not been established for living donor liver transplantation (LDLT). The use of elderly donors to expand the living donor pool raises ethical concerns about donor safety. The aims of this study were (1) the comparison of the postoperative outcomes of living liver donors by age (≥ 50 versus < 50 years) and (2) the evaluation of the impact of the extent of right hepatectomy on donor outcomes. The study group included 150 donors who underwent donor right hepatectomy between October 2004 and April 2009. Extended criteria surgery (ECS) was defined as right hepatectomy with middle hepatic vein (MHV) harvesting or right hepatectomy resulting in an estimated remnant liver volume (RLV) less than 35%. The primary endpoints were donor outcomes in terms of donor complications graded according to the Clavien classification. Group 1 consisted of donors who were 50 years old or older (n = 28), and group 2 consisted of donors who were less than 50 years old (n = 122). At least 1 ECS criterion was present in 74% of donors: 57% had 1 criterion, and 17% had 2 criteria. None of the donors had grade 4 complications or died. The overall and major complication rates were similar in the 2 donor age groups [28.6% and 14.3% in group 1 and 32% and 8.2% in group 2 for the overall complication rates (P = 0.8) and the major complication rates (P = 0.2), respectively]. However, there was a significant correlation between the rate of major complications and the type of surgery in donors who were 50 years old or older. In LDLT, extending the limits of surgery comes at the price of more complications in elderly donors. Right hepatectomy with MHV harvesting and any procedure causing an RLV less than 35% should be avoided in living liver donors who are 50 years old or older. Copyright © 2011 American Association for the Study of Liver Diseases.

The global financial crisis has led to a slowdown in growth of funding to improve health in many developing countries.

PubMed

Leach-Kemon, Katherine; Chou, David P; Schneider, Matthew T; Tardif, Annette; Dieleman, Joseph L; Brooks, Benjamin P C; Hanlon, Michael; Murray, Christopher J L

2012-01-01

How has funding to developing countries for health improvement changed in the wake of the global financial crisis? The question is vital for policy making, planning, and advocacy purposes in donor and recipient countries alike. We measured the total amount of financial and in-kind assistance that flowed from both public and private channels to improve health in developing countries during the period 1990-2011. The data for the years 1990-2009 reflect disbursements, while the numbers for 2010 and 2011 are preliminary estimates. Development assistance for health continued to grow in 2011, but the rate of growth was low. We estimate that assistance for health grew by 4 percent each year from 2009 to 2011, reaching a total of $27.73 billion. This growth was largely driven by the World Bank's International Bank for Reconstruction and Development and appeared to be a deliberate strategy in response to the global economic crisis. Assistance for health from bilateral agencies grew by only 4 percent, or $444.08 million, largely because the United States slowed its development assistance for health. Health funding through UN agencies stagnated, and the Global Fund to Fight AIDS, Tuberculosis, and Malaria announced that it would make no new grants for the next two years because of declines in funding. Given the international community's focus on meeting the Millennium Development Goals by 2015 and persistent economic hardship in donor countries, continued measurement of development assistance for health is essential for policy making.

Kidney transplantation from donors with rhabdomyolysis and acute renal failure.

PubMed

Chen, Chuan-Bao; Zheng, Yi-Tao; Zhou, Jian; Han, Ming; Wang, Xiao-Ping; Yuan, Xiao-Peng; Wang, Chang-Xi; He, Xiao-Shun

2017-08-01

Rhabdomyolysis in deceased donors usually causes acute renal failure (ARF), which may be considered a contraindication for kidney transplantation. From January 2012 to December 2016, 30 kidneys from 15 deceased donors with severe rhabdomyolysis and ARF were accepted for transplantation at our center. The peak serum creatinine (SCr) kinase, myoglobin, and SCr of the these donors were 15 569±8597 U/L, 37 092±42 100 μg/L, and 422±167 μmol/L, respectively. Two donors received continuous renal replacement therapy due to anuria. Six kidneys exhibited a discolored appearance (from brown to glossy black) due to myoglobin casts. The kidney transplant results from the donors with rhabdomyolysis donors were compared with those of 90 renal grafts from standard criteria donors (SCD). The estimated glomerular filtration rate at 2 years was similar between kidney transplants from donors with rhabdomyolysis and SCD (70.3±14.6 mL/min/1.73 m 2 vs 72.3±15.1 mL/min/1.73 m 2 ). We conclude that excellent graft function can be achieved from kidneys donors with ARF caused by rhabdomyolysis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Liver transplantation using elderly donors: a risk factor analysis.

PubMed

Kim, Dae Y; Moon, Jang; Island, Eddie R; Tekin, Akin; Ganz, Susan; Levi, David; Selvaggi, Gennaro; Nishida, Seigo; Tzakis, Andreas G

2011-01-01

Survival after liver transplantation is negatively impacted by use of elderly deceased donors, but excluding them would increase waiting times and waiting list mortality. We reviewed our experience with liver transplantation (LT) utilizing livers from deceased donors 65 yr of age and older to identify those factors that impact graft survival. All adult patients (≥ 18 yr old) who underwent primary LT using deceased donor livers from donors aged ≥ 65 yr between February 1995 and November 2003 were included. With multivariate analysis we found four unfavorable characteristics significantly associated with higher post-transplant graft failure rate. These characteristics are hepatitis C as an etiology of liver disease, Model for End-Stage Liver Disease score >20, serum glucose level of donor > 200 mg/dL at the time of liver recovery, and skin incision to aortic cross-clamp time > 40 minutes in the donor surgery. The five-yr estimated graft survival rates having 0, 1, 2, 3, and 4 unfavorable characteristics were 100%, 82.0%, 81.7%, 39.3%, and 25.0%, respectively (p < 0.05). Our data demonstrated good graft survival can be achieved in LT using elderly donor liver allografts with appropriate patient selection, donor blood glucose management and efficient liver recovery with minimal manipulation of the liver during donor surgery. © 2010 John Wiley & Sons A/S.

Long-term human immune system reconstitution in non-obese diabetic (NOD)-Rag (-)-γ chain (-) (NRG) mice is similar but not identical to the original stem cell donor.

PubMed

Harris, D T; Badowski, M; Balamurugan, A; Yang, O O

2013-12-01

The murine immune system is not necessarily identical to it human counterpart, which has led to the construction of humanized mice. The current study analysed whether or not a human immune system contained within the non-obese diabetic (NOD)-Rag1(null) -γ chain(null) (NRG) mouse model was an accurate representation of the original stem cell donor and if multiple mice constructed from the same donor were similar to one another. To that end, lightly irradiated NRG mice were injected intrahepatically on day 1 of life with purified cord blood-derived CD34(+) stem and progenitor cells. Multiple mice were constructed from each cord blood donor. Mice were analysed quarterly for changes in the immune system, and followed for periods up to 12 months post-transplant. Mice from the same donor were compared directly with each other as well as with the original donor. Analyses were performed for immune reconstitution, including flow cytometry, T cell receptor (TCR) and B cell receptor (BCR) spectratyping. It was observed that NRG mice could be 'humanized' long-term using cord blood stem cells, and that animals constructed from the same cord blood donor were nearly identical to one another, but quite different from the original stem cell donor immune system. © 2013 British Society for Immunology.

Techniques used for the screening of hemoglobin levels in blood donors: current insights and future directions.

PubMed

Chaudhary, Rajendra; Dubey, Anju; Sonker, Atul

2017-01-01

Blood donor hemoglobin (Hb) estimation is an important donation test that is performed prior to blood donation. It serves the dual purpose of protecting the donors' health against anemia and ensuring good quality of blood components, which has an implication on recipients' health. Diverse cutoff criteria have been defined world over depending on population characteristics; however, no testing methodology and sample requirement have been specified for Hb screening. Besides the technique, there are several physiological and methodological factors that affect accuracy and reliability of Hb estimation. These include the anatomical source of blood sample, posture of the donor, timing of sample and several other biological factors. Qualitative copper sulfate gravimetric method has been the archaic time-tested method that is still used in resource-constrained settings. Portable hemoglobinometers are modern quantitative devices that have been further modified to reagent-free cuvettes. Furthermore, noninvasive spectrophotometry was introduced, mitigating pain to blood donor and eliminating risk of infection. Notwithstanding a tremendous evolution in terms of ease of operation, accuracy, mobility, rapidity and cost, a component of inherent variability persists, which may partly be attributed to pre-analytical variables. Hence, blood centers should pay due attention to validation of test methodology, competency of operating staff and regular proficiency testing of the outputs. In this article, we have reviewed various regulatory guidelines, described the variables that affect the measurements and compared the validated technologies for Hb screening of blood donors along with enumeration of their merits and limitations.

An evaluation of the impact of donor BMI on survival and post-transplant obesity in pediatric liver transplant recipients

PubMed Central

Perito, Emily Rothbaum; Rhee, Sue; Glidden, Dave; Roberts, John Paul; Rosenthal, Philip

2012-01-01

Introduction In adult liver transplant recipients, donor BMI is associated with post-transplant obesity but not graft or patient survival. Given the U.S. obesity epidemic and already-limited supply of liver donors, clarifying whether donor BMI affects pediatric outcomes is important. Methods UNOS data on pediatric U.S. liver transplants 1990-2010 was evaluated. Data on transplants 2004-2010 (n=3788) was used for survival analysis with Kaplan-Meier and Cox proportional hazards models and for post-transplant obesity analysis with generalized estimating equations. Results For children receiving adult donor livers, donor BMI 25-35 kg/m2 was not associated with graft or patient survival in univariate or multivariate analyses. Donor BMI>35 kg/m2 increased the risk of graft loss (HR 2.54, 95%CI 1.29-5.01, p=0.007) and death (HR 3.56, 95%CI 1.64-7.72, p=0.001). For pediatric donors, donor BMI was not associated with graft loss or mortality in univariate or multivariate analysis. Donor overweight/obesity was not a risk factor for post-transplant obesity. Conclusions Overweight/obesity is common among liver transplant donors. This analysis suggests that for adult donors, BMI 25-35 should not by itself be a contraindication to liver donation. Severe obesity (BMI>35) in adult donors increased the risk of graft loss and mortality, even after adjustment for recipient, donor, and transplant risk factors. Post-transplant obesity was not associated with donor BMI in this analysis. Further research is needed to clarify the impact of donor obesity on pediatric liver transplant recipients. PMID:22467594

Effect of Replacing Race with Apolipoprotein L1 Genotype in Calculation of Kidney Donor Risk Index

PubMed Central

Julian, B. A.; Gaston, R. S.; Brown, W. M.; Reeves-Daniel, A. M.; Israni, A. K.; Schladt, D. P.; Pastan, S. O.; Mohan, S.; Freedman, B. I.; Divers, J.

2016-01-01

Renal allografts from deceased African Americans with two apolipoprotein L1 gene (APOL1) renal-risk variants fail sooner than kidneys from donors with fewer variants. Kidney Donor Risk Index (KDRI) was developed to evaluate organ offers by predicting allograft longevity and includes African American race as a risk factor. Substituting APOL1 genotype for race may refine the KDRI. For 622 deceased African American kidney donors, we applied 10-fold cross-validation approach to estimate contribution of APOL1 variants to a revised KDRI. Cross-validation was repeated 10,000 times to generate distribution of effect size associated with APOL1 genotype. Average effect size was used to derive the revised KDRI weighting. Mean current-KDRI score for all donors was 1.4930 versus mean revised-KDRI score 1.2518 for 529 donors with 0/1 variant and 1.8527 for 93 donors with 2 variants. Original and revised KDRIs had comparable survival prediction errors after transplantation, but the spread in Kidney Donor Profile Index based on presence/absence of 2 APOL1 variants was 37 percentage points. Replacing donor race with APOL1 genotype in KDRI better defines risk associated with kidneys transplanted from deceased African American donors, substantially improves KDRI score for 85-90% of kidneys offered, and enhances the link between donor quality and recipient need. PMID:27862962

The anastomosis between renal polar arteries and arteria epigastrica inferior in kidney transplantation: an option to decrease the risk of ureter necrosis?

PubMed

Wolters, H H; Schult, M; Heidenreich, S; Chariat, M; Senninger, N; Dietl, K H

2001-12-01

Ureteral necrosis after renal transplantation is often the result of impaired perfusion due to loss of donor polar arteries. A way of preserving polar arteries is their anastomosis with the A. epigastrica inferior. In three cases (aged 49-, 58-, and 63 years), 9.3 % of 33 living donors, we detected donor polar arteries on both sides, and anastomosed the polar artery to the A. epigastrica inferior with microsurgical methods. Intraoperatively, the flow was measured by flowmeter, in the postoperative course duplexsonography and MR-angiography was performed. In all three cases we noted a bluish, ischemic parenchym mass of 10-25 % of the kidney and ureter. It recovered immediately, however, after the polar artery had been reconstructed. Intraoperative measurement showed a high flow on the polar- and the main renal artery. Duplexsonography and MR-angiography documented a good flow on the A. epigastrica anastomosis. There have been no signs of ureteral problems at all. After a mean follow-up time of 26 months, the mean creatinine level is 1.46 mg/ml. Ureteral necrosis after kidney transplantation is mostly the result of a lack of perfusion of the polar arteries of the lower kidney pole. If arteriosclerotic lesions inhibit an anastomosis with the renal artery, the anastomosis with the A. epigastrica inferior seems to be a useful alternative.

Factors associated with renal function compensation after donor nephrectomy.

PubMed

Burballa, Carla; Crespo, Marta; Redondo-Pachón, Dolores; Pérez-Sáez, María José; Arias-Cabrales, Carlos; Mir, Marisa; Francés, Albert; Fumadó, Lluís; Cecchini, Lluís; Pascual, Julio

2018-05-14

Kidney transplant donors lose 50% of their renal mass after nephrectomy. The remaining kidney compensates for this loss and it is estimated that 70% of the baseline renal function prior to donation is recovered. Factors associated with post-donation renal compensation are not well understood. Retrospective study of 66 consecutive kidney donors (mean age 48.8 years, 74.2% women). We analysed the potential factors associated with the compensatory mechanisms of the remaining kidney by comparing donors according to their renal compensation rate (RCR) (Group A, infra-compensation [<70%]; Group B, normal compensation [>70%]). We compared Group A (n=38) and group B (n=28). Predictors for RCR>70% were higher baseline creatinine (A vs B: 0.73±0.14 vs 0.82±0.11; P=.03) and a lower baseline glomerular filtration rate (GFR), estimated both by MDRD-4 (A vs B: 97.7±18.8 vs 78.6±9.6ml/min; P<.001) and CKD-EPI (A vs B: 101.7±15 vs. 88.3±11.7ml/min; P≤.001). Age, gender, smoking, hypertension and GFR measured by Tc-DTPA did not show any correlation with the RCR. The multivariate analysis confirmed baseline estimated glomerular filtration rate (eGFR) to be a predictor of compensation: the higher the baseline eGFR, the lower the likelihood of >70% compensation (MDRD-4, OR=0.94 [95% CI 0.8-0.9], P=.01). The compensation rate decreased by 0.4% (P<.001) and 0.3% (P=.006) for every ml/min increase in baseline eGFR estimated by MDRD-4 and CKD-EPI, respectively. One year after living donor nephrectomy, the remaining kidney partially compensates baseline renal function. In our experience, baseline eGFR is inversely proportional to the one-year renal compensation rate. Copyright © 2018 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

Preoperative TRAM free flap volume estimation for breast reconstruction in lean patients.

PubMed

Minn, Kyung Won; Hong, Ki Yong; Lee, Sang Woo

2010-04-01

To obtain pleasing symmetry in breast reconstruction with transverse rectus abdominis myocutaneous (TRAM) free flap, a large amount of abdominal flap is elevated and remnant tissue is trimmed in most cases. However, elevation of abundant abdominal flap can cause excessive tension in donor site closure and increase the possibility of hypertrophic scarring especially in lean patients. The TRAM flap was divided into 4 zones in routine manner; the depth and dimension of the 4 zones were obtained using ultrasound and AutoCAD (Autodesk Inc., San Rafael, CA), respectively. The acquired numbers were then multiplied to obtain an estimate of volume of each zone and the each zone volume was added. To confirm the relation between the estimated volume and the actual volume, authors compared intraoperative actual TRAM flap volumes with preoperative estimated volumes in 30 consecutive TRAM free flap breast reconstructions. The estimated volumes and the actual elevated volumes of flap were found to be correlated by regression analysis (r = 0.9258, P < 0.01). According to this result, we could confirm the reliability of the preoperative volume estimation using our method. Afterward, the authors applied this method to 7 lean patients by estimation and revision of the design and obtained symmetric results with minimal donor site morbidity. Preoperative estimation of TRAM flap volume with ultrasound and AutoCAD (Autodesk Inc.) allow the authors to attain the precise volume desired for elevation. This method provides advantages in terms of minimal flap trimming, easier closure of donor sites, reduced scar widening and symmetry, especially in lean patients.

11 years of tracking aid to reproductive, maternal, newborn, and child health: estimates and analysis for 2003-13 from the Countdown to 2015.

PubMed

Grollman, Christopher; Arregoces, Leonardo; Martínez-Álvarez, Melisa; Pitt, Catherine; Mills, Anne; Borghi, Josephine

2017-01-01

Tracking aid flows helps to hold donors accountable and to compare the allocation of resources in relation to health need. With the use of data reported by donors in 2015, we provided estimates of official development assistance and grants from the Bill & Melinda Gates Foundation (collectively termed ODA+) to reproductive, maternal, newborn, and child health for 2013 and complete trends in reproductive, maternal, newborn, and child health support for the period 2003-13. We coded and analysed financial disbursements to reproductive, maternal, newborn, and child health to all recipient countries from all donors reporting to the creditor reporting system database for the year 2013. We also revisited disbursement records for the years 2003-08 and coded disbursements relating to reproductive and sexual health activities resulting in the Countdown dataset for 2003-13. We matched this dataset to the 2015 creditor reporting system dataset and coded any unmatched creditor reporting system records. We analysed trends in ODA+ to reproductive, maternal, newborn, and child health for the period 2003-13, trends in donor contributions, disbursements to recipient countries, and targeting to need. Total ODA+ to reproductive, maternal, newborn, and child health reached nearly US$14 billion in 2013, of which 48% supported child health ($6·8 billion), 34% supported reproductive and sexual health ($4·7 billion), and 18% maternal and newborn health ($2·5 billion). ODA+ to reproductive, maternal, newborn, and child health increased by 225% in real terms over the period 2003-13. Child health received the most substantial increase in funding since 2003 (286%), followed by reproductive and sexual health (194%), and maternal and newborn health (164%). In 2013, bilateral donors disbursed 59% of all ODA+ to reproductive, maternal, newborn, and child health, followed by global health initiatives (23%), and multilateral agencies (13%). Targeting of ODA+ to reproductive, maternal, newborn, and child health to countries with the greatest health need seems to have improved over time. The increase in reproductive, maternal, newborn, and child health funding over the period 2003-13 is encouraging. Further increases in funding will be needed to accelerate maternal mortality reduction while keeping a high level of investment in sexual and reproductive health and in child health. Subgrant OPP1058954 from the US Fund for UNICEF under their Countdown to 2015 for Maternal, Newborn and Child Survival Grant from the Bill & Melinda Gates Foundation. Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.

Comparison of computer tomographic volumetry versus nuclear split renal function to determine residual renal function after living kidney donation.

PubMed

Patankar, Khalil; Low, Ronny Su-Tong; Blakeway, Darryn; Ferrari, Paolo

2014-07-01

Living-donor kidney transplantation is an established practice. Traditionally a combination of renal scintigram and computed tomography (CT) is used to select the kidney that is to be harvested in each donor. To evaluate the ability of split renal volume (SRV) calculated from volumetric examination of CT images compared to nuclear split renal function (nSRF) derived from gamma camera scintigram to predict donor residual single kidney function after donor nephrectomy. This pilot study comprised a retrospective analysis of CT images and renal scintigrams from 12 subsequent live kidney donors who had at least 12 months post-donation renal function follow-up. nSRF derived from the renal scintigram, expressed as the right kidney's function in percent of the total, was 50.2 ± 3.3 (range, 44.1-54.0%) and SRV estimated following analysis of CT imaging was 49.0 ± 2.9 (range, 46.4-52.3%). Although the correlation between nSRF and SRV was moderate (R = 0.46), there was 92% agreement on the dominant kidney if a difference of <2% in nSRF versus SRV was considered. Post-donation glomerular filtration rate (GFR) by CKD-EPI formula was 92 ± 10 mL/min/1.73m2 at 1 year and the correlation between estimated GFR (eGFR) at 1 year and extrapolated single kidney eGFR adjusted by nSRF (R(2 )= 0.69, P = 0.0007) or SRV (R(2 )= 0.74, P = 0.0003) was similar. Calculation of SRV from pre-donation CT examination is a valid method to estimate nSRF with good concordance with nSRF determined by renal scintigram and could replace the latter in the assessment of potential kidney donors. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Whole exome sequencing to estimate alloreactivity potential between donors and recipients in stem cell transplantation

PubMed Central

Sampson, Juliana K.; Sheth, Nihar U.; Koparde, Vishal N.; Scalora, Allison F.; Serrano, Myrna G.; Lee, Vladimir; Roberts, Catherine H.; Jameson-Lee, Max; Ferreira-Gonzalez, Andrea; Manjili, Masoud H.; Buck, Gregory A.; Neale, Michael C.; Toor, Amir A.

2016-01-01

Summary Whole exome sequencing (WES) was performed on stem cell transplant donor-recipient (D-R) pairs to determine the extent of potential antigenic variation at a molecular level. In a small cohort of D-R pairs, a high frequency of sequence variation was observed between the donor and recipient exomes independent of human leucocyte antigen (HLA) matching. Nonsynonymous, nonconservative single nucleotide polymorphisms were approximately twice as frequent in HLA-matched unrelated, compared with related D-R pairs. When mapped to individual chromosomes, these polymorphic nucleotides were uniformly distributed across the entire exome. In conclusion, WES reveals extensive nucleotide sequence variation in the exomes of HLA-matched donors and recipients. PMID:24749631

Cost-effectiveness of alternative changes to a national blood collection service.

PubMed

Willis, S; De Corte, K; Cairns, J A; Zia Sadique, M; Hawkins, N; Pennington, M; Cho, G; Roberts, D J; Miflin, G; Grieve, R

2018-05-16

To evaluate the cost-effectiveness of changing opening times, introducing a donor health report and reducing the minimum inter-donation interval for donors attending static centres. Evidence is required about the effect of changes to the blood collection service on costs and the frequency of donation. This study estimated the effect of changes to the blood collection service in England on the annual number of whole-blood donations by current donors. We used donors' responses to a stated preference survey, donor registry data on donation frequency and deferral rates from the INTERVAL trial. Costs measured were those anticipated to differ between strategies. We reported the cost per additional unit of blood collected for each strategy versus current practice. Strategies with a cost per additional unit of whole blood less than £30 (an estimate of the current cost of collection) were judged likely to be cost-effective. In static donor centres, extending opening times to evenings and weekends provided an additional unit of whole blood at a cost of £23 and £29, respectively. Introducing a health report cost £130 per additional unit of blood collected. Although the strategy of reducing the minimum inter-donation interval had the lowest cost per additional unit of blood collected (£10), this increased the rate of deferrals due to low haemoglobin (Hb). The introduction of a donor health report is unlikely to provide a sufficient increase in donation frequency to justify the additional costs. A more cost-effective change is to extend opening hours for blood collection at static centres. © 2018 The Authors. Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.

Donor funding for family planning: levels and trends between 2003 and 2013.

PubMed

Grollman, Christopher; Cavallaro, Francesca L; Duclos, Diane; Bakare, Victoria; Martínez Álvarez, Melisa; Borghi, Josephine

2018-05-01

The International Conference on Population and Development in 1994 set targets for donor funding to support family planning programmes, and recent initiatives such as FP2020 have renewed focus on the need for adequate funding to rights-based family planning. Disbursements supporting family planning disaggregated by donor, recipient country and year are not available for recent years. We estimate international donor funding for family planning in 2003-13, the period covering the introduction of reproductive health targets to the Millennium Development Goals and up to the beginning of FP2020, and compare funding to unmet need for family planning in recipient countries. We used the dataset of donor disbursements to support reproductive, maternal, newborn and child health developed by the Countdown to 2015 based on the Organization for Economic Cooperation and Development Creditor Reporting System. We assessed levels and trends in disbursements supporting family planning in the period 2003-13 and compared this to unmet need for family planning. Between 2003 and 2013, disbursements supporting family planning rose from under $400 m prior to 2008 to $886 m in 2013. More than two thirds of disbursements came from the USA. There was substantial year-on-year variation in disbursement value to some recipient countries. Disbursements have become more concentrated among recipient countries with higher national levels of unmet need for family planning. Annual disbursements of donor funding supporting family planning are far short of projected and estimated levels necessary to address unmet need for family planning. The reimposition of the US Global Gag Rule will precipitate an even greater shortfall if other donors and recipient countries do not find substantial alternative sources of funding.

Donor funding for family planning: levels and trends between 2003 and 2013

PubMed Central

Grollman, Christopher; Cavallaro, Francesca L; Duclos, Diane; Bakare, Victoria; Martínez Álvarez, Melisa; Borghi, Josephine

2018-01-01

Abstract The International Conference on Population and Development in 1994 set targets for donor funding to support family planning programmes, and recent initiatives such as FP2020 have renewed focus on the need for adequate funding to rights-based family planning. Disbursements supporting family planning disaggregated by donor, recipient country and year are not available for recent years. We estimate international donor funding for family planning in 2003–13, the period covering the introduction of reproductive health targets to the Millennium Development Goals and up to the beginning of FP2020, and compare funding to unmet need for family planning in recipient countries. We used the dataset of donor disbursements to support reproductive, maternal, newborn and child health developed by the Countdown to 2015 based on the Organization for Economic Cooperation and Development Creditor Reporting System. We assessed levels and trends in disbursements supporting family planning in the period 2003–13 and compared this to unmet need for family planning. Between 2003 and 2013, disbursements supporting family planning rose from under $400 m prior to 2008 to $886 m in 2013. More than two thirds of disbursements came from the USA. There was substantial year-on-year variation in disbursement value to some recipient countries. Disbursements have become more concentrated among recipient countries with higher national levels of unmet need for family planning. Annual disbursements of donor funding supporting family planning are far short of projected and estimated levels necessary to address unmet need for family planning. The reimposition of the US Global Gag Rule will precipitate an even greater shortfall if other donors and recipient countries do not find substantial alternative sources of funding. PMID:29534176

Quantification of hepatic macrosteatosis in living, related liver donors using T1-independent, T2*-corrected chemical shift MRI.

PubMed

Joe, Eugene; Lee, Jeong Min; Kim, Kyung Won; Lee, Kyung Bun; Kim, Soo Jin; Baek, Jee Hyun; Shin, Cheong Il; Suh, Kyung Suk; Yi, Nam Joon; Han, Joon Koo; Choi, Byung Ihn

2012-11-01

To evaluate the diagnostic implications of the iterative decomposition of water and fat using echo-asymmetry and the least-squares estimation (IDEAL) technique to detect hepatic steatosis (HS) in potential liver donors using histopathology as the reference standard. Forty-nine potential liver donors (32 male, 17 female; mean age, 31.7 years) were included. All patients were imaged using the in- and out-of-phase (IOP) gradient-echo (GRE) and IDEAL techniques on a 1.5 T MR scanner. To estimate the hepatic fat fraction (FF), two reviewers performed regions-of-interest measurement in 15 areas of the liver seen on the IOP images and on the IDEAL-FF images. The magnetic resonance imaging (MRI) and pathology values of macrosteatosis were correlated using the Pearson correlation coefficient. We analyzed the diagnostic performance of IOP imaging and IDEAL for detecting HS. The results of the hepatic-FF estimated on IDEAL were well correlated with the histologic degree of macrosteatosis (γ = 0.902, P < 0.001). IDEAL showed 100% sensitivity and 91% specificity for detecting HS, and IOP imaging showed 87.5% sensitivity and 97% specificity, respectively. IDEAL is a useful tool for the preoperative diagnosis of HS in potential living liver donors; it can also help to avoid unnecessary biopsies in these patients. Copyright © 2012 Wiley Periodicals, Inc.

Co-infusion of haplo-identical CD19-chimeric antigen receptor T cells and stem cells achieved full donor engraftment in refractory acute lymphoblastic leukemia.

PubMed

Cai, Bo; Guo, Mei; Wang, Yao; Zhang, Yajing; Yang, Jun; Guo, Yelei; Dai, Hanren; Yu, Changlin; Sun, Qiyun; Qiao, Jianhui; Hu, Kaixun; Zuo, Hongli; Dong, Zheng; Zhang, Zechuan; Feng, Mingxing; Li, Bingxia; Sun, Yujing; Liu, Tieqiang; Liu, Zhiqing; Wang, Yi; Huang, Yajing; Yao, Bo; Han, Weidong; Ai, Huisheng

2016-11-25

Elderly patients with relapsed and refractory acute lymphoblastic leukemia (ALL) have poor prognosis. Autologous CD19 chimeric antigen receptor-modified T (CAR-T) cells have potentials to cure patients with B cell ALL; however, safety and efficacy of allogeneic CD19 CAR-T cells are still undetermined. We treated a 71-year-old female with relapsed and refractory ALL who received co-infusion of haplo-identical donor-derived CD19-directed CAR-T cells and mobilized peripheral blood stem cells (PBSC) following induction chemotherapy. Undetectable minimal residual disease by flow cytometry was achieved, and full donor cell engraftment was established. The transient release of cytokines and mild fever were detected. Significantly elevated serum lactate dehydrogenase, alanine transaminase, bilirubin and glutamic-oxalacetic transaminase were observed from days 14 to 18, all of which were reversible after immunosuppressive therapy. Our preliminary results suggest that co-infusion of haplo-identical donor-derived CAR-T cells and mobilized PBSCs may induce full donor engraftment in relapsed and refractory ALL including elderly patients, but complications related to donor cell infusions should still be cautioned. Allogeneic CART-19 for Elderly Relapsed/Refractory CD19+ ALL. NCT02799550.

Adverse Reactions in Allogeneic Blood Donors: A Tertiary Care Experience from a Developing Country.

PubMed

Sultan, Sadia; Baig, Mohammad Amjad; Irfan, Syed Mohammed; Ahmed, Syed Ijlal; Hasan, Syeda Faiza

2016-03-01

Fragmented blood transfusion services along with an unmotivated blood donation culture often leads to blood shortage. Donor retention is crucial to meet the increasing blood demand, and adverse donor reactions have a negative impact on donor return. The aim of this study was to estimate adverse donor reactions and identify any demographic association.  . We conducted a prospective study between January 2011 and December 2013. A total of 41,759 healthy donors were enrolled. Professionally trained donor attendants drew blood and all donors were observed during and following donation for possible adverse events for 20 minutes. Blood donors were asked to report if they suffered from any delayed adverse consequences.  . Out of 41,759 blood donors, 537 (1.3%) experienced adverse reactions. The incidence was one in every 78 donations. The mean age of donors who experienced adverse events was 26.0±6.8 years, and all were male. Out of 537 donors, 429 (80%) developed vasovagal reaction (VVR), 133 (25%) had nausea, 63 (12%) fainted, 35 (6%) developed hyperventilation, 9 (2%) had delayed syncope, and 9 (2%) developed hematoma. Arterial prick, nerve injury, cardiac arrest, and seizures were not observed. Donors aged less than < 30 years and weighing < 70 kg were significantly associated with VVR, hyperventilation, and nausea (p < 0.005). Undergraduates and Urdu speaking donors also had a significant association with fainting and nausea, respectively (p < 0.05).  . The prevalence of adverse events was low at our tertiary center. A VVR was the predominant adverse reaction and was associated with age and weight. Our study highlights the importance of these parameters in the donation process. A well-trained and experienced phlebotomist and pre-evaluation counseling of blood donors could further minimize the adverse reactions.

Down scaled Kjeldahl digestion and flow injection conductometric system for determination of protein content in some traditional northern Thai foods.

PubMed

Yanu, Pattama; Jakmunee, Jaroon

2017-09-01

A flow injection conductometric (FIC) system for determination of total Kjeldahl nitrogen (TKN) was developed for estimating total protein content in food. A small scale Kjeldahl digestion was performed with a short digestion time of only 20min. The digested solution was injected into the FIC system, and TKN was converted to ammonia gas in an alkaline donor stream of the system. The gas diffused through a membrane and dissolved into an acceptor stream causing an increase in conductivity as detected by a detector and recorded as a peak. Under the optimum condition, a linear calibration graph in the range of 4.00-100.00mgL -1 was obtained with LOD of 0.05mgL -1 . A good precision (0.04% RSD, n=11, 30.00mgNL -1 ) and high sample throughput of 72h -1 was achieved. The method was applied for determination of protein in some traditional northern Thai foods, revealing that they are good sources of proteins. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Blood Group A Genotype Determines the Level of Expression of the Blood Group A on Platelets But Not the Anti-B Isotiter

PubMed Central

Lehner, Barbara; Eichelberger, Beate; Jungbauer, Christof; Panzer, Simon

2015-01-01

Summary Background The extent of expression of the blood group A on platelets is controversial. Further, the relation between platelets' blood group A expression and the titers of isoagglutinins has not been thoroughly investigated, so far. Methods We evaluated the relation between the genotype with platelets' blood group A and H expression estimated by flow cytometry and the titers of isoagglutinins. Results The A expression varied between genotypes and within genotypes. However, the expression in A1 was stronger than in all other genotypes (p < 0.0001). An overlap of expression levels was apparent between homozygous A1A1 and heterozygous A1 individuals. Still, The A1A1 genotype is associated with a particularly high antigen expression (p = 0.009). Platelets' A expression in A2 versus blood group O donors was also significant (p = 0.007), but there was again an overlap of expression. The secretor status had only little influence on the expression (p = 0.18). Also, isoagglutinin titers were not associated with genotypes. Conclusion: To distinguish between A1 and A2 donors may reduce incompatible platelet transfusions and therefore be favorable on platelet transfusion increment. Clinical data are needed to support this notion. PMID:26733767

Intensity correlation-based calibration of FRET.

PubMed

Bene, László; Ungvári, Tamás; Fedor, Roland; Sasi Szabó, László; Damjanovich, László

2013-11-05

Dual-laser flow cytometric resonance energy transfer (FCET) is a statistically efficient and accurate way of determining proximity relationships for molecules of cells even under living conditions. In the framework of this algorithm, absolute fluorescence resonance energy transfer (FRET) efficiency is determined by the simultaneous measurement of donor-quenching and sensitized emission. A crucial point is the determination of the scaling factor α responsible for balancing the different sensitivities of the donor and acceptor signal channels. The determination of α is not simple, requiring preparation of special samples that are generally different from a double-labeled FRET sample, or by the use of sophisticated statistical estimation (least-squares) procedures. We present an alternative, free-from-spectral-constants approach for the determination of α and the absolute FRET efficiency, by an extension of the presented framework of the FCET algorithm with an analysis of the second moments (variances and covariances) of the detected intensity distributions. A quadratic equation for α is formulated with the intensity fluctuations, which is proved sufficiently robust to give accurate α-values on a cell-by-cell basis in a wide system of conditions using the same double-labeled sample from which the FRET efficiency itself is determined. This seemingly new approach is illustrated by FRET measurements between epitopes of the MHCI receptor on the cell surface of two cell lines, FT and LS174T. The figures show that whereas the common way of α determination fails at large dye-per-protein labeling ratios of mAbs, this presented-as-new approach has sufficient ability to give accurate results. Although introduced in a flow cytometer, the new approach can also be straightforwardly used with fluorescence microscopes. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Estimation of Right-Lobe Graft Weight From Computed Tomographic Volumetry for Living Donor Liver Transplantation.

PubMed

Yang, X; Chu, C W; Yang, J D; Yang, K H; Yu, H C; Cho, B H; You, H

2017-03-01

The objective of the study was to establish a right-lobe graft weight (GW) estimation formula for living donor liver transplantation (LDLT) from right-lobe graft volume without veins (GV w/o_veins ), including portal vein and hepatic vein measured by computed tomographic (CT) volumetry, and to compare its estimation accuracy with those of existing formulas. Right-lobe GW estimation formulas established with the use of graft volume with veins (GV w_veins ) sacrifice accuracy because GW measured intra-operatively excludes the weight of blood in the veins. Right-lobe GW estimation formulas have been established with the use of right-lobe GV w/o_veins , but a more accurate formula must be developed. The present study developed right-lobe GW estimation formulas based on GV w/o_veins as well as GV w_veins , using 40 cases of Korean donors: GW = 29.1 + 0.943 × GV w/o_veins (adjusted R 2  = 0.94) and GW = 74.7 + 0.773 × GV w_veins (adjusted R 2  = 0.87). The proposed GW estimation formulas were compared with existing GV w_veins - and GV w/o_veins -based models, using 43 cases additionally obtained from two medical centers for cross-validation. The GV w/o_veins -based formula developed in the present study was most preferred (absolute error = 21.5 ± 16.5 g and percentage of absolute error = 3.0 ± 2.3%). The GV w/o_veins -based formula is preferred to the GV w_veins -based formula in GW estimation. Accurate CT volumetry and alignment between planned and actual surgical cutting lines are crucial in the establishment of a better GW estimation formula. Copyright © 2016 Elsevier Inc. All rights reserved.

Blood donor show behaviour after an invitation to donate: The influence of collection site factors.

PubMed

Merz, E-M; Zijlstra, B J H; de Kort, W L A M

2017-10-01

Show behaviour after invitation to donate varies considerably across donors. More insight into this variation is important for blood banks in achieving stable stocks. This study examined individual factors determining intended show behaviour. Most importantly, however, this study is the first study to account for variation in donor behaviour across different collection sites. We applied a multilevel approach to data from Donor InSight, including 11 889 donors from 257 fixed and mobile collection sites in the Netherlands. The aim of the multilevel models was to account for variance at two levels, that is donors and collection sites. We estimated the likelihood of showing after invitation based on individual predictors, including demographics, donation history and attitude. At the collection site level, we included satisfaction with the blood bank aggregated from individual responses by donors who donate at this site, opening hours and collection site type, that is fixed/mobile. Most importantly, show behaviour varied considerably across collection sites and depended on characteristics of these sites. Moreover, women, older and more experienced donors had higher odds of showing after invitation than men, younger and less experienced donors. Donors higher on warm glow, self-efficacy and donor identity more likely showed after an invitation. Higher aggregate satisfaction and donating at fixed collection sites increased the odds of show. In addition to individual factors, collection site characteristics are important in explaining variation in donor show behaviour, thus presenting clues for blood bank policies and interventions to improve donor show. © 2017 International Society of Blood Transfusion.

The introduction of anti-HTLV testing of blood donations and the risk of transfusion-transmitted HTLV, UK: 2002-2006.

PubMed

Davison, K L; Dow, B; Barbara, J A; Hewitt, P E; Eglin, R

2009-02-01

The objectives of the study were to describe the introduction of testing blood donations for antibodies to human T-cell lymphotropic virus (anti-HTLV) and to determine the risk of HTLV potentially infectious donations entering the UK blood supply. The rationale for testing was based on (i) evidence of transmission through transfusion in the UK, (ii) the serious nature of HTLV I-associated morbidity and (iii) evidence of infection in UK blood donors. From mid-2002, all blood donations made at UK blood centres were tested in pooled samples using Abbott-Murex HTLV I/II GE 80/81 enzyme immunoassay (EIA). Surveillance data were used to calculate the incidence and prevalence of anti-HTLV and derive estimates of risk. Between August 2002 and December 2006, 106 donations were confirmed positive for anti-HTLV (95 anti-HTLV I and 11 anti-HTLV II). Prevalence was 10-fold higher among donations from new donors than repeat (4.0 and 0.42 per 100 000 donations), and only one repeat donor had evidence of seroconversion. The risk of an HTLV I potentially infectious donation entering the UK blood supply was estimated at 0.11 per million donations (95% confidence interval 0.06 to 0.18). The current very low observed incidence and prevalence among blood donors reflect the very low estimated risk of an HTLV I-positive donation entering the UK blood supply. A change in either the epidemiology of HTLV in UK blood donors or the length of the window period of the test should prompt further review of the risk and a reassessment of anti-HTLV testing in the UK.

Donor-specific hypo-responsiveness occurs in simultaneous liver-kidney transplant recipients after the first year.

PubMed

Taner, Timucin; Gustafson, Michael P; Hansen, Michael J; Park, Walter D; Bornschlegl, Svetlana; Dietz, Allan B; Stegall, Mark D

2018-06-01

Kidney allografts of patients who undergo simultaneous liver-kidney transplantation incur less immune-mediated injury, and retain better function compared to other kidney allografts. To characterize the host alloimmune responses in 28 of these patients, we measured the donor-specific alloresponsiveness and phenotypes of peripheral blood cells after the first year. These values were then compared to those of 61 similarly immunosuppressed recipients of a solitary kidney or 31 recipients of liver allografts. Four multicolor, non-overlapping flow cytometry protocols were used to assess the immunophenotypes. Mixed cell cultures with donor or third party cells were used to measure cell proliferation and interferon gamma production. Despite a significant overlap, simultaneous liver-kidney transplant recipients had a lower overall frequency of circulating CD8 + , activated CD4 + and effector memory T cells, compared to solitary kidney transplant recipients. Simultaneous liver-kidney transplant recipient T cells had a significantly lower proliferative response to the donor cells compared to solitary kidney recipients (11.9 vs. 42.9%), although their response to third party cells was unaltered. The frequency of interferon gamma producing alloreactive T cells in simultaneous liver-kidney transplant recipients was significantly lower than that of solitary kidney transplant recipients. Flow cytometric analysis of the mixed cultures demonstrated that both alloreactive CD4 + and CD8 + compartments of the simultaneous liver-kidney transplant recipient circulating blood cells were smaller. Thus, the phenotypic and functional characteristics of the circulating blood cells of the simultaneous liver-kidney transplant recipients resembled those of solitary liver transplant recipients, and appear to be associated with donor-specific hypo-alloresponsiveness. Copyright © 2018 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Can value for money be improved by changing the sequence of our donor work-up in the living kidney donor programme?

PubMed

Larsen, Jesper; Sørensen, Søren Schwartz; Feldt-Rasmussen, Bo

2009-08-01

The aim of the study was to identify procedures of maximum importance for acceptance or rejection of kidney donation from a living donor as well as making the process more cost-effective. We identified all potential living related donors who were examined during the period between January 2002 and December 2006 at our department. The cost in euro (euro) for the programme was estimated using the Danish diagnosis-related group-system (DRG). The donor work-up programme was described. One hundred and thirty-three potential donors were identified; 66 male- and 67 female subjects, median age of 52 years (range 22-69). Sixty-four participants were rejected as donors. Abdominal CT-scan with angiography and urography ruled out 22 of the above 64 potential organ donors; thus, 48% of the volunteers for living kidney donation were unsuited for donation. Abdominal CT-scan with angiography and urography was the procedure identifying most subjects who were unsuited for kidney donation. A rearrangement of the present donor work-up programme could potentially reduce the costs from euro6911 to euro5292 per donor--saving 23% of the costs. By changing the sequence of examinations, it might be possible to cut down on time spent and number of tests needed for approving or rejecting subjects for living kidney donation.

Promoting Organ Donor Registries Through Public Education: What Is the Cost of Securing Organ Donors?

PubMed

Razdan, Manik; Smith, Kenneth J; Bryce, Cindy L; Degenholtz, Howard B

2016-06-01

Transplant medicine's impact on America's public health is seriously limited by acute shortage of transplantable organs. Consequently, the United Sates has witnessed considerable investment in the promotion of organ donor registries. Although there is no evidence to support that donor registry promotion alleviates organ shortage, this belief continues to drive investments into registry promotion. In this study, return on investment in donor registry promotion was examined using cost-outcomes analysis. Cost of promoting the donor registry was estimated in US dollars whereas the outcome was measured as the number of individuals who join the registry (registrants) and their value in terms of organ donors. The study was conducted from the perspective of a regional Organ Procurement Organization (OPO). Costs were directly obtained from the OPO. The number of new registrants was obtained from the OPO and the departments of motor vehicles that maintain the donor registry. The value of registrants in terms of organ donors was computed based on a registrant's age-dependent risk of dying and age-dependent probability of becoming an organ donor. Six thousand seven hundred eight individuals joined the organ donor registry (95% confidence interval [95% CI], 5429-7956) at a cost of $455 per registrant (95% CI, US $383-US $562). These individuals result in 4.2 present-day donors (95% CI, 2.5-6.6) at a cost of US $726 000 (95% CI, US $462000-US $1.2 million). Because the cost per registrant and cost per donor is less than society's willingness to pay, donor registry promotion offers positive return on investment. Investment in registry promotion should at the minimum be maintained at current levels.

Towards a global system of vigilance and surveillance in unrelated donors of haematopoietic progenitor cells for transplantation.

PubMed

Shaw, B E; Chapman, J; Fechter, M; Foeken, L; Greinix, H; Hwang, W; Phillips-Johnson, L; Korhonen, M; Lindberg, B; Navarro, W H; Szer, J

2013-11-01

Safety of living donors is critical to the success of blood, tissue and organ transplantation. Structured and robust vigilance and surveillance systems exist as part of some national entities, but historically no global systems are in place to ensure conformity, harmonisation and the recognition of rare adverse events (AEs). The World Health Assembly has recently resolved to require AE/reaction (AE/R) reporting both nationally and globally. The World Marrow Donor Association (WMDA) is an international organisation promoting the safety of unrelated donors and progenitor cell products for use in haematopoietic progenitor cell (HPC) transplantation. To address this issue, we established a system for collecting, collating, analysing, distributing and reacting to serious adverse events and reactions (SAE/R) in unrelated HPC donors. The WMDA successfully instituted this reporting system with 203 SAE/R reported in 2011. The committee generated two rapid reports, reacting to specific SAE/R, resulting in practice changing policies. The system has a robust governance structure, formal feedback to the WMDA membership and transparent information flows to other agencies, specialist physicians and transplant programs and the general public.

The effect of variation in donor platelet function on transfusion outcome: a semirandomized controlled trial.

PubMed

Kelly, Anne M; Garner, Stephen F; Foukaneli, Theodora; Godec, Thomas R; Herbert, Nina; Kahan, Brennan C; Deary, Alison; Bakrania, Lekha; Llewelyn, Charlotte; Ouwehand, Willem H; Williamson, Lorna M; Cardigan, Rebecca A

2017-07-13

The effect of variation in platelet function in platelet donors on patient outcome following platelet transfusion is unknown. This trial assessed the hypothesis that platelets collected from donors with highly responsive platelets to agonists in vitro assessed by flow cytometry (high-responder donors) are cleared more quickly from the circulation than those from low-responder donors, resulting in lower platelet count increments following transfusion. This parallel group, semirandomized double-blinded trial was conducted in a single center in the United Kingdom. Eligible patients were those 16 or older with thrombocytopenia secondary to bone marrow failure, requiring prophylactic platelet transfusion. Patients were randomly assigned to receive a platelet donation from a high- or low-responder donor when both were available, or when only 1 type of platelet was available, patients received that. Participants, investigators, and those assessing outcomes were masked to group assignment. The primary end point was the platelet count increment 10 to 90 minutes following transfusion. Analysis was by intention to treat. Fifty-one patients were assigned to receive platelets from low-responder donors, and 49 from high-responder donors (47 of which were randomized and 53 nonrandomized). There was no significant difference in platelet count increment 10 to 90 minutes following transfusion in patients receiving platelets from high-responder (mean, 21.0 × 10 9 /L; 95% confidence interval [CI], 4.9-37.2) or low-responder (mean, 23.3 × 10 9 /L; 95% CI, 7.8-38.9) donors (mean difference, 2.3; 95% CI, -1.1 to 5.7; P = .18). These results support the current policy of not selecting platelet donors on the basis of platelet function for prophylactic platelet transfusion. © 2017 by The American Society of Hematology.

High-resolution HLA haplotype frequencies of stem cell donors in Germany with foreign parentage: how can they be used to improve unrelated donor searches?

PubMed

Pingel, Julia; Solloch, Ute V; Hofmann, Jan A; Lange, Vinzenz; Ehninger, Gerhard; Schmidt, Alexander H

2013-03-01

In hematopoietic stem cell transplantation, human leukocyte antigens (HLA), usually HLA loci A, B, C, DRB1 and DQB1, are required to check histocompatibility between a potential donor and the recipient suffering from a malignant or non-malignant blood disease. As databases of potential unrelated donors are very heterogeneous with respect to typing resolution and number of typed loci, donor registries make use of haplotype frequency-based algorithms to provide matching probabilities for each potentially matching recipient/donor pair. However, it is well known that HLA allele and haplotype frequencies differ significantly between populations. We estimated high-resolution HLA-A, -B, -C, -DRB1 haplotype and allele frequencies of donors within DKMS German Bone Marrow Donor Center with parentage from 17 different countries: Turkey, Poland, Italy, Russian Federation, Croatia, Greece, Austria, Kazakhstan, France, The Netherlands, Republic of China, Romania, Portugal, USA, Spain, United Kingdom and Bosnia and Herzegovina. 5-locus haplotypes including HLA-DQB1 are presented for Turkey, Poland, Italy and Russian Federation. We calculated linkage disequilibria for each sample. Genetic distances between included countries could be shown to reflect geography. We further demonstrate how genetic differences between populations are reflected in matching probabilities of recipient/donor pairs and how they influence the search for unrelated donors as well as strategic donor center typings. Copyright © 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Trypanosoma cruzi in a low- to moderate-risk blood donor population: seroprevalence and possible congenital transmission.

PubMed

Leiby, D A; Fucci, M H; Stumpf, R J

1999-03-01

Several recent studies documented the seroprevalence of Trypanosoma cruzi in blood donors at high risk for infection, but little information is available regarding donors with lower levels of risk. Thus, the present study was designed to measure the seroprevalence of T. cruzi in a donor population with a low to moderate risk for infection. During a 10-month period, donations from all allogeneic blood donors in the American Red Cross Southwest Region were tested for T. cruzi antibodies by enzyme immunoassay, and results were confirmed by radioimmunoprecipitation. Confirmed-seropositive donors were counseled and lookback investigations were initiated for those who were repeat donors. A total of 100,089 donations were tested: 150 were repeatably reactive, and 3 (0.003%) were confirmed as positive for T. cruziantibodies. All three seropositive donors were from the Waco, TX, area, where the estimated seroprevalence rate was 1 in 7700. Two of these three donors reported no risk factors; both were born in the United States and had not traveled to an endemic area. Both had extensive familial histories of cardiac disease and complications. Blood donors seropositive for T. cruzi are present in populations with low to moderate risk, albeit at lower rates. The presence of seropositive blood donors without the usual identifiable risk factors argues against the use of a geographic screening question and also suggests that other routes of transmission, including the congenital route, should be considered in efforts to increase blood safety.

The risk of HIV, HBV, HCV and HTLV infection among musculoskeletal tissue donors in Australia.

PubMed

Yao, F; Seed, C; Farrugia, A; Morgan, D; Cordner, S; Wood, D; Zheng, M H

2007-12-01

In Australia, there are no current national estimates of the risks of transmission of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) or human T-lymphotrophic virus (HTLV) by musculoskeletal tissue transplantation. We determined the prevalence rates of antibodies against HIV (anti-HIV), HCV (anti-HCV) and HTLV (anti-HTLV) and Hepatitis B surface antigen (HBsAg) for 12,415 musculoskeletal tissue donors from three major bone tissue banks across Australia for the period 1993-2004. The prevalence (per 100,000 persons) was 64.44 for anti-HIV, 407.13 for HBsAg, 534.63 for anti-HCV and 121.88 for anti-HTLV. The estimated probability of viremia at the time of donation was 1 in 128,000, 1 in 189,000, 1 in 55,000 and 1 in 118,000, respectively. With the addition of nucleic acid amplification testing (NAT), the probability of donor viremia would be reduced to 1 in 315,000 for HIV, 1 in 385,000 for HBV and 1 in 500,000 for HCV. The prevalence of HIV, HBV, HCV and HTLV although low, are higher among musculoskeletal tissue donors than among first-time blood donors. The risks associated with musculoskeletal donation will be reduced with NAT, though further cost analysis is required prior to its implementation.

Whole exome sequencing to estimate alloreactivity potential between donors and recipients in stem cell transplantation.

PubMed

Sampson, Juliana K; Sheth, Nihar U; Koparde, Vishal N; Scalora, Allison F; Serrano, Myrna G; Lee, Vladimir; Roberts, Catherine H; Jameson-Lee, Max; Ferreira-Gonzalez, Andrea; Manjili, Masoud H; Buck, Gregory A; Neale, Michael C; Toor, Amir A

2014-08-01

Whole exome sequencing (WES) was performed on stem cell transplant donor-recipient (D-R) pairs to determine the extent of potential antigenic variation at a molecular level. In a small cohort of D-R pairs, a high frequency of sequence variation was observed between the donor and recipient exomes independent of human leucocyte antigen (HLA) matching. Nonsynonymous, nonconservative single nucleotide polymorphisms were approximately twice as frequent in HLA-matched unrelated, compared with related D-R pairs. When mapped to individual chromosomes, these polymorphic nucleotides were uniformly distributed across the entire exome. In conclusion, WES reveals extensive nucleotide sequence variation in the exomes of HLA-matched donors and recipients. © 2014 John Wiley & Sons Ltd.

Renal donors with prostate cancer, no longer a reason to decline.

PubMed

Dholakia, S; Johns, R; Muirhead, L; Papalois, V; Crane, J

2016-01-01

To fully assess the true risk of prostate cancer transmission in during renal transplantation. A full review of all existing literature relevant to the topic. There has not been a single documented case of transmission of prostate cancer during renal transplant. Prostate cancer in deceased organ donors has an incidence estimated between 3% and 18.5% and over 100 transplants have been performed using organs from donor with proven prostate cancer without issue. Transmission of prostate cancer through kidney transplantation seems very unlikely. The risks of remaining on the waiting list are outweighed by a transmission risk and the potential benefit makes the case to have clear guidelines about donor prostate malignancy when accepting potential organs. Copyright © 2015. Published by Elsevier Inc.

Corneal Tissue From Dry Eye Donors Leads to Enhanced Graft Rejection.

PubMed

Inomata, Takenori; Hua, Jing; Nakao, Takeshi; Shiang, Tina; Chiang, Homer; Amouzegar, Afsaneh; Dana, Reza

2018-01-01

To assess the effect of dry eye disease (DED) in graft donors on dendritic cell (DC) maturation, host T-cell sensitization, and corneal allograft rejection. Corneas of control (healthy donor) and DED mice (C57BL/6) were transplanted onto fully allogeneic naive BALB/c recipients (n = 10 mice/group). Long-term allograft survival was evaluated for 8 weeks. Corneas and draining lymph nodes (dLNs) were harvested at posttransplantation day 14 (n = 5 mice/group). The frequencies of MHCII CD11c DCs in the donor corneas and host dLNs and the frequencies of interferon (IFN)-γ and IL-17 CD4 T cells and Foxp3 expression by Tregs in host dLNs were investigated using flow cytometry. The enzyme-linked immunospot assay was used to assess host T-cell allosensitization through direct and indirect pathways (n = 3/group). Recipients of DED donor corneas showed significantly reduced graft survival (10%) compared with control mice (50% survival, P = 0.022), and had significantly increased frequencies of mature DCs in the grafted cornea (DED donor 44.0% ± 0.36% vs. healthy donor 35.4 ± 0.5%; P < 0.0001) and host dLNs (DED donor 25.1% ± 0.66% vs. healthy donor 13.7% ± 1.6%; P = 0.005). Frequencies of IFN-γ and IL-17 T cells were increased in the dLNs of recipients of DED corneas, whereas the expression (mean fluorescence intensity) of Foxp3 in Tregs was decreased significantly in these mice (DED donor 6004 ± 193 vs. healthy donor 6806 ± 81; P = 0.0002). Enzyme-linked immunospot analysis showed that the direct pathway of allosensitization was significantly amplified in recipients of grafts with DED (P = 0.0146). Our results indicate that DED in the donor is a significant risk factor for subsequent corneal allograft rejection.

Preoperative estimation of the liver graft weight in adult right lobe living donor liver transplantation using maximal portal vein diameters.

PubMed

Wang, Frank; Pan, Kuang-Tse; Chu, Sung-Yu; Chan, Kun-Ming; Chou, Hong-Shiue; Wu, Ting-Jung; Lee, Wei-Chen

2011-04-01

An accurate preoperative estimate of the graft weight is vital to avoid small-for-size syndrome in the recipient and ensure donor safety after adult living donor liver transplantation (LDLT). Here we describe a simple method for estimating the graft volume (GV) that uses the maximal right portal vein diameter (RPVD) and the maximal left portal vein diameter (LPVD). Between June 2004 and December 2009, 175 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. The GV was determined with 3 estimation methods: (1) the radiological graft volume (RGV) estimated by computed tomography (CT) volumetry; (2) the computed tomography-calculated graft volume (CGV-CT), which was obtained by the multiplication of the standard liver volume (SLV) by the RGV percentage with respect to the total liver volume derived from CT; and (3) the portal vein diameter ratio-calculated graft volume (CGV-PVDR), which was obtained by the multiplication of the SLV by the portal vein diameter ratio [PVDR; ie, PVDR = RPVD(2) /(RPVD(2) + LPVD(2) )]. These values were compared to the actual graft weight (AGW), which was measured intraoperatively. The mean AGW was 633.63 ± 107.51 g, whereas the mean RGV, CGV-CT, and CGV-PVDR values were 747.83 ± 138.59, 698.21 ± 94.81, and 685.20 ± 90.88 cm(3) , respectively. All 3 estimation methods tended to overestimate the AGW (P < 0.001). The actual graft-to-recipient body weight ratio (GRWR) was 1.00% ± 0.19%, and the GRWRs calculated on the basis of the RGV, CGV-CT, and CGV-PVDR values were 1.19% ± 0.25%, 1.11% ± 0.22%, and 1.09% ± 0.21%, respectively. Overall, the CGV-PVDR values better correlated with the AGW and GRWR values according to Lin's concordance correlation coefficient and the Landis and Kock benchmark. In conclusion, the PVDR method is a simple estimation method that accurately predicts GVs and GRWRs in adult LDLT. Copyright © 2011 American Association for the Study of Liver Diseases.

Central-cell corrections and shallow donor states in strong magnetic fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jayam, Sr. Gerardin; Navaneethakrishnan, K.

2001-06-01

Ionization energies and the central-cell corrections have been calculated for a few shallow donors in Si, GaP, and GaAs. We have assumed a short range potential with two parameters for the strength and the range for each donor, representing the central-cell effects. These parameters are fixed using the experimentally available ionization energies for each donor in a semiconductor. In the presence of a magnetic field the donor ionization energies are estimated using a variational procedure. Our results show that the ionization energies and the central-cell corrections increase with magnetic field. Our results are compared for GaAs with the recent workmore » by Heron et al. [R. J. Heron, R. A. Lewis, P. E. Simmonds, R. P. Starret, A. V. Skougarevsky, R. G. Clark, and C. R. Stanley, J. Appl. Phys. 85, 893 (1999)]. {copyright} 2001 American Institute of Physics.« less

Transport of spin qubits with donor chains under realistic experimental conditions

NASA Astrophysics Data System (ADS)

Mohiyaddin, Fahd A.; Kalra, Rachpon; Laucht, Arne; Rahman, Rajib; Klimeck, Gerhard; Morello, Andrea

2016-07-01

The ability to transport quantum information across some distance can facilitate the design and operation of a quantum processor. One-dimensional spin chains provide a compact platform to realize scalable spin transport for a solid-state quantum computer. Here, we model odd-sized donor chains in silicon under a range of experimental nonidealities, including variability of donor position within the chain. We show that the tolerance against donor placement inaccuracies is greatly improved by operating the spin chain in a mode where the electrons are confined at the Si-SiO2 interface. We then estimate the required time scales and exchange couplings, and the level of noise that can be tolerated to achieve high-fidelity transport. We also propose a protocol to calibrate and initialize the chain, thereby providing a complete guideline for realizing a functional donor chain and utilizing it for spin transport.

Transport of spin qubits with donor chains under realistic experimental conditions

DOE PAGES

Mohiyaddin, Fahd A.; Kalra, Rachpon; Laucht, Arne; ...

2016-07-25

The ability to transport quantum information across some distance can facilitate the design and operation of a quantum processor. One-dimensional spin chains provide a compact platform to realize scalable spin transport for a solid-state quantum computer. Here, we model odd-sized donor chains in silicon under a range of experimental nonidealities, including variability of donor position within the chain. We show that the tolerance against donor placement inaccuracies is greatly improved by operating the spin chain in a mode where the electrons are confined at the Si-SiO 2 interface. We then estimate the required time scales and exchange couplings, and themore » level of noise that can be tolerated to achieve high-fidelity transport. As a result, we also propose a protocol to calibrate and initialize the chain, thereby providing a complete guideline for realizing a functional donor chain and utilizing it for spin transport.« less

Post-donation telephonic interview of blood donors providing an insight into delayed adverse reactions: First attempt in India.

PubMed

Tiwari, Aseem K; Aggarwal, Geet; Dara, Ravi C; Arora, Dinesh; Srivastava, Khushboo; Raina, Vimarsh

2017-04-01

Blood donor experiences both immediate adverse reactions (IAR) and delayed adverse reactions (DAR). With limited published data available on the incidence of DAR, a study was conducted to estimate incidence and profile of DAR through telephonic interview. Study was conducted over a 45-day period for consecutive volunteer whole blood donations at tertiary care hospital. Donors were divided into first-time, repeat and regular and were monitored for IAR. They were given written copy of post-donation advice. Donors were contacted telephonically three weeks post-donation and enquired about general wellbeing and specific DAR in accordance with a standard n international (International Society of Blood Transfusion) standard format. Donors participated in the study of which 1.6% donors experienced an IAR. Much larger number reported DAR (10.3% vs.1.6% p<0.0001). Further, DAR was presented as a variegated profile with bruise, painful arms and fatigue being the commonest. DARs were more common in females than males (25% vs. 10.3%, p<0.02). Localized DAR like bruise and painful arms were more common in younger donors (age <50 years) whereas systemic DAR like fatigue was common in older donors (>50 years). First time (12.3%) and repeat donors (13.5%) had similar frequency of DAR but were lower among regular donors (6.7%). DARs are more common than IAR and are of different profile. Post-donation interview has provided an insight into donor experiences and can be used as a valuable tool in donor hemovigilance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Limited occurrence of denitrification in four shallow aquifers in agricultural areas of the United States

USGS Publications Warehouse

Green, C.T.; Puckett, L.J.; Böhlke, J.K.; Bekins, B.A.; Phillips, S.P.; Kauffman, L.J.; Denver, J.M.; Johnson, H.M.

2008-01-01

The ability of natural attenuation to mitigate agricultural nitrate contamination in recharging aquifers was investigated in four important agricultural settings in the United States. The study used laboratory analyses, field measurements, and flow and transport modeling for monitoring well transects (0.5 to 2.5 km in length) in the San Joaquin watershed, California, the Elkhorn watershed, Nebraska, the Yakima watershed, Washington, and the Chester watershed, Maryland. Ground water analyses included major ion chemistry, dissolved gases, nitrogen and oxygen stable isotopes, and estimates of recharge date. Sediment analyses included potential electron donors and stable nitrogen and carbon isotopes. Within each site and among aquifer-based medians, dissolved oxygen decreases with ground water age, and excess N2 from denitrification increases with age. Stable isotopes and excess N2 imply minimal denitrifying activity at the Maryland and Washington sites, partial denitrification at the California site, and total denitrification across portions of the Nebraska site. At all sites, recharging electron donor concentrations are not sufficient to account for the losses of dissolved oxygen and nitrate, implying that relict, solid phase electron donors drive redox reactions. Zero-order rates of denitrification range from 0 to 0.14 μmol N L−1d−1, comparable to observations of other studies using the same methods. Many values reported in the literature are, however, orders of magnitude higher, which is attributed to a combination of method limitations and bias for selection of sites with rapid denitrification. In the shallow aquifers below these agricultural fields, denitrification is limited in extent and will require residence times of decades or longer to mitigate modern nitrate contamination.

Prevalence of celiac disease among blood donors in São Paulo: the most populated city in Brazil.

PubMed

Alencar, Marília Lage; Ortiz-Agostinho, Carmen Lucia; Nishitokukado, Lêda; Damião, Adérson O M C; Abrantes-Lemos, Clarice P; Leite, André Zonetti de Arruda; Brito, Thales de; Chamone, Dalton de Alencar Fischer; Silva, Maria Elizabeth Rossi da; Giannella-Neto, Daniel; Sipahi, Aytan Miranda

2012-09-01

Celiac disease is a permanent enteropathy caused by the ingestion of gluten, which leads to an immunemediated inflammation of the small intestine mucosa. The prevalence of celiac disease varies among different nations and ethnic backgrounds, and its diversity is determined by genetic and environmental factors. São Paulo city is one of the largest cities in the world, with a vast population and an important history of internal migratory flow from other Brazilian regions, as well as immigration from other, primarily European, countries, resulting in significant miscegenation. The aim of the present study was to estimate the prevalence of adults with undiagnosed celiac disease among blood donors of São Paulo by collecting information on the ancestry of the population studied. The prevalence of celiac disease was assessed by screening for positive IgA transglutaminase and IgA endomysium antibodies in 4,000 donors (volunteers) in the Fundação Pró-Sangue Blood Center of São Paulo, São Paulo, Brazil. The antibody-positive subjects were asked to undergo a small bowel biopsy. Of the 4,000 subjects, twenty-four had positive tests, although both antibody tests were not always concordant. For example, ten subjects were positive for IgA tissue transglutaminase only. In twenty-one positive patients, duodenal biopsies were performed, and the diagnosis of celiac disease was confirmed in fourteen patients (Marsh criteria modified by Oberhuber). In this group, 67% claimed to have European ancestry, mainly from Italy, Portugal and Spain. The prevalence of celiac disease is at least 1:286 among supposedly healthy blood bank volunteers in São Paulo, Brazil.

77 FR 14801 - Request for Information (RFI) on Design of a Pilot Operational Study To Assess Alternative Blood...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-13

... Incidence Surveillance Group. Estimated HIV Incidence in the United States, 2006-2009. PLoS One. 2011;6(8... donors who meet all other donor eligibility criteria, and have negative pre-donation test results, would...' disease), and a serologic test for syphilis. A pre-donation testing strategy would focus on the prevalence...

Risk-adjusted outcome measurement in pediatric allogeneic stem cell transplantation.

PubMed

Matthes-Martin, Susanne; Pötschger, Ulrike; Bergmann, Kirsten; Frommlet, Florian; Brannath, Werner; Bauer, Peter; Klingebiel, Thomas

2008-03-01

The purpose of the study was to define a risk score for 1-year treatment-related mortality (TRM) in children undergoing allogeneic stem cell transplantation as a basis for risk-adjusted outcome assessment. We analyzed 1364 consecutive stem cell transplants performed in 24 German and Austrian centers between 1998 and 2003. Five well-established risk factors were tested by multivariate logistic regression for predictive power: patient age, disease status, donor other than matched sibling donor, T cell depletion (TCD), and preceding stem cell transplantation. The risk score was defined by rounding the parameter estimates of the significant risk factors to the nearest integer. Crossvalidation was performed on the basis of 5 randomly extracted equal-sized parts from the database. Additionally, the score was validated for different disease entities and for single centers. Multivariate analysis revealed a significant correlation of TRM with 3 risk factors: age >10 years, advanced disease, and alternative donor. The parameter estimates were 0.76 for age, 0.73 for disease status, and 0.97 for donor type. Rounding the estimates resulted in a score with 1 point for each risk factor. One-year TRM (overall survival [OS]) were 5% (89%) with a score of 0, 18% (74%) with 1, 28% (54%) with 2, and 53% (27%) with 3 points. Crossvalidation showed stable results with a good correlation between predicted and observed mortality but moderate discrimination. The score seems to be a simple instrument to estimate the expected mortality for each risk group and for each center. Measuring TRM risk-adjusted and the comparison between expected and observed mortality may be an additional tool for outcome assessment in pediatric stem cell transplantation.

Long-term medical outcomes among Aboriginal living kidney donors.

PubMed

Storsley, Leroy J; Young, Ann; Rush, David N; Nickerson, Peter W; Ho, Julie; Suon, Vuthana; Karpinski, Martin

2010-08-27

It is unknown whether favorable long-term data on the safety of living kidney donation can be extrapolated to populations at higher risk of chronic kidney disease. Indigenous people (i.e., Aboriginals) have a high prevalence of risk factors for chronic kidney disease and Aboriginal living donor outcomes need to be defined. We performed a retrospective cohort study of all 38 Aboriginal donors donating at our center since 1970 and 76 randomly selected white donor controls to determine the long-term rates of hypertension, diabetes, and renal function postdonation. Follow-up was obtained for 91% of both Aboriginal and white donors (mean follow-up approximately 14 years). Hypertension has been diagnosed more frequently among Aboriginal donors (Ab 42% vs. white 19%, P=0.02). Notably, all 11 Aboriginal donors more than 20 years postdonation have developed hypertension. Diabetes has also been diagnosed more frequently among Aboriginal donors (Ab 19% vs. white 2%, P=0.005), including 5 of 11 (45%) more than 20 years postdonation. Follow-up estimated glomerular filtration rate was higher in Aboriginal donors (Ab 77+/-17 vs. white 67+/-13 mL/min/1.73 m, P=0.002) but not significantly different in adjusted analyses. One Aboriginal donor developed end-stage renal disease 14 years postdonation. Aboriginal living kidney donors at our center have high rates of hypertension and diabetes on long-term follow-up, although renal function is preserved to date. This profile is similar to that of the general unselected Aboriginal population despite detailed medical evaluation before donation. These findings have important implications for donor counseling and may have implications for other high-risk donor populations.

High Center Volume Does Not Mitigate Risk Associated with Using High Donor Risk Organs in Liver Transplantation.

PubMed

Beal, Eliza W; Black, Sylvester M; Mumtaz, Khalid; Hayes, Don; El-Hinnawi, Ashraf; Washburn, Kenneth; Tumin, Dmitry

2017-09-01

High-risk donor allografts increase access to liver transplant, but potentially reduce patient and graft survival. It is unclear whether the risk associated with using marginal donor livers is mitigated by increasing center experience. The United Network for Organ Sharing registry was queried for adult first-time liver transplant recipients between 2/2002 and 12/2015. High donor risk was defined as donor risk index >1.9, and 1-year patient and graft survival were compared according to donor risk index in small and large centers. Multivariable Cox regression estimated the hazard ratio (HR) associated with using high-risk donor organs, according to a continuous measure of annual center volume. The analysis included 51,770 patients. In 67 small and 67 large centers, high donor risk index predicted increased mortality (p = 0.001). In multivariable analysis, high-donor risk index allografts predicted greater mortality hazard at centers performing 20 liver transplants per year (HR 1.35; 95% CI 1.22, 1.49; p < 0.001) and, similarly, at centers performing 70 per year (HR 1.35; 95% CI 1.26, 1.43; p < 0.001). The interaction between high donor risk index and center volume was not statistically significant (p = 0.747), confirming that the risk associated with using marginal donor livers was comparable between smaller and larger centers. Results were consistent when examining graft loss. At both small and large centers, high-risk donor allografts were associated with reduced patient and graft survival after liver transplant. Specific strategies to mitigate the risk of liver transplant involving high-risk donors are needed, in addition to accumulation of center expertise.

Organ Donor Recovery Performed at an Organ Procurement Organization-Based Facility Is an Effective Way to Minimize Organ Recovery Costs and Increase Organ Yield.

PubMed

Doyle, Majella; Subramanian, Vijay; Vachharajani, Neeta; Collins, Kelly; Wellen, Jason R; Stahlschmidt, Emily; Brockmeier, Diane; Coleman, Jason; Kappel, Dean; Chapman, William C

2016-04-01

A new era in organ donation with national redistricting is being proposed. With these proposals, costs of organ acquisition are estimated to more than double. Traditionally, organ recoveries occur in the donor hospital setting, incurring premium hospital expenses. The aim of the study was to determine organ recovery costs and organ yield for donor recoveries performed at an organ procurement organization (OPO) facility. In 2001, we established an OPO facility and in 2008 began transferring the donor expeditiously when brain death was declared. The OPO donor and hospital costs on a per donor basis were calculated. Donation after cardiac death donors cannot be transferred and were included in the hospital cost analysis. From January 2009 to December 2014, nine hundred and sixty-three donors originating in our OPO had organs recovered and transplanted. Seven hundred and sixty-six (79.5%) donors were transferred to the OPO facility 8.6 hours (range 0.6 to 23.6 hours) after declaration of brain death. Donor recovery cost was 51% less when donors were transferred to the OPO facility ($16,153 OPO recovery vs $33,161 hospital recovery; p < 0.0001). Organ yield was 27.5% better (3.43 organs) from OPO-recovered donors vs an organ yield of 2.69 from hospital-recovered donors (p < 0.0001). Standard criteria donor organ yield from our OPO was 6% higher than the national average (3.92 vs 3.7 nationally; p = 0.012) and expanded criteria donor organ yield was 18% higher (2.2 vs 1.87 nationally; p = 0.03). An OPO facility for donor organ recovery increases efficiency and organ yield, reduces costs, and minimizes organ acquisition charge. As we face new considerations with broader sharing, increased efficiencies, cost. and organ use should be considered. Copyright © 2016 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Toward Current Standards of Donor Right Hepatectomy for Adult-to-Adult Live Donor Liver Transplantation Through the Experience of 200 Cases

PubMed Central

Chan, See Ching; Fan, Sheung Tat; Lo, Chung Mau; Liu, Chi Leung; Wong, John

2007-01-01

Objective: To define the current standards of donor right hepatectomy, including the middle hepatic vein for adult-to-adult live donor liver transplantation. Summary Background Data: Donor morbidity and mortality are inevitable given the ultra-major nature of the donor operation. Results from a matured center could define the true impact of this donor procedure most accurately. Patients and Methods: From May 9, 1996 to April 13, 2005, 200 consecutive donors underwent donor right hepatectomy at the University of Hong Kong Medical Center. All right liver grafts except one included the middle hepatic vein. Donor characteristics, operation time, blood loss, hospital stay, laboratory results, and complications graded by Clavien's classification divided into four eras (each consecutive 50 cases) were compared. Results: Donor characteristics of the four eras were generally comparable. Operative outcomes improved progressively through the four eras. From era 1 to era 4, operation time decreased from 598 minutes (range, 378–932 minutes) to 391 minutes (range, 304–635 minutes). Blood loss also decreased from 500 mL (200–1600 mL) of era 1 to 251 mL (range, 95–595 mL) of era 4. Overall complication rate was 20.5% (41 of 200). Complications rates from eras 1 to 4 were 34%, 16%, 16%, and 16%, respectively. The most common complications were of grade I (24 of 41, 58.5%). A late donor death occurred in era 4 from the development of a duodenocaval fistula 10 weeks postoperation, giving a donor mortality of 0.5% (1 of 200). Conclusions: This study validated the estimated morbidity and mortality of donor right hepatectomy of 20% and 0.5%, respectively. The data provide reference for counseling potential donors and setting the standards of donor right hepatectomy in the current era. PMID:17197973

Modeling In Situ Bioremediation of Perchlorate-Contaminated Groundwater

NASA Astrophysics Data System (ADS)

Goltz, M. N.; Secody, R. E.; Huang, J.; Hatzinger, P. B.

2007-12-01

Perchlorate-contaminated groundwater is a significant national problem. An innovative technology was recently developed which uses a pair of dual-screened treatment wells to mix an electron donor into perchlorate- contaminated groundwater in order to effect in situ bioremediation of the perchlorate by indigenous perchlorate reducing bacteria (PRB) without the need to extract the contaminated water from the subsurface. The two treatment wells work in tandem to establish a groundwater recirculation zone in the subsurface. Electron donor is added and mixed into perchlorate-contaminated groundwater flowing through each well. The donor serves to stimulate biodegradation of the perchlorate by PRB in bioactive zones that form adjacent to the injection screens of the treatment wells. In this study, a model that simulates operation of the technology was calibrated using concentration data obtained from a field-scale technology evaluation project at a perchlorate-contaminated site. The model simulates transport of perchlorate, the electron donor (citrate, for this study), and competing electron acceptors (oxygen and nitrate) in the groundwater flow field induced by operation of the treatment well pair. A genetic algorithm was used to derive a set of best-fit model parameters to describe the perchlorate reduction kinetics in this field-scale evaluation project. The calibrated parameter values were then used to predict technology performance. The model qualitatively predicted the salient characteristics of the observed data. It appears the model may be a useful tool for designing and operating this technology at other perchlorate-contaminated sites.

The correlation between preoperative volumetry and real graft weight: comparison of two volumetry programs.

PubMed

Mussin, Nadiar; Sumo, Marco; Lee, Kwang-Woong; Choi, YoungRok; Choi, Jin Yong; Ahn, Sung-Woo; Yoon, Kyung Chul; Kim, Hyo-Sin; Hong, Suk Kyun; Yi, Nam-Joon; Suh, Kyung-Suk

2017-04-01

Liver volumetry is a vital component in living donor liver transplantation to determine an adequate graft volume that meets the metabolic demands of the recipient and at the same time ensures donor safety. Most institutions use preoperative contrast-enhanced CT image-based software programs to estimate graft volume. The objective of this study was to evaluate the accuracy of 2 liver volumetry programs (Rapidia vs . Dr. Liver) in preoperative right liver graft estimation compared with real graft weight. Data from 215 consecutive right lobe living donors between October 2013 and August 2015 were retrospectively reviewed. One hundred seven patients were enrolled in Rapidia group and 108 patients were included in the Dr. Liver group. Estimated graft volumes generated by both software programs were compared with real graft weight measured during surgery, and further classified into minimal difference (≤15%) and big difference (>15%). Correlation coefficients and degree of difference were determined. Linear regressions were calculated and results depicted as scatterplots. Minimal difference was observed in 69.4% of cases from Dr. Liver group and big difference was seen in 44.9% of cases from Rapidia group (P = 0.035). Linear regression analysis showed positive correlation in both groups (P < 0.01). However, the correlation coefficient was better for the Dr. Liver group (R 2 = 0.719), than for the Rapidia group (R 2 = 0.688). Dr. Liver can accurately predict right liver graft size better and faster than Rapidia, and can facilitate preoperative planning in living donor liver transplantation.

Gamma-H2AX-based dose estimation for whole and partial body radiation exposure.

PubMed

Horn, Simon; Barnard, Stephen; Rothkamm, Kai

2011-01-01

Most human exposures to ionising radiation are partial body exposures. However, to date only limited tools are available for rapid and accurate estimation of the dose distribution and the extent of the body spared from the exposure. These parameters are of great importance for emergency triage and clinical management of exposed individuals. Here, measurements of γ-H2AX immunofluorescence by microscopy and flow cytometry were compared as rapid biodosimetric tools for whole and partial body exposures. Ex vivo uniformly X-irradiated blood lymphocytes from one donor were used to generate a universal biexponential calibration function for γ-H2AX foci/intensity yields per unit dose for time points up to 96 hours post exposure. Foci--but not intensity--levels remained significantly above background for 96 hours for doses of 0.5 Gy or more. Foci-based dose estimates for ex vivo X-irradiated blood samples from 13 volunteers were in excellent agreement with the actual dose delivered to the targeted samples. Flow cytometric dose estimates for X-irradiated blood samples from 8 volunteers were in excellent agreement with the actual dose delivered at 1 hour post exposure but less so at 24 hours post exposure. In partial body exposures, simulated by mixing ex vivo irradiated and unirradiated lymphocytes, foci/intensity distributions were significantly over-dispersed compared to uniformly irradiated lymphocytes. For both methods and in all cases the estimated fraction of irradiated lymphocytes and dose to that fraction, calculated using the zero contaminated Poisson test and γ-H2AX calibration function, were in good agreement with the actual mixing ratios and doses delivered to the samples. In conclusion, γ-H2AX analysis of irradiated lymphocytes enables rapid and accurate assessment of whole body doses while dispersion analysis of foci or intensity distributions helps determine partial body doses and the irradiated fraction size in cases of partial body exposures.

Comparison of Two Devices for Intraoperative Portal Venous Flow Measurement in Living-Donor Liver Transplantation: Transit Time Ultrasound and Conventional Doppler Ultrasound.

PubMed

Wang, H-K; Chen, C-Y; Lin, N-C; Liu, C-S; Loong, C-C; Lin, Y-H; Lai, Y-C; Chiou, H-J

2018-05-01

Intraoperative portal venous flow measurement provides surgeons with instant guidance for portal flow modulation during living-donor liver transplantation (LDLT). In this study, we compared the agreement of portal flow measurement obtained by 2 devices: transit time ultrasound (TTU) and conventional Doppler ultrasound (CDU). Fifty-four recipients of LDLT underwent intraoperative measurement of portal flow after completion of vascular anastomosis of the implanted partial liver graft. Both TTU and CDU were used concurrently. Agreement of TTU and CDU was assessed by intraclass correlation coefficient using a model of 2-way random effects, absolute agreement, and single measurement. A Bland-Altman plot was applied to assess the variability between the 2 devices. The mean, median, and range of portal venous flow was 1456, 1418, and 117 to 2776 mL/min according to TTU; and 1564, 1566, and 119 to 3216 mL/min according to CDU. The intraclass correlation coefficient of portal venous flow between TTU and CDU was 0.68 (95% confidence interval, 0.51-0.80). The Bland-Altman plots revealed an average variation of 4.8% between TTU and CDU but with a rather wide 95% confidence interval of variation ranging from -57.7% to 67.4%. Intraoperative TTU and CDU showed moderate agreement in portal flow measurement. However, a relatively wide range of variation exists between TTU and CDU, indicating that data obtained from the 2 devices may not be interchangeable. Copyright © 2018 Elsevier Inc. All rights reserved.

Small-for-size syndrome in live donor liver transplantation-Pathways of injury and therapeutic strategies.

PubMed

Goldaracena, Nicolas; Echeverri, Juan; Selzner, Markus

2017-02-01

Due to the severe organ shortage and the increasing gap between the supply and demand for donor grafts, live donor liver transplantation (LDLT) has become an accepted and alternative technique for the expansion of the donor pool. However, donor safety and good recipient outcomes must be balanced regarding risk stratification and decision-making within this patient population. Small-for-size syndrome (SFSS) is one of the complications encountered after LDLT, thus increasing the burden of optimizing donor graft selection and effective treatments during its occurrence. A graft-to-recipient weight ratio (GRWR) <0.8 predisposes the graft to SFSS. However, other factors may induce this complication even without a graft-to-patient size mismatch. Several strategies to prevent this complication include portal vein flow and liver outflow modulation, as well as pharmacological treatment. Also, as an entity with a multifactorial etiology, outcomes vary between right-lobe, left-lobe, and posterior-lobe donation among series encountered in the literature. In this review, we analyze the pathophysiology and classification of this complication, the state-of-the-art on management of SFSS, and the outcomes regarding the best treatment strategy on this patient population. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Validation of systems biology derived molecular markers of renal donor organ status associated with long term allograft function.

PubMed

Perco, Paul; Heinzel, Andreas; Leierer, Johannes; Schneeberger, Stefan; Bösmüller, Claudia; Oberhuber, Rupert; Wagner, Silvia; Engler, Franziska; Mayer, Gert

2018-05-03

Donor organ quality affects long term outcome after renal transplantation. A variety of prognostic molecular markers is available, yet their validity often remains undetermined. A network-based molecular model reflecting donor kidney status based on transcriptomics data and molecular features reported in scientific literature to be associated with chronic allograft nephropathy was created. Significantly enriched biological processes were identified and representative markers were selected. An independent kidney pre-implantation transcriptomics dataset of 76 organs was used to predict estimated glomerular filtration rate (eGFR) values twelve months after transplantation using available clinical data and marker expression values. The best-performing regression model solely based on the clinical parameters donor age, donor gender, and recipient gender explained 17% of variance in post-transplant eGFR values. The five molecular markers EGF, CD2BP2, RALBP1, SF3B1, and DDX19B representing key molecular processes of the constructed renal donor organ status molecular model in addition to the clinical parameters significantly improved model performance (p-value = 0.0007) explaining around 33% of the variability of eGFR values twelve months after transplantation. Collectively, molecular markers reflecting donor organ status significantly add to prediction of post-transplant renal function when added to the clinical parameters donor age and gender.

Does size matter? Kidney transplant donor size determines kidney function among living donors

PubMed Central

Narasimhamurthy, Meenakshi; Smith, Lachlan M.; Machan, Jason T.; Reinert, Steven E.; Gohh, Reginald Y.; Dworkin, Lance D.; Merhi, Basma; Patel, Nikunjkumar; Beland, Michael D.

2017-01-01

Background Kidney donor outcomes are gaining attention, particularly as donor eligibility criteria continue to expand. Kidney size, a useful predictor of recipient kidney function, also likely correlates with donor outcomes. Although donor evaluation includes donor kidney size measurements, the association between kidney size and outcomes are poorly defined. Methods We examined the relationship between kidney size (body surface area-adjusted total volume, cortical volume and length) and renal outcomes (post-operative recovery and longer-term kidney function) among 85 kidney donors using general linear models and time-to-chronic kidney disease data. Results Donors with the largest adjusted cortical volume were more likely to achieve an estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 over a median 24-month follow-up than those with smaller cortical volumes (P <0.001), had a shorter duration of renal recovery (1.3–2.2 versus 32.5 days) and started with a higher eGFR at pre-donation (107–110 versus 91 mL/min/1.73 m2) and immediately post-nephrectomy (∼63 versus 50–51 mL/min/1.73 m2). Similar findings were seen with adjusted total volume and length. Conclusions Larger kidney donors were more likely to achieve an eGFR ≥60 mL/min/1.73 m2 with renal recovery over a shorter duration due to higher pre-donation and initial post-nephrectomy eGFRs. PMID:28638611

The influence of donor factors on corneal organ culture contamination.

PubMed

Gruenert, Anja K; Rosenbaum, Katja; Geerling, Gerd; Fuchsluger, Thomas A

2017-11-01

To evaluate the contamination rate and the corresponding spectrum of microbes and to identify donor risk factors for corneal organ culture contaminations. A total of 3306 organ-cultured donor corneas were included in the study. We performed a retrospective database analysis to evaluate donor factors such as gender, age, death-to-explantation interval (DEI), procurement site and cause of death and to determine their influence on donor cornea contaminations. Odds ratios (ORs) were calculated for each factor. The overall contamination rate was 7.8% (n = 259). Younger donor age (OR: 2.2, p = 0.003, chi-squared test), a DEI of more than 24 hr (OR: 1.6, p < 0.001), hospitalization prior to death (OR: 2.2, p < 0.001) and death caused by sepsis (OR: 2.7, p < 0.001) were associated with an increased risk of contamination, whereas donor gender did not have an effect on donor cornea contaminations. The most frequently isolated microbes were Enterococci (19%), Staphylococci (10.8%) and Candida (37.4%). This study helps to estimate the contamination risk of a cultured cornea based on specific donor factors. However, donors with risk factors should not be generally excluded from cornea donation. Further studies including antibiograms might clarify whether a change in the antibiotic composition of the culture medium would be useful to deal with the increasing number of multi-resistant microbes. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Screening blood donors for human immunodeficiency virus antibody: cost-benefit analysis.

PubMed Central

Eisenstaedt, R S; Getzen, T E

1988-01-01

The costs and benefits of screening blood donors for antibody to human immunodeficiency virus (HIV) are assessed. Total costs, including testing, discarding processed blood, marginal donor recruiting, notifying and evaluating positive donors, are $36,234,000 annually for 10 million donors in 1986. Screening these donors will prevent 292 cases of transfusion-transmitted acquired immune deficiency syndrome (TT-AIDS), saving the costs of therapy and loss of earnings for total benefits of $43,490,480, a benefit:cost ratio of 1.2:1. Net economic benefits of $0.73 per donor will arise from the program. Calculated benefits will rise as increased numbers of infected recipients are diagnosed with longer follow-up or as partially effective therapy increases the cost of caring for patients with AIDS. Changes in test sensitivity, follow-up procedures, estimated value of life, and testing costs will also alter these projections, but none as dramatically as a change in the overall specificity of the screening process. The cost per case of TT-AIDS prevented, $124,089, and cost per year of life extended, $10,885, are comparable to costs of other screening programs. PMID:3126676

Frequency and risk factors for donor reactions in an anonymous blood donor survey.

PubMed

Goldman, Mindy; Osmond, Lori; Yi, Qi-Long; Cameron-Choi, Keltie; O'Brien, Sheila F

2013-09-01

Adverse donor reactions can result in injury and decrease the likelihood of donor return. Reaction reports captured in the blood center's database provide an incomplete picture of reaction rates and risk factors. We performed an anonymous survey, mailed to 40,000 donors in 2008, including questions about symptoms, height, weight, sex, and donation status. Reaction rates were compared to those recorded in our database. Possible risk factors were assessed for various reactions. The response rate was 45.5%. A total of 32% of first-time and 14% of repeat donors reported having any adverse symptom, most frequently bruising (84.9 per 1000 donors) or feeling faint or weak (66.2 per 1000). Faint reactions were two to eight times higher than reported in our database, although direct comparison was difficult. Younger age, female sex, and first-time donation status were risk factors for systemic and arm symptoms. In females, low estimated blood volume (EBV) was a risk factor for systemic symptoms. Only 51% of donors who consulted an outside physician also called Canadian Blood Services. A total of 10% of first-time donors with reactions found adverse effects information inadequate. This study allowed us to collect more information about adverse reactions, including minor symptoms and delayed reactions. Based on our findings of the risk factors and frequency of adverse reactions, we are implementing more stringent EBV criteria for younger donors and providing more detailed information to donors about possible adverse effects and their management. © 2012 American Association of Blood Banks.

Vasovagal reactions in whole blood donors at 3 REDS-II blood centers in Brazil

PubMed Central

Goncalez, T. T.; Sabino, E. C.; Schlumpf, K.S.; Wright, D.J.; Leao, S.; Sampaio, D.; Takecian, P. L.; Carneiro-Proietti, AB; Murphy, E.; Busch, M.; Custer, B.

2013-01-01

Background In Brazil little is known about adverse reactions during donation and the donor characteristics that may be associated with such events. Donors are offered snacks and fluids prior to donating and are required to consume a light meal after donation. For these reasons the frequency of reactions may be different than those observed in other countries. Methods A cross-sectional study was conducted of eligible whole blood donors at three large blood centers located in Brazil between July 2007 and December 2009. Vasovagal reactions (VVRs) along with donor demographic and biometric data were collected. Reactions were defined as any presyncopal or syncopal event during the donation process. Multivariable logistic regression was performed to identify predictors of VVRs. Results Of 724,861 donor presentations, 16,129 (2.2%) VVRs were recorded. Rates varied substantially between the three centers: 53, 290 and 381 per 10,000 donations in Recife, São Paulo and Belo Horizonte, respectively. Although the reaction rates varied, the donor characteristics associated with VVRs were similar [younger age (18–29), replacement donors, first time donors, low estimated blood volume (EBV)]. In multivariable analysis controlling for differences between the donor populations in each city younger age, first-time donor status and lower EBV were the factors most associated with reactions. Conclusion Factors associated with VVRs in other locations are also evident in Brazil. The difference in VVR rates between the three centers might be due to different procedures for identifying and reporting the reactions. Potential interventions to reduce the risk of reactions in Brazil should be considered. PMID:22073941

Impact of a lung transplantation donor-management protocol on lung donation and recipient outcomes.

PubMed

Angel, Luis F; Levine, Deborah J; Restrepo, Marcos I; Johnson, Scott; Sako, Edward; Carpenter, Andrea; Calhoon, John; Cornell, John E; Adams, Sandra G; Chisholm, Gary B; Nespral, Joe; Roberson, Ann; Levine, Stephanie M

2006-09-15

One of the limitations associated with lung transplantation is the lack of available organs. To determine whether a lung donor-management protocol could increase the number of lungs for transplantation without affecting the survival rates of the recipients. We implemented the San Antonio Lung Transplant protocol for managing potential lung donors according to modifications of standard criteria for donor selection and strategies for donor management. We then compared information gathered during a 4-yr period, during which the protocol was used with information gathered during a 4-yr period before protocol implementation. Primary outcome measures were the procurement rate of lungs and the 30-d and 1-yr survival rates of recipients. We reviewed data from 711 potential lung donors. The mean rate of lung procurement was significantly higher (p < 0.0001) during the protocol period (25.5%) than during the pre-protocol period (11.5%), with an estimated risk ratio of 2.2 in favor of the protocol period. More patients received transplants during the protocol period (n = 121) than during the pre-protocol period (n = 53; p < 0.0001). Of 98 actual lung donors during the protocol period, 53 (54%) had initially been considered poor donors; these donors provided 64 (53%) of the 121 lung transplants. The type of donor was not associated with significant differences in recipients' 30-d and 1-yr survival rates or any clinical measures of adequate graft function. The protocol was associated with a significant increase in the number of lung donors and transplant procedures without compromising pulmonary function, length of stay, or survival of the recipients.

Donor acceptor electronic couplings in π-stacks: How many states must be accounted for?

NASA Astrophysics Data System (ADS)

Voityuk, Alexander A.

2006-04-01

Two-state model is commonly used to estimate the donor-acceptor electronic coupling Vda for electron transfer. However, in some important cases, e.g. for DNA π-stacks, this scheme fails to provide accurate values of Vda because of multistate effects. The Generalized Mulliken-Hush method enables a multistate treatment of Vda. In this Letter, we analyze the dependence of calculated electronic couplings on the number of the adiabatic states included in the model. We suggest a simple scheme to determine this number. The superexchange correction of the two-state approximation is shown to provide good estimates of the electronic coupling.

Efficiencies of Eu{sup 3+} ions and hydrogen atoms as donors in ZnO thin films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akazawa, Housei, E-mail: akazawa.housei@lab.ntt.co.jp

2016-09-15

The donor efficiencies of Eu{sup 3+} ions and hydrogen atoms in ZnO crystalline films were investigated with reference to that of Ga{sup 3+} ions. It was found that Eu{sup 3+} ions acted as extrinsic donors in ZnO:Eu films, yielding a resistivity of 1.8 × 10{sup −3} Ω cm at a doping level of 1 at. %. This value is comparable to one for intrinsic donors in undoped ZnO films. The conductivity was maintained as the deposition temperature was increased to 200 °C, and this is evidence for the contribution of extrinsic donors. Deposition of Ga-doped and Eu-doped ZnO films in an H{sub 2}O gasmore » flow produced oxyhydrogenated ZnO:(Ga, H) and ZnO:(Eu, H) films in which the Ga{sup 3+} and Eu{sup 3+} donors were deactivated by oxidization. Nevertheless, hydrogen donors contributed to electrical conduction yielding a resistivity of 1 × 10{sup −2} Ω cm. Postannealing in an H{sub 2} gas ambient alleviated the excessive oxidization of the films and thereby reactivated the donor action of Ga{sup 3+} and Eu{sup 3+} ions, causing the resistivity to recover to 10{sup −3} Ω cm for ZnO:(Ga, H) and 10{sup −2} Ω cm for ZnO:(Eu, H). In contrast, vacuum annealing of ZnO:(Ga, H) and ZnO:(Eu, H) films increased resistivity through removal of hydrogen donors while not affecting the oxidized condition of the samples.« less

Energy transfer and correlations in cavity-embedded donor-acceptor configurations.

PubMed

Reitz, Michael; Mineo, Francesca; Genes, Claudiu

2018-06-13

The rate of energy transfer in donor-acceptor systems can be manipulated via the common interaction with the confined electromagnetic modes of a micro-cavity. We analyze the competition between the near-field short range dipole-dipole energy exchange processes and the cavity mediated long-range interactions in a simplified model consisting of effective two-level quantum emitters that could be relevant for molecules in experiments under cryogenic conditions. We find that free-space collective incoherent interactions, typically associated with sub- and superradiance, can modify the traditional resonant energy transfer scaling with distance. The same holds true for cavity-mediated collective incoherent interactions in a weak-coupling but strong-cooperativity regime. In the strong coupling regime, we elucidate the effect of pumping into cavity polaritons and analytically identify an optimal energy flow regime characterized by equal donor/acceptor Hopfield coefficients in the middle polariton. Finally we quantify the build-up of quantum correlations in the donor-acceptor system via the two-qubit concurrence as a measure of entanglement.

ESR Experiments on a Single Donor Electron in Isotopically Enriched Silicon

NASA Astrophysics Data System (ADS)

Tracy, Lisa; Luhman, Dwight; Carr, Stephen; Borchardt, John; Bishop, Nathaniel; Ten Eyck, Gregory; Pluym, Tammy; Wendt, Joel; Witzel, Wayne; Blume-Kohout, Robin; Nielsen, Erik; Lilly, Michael; Carroll, Malcolm

In this talk we will discuss electron spin resonance experiments in single donor silicon qubit devices fabricated at Sandia National Labs. A self-aligned device structure consisting of a polysilicon gate SET located adjacent to the donor is used for donor electron spin readout. Using a cryogenic HEMT amplifier next to the silicon device, we demonstrate spin readout at 100 kHz bandwidth and Rabi oscillations with 0.96 visibility. Electron spin resonance measurements on these devices show a linewidth of 30 kHz and coherence times T2* = 10 us and T2 = 0.3 ms. We also discuss estimates of the fidelity of our donor electron spin qubit measurements using gate set tomography. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000. ESR Experiments on a Single Donor Electron in Isotopically Enriched Silicon.

Simple estimation of Förster Resonance Energy Transfer (FRET) orientation factor distribution in membranes.

PubMed

Loura, Luís M S

2012-11-19

Because of its acute sensitivity to distance in the nanometer scale, Förster resonance energy transfer (FRET) has found a large variety of applications in many fields of chemistry, physics, and biology. One important issue regarding the correct usage of FRET is its dependence on the donor-acceptor relative orientation, expressed as the orientation factor k(2). Different donor/acceptor conformations can lead to k(2) values in the 0 ≤ k(2) ≤ 4 range. Because the characteristic distance for FRET, R(0), is proportional to (k(2))1/6, uncertainties in the orientation factor are reflected in the quality of information that can be retrieved from a FRET experiment. In most cases, the average value of k(2) corresponding to the dynamic isotropic limit ( = 2/3) is used for computation of R(0) and hence donor-acceptor distances and acceptor concentrations. However, this can lead to significant error in unfavorable cases. This issue is more critical in membrane systems, because of their intrinsically anisotropic nature and their reduced fluidity in comparison to most common solvents. Here, a simple numerical simulation method for estimation of the probability density function of k(2) for membrane-embedded donor and acceptor fluorophores in the dynamic regime is presented. In the simplest form, the proposed procedure uses as input the most probable orientations of the donor and acceptor transition dipoles, obtained by experimental (including linear dichroism) or theoretical (such as molecular dynamics simulation) techniques. Optionally, information about the widths of the donor and/or acceptor angular distributions may be incorporated. The methodology is illustrated for special limiting cases and common membrane FRET pairs.

Significance of measured intraoperative portal vein flows after thrombendvenectomy in deceased donor liver transplantations with portal vein thrombosis.

PubMed

Draoua, Mark; Titze, Nicole; Gupta, Amar; Fernandez, Hoylan T; Ramsay, Michael; Saracino, Giovanna; McKenna, Gregory; Testa, Giuliano; Klintmalm, Goran B; Kim, Peter T W

2017-08-01

Adequate portal vein (PV) flow in liver transplantation is essential for a good outcome, and it may be compromised in patients with portal vein thrombosis (PVT). This study evaluated the impact of intraoperatively measured PV flow after PV thrombendvenectomy on outcomes after deceased donor liver transplantation (DDLT). The study included 77 patients over a 16-year period who underwent PV thrombendvenectomy with complete flow data. Patients were classified into 2 groups: high PV flow (>1300 mL/minute; n = 55) and low PV flow (≤1300 mL/minute; n = 22). Postoperative complications and graft survival were analyzed according to the PV flow. The 2 groups were similar in demographic characteristics. Low PV flow was associated with higher cumulative rates of biliary strictures (P = 0.02) and lower 1-, 2-, and 5-year graft survival (89%, 85%, and 68% versus 64%, 55%, and 38%, respectively; P = 0.002). There was no difference in the incidence of postoperative PVT between the groups (1.8% versus 9.1%; P = 0.19). No biliary leaks or hepatic artery thromboses were reported in either group. By multivariate analyses, age >60 years (hazard ratio [HR], 3.04, 95% confidence interval [CI], 1.36-6.82; P = 0.007) and low portal flow (HR, 2.31; 95% CI, 1.15-4.65; P = 0.02) were associated with worse survival. In conclusion, PV flow <1300 mL/minute after PV thrombendvenectomy for PVT during DDLT was associated with higher rates of biliary strictures and worse graft survival. Consideration should be given to identifying reasons for low flow and performing maneuvers to increase PV flow when intraoperative PV flows are <1300 mL/minute. Liver Transplantation 23 1032-1039 2017 AASLD. © 2017 by the American Association for the Study of Liver Diseases.

Predicting Liver Transplant Capacity Using Discrete Event Simulation

PubMed Central

Diaz, Hector Toro; Mayorga, Maria; Barritt, A. Sidney; Orman, Eric S.; Wheeler, Stephanie B.

2014-01-01

The number of liver transplants (LTs) performed in the US increased until 2006, but has since declined despite an ongoing increase in demand. This decline may be due in part to decreased donor liver quality and increasing discard of poor quality livers. We constructed a Discrete Event Simulation (DES) model informed by current donor characteristics to predict future LT trends through the year 2030. The data source for our model is the United Network for Organ Sharing database, which contains patient level information on all organ transplants performed in the US. Previous analysis showed that liver discard is increasing and that discarded organs are more often from donors who are older, obese, have diabetes, and donated after cardiac death. Given that the prevalence of these factors is increasing, the DES model quantifies the reduction in the number of LTs performed through 2030. In addition, the model estimates the total number of future donors needed to maintain the current volume of LTs, and the effect of a hypothetical scenario of improved reperfusion technology. We also forecast the number of patients on the waiting list and compare this to the estimated number of LTs to illustrate the impact that decreased LTs will have on patients needing transplants. By altering assumptions about the future donor pool, this model can be used to develop policy interventions to prevent a further decline in this life saving therapy. To our knowledge, there are no similar predictive models of future LT use based on epidemiologic trends. PMID:25391681

Current status of semen banking in the USA.

PubMed

Critser, J K

1998-05-01

Anonymous donor sperm banking has been a fundamental aspect of reproductive medicine for several decades. In 1987, >170,000 women in the USA were treated for infertility using artificial insemination. Current estimates suggest that the number of women seeking treatment for infertility has increased markedly since that time; however, there are no accurate, updated data to indicate the magnitude of that increase. Most anonymous donor sperm banks in the USA can be categorized as one of three types based upon administrative structure: (i) physician practice based; (ii) hospital/clinic based; or (iii) commercial corporations. Of these it is estimated that the most common structures are the physician office and hospital/clinic based banks. However, the largest (i.e. those processing the most units) are the for-profit corporate banks. A survey conducted in 1989 found that there were at least 135 sperm banks operating in the USA. More recent information indicates the number of banks to be somewhere between 50 and 150. Guidelines for anonymous donor sperm banking practices have been established by the American Society for Reproductive Medicine and standards have been established by the American Association of Tissue Banks (AATB). The AATB has recently established an inspection and accreditation programme and six anonymous donor banks have been accredited in the last few years. It is anticipated that mandatory registration of all donor banks will be required by the FDA in the near future with mandatory inspection and accreditation to follow shortly thereafter.

Deceased donor liver transplantation from donors with central nervous system malignancy: Experience of the Inonu University.

PubMed

Ince, Volkan; Ersan, Veysel; Ozdemir, Fatih; Barut, Bora; Koc, Cemalettin; Isik, Burak; Kayaalp, Cuneyt; Yilmaz, Sezai

2017-01-01

Liver transplantation from deceased donors with a central nervous system (CNS) malignancy has some risk of tumor transmission to the recipient. Though the risk is small, this group of donors is regarded as marginal. The use of marginal grafts may be an acceptable alternative practice in order to expand the donor pool in countries where there is a shortage of donated organs. The aim of this study was to examine and present the outcomes of liver transplantations performed using donors with a CNS tumor. Between March 2002 and July 2017, 1990 (deceased donor: n=399, 20%; living donor: n=1591, 80%) liver transplantations were performed at the center. Of the 399 deceased donors, 17 (4.2%) had a CNS tumor. The data of donors with a CNS tumor and of recipients who survived for more than 1 month (n=11) were retrospectively reviewed. Demographic data, the grade of the CNS tumor, tumor transmission to recipient data, and survival rates were analyzed. Only 2 (18%) grafts were provided locally, 6 (54%) were offered to the transplantation center after all of the national centers had declined them, and 3 (37%) were made available to us by the national coordination center for patients with a documented notification of urgency. High-grade (grade III-IV) brain tumors were detected in 7 (64%) donors, while low-grade (grade I-II) tumors were found in 2 patients. The remaining 2 donors were not pathologically graded because the diagnosis was made radiologically. The 1-, 3-, and 5-year overall and tumor-free survival of the patients was estimated at 100%, 70%, and 45%, respectively. A median survival of 40 months (range: 13-62 months) was achieved in recipients of grafts from a donor with a CNS tumor and no donor-related malignant transformation was observed.

Deceased donor liver transplantation from donors with central nervous system malignancy: Experience of the Inonu University

PubMed Central

Ince, Volkan; Ersan, Veysel; Ozdemir, Fatih; Barut, Bora; Koc, Cemalettin; Isik, Burak; Kayaalp, Cuneyt; Yilmaz, Sezai

2017-01-01

OBJECTIVE: Liver transplantation from deceased donors with a central nervous system (CNS) malignancy has some risk of tumor transmission to the recipient. Though the risk is small, this group of donors is regarded as marginal. The use of marginal grafts may be an acceptable alternative practice in order to expand the donor pool in countries where there is a shortage of donated organs. The aim of this study was to examine and present the outcomes of liver transplantations performed using donors with a CNS tumor. METHODS: Between March 2002 and July 2017, 1990 (deceased donor: n=399, 20%; living donor: n=1591, 80%) liver transplantations were performed at the center. Of the 399 deceased donors, 17 (4.2%) had a CNS tumor. The data of donors with a CNS tumor and of recipients who survived for more than 1 month (n=11) were retrospectively reviewed. Demographic data, the grade of the CNS tumor, tumor transmission to recipient data, and survival rates were analyzed. RESULTS: Only 2 (18%) grafts were provided locally, 6 (54%) were offered to the transplantation center after all of the national centers had declined them, and 3 (37%) were made available to us by the national coordination center for patients with a documented notification of urgency. High-grade (grade III-IV) brain tumors were detected in 7 (64%) donors, while low-grade (grade I-II) tumors were found in 2 patients. The remaining 2 donors were not pathologically graded because the diagnosis was made radiologically. The 1-, 3-, and 5-year overall and tumor-free survival of the patients was estimated at 100%, 70%, and 45%, respectively. CONCLUSION: A median survival of 40 months (range: 13-62 months) was achieved in recipients of grafts from a donor with a CNS tumor and no donor-related malignant transformation was observed. PMID:29270568

[Amplification of γδ T cells in PBMCs of healthy donors and osteosarcoma patients stimulated by zoledronate].

PubMed

Li, Zhao-xu; Sun, Ling-ling; Cheng, Rui-lin; Sun, Zheng-wang; Ye, Zhao-ming

2012-08-01

To investigate the amplification and cytotoxicity of γδ T cells in peripheral blood mononuclear cells (PBMCs) of healthy donors and osteosarcoma patients stimulated by zoledronate (Zol) and IL-2. PBMCs from healthy donors and osteosarcoma patients were stimulated with IL-2 and Zol+IL-2, respectively. After 14-day culture, the purity of γδ T cells was assessed by flow cytometry. The cytotoxicity of γδ T cells against target cells was analyzed using a standard lactate dehydrogenase release assay with γδ T lymphocyte-sensitive Daudi cells, γδ T lymphocyte-resistant Raji cells and human osteoblast cell line, hFOB, as the target cells. After 2-week culture ex vivo of PBMCs from healthy donors and osteosarcoma patients, compared with stimulation of IL-2, Zol+IL-2 significantly promoted the amplification of γδ T cells. In addition, γδ T cells showed the higher cytotoxicity against Daudi cells, but no cytotoxic effect on normal cells like hFOB. γδ T cells of high purity and high cytotoxicity can be obtained by the stimulation of Zol combined with IL-2 on PBMCs from healthy donors and osteosarcoma patients.

Analysis of fast chlorophyll fluorescence rise (O-K-J-I-P) curves in green fruits indicates electron flow limitations at the donor side of PSII and the acceptor sides of both photosystems.

PubMed

Kalachanis, Dimitrios; Manetas, Yiannis

2010-07-01

Limited evidence up to now indicates low linear photosynthetic electron flow and CO(2) assimilation rates in non-foliar chloroplasts. In this investigation, we used chlorophyll fluorescence techniques to locate possible limiting steps in photosystem function in exposed, non-stressed green fruits (both pericarps and seeds) of three species, while corresponding leaves served as controls. Compared with leaves, fruit photosynthesis was characterized by less photon trapping and less quantum yields of electron flow, while the non-photochemical quenching was higher and potentially linked to enhanced carotenoid/chlorophyll ratios. Analysis of fast chlorophyll fluorescence rise curves revealed possible limitations both in the donor (oxygen evolving complex) and the acceptor (Q(A)(-)--> intermediate carriers) sides of photosystem II (PSII) indicating innately low PSII photochemical activity. On the other hand, PSI was characterized by faster reduction of its final electron acceptors and their small pool sizes. We argue that the fast reductive saturation of final PSI electron acceptors may divert electrons back to intermediate carriers facilitating a cyclic flow around PSI, while the partial inactivation of linear flow precludes strong reduction of plastoquinone. As such, the photosynthetic attributes of fruit chloroplasts may act to replenish the ATP lost because of hypoxia usually encountered in sink organs with high diffusive resistance to gas exchange.

Biofilm models for the food industry: hot spots for plasmid transfer?

PubMed

Van Meervenne, Eva; De Weirdt, Rosemarie; Van Coillie, Els; Devlieghere, Frank; Herman, Lieve; Boon, Nico

2014-04-01

Biofilms represent a substantial problem in the food industry, with food spoilage, equipment failure, and public health aspects to consider. Besides, biofilms may be a hot spot for plasmid transfer, by which antibiotic resistance can be disseminated to potential foodborne pathogens. This study investigated biomass and plasmid transfer in dual-species (Pseudomonas putida and Escherichia coli) biofilm models relevant to the food industry. Two different configurations (flow-through and drip-flow) and two different inoculation procedures (donor-recipient and recipient-donor) were tested. The drip-flow configuration integrated stainless steel coupons in the setup while the flow-through configuration included a glass flow cell and silicone tubing. The highest biomass density [10 log (cells cm-²)] was obtained in the silicone tubing when first the recipient strain was inoculated. High plasmid transfer ratios, up to 1/10 (transconjugants/total bacteria), were found. Depending on the order of inoculation, a difference in transfer efficiency between the biofilm models could be found. The ease by which the multiresistance plasmid was transferred highlights the importance of biofilms in the food industry as hot spots for the acquisition of multiresistance plasmids. This can impede the treatment of foodborne illnesses if pathogens acquire this multiresistance in or from the biofilm. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Two-generation analysis of pollen flow across a landscape. I. Male gamete heterogeneity among females.

PubMed

Smouse, P E; Dyer, R J; Westfall, R D; Sork, V L

2001-02-01

Gene flow is a key factor in the spatial genetic structure in spatially distributed species. Evolutionary biologists interested in microevolutionary processess and conservation biologists interested in the impact of landscape change require a method that measures the real time process of gene movement. We present a novel two-generation (parent-offspring) approach to the study of genetic structure (TwoGener) that allows us to quantify heterogeneity among the male gamete pools sampled by maternal trees scattered across the landscape and to estimate mean pollination distance and effective neighborhood size. First, we describe the model's elements: genetic distance matrices to estimate intergametic distances, molecular analysis of variance to determine whether pollen profiles differ among mothers, and optimal sampling considerations. Second, we evaluate the model's effectiveness by simulating spatially distributed populations. Spatial heterogeneity in male gametes can be estimated by phiFT, a male gametic analogue of Wright's F(ST) and an inverse function of mean pollination distance. We illustrate TwoGener in cases where the male gamete can be categorically or ambiguously determined. This approach does not require the high level of genetic resolution needed by parentage analysis, but the ambiguous case is vulnerable to bias in the absence of adequate genetic resolution. Finally, we apply TwoGener to an empirical study of Quercus alba in Missouri Ozark forests. We find that phiFT = 0.06, translating into about eight effective pollen donors per female and an effective pollination neighborhood as a circle of radius about 17 m. Effective pollen movement in Q. alba is more restricted than previously realized, even though pollen is capable of moving large distances. This case study illustrates that, with a modest investment in field survey and laboratory analysis, the TwoGener approach permits inferences about landscape-level gene movements.

[Prevalence of Parvovirus B19 Infection in Chinese Xiamen Area Blood Donors].

PubMed

Ou, Shan-Hai; Xie, Jin-Zhen; Zhang, Ya-Li; Ni, Hong-Ying; Song, Xiu-Yu

2016-10-01

To estimate the prevalence of parvovirus B19 infection in Chinese Xiamen area blood donors. Blood samples from blood donors were tested for detection of parvovirus B19 DNA and antibody. The direct sequencing and genetype analysis of B19 DNA positive samples were performed. Six out of 10452 samples were B19 DNA positive. The viral loads of the 6 samples were between 3.59×10 2 -1.07×10 4 IU/ml; the positive rate of B19-IgM was 4.64%(50/1078) and B19-IgG was 16.79%(181/1078). The positive rate of B19-IgG increased with ages, and was not related with the sex. The overall prevalence of parvovirus B19 infection in blood donors is lower in Chinese Xiamen area than that in other areas, however, there is still a certain percentage of viremia in donors and the attention should be paid to blood safety in the future work.

Electron shuttling in phosphorus donor qubit systems

NASA Astrophysics Data System (ADS)

Jacobson, N. Tobias; Gamble, John King; Nielsen, Erik; Muller, Richard P.; Witzel, Wayne M.; Montano, Ines; Carroll, Malcolm S.

2014-03-01

Phosphorus donors in silicon are a promising qubit architecture, due in large part to their long nuclear coherence times and the recent development of atomically precise fabrication methods. Here, we investigate issues related to implementing qubits with phosphorus donors in silicon, employing an effective mass theory that non-phenomenologically takes into account inter-valley coupling. We estimate the significant sources of decoherence and control errors in this system to compute the fidelity of primitive gates and gate timescales. We include the effects of valley repopulation during the process of shuttling an electron between a donor and nearby interface or between neighboring donors, evaluating the control requirements for ensuring adiabaticity with respect to the valley sector. This work was supported in part by the LDRD program at Sandia National Labs, a multi-program laboratory managed and operated by Sandia Corp, a wholly owned subsidiary of Lockheed Martin Corp, for the U.S. DOE NNSA under contract DE-AC04-94AL85000.

Return behavior of occasional and multigallon blood donors: the role of theory of planned behavior, self-identity, and organizational variables.

PubMed

Wevers, Anne; Wigboldus, Daniël H J; van Baaren, Rick; Veldhuizen, Ingrid J T

2014-03-01

For blood establishments it is important that blood donors return for a donation. Past research has stressed the importance of theory of planned behavior (TPB) on return behavior, but self-identity (SI) and organizational variables (OVs) might play a role as well. This study added SI and OVs to the TPB to identify the determinants for return behavior. Whole blood donors (n = 2005) completed a questionnaire assessing TPB, SI, and OVs. OVs contained "perceived satisfaction with the blood bank" and "feeling pressure from the blood bank to donate blood." Return behavior over the past 2 years was dichotomized as low return (0%-50%) versus high return (51%-100%). Logistic regression analyses assessed the effects of TPB, SI, and OVs on high return, separately for occasional donors (two to 10 lifetime donations) and multigallon donors (>10 lifetime donations). Results showed that, for all donors, affective attitude was positively associated with return behavior, whereas pressure to donate blood was negatively associated with return behavior. The point estimates of self-efficacy, SI, and perceived satisfaction are high for multigallon donors, but do not reach significance. For all donors, positive feelings about donating blood stimulate return behavior, while experiencing a pressure to donate blood emanating from the blood bank was not beneficial. Results suggest that multigallon donors are more stimulated to return when they score higher on self-efficacy, SI, and perceived satisfaction. Interventions aiming at donor retention need to be carefully formulated to avoid negative effects of feeling pressure to donate blood. © 2013 American Association of Blood Banks.

Suicidal hanging donors for lung transplantation

PubMed Central

Ananiadou, Olga; Schmack, Bastian; Zych, Bartlomiej; Sabashnikov, Anton; Garcia-Saez, Diana; Mohite, Prashant; Weymann, Alexander; Mansur, Ashham; Zeriouh, Mohamed; Marczin, Nandor; De Robertis, Fabio; Simon, Andre Rüdiger; Popov, Aron-Frederik

2018-01-01

Abstract In the context of limited donor pool in cardiothoracic transplantation, utilization of organs from high risk donors, such as suicidal hanging donors, while ensuring safety, is under consideration. We sought to evaluate the outcomes of lung transplantations (LTx) that use organs from this group. Between January 2011 and December 2015, 265 LTx were performed at our center. Twenty-two recipients received lungs from donors after suicidal hanging (group 1). The remaining 243 transplantations were used as a control (group 2). Analysis of recipient and donor characteristics as well as outcomes was performed. No statistically significant difference was found in the donor characteristics between analyzed groups, except for higher incidence of cardiac arrest, younger age and smoking history of hanging donors (P < .001, P = .022 and P = .0042, respectively). Recipient preoperative and perioperative characteristics were comparable. Postoperatively in group 1 there was a higher incidence of extracorporeal life support (27.3 vs 9.1%, P = .019). There were no significant differences in chronic lung allograft dysfunction-free survival between group 1 and 2: 92.3 vs 94% at 1 year and 65.9 vs 75.5% at 3 years (P = .99). The estimated cumulative survival rate was also similar between groups: 68.2 vs 83.2% at 1 year and 68.2% versus 72% at 3 years (P = .3758). Hanging as a donor cause of death is not associated with poor mid-term survival or chronic lung allograft dysfunction following transplantation. These results encourage assessment of lungs from hanging donors, and their consideration for transplantation. PMID:29620623

Donor Hemodynamics as a Predictor of Outcomes After Kidney Transplantation From Donors After Cardiac Death.

PubMed

Allen, M B; Billig, E; Reese, P P; Shults, J; Hasz, R; West, S; Abt, P L

2016-01-01

Donation after cardiac death is an important source of transplantable organs, but evidence suggests donor warm ischemia contributes to inferior outcomes. Attempts to predict recipient outcome using donor hemodynamic measurements have not yielded statistically significant results. We evaluated novel measures of donor hemodynamics as predictors of delayed graft function and graft failure in a cohort of 1050 kidneys from 566 donors. Hemodynamics were described using regression line slopes, areas under the curve, and time beyond thresholds for systolic blood pressure, oxygen saturation, and shock index (heart rate divided by systolic blood pressure). A logistic generalized estimation equation model showed that area under the curve for systolic blood pressure was predictive of delayed graft function (above median: odds ratio 1.42, 95% confidence interval [CI] 1.06-1.90). Multivariable Cox regression demonstrated that slope of oxygen saturation during the first 10 minutes after extubation was associated with graft failure (below median: hazard ratio 1.30, 95% CI 1.03-1.64), with 5-year graft survival of 70.0% (95%CI 64.5%-74.8%) for donors above the median versus 61.4% (95%CI 55.5%-66.7%) for those below the median. Among older donors, increased shock index slope was associated with increased hazard of graft failure. Validation of these findings is necessary to determine the utility of characterizing donor warm ischemia to predict recipient outcome. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

Changing Metrics of Organ Procurement Organization Performance in Order to Increase Organ Donation Rates in the United States.

PubMed

Goldberg, D; Kallan, M J; Fu, L; Ciccarone, M; Ramirez, J; Rosenberg, P; Arnold, J; Segal, G; Moritsugu, K P; Nathan, H; Hasz, R; Abt, P L

2017-12-01

The shortage of deceased-donor organs is compounded by donation metrics that fail to account for the total pool of possible donors, leading to ambiguous donor statistics. We sought to assess potential metrics of organ procurement organizations (OPOs) utilizing data from the Nationwide Inpatient Sample (NIS) from 2009-2012 and State Inpatient Databases (SIDs) from 2008-2014. A possible donor was defined as a ventilated inpatient death ≤75 years of age, without multi-organ system failure, sepsis, or cancer, whose cause of death was consistent with organ donation. These estimates were compared to patient-level data from chart review from two large OPOs. Among 2,907,658 inpatient deaths from 2009-2012, 96,028 (3.3%) were a "possible deceased-organ donor." The two proposed metrics of OPO performance were: (1) donation percentage (percentage of possible deceased-donors who become actual donors; range: 20.0-57.0%); and (2) organs transplanted per possible donor (range: 0.52-1.74). These metrics allow for comparisons of OPO performance and geographic-level donation rates, and identify areas in greatest need of interventions to improve donation rates. We demonstrate that administrative data can be used to identify possible deceased donors in the US and could be a data source for CMS to implement new OPO performance metrics in a standardized fashion. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Prevalence of hepatitis B virus infection among blood donors at the Tamale Teaching Hospital, Ghana (2009)

PubMed Central

2012-01-01

Background Despite education and availability of drugs and vaccines, hepatitis B virus (HBV) is still the most common severe liver infection in the world accounting for >1 million annual deaths worldwide. Transfusion of infected blood, unprotected sex and mother to child transmission are 3 key transmission routes of HBV in Ghana. There is high incidence of blood demanding health situations in northern Ghana resulting from anemia, accidents, malnutrition, etc. The higher the demand, the higher the possibility of transmitting HBV through infected blood. The aim of the investigation was to estimate the prevalence of HBV in blood donors which will provide justification for interventions that will help minimize or eliminate HBV infection in Ghana. Findings We investigated the prevalence of HBV infection among blood donors at Tamale Teaching Hospital. The Wondfo HBsAg test kit was used to determine the concentration of HBsAg in 6,462 (576 voluntary and 5,878 replacement) donors as being ≥1 ng/ml. 10.79% of voluntary donors and 11.59% of replacement donors were HBsAg+. The 20-29 year group of voluntary donors was >2 times more likely to be HBsAg + than 40-60. Also the 20-29 year category of replacement donors was >4 times as likely to be HBsAg + than 50-69. Conclusions Risk of infection was age, sex and donor type dependent. The 20-29 year category had the highest prevalence of HBsAg + cases, mostly males residing within the metropolis. PMID:22357100

Prevalence of hepatitis B virus infection among blood donors at the Tamale Teaching Hospital, Ghana (2009).

PubMed

Dongdem, Julius Tieroyaare; Kampo, Sylvanus; Soyiri, Ireneous N; Asebga, Patrick Nsobila; Ziem, Juventus B; Sagoe, Kenneth

2012-02-22

Despite education and availability of drugs and vaccines, hepatitis B virus (HBV) is still the most common severe liver infection in the world accounting for >1 million annual deaths worldwide. Transfusion of infected blood, unprotected sex and mother to child transmission are 3 key transmission routes of HBV in Ghana. There is high incidence of blood demanding health situations in northern Ghana resulting from anemia, accidents, malnutrition, etc. The higher the demand, the higher the possibility of transmitting HBV through infected blood. The aim of the investigation was to estimate the prevalence of HBV in blood donors which will provide justification for interventions that will help minimize or eliminate HBV infection in Ghana. We investigated the prevalence of HBV infection among blood donors at Tamale Teaching Hospital. The Wondfo HBsAg test kit was used to determine the concentration of HBsAg in 6,462 (576 voluntary and 5,878 replacement) donors as being ≥1 ng/ml. 10.79% of voluntary donors and 11.59% of replacement donors were HBsAg+. The 20-29 year group of voluntary donors was >2 times more likely to be HBsAg + than 40-60. Also the 20-29 year category of replacement donors was >4 times as likely to be HBsAg + than 50-69. Risk of infection was age, sex and donor type dependent. The 20-29 year category had the highest prevalence of HBsAg + cases, mostly males residing within the metropolis.

Cystatin C-Based Equation Does Not Accurately Estimate the Glomerular Filtration in Japanese Living Kidney Donors.

PubMed

Tsujimura, Kazuma; Ota, Morihito; Chinen, Kiyoshi; Adachi, Takayuki; Nagayama, Kiyomitsu; Oroku, Masato; Nishihira, Morikuni; Shiohira, Yoshiki; Iseki, Kunitoshi; Ishida, Hideki; Tanabe, Kazunari

2017-06-23

BACKGROUND Precise evaluation of a living donor's renal function is necessary to ensure adequate residual kidney function after donor nephrectomy. Our aim was to evaluate the feasibility of estimating glomerular filtration rate (GFR) using serum cystatin-C prior to kidney transplantation. MATERIAL AND METHODS Using the equations of the Japanese Society of Nephrology, we calculated the GFR using serum creatinine (eGFRcre) and cystatin C levels (eGFRcys) for 83 living kidney donors evaluated between March 2010 and March 2016. We compared eGFRcys and eGFRcre values against the creatinine clearance rate (CCr). RESULTS The study population included 27 males and 56 females. The mean eGFRcys, eGFRcre, and CCr were, 91.4±16.3 mL/min/1.73 m² (range, 59.9-128.9 mL/min/1.73 m²), 81.5±14.2 mL/min/1.73 m² (range, 55.4-117.5 mL/min/1.73 m²) and 108.4±21.6 mL/min/1.73 m² (range, 63.7-168.7 mL/min/1.73 m²), respectively. eGFRcys was significantly lower than CCr (p<0.001). The correlation coefficient between eGFRcys and CCr values was 0.466, and the mean difference between the two values was -17.0 (15.7%), with a root mean square error of 19.2. Thus, eGFRcre was significantly lower than CCr (p<0.001). The correlation coefficient between eGFRcre and CCr values was 0.445, and the mean difference between the two values was -26.9 (24.8%), with a root mean square error of 19.5. CONCLUSIONS Although eGFRcys provided a better estimation of GFR than eGFRcre, eGFRcys still did not provide an accurate measure of kidney function in Japanese living kidney donors.

Correlation of the Glomerular Filtration Rate Measured With the Use of DTPA-Tc99m in Live Kidney Donors With Equations Based on Creatinine and Cystatin C.

PubMed

Garcia-Covarrubias, L; Barragan, J; Castro, I; Hernandez, K; Reding, A; Hinojosa, H; Prieto, P; Garcia, A; Alejandra, C; Ortuño, D; Carmona, M; Fernández, D; Diliz, H

2018-03-01

Renal donation leads to a risk of developing chronic kidney disease, with an incidence of 0.47%. To evaluate for its presence, formulas based on serum creatinine are used, but up to 80% of these formulas underestimate the glomerular filtration rate (GFR) in donors. The aim of this work was to confirm the highest correlation of the GFR as measured with the use of DTPA-Tc99m with the GFR as estimated by means of the formula based on serum cystatin C (CKD-EPI creatinine-cystatin C) in healthy kidney donors. In this observational, analytic, cross-sectional study, the GFR of kidney donors was determined ≥1 year after donation by means of DTPA gammagram and estimation with the use of conventional formulations and with cystatin C. Of 112 donors, 38 (34%) were included, 20 (60%) were female, with an overall average age of 40 years, 36.5 months after donation, and body mass index of 25.5 kg/m 2 . Correlation with the GFR as measured by means of DTPA gammagram was better with the use of CKD-EPI cystatin C (0.402; P = .020) and CKD-EPI creatinine-cystatin (0.549; P < .001) than the conventional formulas. Linear correlation with serum cystatin C was 0.825 (P < .001; 95% confidence interval, -105.3 to -63.2) for the CKD-EPI cystatin C formula, 0.77 (P < .001; -89.9 to -48.1) for the CKD-EPI creatinine-cystatin formula, and 0.525 (P = .002; -91.1 to -23.2) for DTPA-Tc99m scintigraphy. There is a strong correlation between estimate the GFR by equations based on cystatin C and the measurement of the GFR by DTPA-Tc99m gammagram. Copyright © 2017 Elsevier Inc. All rights reserved.

Validation of graft and standard liver size predictions in right liver living donor liver transplantation.

PubMed

Chan, See Ching; Lo, Chung Mau; Chok, Kenneth S H; Sharr, William W; Cheung, Tan To; Tsang, Simon H Y; Chan, Albert C Y; Fan, Sheung Tat

2011-12-01

To assess the accuracy of a formula derived from 159 living liver donors to estimate the liver size of a normal subject: standard liver weight (g) = 218 + body weight (kg) × 12.3 + 51 (if male). Standard liver volume (SLV) is attained by a conversion factor of 1.19 mL/g. The total liver volume (TLV) of each of the subsequent consecutive 126 living liver donors was determined using the right liver graft weight (RGW) on the back table, right/left liver volume ratio on computed tomography, and the conversion factor. The estimated right liver graft weight (ERGW) was determined by the right liver volume on computed tomography (CT) and the conversion factor. SLV and ERGW were compared with TLV and RGW, respectively, by paired sample t test. Donor characteristics of both series were similar. SLV and TLV were 1,099.6 ± 139.6 and 1,108.5 ± 175.2 mL, respectively, ( R 2  = 0.476) ( p  = 0.435). The difference between SLV and TLV was only -8.9 ± 128.2 mL (-1.0 ± 11.7%). ERGW and RGW were 601.5 ± 104.1 and 597.1 ± 102.2 g, respectively ( R 2  = 0.781) ( p  = 0.332). The conversion factor from liver weight to volume for this series was 1.20 mL/g. The difference between ERGW and RGW was 4.3 ± 49.8 g (0.3 ± 8.8%). ERGW was smaller than RGW for over 10% (range 0.21-40.66 g) in 18 of the 126 donors. None had the underestimation of RGW by over 20%. SLV and graft weight estimations were accurate using the formula and conversion factor.

Donor cytomegalovirus status influences the outcome of allogeneic stem cell transplant: a study by the European group for blood and marrow transplantation.

PubMed

Ljungman, Per; Brand, Ronald; Hoek, Jennifer; de la Camara, Rafael; Cordonnier, Catherine; Einsele, Hermann; Styczynski, Jan; Ward, Katherine N; Cesaro, Simone

2014-08-15

The use of a cytomegalovirus (CMV)-seronegative donor for a CMV-seronegative allogeneic hematopoietic stem cell transplant (HSCT) recipient is generally accepted. However, the importance of donor serostatus in CMV-seropositive patients is controversial. A total of 49 542 HSCT patients, 29 349 seropositive and 20 193 seronegative, were identified from the European Group for Blood and Marrow Transplantation database. Cox multivariate models were fitted to estimate the effect of donor CMV serological status on outcome. Seronegative patients receiving seropositive unrelated-donor grafts had decreased overall survival (hazard ratio [HR], 1.13; 95% confidence interval [CI], 1.06-1.21; P < .0001) compared with seronegative donors, whereas no difference was seen in patients receiving HLA-matched sibling grafts. Seropositive patients receiving grafts from seropositive unrelated donors had improved overall survival (HR, 0.92; 95% CI, .86-.98; P < .01) compared with seronegative donors, if they had received myeloablative conditioning. This effect was absent when they received reduced-intensity conditioning. No effect was seen in patients grafted from HLA-identical sibling donors. The same association was found if the study was limited to patients receiving transplants from the year 2000 onward. We confirm the negative impact on overall survival if a CMV-seropositive unrelated donor is selected for a CMV-seronegative patient. For a CMV-seropositive patient, our data support selecting a CMV-seropositive donor if the patient receives a myeloablative conditioning regimen. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Gout after living kidney donation: Correlations with demographic traits and renal complications

PubMed Central

Lam, Ngan N.; Garg, Amit X.; Segev, Dorry L.; Schnitzler, Mark A.; Xiao, Huiling; Axelrod, David; Brennan, Daniel C.; Kasiske, Bertram L.; Tuttle-Newhall, Janet E.; Lentine, Krista L.

2015-01-01

Background The demographic and clinical correlates of gout after living kidney donation are not well described. Methods Using a unique database that integrates national registry identifiers of U.S. living kidney donors (1987-2007) with billing claims from a private health insurer (2000-2007), we identified post-donation gout based on medical diagnosis codes or pharmacy fills for gout therapies. The frequencies and demographic correlates of gout after donation were estimated by Cox regression with left- and right-censoring. We also compared rates of renal diagnoses among donors with and without gout, matched 1:3 by age, sex, and race. Results The study sample of 4,650 donors included 13.1% African-Americans. By seven years, African-Americans were almost twice as likely to develop gout as Caucasian donors (4.4% vs. 2.4%; adjusted hazard ratio, aHR, 1.8; 95% confidence interval, CI, 1.0–3.2). Post-donation gout risk also increased with older age at donation (aHR per year 1.05) and was higher in men (aHR 2.80). Gout rates were similar in donors and age- and sex-matched general non-donors (rate ratio 0.86, 95% CI 0.66–1.13). Compared to matched donors without gout, donors with gout had more frequent renal diagnoses, reaching significance for acute kidney failure (rate ratio 12.5; 95% CI 1.5–107.0), chronic kidney disease (rate ratio 5.0; 95% CI 2.1–11.7), and other disorders of the kidney (rate ratio 2.2; 95% CI 1.2–4.2). Conclusion Donor subgroups at increased risk of gout include African-Americans, older donors, and men. Donors with gout have a higher burden of renal complications after demographic adjustment. PMID:25896309

Associations of recipient illness history with hypertension and diabetes after living kidney donation.

PubMed

Lentine, Krista L; Schnitzler, Mark A; Xiao, Huiling; Davis, Connie L; Axelrod, David; Abbott, Kevin C; Salvalaggio, Paolo R; Burroughs, Thomas E; Saab, Georges; Brennan, Daniel C

2011-06-15

Little is known about associations of family health history with outcomes after kidney donation. Using a database wherein Organ Procurement and Transplantation Network identifiers for 4650 living kidney donors in 1987 to 2007 were linked to administrative data of a US private health insurer (2000-2007 claims), we examined associations of recipient illness history as a measure of family history with postdonation diagnoses and drug-treatment for hypertension and diabetes. Cox regression with left and right censoring was applied to estimate associations (adjusted hazards ratios, aHR) of recipient illness history with postnephrectomy donor diagnoses, stratified by donor-recipient relationship. Recipient end-stage renal disease from hypertension, as compared with other recipient end-stage renal disease causes, was associated with modest, significant increases in the age- and gender-adjusted relative risks of hypertension diagnosis (aHR, 1.37%; 95% confidence interval [CI], 1.08-1.74) after donor nephrectomy among related donors. After adjustment for age, gender, and race, recipient type 2 diabetes compared with non-diabetic recipient status was associated with twice the relative risk of postdonation diabetes (aHR, 2.14; 95% CI, 1.28-3.55; P=0.003) among related donors. These patterns were significant among white but not among non-white related donors. Recipient type 1 diabetes was associated with postdonation diabetes only in black related donors (aHR, 3.22; 95% CI, 1.04-9.98; P=0.04). Recipient illness did not correlate significantly with outcomes in unrelated donors. These data support a need for further study of family health history as a potential sociodemographic correlate of donor outcomes, including examination of potential mediating factors and variation in risk discrimination among donors of different racial groups.

Analyzing actual risk in malaria-deferred donors through selective serologic testing.

PubMed

Nguyen, Megan L; Goff, Tami; Gibble, Joan; Steele, Whitney R; Leiby, David A

2013-08-01

Approximately 150,000 US blood donors are deferred annually for travel to malaria-endemic areas. However, the majority do not travel to the high-risk areas of Africa associated with transfusion-transmitted malaria (TTM) but visit low-risk areas such as Mexico. This study tests for Plasmodium infection among malaria-deferred donors, particularly those visiting Mexico. Blood donors deferred for malaria risk (travel, residence, or previous infection) provided blood samples and completed a questionnaire. Plasma was tested for Plasmodium antibodies by enzyme immunoassay (EIA); repeat-reactive (RR) samples were considered positive and tested by real-time polymerase chain reaction (PCR). Accepted donors provided background testing data. During 2005 to 2011, a total of 5610 malaria-deferred donors were tested by EIA, including 5412 travel deferrals. Overall, 88 (1.6%) were EIA RR; none were PCR positive. Forty-nine (55.7%) RR donors previously had malaria irrespective of deferral category, including 34 deferred for travel. Among 1121 travelers to Mexico, 90% visited Quintana Roo (no or very low risk), but just 2.2% visited Oaxaca/Chiapas (moderate or high risk). Only two Mexican travelers tested RR; both previously had malaria not acquired in Mexico. Travel to Mexico represents a large percentage of US donors deferred for malaria risk; however, these donors primarily visit no- or very-low-risk areas. No malaria cases acquired in Mexico were identified thereby supporting previous risk estimates. Consideration should be given to allowing blood donations from U.S. donors who travel to Quintana Roo and other low-risk areas in Mexico. A more effective approach to preventing TTM would be to defer all donors with a history of malaria, even if remote. © 2012 American Association of Blood Banks.

POTENTIAL IMPACT ON BLOOD AVAILABILITY AND DONOR IRON STATUS OF CHANGES TO DONOR HEMOGLOBIN CUTOFF AND INTERDONATION INTERVALS

PubMed Central

Spencer, Bryan R.; Johnson, Bryce; Wright, David J.; Kleinman, Steven; Glynn, Simone A.; Cable, Ritchard G.

2016-01-01

BACKGROUND A minimum male hemoglobin (Hb) of 13.0 g/dL will become an FDA requirement in May 2016. In addition, extending whole blood (WB) interdonation intervals (IDIs) beyond 8 weeks has been considered in order to reduce iron depletion in repeat blood donors. This study estimates the impact these changes might have on blood availability and donor iron status. STUDY DESIGN AND METHODS Six blood centers participating in REDS-II collected information on all donation visits from 2006–09. Simulations were developed from these data using a multi-stage approach that first sought to adequately reproduce the patterns of donor return, Hb and ferritin levels, and outcomes of a donor’s visit (successful single or double RBC donation, deferral for low Hb) observed in REDS-II datasets. Modified simulations were used to predict the potential impact on the blood supply and donor iron status under different Hb cutoff and IDI qualification criteria. RESULTS More than 10% of WB donations might require replacement under many simulated scenarios. Longer IDIs would reduce the proportion of donors with iron depletion, but 80% of these donors may remain iron-depleted if minimal IDIs increased to 12 or 16 weeks. CONCLUSION Higher Hb cutoffs and longer IDIs are predicted to have a potentially large impact on collections but only a modest impact on donor iron depletion. Efforts to address iron depletion should be targeted to at-risk donors, such as iron supplementation programs for frequent donors, and policy makers should try to avoid broadly restrictive donation requirements that could substantially reduce blood availability. PMID:27237451

Impact of Preoperative Abdominal Visceral Adipose Tissue Area and Nutritional Status on Renal Function After Donor Nephrectomy in Japanese Living Donors for Renal Transplantation.

PubMed

Hori, Shunta; Miyake, Makito; Morizawa, Yosuke; Nakai, Yasushi; Onishi, Kenta; Iida, Kota; Gotoh, Daisuke; Anai, Satoshi; Torimoto, Kazumasa; Aoki, Katsuya; Yoneda, Tatsuo; Tanaka, Nobumichi; Yoshida, Katsunori; Fujimoto, Kiyohide

2018-05-29

BACKGROUND Living kidney donors face the risk of renal dysfunction, resulting in end-stage renal disease, cardiovascular disease, or cerebrovascular disease, after donor nephrectomy. Reducing this risk is important to increasing survival of living donors. In this study, we investigated the effect of preoperative distribution of abdominal adipose tissue and nutritional status on postoperative renal function in living donors. MATERIAL AND METHODS Seventy-five living donors were enrolled in this retrospective study. Preoperative unenhanced computed tomography images were used to measure abdominal adipose tissue parameters. Prognostic nutritional index (PNI) was used to assess preoperative nutritional status. Donors were divided into 2 groups according to abdominal visceral adipose tissue (VAT) area at the level of the fourth and fifth lumbar vertebrae (<80 or ≥80 cm²). Postoperative renal function was compared in the 2 groups, and prognostic factors for development of chronic kidney disease (CKD) G3b were identified using multivariate analysis. RESULTS Donors with a VAT area ≥80 significantly more often had hypertension preoperatively. Although there was no significant difference in preoperative estimated glomerular filtration rate (eGFR) between the 2 groups, postoperative renal function was significantly decreased in donors with a VAT area ≥80 compared to those with a VAT area <80. In multivariate analysis, VAT area ≥80 and PNI <54 were independent factors predicting the development of CKD G3b after 12 months. CONCLUSIONS Our findings suggest that preoperative VAT and PNI affect postoperative renal function. Further research is required to establish appropriate exercise protocols and nutritional interventions during follow-up to improve outcomes in living donors.

Carbon fixation in sediments of Sino-Pacific seas-differential contributions of bacterial and archaeal domains

NASA Astrophysics Data System (ADS)

Das, Anindita; Cao, Wenrui; Zhang, Hongjie; Saren, Gaowa; Jiang, Mingyu; Yu, Xinke

2017-11-01

Oceanic stretches experiencing perpetual darkness and extreme limitation of utilizable organic matter often rely on chemosynthetic carbon (C)-fixation. However, C-fixation is not limited to carbon-deplete environments alone but might also occur in varying degrees in carbon-replete locales depending on the nature and concentration of utilizable carbon, electron donors and acceptors. Quantification of microbial C-fixation and relative contribution of domains bacteria and archaea are therefore crucial. The present experiment estimates the differential rates of C-fixation by archaea and bacteria along with the effects of different electron donors. Four Sino-Pacific marine sediments from Bashi strait (Western Pacific Warm Pool), East China Sea, South China Sea and Okinawa Trough were examined. Total microbial C-uptake was estimated by doping of aqueous NaH14CO3. Total bacterial C-uptake was measured by blocking archaeal metabolism using inhibitor GC7. Archaeal contribution was estimated by subtracting total bacterial from total microbial C-uptake. Effect of electron donor addition was analyzed by spiking with ammonium, sulfide, and reduced metals. Results suggested that C-fixation in marine sediments was not the function of archaea alone, which was in contrast to results from several recent publications. C-fixing bacteria are also equally active. Often in spite of great effort of one domain to fix carbon, the system does not become net C-fixing due to equal and opposite C-releasing activity of the other domain. Thus a C-releasing bacterial or archaeal community can become C-fixing with the change of nature and concentration of electron donors.

The correlation between preoperative volumetry and real graft weight: comparison of two volumetry programs

PubMed Central

Mussin, Nadiar; Sumo, Marco; Choi, YoungRok; Choi, Jin Yong; Ahn, Sung-Woo; Yoon, Kyung Chul; Kim, Hyo-Sin; Hong, Suk Kyun; Yi, Nam-Joon; Suh, Kyung-Suk

2017-01-01

Purpose Liver volumetry is a vital component in living donor liver transplantation to determine an adequate graft volume that meets the metabolic demands of the recipient and at the same time ensures donor safety. Most institutions use preoperative contrast-enhanced CT image-based software programs to estimate graft volume. The objective of this study was to evaluate the accuracy of 2 liver volumetry programs (Rapidia vs. Dr. Liver) in preoperative right liver graft estimation compared with real graft weight. Methods Data from 215 consecutive right lobe living donors between October 2013 and August 2015 were retrospectively reviewed. One hundred seven patients were enrolled in Rapidia group and 108 patients were included in the Dr. Liver group. Estimated graft volumes generated by both software programs were compared with real graft weight measured during surgery, and further classified into minimal difference (≤15%) and big difference (>15%). Correlation coefficients and degree of difference were determined. Linear regressions were calculated and results depicted as scatterplots. Results Minimal difference was observed in 69.4% of cases from Dr. Liver group and big difference was seen in 44.9% of cases from Rapidia group (P = 0.035). Linear regression analysis showed positive correlation in both groups (P < 0.01). However, the correlation coefficient was better for the Dr. Liver group (R2 = 0.719), than for the Rapidia group (R2 = 0.688). Conclusion Dr. Liver can accurately predict right liver graft size better and faster than Rapidia, and can facilitate preoperative planning in living donor liver transplantation. PMID:28382294

Population-based screening for anemia using first-time blood donors

PubMed Central

Mast, Alan E.; Steele, Whitney R.; Johnson, Bryce; Wright, David J.; Cable, Ritchard G.; Carey, Patricia; Gottschall, Jerome L.; Kiss, Joseph E.; Simon, Toby L.; Murphy, Edward L.

2012-01-01

Background Anemia is an important public health concern. Data from population-based surveys such as the National Health and Nutrition Examination Survey (NHANES) are the gold standard, but are obtained infrequently and include only small samples from certain minority groups. Objectives We assessed whether readily available databases of blood donor hemoglobin values could be used as a surrogate for population hemoglobin values from NHANES. Design Blood donor venous and fingerstick hemoglobin values were compared to 10,254 NHANES 2005-2008 venous hemoglobin values using demographically stratified analyses and ANOVA. Fingerstick hemoglobins or hematocrits were converted to venous hemoglobin estimates using regression analysis. Results Venous hemoglobin values from 1,609 first time donors correlated extremely well with NHANES data across different age, gender and demographic groups. Cigarette smoking increased hemoglobin by 0.26 to 0.59 g/dL depending on intensity. Converted fingerstick hemoglobin from 36,793 first time donors agreed well with NHANES hemoglobin (weighted mean hemoglobin of 15.53 g/dL for donors and 15.73 g/dL for NHANES) with similar variation in mean hemoglobin by age. However, compared to NHANES, the larger donor dataset showed reduced differences in mean hemoglobin between Blacks and other races/ethnicities. Conclusions Overall, first-time donor fingerstick hemoglobins approximate U.S. population data and represent a readily available public health resource for ongoing anemia surveillance. PMID:22460662

Dual-phase gas-permeation flow-injection thermometric analysis for the determination of carbon dioxide.

PubMed

Liu, S J; Tubino, M

1998-11-01

A flow-injection configuration based on a dual-phase gas-permeation system from a liquid donor to a gas acceptor stream with a thermistor flow-through detector is proposed for the direct analysis of the gas in the acceptor. This system was applied for the determination of carbon dioxide (in the form of carbonate) using the following chemical reaction: CO(2)(g)+2NH(3)(g)+H(2)O(g)=(NH(4))(2)CO(3)(s), with a linear response from 1x10(-3) to 50x10(-3) mol l(-1) of CO(3)(2-). Carbon dioxide was produced in the liquid donor and permeated into the gaseous acceptor stream of air/water vapor. The detection limit is 1x10(-3) mol l(-1) of carbonate, and a sampling frequency of 60 h(-1) is achieved with a relative standard deviation of 4.1% for replicate injections. The dual-phase gas-permeation flow-injection manifold, along with the membrane and phase separations, as well as the chemical reaction, provides enhanced selectivity when compared with the system employing a liquid acceptor stream, as serious interferents in this system, for instance, acetate and formate, among others, do not interfere in the proposed system.

Regional myocardial shape and dimensions of the working isolated canine left ventricle

NASA Technical Reports Server (NTRS)

Ritman, E.; Tsuiki, K.; Donald, D.; Wood, E. H.

1975-01-01

Angiographic experiments were performed on isolated canine left ventricle preparations using donor dog to supply blood to the coronary circulation via a rotary pump to control coronary flow. The angiographic record was transferred from video tape to video disk for detailed uninterrupted sequential analysis at a frequency of 60 fields/sec. It is shown that the use of a biplane X-ray technique and a metabolically supported isolated canine left ventricle preparation provides an angiographically ideal means of measuring the mechanical dynamics of the myocardium while the intact left ventricular myocardial structure and electrical activation pattern retain most of the in situ ventricular characteristics. In particular, biplane X-ray angiography of the left ventricle can provide estimates of total ventricular function such as ejection fraction, stroke volume, and myocardial mass correct to within 15% under the angiographically ideal conditions of the preparation.

Estimation of total glomerular number in stable renal transplants.

PubMed

Fulladosa, Xavier; Moreso, Francesc; Narváez, Jose A; Grinyó, Josep M; Serón, Daniel

2003-10-01

Glomerular number (N(g)) is considered a major determinant of renal function and outcome. In the dog, it has been shown that Ng can be estimated with reasonable precision in vivo by means of a renal biopsy and magnetic resonance imaging (MRI). Thus, this method was applied to study anatomoclinical correlations in stable human renal transplants. Thirty-nine stable renal transplants were included. A protocol renal allograft biopsy was done at 4 mo. Biopsies were evaluated according to Banff criteria. Glomerular volume fraction (Vv(glom/cortex)) was measured by means of a point-counting method, and mean glomerular volume (V(g)) was estimated by means of Weibel and Gomez (V(g)-W&G) and maximal profile area (V(g)-MPA) methods. MRI was used to estimate renal cortical volume (V(cortex)). N(g) was calculated as (Vv(glom/cortex) x V(cortex))/V(g). GFR was estimated by the inulin clearance. Ten age-matched donor biopsies served as controls for V(g). Histologic diagnosis was as follows: normal (n = 20), borderline (n = 7), acute rejection (n = 1), and chronic allograft nephropathy (n = 11). Vv(glom/cortex) was 3.4 +/- 1.1%, V(cortex) was 167 +/- 46 cm(3), V(g)-W&G was 3.2 +/- 1.2 x 10(6) micro m(3), and V(g)-MPA was 3.3 +/- 1.0 x 10(6) micro m(3). V(g)-W&G in donor and recipient biopsies was not different (3.6 +/- 1.1 versus 3.2 +/- 1.2 x 10(6) micro m(3)). Total glomerular number estimated by means of V(g)-W&G (N(g)-W&G) was 0.73 +/- 0.33 x 10(6) and by V(g)-MPA (N(g)-MPA) was 0.74 +/- 0.31 x 10(6). A positive correlation between GFR and N(g)-W&G (r = 0.47, P = 0.002) was observed. Furthermore, the older the donor, the higher V(g)-W&G (r = 0.37, P = 0.01) and the lower N(g)-W&G (r = -0.40, P = 0.01). Total glomerular number can be estimated in stable renal allografts by means of a renal biopsy and MRI. Our data show that N(g) depends on donor age and positively correlates with GFR.

Health spending, illicit financial flows and tax incentives in Malawi.

PubMed

O'Hare, B; Curtis, M

2014-12-01

This analysis examines the gaps in health care financing in Malawi and how foregone taxes could fill these gaps. It begins with an assessment of the disease burden and government health expenditure. Then it analyses the tax revenues foregone by the government of Malawi by two main routes: Illicit financial flows (IFF) from the country, Tax incentives. We find that there are significant financing gaps in the health sector; for example, government expenditure is United States Dollars (USD) 177 million for 2013/2014 while projected donor contribution in 2013/2014 is USD 207 million and the total cost for the minimal health package is USD 535 million. Thus the funding gap between the government budget for health and the required spending to provide the minimal package for 2013/2014 is USD 358 million. On the other hand we estimate that almost USD 400 million is lost through IFF and corporate utilization of tax incentives each year. The revenues foregone plus the current government health spending would be sufficient to cover the minimal public health package for all Malawians and would help tackle Malawi's disease burden. Every effort must be made, including improving transparency and revising laws, to curtail IFF and moderate tax incentives.

Mineral transformation and biomass accumulation associated with uranium bioremediation at Rifle, Colorado

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, L.; Steefel, C.I.; Williams, K.H.

2009-04-20

Injection of organic carbon into the subsurface as an electron donor for bioremediation of redox-sensitive contaminants like uranium often leads to mineral transformation and biomass accumulation, both of which can alter the flow field and potentially bioremediation efficacy. This work combines reactive transport modeling with a column experiment and field measurements to understand the biogeochemical processes and to quantify the biomass and mineral transformation/accumulation during a bioremediation experiment at a uranium contaminated site near Rifle, Colorado. We use the reactive transport model CrunchFlow to explicitly simulate microbial community dynamics of iron and sulfate reducers, and their impacts on reaction rates.more » The column experiment shows clear evidence of mineral precipitation, primarily in the form of calcite and iron monosulfide. At the field scale, reactive transport simulations suggest that the biogeochemical reactions occur mostly close to the injection wells where acetate concentrations are highest, with mineral precipitate and biomass accumulation reaching as high as 1.5% of the pore space. This work shows that reactive transport modeling coupled with field data can be an effective tool for quantitative estimation of mineral transformation and biomass accumulation, thus improving the design of bioremediation strategies.« less

Mineral transformation and biomass accumulation associated with uranium bioremediation at Rifle, Colorado.

PubMed

Li, Li; Steefel, Carl I; Williams, Kenneth H; Wilkins, Michael J; Hubbard, Susan S

2009-07-15

Injection of organic carbon into the subsurface as an electron donor for bioremediation of redox-sensitive contaminants like uranium often leads to mineral transformation and biomass accumulation, both of which can alter the flow field and potentially bioremediation efficacy. This work combines reactive transport modeling with a column experiment and field measurements to understand the biogeochemical processes and to quantify the biomass and mineral transformation/accumulation during a bioremediation experiment at a uranium contaminated site near Rifle, Colorado. We use the reactive transport model CrunchFlow to explicitly simulate microbial community dynamics of iron and sulfate reducers, and their impacts on reaction rates. The column experiment shows clear evidence of mineral precipitation, primarily in the form of calcite and iron monosulfide. At the field scale, reactive transport simulations suggest that the biogeochemical reactions occur mostly close to the injection wells where acetate concentrations are highest, with mineral precipitate and biomass accumulation reaching as high as 1.5% of the pore space. This work shows that reactive transport modeling coupled with field data can bean effective tool for quantitative estimation of mineral transformation and biomass accumulation, thus improving the design of bioremediation strategies.

Impact of using different blood donor subpopulations and models on the estimation of transfusion transmission residual risk of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus in Zimbabwe.

PubMed

Mapako, Tonderai; Janssen, Mart P; Mvere, David A; Emmanuel, Jean C; Rusakaniko, Simbarashe; Postma, Maarten J; van Hulst, Marinus

2016-06-01

Various models for estimating the residual risk (RR) of transmission of infections by blood transfusion have been published mainly based on data from high-income countries. However, to obtain the data required for such an assessment remains challenging for most developing settings. The National Blood Service Zimbabwe (NBSZ) adapted a published incidence-window period (IWP) model, which has less demanding data requirements. In this study we assess the impact of various definitions of blood donor subpopulations and models on RR estimates. We compared the outcomes of two published models and an adapted NBSZ model. The Schreiber IWP model (Model 1), an amended version (Model 2), and an adapted NBSZ model (Model 3) were applied. Variably the three models include prevalence, incidence, preseroconversion intervals, mean lifetime risk, and person-years at risk. Annual mean RR estimates and 95% confidence intervals for each of the three models for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) were determined using NBSZ blood donor data from 2002 through 2011. The annual mean RR estimates for Models 1 through 3 were 1 in 6542, 5805, and 6418, respectively for HIV; 1 in 1978, 2027, and 1628 for HBV; and 1 in 9588, 15,126, and 7750, for HCV. The adapted NBSZ model provided comparable results to the published methods and these highlight the high occurrence of HBV in Zimbabwe. The adapted NBSZ model could be used as an alternative to estimate RRs when in settings where two repeat donations are not available. © 2016 AABB.

Direct peritoneal resuscitation improves inflammation, liver blood flow, and pulmonary edema in a rat model of acute brain death.

PubMed

Smith, Jason W; Ghazi, Cameron A; Cain, Brandon C; Hurt, Ryan T; Garrison, R Neal; Matheson, Paul J

2014-07-01

Brain death in organ donors alters central hemodynamic performance, impairs physiology, exaggerates inflammation, and causes end-organ microcirculatory dysfunction and hypoxia. A new treatment, direct peritoneal resuscitation (DPR), might improve these derangements in acute brain death (ABD). We studied a standardized rodent model of brain death with matched controls to assess the efficacy of DPR as a resuscitation strategy after ABD. Anesthetized Sprague-Dawley rats were randomized as follows: ABD (supradural balloon inflation) with minimal IV fluid (IVF; 2 mL/h, n = 12); ABD + adequate IVF (5 mL/h, n = 12); ABD with aggressive IVF (goal: mean arterial pressure [MAP] >80 mmHg, n = 15); or ABD + IVF + DPR (goal: MAP >80 mmHg, n = 12). Ventilation support, IVF, and DPR were started at loss of reflexes, and MAP, heart rate, and effective hepatic blood flow were recorded. High IVF and DPR prevented mortality (0%) compared with low IVF (81.8%) or mid IVF (16.7%). Effective hepatic blood flow was decreased in low and mid IVF (2.8 ± 0.3 mL/min/g body weight and 4.0 ± 0.5 mL/min/g body weight, respectively) vs baseline, but was stable in high IVF (6.2 ± 0.5 mL/min/g body weight; NS) or improved with DPR (8.6 ± 0.7 mL/min/g body weight). The high-IVF group had significant organ edema, which was prevented in the DPR group. The mid-IVF and low-IVF groups had higher serum markers of organ injury compared with high-IVF or DPR groups. The high-IVF group had elevated inflammatory cytokines compared with the DPR group. Direct peritoneal resuscitation improved survival and effective hepatic blood flow, required less IVF to stabilize blood pressure, prevented organ edema, and normalized fluid electrolyte balance compared with IVF-alone groups. Direct peritoneal resuscitation in animals reduced inflammatory response after ABD compared with IVF-alone controls. These data suggest a potential role for DPR in organ donors to stabilize donors and possibly increase the number of organs suitable for transplantation per donor. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

A and B antigen levels acquired by group O donor-derived erythrocytes following ABO-non-identical transfusion or minor ABO-incompatible haematopoietic stem cell transplantation.

PubMed

Hult, A K; Dykes, J H; Storry, J R; Olsson, M L

2017-06-01

ABO-incompatible haematopoietic stem cell transplantation (HSCT) presents a challenge to blood component transfusion. The aim of this study was to investigate the weak blood group A or B antigen expression by donor-derived group O red blood cells (RBC) observed following transfusion or minor ABO-incompatible HSCT. In addition, in vitro experiments were performed to elucidate possible mechanisms underlying this phenomenon. A sensitive flow cytometry assay for the semi-quantification of RBC A/B antigen levels was used to assess patient samples and evaluate in vitro experiments. Analysis of blood samples from patients, originally typed as A, B and AB but recently transplanted or transfused with cells from group O donors, revealed the A antigen expression on donor-derived RBC, ranging from very low levels in non-secretor individuals to almost subgroup A x -like profiles in group A secretors. The B antigen expression was less readily detectable. In vitro experiments, in which group O donor RBC were incubated with (i) group A/B secretor/non-secretor donor plasma or (ii) group A/B donor RBC in the absence of plasma, supported the proposed adsorption of A/B antigen-bearing glycolipids from secretor plasma but also indicated a secretor-independent mechanism for A/B antigen acquisition as well as direct cell-to-cell transfer of ABO antigens. The in vivo conversion of donor-derived blood group O RBC to ABO subgroup-like RBC after transfusion or minor ABO-incompatible HSCT raises the question of appropriate component selection. Based on these data, AB plasma should be transfused following ABO-incompatible HSCT. © 2017 British Blood Transfusion Society.

Distinct Contributory Factors Determine Basophil-Allergen Sensitivity in Grass Pollen Rhinitis and in Anaphylactic Wasp Venom Allergy.

PubMed

Korošec, Peter; Šilar, Mira; Kopač, Peter; Eržen, Renato; Zidarn, Mihaela; Košnik, Mitja

2016-01-01

We sought to determine whether basophil-allergen sensitivity could be transferred to donor basophils by passive IgE sensitisation in allergic rhinitis and anaphylactic Hymenoptera venom hypersensitivity. We studied 15 wasp venom-, 19 grass pollen- and 2 house dust mite-allergic patients, 2 healthy donors, and 8 wasp venom-allergic donors. In all subjects, we first evaluated the initial basophil response to wasp venom, grass pollen, or house dust mite allergen. Donor basophils were then stripped, sensitised with the different patients' serum IgE, and challenged with the corresponding allergen. The CD63 response of donor basophils was then compared with initial basophil responses. In wasp venom-allergic subjects, the IgE transfer did not reflect the initial basophil-allergen sensitivity, because the venom IgE of subjects with high or low basophil sensitivity induced comparable responsiveness in healthy donor basophils. Furthermore, vice versa, when we sensitised the donor basophils of wasp venom-allergic individuals with different wasp venom or house dust mite IgE, we demonstrated that their response was predictable by their initial basophil allergen sensitivity. In the rhinitis allergy model, the IgE transfer correlated with the patients' initial basophil responsiveness because the grass pollen IgE of the subjects with high basophil allergen sensitivity induced significantly higher responsiveness of donor basophils than the IgE of subjects with initially low basophil allergen sensitivity. Our results suggest that basophil allergen sensitivity evaluated by flow-cytometric CD63 analysis depends on two distinct contribution factors. In anaphylactic Hymenoptera allergy, the major factor was intrinsic cellular sensitivity, whereas in pollen allergy, the major factor was allergen-specific IgE on the cell surface. © 2016 S. Karger AG, Basel.

Stem cell collection in unmanipulated HLA-haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised blood and bone marrow for patients with haematologic malignancies: the impact of donor characteristics and procedural settings.

PubMed

Zhang, C; Chen, X-H; Zhang, X; Gao, L; Gao, L; Kong, P-Y; Peng, X-G; Sun, A-H; Gong, Y; Zeng, D-F; Wang, Q-Y

2010-06-01

Unmanipulated haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised peripheral blood stem cells (G-PBSCs) and granulocyte-colony stimulating factor-mobilised bone marrow (G-BM) has been developed as an alternative transplantation strategy for patients with haematologic malignancies. However, little information is available about the factors predicting the outcome of peripheral blood stem cell (PBSC) collection and bone marrow (BM) harvest in this transplantation. The effects of donor characteristics and procedure factors on CD34(+) cell yield were investigated. A total of 104 related healthy donors received granulocyte-colony stimulating factor (G-CSF) followed by PBSC collection and BM harvest. Male donors had significantly higher yields compared with female donors. In multiple regression analysis for peripheral blood collection, age and flow rate were negatively correlated with cell yield, whereas body mass index, pre-aphaeresis white blood cell (WBC) and circulating immature cell (CIC) counts were positively correlated with cell yields. For BM harvest, age was negatively correlated with cell yields, whereas pre-BM collection CIC counts were positively correlated with cell yield. All donors achieved the final product of >or=6 x10(6) kg(-1) recipient body weight. This transplantation strategy has been shown to be a feasible approach with acceptable outcomes in stem cell collection for patients who received HLA-haploidentical/mismatched transplantation with combined G-PBSCs and G-BM. In donors with multiple high-risk characteristics for poor aphaeresis CD34(+) cell yield, BM was an alternative source.

Outcomes of hematopoietic cell transplantation using donors or recipients with inherited chromosomally integrated HHV-6.

PubMed

Hill, Joshua A; Magaret, Amalia S; Hall-Sedlak, Ruth; Mikhaylova, Anna; Huang, Meei-Li; Sandmaier, Brenda M; Hansen, John A; Jerome, Keith R; Zerr, Danielle M; Boeckh, Michael

2017-08-24

Human herpesvirus 6 (HHV-6) species have a unique ability to integrate into chromosomal telomeres. Mendelian inheritance via gametocyte integration results in HHV-6 in every nucleated cell. The epidemiology and clinical effect of inherited chromosomally integrated HHV-6 (iciHHV-6) in hematopoietic cell transplant (HCT) recipients is unclear. We identified 4319 HCT donor-recipient pairs (8638 subjects) who received an allogeneic HCT and had archived pre-HCT peripheral blood mononuclear cell samples. We screened these samples for iciHHV-6 and compared characteristics of HCT recipients and donors with iciHHV-6 with those of recipients and donors without iciHHV-6, respectively. We calculated Kaplan-Meier probability estimates and Cox proportional hazards models for post-HCT outcomes based on recipient and donor iciHHV-6 status. We identified 60 HCT recipients (1.4%) and 40 donors (0.9%) with iciHHV-6; both recipient and donor harbored iciHHV-6 in 13 HCTs. Thus, there were 87 HCTs (2%) in which the recipient, donor, or both harbored iciHHV-6. Acute graft-versus-host disease (GVHD) grades 2-4 was more frequent when recipients or donors had iciHHV-6 (adjusted hazard ratios, 1.7-1.9; P = .004-.001). Cytomegalovirus viremia (any and high-level) was more frequent among recipients with iciHHV-6 (adjusted HRs, 1.7-3.1; P = .001-.040). Inherited ciHHV-6 status did not significantly affect risk for chronic GVHD, hematopoietic cell engraftment, overall mortality, or nonrelapse mortality. Screening for iciHHV-6 could guide donor selection and post-HCT risk stratification and treatment. Further study is needed to replicate these findings and identify potential mechanisms. © 2017 by The American Society of Hematology.

The Need for New Donor Stratification to Predict Graft Survival in Deceased Donor Kidney Transplantation.

PubMed

Yang, Shin Seok; Yang, Jaeseok; Ahn, Curie; Min, Sang Il; Ha, Jongwon; Kim, Sung Joo; Park, Jae Berm

2017-05-01

The aim of this study was to determine whether stratification of deceased donors by the United Network for Organ Sharing (UNOS) criteria negatively impacts graft survival. We retrospectively reviewed deceased donor and recipient pretransplant variables of kidney transplantations that occurred between February 1995 and December 2009. We compared clinical outcomes between standard criteria donors (SCDs) and expanded criteria donors (ECDs). The deceased donors consisted of 369 patients. A total of 494 transplant recipients were enrolled in this study. Mean age was 41.7±11.4 year (range 18-69) and 273 patients (55.4%) were male. Mean duration of follow-up was 8.8±4.9 years. The recipients from ECD kidneys were 63 patients (12.8%). The overall mean cold ischemia time was 5.7±3.2 hours. Estimated glomerular filtration rate at 1, 2, and 3 years after transplantation were significantly lower in ECD transplants (1 year, 62.2±17.6 vs. 51.0±16.4, p<0.001; 2 year, 62.2±17.6 vs. 51.0±16.4, p=0.001; 3 year, 60.9±23.5 vs. 54.1±18.7, p=0.047). In multivariate analysis, donor age (≥40 years) was an independent risk factor for graft failure. In Kaplan-Meier analyses, there was no significant difference in death-censored graft survival (Log rank test, p>0.05), although patient survival was lower in ECDs than SCDs (Log rank test, p=0.011). Our data demonstrate that stratification by the UNOS criteria does not predict graft survival. In order to expand the donor pool, new criteria for standard/expanded donors need to be modified by regional differences. © Copyright: Yonsei University College of Medicine 2017

Suicidal hanging donors for lung transplantation: Is this chapter still closed? Midterm experience from a single center in United Kingdom.

PubMed

Ananiadou, Olga; Schmack, Bastian; Zych, Bartlomiej; Sabashnikov, Anton; Garcia-Saez, Diana; Mohite, Prashant; Weymann, Alexander; Mansur, Ashham; Zeriouh, Mohamed; Marczin, Nandor; De Robertis, Fabio; Simon, Andre Rüdiger; Popov, Aron-Frederik

2018-04-01

In the context of limited donor pool in cardiothoracic transplantation, utilization of organs from high risk donors, such as suicidal hanging donors, while ensuring safety, is under consideration. We sought to evaluate the outcomes of lung transplantations (LTx) that use organs from this group.Between January 2011 and December 2015, 265 LTx were performed at our center. Twenty-two recipients received lungs from donors after suicidal hanging (group 1). The remaining 243 transplantations were used as a control (group 2). Analysis of recipient and donor characteristics as well as outcomes was performed.No statistically significant difference was found in the donor characteristics between analyzed groups, except for higher incidence of cardiac arrest, younger age and smoking history of hanging donors (P < .001, P = .022 and P = .0042, respectively). Recipient preoperative and perioperative characteristics were comparable. Postoperatively in group 1 there was a higher incidence of extracorporeal life support (27.3 vs 9.1%, P = .019). There were no significant differences in chronic lung allograft dysfunction-free survival between group 1 and 2: 92.3 vs 94% at 1 year and 65.9 vs 75.5% at 3 years (P = .99). The estimated cumulative survival rate was also similar between groups: 68.2 vs 83.2% at 1 year and 68.2% versus 72% at 3 years (P = .3758).Hanging as a donor cause of death is not associated with poor mid-term survival or chronic lung allograft dysfunction following transplantation. These results encourage assessment of lungs from hanging donors, and their consideration for transplantation.

Associations between Deceased-Donor Urine MCP-1 and Kidney Transplant Outcomes.

PubMed

Mansour, S G; Puthumana, J; Reese, P P; Hall, I E; Doshi, M D; Weng, F L; Schröppel, B; Thiessen-Philbrook, H; Bimali, M; Parikh, C R

2017-07-01

Existing methods to predict recipient allograft function during deceased-donor kidney procurement are imprecise. Understanding the potential renal reparative role for monocyte chemoattractant protein-1 (MCP-1), a cytokine involved in macrophage recruitment after injury, might help predict allograft outcomes. We conducted a sub-study of the multicenter prospective Deceased Donor Study cohort, which evaluated deceased kidney donors from five organ procurement organizations from May 2010 to December 2013. We measured urine MCP-1 (uMCP-1) concentrations from donor samples collected at nephrectomy to determine associations with donor acute kidney injury (AKI), recipient delayed graft function (DGF), 6-month estimated GFR (eGFR), and graft failure. We also assessed perfusate MCP-1 concentrations from pumped kidneys for associations with DGF and 6-month eGFR. AKI occurred in 111 (9%) donors. Median (interquartile range) uMCP-1 concentration was higher in donors with AKI compared to donors without AKI (1.35 [0.41-3.93] ng/ml vs. 0.32 [0.11-0.80] ng/ml, p<0.001). DGF occurred in 756 (31%) recipients, but uMCP-1 was not independently associated with DGF. Higher donor uMCP-1 concentrations were independently associated with higher 6-month eGFR in those without DGF [0.77 (0.10, 1.45) ml/min/1.73m 2 per doubling of uMCP1]. However, there were no independent associations between uMCP-1 and graft failure over a median follow-up of about 2 years. Lastly, perfusate MCP-1 concentrations significantly increased during pump perfusion but were not associated with DGF or 6-month eGFR. Donor uMCP-1 concentrations were modestly associated with higher recipient 6-month eGFR in those without DGF. However, the results suggest that donor uMCP-1 has minimal clinical utility given no associations with graft failure.

Mixed donor chimerism in non-malignant haematological diseases after allogeneic bone marrow transplantation.

PubMed

Shamshad, Ghassan Umair; Ahmed, Suhaib; Bhatti, Farhat Abbas; Ali, Nadir

2012-12-01

To determine the frequency of mixed donor chimerism in patients of non-malignant haematological diseases after allogeneic bone marrow transplant. A cross-sectional, observational study. Department of Haematology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from July 2010 to June 2011. Donor chimerism was assessed in patients of aplastic anaemia and beta-thalassaemia major who underwent allogeneic bone marrow transplantation (BMT). Peripheral blood samples were used to assess chimerism status by analysis of short tandem repeats (STR). In patients where pre-transplant blood sample was not available, swab of buccal mucosa was used for pre-transplant STR profile. A standard set of primers for STR markers were used and the amplified DNA was resolved by gel electrophoresis and stained with silver nitrate. The percentage of donor origin DNA was estimated by densitometer. Out of 84 patients, 52 (62%) were males, while 32 (38%) were females. In patients of beta-thalassaemia major, 31 (62%) developed mixed donor chimerism (MC), 13 (26%) developed complete donor chimerism (CC) and 6 (12%) had graft failure. In aplastic anaemia, 17 patients (50%) achieved MC, 13 (38.2%) had CC and 4 (11.8%) developed graft failure. The combined frequency of mixed donor chimerism for both the diseases was 58.3%. D3S1358 was the most informative STR marker in these patients. Majority of the studied patients developed mixed donor chimerism following bone marrow transplantation, whereas only a minor percentage of the patients had graft failure. Analysis of D3S1358 was the most informative in assessing donor chimerism in patients who underwent BMT.

Granulocyte-colony stimulating factor administration among hemoglobin S trait donors: A single center experience from the Eastern Mediterranean region.

PubMed

Gereklioglu, Cigdem; Asma, Suheyl; Korur, Aslı; Tepebaşı, Songul; Aytan, Pelin; Yeral, Mahmut; Kozanoglu, Ilknur; Boga, Can; Ozdogu, Hakan

2018-02-01

Assessment of Hemoglobin S trait donors has gained importance together with the increased allogeneic peripheral stem cell transplant activity for sickle cell disease in the regions where the disease is prevalent. Outcomes of Granulocyte-Colony Stimulating Factor (G-CSF) administration are obscure for hemoglobin S trait donors. This study aims at investigating the incidence of hemoglobin S carrier status and outcomes of G-CSF administration among donors who live in Eastern Mediterranean region. The cross-sectional, single-center cohort study was performed with 147 donors between January 2013 and March 2017. Prevalence of hemoglobin S trait was estimated and subjects with or without Hemogobin S trait were compared with regard to stem cell characteristics, early and late clinical outcomes after G-CSF administration. Eleven out of 147 donors (7.48%) were found as hemoglobin S trait. G-CSF administration was successfully completed and yielded good harvesting results in hemoglobin S trait donors. No statistically significant difference was found between groups with regard to early and late side effects, stem cell characteristics. Blood pressures and QTc values were within normal ranges in both groups. Groups were similar with regard to CD34 values. G-CSF seems safe in hemoglobin S trait donors. Their being eligible as donors would increase the chance of the patients for allogeneic stem cell transplantation in high prevalence regions. Further studies are required to reveal the safety profile of G-SCF in hemoglobin S carriers in different regions. © 2017 Wiley Periodicals, Inc.

Long-term Renal Function in Living Kidney Donors Who Had Histological Abnormalities at Donation.

PubMed

Fahmy, Lara M; Massie, Allan B; Muzaale, Abimereki D; Bagnasco, Serena M; Orandi, Babak J; Alejo, Jennifer L; Boyarsky, Brian J; Anjum, Saad K; Montgomery, Robert A; Dagher, Nabil N; Segev, Dorry L

2016-06-01

Recent evidence suggests that living kidney donors are at an increased risk of end-stage renal disease. However, predicting which donors will have renal dysfunction remains challenging, particularly among those with no clinical evidence of disease at the time of donation. Although renal biopsies are not routinely performed as part of the donor evaluation process, they may yield valuable information that improves the ability to predict renal function in donors. We used implantation protocol biopsies to evaluate the association between histological abnormalities in the donated kidney and postdonation renal function (estimated glomerular filtration rate, eGFR) of the remaining kidney in living kidney donors. Longitudinal analysis using mixed-effects linear regression was used to account for multiple eGFR measures per donor. Among 310 donors between 1997 and 2012, median (IQR) follow-up was 6.2 (2.5-8.7; maximum 14.0) years. In this cohort, the overall prevalence of histological abnormalities was 65.8% (19.7% abnormal glomerulosclerosis, 23.9% abnormal interstitial fibrosis and tubular atrophy (IFTA), 4.8% abnormal mesangial matrix increase, 32.0% abnormal arteriolar hyalinosis, and 32.9% abnormal vascular intimal thickening). IFTA was associated with a 5-mL/min/1.73 m decrease of postdonation eGFR after adjusting for donor age at donation, sex, race, preoperative systolic blood pressure, preoperative eGFR, and time since donation (P < 0.01). In this single-center study, among healthy individuals cleared for living donation, IFTA was associated with decreased postdonation eGFR, whereas no other subclinical histological abnormalities provided additional information.

Long-Term Renal Function in Living Kidney Donors who had Histological Abnormalities at Donation

PubMed Central

Fahmy, Lara M.; Massie, Allan B.; Muzaale, Abimereki D.; Bagnasco, Serena M.; Orandi, Babak J.; Alejo, Jennifer L.; Boyarsky, Brian J.; Anjum, Saad K.; Montgomery, Robert A.; Dagher, Nabil N.; Segev, Dorry L.

2016-01-01

Background Recent evidence suggests that living kidney donors are at an increased risk of end-stage renal disease. However, predicting which donors will have renal dysfunction remains challenging, particularly among those with no clinical evidence of disease at the time of donation. Although renal biopsies are not routinely performed as part of the donor evaluation process, they may yield valuable information that improves the ability to predict renal function in donors. Methods We used implantation protocol biopsies to evaluate the association between histological abnormalities in the donated kidney and postdonation renal function (estimated glomerular filtration rate, eGFR) of the remaining kidney in living kidney donors. Longitudinal analysis using mixed-effects linear regression was used to account for multiple eGFR measures per donor. Results Among 310 donors between 1997 and 2012, median (IQR) follow-up was 6.2 (2.5–8.7; maximum 14.0) years. In this cohort, the overall prevalence of histological abnormalities was 65.8% (19.7% abnormal glomerulosclerosis, 23.9% abnormal interstitial fibrosis and tubular atrophy (IFTA), 4.8% abnormal mesangial matrix increase, 32.0% abnormal arteriolar hyalinosis, and 32.9% abnormal vascular intimal thickening). IFTA was associated with a 5-mL/min/1.73m2 decrease of postdonation eGFR after adjusting for donor age at donation, sex, race, preoperative systolic blood pressure, preoperative eGFR, and time since donation (p<0.01). Conclusions In this single-center study, among healthy individuals cleared for living donation, IFTA was associated with decreased postdonation eGFR, while no other subclinical histological abnormalities provided additional information. PMID:27152920

Substantial variation in the acceptance of medically complex live kidney donors across US renal transplant centers

PubMed Central

Reese, PP; Feldman, HI; McBride, MA; Anderson, K; Asch, DA; Bloom, RD

2008-01-01

Concern exists about accepting live kidney donation from “medically complex donors” -those with risk factors for future kidney disease. This study’s aim was to examine variation in complex kidney donor use across United States (US) transplant centers. We conducted a retrospective cohort study of live kidney donors using Organ Procurement and Transplantation Network data. Donors with hypertension, obesity, or estimated glomerular filtration rate (eGFR) <60 ml/minute/1.73m2 were considered medically complex. Among 9319 donors, 2254 (24.2%) were complex: 1194 (12.8%) were obese, 956 (10.3%) hypertensive, and 392 (4.2%) had low eGFR. The mean proportion of medically complex donors at a center was 24% (range 0 – 65%.) In multivariate analysis, donor characteristics associated with medical complexity included spousal relationship to the recipient (OR 1.29, CI 1.06-1.56, p<0.01), low education (OR 1.19, CI 1.04-1.37, p=0.01), older age (OR 1.01 per year, CI 1.01-1.02, p<0.01), and non-US citizenship (OR 0.70, CI 0.51-0.97, p=0.01). Renal transplant centers with the highest transplant volume (OR 1.26, CI 1.02-1.57, p=0.03), and with a higher proportion of (living donation)/(all kidney transplants) (OR 1.97, CI 1.23-3.16, p<0.01) were more likely to use medically complex donors. Though controversial, the use of medically complex donors is widespread and varies widely across centers. PMID:18727695

Origins of low resistivity and Ge donor level in Ge ion-implanted ZnO bulk single crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamioka, K.; Oga, T.; Izawa, Y.

2013-12-04

The energy level of Ge in Ge-ion implanted ZnO single crystals is studied by Hall-effect and photoluminescence (PL) methods. The variations in resistivity from ∼10{sup 3} Ωcm for un-implanted samples to ∼10{sup −2} Ωcm for as-implanted ones are observed. The resistivity is further decreased to ∼10{sup −3} Ωcm by annealing. The origins of the low resistivity are attributed to both the zinc interstitial (Zn{sub i}) related defects and the electrical activated Ge donor. An activation energy of Ge donors estimated from the temperature dependence of carrier concentration is 102 meV. In PL studies, the new peak at 372 nm (3.33more » eV) related to the Ge donor is observed in 1000 °C annealed samples.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohiyaddin, Fahd A.; Kalra, Rachpon; Laucht, Arne

The ability to transport quantum information across some distance can facilitate the design and operation of a quantum processor. One-dimensional spin chains provide a compact platform to realize scalable spin transport for a solid-state quantum computer. Here, we model odd-sized donor chains in silicon under a range of experimental nonidealities, including variability of donor position within the chain. We show that the tolerance against donor placement inaccuracies is greatly improved by operating the spin chain in a mode where the electrons are confined at the Si-SiO 2 interface. We then estimate the required time scales and exchange couplings, and themore » level of noise that can be tolerated to achieve high-fidelity transport. As a result, we also propose a protocol to calibrate and initialize the chain, thereby providing a complete guideline for realizing a functional donor chain and utilizing it for spin transport.« less

Direct and reverse pollen-mediated gene flow between GM rice and red rice weed

PubMed Central

Serrat, X.; Esteban, R.; Peñas, G.; Català, M. M.; Melé, E.; Messeguer, J.

2013-01-01

Potential risks of genetically modified (GM) crops must be identified before their commercialization, as happens with all new technologies. One of the major concerns is the proper risk assessment of adventitious presence of transgenic material in rice fields due to cross-pollination. Several studies have been conducted in order to quantify pollen-mediated gene flow from transgenic rice (Oryza sativa) to both conventional rice and red rice weed (O. sativa f. spontanea) under field conditions. Some of these studies reported GM pollen-donor rice transferring GM traits to red rice. However, gene flow also occurs in the opposite direction, in a phenomenon that we have called reverse gene flow, resulting in transgenic seeds that have incorporated the traits of wild red rice. We quantified reverse gene flow using material from two field trials. A molecular analysis based on amplified fragment length polymorphisms was carried out, being complemented with a phenotypic identification of red rice traits. In both field trials, the reverse gene flow detected was greater than the direct gene flow. The rate of direct gene flow varied according to the relative proportions of the donor (GM rice) and receptor (red rice) plants and was influenced by wind direction. The ecological impact of reverse gene flow is limited in comparison with that of direct gene flow because non-shattered and non-dormant seeds would be obtained in the first generation. Hybrid seed would remain in the spike and therefore most of it would be removed during harvesting. Nevertheless, this phenomenon must be considered in fields used for elite seed production and in developing countries where farmers often keep some seed for planting the following year. In these cases, there is a higher risk of GM red rice weed infestation increasing from year to year and therefore a proper monitoring plan needs to be established.

Dynamical photo-induced electronic properties of molecular junctions

NASA Astrophysics Data System (ADS)

Beltako, K.; Michelini, F.; Cavassilas, N.; Raymond, L.

2018-03-01

Nanoscale molecular-electronic devices and machines are emerging as promising functional elements, naturally flexible and efficient, for next-generation technologies. A deeper understanding of carrier dynamics in molecular junctions is expected to benefit many fields of nanoelectronics and power devices. We determine time-resolved charge current flowing at the donor-acceptor interface in molecular junctions connected to metallic electrodes by means of quantum transport simulations. The current is induced by the interaction of the donor with a Gaussian-shape femtosecond laser pulse. Effects of the molecular internal coupling, metal-molecule tunneling, and light-donor coupling on photocurrent are discussed. We then define the time-resolved local density of states which is proposed as an efficient tool to describe the absorbing molecule in contact with metallic electrodes. Non-equilibrium reorganization of hybridized molecular orbitals through the light-donor interaction gives rise to two phenomena: the dynamical Rabi shift and the appearance of Floquet-like states. Such insights into the dynamical photoelectronic structure of molecules are of strong interest for ultrafast spectroscopy and open avenues toward the possibility of analyzing and controlling the internal properties of quantum nanodevices with pump-push photocurrent spectroscopy.

Long-term Persistence of Innate Lymphoid Cells in the Gut After Intestinal Transplantation.

PubMed

Weiner, Joshua; Zuber, Julien; Shonts, Brittany; Yang, Suxiao; Fu, Jianing; Martinez, Mercedes; Farber, Donna L; Kato, Tomoaki; Sykes, Megan

2017-10-01

Little is known about innate lymphoid cell (ILC) populations in the human gut, and the turnover of these cells and their subsets after transplantation has not been described. Intestinal samples were taken from 4 isolated intestine and 3 multivisceral transplant recipients at the time of any operative resection, such as stoma closure or revision. ILCs were isolated and analyzed by flow cytometry. The target population was defined as being negative for lineage markers and double-positive for CD45/CD127. Cells were further stained to define ILC subsets and a donor-specific or recipient-specific HLA marker to analyze chimerism. Donor-derived ILCs were found to persist greater than 8 years after transplantation. Additionally, the percentage of cells thought to be lymphoid tissue inducer cells among donor ILCs was far higher than that among recipient ILCs. Our findings demonstrate that donor-derived ILCs persist long-term after transplantation and support the notion that human lymphoid tissue inducer cells may form in the fetus and persist throughout life, as hypothesized in rodents. Correlation between chimerism and rejection, graft failure, and patient survival requires further study.

Effect of increased pressure during pulsatile pump perfusion of deceased donor kidneys in transplantation.

PubMed

Patel, S K; Pankewycz, O G; Weber-Shrikant, E; Zachariah, M; Kohli, R; Nader, N D; Laftavi, M R

2012-09-01

Pulsatile pump perfusion of potential kidneys for transplantation is known to decrease the rate of delayed graft function (DGF) and improve their 1-year survival. Flow and resistance parameters are often used to determine the suitability of kidneys for transplantation. Kidneys with low flow rates are often subjected to higher pressures to improve flow. This study evaluated the effect of higher pump pressures on posttransplant renal function. We performed a retrospective analysis of 73 deceased donor kidneys preserved using pump perfusion (LifePort) at our center between May 2006 and September 2009. We calculated the mean pump pressure (MP) for the duration of perfusion of each kidney, using systolic pressure (SP) and diastolic pressure (DP) readings with the following formula: (MP = DP + 1/3 (SP - DP). The kidneys were divided into a low (LP; n = 49) and a high-pressure group (HP; n = 24) based on a MP cutoff value of 23 mm Hg. The two groups were then compared for differences in perfusion dynamics and primary endpoints including DGF and 1-year graft survival. Statistical analysis was performed using paired Student t test and chi-square analysis. The two groups were comparable for donor age, extended criteria, sensitization, and cold ischemic times. They differed significantly in higher initial (0.65 ± 0.4 versus 0.4 ± 0.2, P = .01), average (0.25 ± 0.08 versus 0.18 ± 0.06, P = .0006), and terminal resistance (0.21 ± 0.07 versus 0.17 ± 0.06, P = .008) of HP versus LP kidneys. Flow rates were comparable between the two groups. DGF was higher in HP kidneys (75% versus 40%, P = .006) with similar 1-year graft survival (87.5% versus 89%, P = .7). Perfusate flow through a kidney can be improved by increasing pressure settings to overcome elevated resistance. This maneuver was not associated with a lower rate of DGF after transplantation. One-year graft survival remained unaffected. Copyright © 2012 Elsevier Inc. All rights reserved.

Effect of blood donor characteristics on transfusion outcomes: a protocol for systematic review and meta-analysis.

PubMed

Chassé, Michaël; English, Shane W; McIntyre, Lauralyn; Knoll, Greg; Shehata, Nadine; Forster, Alan; Wilson, Kumanan; van Walraven, Carl; Tinmouth, Alan; Fergusson, Dean A

2014-03-20

Optimal selection of blood donors is of paramount importance in ensuring the safety of blood products. The current selection process is concerned principally with the safety of the blood donor and the safety of the patient that receives the blood. Recent evidence suggests that the characteristics of the donor may affect transfusion outcomes for the recipient. We will conduct a systematic review of the association between major blood donor characteristics and red blood cell (RBC) transfusion outcomes. The primary objective is to assess the association of blood donor characteristics and the risk of adverse short-term and long-term clinical outcomes after RBC transfusion. We will search MEDLINE, EMBASE, Cochrane Central databases, as well as perform manual searches of top transfusion medical journals for prospective and retrospective studies. Study characteristics will be reported and the methodological quality of studies will be assessed. When appropriate, we will provide pooled odds ratio with 95% confidence intervals of the effect estimates, study clinical heterogeneity using pre-defined sensitivity and subgroup analyses, and study statistical heterogeneity using the I2 test. The results of this systematic review will provide an evidence base regarding the potential clinical effects of donor characteristics on transfusion recipients to better guide policy and clinical practice. The evidence gathered from this review will also identify strengths and weaknesses of published studies regarding donor characteristics and transfusion outcomes and will identify knowledge gaps to inform future research in this field of transfusion medicine. PROSPERO Registration Number: CRD42013006726.

Blood donors’ physical characteristics are associated with pre- and post-donation symptoms - Donor InSight

PubMed Central

van den Hurk, Katja; Peffer, Karlijn; Habets, Karin; Atsma, Femke; Pasker-de Jong, Pieternel C.M.; van Noord, Paulus A.H.; Veldhuizen, Ingrid J.T.; de Kort, Wim L.A.M.

2017-01-01

Background Observational data suggest that some donors might benefit from donating while others may be harmed. The aim of this study was to investigate the prevalence and potential, routinely measured, determinants of pre- and post-donation symptoms. Materials and methods In Donor InSight, questionnaire data from 23,064 whole blood donors (53% female) were linked to routinely measured data on donors’ physical characteristics (haemoglobin, blood pressure, body mass index and estimated blood volume) from the Dutch donor database. Absolute and relative associations between donors’ physical donor and the presence of pre- and post-donation symptoms were studied using multivariable logistic regression. Results Pre-donation symptoms (lack of energy, headaches) were reported by 3% of men and 3% of women. Five percent of men and 4% of women reported positive post-donation symptoms (feeling fit, fewer headaches). Negative symptoms (fatigue, dizziness) were more common, occurring in 8% of men and 19% of women. All the studied donors’ physical characteristics were positively associated with pre- and positive post-donation symptoms and negatively associated with negative symptoms. Body mass index was most consistently and independently associated with symptoms. Discussion Donors’ physical characteristics, in particular body mass index, were consistently associated with pre- and post-donation symptoms. This indicates that subgroups of donors more and less tolerant to donation might be identifiable using routinely measured data. Further research is warranted to study underlying mechanisms and potential strategies to predict and prevent donor reactions. PMID:27416579

Single-particle fusion of influenza viruses reveals complex interactions with target membranes

NASA Astrophysics Data System (ADS)

van der Borg, Guus; Braddock, Scarlett; Blijleven, Jelle S.; van Oijen, Antoine M.; Roos, Wouter H.

2018-05-01

The first step in infection of influenza A virus is contact with the host cell membrane, with which it later fuses. The composition of the target bilayer exerts a complex influence on both fusion efficiency and time. Here, an in vitro, single-particle approach is used to study this effect. Using total internal reflection fluorescence (TIRF) microscopy and a microfluidic flow cell, the hemifusion of single virions is visualized. Hemifusion efficiency and kinetics are studied while altering target bilayer cholesterol content and sialic-acid donor. Cholesterol ratios tested were 0%, 10%, 20%, and 40%. Sialic-acid donors GD1a and GYPA were used. Both cholesterol ratio and sialic-acid donors proved to have a significant effect on hemifusion efficiency. Furthermore, comparison between GD1a and GYPA conditions shows that the cholesterol dependence of the hemifusion time is severely affected by the sialic-acid donor. Only GD1a shows a clear increasing trend in hemifusion efficiency and time with increasing cholesterol concentration of the target bilayer with maximum rates for GD1A and 40% cholesterol. Overall our results show that sialic acid donor and target bilayer composition should be carefully chosen, depending on the desired hemifusion time and efficiency in the experiment.

42 CFR 121.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... composite allograft (defined in this section). Blood vessels recovered from an organ donor during the... composite allograft means a body part: (1) That is vascularized and requires blood flow by surgical connection of blood vessels to function after transplantation; (2) Containing multiple tissue types; (3...

42 CFR 121.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... composite allograft (defined in this section). Blood vessels recovered from an organ donor during the... composite allograft means a body part: (1) That is vascularized and requires blood flow by surgical connection of blood vessels to function after transplantation; (2) Containing multiple tissue types; (3...

Lung physiology during ECS resuscitation of DCD donors followed by in situ assessment of lung function.

PubMed

Reoma, Junewai L; Rojas, Alvaro; Krause, Eric M; Obeid, Nabeel R; Lafayette, Nathan G; Pohlmann, Joshua R; Padiyar, Niru P; Punch, Jeffery D; Cook, Keith E; Bartlett, Robert H

2009-01-01

Extracorporeal cardiopulmonary support (ECS) of donors after cardiac death (DCD) has been shown to improve abdominal organs for transplantation. This study assesses whether pulmonary congestion occurs during ECS with the heart arrested and describes an in vivo method to assess if lungs are suitable for transplantation from DCD donors after ECS resuscitation. Cardiac arrest was induced in 30 kg pigs, followed by 10 min of warm ischemia. Cannulae were placed into the right atrium (RA) and iliac artery, and veno-arterial ECS was initiated for 90 min with lungs inflated, group 1 (n = 5) or deflated, group 2 (n = 3). Left atrial pressures were measured as a marker for pulmonary congestion. After 90 min of ECS, lung function was evaluated. Cannulae were placed into the pulmonary artery (PA) and left ventricle (LV). A second pump was included, and ECS was converted to a bi-ventricular (bi-VAD) system. The RVAD drained from the RA and pumped into the PA, and the LVAD drained the LV and pumped into the iliac. This brought the lungs back into circulation for a 1-hr assessment period. The oxygenator was turned off, and ventilation was restarted. Flows, blood gases, PA and left atrial pressures, and compliance were recorded. In both the groups, LA pressure was <15 mm Hg during ECS. During the lung assessment period, PA flows were 1.4-2.2 L/min. PO2 was >300 mm Hg, with normal PCO2. Extracorporeal cardiopulmonary support resuscitation of DCD donors is feasible and allows for assessment of function before procurement. Extracorporeal cardiopulmonary support does not cause pulmonary congestion, and the lungs retain adequate function for transplantation. Compliance correlated with lung function.

LUNG PHYSIOLOGY DURING ECS RESUSCITATION OF DCD DONORS FOLLOWED BY IN-SITU ASSESSMENT OF LUNG FUNCTION

PubMed Central

Reoma, Junewai L.; Rojas, Alvaro; Krause, Eric M.; Obeid, Nabeel R.; Lafayette, Nathan G.; Pohlmann, Joshua R.; Padiyar, Niru P.; Punch, Jeffery D; Cook, Keith E.; Bartlett, Robert H

2009-01-01

Extracorporeal cardiopulmonary support(ECS) of donors following cardiac death(DCD) has been shown to improve abdominal organs for transplantation. This study assesses whether pulmonary congestion occurs during ECS with the heart arrested and describes an in-vivo method to assess if lungs are suitable for transplantation from DCD donors following ECS resuscitation. Cardiac arrest was induced in 30 kg pigs, followed by 10min. of warm ischemia. Cannulas were placed into right atrium (RA) and iliac artery, and veno-arterial ECS was initiated for 90min with lungs inflated, Group 1 (n=5) or deflated Group 2 (n=3). Left atrial pressures were measured as a marker for pulmonary congestion. After 90 min of ECS, lung function was evaluated. Cannulae were placed into the pulmonary artery (PA) and left ventricle (LV). A second pump was included, and ECS was converted to a bi-VAD system. The RVAD drained from the RA and pumped into the PA, and the LVAD drained the LV and pumped into the iliac. This brought the lungs back into circulation for a 1hr assessment period. The oxygenator was turned off, and ventilation restarted. Flows, blood gases, pulmonary artery and left atrial pressures, and compliance were recorded. In both groups: LA pressure was <15mmHg during ECS. During the lung assessment period, PA flows were 1.4−2.2 liter/min. PO2 was >300mmHg, with normal PCO2. ECS resuscitation of DCD donors is feasible and allows for assessment of function prior to procurement. ECS does not cause pulmonary congestion, and lungs retain adequate function for transplantation. Compliance correlated with lung function. PMID:19506464

[Prior harvesting and cryopreservation of peripheral blood stem cells from related donors: current situations in Japan].

PubMed

Kobayashi, Takeshi; Ohashi, Kazuteru; Haraguchi, Kyoko; Okuyama, Yoshiki; Hino, Masayuki; Tanaka, Junji; Ueda, Yasunori; Nishida, Tetsuya; Atsuta, Yoshiko; Takanashi, Minoko; Iida, Minako; Muroi, Kazuo; Yabe, Hiromasa; Miyamura, Koichi

Although peripheral blood stem cell (PBSC) transplantations in an unrelated transplant setting have been performed since 2010, prior harvesting and cryopreservation of PBSCs from unrelated donors has not been approved in Japan. There are no restrictions with regard to related donors. Therefore, in April 2015, we conducted a nationwide survey and obtained written answers from 123 transplant hospitals throughout Japan. Our survey revealed that as much as 81.3% of transplant hospitals routinely perform prior harvesting and cryopreservation of PBSCs from related donors and that both cell processing and quality management of cryopreserved products have been appropriately conducted in line with domestic guidelines, although post-thaw quality control and storage period setting require further improvements. Moreover, informed consent obtained from both patients and donors with regard to cryopreservation of PBSCs was not always sufficient in some hospitals. We found that the average number of unused or discarded cryopreserved PBSCs is 1.09 per hospital, and the overall nonuse or discard rates of cryopreserved PBSCs were estimated to be as low as 2.67%.

Donor states in a semimagnetic Cd1 -xinMnxin Te /Cd1 -xoutMnxout Te Double Quantum Well

NASA Astrophysics Data System (ADS)

Kalpana, Panneer Selvam; Nithiananthi, Perumal; Jayakumar, Kalyanasundaram

2017-02-01

The theoretical investigation has been carried out on the binding energy of donor associated with the electrons confined in a Cd1 -xinMnxin Te /Cd1 -xoutMnxout Te Double Quantum Well (DQW) as a function of central barrier width for various well dimensions and impurity locations in the barrier and the well. The magnetic field can act as a tool to continuously change the interwell coupling inside this DQW systems and its effect on donor binding has also been studied. Moreover, the polaronic corrections, which is due to the strong exchange interaction between the magnetic moment of Mn2+ ion and the spin of the confined carrier, to the binding energy of the hydrogenic donor impurity has also been estimated with and without the application of magnetic field. The binding energy of the donor impurity is determined by solving the Schrodinger equation variationally in the effective mass approximation and the effect due to Bound Magnetic Polaron (BMP) is included using mean field theory with the modified Brillouin function. The results are reported and discussed.

Reduced-intensity conditioning allogeneic SCT as salvage treatment for relapsed multiple myeloma.

PubMed

de Lavallade, H; El-Cheikh, J; Faucher, C; Fürst, S; Stoppa, A-M; Coso, D; Bouabdallah, R; Chabannon, C; Gastaut, J-A; Blaise, D; Mohty, M

2008-06-01

The aim of this retrospective analysis was to assess the benefit of reduced-intensity conditioning allo SCT (RIC allo-SCT) in a cohort of 32 relapsed multiple myeloma (MM) patients. A total of 19 patients had an HLA-identical sibling donor ('donor' group), while 13 patients had no donor ('no-donor' group). There were no significant differences between these two groups as for prognosis risk factors. Eighteen patients from the 'donor' group could actually proceed to RIC allo-SCT. With a median follow-up of 36 (range, 21-60) months, six patients died from transplant-related toxicity (cumulative incidence, 33% (95% CI, 11-55%)). Only 4 patients from the 18 transplanted patients (22%; 95% CI, 7-48%) progressed after RIC allo-SCT, as compared to 12 (86%; 95% CI, 56-98%; P=0.0003) among the nontransplanted patients. In an 'intention-to-treat' analysis, the Kaplan-Meier estimate of PFS was significantly higher in the 'donor' group as compared to the 'no-donor' group (P=0.01; 46 versus 8% at 3 years). There was no difference in terms of overall survival. However, in multivariate analysis, actual performance of RIC allo-SCT was associated with better PFS (relative risk, 0.35; 95% CI, 0.15-0.82; P=0.01). These data suggest a potential benefit for RIC allo-SCT in the management of relapsed MM warranting further prospective investigations.

Donating blood: a meta-analytic review of self-reported motivators and deterrents.

PubMed

Bednall, Timothy C; Bove, Liliana L

2011-10-01

Although research on blood donor motivation abounds, most studies have typically focused on small sets of variables, used different terminology to label equivalent constructs, and have not attempted to generalize findings beyond their individual settings. The current study sought to synthesize past findings into a unified taxonomy of blood donation drivers and deterrents and to estimate the prevalence of each factor across the worldwide population of donors and eligible nondonors. Primary studies were collected, and cross-validated categories of donation motivators and deterrents were developed. Proportions of first-time, repeat, lapsed, apheresis, and eligible nondonors endorsing each category were calculated. In terms of motivators, first-time and repeat donors most frequently cited convenience, prosocial motivation, and personal values; apheresis donors similarly cited the latter 2 motivators and money. Conversely, lapsed donors more often cited collection agency reputation, perceived need for donation, and marketing communication as motivators. In terms of deterrents, both donors and nondonors most frequently referred to low self-efficacy to donate, low involvement, inconvenience, absence of marketing communication, ineffective incentives, lack of knowledge about donating, negative service experiences, and fear. The integration of past findings has yielded a comprehensive taxonomy of factors influencing blood donation and has provided insight into the prevalence of each factor across multiple stages of donors' careers. Implications for collection agencies are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

Longitudinal Assessment of Renal Perfusion and Oxygenation in Transplant Donor-Recipient Pairs Using Arterial Spin Labeling and Blood Oxygen Level-Dependent Magnetic Resonance Imaging.

PubMed

Niles, David J; Artz, Nathan S; Djamali, Arjang; Sadowski, Elizabeth A; Grist, Thomas M; Fain, Sean B

2016-02-01

The aims of this study were to assess renal function in kidney transplant recipients and their respective donors over 2 years using arterial spin labeling (ASL) and blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) and to prospectively evaluate the effect of losartan on functional MRI measures in recipients. The study included 15 matched pairs of renal transplant donors and recipients. Arterial spin labeling and BOLD MRI of the kidneys were performed on donors before transplant surgery (baseline) and on both donors and recipients at 3 months, 1 year, and 2 years after transplant. After 3 months, 7 of the 15 recipients were prescribed 25 to 50 mg/d losartan for the remainder of the study. A linear mixed-effects model was used to evaluate perfusion, R2*, estimated glomerular filtration rate, and fractional excretion of sodium for changes across time or associated with losartan treatment. In donors, cortical perfusion in the remaining kidney decreased by 50 ± 19 mL/min per 100 g (11.8%) between baseline and 2 years (P < 0.05), while cortical R2* declined modestly by 0.7 ± 0.3 s-1 (5.6%; P < 0.05). In transplanted kidneys, cortical perfusion decreased markedly by 141 ± 21 mL/min per 100 g (34.2%) between baseline and 2 years (P < 0.001), while medullary R2* declined by 1.5 ± 0.8 s-1 (8.3%; P = 0.06). Single-kidney estimated glomerular filtration rate increased between baseline and 2 years by 17.7 ± 2.7 mL/min per 1.73 m (40.3%; P < 0.0001) in donors and to 14.6 ± 4.3 mL/min per 1.73 m (33.3%; P < 0.01) in recipients. Cortical perfusion at 1 and 2 years in recipients receiving 25 to 50 mg/d losartan was 62 ± 24 mL/min per 100 g higher than recipients not receiving the drug (P < 0.05). No significant effects of losartan were observed for any other markers of renal function. The results suggest an important role for noninvasive functional monitoring with ASL and BOLD MRI in kidney transplant recipients and donors, and they indicate a potentially beneficial effect of losartan in recipients.

Genetic history of the population of Corsica (western Mediterranean) as inferred from autosomal STR analysis.

PubMed

Tofanelli, Sergio; Taglioli, Luca; Varesi, Laurent; Paoli, Giorgio

2004-04-01

To genetically reconstruct the demographic history of the human population of Corsica (western Mediterranean), we analyzed the variability at eight autosomal STR loci (FES, VWA, CSF1PO, TH01, F13A1, TPOX, CD4, and D3S1358) in a sample of 179 native blood donors from 4 out of the 5 administrative districts. The main line of genetic discontinuity inferred from the spatial distribution of STR variability overlapped the linguistic and geographic boundaries. In the innermost areas (Corte district) several estimators had larger stochastic effects on allele frequencies. Genetic distance measures underlying different evolutionary models all pointed to a higher variability within Corsicans than within the rest of the Mediterranean reference populations. All Corsican subsamples showed the highest distance with a pooled sample from central Sardinia, thus making recent gene flow between the two neighboring islands unlikely. Hierarchical AMOVA and distance-based multivariate genetic spaces stressed the closeness of Tuscan and Corsican frequency distributions, which could reflect peopling events with different time depths. Anyway, estimated separation times well support the linguistic hypothesis that Neolithic/Chalcolithic events have been far more important than Paleolithic or historical processes in the shaping of present Corsican variability.

Measuring Ambiguity in HLA Typing Methods

PubMed Central

Madbouly, Abeer; Freeman, John; Maiers, Martin

2012-01-01

In hematopoietic stem cell transplantation, donor selection is based primarily on matching donor and patient HLA genes. These genes are highly polymorphic and their typing can result in exact allele assignment at each gene (the resolution at which patients and donors are matched), but it can also result in a set of ambiguous assignments, depending on the typing methodology used. To facilitate rapid identification of matched donors, registries employ statistical algorithms to infer HLA alleles from ambiguous genotypes. Linkage disequilibrium information encapsulated in haplotype frequencies is used to facilitate prediction of the most likely haplotype assignment. An HLA typing with less ambiguity produces fewer high-probability haplotypes and a more reliable prediction. We estimated ambiguity for several HLA typing methods across four continental populations using an information theory-based measure, Shannon's entropy. We used allele and haplotype frequencies to calculate entropy for different sets of 1,000 subjects with simulated HLA typing. Using allele frequencies we calculated an average entropy in Caucasians of 1.65 for serology, 1.06 for allele family level, 0.49 for a 2002-era SSO kit, and 0.076 for single-pass SBT. When using haplotype frequencies in entropy calculations, we found average entropies of 0.72 for serology, 0.73 for allele family level, 0.05 for SSO, and 0.002 for single-pass SBT. Application of haplotype frequencies further reduces HLA typing ambiguity. We also estimated expected confirmatory typing mismatch rates for simulated subjects. In a hypothetical registry with all donors typed using the same method, the entropy values based on haplotype frequencies correspond to confirmatory typing mismatch rates of 1.31% for SSO versus only 0.08% for SBT. Intermediate-resolution single-pass SBT contains the least ambiguity of the methods we evaluated and therefore the most certainty in allele prediction. The presented measure objectively evaluates HLA typing methods and can help define acceptable HLA typing for donor recruitment. PMID:22952712

Live Donor Renal Anatomic Asymmetry and Posttransplant Renal Function.

PubMed

Tanriover, Bekir; Fernandez, Sonalis; Campenot, Eric S; Newhouse, Jeffrey H; Oyfe, Irina; Mohan, Prince; Sandikci, Burhaneddin; Radhakrishnan, Jai; Wexler, Jennifer J; Carroll, Maureen A; Sharif, Sairah; Cohen, David J; Ratner, Lloyd E; Hardy, Mark A

2015-08-01

Relationship between live donor renal anatomic asymmetry and posttransplant recipient function has not been studied extensively. We analyzed 96 live kidney donors, who had anatomical asymmetry (>10% renal length and/or volume difference calculated from computerized tomography angiograms) and their matching recipients. Split function differences (SFD) were quantified with technetium-dimercaptosuccinic acid renography. Implantation biopsies at time 0 were semiquantitatively scored. A comprehensive model using donor renal volume adjusted to recipient weight (Vol/Wgt), SFD, and biopsy score was used to predict recipient estimated glomerular filtration rate (eGFR) at 1 year. Primary analysis consisted of a logistic regression model of outcome (odds of developing eGFR>60 mL/min/1.73 m(2) at 1 year), a linear regression model of outcome (predicting recipient eGFR at one-year, using the chronic kidney disease-epidemiology collaboration formula), and a Monte Carlo simulation based on the linear regression model (N=10,000 iterations). In the study cohort, the mean Vol/Wgt and eGFR at 1 year were 2.04 mL/kg and 60.4 mL/min/1.73 m(2), respectively. Volume and split ratios between 2 donor kidneys were strongly correlated (r = 0.79, P < 0.001). The biopsy scores among SFD categories (<5%, 5%-10%, >10%) were not different (P = 0.190). On multivariate models, only Vol/Wgt was significantly associated with higher odds of having eGFR > 60 mL/min/1.73 m (odds ratio, 8.94, 95% CI 2.47-32.25, P = 0.001) and had a strong discriminatory power in predicting the risk of eGFR less than 60 mL/min/1.73 m(2) at 1 year [receiver operating curve (ROC curve), 0.78, 95% CI, 0.68-0.89]. In the presence of donor renal anatomic asymmetry, Vol/Wgt appears to be a major determinant of recipient renal function at 1 year after transplantation. Renography can be replaced with CT volume calculation in estimating split renal function.

Live Donor Renal Anatomic Asymmetry and Post-Transplant Renal Function

PubMed Central

Tanriover, Bekir; Fernandez, Sonalis; Campenot, Eric S.; Newhouse, Jeffrey H.; Oyfe, Irina; Mohan, Prince; Sandikci, Burhaneddin; Radhakrishnan, Jai; Wexler, Jennifer J.; Carroll, Maureen A.; Sharif, Sairah; Cohen, David J.; Ratner, Lloyd E.; Hardy, Mark A.

2014-01-01

Background Relationship between live donor renal anatomic asymmetry and post-transplant recipient function has not been studied extensively. Methods We analyzed 96 live-kidney donors, who had anatomical asymmetry (>10% renal length and/or volume difference calculated from CT angiograms) and their matching recipients. Split function differences (SFD) were quantified with 99mTc-DMSA renography. Implantation biopsies at time-zero were semi-quantitatively scored. A comprehensive model utilizing donor renal volume adjusted to recipient weight (Vol/Wgt), SFD, and biopsy score was used to predict recipient estimated glomerular filtration rate (eGFR) at one-year. Primary analysis consisted of a logistic regression model of outcome (odds of developing eGFR>60ml/min/1.73 m2 at one-year), a linear regression model of outcome (predicting recipient eGFR at one-year, using the CKD-EPI formula), and a Monte Carlo simulation based on the linear regression model (N=10,000 iterations). Results In the study cohort, the mean Vol/Wgt and eGFR at one-year were 2.04 ml/kg and 60.4 ml/min/1.73m2, respectively. Volume and split ratios between two donor kidneys were strongly correlated (r=0.79, p-value<0.001). The biopsy scores among SFD categories (<5%, 5–10%, >10%) were not different (p=0.190). On multivariate models, only Vol/Wgt was significantly associated with higher odds of having eGFR>60ml/min/1.73 m2 (OR=8.94, 95% CI 2.47–32.25, p=0.001) and had a strong discriminatory power in predicting the risk of eGFR<60ml/min/1.73m2 at one-year (ROC curve=0.78, 95% CI 0.68–0.89). Conclusion In the presence of donor renal anatomic asymmetry, Vol/Wgt appears to be a major determinant of recipient renal function at one-year post-transplantation. Renography can be replaced with CT volume calculation in estimating split renal function. PMID:25719258

Similar 5-Year Estimated Glomerular Filtration Rate Between Kidney Transplants From Uncontrolled and Controlled Donors After Circulatory Death—A Dutch Cohort Study

PubMed Central

Peters-Sengers, Hessel; Homan van der Heide, Jaap J.; Heemskerk, Martin B. A.; ten Berge, Ineke J. M.; Ultee, Fred C. W.; Idu, Mirza M.; Betjes, Michiel G. H.; van Zuilen, Arjan D.; Christiaans, Maarten H. L.; Hilbrands, Luuk H.; de Vries, Aiko P. J.; Nurmohamed, Azam S.; Berger, Stefan P.; Bemelman, Frederike J.

2017-01-01

Background Organ shortage persists despite a high rate of donation after circulatory death (DCD) in the Netherlands. The median waiting time for a deceased donor kidney in 2013 was 3.5 years. Most DCD kidneys are from controlled DCD (cDCD; Maastricht category III). Experience with uncontrolled donors after cardiac death (uDCD), that is, donors with an unexpected and irreversible cardiac arrest (Maastricht categories I and II), is increasing; and its effect on transplant outcomes needs evaluation. Methods We used the Dutch Organ Transplantation Registry to include recipients (≥18 years old) from all Dutch centers who received transplants from 2002 to 2012 with a first DCD kidney. We compared transplant outcome in uDCD (n = 97) and cDCD (n = 1441). Results Primary nonfunction in uDCD was higher than in the cDCD (19.6% vs 9.6%, P < 0.001, respectively). Delayed graft function was also higher in uDCD than in cDCD, but not significantly (73.7% vs 63.3%, P = .074, respectively). If censored for primary nonfunction, estimated glomerular filtration rates after 1 year and 5 years were comparable between uDCD and cDCD (1 year: uDCD, 44.3 (23.4) mL/min/m2 and cDCD, 45.8 (24.1) mL/min/m2; P = 0.621; 5 years: uDCD, 49.1 (25.6) mL/min/m2 and cDCD, 47.7 (21.7) mL/min/m2; P = 0.686). The differences in primary nonfunction between kidneys from uDCD and cDCD were explained by differences in the first warm ischemic period, cold ischemic time, and donor age. Conclusions We conclude that uDCD kidneys have potential for excellent function and can constitute a valuable extension of the donor pool. However, further efforts are necessary to address the high rate of primary nonfunction. PMID:27257998

The NO donor sodium nitroprusside: evaluation of skeletal muscle vascular and metabolic dysfunction

PubMed Central

Hirai, Daniel M.; Copp, Steven W.; Ferguson, Scott K.; Holdsworth, Clark T.; Musch, Timothy I.; Poole, David C.

2012-01-01

The nitric oxide (NO) donor sodium nitroprusside (SNP) may promote cyanide-induced toxicity and systemic and/or local responses approaching maximal vasodilation. The hypotheses were tested that SNP superfusion of the rat spinotrapezius muscle exerts 1) residual impairments in resting and contracting blood flow, oxygen utilization (V̇O2) and microvascular O2 pressure (PO2mv); and 2) marked hypotension and elevation in resting PO2mv. Two superfusion protocols were performed: 1) Krebs-Henseleit (control 1), SNP (300 µM; a dose used commonly in superfusion studies) and Krebs-Henseleit (control 2), in this order; 2) 300 and 1200 µM SNP in random order. Spinotrapezius muscle blood flow (radiolabeled microspheres), V̇O2 (Fick calculation) and PO2mv (phosphorescence quenching) were determined at rest and during electrically-induced (1 Hz) contractions. There were no differences in spinotrapezius blood flow, V̇O2 or PO2mv at rest and during contractions pre- and post-SNP condition (control 1 and control 2; p>0.05 for all). With regard to dosing, SNP produced a graded elevation in resting PO2mv (p<0.05) with a reduction in mean arterial pressure only at the higher concentration (p<0.05). Contrary to our hypothesis, skeletal muscle superfusion with the NO donor SNP (300 µM) improved microvascular oxygenation during the transition from rest to contractions (PO2mv kinetics) without precipitating residual impairment of muscle hemodynamic or metabolic control or compromising systemic hemodynamics. These data suggest that SNP superfusion (300 µM) constitutes a valid and important tool for assessing the functional roles of NO in resting and contracting skeletal muscle function without incurring residual alterations consistent with cyanide accumulation and poisoning. PMID:23174313

Donor funding health policy and systems research in low- and middle-income countries: how much, from where and to whom.

PubMed

Grépin, Karen Ann; Pinkstaff, Crossley Beth; Shroff, Zubin Cyrus; Ghaffar, Abdul

2017-08-31

The need for sufficient and reliable funding to support health policy and systems research (HPSR) in low- and middle-income countries (LMICs) has been widely recognised. Currently, most resources to support such activities come from traditional development assistance for health (DAH) donors; however, few studies have examined the levels, trends, sources and national recipients of such support - a gap this research seeks to address. Using OECD's Creditor Reporting System database, we classified donor funding commitments using a keyword analysis of the project-level descriptions of donor supported projects to estimate total funding available for HPSR-related activities annually from bilateral and multilateral donors, as well as the Bill and Melinda Gates Foundation, to LMICs over the period 2000-2014. Total commitments to HPSR-related activities have greatly increased since 2000, peaked in 2010, and have held steady since 2011. Over the entire study period (2000-2014), donors committed a total of $4 billion in funding for HPSR-related activities or an average of $266 million a year. Over the last 5 years (2010-2014), donors committed an average of $434 million a year to HPSR-related activities. Funding for HPSR is heavily concentrated, with more than 93% coming from just 10 donors and only represents approximately 2% of all donor funding for health and population projects. Countries in the sub-Saharan African region are the major recipients of HPSR funding. Funding for HPSR-related activities has generally increased over the study period; however, donor support to such activities represents only a small proportion of total DAH and has not grown in recent years. Donors should consider increasing the proportion of funds they allocate to support HPSR activities in order to further build the evidence base on how to build stronger health systems.

Dangerous universal donors: the reality of the Hemocentro in Belo Horizonte, Minas Gerais.

PubMed

Godin, Mariana Martins; Souza, Lucas de Oliveira; Schmidt, Luciana Cayres; Vieira, Lauro Mello; Diniz, Rejane Silva; Dusse, Luci Maria SantAna

2016-01-01

The term dangerous universal blood donor refers to potential agglutination of the erythrocytes of non-O recipients due to plasma of an O blood group donor, which contains high titers of anti-A and/or anti-B hemagglutinins. Thus, prior titration of anti-A and anti-B hemagglutinins is recommended to prevent transfusion reactions. The aim of this study was to estimate the frequency of dangerous universal donors in the blood bank of Belo Horizonte (Fundação Central de Imuno-Hematologia - Fundação Hemominas - Minas Gerais) by determining the titers of anti-A and anti-B hemagglutinins in O blood group donors. A total of 400 O blood group donors were randomly selected, from March 2014 to January 2015. The titers of anti-A and anti-B hemagglutinins (IgM and IgG classes) were obtained using the tube titration technique. Dangerous donors were those whose titers of anti-A or anti-B IgM were ≥128 and/or the titers of anti-A or anti-B IgG were ≥256. Donors were characterized according to gender, age and ethnicity. The hemagglutinins were characterized by specificity (anti-A and anti-B) and antibody class (IgG and IgM). Almost one-third (30.5%) of the O blood group donors were universal dangerous. The frequency among women was higher than that of men (p-value=0.019; odds ratio: 1.66; 95% confidence interval: 1.08-2.56) and among young donors (18-29 years old) it was higher than for donors between 49 and 59 years old (p-value=0.015; odds ratio: 3.05; 95% confidence interval: 1.22-7.69). There was no significant association between dangerous universal donors and ethnicity, agglutinin specificity or antibody class. Especially platelet concentrates obtained by apheresis (that contain a substantial volume of plasma), coming from dangerous universal donors should be transfused in isogroup recipients whenever possible in order to prevent the occurrence of transfusion reactions. Copyright © 2016 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved.

Towards a standardised informed consent procedure for live donor nephrectomy: the PRINCE (Process of Informed Consent Evaluation) project-study protocol for a nationwide prospective cohort study.

PubMed

Kortram, Kirsten; Spoon, Emerentia Q W; Ismail, Sohal Y; d'Ancona, Frank C H; Christiaans, Maarten H L; van Heurn, L W Ernest; Hofker, H Sijbrand; Hoksbergen, Arjan W J; Homan van der Heide, Jaap J; Idu, Mirza M; Looman, Caspar W N; Nurmohamed, S Azam; Ringers, Jan; Toorop, Raechel J; van de Wetering, Jacqueline; Ijzermans, Jan N M; Dor, Frank J M F

2016-04-01

Informed consent is mandatory for all (surgical) procedures, but it is even more important when it comes to living kidney donors undergoing surgery for the benefit of others. Donor education, leading to informed consent, needs to be carried out according to certain standards. Informed consent procedures for live donor nephrectomy vary per centre, and even per individual healthcare professional. The basis for a standardised, uniform surgical informed consent procedure for live donor nephrectomy can be created by assessing what information donors need to hear to prepare them for the operation and convalescence. The PRINCE (Process of Informed Consent Evaluation) project is a prospective, multicentre cohort study, to be carried out in all eight Dutch kidney transplant centres. Donor knowledge of the procedure and postoperative course will be evaluated by means of pop quizzes. A baseline cohort (prior to receiving any information from a member of the transplant team in one of the transplant centres) will be compared with a control group, the members of which receive the pop quiz on the day of admission for donor nephrectomy. Donor satisfaction will be evaluated for all donors who completed the admission pop-quiz. The primary end point is donor knowledge. In addition, those elements that have to be included in the standardised format informed consent procedure will be identified. Secondary end points are donor satisfaction, current informed consent practices in the different centres (eg, how many visits, which personnel, what kind of information is disclosed, in which format, etc) and correlation of donor knowledge with surgeons' estimation thereof. Approval for this study was obtained from the medical ethical committee of the Erasmus MC, University Medical Center, Rotterdam, on 18 February 2015. Secondary approval has been obtained from the local ethics committees in six participating centres. Approval in the last centre has been sought. Outcome will be published in a scientific journal. NTR5374; Pre-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Towards a standardised informed consent procedure for live donor nephrectomy: the PRINCE (Process of Informed Consent Evaluation) project—study protocol for a nationwide prospective cohort study

PubMed Central

Kortram, Kirsten; Spoon, Emerentia Q W; Ismail, Sohal Y; d'Ancona, Frank C H; Christiaans, Maarten H L; van Heurn, L W Ernest; Hofker, H Sijbrand; Hoksbergen, Arjan W J; Homan van der Heide, Jaap J; Idu, Mirza M; Looman, Caspar W N; Nurmohamed, S Azam; Ringers, Jan; Toorop, Raechel J; van de Wetering, Jacqueline; Ijzermans, Jan N M; Dor, Frank J M F

2016-01-01

Introduction Informed consent is mandatory for all (surgical) procedures, but it is even more important when it comes to living kidney donors undergoing surgery for the benefit of others. Donor education, leading to informed consent, needs to be carried out according to certain standards. Informed consent procedures for live donor nephrectomy vary per centre, and even per individual healthcare professional. The basis for a standardised, uniform surgical informed consent procedure for live donor nephrectomy can be created by assessing what information donors need to hear to prepare them for the operation and convalescence. Methods and analysis The PRINCE (Process of Informed Consent Evaluation) project is a prospective, multicentre cohort study, to be carried out in all eight Dutch kidney transplant centres. Donor knowledge of the procedure and postoperative course will be evaluated by means of pop quizzes. A baseline cohort (prior to receiving any information from a member of the transplant team in one of the transplant centres) will be compared with a control group, the members of which receive the pop quiz on the day of admission for donor nephrectomy. Donor satisfaction will be evaluated for all donors who completed the admission pop-quiz. The primary end point is donor knowledge. In addition, those elements that have to be included in the standardised format informed consent procedure will be identified. Secondary end points are donor satisfaction, current informed consent practices in the different centres (eg, how many visits, which personnel, what kind of information is disclosed, in which format, etc) and correlation of donor knowledge with surgeons' estimation thereof. Ethics and dissemination Approval for this study was obtained from the medical ethical committee of the Erasmus MC, University Medical Center, Rotterdam, on 18 February 2015. Secondary approval has been obtained from the local ethics committees in six participating centres. Approval in the last centre has been sought. Results Outcome will be published in a scientific journal. Trial registration number NTR5374; Pre-results. PMID:27036141

Platelet Counts in Insoluble Platelet-Rich Fibrin Clots: A Direct Method for Accurate Determination.

PubMed

Kitamura, Yutaka; Watanabe, Taisuke; Nakamura, Masayuki; Isobe, Kazushige; Kawabata, Hideo; Uematsu, Kohya; Okuda, Kazuhiro; Nakata, Koh; Tanaka, Takaaki; Kawase, Tomoyuki

2018-01-01

Platelet-rich fibrin (PRF) clots have been used in regenerative dentistry most often, with the assumption that growth factor levels are concentrated in proportion to the platelet concentration. Platelet counts in PRF are generally determined indirectly by platelet counting in other liquid fractions. This study shows a method for direct estimation of platelet counts in PRF. To validate this method by determination of the recovery rate, whole-blood samples were obtained with an anticoagulant from healthy donors, and platelet-rich plasma (PRP) fractions were clotted with CaCl 2 by centrifugation and digested with tissue-plasminogen activator. Platelet counts were estimated before clotting and after digestion using an automatic hemocytometer. The method was then tested on PRF clots. The quality of platelets was examined by scanning electron microscopy and flow cytometry. In PRP-derived fibrin matrices, the recovery rate of platelets and white blood cells was 91.6 and 74.6%, respectively, after 24 h of digestion. In PRF clots associated with small and large red thrombi, platelet counts were 92.6 and 67.2% of the respective total platelet counts. These findings suggest that our direct method is sufficient for estimating the number of platelets trapped in an insoluble fibrin matrix and for determining that platelets are distributed in PRF clots and red thrombi roughly in proportion to their individual volumes. Therefore, we propose this direct digestion method for more accurate estimation of platelet counts in most types of platelet-enriched fibrin matrix.

Platelet Counts in Insoluble Platelet-Rich Fibrin Clots: A Direct Method for Accurate Determination

PubMed Central

Kitamura, Yutaka; Watanabe, Taisuke; Nakamura, Masayuki; Isobe, Kazushige; Kawabata, Hideo; Uematsu, Kohya; Okuda, Kazuhiro; Nakata, Koh; Tanaka, Takaaki; Kawase, Tomoyuki

2018-01-01

Platelet-rich fibrin (PRF) clots have been used in regenerative dentistry most often, with the assumption that growth factor levels are concentrated in proportion to the platelet concentration. Platelet counts in PRF are generally determined indirectly by platelet counting in other liquid fractions. This study shows a method for direct estimation of platelet counts in PRF. To validate this method by determination of the recovery rate, whole-blood samples were obtained with an anticoagulant from healthy donors, and platelet-rich plasma (PRP) fractions were clotted with CaCl2 by centrifugation and digested with tissue-plasminogen activator. Platelet counts were estimated before clotting and after digestion using an automatic hemocytometer. The method was then tested on PRF clots. The quality of platelets was examined by scanning electron microscopy and flow cytometry. In PRP-derived fibrin matrices, the recovery rate of platelets and white blood cells was 91.6 and 74.6%, respectively, after 24 h of digestion. In PRF clots associated with small and large red thrombi, platelet counts were 92.6 and 67.2% of the respective total platelet counts. These findings suggest that our direct method is sufficient for estimating the number of platelets trapped in an insoluble fibrin matrix and for determining that platelets are distributed in PRF clots and red thrombi roughly in proportion to their individual volumes. Therefore, we propose this direct digestion method for more accurate estimation of platelet counts in most types of platelet-enriched fibrin matrix. PMID:29450197

Topical Combinations to Treat Microvascular Dysfunction of Chronic Postischemia Pain

PubMed Central

Laferrière, André; Abaji, Rachid; Tsai, Cheng-Yu Mark; Ragavendran, J. Vaigunda; Coderre, Terence J.

2015-01-01

Background Growing evidence indicates that patients with complex regional pain syndrome (CRPS) exhibit tissue abnormalities caused by microvascular dysfunction in the blood vessels of skin, muscle and nerve. We tested whether topical combinations aimed at improving microvascular function would relieve allodynia in an animal model of CRPS. We hypothesized that topical administration of either α2-adrenergic (α2A) receptor agonists or nitric oxide (NO) donors given to increase arterial blood flow, combined with either phosphatidic acid (PA) or phosphodiesterase (PDE) inhibitors to increase capillary blood flow, would effectively reduce allodynia and signs of microvascular dysfunction in the animal model of chronic pain. Methods Mechanical allodynia was induced in the hind paws of rats with chronic postischemia pain (CPIP). Allodynia was assessed before and after topical application of vehicle, single drugs or combinations of an α2A receptor agonist (apraclonidine) or an NO donor (linsidomine), with PA or PDE inhibitors (lisofylline, pentoxifylline). A topical combination of apraclonidine + lisofylline was also evaluated for its effects on a measure of microvascular function (post-occlusive reactive hyperemia) and tissue oxidative capacity (formazan production by tetrazolium reduction) in CPIP rats. Results Each of the single topical drugs produced significant dose-dependent antiallodynic effects compared to vehicle in CPIP rats (n = 30), and the antiallodynic dose-response curves of either PA or PDE inhibitors were shifted 5 to 10 fold to the left when combined with nonanalgesic doses of α2A receptor agonists or NO donors (n = 28). The potent antiallodynic effects of ipsilateral treatment with combinations of α2A receptor agonists or NO donors with PA or PDE inhibitors, were not reproduced by the same treatment of the contralateral hindpaw (n = 28). Topical combinations produced antiallodynic effects lasting up to 6 h (n = 15), and were significantly enhanced by low dose systemic pregabalin in early, but not late, CPIP rats (n = 18). An antiallodynic topical combination of apraclonidine + lisofylline was also found to effectively relieve depressed post-occlusive reactive hyperemia in CPIP rats (n = 61), and to increase formazan production in postischemic tissues (skin and muscle) (n = 56). Conclusions The present results support the hypothesis that allodynia in an animal model of CRPS is effectively relieved by topical combinations of α2A receptor agonists or NO donors with PA or PDE inhibitors. This suggests that topical treatments aimed at improving microvascular function by increasing both arterial and capillary blood flow produce effective analgesia for CRPS. PMID:24651238

The characterization of exosome from blood plasma of patients with colorectal cancer

NASA Astrophysics Data System (ADS)

Yunusova, N. V.; Tamkovich, S. N.; Stakheeva, M. N.; Afanas'ev, S. G.; Frolova, A. Y.; Kondakova, I. V.

2016-08-01

Exosomes are extracellular membrane structures involved in many physiological and pathological processes including cancerogenesis and metastasis. The clarification of the criteria for exosome isolating and identifying is the purpose of this study. Exosome samples from the plasma of patients with colorectal cancer and healthy donors were examined using transmission electron microscopy and flow cytometry in accordance with the minimum requirements of "International Society for Extracellular Vesicles". The choice of the method for isolation of exosomes from the blood plasma by ultrafiltration and ultracentrifugation allowed obtaining highly purified samples of exosomes, in which all the structural components were clearly seen. The results obtained with flow cytometry suggest that exosomes of blood plasma from patients with colorectal cancer can be produced by epithelial cells. Moreover, cells produce different types of exosomes, which correspond to different mechanisms in sorting macromolecules in the membrane of multivesicular bodies. Determination of significant differences in the expression of specific exosomal proteins from colorectal cancer patients compared to healthy donors suggests a high diagnostic potential significance of circulating exosomes.

Clinical utility of colour flow Doppler ultrasonography in planning anterolateral thigh flap harvest.

PubMed

Patel, Rajan S; Higgins, Kevin M; Enepekides, Danny J; Hamilton, Paul A

2010-10-01

The anatomic variability of cutaneous perforators contributes to the technical challenges of anterolateral thigh (ALT) free flap harvest. The objective of this study was to assess the accuracy and clinical utility of preoperative colour flow Doppler (CFD) ultrasonography in evaluating planned ALT flap donor sites. A prospective study of the infrainguinal vasculature (profunda femoris and lateral circumflex femoral arteries) in 16 consecutive patients scheduled for ALT free flap transfer for reconstruction of head and neck surgical defects was undertaken. All patients underwent CFD ultrasonography. The location of perforators and the thigh thickness determined by CFD ultrasonography were correlated with the actual intraoperative findings using a scatter plot and paired t-test. Two patients were diagnosed with bilateral silent infrainguinal claudication, which precluded safe use of the ALT donor site. In two other patients, the planned ALT donor site ipsilateral to the defect was not used because of silent infrainguinal claudication diagnosed by CFD ultrasonography. In the 14 patients who underwent ALT flap harvest, CFD ultrasonography identified 48 perforators, which coincided with 43 actual perforators found intraoperatively. CFD ultrasonography demonstrated a statistically significant correlation with the actual perforator locations (Spearman coefficient .76; p = .55). Although CFD ultrasonography tended to underestimate flap thickness, there was a statistically significant correlation (Spearman coefficient .94; p ≤ .0001) with the actual flap thickness. CFD ultrasonography has clinical utility in facilitating decision making and planning ALT flap harvest.

Enhancement of IR and VCD intensities due to charge transfer.

PubMed

Nicu, Valentin Paul; Autschbach, Jochen; Baerends, Evert Jan

2009-03-14

Donor-acceptor interactions such as the one between the Cl(-) base and the N-H sigma* acceptor orbitals encountered in the complexation of Cl(-) counterions to the [Co(en)(3)](3+) transition metal complex, have been shown to cause huge enhancement (between 1 and 2 orders of magnitude) of the VCD intensities of N-H stretching modes. This effect has been fully analyzed, and could be attributed to increased charge flow from the Cl(-) donors when the N-H bonds become stretched. The transfer of charge counteracts the movement of negative electronic charge that happens along with the motion of the H nuclei, effectively reversing the electronic part of the electric dipole transition moment (EDTM) in the direction of the charge flow (z, say), and of the magnetic transition dipole moment (MDTM) in the perpendicular direction. The consequences for the IR and VCD intensity follow: IR intensity is strongly increased if the EDTM is polarized in the z direction, e.g. in A(2) modes, but not so much if it is polarized in the xy plane (E modes), the VCD is strongly enhanced if the EDTM and MTDM are polarized in the xy plane (in E modes), but less so when they are polarized in the z direction (in A(2) modes). The explanation holds generally for complexation phenomena of this sort, including the donor-acceptor part of hydrogen bonding interactions, e.g. with solvent molecules.

Expanding the Donor Pool Through Intensive Care to Facilitate Organ Donation: Results of a Spanish Multicenter Study.

PubMed

Domínguez-Gil, Beatriz; Coll, Elisabeth; Elizalde, José; Herrero, Jaime E; Pont, Teresa; Quindós, Brígida; Marcelo, Bella; Bodí, María A; Martínez, Adolfo; Nebra, Agustín; Guerrero, Francisco; Manciño, José M; Galán, Juan; Lebrón, Miguel; Miñambres, Eduardo; Matesanz, Rafael

2017-08-01

Intensive Care to facilitate Organ Donation (ICOD) may help to increase the donor pool. We describe the Spanish experience with ICOD. Achieving Comprehensive Coordination in Organ Donation (ACCORD)-Spain consisted of an audit of the donation pathway from patients who died as a result of a devastating brain injury (possible donors) in 68 hospitals during November 1, 2014, to April 30, 2015. We focused on possible donors whose families were interviewed to discuss organ donation once intensive care with a therapeutic purpose was deemed futile and brain death (BD) was a likely outcome. Of the 1970 possible donors in ACCORD-Spain, in 257, the family was interviewed once the decision had been made not to intubate/ventilate (n = 105), with the patient under intubation/ventilation outside of the intensive care unit (n = 59), or with the patient intubated/ventilated within the intensive care unit (n = 93).Consent to ICOD was obtained in 174 cases. Consent was higher when the donor coordinator participated in the interview (odds ratio, 2.32; 95% confidence interval, 1.33-4.11; P = 0.003). One hundred thirty-one patients developed BD, of whom 117 transitioned to actual donation after BD. Of the 35 patients who did not develop BD, 2 transitioned to actual donation after circulatory death. Sixteen patients subject to ICOD were finally medically unsuitable organ donors.ICOD contributed to 24% of the 491 actual donors registered in ACCORD-Spain. Despite the complexity of the interview, the majority of families consented to ICOD. Estimating the probability of BD and assessing medical suitability are additional challenges of the practice. ICOD represents a clear opportunity to increase the donor pool and ensures organ donation is posed at every end-of-life care pathway.

Global-scale regionalization of hydrological model parameters using streamflow data from many small catchments

NASA Astrophysics Data System (ADS)

Beck, Hylke; de Roo, Ad; van Dijk, Albert; McVicar, Tim; Miralles, Diego; Schellekens, Jaap; Bruijnzeel, Sampurno; de Jeu, Richard

2015-04-01

Motivated by the lack of large-scale model parameter regionalization studies, a large set of 3328 small catchments (< 10000 km2) around the globe was used to set up and evaluate five model parameterization schemes at global scale. The HBV-light model was chosen because of its parsimony and flexibility to test the schemes. The catchments were calibrated against observed streamflow (Q) using an objective function incorporating both behavioral and goodness-of-fit measures, after which the catchment set was split into subsets of 1215 donor and 2113 evaluation catchments based on the calibration performance. The donor catchments were subsequently used to derive parameter sets that were transferred to similar grid cells based on a similarity measure incorporating climatic and physiographic characteristics, thereby producing parameter maps with global coverage. Overall, there was a lack of suitable donor catchments for mountainous and tropical environments. The schemes with spatially-uniform parameter sets (EXP2 and EXP3) achieved the worst Q estimation performance in the evaluation catchments, emphasizing the importance of parameter regionalization. The direct transfer of calibrated parameter sets from donor catchments to similar grid cells (scheme EXP1) performed best, although there was still a large performance gap between EXP1 and HBV-light calibrated against observed Q. The schemes with parameter sets obtained by simultaneously calibrating clusters of similar donor catchments (NC10 and NC58) performed worse than EXP1. The relatively poor Q estimation performance achieved by two (uncalibrated) macro-scale hydrological models suggests there is considerable merit in regionalizing the parameters of such models. The global HBV-light parameter maps and ancillary data are freely available via http://water.jrc.ec.europa.eu.

Do Sector Wide Approaches for health aid delivery lead to 'donor-flight'? A comparison of 46 low-income countries.

PubMed

Sweeney, Rohan; Mortimer, Duncan; Johnston, David W

2014-03-01

Sector Wide Approaches (SWAp) emerged during the 1990s as a new policy mechanism for aid delivery. Eschewing many features of traditional project-based aid, SWAps give greater control of aid allocation to recipient countries. Some critics have questioned whether reducing a donor's level of influence over aid allocation might lead to a decrease in donor contributions. While some qualitative evaluations have described the level of fund pooling and donor participation in SWAps, no previous study has empirically examined this potential 'donor-flight' response to health SWAp implementation. This paper utilises a uniquely compiled dataset of 46 low-income countries over 1990-2009 and a variety of panel data regression models to estimate the impact of health SWAp implementation on levels of health aid. Results suggest that amongst 16 especially poor low-income countries, SWAp implementation is associated with significant decreases in health aid levels compared with non-implementers. This suggests donors are not indifferent to how their contributions are allocated by recipients, and that low-income countries considering a SWAp may need to weigh the benefits of greater control of aid allocations against the possibility of reduced aid income. Copyright © 2013 Elsevier Ltd. All rights reserved.

Prevalence of human T-cell lymphotropic virus types 1 and 2 in blood donors of the Caruaru Blood Center (Hemope).

PubMed

de Lima, Waleska Mayara Gomes; Esteves, Fabrício Andrade Martins; Torres, Maria do Carmo Morais Rodrigues; Pires, Edna Suely Feitosa

2013-01-01

There is difficulty in gathering data on the prevalence of human T-cell lymphotropic virus in blood donors as confirmatory testing is not mandatory in Brazil. This suggests there may be an underreporting of the prevalence. To estimate the prevalence of human T-cell lymphotropic virus types 1 and 2 in donors of a blood bank in Caruaru, Brazil. This was an observational, epidemiological, descriptive, longitudinal and retrospective study with information about the serology of donors of the Caruaru Blood Center, Fundação de Hematologia e Hemoterapia de Pernambuco (Hemope) from May 2006 to December 2010. The data were analyzed using the Excel 2010 computer program (Microsoft Office(®)). Of 61,881 donors, 60 (0.096%) individuals were identified as potential carriers of human T-cell lymphotropic virus types 1 and 2. Of these, 28 (0.045%) were positive and 32 (0.051%) had inconclusive results in the serological screening. Forty-five (0.072%) were retested; 17 were positive (0.027%) and 3 inconclusive (0.005%). After confirmatory tests, 8 were positive (0.013%). Six (75%) of the confirmed cases were women. Epidemiological surveys like this are very important in order to create campaigns to attract donors and reduce the costs of laboratory tests.

Prevalence of Human T-lymphotropic virus type 1 and 2 among blood donors in Manaus, Amazonas State, Brazil

PubMed Central

de Morais, Márcia Poinho EncarnaçÃo; Gato, Cynara Melo; Maciel, Lucinei Alves; Lalwani, Pritesh; Costa, Cristóvão Alves; Lalwani, Jaila Dias Borges

2017-01-01

ABSTRACT Introduction: Human T-lymphotropic virus type 1 and 2 (HTLV-1/2) is endemic in Brazil, but few studies have investigated the seroprevalence of HTLV and its subtypes among blood donors in the capital city Manaus, Amazonas State, Brazil. Aim: To estimate the seroprevalence of HTLV-1/2 and to identify circulating subtypes among blood donors in Manaus. Materials and Methods: Blood donors (2001-2003) were screened for HTLV-1/2 antibodies by ELISA. Positive results were confirmed and subtyped by Western blot assays. Prevalence rates were calculated and compared with demographic data. Results: Among the 87,402 individuals screened, 116 (0.13%) were seropositive for HTLV-1/2. A second sample (76/116) was collected and retested by HTLV-1/2 ELISA, of which only 41/76 were positive. Western blot confirmed HTLV infection in 24/41 retested blood donors [HTLV-1 (n=16), HTLV-2 (n=5) and HTLV-untypable (n=3)]. Discussion: HTLV-1 and HTLV-2 are prevalent among blood donors in Manaus. However, additional studies are needed to comprehend the epidemiology of HTLV-1/2 in Amazonas not only to understand the pathophysiology of the disease providing adequate medical assistance, but also to reduce or block virus transmission. PMID:29267588

Validation of the multiplex ligation-dependent probe amplification assay and its application on the distribution study of the major alleles of 17 blood group systems in Chinese donors from Guangzhou.

PubMed

Ji, Yanli; Wen, Jizhi; Veldhuisen, Barbera; Haer-Wigman, Lonneke; Wang, Zhen; Lodén-van Straaten, Martin; Wei, Ling; Luo, Guangping; Fu, Yongshui; van der Schoot, C Ellen

2017-02-01

Genotyping platforms for common red blood cell (RBC) antigens have been successfully applied in Caucasian and black populations but not in Chinese populations. In this study, a genotyping assay based on multiplex ligation-dependent probe amplification (MLPA) technology was applied in a Chinese population to validate the MLPA probes. Subsequently, the comprehensive distribution of 17 blood group systems also was obtained. DNA samples from 200 Chinese donors were extracted and genotyped using the blood-MLPA assay. To confirm the MLPA results, a second independent genotyping assay (ID Core+) was conducted in 40 donors, and serological typing of 14 blood-group antigens was performed in 91 donors. In donors who had abnormal copy numbers of an allele (DI and GYPB) determined by MLPA, additional experiments were performed (polymerase chain reaction, sequencing, and flow cytometry analysis). The genotyping results obtained using the blood-MLPA and ID Core+ assays were consistent. Serological data were consistent with the genotyping results except for one donor who had a Lu(a-b-) phenotype. Of the 17 blood group systems, the distribution of the MNS, Duffy, Kidd, Diego, Yt, and Dombrock systems was polymorphic. The Mur and St a antigens of the MNS system were distributed with a frequency of 9% (18 of 200) and 2% (4 of 200), respectively. One donor with chimerism and one who carried a novel DI*02(A845V) allele, which predicts the depression of Di b antigen expression, were identified. The blood-MLPA assay could easily identify the common blood-group alleles and correctly predicted phenotype in the Chinese population. The Mur and St a antigens were distributed with high frequency in a Southern Chinese Han population. © 2016 AABB.

Ten years cardiovascular risk estimation according to Framingham score and non HDL-cholesterol in blood donors.

PubMed

Graffigna, Mabel Nora; Berg, Gabriela; Migliano, Marta; Salgado, Pablo; Soutelo, Jimena; Musso, Carla

2015-01-01

Cardiovascular disease (CVD) is currently the primary cause of morbidity and mortality. (1) Assess the 10 years risk for CVD in Argentinean blood donors, according to Framingham score (updated by ATP III), (2) evaluate the prevalence of the MS, (3) evaluate non HDL-cholesterol level in this population as other risk for CVD. A prospective, epidemiological, transversal study was performed to evaluate 585 volunteer blood donors for two years. Non HDL-C was calculated as total cholesterol minus HDL-C and we evaluated the 10 years risk for CVD according to Framingham score (updated by ATP III). Metabolic syndrome prevalence was estimated according to ATP III and IDF criteria. Non HDL-C was (media±SD) 178.3±48.0 mg/dl in participants with MS and 143.7±39.3 mg/dl without MS (ATPIII) and 160.1±43.6 mg/dl in participants with MS and 139.8±43.1 mg/dl without MS (IDF). Participants with MS presented an OR of 3.1; IC 95% (2-5) of CVD according to de Framingham score. Individuals with MS and elevated non HDL-C are at a higher estimated risk for cardiovascular events in the next 10 years according to the Framingham risk score. Copyright © 2014. Published by Elsevier Ltd.

Pretransplantation recipient regulatory T cell suppressive function predicts delayed and slow graft function after kidney transplantation.

PubMed

Nguyen, Minh-Tri J P; Fryml, Elise; Sahakian, Sossy K; Liu, Shuqing; Michel, Rene P; Lipman, Mark L; Mucsi, Istvan; Cantarovich, Marcelo; Tchervenkov, Jean I; Paraskevas, Steven

2014-10-15

Delayed graft function (DGF) and slow graft function (SGF) are a continuous spectrum of ischemia-reperfusion-related acute kidney injury (AKI) that increases the risk for acute rejection and graft loss after kidney transplantation. Regulatory T cells (Tregs) are critical in transplant tolerance and attenuate murine AKI. In this prospective observational cohort study, we evaluated whether pretransplantation peripheral blood recipient Treg frequency and suppressive function are predictors of DGF and SGF after kidney transplantation. Deceased donor kidney transplant recipients (n=53) were divided into AKI (n=37; DGF, n=10; SGF, n=27) and immediate graft function (n=16) groups. Pretransplantation peripheral blood CD4CD25FoxP3 Treg frequency was quantified by flow cytometry. Regulatory T-cell suppressive function was measured by suppression of autologous effector T-cell proliferation by Treg in co-culture. Pretransplantation Treg suppressive function, but not frequency, was decreased in AKI recipients (P<0.01). In univariate and multivariate analyses accounting for the effects of cold ischemic time and donor age, Treg suppressive function discriminated DGF from immediate graft function recipients in multinomial logistic regression (odds ratio, 0.77; P<0.01), accurately predicted AKI in receiver operating characteristic curve (area under the curve, 0.82; P<0.01), and predicted 14-day estimated glomerular filtration rate in linear regression (P<0.01). Our results indicate that recipient peripheral blood Treg suppressive function is a potential independent pretransplantation predictor of DGF and SGF.

Assessing the effect of a partly unobserved, exogenous, binary time-dependent covariate on survival probabilities using generalised pseudo-values.

PubMed

Pötschger, Ulrike; Heinzl, Harald; Valsecchi, Maria Grazia; Mittlböck, Martina

2018-01-19

Investigating the impact of a time-dependent intervention on the probability of long-term survival is statistically challenging. A typical example is stem-cell transplantation performed after successful donor identification from registered donors. Here, a suggested simple analysis based on the exogenous donor availability status according to registered donors would allow the estimation and comparison of survival probabilities. As donor search is usually ceased after a patient's event, donor availability status is incompletely observed, so that this simple comparison is not possible and the waiting time to donor identification needs to be addressed in the analysis to avoid bias. It is methodologically unclear, how to directly address cumulative long-term treatment effects without relying on proportional hazards while avoiding waiting time bias. The pseudo-value regression technique is able to handle the first two issues; a novel generalisation of this technique also avoids waiting time bias. Inverse-probability-of-censoring weighting is used to account for the partly unobserved exogenous covariate donor availability. Simulation studies demonstrate unbiasedness and satisfying coverage probabilities of the new method. A real data example demonstrates that study results based on generalised pseudo-values have a clear medical interpretation which supports the clinical decision making process. The proposed generalisation of the pseudo-value regression technique enables to compare survival probabilities between two independent groups where group membership becomes known over time and remains partly unknown. Hence, cumulative long-term treatment effects are directly addressed without relying on proportional hazards while avoiding waiting time bias.

Cost and Cost-Effectiveness of Donor Human Milk to Prevent Necrotizing Enterocolitis: Systematic Review.

PubMed

Buckle, Abigail; Taylor, Celia

2017-11-01

Necrotizing enterocolitis (NEC) is a costly gastrointestinal disorder that mainly affects preterm and low-birth-weight infants and can lead to considerable morbidity and mortality. Mother's own milk is protective against NEC but is not always available. In such cases, donor human milk has also been shown to be protective (although to a lesser extent) compared with formula milk, but it is more expensive. This systematic review aimed at evaluating the cost of donor milk, the cost of treating NEC, and the cost-effectiveness of exclusive donor milk versus formula milk feeding to reduce the short-term health and treatment costs of NEC. We systematically searched five relevant databases to find studies with verifiable costs or charges of donor milk and/or treatment of NEC and any economic evaluations comparing exclusive donor milk with exclusive formula milk feeding. All search results were double screened. Seven studies with verifiable donor milk costs and 17 with verifiable NEC treatment costs were included. The types of cost or charge included varied considerably across studies, so quantitative synthesis was not attempted. Estimates of the incremental length of stay associated with NEC were ∼18 days for medical NEC and 50 days for surgical NEC. Two studies claimed to report economic evaluations but did not do so in practice. It is likely that donor milk provides short-term cost savings by reducing the incidence of NEC. Future studies should provide more details on cost components included and a full economic evaluation, including long-term outcomes, should be undertaken.

Outcomes of simultaneous pancreas-kidney transplantation from brain-dead and controlled circulatory death donors.

PubMed

Qureshi, M S; Callaghan, C J; Bradley, J A; Watson, C J E; Pettigrew, G J

2012-06-01

Organ scarcity has prompted increased use of organs from donation after circulatory death (DCD) donors. An early single-centre experience of simultaneous pancreas-kidney (SPK) transplantation from controlled DCD donors is described here. Outcomes of SPK transplants from DCD and donation after brain death (DBD) donors between August 2008 and January 2011 were reviewed retrospectively. SPK transplants from 20 DCD and 40 DBD donors were carried out. Donor and recipient characteristics were similar for both groups, although pancreas cold ischaemia times were shorter in DCD recipients: median (range) 8·2 (5·9-10·5) versus 9·5 (3·8-12·5) h respectively (P = 0·004). Median time from treatment withdrawal to cold perfusion was 24 (range 16-110) min for DCD donors. There were no episodes of delayed pancreatic graft function in either group; the graft thrombosis rates were both 5 per cent. Similarly, there were no differences in haemoglobin A1c level at 12 months: median (range) 5·4 (4·9-7·7) per cent in DCD group versus 5·4 (4·1-6·2) per cent in DBD group (P = 0·910). Pancreas graft survival rates were not significantly different, with Kaplan-Meier 1-year survival estimates of 84 and 95 per cent respectively (P = 0·181). DCD SPK grafts had comparable short-term outcomes to DBD grafts, even when procured from selected donors with a prolonged agonal phase. Copyright © 2012 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

Application of Fuzzy Logic in Oral Cancer Risk Assessment.

PubMed

Scrobotă, Ioana; Băciuț, Grigore; Filip, Adriana Gabriela; Todor, Bianca; Blaga, Florin; Băciuț, Mihaela Felicia

2017-05-01

The mapping of the malignization mechanism is still incomplete, but oxidative stress is strongly correlated to carcinogenesis. In our research, using fuzzy logic, we aimed to estimate the oxidative stress related-cancerization risk of the oral potentially malignant disorders. Serum from 16 patients diagnosed (clinical and histopathological) with oral potentially malignant disorders (Dept. of Cranio-Maxillofacial Surgery and Radiology, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj Napoca, Romania) was processed fluorometric for malondialdehyde and proton donors assays (Dept. of Physiology,"Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania). The values were used as inputs, they were associated linguistic terms using MIN-MAX method and 25 IF-THEN inference rules were generated to estimate the output value, the cancerization risk appreciated on a scale from 1 to 10 - IF malondialdehyde is very high and donors protons are very low THEN the cancer risk is reaching the maximum value (Dept. of Industrial Engineering, Faculty of Managerial and Technological Engineering, University of Oradea, Oradea, Romania) (2012-2014). We estimated the cancerization risk of the oral potentially malignant disorders by implementing the multi-criteria decision support system based on serum malondialdehyde and proton donors' values. The risk was estimated as a concrete numerical value on a scale from 1 to 10 depending on the input numerical/linguistic value. The multi-criteria decision support system proposed by us, integrated into a more complex computerized decision support system, could be used as an important aid in oral cancer screening and establish future medical decision in oral potentially malignant disorders.

Accurate method for preoperative estimation of the right graft volume in adult-to-adult living donor liver transplantation.

PubMed

Khalaf, H; Shoukri, M; Al-Kadhi, Y; Neimatallah, M; Al-Sebayel, M

2007-06-01

Accurate estimation of graft volume is crucial to avoid small-for-size syndrome following adult-to-adult living donor liver transplantation AALDLT). Herein, we combined radiological and mathematical approaches for preoperative assessment of right graft volume. The right graft volume was preoperatively estimated in 31 live donors using two methods: first, the radiological graft volume (RGV) by computed tomography (CT) volumetry and second, a calculated graft volume (CGV) obtained by multiplying the standard liver volume by the percentage of the right graft volume (given by CT). Both methods were compared to the actual graft volume (AGV) measured during surgery. The graft recipient weight ratio (GRWR) was also calculated using all three volumes (RGV, CGV, and AGV). Lin's concordance correlation coefficient (CCC) was used to assess the agreement between AGV and both RGV and CGV. This was repeated using the GRWR measurements. The mean percentage of right graft volume was 62.4% (range, 55%-68%; SD +/- 3.27%). The CCC between AGV and RGV versus CGV was 0.38 and 0.66, respectively. The CCC between GRWR using AGV and RGV versus CGV was 0.63 and 0.88, respectively (P < .05). According to the Landis and Kock benchmark, the CGV correlated better with AGV when compared to RGV. The better correlation became even more apparent when applied to GRWR. In our experience, CGV showed a better correlation with AGV compared with the RGV. Using CGV in conjunction with RGV may be of value for a more accurate estimation of right graft volume for AALDLT.

Philanthropy and hospital financing.

PubMed Central

Smith, D G; Clement, J P; Wheeler, J R

1995-01-01

OBJECTIVE. This study explores the relationships among donations to not-for-profit hospitals, the returns provided by these hospitals, and fund-raising efforts. It tests a model of hospital behavior and addresses an earlier debate regarding the supply price of donations. DATA SOURCES. The main data source is the California Office of Statewide Health Planning data tapes of hospital financial disclosure reports for fiscal years 1980/1981 through 1986/1987. Complete data were available for 160 hospitals. STUDY DESIGN. Three structural equations (donations, returns, and fund-raising) are estimated as a system using a fixed-effects, pooled cross-section, time-series least squares regression. PRINCIPAL FINDINGS. Estimation results reveal the expected positive relation between donations and returns. The reverse relation between returns and donations is insignificant. The estimated effect of fund-raising on donations is insignificantly different from zero, and the effect of donations on fund-raising is negative. Fund-raising and returns are negatively associated with one another. CONCLUSION. The empirical results presented here suggest a positive donations-returns relations and are consistent with a positive supply price for donations. Hospitals appear to view a trade-off between providing returns and soliciting donations, but donors do not respond equally to these two activities. Attempts to increase free cash flow through expansion of community returns or fund-raising activity, at least in the short run, are not likely to be highly successful financing strategies for many hospitals. PMID:8537223

Donation FAQs (Bone and Tissue Allografts)

MedlinePlus

... about organ, tissue and eye donation in your state, visit www.donatelife.net . Is there a difference between tissue and organ donation? In order for a person to become an organ donor (kidney, heart, liver, lung), blood and oxygen must flow through the organs until the time of recovery ...

Long-Term Safety of Short-Term Administration of Filgrastim (rhG-CSF) and Leukophresis Procedure in Healthy Children: Application of Peripheral Blood Stem Cell Collection in Pediatric Donors.

PubMed

Behfar, Maryam; Faghihi-Kashani, Sara; Hosseini, Ashraf Sadat; Ghavamzadeh, Ardeshir; Hamidieh, Amir Ali

2018-04-01

Administration of filgrastim (recombinant human granulocyte colony-stimulating factor [rhG-CSF]) (Neupogen) in healthy donors to mobilize hematopoietic stem cells (HSCs) is a widespread practice in adults. Application of peripheral blood stem cell (PBSC) collection in normal pediatric donors is scarce due to ethical issues. Hence, there are insufficient data on the long-term impact of PBSC procedure in healthy children. This retrospective study aimed to evaluate the early and late adverse effects of PBSC donation in pediatric donors. Bone marrow and PBSC procedures and known adverse events of each technique were completely explained to parents and when applicable to children and written informed consent was obtained. rhG-CSF was administered for 4 days. HSCs were collected on the fifth day through continuous-flow apheresis and donors were followed for 30 days. Manual chart review was performed to collect short-term complications. Donors' health status was assessed via a questionnaire. A total of 145 healthy pediatric donors with a median age of 10 years at the time of donation (2 to 15 years) were followed for a median of 4.8 years (range, 1.2 to 14.2 years). The most frequent symptoms of rhG-CSF administration were fatigue (5%) and headache (3%). Thirty-five (24%) donors experienced hypocalcaemia during apheresis procedure that quickly responded to treatment. Two pregnancies occurred after rhG-CSF administration that resulted in normal births. We did not encounter any serious adverse events, including neoplastic disorders and death in this study. rhG-CSF and leukophresis procedure were well-tolerated in this study and all children completed the donation process without interruption or reduction of rhG-CSF dosage. Our results suggest that rhG-CSF is a safe drug in healthy children for the purpose of HSC mobilization. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Exchange donor transplantation: ethical option for living renal transplantation.

PubMed

Gürkan, A; Kaçar, S; Varılsuha, C; Tilif, S; Turunç, V; Doǧan, M; Dheir, H; Sahin, S

2011-04-01

Taking in consideration the opinion of our team, which necessitates obligation of a relative relation between donors and recipients (genetic or matrimonial), we performed donor exchanges as an ethical alternative in living donor transplantations. We reviewed the outcomes of our exchange series. Between July 2003 and August 2010 we performed 110 exchange donor transplantations in four hospitals: one four-way, two three-way, and 100 two-way cases. Donors were mostly spouses (n = 71) or mothers (n = 15). The mean age of the donors was 48.8 (range = 23-69) and the recipients 41.4 years (range = 5-66). Two were transplanted preemptively and the others had a mean dialysis duration of 43 months (range = 1-120). Among 110 patients, three compatible pairs joined the group voluntarily; 71, due to ABO incompatibility and 36, due to crossmatch positivity. Induction therapy was used in 92 patients. HLA mismatches (MM) were: one MM in three; two MM in three; three MM in 18, four MM in 36; five MM in 34; and six MM in 18. Among 90 patients tested for panel-reactive antibodies PRA, five showed class I and 10, class II positivity. In 11 patients, B-cell positivity was detected by flow cytometry. Delayed graft function (n = 2), acute rejection (n = 11), BK virus infection (n = 1), and cytomegalovirus infection (n = 3) were seen postoperatively. Three (2.7%) patients died due to sepsis. Five patients returned to dialysis program due to interstitial fibrosis tubular atrophy (IFTA) (n = 2), renal vein thrombosis (n = 1), de novo glomerulopathy (n = 1), or primary nonfunction (n = 1). The 1- and 5-year patient and graft survival rates were 96% and 96%, 95% and 89%, respectively. We believe that exchange donor transplantation is as successful as direct transplants; it is a good, ethical alternative to unrelated living transplantations. Copyright © 2011 Elsevier Inc. All rights reserved.

Iron-deficient erythropoiesis in blood donors and red blood cell recovery after transfusion: initial studies with a mouse model

PubMed Central

Bandyopadhyay, Sheila; Brittenham, Gary M.; Francis, Richard O.; Zimring, James C.; Hod, Eldad A.; Spitalnik, Steven L.

2017-01-01

Background Most frequent red cell (RBC) donors and many first-time donors are iron deficient, but meet haemoglobin standards. However, the effects of donation-induced iron deficiency on RBC storage quality are unknown. Thus, we used a mouse model to determine if donor iron deficiency reduced post-transfusion RBC recovery. Methods Weanling mice received a control diet or an iron-deficient diet. A third group receiving the iron-deficient diet was also phlebotomised weekly. This provided 3 groups of mice with different iron status: (1) iron replete, (2) mild iron deficiency with iron-deficient erythropoiesis, and (3) iron-deficiency anaemia. At ten weeks of age, blood was collected, leucoreduced, and stored at 4 ºC. After 12 days of storage, 24-hour (h) post-transfusion RBC recovery was quantified in recipients by flow cytometry. Results Before blood collection, mean haemoglobin concentrations in the iron-replete, iron-deficient, and iron-deficiency anaemia donor mice were 16.5±0.4, 11.5±0.4, and 7.0±1.4 [g/dL± 1 standard deviation (SD)], respectively (p<0.01 for all comparisons between groups). The 24-h post-transfusion RBC recoveries in recipients receiving transfusions from these three cohorts were 77.1±13.2, 66.5±10.9, and 46.7±15.9 (% ±1 SD), respectively (p<0.05 for all comparisons between groups). Discussion In summary, donor iron deficiency significantly reduced 24-h post-transfusion RBC recovery in recipient mice. RBCs from mice with mild iron deficiency and iron-deficient erythropoiesis, with haemoglobin levels similar to those used for human autologous blood donation, had intermediate post-transfusion RBC recovery, as compared to iron-replete donors and those with iron-deficiency anaemia. This suggests that, in addition to the effects of iron deficiency on donor health, frequent blood donation, leading to iron-deficient erythropoiesis, may also have adverse effects for transfusion recipients. PMID:28263174

The corrected donor age for hepatitis C virus-infected liver transplant recipients.

PubMed

Dirchwolf, Melisa; Dodge, Jennifer L; Gralla, Jane; Bambha, Kiran M; Nydam, Trevor; Hung, Kenneth W; Rosen, Hugo R; Feng, Sandy; Terrault, Norah A; Biggins, Scott W

2015-08-01

Donor age has become the dominant donor factor used to predict graft failure (GF) after liver transplantation (LT) in hepatitis C virus (HCV) recipients. The purpose of this study was to develop and validate a model of corrected donor age (CDA) for HCV LT recipients that transforms the risk of other donor factors into the scale of donor age. We analyzed all first LT recipients with HCV in the United Network for Organ Sharing (UNOS) registry from January 1998 to December 2007 (development cohort, n = 14,538) and January 2008 to December 2011 (validation cohort, n = 7502) using Cox regression, excluding early GF (<90 days from LT). Accuracy in predicting 1 year GF (death or repeat LT) was assessed with the net reclassification index (NRI). In the development cohort, after controlling for pre-LT recipient factors and geotemporal trends (UNOS region, LT year), the following donor factors were independent predictors of GF, all P < 0.05: donor age (hazard ratio [HR], 1.02/year), donation after cardiac death (DCD; HR, 1.31), diabetes (HR, 1.23), height < 160 cm (HR, 1.13), aspartate aminotransferase (AST) ≥ 120 U/L (HR, 1.10), female (HR, 0.94), cold ischemia time (CIT; HR, 1.02/hour), and non-African American (non-AA) donor-African American (AA) recipient (HR, 1.65). Transforming these risk factors into the donor age scale yielded the following: DCD = +16 years; diabetes = +12 years; height < 160 cm = +7 years; AST ≥ 120 U/L = +5 years; female = -4 years; and CIT = +1 year/hour > 8 hours and -1 year/hour < 8 hours. There was a large effect of donor-recipient race combinations: +29 years for non-AA donor and an AA recipient but only +5 years for an AA donor and an AA recipient, and -2 years for an AA donor and a non-AA recipient. In a validation cohort, CDA better classified risk of 1-year GF versus actual age (NRI, 4.9%; P = 0.009) and versus the donor risk index (9.0%, P < 0.001). The CDA, compared to actual donor age, provides an intuitive and superior estimation of graft quality for HCV-positive LT recipients because it incorporates additional factors that impact LT GF rates. © 2015 American Association for the Study of Liver Diseases.

Superagonistic CD28 antibody induces donor-specific tolerance in rat renal allografts.

PubMed

Azuma, H; Isaka, Y; Li, X; Hünig, T; Sakamoto, T; Nohmi, H; Takabatake, Y; Mizui, M; Kitazawa, Y; Ichimaru, N; Ibuki, N; Ubai, T; Inamoto, T; Katsuoka, Y; Takahara, S

2008-10-01

The ultimate goal of organ transplantation is to establish graft tolerance where CD4+CD25+FOXP3+ regulatory T (Treg) cells play an important role. We examined whether a superagonistic monoclonal antibody specific for CD28 (CD28 SA), which expands Treg cells in vivo, would prevent acute rejection and induce tolerance using our established rat acute renal allograft model (Wistar to Lewis). In the untreated or mouse IgG-treated recipients, graft function significantly deteriorated with marked destruction of renal tissue, and all rats died by 13 days with severe azotemia. In contrast, 90% of recipients treated with CD28 SA survived over 100 days, and 70% survived with well-preserved graft function until graft recovery at 180 days. Analysis by flow cytometry and immunohistochemistry demonstrated that CD28 SA induced marked infiltration of FOXP3+ Treg cells into the allografts. Furthermore, these long-surviving recipients showed donor-specific tolerance, accepting secondary (donor-matched) Wistar cardiac allografts, but acutely rejecting third-party BN allografts. We further demonstrated that adoptive transfer of CD4+CD25+ Treg cells, purified from CD28 SA-treated Lewis rats, significantly prolonged allograft survival and succeeded in inducing donor-specific tolerance. In conclusion, CD28 SA treatment successfully induces donor-specific tolerance with the involvement of Treg cells, and thus the therapeutic value of this approach warrants further investigation and preclinical studies.

Serological Assessment for Leishmania donovani Infection in Blood Donors of Sunsari District, Dharan, Nepal.

PubMed

Timilsina, Suraj; Raj Bhattarai, Narayan; Khanal, Basudha; Rijal, Suman

2016-03-01

Visceral leishmaniasis (VL) is a major vector-borne disease caused by Leishmania donovani, after replication of the parasites in macrophages, mononuclear phagocytic system. VL is endemic in 12 districts of central and eastern Terai lowlands of Nepal bordering North Bihar, India with an estimated 8 million population at risk. In addition, VL endemicity is also extending to new endemic regions like Dharan from its classical rural foci. Hence, we aimed to detect the evidence of Leishmania donovani infection in the blood samples received from blood donors of Sunsari district, Dharan, (eastern Nepal), a region endemic for human VL. Sera from 507 asymptomatic blood donors were subjected to serological screening for anti-Leishmania donovani antibodies. Direct agglutination test (DAT) was performed on the sera. Out of 507 donors, majority (78.50 %) were male. Among the donors, 472 (93.10 %) belonged to age group 18-45 years where as 35 (6.90 %) to age group >45 years. Circulating anti-Leishmania antibodies were detected in 5 (1 %) out of 507 healthy, Human Immunodeficiency Virus types 1 and 2 (HIV 1and 2), Hepatitis B Surface Antigen (HBsAg), anti- Hepatitis C Virus (anti-HCV)-negative, and Syphillis non-reactive donors. All the seropositive cases were male and belonged to the age group 18-45 years. The result suggests that there is an immediate need of screening asymptomatic blood donors for leishmania seropositivity especially in endemic areas.

[Need and demand of kidneys for transplantation in Venezuela].

PubMed

Milanés, C L; Bellorín-Font, E; Weisinger, J; Pernalete, N; Urbina, D; Paz-Martínez, V

1993-01-01

The number of cadaveric kidneys available for transplantation has become insufficient around the world. Despite concerted efforts, we have been unsuccessful in greatly improve the supply of organ donors, and consequently the number of end stage renal failure patients awaiting for kidney transplantation continues to increase. The primary objective of this paper is to quantify the need and supply of kidneys for transplant in Venezuela. An overview of the current level of kidney transplant activity in Venezuela is presented, observing that the activity with cadaveric donors had been predominant since 1983, although not to an optimal level. The annual activity in kidney transplant between 1989-1991 remained stable in 6 transplants/million people, but went sharply down to 4.6 in 1992. An estimate of the current need is around 10 donors/million people. This is in contrast with an effective donation rate of only 2.01 and 1.92 donors/million achieved in 1990 and 1991 respectively. The most frequent cause for no donation was the lack of familiar consent. Based on an analysis of the factors involved in the shortage of donor supply in Venezuela, we present some recommendations to increase the availability of cadaveric organ donors in the country. These measures include an improvement of education and legal regulation in the field of organ donation and transplantation, and following the Spanish model, the creation of a program of hospital transplant coordinators that can detect and evaluate potential organ donors as well as coordinate the logistical aspects of transplantation.

Causes and timing of end-stage renal disease after living kidney donation.

PubMed

Matas, Arthur J; Berglund, Danielle M; Vock, David M; Ibrahim, Hassan N

2018-05-01

End-stage renal disease (ESRD) is a risk after kidney donation. We sought, in a large cohort of kidney donors, to determine the causes of donor ESRD, the interval from donation to ESRD, the role of the donor/recipient relationship, and the trajectory of the estimated GFR (eGFR) from donation to ESRD. From 1/1/1963 thru 12/31/2015, 4030 individuals underwent living donor nephrectomy at our center, as well as ascertainment of ESRD status. Of these, 39 developed ESRD (mean age ± standard deviation [SD] at ESRD, 62.4 ± 14.1 years; mean interval between donation and ESRD, 27.1 ± 9.8 years). Donors developing ESRD were more likely to be male, as well as smokers, and younger at donation, and to have donated to a first-degree relative. Of donors with a known cause of ESRD (n = 25), 48% was due to diabetes and/or hypertension; only 2 from a disease that would have affected 1 kidney (cancer). Of those 25 with an ascertainable ESRD cause, 4 shared a similar etiology of ESRD with their recipient. Almost universally, thechange of eGFR over time was stable, until new-onset disease (kidney or systemic). Knowledge of factors contributing to ESRD after living kidney donation can improve donor selection and counseling, as well as long-term postdonation care. © 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.

Heart Transplantation for Congenital Heart Disease in the First Year of Life

PubMed Central

Chinnock, Richard E; Bailey, Leonard L

2011-01-01

Successful infant heart transplantation has now been performed for over 25 years. Assessment of long term outcomes is now possible. We report clinical outcomes for322 patients who received their heart transplant during infancy. Actuarial graft survival for newborn recipients is 59% at 25 years. Survival has improved in the most recent era. Cardiac allograft vasculopathy is the most important late cause of death with an actuarial incidence at 25 years of 35%. Post-transplant lymphoma is estimated to occur in 20% of infant recipients by25 years. Chronic kidney disease grade 3 or worse is present in 31% of survivors. The epidemiology of infant heart transplantation has changed through the years as the results for staged repair improved and donor resources remained stagnant. Most centers now employ staged repair for hypoplastic left heart syndrome and similar extreme forms of congenital heart disease. Techniques for staged repair, including the hybrid procedure, are described. The lack of donors is described with particular note regarding decreased donors due to newer programs for appropriate infant sleep positioning and infant car seats. ABO incompatible donors are a newer resource for maximizing donor resources, as is donation after circulatory determination of death and techniques to properly utilize more donors by expanding the criteria for what is an acceptable donor. An immunological advantage for the youngest recipients has long been postulated, and evaluation of this phenomenon may provide clues to the development of accommodation and/or tolerance. PMID:22548030

Adverse reactions, psychological factors, and their effect on donor retention in men and women.

PubMed

Veldhuizen, Ingrid; Atsma, Femke; van Dongen, Anne; de Kort, Wim

2012-09-01

This study investigates the effect of a vasovagal reaction (VVR) or needle reaction (NR) on the risk of stopping as a blood donor, taking into account variables from the Theory of Planned Behavior (TPB). Is stopping risk solely related to the adverse reaction itself, or do the TPB variables play a role as well? Emphasis is placed on possible sex differences. TPB variables were assessed within 12,051 whole blood donors. Also, donors reported the occurrence of adverse reactions during or after their last donation. Blood bank records were used to determine whether donors stopped donating within the next 2 years. Logistic regression analyses were performed to estimate the effect of self-reported adverse reactions on stopping risk, adjusting for the TPB variables. Analyses were performed separately for both sexes. Men have a lower odds of reporting a NR or a VVR than women (odds ratio [OR] 0.34, 95% confidence interval [CI], 0.28-0.43; and OR 0.26, 95% CI 0.19-0.36, for NR and VVR, respectively). For both sexes, only a VVR was associated with stopping risk, which is higher in men (men, OR 3.95, 95% CI 2.19-7.11; women, OR 1.78, 95% CI 1.35-2.35). After adjusting for the TPB variables both ORs declined (men, OR 3.38, 95% CI 1.86-6.15; women, OR 1.58, 95% CI 1.17-2.14). Also, self-efficacy and affective attitude are negatively associated with adverse reactions. Female donors report more VVRs than male donors, but male donors have a higher stopping risk after a VVR than female donors. Coping differences and possible reporting tendencies might play a role. For donor retention purposes, prevention and coping techniques should take sex differences into account. © 2012 American Association of Blood Banks.

No significant differences in short-term renal prognosis between living kidney donors with and without diabetes.

PubMed

Shinzato, Takahiro; Kurosawa, Akira; Kubo, Taro; Shimizu, Toshihiro; Kimura, Takaaki; Nanmoku, Koji; Yagisawa, Takashi

2018-06-01

Renal prognosis in living kidney donors with diabetes is currently not known. In this study, we sought to investigate renal prognosis in living kidney donors with diabetes. We retrospectively investigated 241 living kidney donors who underwent nephrectomy at Jichi Medical University Hospital between January 2000 and December 2015. Donors with a follow-up period of less than 1 year were excluded. The remaining donors were divided into a diabetic group and a non-diabetic group. Their clinical parameters before donation and renal prognosis after donation were compared. Of the 241 donors, 16 were excluded due to their follow-up period being less than 1 year. Of the remaining 225 donors, 14 were diabetic and 211 were non-diabetic. There were no significant differences in variables at pre-donation. The median follow-up period was 4.3 (1.5-10.7) and 4.6 (1.0-13.0) years in kidney donors with and without diabetes, respectively. At the end of follow-up, the estimated glomerular filtration rate was 51.7 ± 7.1 ml/min/1.73 m 2 in the diabetic group and 52.1 ± 12.2 ml/min/1.73 m 2 (p = 0.906) in the non-diabetic group; urine albumin excretion was 9.5 (2-251) mg/day (or mg/g creatinine) in the diabetic group and 6 (0-626) mg/day (or mg/g creatinine) in the non-diabetic group (p = 0.130); and urine protein excretion was 0.079 (0-0.41) g/day in the diabetic group and 0.051 (0-3.7) g/day in the non-diabetic group (p = 0.455). There were no significant differences in short-term renal prognosis between kidney donors with and without diabetes.

Kinetic modeling of electron transfer reactions in photosystem I complexes of various structures with substituted quinone acceptors.

PubMed

Milanovsky, Georgy E; Petrova, Anastasia A; Cherepanov, Dmitry A; Semenov, Alexey Yu

2017-09-01

The reduction kinetics of the photo-oxidized primary electron donor P 700 in photosystem I (PS I) complexes from cyanobacteria Synechocystis sp. PCC 6803 were analyzed within the kinetic model, which considers electron transfer (ET) reactions between P 700 , secondary quinone acceptor A 1 , iron-sulfur clusters and external electron donor and acceptors - methylviologen (MV), 2,3-dichloro-naphthoquinone (Cl 2 NQ) and oxygen. PS I complexes containing various quinones in the A 1 -binding site (phylloquinone PhQ, plastoquinone-9 PQ and Cl 2 NQ) as well as F X -core complexes, depleted of terminal iron-sulfur F A /F B clusters, were studied. The acceleration of charge recombination in F X -core complexes by PhQ/PQ substitution indicates that backward ET from the iron-sulfur clusters involves quinone in the A 1 -binding site. The kinetic parameters of ET reactions were obtained by global fitting of the P 700 + reduction with the kinetic model. The free energy gap ΔG 0 between F X and F A /F B clusters was estimated as -130 meV. The driving force of ET from A 1 to F X was determined as -50 and -220 meV for PhQ in the A and B cofactor branches, respectively. For PQ in A 1A -site, this reaction was found to be endergonic (ΔG 0  = +75 meV). The interaction of PS I with external acceptors was quantitatively described in terms of Michaelis-Menten kinetics. The second-order rate constants of ET from F A /F B , F X and Cl 2 NQ in the A 1 -site of PS I to external acceptors were estimated. The side production of superoxide radical in the A 1 -site by oxygen reduction via the Mehler reaction might comprise ≥0.3% of the total electron flow in PS I.

Recipient-Matching of Passenger Leukocytes Prolongs Survival of Donor Lung Allografts in Miniature Swine

PubMed Central

Madariaga, Maria Lucia L.; Michel, Sebastian G.; La Muraglia, Glenn M.; Sihag, Smita; Leonard, David A.; Farkash, Evan A.; Colvin, Robert B.; Cetrulo, Curtis L.; Huang, Christene A.; Sachs, David H.; Madsen, Joren C.; Allan, James S.

2014-01-01

Background Allograft rejection continues to be a vexing problem in clinical lung transplantation, and the role played by passenger leukocytes in the rejection or acceptance of an organ is unclear. Here we tested whether recipient-matching of donor graft passenger leukocytes would impact graft survival in a preclinical model of orthotopic left lung transplantation. Methods In the experimental group (Group 1), donor lungs were obtained from chimeric swine, in which the passenger leukocytes (but not the parenchyma) were MHC-matched to the recipients (n=3). In the control group (Group 2), both the donor parenchyma and the passenger leukocytes were MHC-mismatched to the recipients (n = 3). Results Lungs harvested from swine previously rendered chimeric by hematopoietic stem cell transplantation using recipient-type cells showed a high degree of passenger leukocyte chimerism by immunohistochemistry and flow cytometry. The chimeric lungs containing passenger leukocytes matched to the lung recipient (Group 1) survived on average 107 days (range 80–156). Control lung allografts (Group 2) survived on average 45 days (range 29–64; p<0.05). Conclusion Our data indicate that recipient-matching of passenger leukocytes significantly prolongs lung allograft survival. PMID:25757217

The Prolonged Life-Span of Alveolar Macrophages

PubMed Central

Murphy, Jaime; Summer, Ross; Wilson, Andrew A.; Kotton, Darrell N.; Fine, Alan

2008-01-01

To further examine the half-life of alveolar macrophages, chimeric CD 45.2 mice were generated through bone marrow transplantation of donor CD 45.1 cells. Before administration of donor cells, recipient mice were divided into two cohorts: the first cohort received total body irradiation; the second cohort also received irradiation—however, the thorax, head, and upper extremities were shielded with lead. Flow cytometric analysis was then performed on blood, peritoneal, and bronchoalveolar lavage cells over time to quantify engraftment. The data generated for the unshielded cohort of mice revealed a macrophage half-life of 30 days. In the shielded cohort, however, we found that by 8 months there was negligible replacement of recipient alveolar macrophages by donor cells, despite reconstitution of the blood and peritoneum by donor bone marrow. Consistent with these findings, the mean fluorescent intensity of alveolar macrophages remained stable over a 4-week period after in vivo PKH26 dye loading. Together, these data show that previous alveolar macrophage half-life studies were confounded by the fact that they did not account for the toxic effects of irradiation conditioning regimens, and demonstrate that the bone marrow does not significantly contribute to the alveolar macrophage compartment during steady-state conditions. PMID:18192503

Comparison of lactate, formate, and propionate as hydrogen donors for the reductive dehalogenation of trichloroethene in a continuous-flow column.

PubMed

Azizian, Mohammad F; Marshall, Ian P G; Behrens, Sebastian; Spormann, Alfred M; Semprini, Lewis

2010-04-01

A continuous-flow column study was conducted to analyze the reductive dehalogenation of trichloroethene (TCE) with aquifer material with high content of iron oxides. The column was bioaugmented with the Point Mugu (PM) culture, which is a mixed microbial enrichment culture capable of completely transforming TCE to ethene (ETH). We determined whether lactate, formate, or propionate fermentation resulted in more effective dehalogenation. Reductive dehalogenation, fermentation, and sulfate, Fe(III), and Mn(IV) reduction were all exhibited within the column. Different steady-states of dehalogenation were achieved based on the concentration of substrates added, with effective transformation to ETH obtained when ample electron donor equivalents were provided. Most of the metabolic reducing equivalents were channeled to sulfate, Fe(III), and Mn(IV) reduction. When similar electron reducing equivalents were added, the most effective dehalogenation was achieved with formate, with 14% of the electron equivalents going towards dehalogenation reactions, compared to 6.5% for lactate and 9.6% for propionate. Effective dehalogenation was maintained over 1000 days of column operation. Over 90% of electron equivalents added could be accounted for by the different electron accepting processes in the column, with 50% associated with soluble and precipitated Fe(II) and Mn(II). Bulk Fe(III) and Mn(IV) reduction was rather associated with lactate and propionate addition than formate addition. Sulfate reduction was a competing electron acceptor reaction with all three electron donors. DNA was extracted from solid coupon samples obtained during the course of the experiment and analyzed using 16S rRNA gene clone libraries and quantitative PCR. Lactate and propionate addition resulted in a significant increase in Geobacter, Spirochaetes, and Desulfitobacterium phylotypes relative to "Dehalococcoides" when compared to formate addition. Results from the molecular biological analyses support chemical observations that a greater percentage of the electron donor addition was channeled to Fe(III) reduction when lactate and propionate were added compared to formate, and formate was more effective than lactate in supporting dehalogenation. The results demonstrate the importance of electron donor selection and competing electron acceptor reactions when implementing reductive dehalogenation remediation technologies. Published by Elsevier B.V.

Comparison of lactate, formate, and propionate as hydrogen donors for the reductive dehalogenation of trichloroethene in a continuous-flow column

NASA Astrophysics Data System (ADS)

Azizian, Mohammad F.; Marshall, Ian P. G.; Behrens, Sebastian; Spormann, Alfred M.; Semprini, Lewis

2010-04-01

A continuous-flow column study was conducted to analyze the reductive dehalogenation of trichloroethene (TCE) with aquifer material with high content of iron oxides. The column was bioaugmented with the Point Mugu (PM) culture, which is a mixed microbial enrichment culture capable of completely transforming TCE to ethene (ETH). We determined whether lactate, formate, or propionate fermentation resulted in more effective dehalogenation. Reductive dehalogenation, fermentation, and sulfate, Fe(III), and Mn(IV) reduction were all exhibited within the column. Different steady-states of dehalogenation were achieved based on the concentration of substrates added, with effective transformation to ETH obtained when ample electron donor equivalents were provided. Most of the metabolic reducing equivalents were channeled to sulfate, Fe(III), and Mn(IV) reduction. When similar electron reducing equivalents were added, the most effective dehalogenation was achieved with formate, with 14% of the electron equivalents going towards dehalogenation reactions, compared to 6.5% for lactate and 9.6% for propionate. Effective dehalogenation was maintained over 1000 days of column operation. Over 90% of electron equivalents added could be accounted for by the different electron accepting processes in the column, with 50% associated with soluble and precipitated Fe(II) and Mn(II). Bulk Fe(III) and Mn(IV) reduction was rather associated with lactate and propionate addition than formate addition. Sulfate reduction was a competing electron acceptor reaction with all three electron donors. DNA was extracted from solid coupon samples obtained during the course of the experiment and analyzed using 16S rRNA gene clone libraries and quantitative PCR. Lactate and propionate addition resulted in a significant increase in Geobacter, Spirochaetes, and Desulfitobacterium phylotypes relative to " Dehalococcoides" when compared to formate addition. Results from the molecular biological analyses support chemical observations that a greater percentage of the electron donor addition was channeled to Fe(III) reduction when lactate and propionate were added compared to formate, and formate was more effective than lactate in supporting dehalogenation. The results demonstrate the importance of electron donor selection and competing electron acceptor reactions when implementing reductive dehalogenation remediation technologies.

Transmission Bottleneck Size Estimation from Pathogen Deep-Sequencing Data, with an Application to Human Influenza A Virus.

PubMed

Sobel Leonard, Ashley; Weissman, Daniel B; Greenbaum, Benjamin; Ghedin, Elodie; Koelle, Katia

2017-07-15

The bottleneck governing infectious disease transmission describes the size of the pathogen population transferred from the donor to the recipient host. Accurate quantification of the bottleneck size is particularly important for rapidly evolving pathogens such as influenza virus, as narrow bottlenecks reduce the amount of transferred viral genetic diversity and, thus, may decrease the rate of viral adaptation. Previous studies have estimated bottleneck sizes governing viral transmission by using statistical analyses of variants identified in pathogen sequencing data. These analyses, however, did not account for variant calling thresholds and stochastic viral replication dynamics within recipient hosts. Because these factors can skew bottleneck size estimates, we introduce a new method for inferring bottleneck sizes that accounts for these factors. Through the use of a simulated data set, we first show that our method, based on beta-binomial sampling, accurately recovers transmission bottleneck sizes, whereas other methods fail to do so. We then apply our method to a data set of influenza A virus (IAV) infections for which viral deep-sequencing data from transmission pairs are available. We find that the IAV transmission bottleneck size estimates in this study are highly variable across transmission pairs, while the mean bottleneck size of 196 virions is consistent with a previous estimate for this data set. Furthermore, regression analysis shows a positive association between estimated bottleneck size and donor infection severity, as measured by temperature. These results support findings from experimental transmission studies showing that bottleneck sizes across transmission events can be variable and influenced in part by epidemiological factors. IMPORTANCE The transmission bottleneck size describes the size of the pathogen population transferred from the donor to the recipient host and may affect the rate of pathogen adaptation within host populations. Recent advances in sequencing technology have enabled bottleneck size estimation from pathogen genetic data, although there is not yet a consistency in the statistical methods used. Here, we introduce a new approach to infer the bottleneck size that accounts for variant identification protocols and noise during pathogen replication. We show that failing to account for these factors leads to an underestimation of bottleneck sizes. We apply this method to an existing data set of human influenza virus infections, showing that transmission is governed by a loose, but highly variable, transmission bottleneck whose size is positively associated with the severity of infection of the donor. Beyond advancing our understanding of influenza virus transmission, we hope that this work will provide a standardized statistical approach for bottleneck size estimation for viral pathogens. Copyright © 2017 Sobel Leonard et al.

The role of extracorporeal membrane oxygenation in patients after irreversible cardiac arrest as potential organ donors

PubMed Central

Puślecki, Mateusz; Zieliński, Marcin; Mandecki, Michał; Ligowski, Marcin; Stefaniak, Sebastian; Dąbrowski, Marek; Karczewski, Marek; Gąsiorowski, Łukasz; Sip, Maciej; Dąbrowska, Agata; Telec, Wojciech; Perek, Bartłomiej; Jemielity, Marek

2017-01-01

The number of people waiting for a kidney or liver transplant is growing systematically. Due to the latest advances in transplantation, persons after irreversible cardiac arrest and confirmation of death have become potential organ donors. It is estimated that they may increase the number of donations by more than 40%. However, without good organization and communication between pre-hospital care providers, emergency departments, intensive care units and transplantation units, it is almost impossible to save the organs of potential donors in good condition. Various systems, including extracorporeal membrane oxygenation (ECMO), supporting perfusion of organs for transplantation play a key role. In 2016 the “ECMO for Greater Poland” program was established. Although its main goal is to improve the survival rate of patients suffering from life-threatening cardiopulmonary conditions, one of its branches aims to increase the donation rate in patients with irreversible cardiac arrest. In this review, the role of ECMO in the latter group as the potential organ donors is presented. PMID:29354178

The effect of repeated blood donations on the iron status of male Saudi blood donors

PubMed Central

Abdullah, Saleh M.

2011-01-01

Background. Regular blood donation can lead to iron deficiency. Screening donors’ serum ferritin levels at the time of first donation and subsequently once every year is a very rational way to pick up iron deficiency in a voluntary blood donor population. The aim of this study was to determine the effect of blood donation and the prevalence of erythropoiesis with iron deficiency (sideropenia) in Saudi male blood donors. Materials and methods. The study was prospectively conducted, between December 2008 and March 2009, on 182 male native Saudi blood donors at King Fahd Central Hospital in Jazan region, Saudi Arabia. Each donor gave 450±50 mL of whole blood. Following the donation, samples were removed into 2.5 mL EDTA tubes for measurement of mean cell volume (MCV) and mean corpuscular haemoglobin (MCH) and into 7.5 mL plain tubes for estimation of iron and serum ferritin concentrations. The blood donors were divided into five groups, according to the number of donations they had given in the preceding 3 years. The blood donors in group I were first-time donors, with no previous history of blood donation. Group II donors had donated once in the last 3 years. Subjects in groups III, IV and V had donated more than once in the preceding 3 years and were considered regular donors. Results. The mean serum iron was significantly higher among subjects with no previous history of blood donation (group I) than among regular donors who had donated twice or more. The difference in serum ferritin concentration was statistically significant (p<0.05) when comparing regular donors in group III (72.4 μg/L), group IV (67.4 μg/L) and group V (26.2 μg/L) with first-time blood donors (131.4 μg/L). In contrast, the difference in the concentration of serum ferritin between subjects in group II (98.9 μg/L), who had donated once in the last 3 years, and in first-time blood donors (131.4 μg/L) was not statistically significant (p<0.131). None of the group I donors suffered from iron deficiency, whereas 2.8% of the donors who had donated between two to five times had iron deficiency. The prevalence of erythropoiesis with iron deficiency in regular blood donors was 4.3%. Conclusion. The results of this study show that an increase in the number of donations results in an increase in the frequency of depleted iron stores and subsequently in erythropoiesis with iron deficiency, although the level of haemoglobin remained acceptable for blood donation. This result may indicate the need to review the guidelines on acceptance of donors. PMID:21084007

The reproducibility and predictive value on outcome of renal biopsies from expanded criteria donors.

PubMed

Azancot, M Antonieta; Moreso, Francesc; Salcedo, Maite; Cantarell, Carme; Perello, Manel; Torres, Irina B; Montero, Angeles; Trilla, Enric; Sellarés, Joana; Morote, Joan; Seron, Daniel

2014-05-01

Reproducibility and predictive value on outcome are the main criteria to evaluate the utility of histological scores. Here we analyze the reproducibility of donor biopsy assessment by different on-call pathologists and the retrospective evaluation by a single renal pathologist blinded to clinical outcomes. We also evaluate the predictive value on graft outcome of both evaluations. A biopsy was performed in donors with any of the following: age≥55 years, hypertension, diabetes, creatinine>1.5 mg/dl, or stroke. Glomerulosclerosis, interstitial fibrosis, tubular atrophy, intimal thickening, and arteriolar hyalinosis evaluated according to the Banff criteria were added to obtain a chronic score. Biopsies were classified as mild (≥3), intermediate (4-5), or advanced (6-7) damage, and unacceptable (≥8) for transplantation of 127 kidneys biopsied. Weighted κ value between both readings was 0.41 (95% CI: 0.28-0.54). Evaluation of biopsies by the renal pathologist was significantly and independently associated with estimated 12-month glomerular filtration rate and a significant composite outcome variable, including death-censored graft survival and time to reach an estimated glomerular filtration rate<30 ml/min per 1.73 m2. Thus, there was no association between readings of on-call pathologists and outcome. The lack of association between histological scores obtained by the on-call pathologists and graft outcome suggests that a specific training on renal pathology is recommended to optimize the use of kidneys retrieved from expanded criteria donors.

Hepatitis E risks: pigs or blood-that is the question.

PubMed

Tedder, Richard S; Ijaz, Samreen; Kitchen, Alan; Ushiro-Lumb, Ines; Tettmar, Kate I; Hewitt, Patricia; Andrews, Nick

2017-02-01

Infection with hepatitis E virus (HEV) Genotype 3 is recognized as a food-borne zoonosis in developed countries where it usually causes a mild self-limited acute hepatitis. It may cause a persistent infection in the immunosuppressed human that can progress to cirrhosis. To protect the patient from transfusion-acquired HEV infection, steps have been taken in the United Kingdom to provide for at-risk patients only components from donors screened for HEV viremia. This strategy does not protect from dietary exposure and calls into question estimation of relative risk between blood transfusion and diet. Using data on HEV viremia, component exposure, residual plasma volume, and resulting transmission, the dose of virus administered and subsequent transmission rates were determined and used to populate a model that can infer the relationship between blood and dietary exposure. The annual attack rate of a population, defined as seroconversion, provides an estimate of the risk of receiving a component containing HEV from a viremic donor. The lowest viral dose that resulted in infection was 2 × 10 4 IUs and 55% of components containing this dose transmitted infection. The transfusion risk of infection only exceeds the annual dietary risk when more than 13 individual donor components are transfused. For many solid organ transplant patients dietary exposure far exceeds the risk of transfusion from unscreened donors. It is only in the immunosuppressed patient requiring extensive blood component support that transfusion risk dominates. This understanding should inform policy decisions on HEV RNA screening of blood donations. © 2017 AABB.

The Predicted Cross Value for Genetic Introgression of Multiple Alleles

PubMed Central

Han, Ye; Cameron, John N.; Wang, Lizhi; Beavis, William D.

2017-01-01

We consider the plant genetic improvement challenge of introgressing multiple alleles from a homozygous donor to a recipient. First, we frame the project as an algorithmic process that can be mathematically formulated. We then introduce a novel metric for selecting breeding parents that we refer to as the predicted cross value (PCV). Unlike estimated breeding values, which represent predictions of general combining ability, the PCV predicts specific combining ability. The PCV takes estimates of recombination frequencies as an input vector and calculates the probability that a pair of parents will produce a gamete with desirable alleles at all specified loci. We compared the PCV approach with existing estimated-breeding-value approaches in two simulation experiments, in which 7 and 20 desirable alleles were to be introgressed from a donor line into a recipient line. Results suggest that the PCV is more efficient and effective for multi-allelic trait introgression. We also discuss how operations research can be used for other crop genetic improvement projects and suggest several future research directions. PMID:28122824

Polarizability and binding energy of a shallow donor in spherical quantum dot-quantum well (QD-QW)

NASA Astrophysics Data System (ADS)

Rahmani, K.; Chrafih, Y.; M’Zred, S.; Janati, S.; Zorkani, I.; Jorio, A.; Mmadi, A.

2018-03-01

The polarizability and the binding energy is estimated for a shallow donor confined to move in inhomogeneous quantum dots (CdS/HgS/CdS). In this work, the Hass variational method within the effective mass approximation in used in the case of an infinitely deep well. The polarizability and the binding energy depend on the inner and the outer radius of the QDQW, also it depends strongly on the donor position. It’s found that the stark effect is more important when the impurity is located at the center of the (QDQW) and becomes less important when the donor moves toward the extremities of the spherical layer. When the electric field increases, the binding energy and the polarizability decreases. Its effects is more pronounced when the impurity is placed on the center of the spherical layer and decrease when the donor move toward extremities of this spherical layer. We have demonstrated the existence of a critical value {≤ft( {{{{R_1}} \\over {{R_2}}}} \\right)cri} which can be used to distinguish the tree dimension confinement from the spherical surface confinement and it’s may be important for the nanofabrication techniques.

Chemiluminescent Detection for Estimating Relative Copy Numbers of Porcine Endogenous Retrovirus Proviruses from Chinese Minipigs Based on Magnetic Nanoparticles.

PubMed

Yang, Haowen; Liu, Ming; Zhou, Bingcong; Deng, Yan; He, Nongyue; Jiang, Hesheng; Guo, Yafen; Lan, Ganqiu; Jiang, Qinyang; Yang, Xiurong; Li, Zhiyang

2016-06-01

Chinese Bama minipigs could be potential donors for the supply of xenografts because they are genetically stable, highly inbred, and inexpensive. However, porcine endogenous retrovirus (PERV) is commonly integrated in pig genomes and could cause a cross-species infection by xenotransplantation. For screening out the pigs with low copy numbers of PERV proviruses, we have developed a novel semiquantitative analysis approach based on magnetic nanoparticles (MNPs) and chemiluminescence (CL) for estimating relative copy numbers (RCNs) of PERV proviruses in Chinese Bama minipigs. The CL intensities of PERV proviruses and the housekeeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were respectively determined with this method, and the RCNs of PERV proviruses were calculated by the equation: RCN of PERV provirus = CL intensity of PERV provirus/CL intensity of GAPDH. The results showed that PERVs were integrated in the genomes of Bama minipigs at different copy numbers, and the copy numbers of PERV-C subtype were greatly low. Two Bama minipigs with low copy numbers of PERV proviruses were detected out and could be considered as xenograft donor candidates. Although only semiquantitation can be achieved, this approach has potential for screening out safe and suitable pig donors for xenotransplantation.

Parameter regionalisation methods for a semi-distributed rainfall-runoff model: application to a Northern Apennine region

NASA Astrophysics Data System (ADS)

Neri, Mattia; Toth, Elena

2017-04-01

The study presents the implementation of different regionalisation approaches for the transfer of model parameters from similar and/or neighbouring gauged basin to an ungauged catchment, and in particular it uses a semi-distributed continuously-simulating conceptual rainfall-runoff model for simulating daily streamflows. The case study refers to a set of Apennine catchments (in the Emilia-Romagna region, Italy), that, given the spatial proximity, are assumed to belong to the same hydrologically homogeneous region and are used, alternatively, as donors and regionalised basins. The model is a semi-distributed version of the HBV model (TUWien model) in which the catchment is divided in zones of different altitude that contribute separately to the total outlet flow. The model includes a snow module, whose application in the Apennine area has been, so far, very limited, even if snow accumulation and melting phenomena do have an important role in the study basins. Two methods, both widely applied in the recent literature, are applied for regionalising the model: i) "parameters averaging", where each parameter is obtained as a weighted mean of the parameters obtained, through calibration, on the donor catchments ii) "output averaging", where the model is run over the ungauged basin using the entire set of parameters of each donor basin and the simulated outputs are then averaged. In the first approach, the parameters are regionalised independently from each other, in the second one, instead, the correlation among the parameters is maintained. Since the model is a semi-distributed one, where each elevation zone contributes separately, the study proposes to test also a modified version of the second approach ("output averaging"), where each zone is considered as an autonomous entity, whose parameters are transposed to the ungauged sub-basin corresponding to the same elevation zone. The study explores also the choice of the weights to be used for averaging the parameters (in the "parameters averaging" approach) or for averaging the simulated streamflow (in the "output averaging" approach): in particular, weights are estimated as a function of the similarity/distance of the ungauged basin/zone to the donors, on the basis of a set of geo-morphological catchment descriptors. The predictive accuracy of the different regionalisation methods is finally assessed by jack-knife cross-validation against the observed daily runoff for all the study catchments.

Use of instantaneous streamflow measurements to improve regression estimates of index flow for the summer month of lowest streamflow in Michigan

USGS Publications Warehouse

Holtschlag, David J.

2011-01-01

In Michigan, index flow Q50 is a streamflow characteristic defined as the minimum of median flows for July, August, and September. The state of Michigan uses index flow estimates to help regulate large (greater than 100,000 gallons per day) water withdrawals to prevent adverse effects on characteristic fish populations. At sites where long-term streamgages are located, index flows are computed directly from continuous streamflow records as GageQ50. In an earlier study, a multiple-regression equation was developed to estimate index flows IndxQ50 at ungaged sites. The index equation explains about 94 percent of the variability of index flows at 147 (index) streamgages by use of six explanatory variables describing soil type, aquifer transmissivity, land cover, and precipitation characteristics. This report extends the results of the previous study, by use of Monte Carlo simulations, to evaluate alternative flow estimators, DiscQ50, IntgQ50, SiteQ50, and AugmQ50. The Monte Carlo simulations treated each of the available index streamgages, in turn, as a miscellaneous site where streamflow conditions are described by one or more instantaneous measurements of flow. In the simulations, instantaneous flows were approximated by daily mean flows at the corresponding site. All estimators use information that can be obtained from instantaneous flow measurements and contemporaneous daily mean flow data from nearby long-term streamgages. The efficacy of these estimators was evaluated over a set of measurement intensities in which the number of simulated instantaneous flow measurements ranged from 1 to 100 at a site. The discrete measurement estimator DiscQ50 is based on a simple linear regression developed between information on daily mean flows at five or more streamgages near the miscellaneous site and their corresponding GageQ50 index flows. The regression relation then was used to compute a DiscQ50 estimate at the miscellaneous site by use of the simulated instantaneous flow measurement. This process was repeated to develop a set of DiscQ50 estimates for all simulated instantaneous measurements, a weighted DiscQ50 estimate was formed from this set. Results indicated that the expected value of this weighted estimate was more precise than the IndxQ50 estimate for all measurement intensities evaluated. The integrated index-flow estimator, IntgQ50, was formed by computing a weighted average of the index estimate IndxQ50 and the DiscQ50 estimate. Results indicated that the IntgQ50 estimator was more precise than the DiscQ50 estimator at low measurement intensities of one to two measurements. At greater measurement intensities, the precision of the IntgQ50 estimator converges to the DiscQ50 estimator. Neither the DiscQ50 nor the IntgQ50 estimators provided site-specific estimates. In particular, although expected values of DiscQ50 and IntgQ50 estimates converge with increasing measurement intensity, they do not necessarily converge to the site-specific value of Q50. The site estimator of flow, SiteQ50, was developed to facilitate this convergence at higher measurement intensities. This is accomplished by use of the median of simulated instantaneous flow values for each measurement intensity level. A weighted estimate of the median and information associated with the IntgQ50 estimate was used to form the SiteQ50 estimate. Initial simulations indicate that the SiteQ50 estimator generally has greater precision than the IntgQ50 estimator at measurement intensities greater than 3, however, additional analysis is needed to identify streamflow conditions under which instantaneous measurements will produce estimates that generally converge to the index flows. A preliminary augmented index regression equation was developed, which contains the index regression estimate and two additional variables associated with base-flow recession characteristics. When these recession variables were estimated as the medians of recession parameters compute

Preventing disease transmission by deceased tissue donors by testing blood for viral nucleic acid.

PubMed

Strong, D Michael; Nelson, Karen; Pierce, Marge; Stramer, Susan L

2005-01-01

Nucleic acid testing (NAT) has reduced the risk of transmitting infectious disease through blood transfusion. Currently NAT for HIV-1 and HCV are FDA licensed and performed by nearly all blood collection facilities, but HBV NAT is performed under an investigational study protocol. Residual risk estimates indicate that NAT could potentially reduce disease transmission through transplanted tissue. However, tissue donor samples obtained post-mortem have the potential to produce an invalid NAT result due to inhibition of amplification reactions by hemolysis and other factors. The studies reported here summarize the development of protocols to allow NAT of deceased donor samples with reduced rates of invalid results. Using these protocols, inventories from two tissue centers were tested with greater than 99% of samples producing a valid test result.

Distance-dependent energy transfer between indole and anthracene moieties in Langmuir Blodgett films

NASA Astrophysics Data System (ADS)

Saha, D. C.; Bhattacharjee, D.; Misra, T. N.

1998-09-01

1,2-Diphenyl indole (DPI) and 9,10-diphenyl anthracene (DPA) are non-amphiphilic molecules but form excellent LB films when mixed with stearic acid (SA). Spectroscopic investigations of these films indicate formation of aggregates of DPI and DPA in the mixed LB films. DPA has been used as the quencher of the fluorescence of the DPI donor. Distance-dependent energy transfer between donor and acceptor monolayers in the LB film, where they can be precisely separated by inert spacers of stearic acid layers of varied thickness, is shown to satisfy Khun's quadratic equation. This suggests that the donor excitations are delocalized. The large critical transfer distance estimated from the experimental results has been attributed to the formation of aggregates of the molecules in a LB monolayer.

Oxidation of humic substances supports denitrification reactions in agricultural soils.

NASA Astrophysics Data System (ADS)

van Trump, J. I.; Coates, J. D.

2007-12-01

Humic substances (HS) are a ubiquitous, recalcitrant, and diverse class of compounds arising from degradation and condensation of plant and microbial biopolymers. Many bacteria oxidize hydroquinones within humic substances to their quinone analogs, providing electrons for respiratory processes such as nitrate reduction. Microbial hydroquinone oxidation contributes to the redox state of HS and supports denitrification, which may be of import to agricultural soils where nitrate retention is critical and HS are prevalent. Most probable number counts were performed on soils collected from a Nebraska farm, with the model humic hydroquinone 2,6- anthrahydroquinone disulfonate (AHDS) serving as an electron donor and nitrate as the electron acceptor. Results indicated that AHDS oxidizing, nitrate reducing bacteria were present in soils from bluegrass fields (104 cells/g) and aspen groves (106 cells/g), as well as in plots of corn (106 cells/g), and soybean treated (106 cells/g) and un-treated (105 cells/g) with pig slurry. These results demonstrate that microorganisms participating in the proposed metabolism are prevalent within agricultural soils. Upflow glass columns were constructed, containing a support matrix of glass beads amended with 10% w/w soil from the corn plot previously mentioned. All columns were subjected to a continual flow of phosphate-buffered water amended with sodium nitrate. Above the point source for nitrate injection, phosphate-buffered water containing electron donor treatments were continually injected. The impacts of electron donor treatments (no donor, oxidized HS, reduced HS, and acetate) on denitrification and other geochemical parameters were observed. Column studies were able to resolve effects of electron donor treatment both spatially as a function of distance from the injection point source, and temporally, as a function of time of donor treatment. Four sample ports in each column were routinely analyzed for concentrations of nitrate, nitrite, Fe(II), and humic-born hydroquinones. All data were analyzed with respect to dilution factors obtained through analysis of a conservative bromide tracer present in electron donor medium. Addition of oxidized HS, reduced HS, and acetate all resulted in significant loss of nitrate from the columns. Significant nitrite accumulation was not observed. Of all the electron donor treatments, reduced HS, enriched for hydroquinone-containing functional moieties, supported the greatest degree of denitrification. The participation of excess hydroquinones in denitrification accounted for approximately 104% of the difference in nitrate reduction between reduced and oxidized HS treatments. This electron balance allowed for assignment of respiratory activity due to hydroquinone oxidation, rather than degradation of humic substances or associated electron-donating compounds. These results suggest that denitrification reactions catalyzed by microbial oxidation of reduced HS may be prevalent in agricultural soils. Likewise, these results demonstrate for the first time that respiratory behavior due to hydroquinone oxidation, as well as impact upon local geochemistry, can be analyzed in complex flow-through model systems.

Timing of distant flap pedicle division using xenon 133 clearance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snelling, C.F.; Poomee, A.; Sutherland, J.B.

1980-09-01

Clearance of intradermally injected xenon 133 was used to measure blood flow in distant flaps in humans with the donor pedicle temporarily clamped just prior to division. All 18 flaps with a blood flow of 0.5 ml per 100 gm of tissue per minute or more survived completely after separation. Of 7 with lesser flow, 3 underwent marginal necrosis adjacent to the line of division and 4 survived entirely. Xenon 133 washout does permit quantitative evaluation of blood flow, and since it is a clean isotope, it appears superior to sodium 24 and technetium 99m, which have been used inmore » a similar manner. The test is proposed as an adjunct to clinical judgment in timing pedicle division.« less

A comparison of the effects of oral vs. intravenous hydration on subclinical acute kidney injury in living kidney donors: a protocol of a randomised controlled trial.

PubMed

Mackinnon, Shona; Aitken, Emma; Ghita, Ryan; Clancy, Marc

2017-01-19

Optimal treatment for established renal failure is living donor kidney transplantation. However this pathway exposes healthy individuals to significant reduction in nephron mass via major surgical procedure. Laparoscopic donor nephrectomy is now the most common method for live donor transplantation, reducing both donor post-operative pain and recovery time. However this procedure exposes kidneys to additional haemodynamic stresses. It has been suggested that donor hydration-particularly the use of preoperative intravenous fluids-may counteract these stresses, reducing subclinical acute kidney injury and ultimately improving long-term renal function. This may be important in both preservation of donor renal function and recipient graft longevity. A prospective single-centre single-blinded randomized controlled trial will be carried out to determine the effects of donor preoperative intravenous fluids. The primary outcome is donor subclinical acute kidney injury (defined as plasma NGAL, >153 ng/ml) on day 1 postoperatively. Secondary outcomes include intraoperative haemodynamics, recipient subclinical acute kidney injury, perioperative complications and donor sleep quality. Donors will be randomised into two groups: the intervention group will receive active pre-hydration consisting of three litres of intravenous Hartmann's solution between midnight and 8 am before morning kidney donation, while the control group will not receive this. Both groups will receive unlimited oral fluids until midnight, as is routine. Plasma NGAL will be measured at pre-specified perioperative time points, intraoperative haemodynamic data will be collected using non-invasive cardiac output monitoring and clinical notes will be used to obtain demographic and clinical data. The researcher will be blinded to the donor fluid hydration status. Blinded statistical analysis will be performed on an intention-to-treat basis. A prospective power calculation estimates a required sample size of 86 patients. This study will provide important data, as there is currently little evidence about the use of donor preoperative fluids in laparoscopic nephrectomy. It is hoped that the results obtained will guide future clinical practice. This study has been approved by the West of Scotland Research Ethics Committee 3 (reference no. 14/WS/1160, 27 January 2015) and is registered with the International Standard Randomised Controlled Trial Number Register (reference no. ISRCTN10199225 , 20 April 2015).

Relative safety of pooled whole blood-derived versus single-donor (apheresis) platelets in the United States: a systematic review of disparate risks.

PubMed

Vamvakas, Eleftherios C

2009-12-01

Risks of transfusion-transmitted infections (TTIs), transfusion-associated sepsis (TAS), and transfusion-related acute lung injury (TRALI) were compared between pooled whole blood-derived (PWBD) and single-donor platelets (PLTs) transfused in the United States. The literature was searched for estimates of the risk of TTIs and TAS and of the effect on bacterial contamination of PLTs of process improvements, bacterial culture, and surrogate methods to detect bacteria. Seven studies published between January 2005 and December 2008 and comparing bacterial contamination frequency between PWBD and single-donor PLTs after implementing bacterial culture testing of both components were subjected to meta-analysis. The three retrieved studies diagnosing TRALI based on the 2004 consensus definition in settings transfusing both PWBD and single-donor PLTs were not amenable to meta-analysis and were assessed qualitatively. Under a best-case scenario, if 100% (from the current 12.5%) of PLT doses were provided as PWBD PLTs, the number of additional transmissions of human immunodeficiency virus, hepatitis C virus, hepatitis B virus, bacteria, or a novel pathogen annually could be 1.2, 1.3, 9.0, 105.3, or 69.2 to 252.6, respectively. Compared with single-donor PLTs, US PLT pools of five concentrates have a 5.6-fold higher risk of bacterial contamination (summary odds ratio, 5.58; 95% confidence interval, 2.60-11.98; p < 0.05). The three studies that diagnosed TRALI based on the consensus definition did not demonstrate a difference in risk between PWBD and single-donor PLTs. TTIs and TAS determine the relative safety of PWBD versus single-donor PLTs. The available limited data do not support a higher risk of TRALI from single-donor (compared with PWBD) PLTs.

Evaluation of positive and false-positive results in syphilis screening of blood donors in Rio de Janeiro, Brazil.

PubMed

Sandes, V S; Silva, S G C; Motta, I J F; Velarde, L G C; de Castilho, S R

2017-06-01

We propose to analyse the positive and false-positive results of treponemal and nontreponemal tests in blood donors from Brazil and to evaluate possible factors associated with the results of treponemal tests. Treponemal tests have been used widely for syphilis screening in blood banks. The introduction of these tests in donor screening has caused an impact and a loss of donors who need to be assessed. This was a retrospective cross-sectional study of syphilis screening and confirmatory test results of blood donors that were obtained before and after adopting a chemiluminescent immunoassay (CLIA). A comparative analysis was performed using a second sample drawn from positive donors. The possible factors associated with CLIA-positive or CLIA-false-positive results were investigated in a subgroup. Statistical tests were used to compare the proportions and adjusted estimates of association. The reactivity rate increased from 1·01% (N = 28 158) to 2·66% (N = 25 577) after introducing the new test. Among Venereal Disease Research Laboratory (VDRL)- and CLIA-confirmed results, the false-positive rates were 40·5% (N = 180) and 37·4% (N = 359), respectively (P = 0·5266). Older donors (OR = 1·04; P = 0·0010) and donors with lower education levels (OR = 6·59; P = 0·0029) were associated with a higher risk of positivity for syphilis. CLIA represents an improvement in blood bank serological screening. However, its use in a healthy population appears to result in high rates of false positives. Identifying which characteristics can predict false positives, however, remains a challenge. © 2017 British Blood Transfusion Society.

[Association between the viruses of the acquired immunodeficiency syndrome and the hepatitis C virus among young blood donors in Kinshasa: Retrospective analysis of 10 years].

PubMed

Sumbu, B M M; Longo-Mbenza, B; Ahuka-Mundeke, S; Muwonga, J M; Mvumbi-Lelo, G; Maphana, H M; Kayembe Nzongola-Nkasu, D; Kalumbu, F M

2018-02-01

The screening of anti-Human Immunodeficiency Virus antibodies is mandatory in every blood donor admitted to the Blood Bank of Kinshasa University Clinics since 1984. However, no compiled data are available to date. The objective of this study was to establish the trend, prevalence, viral co-infections, and determinants of Human Immunodeficiency anti-Virus serology in blood donors admitted between 2003-2006 and 2008-2013. A retrospective analysis was carried out at University Kinshasa Clinics, using blood donors' records during 2003-2006 and 2008-2013. The prevalence of the human immunodeficiency virus per year, age, sex and type of blood donors were estimated. Independent predictors of human immunodeficiency virus seropositivity were also identified. Out of 26,341 blood donors, 2.2% (n=576/26,341) were seropositive for Human Immunodeficiency Virus. Age<25 years (OR=1.7; 95% CI: 1.4-2; P<0.0001) and Hepatitis C virus seropositivity (OR=3; 95% CI; 1.8-4.9; P<0.001) emerged as independent predictors of Human Immunodeficiency Virus seropositivity. This study shows a strong association between the Human Immunodeficiency Virus and hepatitis C and younger age respectively. Further studies are needed to ensure safety of Blood donation in Democratic Republic of Congo. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Determination of Acidity in Donor Milk.

PubMed

Escuder-Vieco, Diana; Vázquez-Román, Sara; Sánchez-Pallás, Juan; Ureta-Velasco, Noelia; Mosqueda-Peña, Rocío; Pallás-Alonso, Carmen Rosa

2016-11-01

There is no uniformity among milk banks on milk acceptance criteria. The acidity obtained by the Dornic titration technique is a widely used quality control in donor milk. However, there are no comparative data with other acidity-measuring techniques, such as the pH meter. The objective of this study was to assess the correlation between the Dornic technique and the pH measure to determine the pH cutoff corresponding to the Dornic degree limit value used as a reference for donor milk quality control. Fifty-two human milk samples were obtained from 48 donors. Acidity was measured using the Dornic method and pH meter in triplicate. Statistical data analysis to estimate significant correlations between variables was carried out. The Dornic acidity value that led to rejecting donor milk was ≥ 8 Dornic degrees (°D). In the evaluated sample size, Dornic acidity measure and pH values showed a statistically significant negative correlation (τ = -0.780; P = .000). A pH value of 6.57 corresponds to 8°D and of 7.12 to 4°D. Donor milk with a pH over 6.57 may be accepted for subsequent processing in the milk bank. Moreover, the pH measurement seems to be more useful due to certain advantages over the Dornic method, such as objectivity, accuracy, standardization, the lack of chemical reagents required, and the fact that it does not destroy the milk sample.

Prevalence of human T-cell lymphotropic virus types 1 and 2 in blood donors of the Caruaru Blood Center (Hemope)

PubMed Central

de Lima, Waleska Mayara Gomes; Esteves, Fabrício Andrade Martins; Torres, Maria do Carmo Morais Rodrigues; Pires, Edna Suely Feitosa

2013-01-01

Background There is difficulty in gathering data on the prevalence of human T-cell lymphotropic virus in blood donors as confirmatory testing is not mandatory in Brazil. This suggests there may be an underreporting of the prevalence. Objective To estimate the prevalence of human T-cell lymphotropic virus types 1 and 2 in donors of a blood bank in Caruaru, Brazil. Methods This was an observational, epidemiological, descriptive, longitudinal and retrospective study with information about the serology of donors of the Caruaru Blood Center, Fundação de Hematologia e Hemoterapia de Pernambuco (Hemope) from May 2006 to December 2010. The data were analyzed using the Excel 2010 computer program (Microsoft Office®). Results Of 61,881 donors, 60 (0.096%) individuals were identified as potential carriers of human T-cell lymphotropic virus types 1 and 2. Of these, 28 (0.045%) were positive and 32 (0.051%) had inconclusive results in the serological screening. Forty-five (0.072%) were retested; 17 were positive (0.027%) and 3 inconclusive (0.005%). After confirmatory tests, 8 were positive (0.013%). Six (75%) of the confirmed cases were women. Conclusion Epidemiological surveys like this are very important in order to create campaigns to attract donors and reduce the costs of laboratory tests. PMID:24106445

Applications of plasma sources for nitric oxide medicine

NASA Astrophysics Data System (ADS)

Vasilets, Victor; Shekhter, Anatoly; Pekshev, Alexander

2013-09-01

Nitric oxide (NO) has important roles in the function of many tissues and organs. Wound healing processes are always accompanying by the increase of nitric oxide concentration in wound tissue. These facts suggest a possible therapeutic use of various NO donors for the acceleration of the wound healing and treatment of other diseases. Our previous studies indicated that gaseous NO flow produced by air-plasma generators acts beneficially on the wound healing. This beneficial effect could be caused by the mechanism involving peroxynitrite as an intermediate. As a result of mobilization of various antioxidant reactions more endogenous NO molecules become available as signaling molecules. to regulate the metabolic processes in wound tissue. In this paper different air plasma sources generated therapeutic concentrations of NO are discussed. The concentration of NO and other therapeutically important gas products are estimated by thermodynamic simulation. Synergy effects of NO with other plasma components are discussed as a factor enhancing therapeutic results. Some new medical application of plasma devices are presented. Advanced Plasma Therapies Inc.

Modeling gene flow distribution within conventional fields and development of a simplified sampling method to quantify adventitious GM contents in maize

PubMed Central

Melé, Enric; Nadal, Anna; Messeguer, Joaquima; Melé-Messeguer, Marina; Palaudelmàs, Montserrat; Peñas, Gisela; Piferrer, Xavier; Capellades, Gemma; Serra, Joan; Pla, Maria

2015-01-01

Genetically modified (GM) crops have been commercially grown for two decades. GM maize is one of 3 species with the highest acreage and specific events. Many countries established a mandatory labeling of products containing GM material, with thresholds for adventitious presence, to support consumers’ freedom of choice. In consequence, coexistence systems need to be introduced to facilitate commercial culture of GM and non-GM crops in the same agricultural area. On modeling adventitious GM cross-pollination distribution within maize fields, we deduced a simple equation to estimate overall GM contents (%GM) of conventional fields, irrespective of its shape and size, and with no previous information on possible GM pollen donor fields. A sampling strategy was designed and experimentally validated in 19 agricultural fields. With 9 samples, %GM quantification requires just one analytical GM determination while identification of the pollen source needs 9 additional analyses. A decision support tool is provided. PMID:26596213

Comparison of matched sibling donors versus unrelated donors in allogeneic stem cell transplantation for primary refractory acute myeloid leukemia: a study on behalf of the Acute Leukemia Working Party of the EBMT.

PubMed

Brissot, Eolia; Labopin, Myriam; Stelljes, Matthias; Ehninger, Gerhard; Schwerdtfeger, Rainer; Finke, Jürgen; Kolb, Hans-Jochem; Ganser, Arnold; Schäfer-Eckart, Kerstin; Zander, Axel R; Bunjes, Donald; Mielke, Stephan; Bethge, Wolfgang A; Milpied, Noël; Kalhs, Peter; Blau, Igor-Woflgang; Kröger, Nicolaus; Vitek, Antonin; Gramatzki, Martin; Holler, Ernst; Schmid, Christoph; Esteve, Jordi; Mohty, Mohamad; Nagler, Arnon

2017-06-24

Primary refractory acute myeloid leukemia (PRF-AML) is associated with a dismal prognosis. Allogeneic stem cell transplantation (HSCT) in active disease is an alternative therapeutic strategy. The increased availability of unrelated donors together with the significant reduction in transplant-related mortality in recent years have opened the possibility for transplantation to a larger number of patients with PRF-AML. Moreover, transplant from unrelated donors may be associated with stronger graft-mediated anti-leukemic effect in comparison to transplantations from HLA-matched sibling donor, which may be of importance in the setting of PRF-AML. The current study aimed to address the issue of HSCT for PRF-AML and to compare the outcomes of HSCT from matched sibling donors (n = 660) versus unrelated donors (n = 381), for patients with PRF-AML between 2000 and 2013. The Kaplan-Meier estimator, the cumulative incidence function, and Cox proportional hazards regression models were used where appropriate. HSCT provide patients with PRF-AML a 2-year leukemia-free survival and overall survival of about 25 and 30%, respectively. In multivariate analysis, two predictive factors, cytogenetics and time from diagnosis to transplant, were associated with lower leukemia-free survival, whereas Karnofsky performance status at transplant ≥90% was associated with better leukemia-free survival (LFS). Concerning relapse incidence, cytogenetics and time from diagnosis to transplant were associated with increased relapse. Reduced intensity conditioning regimen was the only factor associated with lower non-relapse mortality. HSCT was able to rescue about one quarter of the patients with PRF-AML. The donor type did not have any impact on PRF patients' outcomes. In contrast, time to transplant was a major prognostic factor for LFS. For patients with PRF-AML who do not have a matched sibling donor, HSCT from an unrelated donor is a suitable option, and therefore, initiation of an early search for allocating a suitable donor is indicated.

Centrally Determined Standardization of Flow Cytometry Methods Reduces Interlaboratory Variation in a Prospective Multicenter Study.

PubMed

Westera, Liset; van Viegen, Tanja; Jeyarajah, Jenny; Azad, Azar; Bilsborough, Janine; van den Brink, Gijs R; Cremer, Jonathan; Danese, Silvio; D'Haens, Geert; Eckmann, Lars; Faubion, William; Filice, Melissa; Korf, Hannelie; McGovern, Dermot; Panes, Julian; Salas, Azucena; Sandborn, William J; Silverberg, Mark S; Smith, Michelle I; Vermeire, Severine; Vetrano, Stefania; Shackelton, Lisa M; Stitt, Larry; Jairath, Vipul; Levesque, Barrett G; Spencer, David M; Feagan, Brian G; Vande Casteele, Niels

2017-11-02

Flow cytometry (FC) aids in characterization of cellular and molecular factors involved in pathologic immune responses. Although FC has potential to facilitate early drug development in inflammatory bowel disease, interlaboratory variability limits its use in multicenter trials. Standardization of methods may address this limitation. We compared variability in FC-aided quantitation of T-cell responses across international laboratories using three analytical strategies. Peripheral blood mononuclear cells (PBMCs) were isolated from three healthy donors, stimulated with phorbol 12-myristate 13-acetate and ionomycin at a central laboratory, fixed, frozen, and shipped to seven international laboratories. Permeabilization and staining was performed in triplicate at each laboratory using a common protocol and centrally provided reagents. Gating was performed using local gating with a local strategy (LGLS), local gating with a central strategy (LGCS), and central gating (CG). Median cell percentages were calculated across triplicates and donors, and reported for each condition and strategy. The coefficient of variation (CV) was calculated across laboratories. Between-strategy comparisons were made using a two-way analysis of variance adjusting for donor. Mean interlaboratory CV ranged from 1.8 to 102.1% depending on cell population and gating strategy (LGLS, 4.4-102.1%; LGCS, 10.9-65.6%; CG, 1.8-20.9%). Mean interlaboratory CV differed significantly across strategies and was consistently lower with CG. Central gating was the only strategy with mean CVs consistently lower than 25%, which is a proposed standard for pharmacodynamic and exploratory biomarker assays.

Flow cytometric characterization of culture expanded multipotent mesenchymal stromal cells (MSCs) from horse adipose tissue: towards the definition of minimal stemness criteria.

PubMed

Pascucci, L; Curina, G; Mercati, F; Marini, C; Dall'Aglio, C; Paternesi, B; Ceccarelli, P

2011-12-15

In the last decades, multipotent mesenchymal progenitor cells have been isolated from many adult tissues of different species. The International Society for Cellular Therapy (ISCT) has recently established that multipotent mesenchymal stromal cells (MSCs) is the currently recommended designation. In this study, we used flow cytometry to evaluate the expression of several molecules related to stemness (CD90, CD44, CD73 and STRO-1) in undifferentiated, early-passaged MSCs isolated from adipose tissue of four donor horses (AdMSCs). The four populations unanimously expressed high levels of CD90 and CD44. On the contrary, they were unexpectedly negative to CD73. A small percentage of the cells, finally, showed the expression of STRO-1. This last result might be due to the existence of a small subpopulation of STRO-1+ cells or to a poor cross-reactivity of the antibody. A remarkable donor-to-donor consistency and reproducibility of these findings was demonstrated. The data presented herein support the idea that equine AdMSCs may be easily isolated and selected by adherence to tissue culture plastic and exhibit a surface profile characterized by some peculiar differences in comparison to those described in other species. Continued characterization of these cells will help to clarify several aspects of their biology and may ultimately enable the isolation of specific, purified subpopulations. Copyright © 2011 Elsevier B.V. All rights reserved.

Aid and good governance: Examining aggregate unintended effects of aid.

PubMed

Dijkstra, Geske

2018-06-01

Although donors generally aim to improve governance in recipient countries by various means, critics claim that the aggregate effect of large aid flows is the deterioration of governance. Aid is said to weaken domestic accountability, sustain authoritarian regimes, increase political instability, weaken government capacities, and increase corruption. Conducting a systematic search in Web of Science, this paper reviews the empirical evidence for these unintended aggregate effects of aid on the political, administrative, and judicial dimensions of good governance. It finds that the negative effects of aid on governance are much exaggerated. The aggregate effect of aid on democracy has become more positive after the Cold War, and the effect of aid on government capacity and on reducing corruption has also improved over time. Furthermore, most studies show a positive effect of aid on political stability. These findings imply that donor intentions matter: donors that are serious about their intended effects on governance are able to mitigate the possible negative unintended effects of their aid. Copyright © 2017 Elsevier Ltd. All rights reserved.

Propeller Flap for Complex Distal Leg Reconstruction: A Versatile Alternative when Reverse Sural Artery Flap is Not Feasible.

PubMed

Ademola, Samuel A; Michael, Afieharo I; Oladeji, Femi J; Mbaya, Kefas M; Oyewole, O

2015-01-01

Reverse sural artery fasciocutaneous flap has become a workhorse for the reconstruction of distal leg soft tissue defects. When its use is not feasible, perforator-based propeller flap offers a better, easier, faster, and cheaper alternative to free flap. We present our experience with two men both aged 34 years who sustained Gustilo 3B injuries from gunshot. The donor area for reversed sural artery flap was involved in the injuries. They had early debridement, external fixation, and wound coverage with perforator-based propeller flaps. The donor sites were covered with skin graft. All flaps survived. There were minor wound edge ulcers due to the pressure of positioning that did not affect flap survival and the ulcers healed with conservative management. Perforator-based propeller flap is a versatile armamentarium for reconstruction of soft tissue defects of the distal leg in resource-constrained settings, especially when the donor area for a reverse flow sural flap artery is involved in the injury.

8/8 and 10/10 high-resolution match rate for the be the match unrelated donor registry.

PubMed

Dehn, Jason; Buck, Kelly; Maiers, Martin; Confer, Dennis; Hartzman, Robert; Kollman, Craig; Schmidt, Alexander H; Yang, Soo Young; Setterholm, Michelle

2015-01-01

The National Marrow Donor Program's Be The Match Registry(®) facilitates the worldwide utilization of unrelated donor (URD) grafts for patients in need of a hematopoietic cell transplantation. In this study, we estimate the URD match rate for patients of White (WH), Hispanic (HIS), Asian/Pacific Islander (API), and African American/Black (AFA) race and ethnic groups. We chose 1344 URD at random as "pseudo-patients" (PP) to estimate the likelihood of finding an 8/8 or 10/10 high-resolution HLA-A,-B,-C,-DRB1 (and -DQB1) matched URD. Searches were conducted in the Be The Match Registry database for each PP at 2 time points: 2009 and 2012. URD who were a potential match for a PP by low/intermediate resolution were HLA typed by sequence-based typing to resolve the matching status. The 8/8 match rate for WH PP improved from 68% in 2009 to 72% in 2012. Corresponding match rates were 41% to 44% for HIS, 44% to 46% for API, and 27% to 30% for AFA, for 2009 and 2012, respectively. The 2012 10/10 match rates were 67% for WH, 38% for HIS, 41% for API, and 23% for AFA. These results provide baseline 8/8 and 10/10 match rate estimates by race for patients seeking an URD. Copyright © 2015 American Society for Blood and Marrow Transplantation. All rights reserved.

Genetic analysis of oocyte and embryo production traits in Guzerá breed donors and their associations with age at first calving.

PubMed

Perez, B C; Peixoto, M G C D; Bruneli, F T; Ramos, P V B; Balieiro, J C C

2016-04-26

The objective of this study was to estimate variance components for oocyte and embryo production traits in Guzerá breed female donors, and investigate their associations with age at first calving (AFC). The traits analyzed were the number of viable oocytes (NOV), the number of grade I oocytes (NGI), the number of cleaved embryos (NCLV), and viable embryos produced (NEMB), and the percentages of viable oocytes (POV), grade I oocytes (PGI), cleaved embryos (PCLV), and viable embryos (PEMB). Data were obtained from 5173 ovary puncture and in vitro fertilization (IVF) sessions using 1080 Guzerá female donors of different ages, occurred from March 2005 to July 2013. Variables were log-transformed (logeX+1) prior to analysis. (Co)variance components were estimated by restricted maximum likelihood (REML), using one- and two-trait animal models. Permanent environment and IVF sire (father of the embryos) random effects were included. Estimated heritabilities for NOV, NGI, NCLV, NEMB, POV, PGI, PCLV, and PEMB were 0.19, 0.08, 0.16, 0.14, 0.04, 0.03, 0.01, and 0.07, respectively. Repeatabilities for count traits (NOV, NGI, NCLV, and NEMB) varied from 0.14 and 0.32, higher than estimated for percentage traits (POV, PGI, PCLV, and PEMB), which varied from 0.01 to 0.08. Selection for NOV may be more appropriate in breeding programs than selection for NEMB, because of its strong genetic correlation (0.68) with NEMB and its greater time- and cost-effectiveness. AFC was only weakly associated with the oocyte and embryo production traits, which indicates that there would be no effect on AFC when selecting for these traits.

Funding AIDS programmes in the era of shared responsibility: an analysis of domestic spending in 12 low-income and middle-income countries.

PubMed

Resch, Stephen; Ryckman, Theresa; Hecht, Robert

2015-01-01

As the incomes of many AIDS-burdened countries grow and donors' budgets for helping to fight the disease tighten, national governments and external funding partners increasingly face the following question: what is the capacity of countries that are highly affected by AIDS to finance their responses from domestic sources, and how might this affect the level of donor support? In this study, we attempt to answer this question. We propose metrics to estimate domestic AIDS financing, using methods related to national prioritisation of health spending, disease burden, and economic growth. We apply these metrics to 12 countries in sub-Saharan Africa with a high prevalence of HIV/AIDS, generating scenarios of possible future domestic expenditure. We compare the results with total AIDS financing requirements to calculate the size of the resulting funding gaps and implications for donors. Nearly all 12 countries studied fall short of the proposed expenditure benchmarks. If they met these benchmarks fully, domestic spending on AIDS would increase by 2·5 times, from US$2·1 billion to $5·1 billion annually, covering 64% of estimated future funding requirements and leaving a gap of around a third of the total $7·9 billion needed. Although upper-middle-income countries, such as Botswana, Namibia, and South Africa, would become financially self-reliant, lower-income countries, such as Mozambique and Ethiopia, would remain heavily dependent on donor funds. The proposed metrics could be useful to stimulate further analysis and discussion around domestic spending on AIDS and corresponding donor contributions, and to structure financial agreements between recipient country governments and donors. Coupled with improved resource tracking, such metrics could enhance transparency and accountability for efficient use of money and maximise the effect of available funding to prevent HIV infections and save lives. US Centers for Disease Control and Prevention. Copyright © 2015 Hecht et al. Open Access article distributed under the terms of CC BY-NC-ND. Published by .. All rights reserved.

Transfusion-transmitted infectious diseases in Argentina, 1995 through 1997.

PubMed

Schmuñis, G A; Zicker, F; Segura, E L; del Pozo, A E

2000-09-01

Assessment of the safety of the blood supply, the quality of screening procedures, and the risk of transfusion transmission of infectious diseases in any country can be estimated by reviewing the records of blood donations and screening procedures and the prevalence of serologic markers of infectious diseases. Information on blood donors, particularly the number of screened donors, and on the prevalence of serologic markers of infectious diseases was available from Argentina for 1995 through 1997. This information permitted the estimation of the risks and costs of preventing transfusion transmission of infectious diseases within the country during this period. Screening coverage was higher in the private sector. The proportion of donors screened for HIV increased from 84.52 percent in 1995 to 97.97 percent in 1997; in the same period, serologic screening for HbsAg increased from 83.71 percent to 98.48 percent; that for HCV from 69. 92 percent to 97.83 percent; and that for syphilis from 87.94 percent to 98.71 percent. One hundred percent of donors were screened for Trypanosoma cruzi throughout the period. The overall prevalence of HIV per year varied from 2.42 to 3.36 per 1,000 donors; that of HBV, from 5.80 to 9.76 per 1,000; of HCV, from 7.39 to 16.61 per 1,000; and of syphilis, from 5.25 to 7.65 per 1,000. The overall prevalence of antibodies to T. cruzi ranged from 36.53 to 49.20 per 1,000 donors. The overall index of the spread of infectious viral disease through blood transfusion decreased from 47. 74 per 10,000 donations in 1995 to 4.75 per 10,000 in 1997. The ratio of acquired infections to donations improved from 1:209 to 1:2, 102 during the same period. The risk of T. cruzi infection from 1995 through 1997 was, in theory, nil, given the 100-percent screening. The greatest threat to the quality of the blood supply throughout the period studied was HCV. The status of the blood supply in Argentina improved steadily from 1995 to 1997, as shown by the increase in screening coverage.

Mitigation of the threat posed to transfusion by donors traveling to Zika-affected areas: a Canadian risk-based approach.

PubMed

Germain, Marc; Delage, Gilles; O'Brien, Sheila F; Grégoire, Yves; Fearon, Margaret; Devine, Dana

2017-10-01

The recent spread of the Zika virus to the Americas and the recognition that it can cause severe disease in the developing fetus has prompted the adoption of measures to mitigate the risk that this virus might pose to transfusion safety. In nonendemic countries, the risk to transfusion results from donors traveling to an endemic region. Canada implemented a 21-day temporary deferral for prospective donors who traveled to such regions. We present the rationale for this policy, including a quantitative risk assessment supported by a Monte Carlo simulation. The model considered the following parameters, each with specified values and ranges: the probability that a donor recently returned from a Zika-endemic region, the duration of travel to this region, the daily risk of acquiring Zika while in an endemic region, and the incubation and viremic periods. We ran the simulation 20 times, each with 10 million iterations. In the absence of any travel deferral, 32 donors (range, 20-46 donors) would be able to donate while still being at risk of transmitting Zika, corresponding to a rate of 1:312,500 (range, 1:217,000 to 1:500,000). None of these donors would be viremic beyond 21 days after returning from their travel, with a risk estimated at less than 1:200,000,000. A 21-day temporary travel deferral offers an extremely wide margin of safety for the possible transmission of Zika by a donation obtained from someone who recently returned from a country where the virus is circulating. © 2017 AABB.

Effect of N-Acetylcysteine Pretreatment of Deceased Organ Donors on Renal Allograft Function: A Randomized Controlled Trial

PubMed Central

Orban, Jean-Christophe; Quintard, Hervé; Cassuto, Elisabeth; Jambou, Patrick; Samat-Long, Corine; Ichai, Carole

2015-01-01

Background Antioxidant donor pretreatment is one of the pharmacologic strategy proposed to prevent renal ischemia-reperfusion injuries and delayed graft function (DGF). The aim of the study was to investigate whether a donor pretreatment with N-acetylcysteine (NAC) reduces the incidence of DGF in adult human kidney transplant recipients. Methods In this randomized, open-label, monocenter trial, 160 deceased heart-beating donors were allowed to perform 236 renal transplantations from September 2005 to December 2010. Donors were randomized to receive, in a single-blind controlled fashion, 600 mg of intravenous NAC 1 hr before and 2 hr after cerebral angiography performed to confirm brain death. Primary endpoint was DGF defined by the need for at least one dialysis session within the first week or a serum creatinine level greater than 200 μmol/L at day 7 after kidney transplantation. Results The incidence of DGF was similar between donors pretreated with or without NAC (39/118; 33% vs. 30/118; 25.4%; P = 0.19). Requirement for at least one dialysis session was not different between the NAC and No NAC groups (17/118; 14.4% vs. 14/118; 11.8%, P = 0.56). The two groups had comparable serum creatinine levels, estimated glomerular filtration rates, and daily urine output at days 1, 7, 15, and 30 after kidney transplantation as well as at hospital discharge. No difference in recipient mortality nor in 1-year kidney graft survival was observed. Conclusion Donor pretreatment with NAC does not improve delayed graft function after kidney transplantation. PMID:25250647

The cost-effectiveness of predonation screening for transfusion transmissible infections using rapid test kits in a hospital-based blood transfusion centre.

PubMed

Dosunmu, Adedoyin Owolabi; Akinbami, Akinsegun Abduljaleel; Ismail, Ayobami Kamal; Olaiya, Modupe Adebimpe; Uche, Ebele Ifeyinwa; Aile, Igbinoba Kingsley

2017-01-01

Blood transfusion practice emphasises safety, efficacy and appropriate use. These require cost-effective programme management. This study focused on the cost of screening for transfusion transmissible infections (TTI). This was a 1 year (2016) analysis of screening in a hospital-based transfusion centre. The cost of screening all blood donors by ELISA was compared to the cost of serial screening starting from rapid kit, taking into account, the estimated cost of blood bags prevented from discard after ELISA screening (attributable cost). The cost of voluntary donor drive plus cost of ELISA screening was compared with the present cost of screening. A total of 5591 donors were screened for HIV, hepatitis B and C using the rapid kit, 291 donors were deferred (5.2%). A total of 5300 units were further screened by ELISA. A total of 435 blood units (8.2%) were discarded due to TTI positivity. TTI positivity rate was 12.98%. Only 2.36% were voluntary donors and among these 9.1% were TTI positive. The attributable cost of serial screening was 55,653.5 USD while that of screening by ELISA only was 55,910 USD. The attributable cost of rapid screening for only hepatitis B and then ELISA was 53,313.9 USD taking into consideration that 187 blood units would be prevented from undue discard. This analysis demonstrated that with proper donor selection, rapid screening for hepatitis B virus only before ELISA screening is more cost-effective. This will also reduce the waiting time for donors and counselling if HIV positive.

The live donor assessment tool: a psychosocial assessment tool for live organ donors.

PubMed

Iacoviello, Brian M; Shenoy, Akhil; Braoude, Jenna; Jennings, Tiane; Vaidya, Swapna; Brouwer, Julianna; Haydel, Brandy; Arroyo, Hansel; Thakur, Devendra; Leinwand, Joseph; Rudow, Dianne LaPointe

2015-01-01

Psychosocial evaluation is an important part of the live organ donor evaluation process, yet it is not standardized across institutions, and although tools exist for the psychosocial evaluation of organ recipients, none exist to assess donors. We set out to develop a semistructured psychosocial evaluation tool (the Live Donor Assessment Tool, LDAT) to assess potential live organ donors and to conduct preliminary analyses of the tool's reliability and validity. Review of the literature on the psychosocial variables associated with treatment adherence, quality of life, live organ donation outcome, and resilience, as well as review of the procedures for psychosocial evaluation at our center and other centers around the country, identified 9 domains to address; these domains were distilled into several items each, in collaboration with colleagues at transplant centers across the country, for a total of 29 items. Four raters were trained to use the LDAT, and they retrospectively scored 99 psychosocial evaluations conducted on live organ donor candidates. Reliability of the LDAT was assessed by calculating the internal consistency of the items in the scale and interrater reliability between raters; validity was estimated by comparing LDAT scores between those with a "positive" evaluation outcome and "negative" outcome. The LDAT was found to have good internal consistency, inter-rater reliability, and showed signs of validity: LDAT scores differentiated the positive vs. negative outcome groups. The LDAT demonstrated good reliability and validity, but future research on the LDAT and the ability to implement the LDAT prospectively is warranted. Copyright © 2015 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

Geographic determinants of access to pediatric deceased donor kidney transplantation.

PubMed

Reese, Peter P; Hwang, Hojun; Potluri, Vishnu; Abt, Peter L; Shults, Justine; Amaral, Sandra

2014-04-01

Children receive priority in the allocation of deceased donor kidneys for transplantation in the United States, but because allocation begins locally, geographic differences in population and organ supply may enable variation in pediatric access to transplantation. We assembled a cohort of 3764 individual listings for pediatric kidney transplantation in 2005-2010. For each donor service area, we assigned a category of short (<180 days), medium (181-270 days), or long (>270 days) median waiting time and calculated the ratio of pediatric-quality kidneys to pediatric candidates and the percentage of these kidneys locally diverted to adults. We used multivariable Cox regression analyses to examine the association between donor service area characteristics and time to deceased donor kidney transplantation. The Kaplan-Meier estimate of median waiting time to transplantation was 284 days (95% confidence interval, 263 to 300 days) and varied from 14 to 1313 days across donor service areas. Overall, 29% of pediatric-quality kidneys were locally diverted to adults. Compared with areas with short waiting times, areas with long waiting times had a lower ratio of pediatric-quality kidneys to candidates (3.1 versus 5.9; P<0.001) and more diversions to adults (31% versus 27%; P<0.001). In multivariable regression, a lower kidney to candidate ratio remained associated with longer waiting time (hazard ratio, 0.56 for areas with <2:1 versus reference areas with ≥5:1 kidneys/candidates; P<0.01). Large geographic variation in waiting time for pediatric deceased donor kidney transplantation exists and is highly associated with local supply and demand factors. Future organ allocation policy should address this geographic inequity.

Explainable variation in renal transplant outcomes: a comparison of standard and expanded criteria donors.

PubMed

Gjertson, David W

2004-01-01

In 2002, OPTN/UNOS altered kidney allocation rules to allow patients to be listed separately to receive kidneys from expanded criteria donors (ECD). Our aim was to quantify the short- and long-term impacts of 21 prognostic factors on recipients of ECD as well as recipients of living (LD) and deceased standard criteria (SCD) donors. A factor's impact depends on both the risk and diversity of its effects. Using OPTN/UNOS Registry data from 1996-2003, we have analyzed kidney-only, adult-recipient grafts for factor effects among 35,878 LD, 47,941 SCD and 10,399 ECD transplants. During an early risk period, all 94,218 recipients were followed through one year, and, in the late risk period, 85,270 recipients whose grafts survived beyond one year were followed for 5 years post-transplant. Impact was measured by determining a factor's percentage of assignable variation in one- and 5-year graft failure rates. Scores for 21 factors were estimated via generalized logistic models, which contained a random component for transplant center. The assignable variation associated with a given factor was computed as the factor score variance multiplied by the square of the corresponding regression coefficient. Impacts were heterogeneous with regard to posttransplant period and donor type. The top 5 factors influencing one-year graft survival rates were as follows: * For LD grafts - pretransplant dialysis time (14% of the variation in short-term outcomes), recipient age (13%), body mass (12%), PRA (10%) and induction therapy (10%). * For SCD grafts - donor age (24%), recipient age (12%), pretransplant dialysis time (12%), HLA-DR matching (6%) and pretransplant medical condition (6%). * For ECD grafts - donor age (18%), pre-transplant dialysis time (10%), recipient age (10%), pretransplant medical condition (10%) and recipient body mass (6%). Ranking long-term outcomes demonstrated the following top 5 influential factors: * For LD grafts - donor age (28% of the variation in long-term outcomes), recipient race (15%), age (15%), transplant year (13%) and recipient sex (11%). * For SCD grafts - donor age (35%), recipient race (23%), transplant year(15%), recipient sex (8%)and age (5%). * For ECD grafts - donor age (33%), recipient sex (20%), race (15%), transplant year (8%) and recipient's original disease (5%). Donor age was the dominant factor governing the survival rates among deceased donor kidney transplants. Advancing donor age was still the major risk factor for SCD transplant failure despite setting aside all donors 60 and up, and a large fraction of 50-59 year-old donors, from this group. Current ECD/SCD definitions warrant review and possible revision.

[Kidney transplantation epidemiology in France].

PubMed

Hiesse, Christian

2013-11-01

Kidney transplantation activity in France is among the most important worldwide: in 2011, 2976 transplants have been performed (47.5 per million population), and the number of patients living with a functional graft is estimated around 30,000, representing 44.7% of all patients (n = 67,270) treated for end-stage renal failure. However, the rate of preemptive kidney transplants remains very low, only 3.3% of incident patients starting renal replacement therapy. The analysis of demand showed a progressive increase in recent years, as demonstrated by the registration rate on the kidney transplantation waiting list, increasing by 5% yearly between 2006 and 2010, but with huge differences according to age categories and regional registration areas, reflecting discrepant appreciations in indications for kidney transplantation. The median waiting time between registration and transplantation increased progressively in recent years, reaching 22.3 months with considerable variations according to regional areas and transplantation teams. Kidney transplantation activity, while increasing continuously, is far to cover the rising demand, and inexorably patients accumulate on the waiting list (around 9000 patients were registered by January 2012). This situation is the consequence of insufficient organ procurement activity. The deceased organ procurement rate remained high: 1572 harvested donors in 2011 (24.1 per million population), but the proportion of older donors rose in recent years, to reach the rate of 26% of donors older than 65 years in 2011. The procurement activity of donors after cardiac arrest was reintroduced in 2006, but increased slowly: 65 transplants were performed in 2011 using kidney procured in non heart-beating donors. The living donor kidney transplantation activity has markedly increased recently: 302 living donor transplantations were performed in 2011, representing 10.1% of the kidney transplantations. Facing the predictable increase in the number of candidates, all efforts should be put together, by increasing the living donor transplantation activity and by supporting and promoting the deceased donor procurement activity. Copyright © 2013 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

The characterization of exosome from blood plasma of patients with colorectal cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yunusova, N. V., E-mail: Bochkarevanv@oncology.tomsk.ru; Siberian State Medical University, Moskovsky Trakt 2, Tomsk, 634050; Tamkovich, S. N., E-mail: s.tamk@niboch.nsc.ru

Exosomes are extracellular membrane structures involved in many physiological and pathological processes including cancerogenesis and metastasis. The clarification of the criteria for exosome isolating and identifying is the purpose of this study. Exosome samples from the plasma of patients with colorectal cancer and healthy donors were examined using transmission electron microscopy and flow cytometry in accordance with the minimum requirements of “International Society for Extracellular Vesicles”. The choice of the method for isolation of exosomes from the blood plasma by ultrafiltration and ultracentrifugation allowed obtaining highly purified samples of exosomes, in which all the structural components were clearly seen. Themore » results obtained with flow cytometry suggest that exosomes of blood plasma from patients with colorectal cancer can be produced by epithelial cells. Moreover, cells produce different types of exosomes, which correspond to different mechanisms in sorting macromolecules in the membrane of multivesicular bodies. Determination of significant differences in the expression of specific exosomal proteins from colorectal cancer patients compared to healthy donors suggests a high diagnostic potential significance of circulating exosomes.« less

Living donor liver transplantation for congenital absence of the portal vein.

PubMed

Sanada, Y; Mizuta, K; Kawano, Y; Egami, S; Hayashida, M; Wakiya, T; Mori, M; Hishikawa, S; Morishima, K; Fujiwara, T; Sakuma, Y; Hyodo, M; Yasuda, Y; Kobayashi, E; Kawarasaki, H

2009-12-01

The congenital absence of the portal vein (CAPV) is a rare venous malformation in which mesenteric venous blood drains directly into the systemic circulation. Liver transplantation (OLT) may be indicated for patients with symptomatic CAPV refractory to medical treatment, especially due to hyperammonemia, portosystemic encephalopathy, hepatopulmonary syndrome, or hepatic tumors. Because portal hypertension and collateral circulation do not occur with CAPV, significant splanchnic congestion may occur when the portocaval shunt is totally clamped during portal vein (PV) reconstruction in OLT. This phenomenon results in severe bowel edema and hemodynamic instability, which negatively impact the patient's condition and postoperative recovery. We have successfully reconstructed the PV in living donor liver transplantation (LDLT) using a venous interposition graft, which was anastomosed end-to-side to the portocaval shunt by a partial side-clamp, using a patent round ligament of the liver, which was anastomosed end-to-end to the graft PV with preservation of both the portal and caval blood flows. Owing to the differences in anatomy among patients, at LDLT for CAPV liver transplant surgeons should seek to preserve both portal and caval blood flows.

Section 17. Laparoscopic and minimal incisional donor hepatectomy.

PubMed

Choi, YoungRok; Yi, Nam-Joon; Lee, Kwang-Woong; Suh, Kyung-Suk

2014-04-27

Living donor hepatectomy is now a well-established surgical procedure. However, a large abdominal incision is still required, which results in a large permanent scar, especially for a right liver graft. This report reviews our techniques of minimally invasive or minimal incisional donor hepatectomy using a transverse incision.Twenty-five living donors underwent right hepatectomy with a transverse incision and 484 donors with a conventional incision between April 2007 and December 2012. Among the donors with a transverse incision, two cases were totally laparoscopic procedures using a hand-port device; 11 cases were laparoscopic-assisted hepatectomy (hybrid technique), and 14 cases were open procedures using a transverse incision without the aid of the laparoscopic technique. Currently, a hybrid method has been exclusively used because of the long operation time and surgical difficulty in totally laparoscopic hepatectomy and the exposure problems for the liver cephalic portion during the open technique using a transverse incision.All donors with a transverse incision were women except for one. Twenty-four of the grafts were right livers without middle hepatic vein (MHV) and one with MHV. The donors' mean BMI was 21.1 kg/m. The median operation time was 355 minutes, and the mean estimated blood loss was 346.1±247.3 mL (range, 70-1200). There was no intraoperative transfusion. These donors had 29 cases of grade I [14 pleural effusions (56%), 11 abdominal fluid collections (44%), 3 atelectasis (12%), 1bile leak (4%)], 1 case of grade II (1 pneumothorax) and two cases of grade III complications; two interventions were needed because of abdominal fluid collections by Clavien-Dindo classification. Meanwhile, donors with a conventional big incision, which included the Mercedes-Benz incision or an inverted L-shaped incision, had 433 cases of grade I, 19 cases of grade II and 18 cases of grade III complications. However, the liver enzymes and total bilirubin of all donors were normalized within 1 month, and they recovered fully. Additionally, in a survey inquiring about cosmetic outcomes with a numeric scale of 1 through 10 (1, Not confident; 10, Very confident), the transverse incision had more satisfactory scores compared to the conventional big incision (9.80 vs. 6.17, P=0.001). In conclusion, the hybrid technique can be safely performed in donor right hepatectomy, with a minimal transverse skin incision, resulting in a good cosmetic outcome.

On the Deficiencies of the Ferricinium-Ferrocene Redox Couple for Estimating Transfer Energies of Single Ions.

DTIC Science & Technology

1980-08-15

breakdown of the "ferrocene assumption" for estimating the transfer thermodynamics of single ions. I 4 Experimental Most solvents were Aldrich " Gold ...solvent "donor number" DN1 6 (Table I). A similar finding has been noted previously for monoatomic cations. 1 5 The small negative value of - Sc+) in water

Effect of sulfate on anaerobic reduction of nitrobenzene with acetate or propionate as an electron donor.

PubMed

Huang, Jingang; Wen, Yue; Ding, Ning; Xu, Yue; Zhou, Qi

2012-09-15

Sulfate is frequently found in wastewaters that contain nitrobenzene. To reveal the effect of sulfate on the reductive transformation of nitrobenzene to aniline--with acetate or propionate as potential electron donors in anaerobic systems--an acetate series (R1-R5) and a propionate series (R6-R10) were set up. Each of these was comprised of five laboratory-scale sequence batch reactors. The two series were amended with the same amount of nitrobenzene and electron donor electron equivalents, whereas with increasing sulfate concentrations. Results indicated that the presence of sulfate could depress nitrobenzene reduction. Such depression is linked to the inhibition of nitroreductase activity and/or the shift of electron flow. In the acetate series, although sulfate did not strongly compete with nitrobenzene for electron donors, noncompetitive inhibition of specific nitrobenzene reduction rates by sulfate was observed, with an inhibition constant of 0.40 mM. Propionate, which can produce intermediate H₂ as preferred reducing equivalent, is a more effective primary electron donor for nitrobenzene reduction as compared to acetate. In the propionate series, sulfate was found to be a preferential electron acceptor as compared to nitrobenzene, resulting in a quick depletion of propionate and then a likely termination of H₂-releasing under higher sulfate concentrations (R9 and R10). In such a situation, nitrobenzene reduction slowed down, occurring two-stage zero-order kinetics. Copyright © 2012 Elsevier Ltd. All rights reserved.

Using OCT to predict post-transplant renal function

NASA Astrophysics Data System (ADS)

Andrews, Peter M.; Chen, Yu; Wierwille, Jeremiah; Joh, Daniel; Alexandrov, Peter; Rogalsky, Derek; Moody, Patrick; Chen, Allen; Cooper, Matthew; Verbesey, Jennifer E.; Gong, Wei; Wang, Hsing-Wen

2013-03-01

The treatment of choice for patients with end-stage renal disease is kidney transplantation. However, acute tubular necrosis (ATN) induced by an ischemic insult (e.g., from prolonged ex vivo storage times, or non-heart beating cadavers) is a major factor limiting the availability of donor kidneys. In addition, ischemic induced ATN is a significant risk factor for eventual graft survival and can be difficult to discern from rejection. Currently, there are no rapid and reliable tests to determine ATN suffered by donor kidneys and whether or not donor kidneys might exhibit delayed graft function. OCT (optical coherence tomography) is a rapidly emerging imaging modality that can function as a type of "optical biopsy", providing cross-sectional images of tissue morphology in situ and in real-time. In a series of recent clinical trials, we evaluated the ability of OCT to image those features of the renal microstructure that are predictive of ATN. Specifically, we found that OCT could effectively image through the intact human renal capsule and determine the extent of acute tubular necrosis. We also found that Doppler based OCT (i.e., DOCT) revealed renal blood flow dynamics that is also reported to be a determiner of post-transplant renal function. This kind of information will allow transplant surgeons to make the most efficient use of available donor kidneys, eliminate the possible use of bad donor kidneys, provide a measure of expected post-transplant renal function, and allow better distinction between post-transplant immunological rejection and ischemic-induced acute renal failure.

Depolarized FRET (depolFRET) on the cell surface: FRET control by photoselection.

PubMed

Bene, László; Gogolák, Péter; Ungvári, Tamás; Bagdány, Miklós; Nagy, István; Damjanovich, László

2016-02-01

Sensitivity of FRET in hetero- and homo-FRET systems on the photoselected orientation distribution of donors has been proven by using polarized and depolarized light for excitation. FRET as well as donor and acceptor anisotropies have been simultaneously measured in a dual emission-polarization scheme realized in a conventional flow cytometer by using single laser excitation and applying fluorophore-conjugated mAbs against the MHCI and MHCII cell surface receptors. Depolarization of the originally polarized light have been achieved by using crystal depolarizers based on Cornu's principle, a quarter-wave plate for circular polarization, and a parallel beam splitter acting as a diagonal-polarizer for dual-polarization excitation. Simultaneous analysis of intensity-based FRET efficiency and acceptor depolarization equivocally report that depolarization of light may increase FRET in an amount depending on the acceptor-to-donor concentration ratio. Acceptor depolarization turned to be more sensitive to FRET than donor hyper-polarization and even than intensity-based FRET efficiency. It can be used as a sensitive tool for monitoring changes in the dynamics of the donor-acceptor pairs. The basic observations of FRET enhancement and increased acceptor depolarization obtained for hetero-FRET are paralleled by analog observations of homo-FRET enhancements under depolarized excitation. In terms of the orientation factor for FRET, the FRET enhancements on depolarization in the condition of the macroscopically isotropic orientation distributions such as those of the cell surface bound fluorophores report on the presence of local orientation mismatches of the donor and acceptor preventing the optimal FRET in the polarized case, which may be eliminated by the excitation depolarization. A theory of fluorescence anisotropy for depolarized excitation is also presented. Copyright © 2015 Elsevier B.V. All rights reserved.

Ex vivo lung perfusion to improve donor lung function and increase the number of organs available for transplantation.

PubMed

Valenza, Franco; Rosso, Lorenzo; Coppola, Silvia; Froio, Sara; Palleschi, Alessandro; Tosi, Davide; Mendogni, Paolo; Salice, Valentina; Ruggeri, Giulia M; Fumagalli, Jacopo; Villa, Alessandro; Nosotti, Mario; Santambrogio, Luigi; Gattinoni, Luciano

2014-06-01

This paper describes the initial clinical experience of ex vivo lung perfusion (EVLP) at the Fondazione Ca' Granda in Milan between January 2011 and May 2013. EVLP was considered if donor PaO2 /FiO2 was below 300 mmHg or if lung function was doubtful. Donors with massive lung contusion, aspiration, purulent secretions, pneumonia, or sepsis were excluded. EVLP was run with a low-flow, open atrium and low hematocrit technique. Thirty-five lung transplants from brain death donors were performed, seven of which after EVLP. EVLP donors were older (54 ± 9 years vs. 40 ± 15 years, EVLP versus Standard, P < 0.05), had lower PaO2 /FiO2 (264 ± 78 mmHg vs. 453 ± 119 mmHg, P < 0.05), and more chest X-ray abnormalities (P < 0.05). EVLP recipients were more often admitted to intensive care unit as urgent cases (57% vs. 18%, P = 0.05); lung allocation score at transplantation was higher (79 [40-84] vs. 39 [36-46], P < 0.05). After transplantation, primary graft dysfunction (PGD72 grade 3, 32% vs. 28%, EVLP versus Standard, P = 1), mortality at 30 days (0% vs. 0%, P = 1), and overall survival (71% vs. 86%, EVLP versus Standard P = 0.27) were not different between groups. EVLP enabled a 20% increase in available donor organs and resulted in successful transplants with lungs that would have otherwise been rejected (ClinicalTrials.gov number: NCT01967953). © 2014 The Authors. Transplant International published by John Wiley & Sons Ltd on behalf of Steunstichting ESOT.

Pollen-mediated gene flow in flax (Linum usitatissimum L.): can genetically engineered and organic flax coexist?

PubMed

Jhala, A J; Bhatt, H; Topinka, K; Hall, L M

2011-04-01

Coexistence allows growers and consumers the choice of producing or purchasing conventional or organic crops with known standards for adventitious presence of genetically engineered (GE) seed. Flax (Linum usitatissimum L.) is multipurpose oilseed crop in which product diversity and utility could be enhanced for industrial, nutraceutical and pharmaceutical markets through genetic engineering. If GE flax were released commercially, pollen-mediated gene flow will determine in part whether GE flax could coexist without compromising other markets. As a part of pre-commercialization risk assessment, we quantified pollen-mediated gene flow between two cultivars of flax. Field experiments were conducted at four locations during 2006 and 2007 in western Canada using a concentric donor (20 × 20 m) receptor (120 × 120 m) design. Gene flow was detected through the xenia effect of dominant alleles of high α-linolenic acid (ALA; 18:3(cisΔ9,12,15)) to the low ALA trait. Seeds were harvested from the pollen recipient plots up to a distance of 50 m in eight directions from the pollen donor. High ALA seeds were identified using a thiobarbituric acid test and served as a marker for gene flow. Binomial distribution and power analysis were used to predict the minimum number of seeds statistically required to detect the frequency of gene flow at specific α (confidence interval) and power (1-β) values. As a result of the low frequency of gene flow, approximately 4 million seeds were screened to derive accurate quantification. Frequency of gene flow was highest near the source: averaging 0.0185 at 0.1 m but declined rapidly with distance, 0.0013 and 0.00003 at 3 and 35 m, respectively. Gene flow was reduced to 50% (O₅₀) and 90% (O₉₀) between 0.85 to 2.64 m, and 5.68 to 17.56 m, respectively. No gene flow was detected at any site or year > 35 m distance from the pollen source, suggesting that frequency of gene flow was ≤ 0.00003 (P = 0.95). Although it is not possible to eliminate all adventitious presence caused by pollen-mediated gene flow, through harvest blending and the use of buffer zones between GE and conventional flax fields, it could be minimized. Managing other sources of adventitious presence including seed mixing and volunteer populations may be more problematic.

Counter-regulation of rejection activity against human liver grafts by donor PD-L1 and recipient PD-1 interaction.

PubMed

Shi, Xiao-Lei; Mancham, Shanta; Hansen, Bettina E; de Knegt, Robert J; de Jonge, Jeroen; van der Laan, Luc J W; Rivadeneira, Fernando; Metselaar, Herold J; Kwekkeboom, Jaap

2016-06-01

Co-inhibitory receptor-ligand interactions fine-tune immune responses by negatively regulating T cell functions. Our aim is to examine the involvement of co-inhibitory receptor-ligand pair PD-1/PD-L1 in regulating rejection after liver transplantation (LT) in humans. PD-L1/PD-1 expression in liver allograft was determined by immunohistochemistry or flow cytometry, and the effect of blockade was studied using graft-infiltrating T cells ex vivo. Five single nucleotide polymorphisms within PD-1 and PD-L1 genes were genotyped in 528 LT recipients and 410 donors, and associations with both early (⩽6months) and late (>6months) acute rejection were analyzed using Cox proportional-hazards regression model. The effect of PD-L1 rs4143815 on PD-L1 expression was analyzed using donor hepatic leukocytes. PD-L1 was expressed by hepatocytes, cholangiocytes and along the sinusoids in post-transplant liver allografts, and PD-1 was abundantly expressed on allograft-infiltrating T cells. PD-L1 blockade enhanced allogeneic proliferative responses of graft-infiltrating T cells. In the genetic association analysis, donor PD-L1 rs4143815 (CC/CG vs. GG; HR=0.230; p=0.002) and recipient PD-1 rs11568821 (AA/AG vs. GG; HR=3.739; p=0.004) were associated with acute rejection late after LT in multivariate analysis. Recipients carrying the PD-1 rs11568821 A allele who were transplanted with liver grafts of PD-L1 rs4143815 GG homozygous donors showed the highest risk for late acute rejection. PD-L1 rs4143815 is associated with differential PD-L1 expression on donor hepatic dendritic cells upon IFN-γ stimulation. Our data suggest that interplay between donor PD-L1 and recipient PD-1 counter-regulates rejection activity against liver grafts in humans. Copyright © 2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

The funding landscape for HIV in Asia and the Pacific

PubMed Central

Stuart, Robyn M; Lief, Eric; Donald, Braedon; Wilson, David; Wilson, David P

2015-01-01

Introduction Despite recent and robust economic growth across the Asia-Pacific region, the majority of low- and middle-income countries in the region remain dependent on some donor support for HIV programmes. We describe the availability of bilateral and multilateral official development assistance (ODA) for HIV programmes in the region. Methods The donor countries considered in this analysis are Australia, Canada, Denmark, France, Germany, Netherlands, Norway, Sweden, the United Kingdom and the United States. To estimate bilateral and multilateral ODA financing for HIV programmes in the Asia-Pacific region between 2004 and 2013, we obtained funding data from the Organisation for Economic Co-operation and Development Creditor Reporting System database. Where possible, we checked these amounts against the funding data available from government aid agencies. Estimates of multilateral ODA financing for HIV/AIDS were based on the country allocations announcement by the Global Fund to Fight AIDS, Tuberculosis and Malaria (the Global Fund) for the period 2014 to 2016. Results Countries in the Asia-Pacific region receive the largest share of aid for HIV from the Global Fund. Bilateral funding for HIV in the region has been relatively stable over the last decade and is projected to remain below 10% of the worldwide response to the epidemic. Bilateral donors continue to prioritize ODA for HIV to other regions, particularly sub-Saharan Africa; Australia is an exception in prioritizing the Asia-Pacific region, but the United States is the bilateral donor providing the greatest amount of assistance in the region. Funding from the Global Fund has increased consistently since 2005, reaching a total of US$1.2 billion for the Asia-Pacific region from 2014 to 2016. Conclusions Even with Global Fund allocations, countries in the Asia-Pacific region will not have enough resources to meet their epidemiological targets. Prevention funding is particularly vulnerable and requires greater domestic leadership and coordination. Bilateral donors are still crucially important in the response to HIV throughout the Asia-Pacific region. PMID:26578252

The funding landscape for HIV in Asia and the Pacific.

PubMed

Stuart, Robyn M; Lief, Eric; Donald, Braedon; Wilson, David; Wilson, David P

2015-01-01

Despite recent and robust economic growth across the Asia-Pacific region, the majority of low- and middle-income countries in the region remain dependent on some donor support for HIV programmes. We describe the availability of bilateral and multilateral official development assistance (ODA) for HIV programmes in the region. The donor countries considered in this analysis are Australia, Canada, Denmark, France, Germany, Netherlands, Norway, Sweden, the United Kingdom and the United States. To estimate bilateral and multilateral ODA financing for HIV programmes in the Asia-Pacific region between 2004 and 2013, we obtained funding data from the Organisation for Economic Co-operation and Development Creditor Reporting System database. Where possible, we checked these amounts against the funding data available from government aid agencies. Estimates of multilateral ODA financing for HIV/AIDS were based on the country allocations announcement by the Global Fund to Fight AIDS, Tuberculosis and Malaria (the Global Fund) for the period 2014 to 2016. Countries in the Asia-Pacific region receive the largest share of aid for HIV from the Global Fund. Bilateral funding for HIV in the region has been relatively stable over the last decade and is projected to remain below 10% of the worldwide response to the epidemic. Bilateral donors continue to prioritize ODA for HIV to other regions, particularly sub-Saharan Africa; Australia is an exception in prioritizing the Asia-Pacific region, but the United States is the bilateral donor providing the greatest amount of assistance in the region. Funding from the Global Fund has increased consistently since 2005, reaching a total of US$1.2 billion for the Asia-Pacific region from 2014 to 2016. Even with Global Fund allocations, countries in the Asia-Pacific region will not have enough resources to meet their epidemiological targets. Prevention funding is particularly vulnerable and requires greater domestic leadership and coordination. Bilateral donors are still crucially important in the response to HIV throughout the Asia-Pacific region.

Upfront haploidentical transplant for acquired severe aplastic anemia: registry-based comparison with matched related transplant.

PubMed

Xu, Lan-Ping; Jin, Song; Wang, Shun-Qing; Xia, Ling-Hui; Bai, Hai; Gao, Su-Jun; Liu, Qi-Fa; Wang, Jian-Min; Wang, Xin; Jiang, Ming; Zhang, Xi; Wu, De-Pei; Huang, Xiao-Jun

2017-01-21

Haploidentical donor (HID) hematopoietic stem cell transplantation (HSCT) is an alternative treatment method for severe aplastic anemia (SAA) patients lacking suitable identical donors and those who are refractory to immunosuppressive therapy (IST). The current study evaluated the feasibility of upfront haploidentical HSCT in SAA patients. We conducted a multicenter study based on a registry database. One hundred fifty-eight SAA patients who underwent upfront transplantation between June 2012 and September 2015 were enrolled. Eighty-nine patients had haploidentical donors (HIDs), and 69 had matched related donors (MRDs) for HSCT. The median times for myeloid engraftment in the HID and MRD cohorts were 12 (range, 9-20) and 11 (range, 8-19) days, with a cumulative incidence of 97.8 and 97.1% (P = 0.528), respectively. HID recipients had an increased cumulative incidence of grades II-IV acute graft-versus-host disease (aGVHD) (30.3 vs. 1.5%, P < 0.001), grades III-IV aGVHD (10.1 vs. 1.5%, P = 0.026), and chronic GVHD (cGVHD) (30.6 vs. 4.4%, P < 0.001) at 1 year but similar extensive cGVHD (3.4 vs. 0%, P = 0.426). The three-year estimated overall survival (OS) rates were 86.1 and 91.3% (P = 0.358), while the three-year estimated failure-free survival (FFS) rates were 85.0 and 89.8% (P = 0.413) in the HID and MRD cohorts, respectively. In multivariate analysis, survival outcome for the entire population was significantly adversely associated with increased transfusions and poor performance status pre-SCT. We did not observe differences in primary engraftment and survival outcomes by donor type. Haploidentical SCT as upfront therapy was an effective and safe option for SAA patients, with favorable outcomes in experienced centers.

Viscosity-adjusted estimation of pressure head and pump flow with quasi-pulsatile modulation of rotary blood pump for a total artificial heart.

PubMed

Yurimoto, Terumi; Hara, Shintaro; Isoyama, Takashi; Saito, Itsuro; Ono, Toshiya; Abe, Yusuke

2016-09-01

Estimation of pressure and flow has been an important subject for developing implantable artificial hearts. To realize real-time viscosity-adjusted estimation of pressure head and pump flow for a total artificial heart, we propose the table estimation method with quasi-pulsatile modulation of rotary blood pump in which systolic high flow and diastolic low flow phased are generated. The table estimation method utilizes three kinds of tables: viscosity, pressure and flow tables. Viscosity is estimated from the characteristic that differential value in motor speed between systolic and diastolic phases varies depending on viscosity. Potential of this estimation method was investigated using mock circulation system. Glycerin solution diluted with salty water was used to adjust viscosity of fluid. In verification of this method using continuous flow data, fairly good estimation could be possible when differential pulse width modulation (PWM) value of the motor between systolic and diastolic phases was high. In estimation under quasi-pulsatile condition, inertia correction was provided and fairly good estimation was possible when the differential PWM value was high, which was not different from the verification results using continuous flow data. In the experiment of real-time estimation applying moving average method to the estimated viscosity, fair estimation could be possible when the differential PWM value was high, showing that real-time viscosity-adjusted estimation of pressure head and pump flow would be possible with this novel estimation method when the differential PWM value would be set high.

Hepatitis B transmission by cell and tissue allografts: How safe is safe enough?

PubMed Central

Solves, Pilar; Mirabet, Vicente; Alvarez, Manuel

2014-01-01

More than 2 million human tissue transplants (bone, tendon, cartilage, skin, cornea, amniotic membrane, stem cells, heart valve, blood vessel, etc.), are performed worldwide every year. Cells and tissues are shared between countries which have different regulations and laboratory equipment and represent a risk of hepatitis B virus (HBV) transmission that has become a global safety concern. While the risk of transfusion-transmitted HBV infection from blood donations has been estimated, the rate of HBV transmission from donors to recipients of allografts is unknown and varies between different tissues. There are various important ways of reducing the transmission risk, but donor screening and donor testing are still the main factors for preventing HBV transmission. HBV detection is included in the routine screening tests for cell and tissue donors. The standard test for preventing transplant-transmitted hepatitis B is the hepatitis B surface antigen. The implementation of methods involving nucleic acid amplification and the new generation of reactives to detect viral antibodies or antigens with an immunoassay, has increased the sensitivity and the specificity of the screening tests. The objective of our research was to review the literature and critically analyse the different steps for avoiding HBV transmission in cell and tissue donors, focusing on the screening tests performed. PMID:24966613

Predicting Hydride Donor Strength via Quantum Chemical Calculations of Hydride Transfer Activation Free Energy.

PubMed

Alherz, Abdulaziz; Lim, Chern-Hooi; Hynes, James T; Musgrave, Charles B

2018-01-25

We propose a method to approximate the kinetic properties of hydride donor species by relating the nucleophilicity (N) of a hydride to the activation free energy ΔG ⧧ of its corresponding hydride transfer reaction. N is a kinetic parameter related to the hydride transfer rate constant that quantifies a nucleophilic hydridic species' tendency to donate. Our method estimates N using quantum chemical calculations to compute ΔG ⧧ for hydride transfers from hydride donors to CO 2 in solution. A linear correlation for each class of hydrides is then established between experimentally determined N values and the computationally predicted ΔG ⧧ ; this relationship can then be used to predict nucleophilicity for different hydride donors within each class. This approach is employed to determine N for four different classes of hydride donors: two organic (carbon-based and benzimidazole-based) and two inorganic (boron and silicon) hydride classes. We argue that silicon and boron hydrides are driven by the formation of the more stable Si-O or B-O bond. In contrast, the carbon-based hydrides considered herein are driven by the stability acquired upon rearomatization, a feature making these species of particular interest, because they both exhibit catalytic behavior and can be recycled.

Impact of preimplantation genetic screening on donor oocyte-recipient cycles in the United States.

PubMed

Barad, David H; Darmon, Sarah K; Kushnir, Vitaly A; Albertini, David F; Gleicher, Norbert

2017-11-01

Our objective was to estimate the contribution of preimplantation genetic screening to in vitro fertilization pregnancy outcomes in donor oocyte-recipient cycles. This was a retrospective cross-sectional study of US national data from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System between 2005 and 2013. Society for Assisted Reproductive Technology Clinic Outcome Reporting relies on voluntarily annual reports by more than 90% of US in vitro fertilization centers. We evaluated pregnancy and live birth rates in donor oocyte-recipient cycles after the first embryo transfer with day 5/6 embryos. Statistical models, adjusted for patient and donor ages, number of embryos transferred, race, infertility diagnosis, and cycle year were created to compare live birth rates in 392 preimplantation genetic screening and 20,616 control cycles. Overall, pregnancy and live birth rates were significantly lower in preimplantation genetic screening cycles than in control cycles. Adjusted odds of live birth for preimplantation genetic screening cycles were reduced by 35% (odds ratio, 0.65, 95% confidence interval, 0.53-0.80; P < .001). Preimplantation genetic screening, as practiced in donor oocyte-recipient cycles over the past 9 years, has not been associated with improved odds of live birth or reduction in miscarriage rates. Copyright © 2017 Elsevier Inc. All rights reserved.

Assisted reproductive technology with donor sperm: national trends and perinatal outcomes.

PubMed

Gerkowicz, Sabrina A; Crawford, Sara B; Hipp, Heather S; Boulet, Sheree L; Kissin, Dmitry M; Kawwass, Jennifer F

2018-04-01

Information regarding the use of donor sperm in assisted reproductive technology, as well as subsequent treatment and perinatal outcomes, remains limited. Outcome data would aid patient counseling and clinical decision making. The objectives of the study were to report national trends in donor sperm utilization and live birth rates of donor sperm-assisted reproductive technology cycles in the United States and to compare assisted reproductive technology treatment and perinatal outcomes between cycles using donor and nondonor sperm. We hypothesize these outcomes to be comparable between donor and nondonor sperm cycles. This was a retrospective cohort study using data from all US fertility centers reporting to the Centers for Disease Control and Prevention's National Assisted Reproductive Technology Surveillance System, accounting for ∼98% of assisted reproductive technology cycles (definition excludes intrauterine insemination). The number and percentage of assisted reproductive technology cycles using donor sperm and rates of pregnancy, live birth, preterm birth (<37 weeks), and low birthweight (<2500 g) were the primary outcomes measured. Treatments assessed include use of donor vs nondonor sperm. The trends analysis included all banking and fresh assisted reproductive technology cycles using donor and autologous oocytes performed between 1996 and 2014 (n = 1,710,034). The outcomes analysis was restricted to include only fresh autologous cycles performed between 2010 and 2014 (n = 437,569) to focus on cycles with a potential outcome and cycles reflective of current practice, thereby improving the clinical relevance. Cycles canceled prior to retrieval were excluded. Statistical analysis included linear regression to explore polynomial trends and log-binomial regression to estimate relative risk for outcomes among cycles using donor and nondonor sperm. Of all banking and fresh donor and autologous oocyte assisted reproductive technology cycles performed between 1996 and 2014, 74,892 (4.4%) used donor sperm. In 2014, 7351 assisted reproductive technology cycles using donor sperm were performed, as compared with 1763 in 1996 (6.2% vs 3.8% of all cycles). Among all autologous oocyte cycles performed between 2010 and 2014, the live birth rate was lower for donor sperm (27.9%) than nondonor sperm cycles (32.5%); however, after adjustment for maternal age, donor sperm use was associated with an increased likelihood of live birth (adjusted relative risk, 1.06, 95% confidence interval, 1.01-1.10). Per transfer, there was no significant difference in live birth rates for donor vs nondonor sperm (31.9% vs 36.8%; adjusted relative risk, 1.04, 95% confidence interval, 0.998-1.09). Per singleton live birth, there was no significant difference in preterm birth (11.5% vs 11.8%; adjusted relative risk, 0.98, 95% confidence interval, 0.90-1.06); however, low birthweight delivery was slightly lower in donor sperm cycles (8.8% vs 9.4%; adjusted relative risk, 0.91, 95% confidence interval, 0.83-0.99). Donor sperm use in assisted reproductive technology has increased in the United States, accounting for approximately 6% of all assisted reproductive technology cycles in 2014. Assisted reproductive technology treatment and perinatal outcomes were clinically similar in donor and nondonor sperm cycles. Copyright © 2018 Elsevier Inc. All rights reserved.

Complex Contagion of Campaign Donations.

PubMed

Traag, Vincent A

2016-01-01

Money is central in US politics, and most campaign contributions stem from a tiny, wealthy elite. Like other political acts, campaign donations are known to be socially contagious. We study how campaign donations diffuse through a network of more than 50,000 elites and examine how connectivity among previous donors reinforces contagion. We find that the diffusion of donations is driven by independent reinforcement contagion: people are more likely to donate when exposed to donors from different social groups than when they are exposed to equally many donors from the same group. Counter-intuitively, being exposed to one side may increase donations to the other side. Although the effect is weak, simultaneous cross-cutting exposure makes donation somewhat less likely. Finally, the independence of donors in the beginning of a campaign predicts the amount of money that is raised throughout a campaign. We theorize that people infer population-wide estimates from their local observations, with elites assessing the viability of candidates, possibly opposing candidates in response to local support. Our findings suggest that theories of complex contagions need refinement and that political campaigns should target multiple communities.

Complex Contagion of Campaign Donations

PubMed Central

2016-01-01

Money is central in US politics, and most campaign contributions stem from a tiny, wealthy elite. Like other political acts, campaign donations are known to be socially contagious. We study how campaign donations diffuse through a network of more than 50000 elites and examine how connectivity among previous donors reinforces contagion. We find that the diffusion of donations is driven by independent reinforcement contagion: people are more likely to donate when exposed to donors from different social groups than when they are exposed to equally many donors from the same group. Counter-intuitively, being exposed to one side may increase donations to the other side. Although the effect is weak, simultaneous cross-cutting exposure makes donation somewhat less likely. Finally, the independence of donors in the beginning of a campaign predicts the amount of money that is raised throughout a campaign. We theorize that people infer population-wide estimates from their local observations, with elites assessing the viability of candidates, possibly opposing candidates in response to local support. Our findings suggest that theories of complex contagions need refinement and that political campaigns should target multiple communities. PMID:27077742

Quantitative tomographic imaging of intermolecular FRET in small animals

PubMed Central

Venugopal, Vivek; Chen, Jin; Barroso, Margarida; Intes, Xavier

2012-01-01

Forster resonance energy transfer (FRET) is a nonradiative transfer of energy between two fluorescent molecules (a donor and an acceptor) in nanometer range proximity. FRET imaging methods have been applied to proteomic studies and drug discovery applications based on intermolecular FRET efficiency measurements and stoichiometric measurements of FRET interaction as quantitative parameters of interest. Importantly, FRET provides information about biomolecular interactions at a molecular level, well beyond the diffraction limits of standard microscopy techniques. The application of FRET to small animal imaging will allow biomedical researchers to investigate physiological processes occurring at nanometer range in vivo as well as in situ. In this work a new method for the quantitative reconstruction of FRET measurements in small animals, incorporating a full-field tomographic acquisition system with a Monte Carlo based hierarchical reconstruction scheme, is described and validated in murine models. Our main objective is to estimate the relative concentration of two forms of donor species, i.e., a donor molecule involved in FRETing to an acceptor close by and a nonFRETing donor molecule. PMID:23243567

Assessment of Environmental Flows under Human Intervention and Climate Change Conditions in a Mediterranean Watershed

NASA Astrophysics Data System (ADS)

Yilmaz, M. T.; Alp, E.; Aras, M.; Özaltın, A. M.; Sarıcan, Y.; Afsar, M.; Bulut, B.; Ersoy, E. N.; Karasu, İ. G.; Onen, A.

2017-12-01

Allocation of the river flow for ecosystems is very critical for sustainable management of ecosystems containing aquatic habitats in need of more water than other environments. Availability and allocation of water over such locations becomes more stressed as a result of the influence of human interventions (e.g., increased water use for irrigation) and the expected change in climate. This study investigates the current and future (until 2100) low-flow requirements over 10 subcatchments in a Mediterranean Watershed, in Turkey, using Tennant and hydrological low-flow methods. The future river flows are estimated using HBV model forced by climate projections obtained by HADGEM2, MPI-ESM-MR, and CNRM-CM5.1 models coupled with RegCM4.3 under RCP 4.5 and RCP 8.5 emission scenarios. Critical flows (i.e., Q10, Q25, Q50) are calculated using the best fit to commonly used distributions for the river flow data, while the decision between the selection of Q10, Q25, Q50 critical levels are made depending on the level of human interference made over the catchment. Total three low-flow requirement estimations are obtained over each subcatchment using the Tennant (two estimates for the low and high flow seasons for environmentally good conditions) and the hydrological low-flow methods. The highest estimate among these three methods is selected as the low-flow requirement of the subcatchment. The river flows over these 10 subcatchments range between 197hm3 and 1534hm3 while the drainage areas changing between 936 and 4505 km2. The final low-flow estimation (i.e., the highest among the three estimate) for the current conditions range between 94 hm3 and 715 hm3. The low-flow projection values between 2075 and 2099 are on average 39% lower than the 2016 values, while the steepest decline is expected between 2050 and 2074. The low flow and high flow season Tennant estimates dropped 22-25% while the hydrological method low-flow estimates dropped 32% from 2016 to 2075-2099 average, where Tennant estimates are sensitive to the precipitation projections while hydrological flow estimates are sensitive to the degree that the subcatchment flows are regulated/intervened. On the other hand, the combined low-flow estimate, the highest of three methods, dropped around 39%, reflecting combined impact of human intervention and climate change.

A specific immune tolerance toward offspring cells is to exist after the mother lymphocyte infusion.

PubMed

Xing, Haizhou; Liu, Shiqin; Chen, Xue; Fang, Fang; Wu, Xueqiang; Zhu, Ping

2017-04-01

To examine immune tolerance between maternal lymphocytes and offspring tissue after a donor lymphocyte infusion. Mouse models were established by mating female BALB/c mice with male C57BL mice. Splenic lymphocytes from donors of different genetic backgrounds were labeled with carboxyfluorescein succinimidyl ester (CFSE), and 1×10 7 of the labeled cells were intravenously injected into a recipient. At 6h, 24h, 72h and 120h after the infusion, mononuclear cells in recipient spleen, liver, thymus, lymph nodes, and peripheral blood were collected. CFSE+, CFSE-, CD3+, CD8+, CD4+, CD19+, NK1.1+, CD25+, and CD127+ lymphocytes in those samples were analyzed by flow cytometry. The distribution of donor T cells, B cells, NK cells, helper T cells, cytotoxic T cells, and recipient regulatory T cells in the tissues were then analyzed. Maternal lymphocytes were more likely to survive in offspring. At 120h after infusion, the percentages of maternal cells in the offspring were 0.52±0.11% in lymph nodes, 0.97±0.04% in peripheral blood, and 0.97±0.11% in the spleen. Few donor cells, if any, were detected in these tissues at 120h after aunt to child, father to child, and unrelated allogeneic infusions were performed. The subtype proportion of donor lymphocytes changed significantly in the recipient tissues. Recipient Treg cells increased in the mother to child group, but not in the aunt to child, father to child, and unrelated allogeneic groups, suggesting a decreased cellular immune response to allogeneic cells in the mother to child group. At 120h after the infusion, no donor cells were detected in the recipient livers and thymuses of all groups, implying that donor cells were barely able to colonize in the liver and thymus. Specific immune tolerance to maternal lymphocytes exists in offspring. An infusion of maternal donor lymphocytes may produce a relatively persistent effect of adoptive immunotherapy with reduced side-effects. Copyright © 2017 Elsevier GmbH. All rights reserved.

The heterogeneous HLA genetic composition of the Brazilian population and its relevance to the optimization of hematopoietic stem cell donor recruitment.

PubMed

Fabreti-Oliveira, R A; Nascimento, E; Fonseca, C G; Santos, M A

2014-08-01

The aim of this study was to investigate the human leukocyte antigen (HLA) molecular variation across the Brazilian population in order to determine possible regional differences, which would be highly relevant to optimizing donor recruitment strategies in hematopoietic stem cell transplantation (HSCT) and understanding the population genetic background of this heterogeneous country. HLA data of 551 HSCT donors from five Brazilian regions were characterized by high-resolution DNA alleles at the HLA-A, -B, -C, -DRB1 and -DQB1 loci and compared with other populations in Brazil and worldwide populations. Allele and haplotype frequencies were estimated. The analysis was performed to assess Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD) among different loci in each recruitment center. Genetic variation was explored through genetic distance analyzed by using a new algorithm based on linear algebra, taking into account geographic regions of Brazil. The results indicated a heterogeneous genetic composition of the Brazilian population, such that HLA allele and haplotype frequencies exhibit different distributions among Brazilian regions, which has important implications for donor matching. In addition, a pronounced differentiation was observed by the absence of clustering of the regional populations in the reduced-dimension space. These data may be useful for increasing donor recruitment with more genetic representativeness in the Brazilian Volunteer Bone Marrow Donors Registry (REDOME). © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Interpretation of Flow Logs from Nevada Test Site Boreholes to Estimate Hydraulic Conductivity Using Numerical Simulations Constrained by Single-Well Aquifer Tests

USGS Publications Warehouse

Garcia, C. Amanda; Halford, Keith J.; Laczniak, Randell J.

2010-01-01

Hydraulic conductivities of volcanic and carbonate lithologic units at the Nevada Test Site were estimated from flow logs and aquifer-test data. Borehole flow and drawdown were integrated and interpreted using a radial, axisymmetric flow model, AnalyzeHOLE. This integrated approach is used because complex well completions and heterogeneous aquifers and confining units produce vertical flow in the annular space and aquifers adjacent to the wellbore. AnalyzeHOLE simulates vertical flow, in addition to horizontal flow, which accounts for converging flow toward screen ends and diverging flow toward transmissive intervals. Simulated aquifers and confining units uniformly are subdivided by depth into intervals in which the hydraulic conductivity is estimated with the Parameter ESTimation (PEST) software. Between 50 and 150 hydraulic-conductivity parameters were estimated by minimizing weighted differences between simulated and measured flow and drawdown. Transmissivity estimates from single-well or multiple-well aquifer tests were used to constrain estimates of hydraulic conductivity. The distribution of hydraulic conductivity within each lithology had a minimum variance because estimates were constrained with Tikhonov regularization. AnalyzeHOLE simulated hydraulic-conductivity estimates for lithologic units across screened and cased intervals are as much as 100 times less than those estimated using proportional flow-log analyses applied across screened intervals only. Smaller estimates of hydraulic conductivity for individual lithologic units are simulated because sections of the unit behind cased intervals of the wellbore are not assumed to be impermeable, and therefore, can contribute flow to the wellbore. Simulated hydraulic-conductivity estimates vary by more than three orders of magnitude across a lithologic unit, indicating a high degree of heterogeneity in volcanic and carbonate-rock units. The higher water transmitting potential of carbonate-rock units relative to volcanic-rock units is exemplified by the large difference in their estimated maximum hydraulic conductivity; 4,000 and 400 feet per day, respectively. Simulated minimum estimates of hydraulic conductivity are inexact and represent the lower detection limit of the method. Minimum thicknesses of lithologic intervals also were defined for comparing AnalyzeHOLE results to hydraulic properties in regional ground-water flow models.

Genetic analysis of superovulatory response of Holstein cows in Canada.

PubMed

Jaton, C; Koeck, A; Sargolzaei, M; Malchiodi, F; Price, C A; Schenkel, F S; Miglior, F

2016-05-01

Superovulation of dairy cattle is frequently used in Canada. The cost of this protocol is high, and so is the variability of the outcome. Knowing the superovulatory potential of a donor cow could influence the breeder's decision to superovulate it or not. The main objective of this study was to perform a genetic analysis for superovulatory response of Holstein cows in Canada using data recorded by Holstein Canada, and to investigate if these data could be used for genetic evaluation. Data contained the total number of embryos and the number of viable embryos from every successful flushing performed across Canada. After editing, 137,446 records of superovulation performed between 1992 and 2014 were analyzed. A univariate repeatability animal model analysis was performed for both total number of embryos and number of viable embryos. Because both data and residuals did not follow a normal distribution, records were subject to either logarithmic or Anscombe transformation. Using logarithmic transformation, heritability estimates (SE) of 0.15 (0.01) and 0.14 (0.01) were found for total number of embryos and number of viable embryos, respectively. Using Anscombe transformation, heritability estimates (SE) of 0.17 (0.01) and 0.14 (0.01) were found for total number of embryos and number of viable embryos, respectively. The genetic correlation between the 2 traits was estimated at 0.97 using logarithmic transformation and 0.95 using Anscombe transformation. Breeding values were estimated for 54,463 cows, and 3,513 sires. Only estimated breeding values of sires having a reliability higher than 40% were considered for estimated breeding values correlations with other routinely evaluated traits. The results showed that selection for a higher response to superovulation would lead to a slight decrease in milk production, but an improvement for functional traits, including all reproduction traits. In all cases, the estimated correlations are either low or modest. We conclude that genetic selection for increased superovulatory response in donors is possible; daughters of sires with high estimated breeding values for superovulatory response will tend to yield more embryos, whereas the additive effect of service sire seems not to contribute to the variability of the 2 superovulation traits and was not significantly correlated with the additive effect of the donor. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Low-flow characteristics of streams in Virginia

USGS Publications Warehouse

Hayes, Donald C.

1991-01-01

Streamflow data were collected and low-flow characteristics computed for 715 gaged sites in Virginia Annual minimum average 7-consecutive-day flows range from 0 to 2,195 cubic feet per second for a 2-year recurrence interval and from 0 to 1,423 cubic feet per second for a 10-year recurrence interval. Drainage areas range from 0.17 to 7,320 square miles. Existing and discontinued gaged sites are separated into three types: long-term continuous-record sites, short-term continuous-record sites, and partial-record sites. Low-flow characteristics for long-term continuous-record sites are determined from frequency curves of annual minimum average 7-consecutive-day flows . Low-flow characteristics for short-term continuous-record sites are estimated by relating daily mean base-flow discharge values at a short-term site to concurrent daily mean discharge values at nearby long-term continuous-record sites having similar basin characteristics . Low-flow characteristics for partial-record sites are estimated by relating base-flow measurements to daily mean discharge values at long-term continuous-record sites. Information from the continuous-record sites and partial-record sites in Virginia are used to develop two techniques for estimating low-flow characteristics at ungaged sites. A flow-routing method is developed to estimate low-flow values at ungaged sites on gaged streams. Regional regression equations are developed for estimating low-flow values at ungaged sites on ungaged streams. The flow-routing method consists of transferring low-flow characteristics from a gaged site, either upstream or downstream, to a desired ungaged site. A simple drainage-area proration is used to transfer values when there are no major tributaries between the gaged and ungaged sites. Standard errors of estimate for108 test sites are 19 percent of the mean for estimates of low-flow characteristics having a 2-year recurrence interval and 52 percent of the mean for estimates of low-flow characteristics having a 10-year recurrence interval . A more complex transfer method must be used when major tributaries enter the stream between the gaged and ungaged sites. Twenty-four stream networks are analyzed, and predictions are made for 84 sites. Standard errors of estimate are 15 percent of the mean for estimates of low-flow characteristics having a 2-year recurrence interval and 22 percent of the mean for estimates of low-flow characteristics having a 10-year recurrence interval. Regional regression equations were developed for estimating low-flow values at ungaged sites on ungaged streams. The State was divided into eight regions on the basis of physiography and geographic grouping of the residuals computed in regression analyses . Basin characteristics that were significant in the regression analysis were drainage area, rock type, and strip-mined area. Standard errors of prediction range from 60 to139 percent for estimates of low-flow characteristics having a 2-year recurrence interval and 90 percent to 172 percent for estimates of low-flow characteristics having a 10-year recurrence interval.

Scalable alignment of CdS nanowires based on efficient roll-on transfer technique.

PubMed

Yan, Shancheng; Shi, Yi; Xiao, Zhongdang; Wang, Junzhuan; Hu, Dong; Xul, Xin; Lu, Tao; Liu, Aili; Gao, Fan

2013-06-01

A roll-on transfer strategy is developed to enable large-scale and uniform assembly of CdS nanowires on various rigid and flexible substrate materials. In this method, the CdS nanowires were synthesized by the hydrothermal method. The dispersed CdS NWs could be firstly aligned and selectively deposited at the micro/nanochannels between aligned nanofibers on the surface of the donor roller as a result of evaporation-induced flow and capillary action, and then the directional and aligned transfer of the CdS NWs from the donor roller to a receiver substrate via roll-on transfer technique. Finally, a device structures consisting of the nanowire channel and two metal electrodes was fabricated. The electrical property of this device was observed.

3-D Vector Flow Estimation With Row-Column-Addressed Arrays.

PubMed

Holbek, Simon; Christiansen, Thomas Lehrmann; Stuart, Matthias Bo; Beers, Christopher; Thomsen, Erik Vilain; Jensen, Jorgen Arendt

2016-11-01

Simulation and experimental results from 3-D vector flow estimations for a 62 + 62 2-D row-column (RC) array with integrated apodization are presented. A method for implementing a 3-D transverse oscillation (TO) velocity estimator on a 3-MHz RC array is developed and validated. First, a parametric simulation study is conducted, where flow direction, ensemble length, number of pulse cycles, steering angles, transmit/receive apodization, and TO apodization profiles and spacing are varied, to find the optimal parameter configuration. The performance of the estimator is evaluated with respect to relative mean bias ~B and mean standard deviation ~σ . Second, the optimal parameter configuration is implemented on the prototype RC probe connected to the experimental ultrasound scanner SARUS. Results from measurements conducted in a flow-rig system containing a constant laminar flow and a straight-vessel phantom with a pulsating flow are presented. Both an M-mode and a steered transmit sequence are applied. The 3-D vector flow is estimated in the flow rig for four representative flow directions. In the setup with 90° beam-to-flow angle, the relative mean bias across the entire velocity profile is (-4.7, -0.9, 0.4)% with a relative standard deviation of (8.7, 5.1, 0.8)% for ( v x , v y , v z ). The estimated peak velocity is 48.5 ± 3 cm/s giving a -3% bias. The out-of-plane velocity component perpendicular to the cross section is used to estimate volumetric flow rates in the flow rig at a 90° beam-to-flow angle. The estimated mean flow rate in this setup is 91.2 ± 3.1 L/h corresponding to a bias of -11.1%. In a pulsating flow setup, flow rate measured during five cycles is 2.3 ± 0.1 mL/stroke giving a negative 9.7% bias. It is concluded that accurate 3-D vector flow estimation can be obtained using a 2-D RC-addressed array.

Lost potential of kidney and liver donors amongst deceased intracerebral hemorrhage patients.

PubMed

Sairanen, T; Koivisto, A; Koivusalo, A-M; Rantanen, K; Mustanoja, S; Meretoja, A; Putaala, J; Strbian, D; Kaste, M; Isoniemi, H; Tatlisumak, T

2014-01-01

Intracerebral hemorrhage (ICH) has high acute mortality. The number of potential kidney and liver donors amongst deceased ICH patients was estimated to improve our institutional guidelines on acute care of neurocritical patients to increase organ donation. A chart review was carried out by a multi-professional team for consecutive ICH patients admitted to the emergency department at Helsinki University Central Hospital and dying within 14 days between 2005 and 2010. In all, 955 patients had follow-up data, of whom 254 (27%) died within 14 days and eight ended up as organ donors. An additional 51 potentially suitable donors not different from actual donors were identified: nine suitable for kidney donation, 11 for liver and 31 for both. In 49/51 (96%) cases prognosis seemed non-existent and do-not-resuscitate orders were issued early, which led to refrainment from intensive care in 76.5%. These potential donors differed from those ICH patients surviving a whole year (n = 529) by male preponderance, more severe symptoms (median National Institutes of Health Stroke Scale 25 vs. 6 and Glasgow Coma Scale 7 vs. 15), larger hematoma volumes of 24.8 cm(3) (vs. 6.7), and frequent finding of midline shift and intraventricular rupture of the hemorrhage in admission brain CT. Based on the results, our guidelines were revised towards more active treatment including mechanical ventilation for neurocritical patients at the emergency department for at least 48 h, resulting in an increase in organ donations in 2012. A considerable number of ICH patients are potential organ donors if the evaluation takes place on arrival and organ donation is considered as part of usual end-of-life care. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

Utility of applying quality assessment tools for kidneys with KDPI ≥80

PubMed Central

Doshi, Mona D.; Reese, Peter P.; Hall, Isaac E.; Schröppel, Bernd; Ficek, Joseph; Formica, Richard N.; Weng, Francis L.; Hazs, Rick D.; Philbrook, Heather Thiessen; Parikh, Chirag

2016-01-01

Background Kidneys with “high” kidney donor profile index (KDPI) are often biopsied and pumped, yet frequently discarded. Methods In this multicenter study, we describe the characteristics and outcomes of kidneys with KDPI ≥80 that were procured from 338 deceased donors. We excluded donors with anatomical kidney abnormalities. Results Donors were categorized by the number of kidneys discarded: 1) none (n=154, 46%), 2) 1 discarded and 1 transplanted (n=48, 14%), 3) both discarded (n=136, 40%). Donors in group 3 were older, more often white, and had higher terminal creatinine and KDPI than group 1 (all p<0.05). Biopsy was performed in 92% of all kidneys, and 47% were pumped. Discard was associated with biopsy findings and 1st hour renal resistance. Kidney injury biomarker levels (NGAL, IL-18, and KIM-1 measured from donor urine at procurement and from perfusate soon after pump perfusion) were not different between groups. There was no significant difference in 1-year estimated glomerular filtration rate (eGFR) or graft failure between groups 1 and 2 (41.5±18 vs. 41.4±22 mL/min/1.73m2; p=0.97 and 9% vs. 10%; p=0.76). Conclusions Kidneys with KDPI ≥80 comprise the most resource consuming fraction of our donor kidney pool and have the highest rates of discard. Our data suggest that some discarded kidneys with KDPI ≥80 are viable; however, current tools and urine- and perfusate-biomarkers to identify these viable kidneys are not satisfactory. We need better methods to assess viability of kidneys with high KDPI. PMID:27490414

Screening blood donors for diabetes: analysis of use, accuracy, and cost.

PubMed

Lenhard, M James; Maser, Raelene E; Kolm, Paul; Healy, Michael J; Seshadri, Prakash

2013-11-01

The objective was to determine if a free, voluntary diabetes screening program as a part of the blood donation process might be cost-effective. During the first 6 months of the program, 26,415 donors were screened using a single random plasma glucose (RPG) level. All donors were asked to eat before donation. Low-, moderate-, and high-risk groups were formed based on RPG levels (<140, 140-200, and >200 mg/dL). Contact with a telephone questionnaire was made with 139 of 178 (78%) of the persons in the high-risk group with 33 new cases of diabetes diagnosed by the donor's physician and 26 donors indicating that they were not diagnosed with diabetes. Sex- and age-matched donors in the low- and moderate-risk groups were contacted and administered the same questionnaire. The three risk groups were similar, except for body mass index (28.1 ± 5.4 kg/m2 vs. 29.9 ± 5.5 kg/m2 vs. 32.7 ± 5.6 kg/m2 , p < 0.001). The discriminative effectiveness of screening was evaluated by the area under the receiver operating characteristics (AROC) curve. The AROC curve was 0.950 (95% confidence interval, 0.920-0.979) for the identification of diabetes. Using a RPG cutoff of 200 mg/dL, sensitivity was 100%, specificity was 82%, and positive predictive value was 56%. Cost analyses showed that the mean cost to screen, per donor, was less than $1. Cost per case identified was estimated to be less than $500 for a RPG cutoff of 200 mg/dL. Screening during the blood donation process appears to be accurate, convenient, and inexpensive. © 2013 American Association of Blood Banks.

Outcomes of various transplant procedures (single, sparing, inverted) in living-donor lobar lung transplantation.

PubMed

Date, Hiroshi; Aoyama, Akihiro; Hijiya, Kyoko; Motoyama, Hideki; Handa, Tomohiro; Kinoshita, Hideyuki; Baba, Shiro; Mizota, Toshiyuki; Minakata, Kenji; Chen-Yoshikawa, Toyofumi F

2017-02-01

In standard living-donor lobar lung transplantation (LDLLT), the right and left lower lobes from 2 healthy donors are implanted. Because of the difficulty encountered in finding 2 donors with ideal size matching, various transplant procedures have been developed in our institution. The purpose of this retrospective study was to compare outcomes of nonstandard LDLLT with standard LDLLT. Between June 2008 and January 2016, we performed 65 LDLLTs for critically ill patients. Functional size matching was performed by estimating graft forced vital capacity based on the donor's measured forced vital capacity and the number of pulmonary segments implanted. For anatomical size matching, 3-dimensional computed tomography volumetry was performed. In cases of oversize mismatch, single-lobe transplant or downsizing transplant was performed. In cases of undersize mismatch, native upper lobe sparing transplant or right-left inverted transplant was performed. In right-left inverted transplants, the donor's right lower lobe was inverted and implanted into the recipient's left chest cavity. Twenty-nine patients (44.6%) received nonstandard LDLLT, including 12 single-lobe transplants, 7 native upper lobe sparing transplants, 6 right-left inverted transplants, 2 sparing + inverted transplants, and 2 others. Thirty-six patients (57.4%) received standard LDLLT. Three- and five-year survival rates were similar between the 2 groups (89.1% and 76.6% after nonstandard LDLLT vs 78.0% and 71.1% after standard LDLLT, P = .712). Various transplant procedures such as single, sparing and inverted transplants are valuable options when 2 donors with ideal size matching are not available for LDLLT. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors.

PubMed

Lentine, Krista L; Kasiske, Bertram L; Levey, Andrew S; Adams, Patricia L; Alberú, Josefina; Bakr, Mohamed A; Gallon, Lorenzo; Garvey, Catherine A; Guleria, Sandeep; Li, Philip Kam-Tao; Segev, Dorry L; Taler, Sandra J; Tanabe, Kazunari; Wright, Linda; Zeier, Martin G; Cheung, Michael; Garg, Amit X

2017-08-01

The 2017 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors is intended to assist medical professionals who evaluate living kidney donor candidates and provide care before, during and after donation. The guideline development process followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach and guideline recommendations are based on systematic reviews of relevant studies that included critical appraisal of the quality of the evidence and the strength of recommendations. However, many recommendations, for which there was no evidence or no systematic search for evidence was undertaken by the Evidence Review Team, were issued as ungraded expert opinion recommendations. The guideline work group concluded that a comprehensive approach to risk assessment should replace decisions based on assessments of single risk factors in isolation. Original data analyses were undertaken to produce a "proof-in-concept" risk-prediction model for kidney failure to support a framework for quantitative risk assessment in the donor candidate evaluation and defensible shared decision making. This framework is grounded in the simultaneous consideration of each candidate's profile of demographic and health characteristics. The processes and framework for the donor candidate evaluation are presented, along with recommendations for optimal care before, during, and after donation. Limitations of the evidence are discussed, especially regarding the lack of definitive prospective studies and clinical outcome trials. Suggestions for future research, including the need for continued refinement of long-term risk prediction and novel approaches to estimating donation-attributable risks, are also provided.In citing this document, the following format should be used: Kidney Disease: Improving Global Outcomes (KDIGO) Living Kidney Donor Work Group. KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors. Transplantation. 2017;101(Suppl 8S):S1-S109.

The distribution of HLA haplotypes in the ethnic groups that make up the Brazilian Bone Marrow Volunteer Donor Registry (REDOME).

PubMed

Halagan, Michael; Oliveira, Danielli Cristina; Maiers, Martin; Fabreti-Oliveira, Raquel A; Moraes, Maria Elisa Hue; Visentainer, Jeane Eliete Laguila; Pereira, Noemi Farah; Romero, Matilde; Cardoso, Juliana Fernandes; Porto, Luís Cristóvão

2018-04-26

The Registries of Bone Marrow Donors around the world include more than 30 million volunteer donors from 57 different countries, and were responsible for over 17,000 hematopoietic stem cell transplants in 2016. The Brazilian Bone Marrow Volunteer Donor Registry (REDOME) was established in 1993 and is the third largest registry in the world with more than 4.3 million donors. We characterized HLA allele and haplotypes frequencies from REDOME comparing them with the donor self-reported race group classification. Five-locus haplotype frequencies (A~C~B~DRB1~DQB1) were estimated for each of the six race groups, resolving phase and allelic ambiguity using the expectation-maximization (EM) algorithm. The top 100 haplotypes in the race groups were separated into eight clusters of haplotypes, based on haplotype similarity, using CLUTO. We present HLA allele and haplotype frequency data from six race groups from 2,938,259 individuals from REDOME. The most frequent haplotype was the same for all groups: A*01:01g~C*07:01g~B*08:01g~DRB1*03:01g~DQB1*02:01g. Some frequent haplotypes such as A*02:01g~C*16:01g~B*44:03~DRB1*07:01g~DQB1*02:01g was not found in people with Preta (Sub-Saharan African descent). A cluster including Branca (European) and Parda or non-informed (admixed) could be distinguished from both Preta (SubSaharan) and Indígena (Amerindian) groups, and from the Amarela (Asian) ones, which clustered with their original population. These results have implications on cross-population matching and can help in donor searches and population-based recruitment strategies.

Global status of visceral leishmanial infection among blood donors: A systematic review and meta-analysis.

PubMed

Asfaram, Shabnam; Fakhar, Mahdi; Soosaraei, Masoud; Hosseini Teshnizi, Saeed; Mardani, Ahmad; Banimostafavi, Elham Sadat; Ziaei Hezarjaribi, Hajar

2017-10-01

Transmission of Leishmania through transfusion has been reported from various Visceral leishmaniasis (VL) endemic areas of the world. The true burden of Leishmania infection in blood donors remains generally unknown. Thus, the present systematic review attempted to determine the global prevalence of Leishmania infection among blood donors. Data were extracted through five English and five Persian databases during the period from 1997 to 2016. Overall, 16 articles fulfilled the inclusion criteria and were used for data extraction in this systematic review. In total, 13,743 blood donors from different regions of world were examined. The prevalence rate of Leishmania infection according to seropositivity obtained 7% (95%CI: 5%, 8%). The lowest and the highest prevalence were related to Bangladesh 0.25% (95%CI: 0.0%, 1.0%) and Brazil, 16% (95%CI: 12%, 19%). Seroprevalence rate of leishmaniasis among females was more (4.60%) than males. Of 15 studies included in the meta-analysis, the pooled prevalence rate of molecular tests was obtained 2% (95%CI: 1%, 3%) in which Iran and Spain had the lowest and the highest prevalence, 0.05% and 7%, respectively. Our analysis showed that L. infantum was more common than L. donovani as etiological agent of VL among all donors. Our data confirms the presence of asymptomatic carriers of VL in endemic areas and supplies as an attentive to the likelihood of these carriers acting as blood donors. Moreover, we conclude that molecular tests for screening in asymptomatic blood donor provide an accurate estimate of the rate of infection over serological tests. Copyright © 2017 Elsevier Ltd. All rights reserved.

Compensatory Hypertrophy After Living Donor Nephrectomy.

PubMed

Chen, K W; Wu, M W F; Chen, Z; Tai, B C; Goh, Y S B; Lata, R; Vathsala, A; Tiong, H Y

2016-04-01

Previous studies have shown that kidney volume enhances the estimation of glomerular filtration rate (eGFR) in kidney donors. This study aimed to describe the phenomenon of compensatory hypertrophy after donor nephrectomy as measured on computerized tomographic (CT) scans. An institutional Domain Specific Review Board (DSRB)-approved study involved approaching kidney donors to have a follow up CT scan from 6 months to 1 year after surgery; 29 patients participated; 55% were female. Clinical chart review was performed, and the patient's remaining kidney volume was measured before and after surgery based on CT scans. eGFR was determined with the use of the Modification of Diet in Renal Disease equation. Mean parenchymal volume of the remaining kidney for this population (mean age, 44.3 ± 8.5 y) was 204.7 ± 82.5 cc before surgery and 250.5 ± 113.3 cc after donor nephrectomy. Compensatory hypertrophy occurred in 79.3% of patients (n = 23). Mean increase in remaining kidney volume was 22.4 ± 23.2% after donor nephrectomy in healthy individuals. Over a median follow-up of 52.9 ± 19.8 months, mean eGFR was 68.9 ± 12.4 mL/min/1.73 m(2), with 24.1% of patients (n = 7) in chronic kidney disease grade 3. Absolute and relative change in kidney volume was not associated with sex, race, surgical approach, or background of hypertension (P = NS). There was a trend of decreased hypertrophy with increasing age (P = .5; Spearman correlation, -0.12). In healthy kidney donors, compensatory hypertrophy of the remaining kidney occurs in 79.3% of the patients, with an average increment of about 22.4%. Older patients may have a blunted compensatory hypertrophy response after surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

Heart transplant outcomes in recipients of Centers for Disease Control (CDC) high risk donors.

PubMed

Tsiouris, Athanasios; Wilson, Lynn; Sekar, Rajesh B; Mangi, Abeel A; Yun, James J

2016-12-01

A lack of donor hearts remains a major limitation of heart transplantation. Hearts from Centers for Disease Control (CDC) high-risk donors can be utilized with specific recipient consent. However, outcomes of heart transplantation with CDC high-risk donors are not well known. We sought to define outcomes, including posttransplant hepatitis and human immunodeficiency virus (HIV) status, in recipients of CDC high-risk donor hearts at our institution. All heart transplant recipients from August 2010 to December 2014 (n = 74) were reviewed. Comparison of 1) CDC high-risk donor (HRD) versus 2) standard-risk donor (SRD) groups were performed using chi-squared tests for nominal data and Wilcoxon two-sample tests for continuous variables. Survival was estimated with Kaplan-Meier curves. Of 74 heart transplant recipients reviewed, 66 (89%) received a SRD heart and eight (11%) received a CDC HRD heart. We found no significant differences in recipient age, sex, waiting list 1A status, pretransplant left ventricular assist device (LVAD) support, cytomegalovirus (CMV) status, and graft ischemia times (p = NS) between the HRD and SRD groups. All of the eight HRD were seronegative at the time of transplant. Postoperatively, there was no significant difference in rejection rates at six and 12 months posttransplant. Importantly, no HRD recipients acquired hepatitis or HIV. Survival in HRD versus SRD recipients was not significantly different by Kaplan-Meier analysis (log rank p = 0.644) at five years posttransplant. Heart transplants that were seronegative at the time of transplant had similar posttransplant graft function, rejection rates, and five-year posttransplant survival versus recipients of SRD hearts. At our institution, no cases of hepatitis or HIV occurred in HRD recipients in early follow-up. © 2016 Wiley Periodicals, Inc.

2222 kidney transplantations at the University Hospital Basel: a story of success and new challenges.

PubMed

Wehmeier, Caroline; Georgalis, Argyrios; Hirt-Minkowski, Patricia; Amico, Patrizia; Hoenger, Gideon; Voegele, Thomas; Brun, Nicole; Bock, Andreas; Wolff, Thomas; Guerke, Lorenz; Bachmann, Alexander; Hopfer, Helmut; Dickenmann, Michael; Steiger, Jürg; Schaub, Stefan

2016-01-01

The aim was to investigate changes in kidney allograft donor/recipient characteristics and outcomes at our centre. We retrospectively reviewed all 2222 kidney transplantations performed between 1967 and 2015. The population was divided into four eras on the basis of time intervals corresponding to major changes in immunosuppression and pretransplant risk stratification: (i.) 1967-1980 (n = 231), (ii.) 1981-1997 (n = 883), (iii.) 1998-2004 (n = 437), (iv.) 2005-2015 (n = 671). In deceased donor transplants, we observed a continuous increase of the median recipient (45, 51, 56 and 58 years; p <0.0001) and donor (26, 36, 49 and 54 years; p <0.0001) age. Notably, the frequency of expanded criteria donors increased dramatically (1%, 10%, 28%, 40%, p <0.0001). Graft survival at 1 year (63%, 82%, 89%, 95%), 5 years (46%, 66%, 72%, 78%) and 10 years (27%, 46%, 48%, 61%) significantly improved (p <0.0001). Patient survival also significantly improved and remained stable at a high level within the last three eras (1 year: 97%; 5 years: 87%; 10 years: 71%). Similar trends along with slightly better outcomes were noticed in living donor transplantations. In the most recent era, graft losses in elderly patients were in 81% of cases related to the patient's death, whereas in young patients 83% of graft losses were caused by transplant failure (mainly rejection). Allograft function at the time of patients' deaths would have allowed for calculated 10 additional years with an estimated glomerular filtration rate >15 ml/min. Despite increasing donor and recipient age, outcomes improved, illustrating ongoing progress in kidney transplantation. A major new challenge is to match the functional capacity of the donor organ with the anticipated lifespan of the recipient.

Different techniques for harvesting grafts for living donor liver transplantation: A systematic review and meta-analysis

PubMed Central

Li, Hui; Zhang, Jun-Bin; Chen, Xiao-Long; Fan, Lei; Wang, Li; Li, Shi-Hui; Zheng, Qiao-Lan; Wang, Xiao-Ming; Yang, Yang; Chen, Gui-Hua; Wang, Gen-Shu

2017-01-01

AIM To perform a systematic review and meta-analysis on minimally vs conventional invasive techniques for harvesting grafts for living donor liver transplantation. METHODS PubMed, Web of Science, EMBASE, and the Cochrane Library were searched comprehensively for studies comparing MILDH with conventional living donor hepatectomy (CLDH). Intraoperative and postoperative outcomes (operative time, estimated blood loss, postoperative liver function, length of hospital stay, analgesia use, complications, and survival rate) were analyzed in donors and recipients. Articles were included if they: (1) compared the outcomes of MILDH and CLDH; and (2) reported at least some of the above outcomes. RESULTS Of 937 articles identified, 13, containing 1592 patients, met our inclusion criteria and were included in the meta-analysis. For donors, operative time [weighted mean difference (WMD) = 20.68, 95%CI: -6.25-47.60, P = 0.13] and blood loss (WMD = -32.61, 95%CI: -80.44-5.21, P = 0.18) were comparable in the two groups. In contrast, analgesia use (WMD = -7.79, 95%CI: -14.06-1.87, P = 0.01), postoperative complications [odds ratio (OR) = 0.62, 95%CI: 0.44-0.89, P = 0.009], and length of hospital stay (WMD): -1.25, 95%CI: -2.35-0.14, P = 0.03) significantly favored MILDH. No differences were observed in recipient outcomes, including postoperative complications (OR = 0.93, 95%CI: 0.66-1.31, P = 0.68) and survival rate (HR = 0.96, 95%CI: 0.27-3.47, P = 0.95). Funnel plot and statistical methods showed a low probability of publication bias. CONCLUSION MILDH is safe, effective, and feasible for living donor liver resection with fewer donor postoperative complications, reduced length of hospital stay and analgesia requirement than CLDH. PMID:28611526

Prevalence of hepatitis B infection among young and unsuspecting Hmong blood donors in the Central California Valley.

PubMed

Sheikh, Muhammad Y; Atla, Pradeep R; Raoufi, Rahim; Sadiq, Humaira; Sadler, Patrick C

2012-02-01

Chronic hepatitis B virus (HBV) infection may result in cirrhosis and/or hepatocellular carcinoma and is one of the leading causes of mortality in Asian Americans including Hmong Americans. The Central California Valley is home to a huge Hmong population. To date, the true prevalence of HBV among Hmong is largely unknown. The aim of this study was to contribute to the limited data on HBV prevalence and its trends in Hmong population in the Central California Valley. Between fiscal years 2006 and 2010, a total of 219, 450 voluntary donors were identified at Central California Blood Center in Fresno. Of these, 821 (399 males and 422 females) were Hmong donors. A cross-sectional review of the HBV (hepatitis B surface antigen) positivity among all donors was carried out. Prevalence estimates with 95% confidence intervals (CI) were calculated. Ninety-two percent of Hmong donors were between age groups 16 and 35 years, and only 8% were ≥36 years. The overall prevalence in Hmong was noted at 3.41% (95%CI 2.3-4.9) compared to 0.06% (95%CI 0.05-0.07) in donors of all ethnicities. The calculated prevalence could be an underestimate of the true HBV prevalence in Hmong as the study enrolled only healthy blood donors with predominant younger age (≤35 years) population. These results underscore the persistent burden of HBV infection and potentially increased risk of premature death even in the second generation Hmong community of the Central California Valley. This study reemphasizes the unequivocal need to develop robust preventive and treatment strategies for HBV in Hmong community.

Quality assessment program for EuroFlow protocols: summary results of four-year (2010-2013) quality assurance rounds.

PubMed

Kalina, Tomas; Flores-Montero, Juan; Lecrevisse, Quentin; Pedreira, Carlos E; van der Velden, Vincent H J; Novakova, Michaela; Mejstrikova, Ester; Hrusak, Ondrej; Böttcher, Sebastian; Karsch, Dennis; Sędek, Łukasz; Trinquand, Amelie; Boeckx, Nancy; Caetano, Joana; Asnafi, Vahid; Lucio, Paulo; Lima, Margarida; Helena Santos, Ana; Bonaccorso, Paola; van der Sluijs-Gelling, Alita J; Langerak, Anton W; Martin-Ayuso, Marta; Szczepański, Tomasz; van Dongen, Jacques J M; Orfao, Alberto

2015-02-01

Flow cytometric immunophenotyping has become essential for accurate diagnosis, classification, and disease monitoring in hemato-oncology. The EuroFlow Consortium has established a fully standardized "all-in-one" pipeline consisting of standardized instrument settings, reagent panels, and sample preparation protocols and software for data analysis and disease classification. For its reproducible implementation, parallel development of a quality assurance (QA) program was required. Here, we report on the results of four consecutive annual rounds of the novel external QA EuroFlow program. The novel QA scheme aimed at monitoring the whole flow cytometric analysis process (cytometer setting, sample preparation, acquisition and analysis) by reading the median fluorescence intensities (MedFI) of defined lymphocytes' subsets. Each QA participant applied the predefined reagents' panel on blood cells of local healthy donors. A uniform gating strategy was applied to define lymphocyte subsets and to read MedFI values per marker. The MedFI values were compared with reference data and deviations from reference values were quantified using performance score metrics. In four annual QA rounds, we analyzed 123 blood samples from local healthy donors on 14 different instruments in 11 laboratories from nine European countries. The immunophenotype of defined cellular subsets appeared sufficiently standardized to permit unified (software) data analysis. The coefficient of variation of MedFI for 7 of 11 markers performed repeatedly below 30%, average MedFI in each QA round ranged from 86 to 125% from overall median. Calculation of performance scores was instrumental to pinpoint standardization failures and their causes. Overall, the new EuroFlow QA system for the first time allowed to quantify the technical variation that is introduced in the measurement of fluorescence intensities in a multicentric setting over an extended period of time. EuroFlow QA is a proficiency test specific for laboratories that use standardized EuroFlow protocols. It may be used to complement, but not replace, established proficiency tests. © 2014 International Society for Advancement of Cytometry. © 2014 International Society for Advancement of Cytometry.

Estimation of the REV Size and Equivalent Permeability Coefficient of Fractured Rock Masses with an Emphasis on Comparing the Radial and Unidirectional Flow Configurations

NASA Astrophysics Data System (ADS)

Wang, Zhechao; Li, Wei; Bi, Liping; Qiao, Liping; Liu, Richeng; Liu, Jie

2018-05-01

A method to estimate the representative elementary volume (REV) size for the permeability and equivalent permeability coefficient of rock mass with a radial flow configuration was developed. The estimations of the REV size and equivalent permeability for the rock mass around an underground oil storage facility using a radial flow configuration were compared with those using a unidirectional flow configuration. The REV sizes estimated using the unidirectional flow configuration are much higher than those estimated using the radial flow configuration. The equivalent permeability coefficient estimated using the radial flow configuration is unique, while those estimated using the unidirectional flow configuration depend on the boundary conditions and flow directions. The influences of the fracture trace length, spacing and gap on the REV size and equivalent permeability coefficient were investigated. The REV size for the permeability of fractured rock mass increases with increasing the mean trace length and fracture spacing. The influence of the fracture gap length on the REV size is insignificant. The equivalent permeability coefficient decreases with the fracture spacing, while the influences of the fracture trace length and gap length are not determinate. The applicability of the proposed method to the prediction of groundwater inflow into rock caverns was verified using the measured groundwater inflow into the facility. The permeability coefficient estimated using the radial flow configuration is more similar to the representative equivalent permeability coefficient than those estimated with different boundary conditions using the unidirectional flow configuration.

The Rise of Computing Research in East Africa: The Relationship between Funding, Capacity and Research Community in a Nascent Field

ERIC Educational Resources Information Center

Harsh, Matthew; Bal, Ravtosh; Wetmore, Jameson; Zachary, G. Pascal; Holden, Kerry

2018-01-01

The emergence of vibrant research communities of computer scientists in Kenya and Uganda has occurred in the context of neoliberal privatization, commercialization, and transnational capital flows from donors and corporations. We explore how this funding environment configures research culture and research practices, which are conceptualized as…

Efficacy, outcomes, and cost-effectiveness of desensitization using IVIG and rituximab.

PubMed

Vo, Ashley A; Petrozzino, Jeffrey; Yeung, Kai; Sinha, Aditi; Kahwaji, Joseph; Peng, Alice; Villicana, Rafael; Mackowiak, John; Jordan, Stanley C

2013-03-27

Transplantation rates are very low for the broadly sensitized patient (panel reactive antibody [PRA]>80%; HS). Here, we examine the efficacy, outcomes, and cost-effectiveness of desensitization using high-dose intravenous immunoglobulin (IVIG) and rituximab to improve transplantation rates in HS patients. From July 2006 to December 2011, 207 HS (56 living donors/151 deceased donors) patients (donor-specific antibody positive, PRA>80%) were desensitized using IVIG and rituximab. After desensitization, responsive patients proceeded to transplantation with an acceptable crossmatch. Cost and outcomes of desensitization were compared with dialysis. Of the 207 treated patients, 146 (71%) were transplanted. At 48 months, patient and graft survival by Kaplan-Meier were 95% and 87.5%, respectively. The total 3-year cost for patients treated in the desensitization arm was $219,914 per patient compared with $238,667 per patient treated in the dialysis arm. Thus, each patient treated with desensitization is estimated to save the U.S. healthcare system $18,753 in 2011 USD. Overall, estimated patient survival at the end of 3 years was 96.6% for patients in the desensitization arm of the model (based on Cedars-Sinai survival rate) compared with 79.0% for an age, end-stage renal disease etiology, and PRA matched group of patients remaining on dialysis during the study period. We conclude that desensitization with IVIG+rituximab is clinically and cost-effective, with both financial savings and an estimated 17.6% greater probability of 3-year survival associated with desensitization versus dialysis alone. However, the benefits of desensitization and transplantation are limited by organ availability and allocation policies.

HLA Amino Acid Polymorphisms and Kidney Allograft Survival

PubMed Central

Kamoun, Malek; McCullough, Keith P.; Maiers, Martin; Fernandez Vina, Marcelo A.; Li, Hongzhe; Teal, Valerie; Leichtman, Alan B.; Merion, Robert M.

2017-01-01

Background The association of HLA mismatching with kidney allograft survival has been well established. We examined whether amino acid (AA) mismatches (MMs) at the antigen recognition site of HLA molecules represent independent and incremental risk factors for kidney graft failure (GF) beyond those MMs assessed at the antigenic (2-digit) specificity. Methods Data on 240 024 kidney transplants performed between 1987 and 2009 were obtained from the Scientific Registry of Transplant Recipients. We imputed HLA-A, -B, and -DRB1 alleles and corresponding AA polymorphisms from antigenic specificity through the application of statistical and population genetics inferences. GF risk was evaluated using Cox proportional-hazards regression models adjusted for covariates including patient and donor risk factors and HLA antigen MMs. Results We show that estimated AA MMs at particular positions in the peptide-binding pockets of HLA-DRB1 molecule account for a significant incremental risk that was independent of the well-known association of HLA antigen MMs with graft survival. A statistically significant linear relationship between the estimated number of AA MMs and risk of GF was observed for HLA-DRB1 in deceased donor and living donor transplants. This relationship was strongest during the first 12 months after transplantation (hazard ratio, 1.30 per 15 DRB1 AA MM; P < 0.0001). Conclusions This study shows that independent of the well-known association of HLA antigen (2-digit specificity) MMs with kidney graft survival, estimated AA MMs at peptide-binding sites of the HLA-DRB1 molecule account for an important incremental risk of GF. PMID:28221244

A Continuous Flow Column Study of Anaerobic PCE Transformation With the Evanite Culture and Hanford Aquifer Solids

NASA Astrophysics Data System (ADS)

Semprini, L.; Behrens, S.; Azizian, M.; Sabalowsky, A.; Dolan, M.; Ruiz-Hass, P.; Ingle, J.; Spormann, A.

2005-12-01

Anaerobic reductive dehalogenation of tetrachloroethene (PCE) and trichoroethene (TCE) is a promising technology for the in situ treatment of high concentration source zones in contaminated aquifers. Continuous flow column studies were performed where a mixed dehalogenating culture (Evanite culture) that contains Dehalococcides-like microorganisms was bioaugmented into aquifer solids from the Hanford DOE site. Studies conducted prior to bioaugmentation showed PCE transport was retarded due to sorption onto the aquifer solids. Upon bioaugmentation and with continuous lactate addition, PCE (10 mg/L) was transformed to cis-dichloroethene ( cis-DCE), and enhanced transformation of sorbed PCE was observed. Prolonged production of cis-DCE was associated with iron reducing conditions, while eventual vinyl chloride (VC) reduction to ethene was associated with sulfate reducing conditions. Microbial processes included lactate fermentation to acetate and propionate, iron reduction, sulfate reduction, and reductive dehalogenation, with reductive dehalogenation utilizing 2 to 3% of the electron donor addition. PCE was completely transformed to ethene within a hydraulic residence time of one day. Upon competition of the column tests spatial samples of aquifer solids were analyzed using molecular methods and solids were used in batch microcosm activity tests. Dehalococcoides sp. 16S rRNA gene copy numbers dropped from ~ 74% of total Eubacterial 16S rRNA genes in the original inoculum, to about 0.5 to 4% through out the column, consistent with the estimates of electron donor utilization for dehalogenation reactions. Microcosm tests showed most of PCE transformation activity at the entrance of the column, consistent with the Dehalococcoides sp. 16S rRNA gene copy numbers being highest in that area. Roughly 20% of the Dehalococcoides sp. population in the column possessed a vcrA gene for the respiration of VC to ethene. The vcrA-positive subpopulation decreases to about 5% towards the column outflow, while VC microcosm activity tests show fairly constant rates of VC transformation across the column. The column studies demonstrated that complete transformation of PCE to ethene can be obtained over short spatial and temporal scales.

Evaluation of Methods Used for Estimating Selected Streamflow Statistics, and Flood Frequency and Magnitude, for Small Basins in North Coastal California

USGS Publications Warehouse

Mann, Michael P.; Rizzardo, Jule; Satkowski, Richard

2004-01-01

Accurate streamflow statistics are essential to water resource agencies involved in both science and decision-making. When long-term streamflow data are lacking at a site, estimation techniques are often employed to generate streamflow statistics. However, procedures for accurately estimating streamflow statistics often are lacking. When estimation procedures are developed, they often are not evaluated properly before being applied. Use of unevaluated or underevaluated flow-statistic estimation techniques can result in improper water-resources decision-making. The California State Water Resources Control Board (SWRCB) uses two key techniques, a modified rational equation and drainage basin area-ratio transfer, to estimate streamflow statistics at ungaged locations. These techniques have been implemented to varying degrees, but have not been formally evaluated. For estimating peak flows at the 2-, 5-, 10-, 25-, 50-, and 100-year recurrence intervals, the SWRCB uses the U.S. Geological Surveys (USGS) regional peak-flow equations. In this study, done cooperatively by the USGS and SWRCB, the SWRCB estimated several flow statistics at 40 USGS streamflow gaging stations in the north coast region of California. The SWRCB estimates were made without reference to USGS flow data. The USGS used the streamflow data provided by the 40 stations to generate flow statistics that could be compared with SWRCB estimates for accuracy. While some SWRCB estimates compared favorably with USGS statistics, results were subject to varying degrees of error over the region. Flow-based estimation techniques generally performed better than rain-based methods, especially for estimation of December 15 to March 31 mean daily flows. The USGS peak-flow equations also performed well, but tended to underestimate peak flows. The USGS equations performed within reported error bounds, but will require updating in the future as peak-flow data sets grow larger. Little correlation was discovered between estimation errors and geographic locations or various basin characteristics. However, for 25-percentile year mean-daily-flow estimates for December 15 to March 31, the greatest estimation errors were at east San Francisco Bay area stations with mean annual precipitation less than or equal to 30 inches, and estimated 2-year/24-hour rainfall intensity less than 3 inches.

Peak-flow characteristics of Virginia streams

USGS Publications Warehouse

Austin, Samuel H.; Krstolic, Jennifer L.; Wiegand, Ute

2011-01-01

Peak-flow annual exceedance probabilities, also called probability-percent chance flow estimates, and regional regression equations are provided describing the peak-flow characteristics of Virginia streams. Statistical methods are used to evaluate peak-flow data. Analysis of Virginia peak-flow data collected from 1895 through 2007 is summarized. Methods are provided for estimating unregulated peak flow of gaged and ungaged streams. Station peak-flow characteristics identified by fitting the logarithms of annual peak flows to a Log Pearson Type III frequency distribution yield annual exceedance probabilities of 0.5, 0.4292, 0.2, 0.1, 0.04, 0.02, 0.01, 0.005, and 0.002 for 476 streamgaging stations. Stream basin characteristics computed using spatial data and a geographic information system are used as explanatory variables in regional regression model equations for six physiographic regions to estimate regional annual exceedance probabilities at gaged and ungaged sites. Weighted peak-flow values that combine annual exceedance probabilities computed from gaging station data and from regional regression equations provide improved peak-flow estimates. Text, figures, and lists are provided summarizing selected peak-flow sites, delineated physiographic regions, peak-flow estimates, basin characteristics, regional regression model equations, error estimates, definitions, data sources, and candidate regression model equations. This study supersedes previous studies of peak flows in Virginia.

Innate inflammatory gene expression profiling in potential brain-dead donors: detailed investigation of the effect of common corticosteroid therapy.

PubMed

Gholamnezhadjafari, Reza; Tajik, Nader; Falak, Reza; Aflatoonian, Reza; Dehghan, Sanaz; Rezaei, Abbas

2017-07-01

Our study aimed to assess the influence of common methylprednisolone therapy on innate inflammatory factors in potential brain-dead organ donors (BDDs). The study groups consisted of 50 potential BDDs who received 15 mg/kg/d methylprednisolone and 25 live organ donors (LDs) as control group. Innate immunity gene expression profiling was performed by RT-PCR array. Soluble serum cytokines and chemokines, complement components, heat shock protein 70 (HSP70) and high mobility group box-1 (HMGB1) were measured by ELISA. Surface expression of TLR2 and TLR4 were determined using flow cytometry. Gene expression profiling revealed up-regulation of TLRs 1, 2, 4, 5, 6, 7 and 8, MYD88, NF-κB, NF-κB1A, IRAK1, STAT3, JAK2, TNF-α, IL-1β, CD86 and CD14 in the BDD group. Remarkably, the serum levels of C-reactive protein and HSP70 were considerably higher in the BDD group. In addition, serum amounts of IL-1β, IL-6, TNF-α, HMGB1, HSP70, C3a and C5a, but not IL-8, sCD86 or monocyte chemoattractant protein-1, were significantly increased in the BDD group. Significant differences were observed in flow cytometry analysis of TLR2 and TLR4 between the two groups. In summary, common methylprednisolone therapy in BDDs did not adequately reduce systemic inflammation, which could be due to inadequate doses or inefficient impact on other inflammatory-inducing pathways, for example oxidative stress or production of damage-associated molecules.

N-octanoyl-dopamine is a potent inhibitor of platelet function.

PubMed

Ait-Hsiko, Lamia; Kraaij, Tineke; Wedel, Johannes; Theisinger, Bastian; Theisinger, Sonja; Yard, Benito; Bugert, Peter; Schedel, Angelika

2013-01-01

Dopamine (DA) is a co-agonist for platelet activation; yet, donor DA treatment is associated with improved transplantation outcome in renal and heart recipients. Recently, N-octanoyl-dopamine (NOD) was developed which displays superior effects compared to DA in terms of graft protecting properties. Whereas DA is a known platelet co-agonist, the effect of NOD on platelet function is unknown. This is a hypothesis generating study with the aim to assess the effects and molecular mechanisms of NOD and NOD-like compounds on platelet function. The influence of DA, NOD, and NOD-like compounds on platelet responses to classical agonists (adenosine 5'-diphosphate (ADP), U46619) was investigated in six healthy donors by applying whole blood aggregometry (Multiplate®) and flow cytometry for Pac-1, CD62P, and CD63 expression. Changes in platelet cAMP concentrations were assessed by ELISA. While DA showed synergy in platelet activation by ADP and U46619, NOD caused significant inhibition of platelet function both in whole blood aggregometry and flow cytometry. The inhibitory effect of NOD was not mediated via cAMP levels. The nonredox-active NOD-analog N-octanoyl-tyramine had no effects on platelet function. Acetylated NOD conferred to NOD by intracellular esterases showed similar inhibitory effects as NOD. In contrast to DA, NOD is a potent inhibitor of platelet function most likely through intracellular redox-active processes. This adds to the overall protective effect of NOD on pre-transplantation injury and makes NOD an attractive candidate compound for donor or organ conditioning prior to transplantation.

Production and Consumption of Hydrogen in Hot Spring Microbial Mats Dominated by a Filamentous Anoxygenic Photosynthetic Bacterium

PubMed Central

Otaki, Hiroyo; Everroad, R. Craig; Matsuura, Katsumi; Haruta, Shin

2012-01-01

Microbial mats containing the filamentous anoxygenic photosynthetic bacterium Chloroflexus aggregans develop at Nakabusa hot spring in Japan. Under anaerobic conditions in these mats, interspecies interaction between sulfate-reducing bacteria as sulfide producers and C. aggregans as a sulfide consumer has been proposed to constitute a sulfur cycle; however, the electron donor utilized for microbial sulfide production at Nakabusa remains to be identified. In order to determine this electron donor and its source, ex situ experimental incubation of mats was explored. In the presence of molybdate, which inhibits biological sulfate reduction, hydrogen gas was released from mat samples, indicating that this hydrogen is normally consumed as an electron donor by sulfate-reducing bacteria. Hydrogen production decreased under illumination, indicating that C. aggregans also functions as a hydrogen consumer. Small amounts of hydrogen may have also been consumed for sulfur reduction. Clone library analysis of 16S rRNA genes amplified from the mats indicated the existence of several species of hydrogen-producing fermentative bacteria. Among them, the most dominant fermenter, Fervidobacterium sp., was successfully isolated. This isolate produced hydrogen through the fermentation of organic carbon. Dispersion of microbial cells in the mats resulted in hydrogen production without the addition of molybdate, suggesting that simultaneous production and consumption of hydrogen in the mats requires dense packing of cells. We propose a cyclic electron flow within the microbial mats, i.e., electron flow occurs through three elements: S (elemental sulfur, sulfide, sulfate), C (carbon dioxide, organic carbon) and H (di-hydrogen, protons). PMID:22446313

Centrally Determined Standardization of Flow Cytometry Methods Reduces Interlaboratory Variation in a Prospective Multicenter Study

PubMed Central

Westera, Liset; van Viegen, Tanja; Jeyarajah, Jenny; Azad, Azar; Bilsborough, Janine; van den Brink, Gijs R; Cremer, Jonathan; Danese, Silvio; D'Haens, Geert; Eckmann, Lars; Faubion, William; Filice, Melissa; Korf, Hannelie; McGovern, Dermot; Panes, Julian; Salas, Azucena; Sandborn, William J; Silverberg, Mark S; Smith, Michelle I; Vermeire, Severine; Vetrano, Stefania; Shackelton, Lisa M; Stitt, Larry; Jairath, Vipul; Levesque, Barrett G; Spencer, David M; Feagan, Brian G; Vande Casteele, Niels

2017-01-01

Objectives: Flow cytometry (FC) aids in characterization of cellular and molecular factors involved in pathologic immune responses. Although FC has potential to facilitate early drug development in inflammatory bowel disease, interlaboratory variability limits its use in multicenter trials. Standardization of methods may address this limitation. We compared variability in FC-aided quantitation of T-cell responses across international laboratories using three analytical strategies. Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from three healthy donors, stimulated with phorbol 12-myristate 13-acetate and ionomycin at a central laboratory, fixed, frozen, and shipped to seven international laboratories. Permeabilization and staining was performed in triplicate at each laboratory using a common protocol and centrally provided reagents. Gating was performed using local gating with a local strategy (LGLS), local gating with a central strategy (LGCS), and central gating (CG). Median cell percentages were calculated across triplicates and donors, and reported for each condition and strategy. The coefficient of variation (CV) was calculated across laboratories. Between-strategy comparisons were made using a two-way analysis of variance adjusting for donor. Results: Mean interlaboratory CV ranged from 1.8 to 102.1% depending on cell population and gating strategy (LGLS, 4.4–102.1% LGCS, 10.9–65.6% CG, 1.8–20.9%). Mean interlaboratory CV differed significantly across strategies and was consistently lower with CG. Conclusions: Central gating was the only strategy with mean CVs consistently lower than 25%, which is a proposed standard for pharmacodynamic and exploratory biomarker assays. PMID:29095427

Electrical Manipulation of Spin Qubits in Li-doped Si

NASA Astrophysics Data System (ADS)

Petukhov, Andre; Pendo, Luke; Handberg, Erin; Smelyanskiy, Vadim

2011-03-01

We propose a complete quantum computing scheme based on Li donors in Si under external biaxial stress. The qubits are encoded on the ground state Zeeman doublets and coupled via long-range spin-spin interaction mediated by acoustic phonons. This interaction is unique for Li donors in Si due to their inverted electronic structure. Our scheme takes advantage of the fact that the energy level spacing in 1 s Li-donor manifold is comparable with the magnitude of the spin-orbit interaction. As a result the Li spin qubits can be placed 100 nm apart and manipulated by a combination of external electric field and microwave field impulses. We present a specially-designed sequence of the electric field impulses which allows for a typical time of a two-qubit gate ~ ~1~ μ s and a quality factor ~10-6 . These estimates are derived from detailed microscopic calculations of the quadratic Stark effect and electron-phonon decoherence times.

The effect of memory in the stochastic master equation analyzed using the stochastic Liouville equation of motion. Electronic energy migration transfer between reorienting donor-donor, donor-acceptor chromophores

NASA Astrophysics Data System (ADS)

Håkansson, Pär; Westlund, Per-Olof

2005-01-01

This paper discusses the process of energy migration transfer within reorientating chromophores using the stochastic master equation (SME) and the stochastic Liouville equation (SLE) of motion. We have found that the SME over-estimates the rate of the energy migration compared to the SLE solution for a case of weakly interacting chromophores. This discrepancy between SME and SLE is caused by a memory effect occurring when fluctuations in the dipole-dipole Hamiltonian ( H( t)) are on the same timescale as the intrinsic fast transverse relaxation rate characterized by (1/ T2). Thus the timescale critical for energy-transfer experiments is T2≈10 -13 s. An extended SME is constructed, accounting for the memory effect of the dipole-dipole Hamiltonian dynamics. The influence of memory on the interpretation of experiments is discussed.

Continuous-flow column study of reductive dehalogenation of PCE upon bioaugmentation with the Evanite enrichment culture

NASA Astrophysics Data System (ADS)

Azizian, Mohammad F.; Behrens, Sebastian; Sabalowsky, Andrew; Dolan, Mark E.; Spormann, Alfred M.; Semprini, Lewis

2008-08-01

A continuous-flow anaerobic column experiment was conducted to evaluate the reductive dechlorination of tetrachloroethene (PCE) in Hanford aquifer material after bioaugmentation with the Evanite (EV) culture. An influent PCE concentration of 0.09 mM was transformed to vinyl chloride (VC) and ethene (ETH) within a hydraulic residence time of 1.3 days. The experimental breakthrough curves were described by the one-dimensional two-site-nonequilibrium transport model. PCE dechlorination was observed after bioaugmentation and after the lactate concentration was increased from 0.35 to 0.67 mM. At the onset of reductive dehalogenation, cis-dichloroethene (c-DCE) concentrations in the column effluent exceeded the influent PCE concentration indicating enhanced PCE desorption and transformation. When the lactate concentration was increased to 1.34 mM, c-DCE reduction to vinyl chloride (VC) and ethene (ETH) occurred. Spatial rates of PCE and VC transformation were determined in batch-incubated microcosms constructed with aquifer samples obtained from the column. PCE transformation rates were highest in the first 5 cm from the column inlet and decreased towards the column effluent. Dehalococcoides cell numbers dropped from ˜ 73.5% of the total Bacterial population in the original inocula, to about 0.5% to 4% throughout the column. The results were consistent with estimates of electron donor utilization, with 4% going towards dehalogenation reactions.

A nitric oxide donor reduces brain injury and enhances recovery of cerebral blood flow after hypoxia-ischemia in the newborn rat.

PubMed

Wainwright, Mark S; Grundhoefer, Dava; Sharma, Shruti; Black, Stephen M

2007-03-26

Nitric oxide (NO) released in response to hypoxia-ischemia (HI) in the newborn brain may mediate both protective and pathologic responses. We sought to determine whether pharmacologic increase of NO using an NO donor would reduce neurologic injury resulting from HI in the postnatal day 7 rat. We measured NO levels and CBF in the presence of either a NOS inhibitor, N-nitro-l-arginine methyl ester (L-NAME) or an NO donor (Z)-1-[N-(2-amino-ethyl)-N-(2-ammonio-ethyl)amino]diazen-1-ium-1,2-diolate (DETANONOate). Both inhibition of NOS and administration of an NO donor reduced neuropathologic injury after 7-day recovery. NO levels decreased in both ischemic and contralateral hemispheres during HI. This response was prevented by treatment with DETANONOate. Despite the decrease in NO, CBF increased during ischemia in the contralateral hemisphere but decreased when combined with brief hypoxia. Treatment with L-NAME abolished these increases, which were not altered by DETANONOate. Reduction of cellular metabolism by mild hypothermia also reduced both NO and CBF. Following prolonged HI, CBF remained decreased in the ischemic hemisphere up to 24-h recovery. This decrease was prevented by treatment with DETANONOate. These data show that administration of an NO donor reduces neurologic injury following HI in the newborn rat. This mechanism of this protection, in part, is due to an increase in the rate of recovery of CBF compared to vehicle-treated animals. Augmentation of NO-dependent increases in CBF may serve to improve neurologic outcome after perinatal asphyxia.

A NITRIC OXIDE DONOR REDUCES BRAIN INJURY AND ENHANCES RECOVERY OF CEREBRAL BLOOD FLOW AFTER HYPOXIA-ISCHEMIA IN THE NEWBORN RAT

PubMed Central

Wainwright, Mark S.; Grundhoefer, Dava; Sharma, Shruti; Black, Stephen M.

2007-01-01

Nitric oxide (NO) released in response to hypoxia-ischemia (HI) in the newborn brain may mediate both protective and pathologic responses. We sought to determine whether pharmacologic increase of NO using an NO donor would reduce neurologic injury resulting from HI in the postnatal day 7 rat. We measured NO levels and CBF in the presence of either a NOS inhibitor, N-nitro-L-arginine methyl ester (L-NAME) or an NO donor (Z)-1-[N-(2aminoethyl)-N-(2-ammonio-ethyl)amino]diazen-1-ium-1,2-diolate (DETANONOate). Both inhibition of NOS and administration of an NO donor reduced neuropathologic injury after 7-day recovery. NO levels decreased in both ischemic and contralateral hemispheres during HI. This response was prevented by treatment with DETANONOate. Despite the decrease in NO, CBF increased during ischemia in the contralateral hemisphere but decreased when combined with brief hypoxia. Treatment with L-NAME abolished these increases, which were not altered by DETANONOate. Reduction of cellular metabolism by mild hypothermia also reduced both NO and CBF. Following prolonged HI, CBF remained decreased in the ischemic hemisphere up to 24-hour recovery. This decrease was prevented by treatment with DETANONOate. These data show that administration of an NO donor reduces neurologic injury following HI in the newborn rat. This mechanism of this protection, in part, is due to an increase in the rate of recovery of CBF compared to vehicle-treated animals. Augmentation of NO-dependent increases in CBF may serve to improve neurologic outcome after perinatal asphyxia. PMID:17270345

Interaction of non-human primate complement and antibodies with hypermucoviscous Klebsiella pneumoniae.

PubMed

Soto, Esteban; Marchi, Sylvia; Beierschmitt, Amy; Kearney, Michael; Francis, Stewart; VanNess, Kimberly; Vandenplas, Michel; Thrall, MaryAnna; Palmour, Roberta

2016-03-08

Emergent hypermucoviscosity (HMV) phenotypes of Klebsiella pneumoniae have been associated with increased invasiveness and pathogenicity in primates. In this study, we investigated the interaction of African green monkeys (AGM) (Chlorocebus aethiops sabaeus) complement and antibody with HMV and non-HMV isolates as in vitro models of primate infection. Significantly greater survival of HMV isolates was evident after incubation in normal serum or whole blood (p < 0.05) of AGM donors when compared to non-HMV strains. Greater survival of HMV strains (p < 0.05) was found after incubation in whole blood and serum from seropositive donors when compared to seronegative donor samples. Additionally, significantly greater amounts of K. pneumoniae were phagocytozed by AGM leukocytes when complement was active (p < 0.05), but no difference in uptake was observed when serum from seropositive or seronegative animals was used in challenged cells utilizing flow cytometry. Results demonstrate that interaction of cellular and humoral immune elements play a role in the in vitro killing of K. pneumoniae, particularly HMV isolates. Neither AGM serum, nor washed whole blood effectively killed HMV isolates; however, assays using heparinized whole blood of seronegative donors significantly reduced viability of HMV and non-HMV strains. The lack of bacterial killing observed in seropositive donors treatments could be at least partially associated with low IgG2 present in these animals. A better understanding of the pathogenesis of klebsiellosis in primates and host immune response is necessary to identify surface molecules that can induce both opsonizing and bactericidal antibody facilitating killing of Klebsiella, and the development of vaccines in human and animals.

G-CSF-primed autologous and allogeneic bone marrow for transplantation in clinical oncology. Cell content and immunological characteristics

NASA Astrophysics Data System (ADS)

Grivtsova, L. Yu; Melkova, K. N.; Kupryshkina, N. A.; Vorotnikov, I. K.; Grigoryeva, T. A.; Selchuk, V. Yu; Grebennikova, O. P.; Titova, G. V.; Tupitsyn, N. N.

2018-01-01

60 samples of G-CSF-primed bone marrow (39 cancer patients and 21 healthy donors) to be used for transplantation to cancer patients were analyzed and compared by main characteristics with historical control and 13 bone marrow samples from control patient with mastopathy. Basing on morphological and multicolor flow cytometry findings certain characteristics of G-CSF-primed bone marrow were discovered, such as a significant increase in blast count in cancer patients as compared to donors and control patients (p<0.037), a higher neutrophil maturation index (p<0.001) and a lower percentage of mature lymphocytes (p<0.008) as compared to the control group. Among lymphocyte populations G-CSF-priming was associated with a significant increase in the total of mature CD3+ T-cells and CD8+ T-killers (p<0.0001) and a decrease in CD56+CD3- and/or CD16+CD3- NK-cells (p<0.006) both in cancer patients and healthy donors in comparison with the controls.

Comparative Analysis of Various Aspects of Plateletpheresis on the Fenwal Amicus and Fresenius COM.TEC Cell Separator Instruments.

PubMed

Philip, Joseph; Biswas, Amit Kumar; Chatterjee, Tathagata; Mallhi, Rajiv Singh

2014-01-01

To compare the Fenwal Amicus and the Fresenius COM.TEC apheresis instruments regarding donor peripheral blood parameters, operational variables of the instruments, and quality control parameters of the product obtained. We performed 100 platelet collections from 100 voluntary donors using the 2 studied devices. We measured platelet count using an automated analyzer and analyzed the activation statuses using a flow cytometer. The median time needed to perform the procedures was significantly longer with the COM.TEC. However, the product we obtained using the Amicus instrument showed higher degrees of platelet-activation. All products we obtained with both instruments had white blood cell counts of less than 5 × 10(6) per bag. We observed no statistical difference regarding collection efficiency and collection rates between the devices. Both instruments collected platelets efficiently, with minimal donor discomfort. Compared with the COM.TEC instrument, the Amicus reached the platelet target yield more quickly; however, it displayed an increase in platelet activation. Copyright© by the American Society for Clinical Pathology (ASCP).

Predicting performance for ecological restoration: A case study using Spartina altemiflora

USGS Publications Warehouse

Travis, S.E.; Grace, J.B.

2010-01-01

The success of population-based ecological restoration relies on the growth and reproductive performance of selected donor materials, whether consisting of whole plants or seed. Accurately predicting performance requires an understanding of a variety of underlying processes, particularly gene flow and selection, which can be measured, at least in part, using surrogates such as neutral marker genetic distances and simple latitudinal effects. Here we apply a structural equation modeling approach to understanding and predicting performance in a widespread salt marsh grass, Spartina alterniflora, commonly used for ecological restoration throughout its native range in North America. We collected source materials from throughout this range, consisting of eight clones each from 23 populations, for transplantation to a common garden site in coastal Louisiana and monitored their performance. We modeled performance as a latent process described by multiple indicator variables (e.g., clone diameter, stem number) and estimated direct and indirect influences of geographic and genetic distances on performance. Genetic distances were determined by comparison of neutral molecular markers with those from a local population at the common garden site. Geographic distance metrics included dispersal distance (the minimum distance over water between donor and experimental sites) and latitude. Model results indicate direct effects of genetic distance and latitude on performance variation among the donor sites. Standardized effect strengths indicate that performance was roughly twice as sensitive to variation in genetic distance as to latitudinal variation. Dispersal distance had an indirect influence on performance through effects on genetic distance, indicating a typical pattern of genetic isolation by distance. Latitude also had an indirect effect on genetic distance through its linear relationship with dispersal distance. Three performance indicators had significant loadings on performance alone (mean clone diameter, mean number of stems, mean number of inflorescences), while the performance indicators mean stem height and mean stem width were also influenced by latitude. We suggest that dispersal distance and latitude should provide an adequate means of predicting performance in future S. alterniflora restorations and propose a maximum sampling distance of 300 km (holding latitude constant) to avoid the sampling of inappropriate ecotypes. ?? 2010 by the Ecological Society of America.

How I do it: combined direct (STA-MCA) and indirect (EDAS) EC-IC bypass.

PubMed

Nossek, Erez; Langer, David J

2014-11-01

EC-IC bypass for the treatment of a hypoperfused hemisphere is currently the treatment of choice for symptomatic moyamoya patients. Use of the combination of direct (STA-MCA) and indirect (an STA branch lay-on bypass and flipped dural flaps; EDAS) EC-IC bypass is advocated as the optimal treatment option as it allows immediate augmentation of flow in the postoperative period while allowing the brain to acquire additional indirect flow in the long term. We describe the technical nuances of a combined direct and indirect bypass in a 41-year-old woman with moyamoya syndrome diagnosed with transient ischemic attacks (TIAs) and cognitive decline. Combined direct and indirect bypass option should become a familiar treatment modality among vascular neurosurgeons. (1) Pay critical attention to not injuring the Superficial Temporal Artery, Parietal branch (STApb) while turning the skin incision anteriorly. Use the operating microscope to dissect the STApb. (2) Always mark the origin of the Superficial Temporal Artery, Frontal branch (STAfb) on the skin so that its location can be anticipated during STApb dissection. (3) When no frontal branch is available or if the frontal branch is of poor quality, the STApb can be used as a direct or indirect graft. (4) A craniotomy should be done 2-3 cm posterior to the course of the STApb to allow for adequate exposure for an indirect graft. (5) Manipulation of the donor vessels should be done with extreme care as spasm of the artery or intraluminal thrombosis may occur. Low cut flow in the direct graft should be interpreted with caution as vasospasm can result in significant temporary reduction of flow. (6) Aggressive distal dissection of the direct donor is a must. The distal 1-2 cm of the vessel should be cleaned of any loose tissue and be fishmouthed prior to anastomosis. (7) A blood-free field is mandatory. Perforators on the backside of the recipient should be sacrificed and cut to avoid backbleeding into the anastomotic segment during temporary occlusion. (8) When recirculating after the anastomosis has been completed, open the temporary clips on the recipient first. Backflow into the donor segment confirms a patent anastomosis. (9) Utilization of intraoperative angiography is not necessary as long as one utilizes flow measurements and ICG angiography. (10) Take great care with the bone flap reconstruction and the skin closure as the grafts can easily be compressed or sutured. Create a generous craniectomy in the bone flap to avoid any graft compression.

Nitric oxide in the nucleus raphe magnus modulates cutaneous blood flow in rats during hypothermia.

PubMed

Arami, Masoumeh Kourosh; Zade, Javad Mirnajafi; Komaki, Alireza; Amiri, Mahmood; Mehrpooya, Sara; Jahanshahi, Ali; Jamei, Behnam

2015-10-01

Nucleus Raphe Magnus (NRM) that is involved in the regulation of body temperature contains nitric oxide (NO) synthase. Considering the effect of NO on skin blood flow control, in this study, we assessed its thermoregulatory role within the raphe magnus. To this end, tail blood flow of male Wistar rats was measured by laser doppler following the induction of hypothermia. Intra-NRM injection of SNP (exogenous NO donor, 0.1- 0.2 μl, 0.2 nM) increased the blood flow. Similarly, unilateral microinjection of glutamate (0.1- 0.2 μl, 2.3 nM) into the nucleus increased the blood flow. This effect of L-glutamate was reduced by prior intra NRM administration of NO synthase inhibitor N(G)-methyl-L-arginine or N(G)-nitro-L-arginine methyl ester (L-NAME, 0.1 µl, 100 nM). It is concluded that NO modulates the thermoregulatory response of NRM to hypothermia and may interact with excitatory amino acids in central skin blood flow regulation.

ABO, Rhesus, and Kell Antigens, Alleles, and Haplotypes in West Bengal, India

PubMed Central

Basu, Debapriya; Datta, Suvro Sankha; Montemayor, Celina; Bhattacharya, Prasun; Mukherjee, Krishnendu; Flegel, Willy A.

2018-01-01

Background Few studies have documented the blood group antigens in the population of eastern India. Frequencies of some common alleles and haplotypes were unknown. We describe phenotype, allele, and haplotype frequencies in the state of West Bengal, India. Methods We tested 1,528 blood donors at the Medical College Hospital, Kolkata. The common antigens of the ABO, Rhesus, and Kell blood group systems were determined by standard serologic methods in tubes. Allele and haplotype frequencies were calculated with an iterative method that yielded maximum-likelihood estimates under the assumption of a Hardy-Weinberg equilibrium. Results The prevalence of ABO antigens were B (34%), O (32%), A (25%), and AB (9%) with ABO allele frequencies for O = 0.567, A = 0.189, and B = 0.244. The D antigen (RH1) was observed in 96.6% of the blood donors with RH haplotype frequencies, such as for CDe = 0.688809, cde = 0.16983 and CdE = 0.000654. The K antigen (K1) was observed in 12 donors (0.79%) with KEL allele frequencies for K = 0.004 and k = 0.996. Conclusions: For the Bengali population living in the south of West Bengal, we established the frequencies of the major clinically relevant antigens in the ABO, Rhesus, and Kell blood group systems and derived estimates for the underlying ABO and KEL alleles and RH haplotypes. Such blood donor screening will improve the availability of compatible red cell units for transfusion. Our approach using widely available routine methods can readily be applied in other regions, where the sufficient supply of blood typed for the Rh and K antigens is lacking. PMID:29593462

Inbreeding effects on in vitro embryo production traits in Guzerá cattle.

PubMed

Perez, B C; Balieiro, J C C; Ventura, R V; Bruneli, F A T; Peixoto, M G C D

2017-11-01

Inbreeding has been associated with the impairment of reproductive performance in many cattle breeds. Although the usage of reproductive biotechnologies has been increasing in bovine populations, not much attention has been given to the impact of inbreeding over cow's performance on artificial reproduction. The objective of this study was to estimate the impact of inbreeding on in vitro embryo production in a Guzerá breed population. The inbreeding coefficient (F), calculated as half of the co-ancestry of the individual's parents, was used as an estimate of inbreeding. The inbreeding coefficients of the donor, sire (used on in vitro fertilization) and of the embryos were included, separately, in the proposed models either as classificatory or continuous variables (linear and quadratic effects). The percentage of non-inbred individuals (or embryos) and mean F of donors, embryos and sires were 29.38%; 35.76%; 42.86% and 1.98±2.68; 1.32±3.13; 2.08±2.79, respectively. Two different models were considered, one for oocyte production traits and other for embryo production traits. The increase of F of the donor significantly (P<0.05) impaired the number of viable oocytes (N OV), number of grade I oocytes (N GI) and number of cleaved embryos (N CLV). Moreover, the donor's F influenced the percentage of grade I oocytes (P GI), percentage of viable embryos (P EMB) and percentage of cleaved embryos that turned into embryos (P CXE). No significant (P>0.05) effects were observed for the sire (father of the embryos) inbreeding coefficient over the traits analysed. Embryo's F influenced (P<0.05) the number of viable embryos (N EMB), percentage of viable embryos (P EMB) and percentage of cleaved embryos that turn into embryos (P CXE). Results suggested that an increase in the inbreeding coefficient might impair the embryos ability to survive through challenges imposed by the in vitro environment. Submitting highly inbred Guzerá female donors to in vitro embryo production may, in the long-term, have negative implications on the number of embryos obtained per cow and increase the relative costs of the improvement programmes based on this technology. High levels of inbreeding should be avoided when selecting Guzerá female donors and planning in vitro fertilization mating.

Analysis of evolutionary rate of HIV-1 subtype B using blood donor samples in Japan.

PubMed

Shinohara, Naoya; Matsumoto, Chieko; Matsubayashi, Keiji; Nagai, Tadashi; Satake, Masahiro

2018-06-01

There are few reports on HIV-1 intra-host evolutionary rate in asymptomatic treatment-naïve patients. Here, the HIV-1 intra-host evolutionary rate was estimated based on HIV-1 RNA sequences from plasma samples of blood donors in Japan. Blood donors were assumed to have received no treatment for and have no symptoms of HIV-1 infection because they were healthy, and declared no risky behaviors of HIV-1 infection on a self-reported questionnaire or interview followed by donation. HIV-1 RNA was obtained from 85 plasma samples from 36 blood donors who donated blood multiple times and were HIV-1-positive. The C2V3C3 region which encodes for a part of the envelope protein, and the V3 loop in the C2V3C3 region were analyzed by RT-PCR and direct sequencing, and the sequences were compared. The nucleotide substitution rate was calculated by linear regression. All HIV-1 samples analyzed were classified as subtype B. The mean nucleotide substitution rate in C2V3C3 was calculated to be 6.2 × 10 -3 -1.8 × 10 -2 /site/year (V3: 4.5 × 10 -3 -2.3 × 10 -2 /site/year). The mean non-synonymous substitution rate in C2V3C3 was calculated to be 5.2 × 10 -3 -1.7 × 10 -2 /site/year (V3: 4.5 × 10 -3 -2.1 × 10 -2 /site/year). The mean synonymous substitution rate in C2V3C3 was calculated to be 1.1 × 10 -4 -2.3 × 10 -3 /site/year (V3: 2.9 × 10 -3 /site/year). Among HIV-1 subtype B RNA-positive blood donors in Japan, the nucleotide substitution rate in C2V3C3 was estimated to be higher than that of reported cases using HIV-1 samples mainly obtained from AIDS patients. Compared to AIDS patients, immune responses against HIV-1 are probably more effective in HIV-1 RNA-positive blood donors. Consequently, immune pressure presumably promotes mutation of the virus genome.

Differential microRNA Expression between Asthmatic and Healthy Donors

EPA Science Inventory

Introduction: Asthma is a chronic lung disease and is pathologically characterized by increases in bronchial hyperresponsiveness and chronic inflammation. It is estimated to affect approximately 300 million people worldwide and cases are expected to continually rise over the next...

Estimation of selected streamflow statistics for a network of low-flow partial-record stations in areas affected by Base Realignment and Closure (BRAC) in Maryland

USGS Publications Warehouse

Ries, Kernell G.; Eng, Ken

2010-01-01

The U.S. Geological Survey, in cooperation with the Maryland Department of the Environment, operated a network of 20 low-flow partial-record stations during 2008 in a region that extends from southwest of Baltimore to the northeastern corner of Maryland to obtain estimates of selected streamflow statistics at the station locations. The study area is expected to face a substantial influx of new residents and businesses as a result of military and civilian personnel transfers associated with the Federal Base Realignment and Closure Act of 2005. The estimated streamflow statistics, which include monthly 85-percent duration flows, the 10-year recurrence-interval minimum base flow, and the 7-day, 10-year low flow, are needed to provide a better understanding of the availability of water resources in the area to be affected by base-realignment activities. Streamflow measurements collected for this study at the low-flow partial-record stations and measurements collected previously for 8 of the 20 stations were related to concurrent daily flows at nearby index streamgages to estimate the streamflow statistics. Three methods were used to estimate the streamflow statistics and two methods were used to select the index streamgages. Of the three methods used to estimate the streamflow statistics, two of them--the Moments and MOVE1 methods--rely on correlating the streamflow measurements at the low-flow partial-record stations with concurrent streamflows at nearby, hydrologically similar index streamgages to determine the estimates. These methods, recommended for use by the U.S. Geological Survey, generally require about 10 streamflow measurements at the low-flow partial-record station. The third method transfers the streamflow statistics from the index streamgage to the partial-record station based on the average of the ratios of the measured streamflows at the partial-record station to the concurrent streamflows at the index streamgage. This method can be used with as few as one pair of streamflow measurements made on a single streamflow recession at the low-flow partial-record station, although additional pairs of measurements will increase the accuracy of the estimates. Errors associated with the two correlation methods generally were lower than the errors associated with the flow-ratio method, but the advantages of the flow-ratio method are that it can produce reasonably accurate estimates from streamflow measurements much faster and at lower cost than estimates obtained using the correlation methods. The two index-streamgage selection methods were (1) selection based on the highest correlation coefficient between the low-flow partial-record station and the index streamgages, and (2) selection based on Euclidean distance, where the Euclidean distance was computed as a function of geographic proximity and the basin characteristics: drainage area, percentage of forested area, percentage of impervious area, and the base-flow recession time constant, t. Method 1 generally selected index streamgages that were significantly closer to the low-flow partial-record stations than method 2. The errors associated with the estimated streamflow statistics generally were lower for method 1 than for method 2, but the differences were not statistically significant. The flow-ratio method for estimating streamflow statistics at low-flow partial-record stations was shown to be independent from the two correlation-based estimation methods. As a result, final estimates were determined for eight low-flow partial-record stations by weighting estimates from the flow-ratio method with estimates from one of the two correlation methods according to the respective variances of the estimates. Average standard errors of estimate for the final estimates ranged from 90.0 to 7.0 percent, with an average value of 26.5 percent. Average standard errors of estimate for the weighted estimates were, on average, 4.3 percent less than the best average standard errors of estima

Mechanism and kinetics of the loss of poorly soluble drugs from liposomal carriers studied by a novel flow field-flow fractionation-based drug release-/transfer-assay.

PubMed

Hinna, Askell Hvid; Hupfeld, Stefan; Kuntsche, Judith; Bauer-Brandl, Annette; Brandl, Martin

2016-06-28

Liposomes represent a versatile drug formulation approach e.g. for improving the water-solubility of poorly soluble drugs but also to achieve drug targeting and controlled release. For the latter applications it is essential that the drug remains associated with the liposomal carrier during transit in the vascular bed. A range of in vitro test methods has been suggested over the years for prediction of the release of drug from liposomal carriers. The majority of these fail to give a realistic prediction for poorly water-soluble drugs due to the intrinsic tendency of such compounds to remain associated with liposome bilayers even upon extensive dilution. Upon i.v. injection, in contrast, rapid drug loss often occurs due to drug transfer from the liposomal carriers to endogenous lipophilic sinks such as lipoproteins, plasma proteins or membranes of red blood cells and endothelial cells. Here we report on the application of a recently introduced in vitro predictive drug transfer assay based on incubation of the liposomal drug carrier with large multilamellar liposomes, the latter serving as a biomimetic model sink, using flow field-flow fractionation as a tool to separate the two types of liposomes. By quantifying the amount of drug remaining associated with the liposomal drug carrier as well as that transferred to the acceptor liposomes at distinct times of incubation, both the kinetics of drug transfer and release to the water phase could be established for the model drug p-THPP (5,10,15,20-tetrakis(4-hydroxyphenyl)21H,23H-porphine). p-THPP is structurally similar to temoporfin, a photosensitizer which is under clinical evaluation in a liposomal formulation. Mechanistic insights were gained by varying the donor-to-acceptor lipid mass ratio, size and lamellarity of the liposomes. Drug transfer kinetics from one liposome to another was found rate determining as compared to redistribution from the outermost to the inner concentric bilayers, such that the overall process could be adequately described by a single 1st order kinetic model. By varying the donor-to-acceptor lipid mass ratio in the range 1:1 to 1:10, a correlation was established between donor-to-acceptor-lipid mass ratio and transfer kinetics, which is regarded essential for scaling to physiological lipid mass ratios. By applying the assay to a series of structurally related model compounds of different bilayer affinity, transfer and release kinetics were established over the whole expected range of liposome bilayer associated drugs in terms of water solubility and lipophilicity. A very rapid transfer and considerable release from liposomes to the water phase was observed for the more water-soluble compounds Sudan II (clogP 5.45) and Sudan III (clogP 6.83). For the more lipophilic compounds, the rate of transfer from the donor liposomes followed the rank order Sudan IV (fastest)>Oil Red O>Sudan Black>p-THPP (slowest). For an equimolar donor-to-acceptor lipid mass ratio, half-lifes of transfer in the range of 12min (Sudan IV) up to 1.5h (p-THPP) were determined. In essence, the results presented here allow for both, mechanistic insights and predictions of drug loss from liposomal carriers upon exposure to biological sinks, which appear more realistic than the commonly employed in vitro release tests. Copyright © 2016 Elsevier B.V. All rights reserved.

A Bayesian Meta-Analysis on Prevalence of Hepatitis B Virus Infection among Chinese Volunteer Blood Donors

PubMed Central

Liu, Guang-ying; Zheng, Yang; Deng, Yan; Gao, Yan-yan; Wang, Lie

2013-01-01

Background Although transfusion-transmitted infection of hepatitis B virus (HBV) threatens the blood safety of China, the nationwide circumstance of HBV infection among blood donors is still unclear. Objectives To comprehensively estimate the prevalence of HBsAg positive and HBV occult infection (OBI) among Chinese volunteer blood donors through bayesian meta-analysis. Methods We performed an electronic search in Pub-Med, Web of Knowledge, Medline, Wanfang Data and CNKI, complemented by a hand search of relevant reference lists. Two authors independently extracted data from the eligible studies. Then two bayesian random-effect meta-analyses were performed, followed by bayesian meta-regressions. Results 5957412 and 571227 donors were identified in HBsAg group and OBI group, respectively. The pooled prevalence of HBsAg group and OBI group among donors is 1.085% (95% credible interval [CI] 0.859%∼1.398%) and 0.094% (95% CI 0.0578%∼0.1655%). For HBsAg group, subgroup analysis shows the more developed area has a lower prevalence than the less developed area; meta-regression indicates there is a significant decreasing trend in HBsAg positive prevalence with sampling year (beta = −0.1202, 95% −0.2081∼−0.0312). Conclusion Blood safety against HBV infection in China is suffering serious threats and the government should take effective measures to improve this situation. PMID:24236110

Early renal function recovery and long-term graft survival in kidney transplantation.

PubMed

Wan, Susan S; Cantarovich, Marcelo; Mucsi, Istvan; Baran, Dana; Paraskevas, Steven; Tchervenkov, Jean

2016-05-01

Following kidney transplantation (KTx), renal function improves gradually until a baseline eGFR is achieved. Whether or not a recipient achieves the best-predicted eGFR after KTx may have important implications for immediate patient management, as well as for long-term graft survival. The aim of this cohort study was to calculate the renal function recovery (RFR) based on recipient and donor eGFR and to evaluate the association between RFR and long-term death-censored graft failure (DCGF). We studied 790 KTx recipients between January 1990 and August 2014. The last donor SCr prior to organ procurement was used to estimate donor GFR. Recipient eGFR was calculated using the average of the best three SCr values observed during the first 3 months post-KTx. RFR was defined as the ratio of recipient eGFR to half the donor eGFR. 53% of recipients had an RFR ≥1. There were 127 death-censored graft failures (16%). Recipients with an RFR ≥1 had less DCGF compared with those with an RFR <1 (HR 0.56; 95% CI 0.37-0.85; P = 0.006). Transplant era, acute rejection, ECD and DGF were also significant determinants of graft failure. Early recovery of predicted eGFR based on donor eGFR is associated with less DCGF after KTx. © 2016 Steunstichting ESOT.

Application of phasor plot and autofluorescence correction for study of heterogeneous cell population

PubMed Central

Szmacinski, Henryk; Toshchakov, Vladimir; Lakowicz, Joseph R.

2014-01-01

Abstract. Protein-protein interactions in cells are often studied using fluorescence resonance energy transfer (FRET) phenomenon by fluorescence lifetime imaging microscopy (FLIM). Here, we demonstrate approaches to the quantitative analysis of FRET in cell population in a case complicated by a highly heterogeneous donor expression, multiexponential donor lifetime, large contribution of cell autofluorescence, and significant presence of unquenched donor molecules that do not interact with the acceptor due to low affinity of donor-acceptor binding. We applied a multifrequency phasor plot to visualize FRET FLIM data, developed a method for lifetime background correction, and performed a detailed time-resolved analysis using a biexponential model. These approaches were applied to study the interaction between the Toll Interleukin-1 receptor (TIR) domain of Toll-like receptor 4 (TLR4) and the decoy peptide 4BB. TLR4 was fused to Cerulean fluorescent protein (Cer) and 4BB peptide was labeled with Bodipy TMRX (BTX). Phasor displays for multifrequency FLIM data are presented. The analytical procedure for lifetime background correction is described and the effect of correction on FLIM data is demonstrated. The absolute FRET efficiency was determined based on the phasor plot display and multifrequency FLIM data analysis. The binding affinity between TLR4-Cer (donor) and decoy peptide 4BB-BTX (acceptor) was estimated in a heterogeneous HeLa cell population. PMID:24770662

Utilization of advanced-age donors in renal transplantation.

PubMed

Olaverri, J G; Mora Christian, J; Elorrieta, P; Esnaola, K; Rodríguez, P; Marrón, I; Uriarte, I; Landa, M J; Zarraga, S; Gainza, F J; Aranzabal, J; Zabala, J A; Pertusa, C

2011-11-01

The shortage of organ availability in recent years has made it necessary to use grafts from advanced-aged donors to maintain the rate of renal transplantation in our country. The objective of this study was to evaluate the graft function and patient survival using kidneys from deceased donors of over 65 year of age. From 2005 until 2010, we compared the outcomes of patients who received grafts from donors over 65 years old vs less than 65 years. We observed no significant difference in sex, time on dialysis, or cold ischemia time between the groups. As expected the recipient age was significantly different. For the analysis of survival, we used the Tablecloth-Haenzel test and the Kaplan-Meier survival estimator. Actuarial survivals at 3 years after transplantation showed 84.8% among patients transplanted with kidneys from donors over 65 years old versus 97.5% in the control group. The graft survival was 78.8% among expanded criteria versus 86.85% in the control group. When we analyzed graft survival using an "exitus-censured" analysis, we obtained graft survivals of 89.1% in the expanded criteria kidney group versus 88.6% among the controls. We concluded that the use of kidney from donors over 65 years of age allows us to increase the rate of renal transplantation to about 15 to 20 per million population, with good graft and patient survivals provided that the protocol for expanded criteria organs ensured proper macroscopic and microscopic evaluation of the organ for transplantation. Copyright © 2011. Published by Elsevier Inc.

The Not-so-massive Black Hole in the Microquasar GRS1915+105

NASA Astrophysics Data System (ADS)

Steeghs, D.; McClintock, J. E.; Parsons, S. G.; Reid, M. J.; Littlefair, S.; Dhillon, V. S.

2013-05-01

We present a new dynamical study of the black hole X-ray transient GRS1915+105 making use of near-infrared spectroscopy obtained with X-shooter at the Very Large Telescope. We detect a large number of donor star absorption features across a wide range of wavelengths spanning the H and K bands. Our 24 epochs covering a baseline of over 1 yr permit us to determine a new binary ephemeris including a refined orbital period of P = 33.85 ± 0.16 days. The donor star radial velocity curves deliver a significantly improved determination of the donor semi-amplitude which is both accurate (K 2 = 126 ± 1 km s-1) and robust against choice of donor star template and spectral features used. We furthermore constrain the donor star's rotational broadening to vsin i = 21 ± 4 km s-1, delivering a binary mass ratio of q = 0.042 ± 0.024. If we combine these new constraints with distance and inclination estimates derived from modeling the radio emission, a black hole mass of M BH = 10.1 ± 0.6 M ⊙ is inferred, paired with an evolved mass donor of M 2 = 0.47 ± 0.27 M ⊙. Our analysis suggests a more typical black hole mass for GRS1915+105 rather than the unusually high values derived in the pioneering dynamical study by Greiner et al. Our data demonstrate that high-resolution infrared spectroscopy of obscured accreting binaries can deliver dynamical mass determinations with a precision on par with optical studies.

Seroprevalence of Asymptomatic Dengue Virus Infection and Its Antibodies Among Healthy/Eligible Saudi Blood Donors: Findings From Holy Makkah City.

PubMed

Ashshi, Ahmed M; Alghamdi, Saad; El-Shemi, Adel G; Almdani, Sabir; Refaat, Bassem; Mohamed, Amr M; Ghazi, Hani O; Azhar, Esam I; Al-Allaf, Faisal A

2017-01-01

Threat to blood transfusion-transmitted dengue virus (DENV) and its antibodies has recently emerged worldwide. Dengue fever is an endemic disease in Saudi Arabia, particularly in its Western region. The aim of this study was to estimate the seroprevalence of asymptomatic DENV infection and its antibodies among eligible Saudi blood donors. Serum samples from 910 healthy/eligible adult male Saudi blood donors, who reside in Holy Makkah City of Saudi Arabia, were collected between March 2015 and August 2016 and screened for the detection of DENV nonstructural protein 1 (NS1) antigen and anti-DENV IgM and IgG antibodies using commercial enzyme-linked immunosorbent assay kits (Panbio, Brisbane, QLD, Australia). Among the tested donors, 48 (5.3%) were seropositive for DENV-NS1 antigen, whereas 50 (5.5%) and 354 (38.9%) were seropositive for anti-DENV IgM and IgG antibodies, respectively. Seropositivity for DENV-NS1 antigen and/or anti-DENV IgM antibody among the tested donors reflects their ongoing asymptomatic viremic infectious stage with DENV during their donation time, whereas high prevalence of anti-DENV IgG seropositivity reflects the high endemicity of dengue disease in this region of Saudi Arabia. These results show high prevalence of asymptomatic DENV infection and its antibodies among Saudi blood donors, raising the importance of establishing blood screening for dengue disease at different blood donation services and units in Saudi Arabia to improve the guarantee of blood transfusions and to control DENV dissemination.

The Kidney Donor Profile Index (KDPI) of marginal donors allocated by standardized pretransplant donor biopsy assessment: distribution and association with graft outcomes.

PubMed

Gandolfini, I; Buzio, C; Zanelli, P; Palmisano, A; Cremaschi, E; Vaglio, A; Piotti, G; Melfa, L; La Manna, G; Feliciangeli, G; Cappuccilli, M; Scolari, M P; Capelli, I; Panicali, L; Baraldi, O; Stefoni, S; Buscaroli, A; Ridolfi, L; D'Errico, A; Cappelli, G; Bonucchi, D; Rubbiani, E; Albertazzi, A; Mehrotra, A; Cravedi, P; Maggiore, U

2014-11-01

Pretransplant donor biopsy (PTDB)-based marginal donor allocation systems to single or dual renal transplantation could increase the use of organs with Kidney Donor Profile Index (KDPI) in the highest range (e.g. >80 or >90), whose discard rate approximates 50% in the United States. To test this hypothesis, we retrospectively calculated the KDPI and analyzed the outcomes of 442 marginal kidney transplants (340 single transplants: 278 with a PTDB Remuzzi score<4 [median KDPI: 87; interquartile range (IQR): 78-94] and 62 with a score=4 [median KDPI: 87; IQR: 76-93]; 102 dual transplants [median KDPI: 93; IQR: 86-96]) and 248 single standard transplant controls (median KDPI: 36; IQR: 18-51). PTDB-based allocation of marginal grafts led to a limited discard rate of 15% for kidneys with KDPI of 80-90 and of 37% for kidneys with a KDPI of 91-100. Although 1-year estimated GFRs were significantly lower in recipients of marginal kidneys (-9.3, -17.9 and -18.8 mL/min, for dual transplants, single kidneys with PTDB score<4 and =4, respectively; p<0.001), graft survival (median follow-up 3.3 years) was similar between marginal and standard kidney transplants (hazard ratio: 1.20 [95% confidence interval: 0.80-1.79; p=0.38]). In conclusion, PTDB-based allocation allows the safe transplantation of kidneys with KDPI in the highest range that may otherwise be discarded. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.

Estimates of Flow Duration, Mean Flow, and Peak-Discharge Frequency Values for Kansas Stream Locations

USGS Publications Warehouse

Perry, Charles A.; Wolock, David M.; Artman, Joshua C.

2004-01-01

Streamflow statistics of flow duration and peak-discharge frequency were estimated for 4,771 individual locations on streams listed on the 1999 Kansas Surface Water Register. These statistics included the flow-duration values of 90, 75, 50, 25, and 10 percent, as well as the mean flow value. Peak-discharge frequency values were estimated for the 2-, 5-, 10-, 25-, 50-, and 100-year floods. Least-squares multiple regression techniques were used, along with Tobit analyses, to develop equations for estimating flow-duration values of 90, 75, 50, 25, and 10 percent and the mean flow for uncontrolled flow stream locations. The contributing-drainage areas of 149 U.S. Geological Survey streamflow-gaging stations in Kansas and parts of surrounding States that had flow uncontrolled by Federal reservoirs and used in the regression analyses ranged from 2.06 to 12,004 square miles. Logarithmic transformations of climatic and basin data were performed to yield the best linear relation for developing equations to compute flow durations and mean flow. In the regression analyses, the significant climatic and basin characteristics, in order of importance, were contributing-drainage area, mean annual precipitation, mean basin permeability, and mean basin slope. The analyses yielded a model standard error of prediction range of 0.43 logarithmic units for the 90-percent duration analysis to 0.15 logarithmic units for the 10-percent duration analysis. The model standard error of prediction was 0.14 logarithmic units for the mean flow. Regression equations used to estimate peak-discharge frequency values were obtained from a previous report, and estimates for the 2-, 5-, 10-, 25-, 50-, and 100-year floods were determined for this report. The regression equations and an interpolation procedure were used to compute flow durations, mean flow, and estimates of peak-discharge frequency for locations along uncontrolled flow streams on the 1999 Kansas Surface Water Register. Flow durations, mean flow, and peak-discharge frequency values determined at available gaging stations were used to interpolate the regression-estimated flows for the stream locations where available. Streamflow statistics for locations that had uncontrolled flow were interpolated using data from gaging stations weighted according to the drainage area and the bias between the regression-estimated and gaged flow information. On controlled reaches of Kansas streams, the streamflow statistics were interpolated between gaging stations using only gaged data weighted by drainage area.

In utero transplantation of human bone marrow-derived multipotent mesenchymal stem cells in mice.

PubMed

Chou, Shiu-Huey; Kuo, Tom K; Liu, Ming; Lee, Oscar K

2006-03-01

Mesenchymal stem cells (MSCs) are multipotent cells that can be isolated from human bone marrow and possess the potential to differentiate into progenies of embryonic mesoderm. However, current evidence is based predominantly on in vitro experiments. We used a murine model of in utero transplantation (IUT) to study the engraftment capabilities of human MSCs. MSCs were obtained from bone marrow by negative immunoselection and limiting dilution, and were characterized by flow cytometry and by in vitro differentiation into osteoblasts, chondrocytes, and adipocytes. MSCs were transplanted into fetal mice at a gestational age of 14 days. Engraftment of human MSCs was determined by flow cytometry, polymerase chain reaction, and fluorescence in situ hybridization (FISH). MSCs engrafted into tissues originating from all three germ layers and persisted for up to 4 months or more after delivery, as evidenced by the expression of the human-specific beta-2 microglobulin gene and by FISH for donor-derived cells. Donor-derived CD45+ cells were detectable in the peripheral blood of recipients, suggesting the participation of MSCs in hematopoiesis at the fetal stage. This model can further serve to evaluate possible applications of MSCs. Copyright 2006 Orthopaedic Research Society.

Optical Coherence Tomography in Kidney Transplantation

NASA Astrophysics Data System (ADS)

Andrews, Peter M.; Wierwille, Jeremiah; Chen, Yu

End-stage renal disease (ESRD) is associated with both high mortality rates and an enormous economic burden [1]. The preferred treatment option for ESRD that can extend patients' lives and improve their quality of life is kidney transplantation. However, organ shortages continue to pose a major problem in kidney transplantation. Most kidneys for transplantation come from heart-beating cadavers. Although non-heart-beating cadavers represent a potentially large pool of donor kidneys, these kidneys are not often used due to the unknown extent of damage to the renal tubules (i.e., acute tubular necrosis or "ATN") induced by ischemia (i.e., lack of blood flow). Also, ischemic insult suffered by kidneys awaiting transplantation frequently causes ATN that leads to varying degrees of delayed graft function (DGF) after transplantation. Finally, ATN represents a significant risk for eventual graft and patient survival [2, 3] and can be difficult to discern from rejection. In present clinical practice, there is no reliable real-time test to determine the viability of donor kidneys and whether or not donor kidneys might exhibit ATN. Therefore, there is a critical need for an objective and reliable real-time test to predict ATN to use these organs safely and utilize the donor pool optimally. In this review, we provided preliminary data indicating that OCT can be used to predict the post-transplant function of kidneys used in transplantation.

Microfluidic passive permeability assay using nanoliter droplet interface lipid bilayers.

PubMed

Nisisako, Takasi; Portonovo, Shiva A; Schmidt, Jacob J

2013-11-21

Membrane permeability assays play an important role in assessing drug transport activities across biological membranes. However, in conventional parallel artificial membrane permeability assays (PAMPA), the membrane model used is dissimilar to biological membranes physically and chemically. Here, we describe a microfluidic passive permeability assay using droplet interface bilayers (DIBs). In a microfluidic network, nanoliter-sized donor and acceptor aqueous droplets are alternately formed in cross-flowing oil containing phospholipids. Subsequently, selective removal of oil through hydrophobic pseudo-porous sidewalls induces the contact of the lipid monolayers, creating arrayed planar DIBs between the donor and acceptor droplets. Permeation of fluorescein from the donor to the acceptor droplets was fluorometrically measured. From the measured data and a simple diffusion model we calculated the effective permeabilities of 5.1 × 10(-6) cm s(-1), 60.0 × 10(-6) cm s(-1), and 87.6 × 10(-6) cm s(-1) with donor droplets at pH values of 7.5, 6.4 and 5.4, respectively. The intrinsic permeabilities of specific monoanionic and neutral fluorescein species were obtained similarly. We also measured the permeation of caffeine in 10 min using UV microspectroscopy, obtaining a permeability of 20.8 × 10(-6) cm s(-1). With the small solution volumes, short measurement time, and ability to measure a wide range of compounds, this device has considerable potential as a platform for high-throughput drug permeability assays.

Living Bone Allotransplants Survive by Surgical Angiogenesis Alone: Development of a Novel Method of Composite Tissue Allotransplantation

PubMed Central

Larsen, Mikko; Pelzer, Michael; Friedrich, Patricia F.; Wood, Christina M.; Bishop, Allen T.

2011-01-01

Background: Segmental bone defects pose reconstructive challenges. Composite tissue allotransplantation offers a potential solution but requires long-term immunosuppression with attendant health risks. This study demonstrates a novel method of composite-tissue allotransplantation, permitting long-term drug-free survival, with use of therapeutic angiogenesis of autogenous vessels to maintain circulation. Methods: Ninety-three rats underwent femoral allotransplantation, isotransplantation, or allografting. Group-1 femora were transplanted across a major histocompatibility complex barrier, with microsurgical pedicle anastomoses. The contralateral saphenous artery and vein (termed the AV bundle) of the recipient animal were implanted within the medullary canal to allow development of an autogenous circulation. In Group 2, allotransplantation was also performed, but with AV bundle ligation. Group 3 bones were frozen allografts rather than composite-tissue allotransplantation femora, and Group 4 bones were isotransplants. Paired comparison allowed evaluation of AV bundle effect, bone allogenicity (isogeneic or allogeneic), and initial circulation and viability (allotransplant versus allograft). Two weeks of immunosuppression therapy maintained blood flow initially, during development of a neoangiogenic autogenous blood supply from the AV bundle in patent groups. At eighteen weeks, skin grafts from donor, recipient, and third-party rats were tested for immunocompetence and donor-specific tolerance. At twenty-one weeks, bone circulation was quantified and new bone formation was measured. Results: Final circulatory status depended on both the initial viability of the graft and the successful development of neoangiogenic circulation. Median cortical blood flow was highest in Group 1 (4.6 mL/min/100 g), intermediate in Group 4 isotransplants (0.4 mL/min/100 g), and absent in others. Capillary proliferation and new bone formation were generally highest in allotransplants (15.0%, 6.4 μm3/μm2/yr) and isotransplants with patent AV bundles (16.6%, 50.3 μm3/μm2/yr) and less in allotransplants with ligated AV bundles (4.4%, 0.0 μm3/μm2/yr) or allografts (8.1%, 24.1 μm3/μm2/yr). Donor and third-party-type skin grafts were rejected, indicating immunocompetence without donor-specific tolerance. Conclusions: In the rat model, microvascular allogeneic bone transplantation in combination with short-term immunosuppression and AV bundle implantation creates an autogenous neoangiogenic circulation, permitting long-term allotransplant survival with measurable blood flow. Clinical Relevance: These methods may allow future composite-tissue allotransplantation of bone without the appreciable health risks that are associated with long-term immunosuppression or immune tolerance induction. PMID:21266640

Pollen-mediated gene flow in flax (Linum usitatissimum L.): can genetically engineered and organic flax coexist?

PubMed Central

Jhala, A J; Bhatt, H; Topinka, K; Hall, L M

2011-01-01

Coexistence allows growers and consumers the choice of producing or purchasing conventional or organic crops with known standards for adventitious presence of genetically engineered (GE) seed. Flax (Linum usitatissimum L.) is multipurpose oilseed crop in which product diversity and utility could be enhanced for industrial, nutraceutical and pharmaceutical markets through genetic engineering. If GE flax were released commercially, pollen-mediated gene flow will determine in part whether GE flax could coexist without compromising other markets. As a part of pre-commercialization risk assessment, we quantified pollen-mediated gene flow between two cultivars of flax. Field experiments were conducted at four locations during 2006 and 2007 in western Canada using a concentric donor (20 × 20 m) receptor (120 × 120 m) design. Gene flow was detected through the xenia effect of dominant alleles of high α-linolenic acid (ALA; 18:3cisΔ9,12,15) to the low ALA trait. Seeds were harvested from the pollen recipient plots up to a distance of 50 m in eight directions from the pollen donor. High ALA seeds were identified using a thiobarbituric acid test and served as a marker for gene flow. Binomial distribution and power analysis were used to predict the minimum number of seeds statistically required to detect the frequency of gene flow at specific α (confidence interval) and power (1−β) values. As a result of the low frequency of gene flow, approximately 4 million seeds were screened to derive accurate quantification. Frequency of gene flow was highest near the source: averaging 0.0185 at 0.1 m but declined rapidly with distance, 0.0013 and 0.00003 at 3 and 35 m, respectively. Gene flow was reduced to 50% (O50) and 90% (O90) between 0.85 to 2.64 m, and 5.68 to 17.56 m, respectively. No gene flow was detected at any site or year >35 m distance from the pollen source, suggesting that frequency of gene flow was ⩽0.00003 (P=0.95). Although it is not possible to eliminate all adventitious presence caused by pollen-mediated gene flow, through harvest blending and the use of buffer zones between GE and conventional flax fields, it could be minimized. Managing other sources of adventitious presence including seed mixing and volunteer populations may be more problematic. PMID:20551976

Robust and efficient overset grid assembly for partitioned unstructured meshes

NASA Astrophysics Data System (ADS)

Roget, Beatrice; Sitaraman, Jayanarayanan

2014-03-01

This paper presents a method to perform efficient and automated Overset Grid Assembly (OGA) on a system of overlapping unstructured meshes in a parallel computing environment where all meshes are partitioned into multiple mesh-blocks and processed on multiple cores. The main task of the overset grid assembler is to identify, in parallel, among all points in the overlapping mesh system, at which points the flow solution should be computed (field points), interpolated (receptor points), or ignored (hole points). Point containment search or donor search, an algorithm to efficiently determine the cell that contains a given point, is the core procedure necessary for accomplishing this task. Donor search is particularly challenging for partitioned unstructured meshes because of the complex irregular boundaries that are often created during partitioning.

Electrical Manipulation of Donor Spin Qubits in Silicon and Germanium

NASA Astrophysics Data System (ADS)

Sigillito, Anthony James

Many proposals for quantum information devices rely on electronic or nuclear spins in semiconductors because of their long coherence times and compatibility with industrial fabrication processes. One of the most notable qubits is the electron spin bound to phosphorus donors in silicon, which offers coherence times exceeding seconds at low temperatures. These donors are naturally isolated from their environments to the extent that silicon has been coined a "semiconductor vacuum". While this makes for ultra-coherent qubits, it is difficult to couple two remote donors so quantum information proposals rely on high density arrays of qubits. Here, single qubit addressability becomes an issue. Ideally one would address individual qubits using electric fields which can be easily confined. Typically these schemes rely on tuning a donor spin qubit onto and off of resonance with a magnetic driving field. In this thesis, we measure the electrical tunability of phosphorus donors in silicon and use the extracted parameters to estimate the effects of electric-field noise on qubit coherence times. Our measurements show that donor ionization may set in before electron spins can be sufficiently tuned. We therefore explore two alternative options for qubit addressability. First, we demonstrate that nuclear spin qubits can be directly driven using electric fields instead of magnetic fields and show that this approach offers several advantages over magnetically driven spin resonance. In particular, spin transitions can occur at half the spin resonance frequency and double quantum transitions (magnetic-dipole forbidden) can occur. In a second approach to realizing tunable qubits in semiconductors, we explore the option of replacing silicon with germanium. We first measure the coherence and relaxation times for shallow donor spin qubits in natural and isotopically enriched germanium. We find that in isotopically enriched material, coherence times can exceed 1 ms and are limited by a single-phonon T1 process. At lower frequencies or lower temperatures the qubit coherence times should substantially increase. Finally, we measure the electric field tunability of donors in germanium and find a four order-of-magnitude enhancement in the spin-orbit Stark shift and confirm that the donors should be tunable by at least 4 times the electron spin ensemble linewidth (in isotopically enriched material). Germanium should therefore also be more sensitive to electrically driven nuclear magnetic resonance. Based on these results germanium is a promising alternative to silicon for spin qubits.

Resonance energy transfer between the active sites of creatine kinase from rabbit brain.

PubMed

Grossman, S H

1990-09-03

Resonance energy transfer was measured between the active site domains of the brain isozyme of creatine kinase (CK-BB). The reactive thiol near the active sites, one on each subunit of the dimeric protein, was derivatized using 5-[2-[iodoacetyl)amino)ethyl]aminonaphthalene-1-sulfonic acid (AED), 2-[4'-iodoacetamidoanilino]naphthalene-6-sulfonic acid (AANS) and 5-iodoacetamidofluorescein (AF). Suitable donor/acceptor protein conjugated hybrids were prepared by controlled kinetics producing CK-BB-AED/AF and CK-BB-AANS/AF. Transfer efficiencies, measured from the quenching of the donor lifetime and steady-state sensitized acceptor emission, ranged from 0.10 to 0.17. From determination of the donor/acceptor overlap integrals, donor quantum yields and attempts to delimit the orientation factor using steady-state and phase-resolved anisotropy measurements, it was found that a suitable estimate of the range between the active sites was between 45 and 57 A. This range is similar to that reported previously for the muscle isozyme of creatine kinase (Grossman, S.H. (1989) Biochemistry 28, 4894-4902) but is a significantly greater distance than detected for the hybrid, myocardial specific isozyme (Grossman, S.H. (1983) Biochemistry 22, 5369-5375).

Afghanistan [Education Sector Fact Sheet

ERIC Educational Resources Information Center

US Agency for International Development, 2015

2015-01-01

Three decades of conflict devastated Afghanistan's education systems and institutions. In 2002, an estimated 900,000 boys attended school, while women and girls were almost completely excluded from educational opportunities. Since then, the Afghan government, USAID, and international donors have worked closely to rebuild Afghanistan's education…

Local scattering property scales flow speed estimation in laser speckle contrast imaging

NASA Astrophysics Data System (ADS)

Miao, Peng; Chao, Zhen; Feng, Shihan; Yu, Hang; Ji, Yuanyuan; Li, Nan; Thakor, Nitish V.

2015-07-01

Laser speckle contrast imaging (LSCI) has been widely used in in vivo blood flow imaging. However, the effect of local scattering property (scattering coefficient µ s ) on blood flow speed estimation has not been well investigated. In this study, such an effect was quantified and involved in relation between speckle autocorrelation time τ c and flow speed v based on simulation flow experiments. For in vivo blood flow imaging, an improved estimation strategy was developed to eliminate the estimation bias due to the inhomogeneous distribution of the scattering property. Compared to traditional LSCI, a new estimation method significantly suppressed the imaging noise and improves the imaging contrast of vasculatures. Furthermore, the new method successfully captured the blood flow changes and vascular constriction patterns in rats’ cerebral cortex from normothermia to mild and moderate hypothermia.

Activation of NK Cells in Mixed Cultures of Wharton's Jelly Mesenchymal Stromal Cells and Peripheral Blood Lymphocytes.

PubMed

Svirshchevskaya, E V; Poltavtsev, A M; Os'mak, G Zh; Poltavtseva, R A

2018-01-01

Mesenchymal stromal cells possess immunosuppressive properties that might be used for the therapy of inflammatory diseases of various geneses. The effects of mesenchymal stromal cells depend on their lifetime in the recipient tissues. During heterologous transplantation, mesenchymal stromal cells are eliminated by NK cells. We studied NK cell formation in mixed cultures of Wharton's jelly mesenchymal stromal cells and peripheral blood lymphocytes from an autologous donor. Lymphocytes were activated by a mitogen or IL-2. The lifetime of mesenchymal stromal cells was estimated by MTT test. Cytotoxic activity and phenotype of NK cells were evaluated by flow cytometry. It was found that activation of NK cells depended on IL-2 and was registered on day 2 of incubation with IL-2. In cultures with mitogen-activated lymphocytes, cytotoxicity was observed after 5-6 days. Cytotoxicity of NK correlated with significant decrease in CD16+ and increase in CD56+ NK and with reduction of mesenchymal stromal cell viability. Thus, the main mechanism of elimination of mesenchymal stromal cells is cytotoxicity of NK cells that depended on IL-2 production.

Excellent outcome of matched unrelated donor transplantation in paediatric aplastic anaemia following failure with immunosuppressive therapy: a United Kingdom multicentre retrospective experience.

PubMed

Samarasinghe, Sujith; Steward, Colin; Hiwarkar, Prashant; Saif, Muhammad Ameer; Hough, Rachael; Webb, David; Norton, Alice; Lawson, Sarah; Qureshi, Amrana; Connor, Philip; Carey, Peter; Skinner, Rod; Vora, Ajay; Pelidis, Maria; Gibson, Brenda; Stewart, Graham; Keogh, Steve; Goulden, Nick; Bonney, Denise; Stubbs, Mathew; Amrolia, Persis; Rao, Kanchan; Meyer, Stefan; Wynn, Rob; Veys, Paul

2012-05-01

We retrospectively analysed the outcome of consecutive children with idiopathic severe aplastic anaemia in the United Kingdom who received immunosuppressive therapy (IST) or matched unrelated donor (MUD) haematopoietic stem cell transplantation (HSCT). The 6-month cumulative response rate following rabbit antithymocyte globulin (ATG)/ciclosporin (IST) was 32·5% (95% CI 19·3-46·6) (n = 43). The 5-year estimated failure-free survival (FFS) following IST was 13·3% (95% confidence interval [CI] 4·0-27·8). In contrast, in 44 successive children who received a 10-antigen (HLA-A, -B, -C, -DRB1, -DQB1) MUD HSCT there was an excellent estimated 5-year FFS of 95·01% (95% CI 81·38-98·74). Forty of these children had failed IST previously. HSCT conditioning was a fludarabine, cyclophosphamide and alemtuzumab (FCC) regimen and did not include radiotherapy. There were no cases of graft failure. Median donor chimerism was 100% (range 88-100%). A conditioning regimen, such as FCC that avoids total body irradiation is ideally suited in children. Our data suggest that MUD HSCT following IST failure offers an excellent outcome and furthermore, if a suitable MUD can be found quickly, MUD HSCT may be a reasonable alternative to IST. © 2012 Blackwell Publishing Ltd.

Significant Association between Sulfate-Reducing Bacteria and Uranium-Reducing Microbial Communities as Revealed by a Combined Massively Parallel Sequencing-Indicator Species Approach▿ †

PubMed Central

Cardenas, Erick; Wu, Wei-Min; Leigh, Mary Beth; Carley, Jack; Carroll, Sue; Gentry, Terry; Luo, Jian; Watson, David; Gu, Baohua; Ginder-Vogel, Matthew; Kitanidis, Peter K.; Jardine, Philip M.; Zhou, Jizhong; Criddle, Craig S.; Marsh, Terence L.; Tiedje, James M.

2010-01-01

Massively parallel sequencing has provided a more affordable and high-throughput method to study microbial communities, although it has mostly been used in an exploratory fashion. We combined pyrosequencing with a strict indicator species statistical analysis to test if bacteria specifically responded to ethanol injection that successfully promoted dissimilatory uranium(VI) reduction in the subsurface of a uranium contamination plume at the Oak Ridge Field Research Center in Tennessee. Remediation was achieved with a hydraulic flow control consisting of an inner loop, where ethanol was injected, and an outer loop for flow-field protection. This strategy reduced uranium concentrations in groundwater to levels below 0.126 μM and created geochemical gradients in electron donors from the inner-loop injection well toward the outer loop and downgradient flow path. Our analysis with 15 sediment samples from the entire test area found significant indicator species that showed a high degree of adaptation to the three different hydrochemical-created conditions. Castellaniella and Rhodanobacter characterized areas with low pH, heavy metals, and low bioactivity, while sulfate-, Fe(III)-, and U(VI)-reducing bacteria (Desulfovibrio, Anaeromyxobacter, and Desulfosporosinus) were indicators of areas where U(VI) reduction occurred. The abundance of these bacteria, as well as the Fe(III) and U(VI) reducer Geobacter, correlated with the hydraulic connectivity to the substrate injection site, suggesting that the selected populations were a direct response to electron donor addition by the groundwater flow path. A false-discovery-rate approach was implemented to discard false-positive results by chance, given the large amount of data compared. PMID:20729318

Significant association between sulfate-reducing bacteria and uranium-reducing microbial communities as revealed by a combined massively parallel sequencing-indicator species approach.

PubMed

Cardenas, Erick; Wu, Wei-Min; Leigh, Mary Beth; Carley, Jack; Carroll, Sue; Gentry, Terry; Luo, Jian; Watson, David; Gu, Baohua; Ginder-Vogel, Matthew; Kitanidis, Peter K; Jardine, Philip M; Zhou, Jizhong; Criddle, Craig S; Marsh, Terence L; Tiedje, James M

2010-10-01

Massively parallel sequencing has provided a more affordable and high-throughput method to study microbial communities, although it has mostly been used in an exploratory fashion. We combined pyrosequencing with a strict indicator species statistical analysis to test if bacteria specifically responded to ethanol injection that successfully promoted dissimilatory uranium(VI) reduction in the subsurface of a uranium contamination plume at the Oak Ridge Field Research Center in Tennessee. Remediation was achieved with a hydraulic flow control consisting of an inner loop, where ethanol was injected, and an outer loop for flow-field protection. This strategy reduced uranium concentrations in groundwater to levels below 0.126 μM and created geochemical gradients in electron donors from the inner-loop injection well toward the outer loop and downgradient flow path. Our analysis with 15 sediment samples from the entire test area found significant indicator species that showed a high degree of adaptation to the three different hydrochemical-created conditions. Castellaniella and Rhodanobacter characterized areas with low pH, heavy metals, and low bioactivity, while sulfate-, Fe(III)-, and U(VI)-reducing bacteria (Desulfovibrio, Anaeromyxobacter, and Desulfosporosinus) were indicators of areas where U(VI) reduction occurred. The abundance of these bacteria, as well as the Fe(III) and U(VI) reducer Geobacter, correlated with the hydraulic connectivity to the substrate injection site, suggesting that the selected populations were a direct response to electron donor addition by the groundwater flow path. A false-discovery-rate approach was implemented to discard false-positive results by chance, given the large amount of data compared.

In vitro and in vivo assessment of cellular permeability and pharmacodynamics of S-nitrosylated Captopril, a nitric oxide donor

PubMed Central

Jia, Lee; Wong, Hong

2001-01-01

The present studies were aimed at testing the hypothesis that S-nitrosylated captopril (CapNO), a novel crystalline nitric oxide (NO) donor, readily permeates both in vitro and in vivo endothelial monolayers, resulting in its pharmacodynamic effects. CapNO and Captopril (Cap) were added to apical side of endothelial monolayers formed on microporous membranes, and the permeated drugs were collected from basolateral side and detected by a HPLC method. The permeability coefficient (Papp; cm sec−1) of CapNO across the endothelial monolayers was 6.0×10−5, higher than that of Cap (3.13×10−5), indicating the enhancement effect of the attached NO group in CapNO on cellular permeability. The Papp of CapNO and Cap across Caco-2 cells were 3.15×10−5 and 1.53×10−5, respectively. The low Papp of CapNO to Caco-2 cells may be attributed to the high membrane resistance of Caco-2 cells. A bolus injection of CapNO to epicardial coronary artery of chronically-instrumented awake dogs caused significant increases in coronary blood flow and coronary diameters dose-dependently without significant changes in aortic pressure. In contrast, the equimolar doses of Cap did not produce haemodynamic responses. Intravenous CapNO caused an instant increase in the regional cerebral blood flow determined by H2-clearance, whereas the equimolar doses of Cap did not enhance the cerebral blood flow. These results conclude that the NO group, an active component of CapNO, enhances both in vitro and in vivo endothelial permeability to the entire compound, resulting in instant increases in blood flow and vascular diameters. In contrast, the equimolar Cap does not have the instant vascular effects. PMID:11739246

In vitro and in vivo assessment of cellular permeability and pharmacodynamics of S-nitrosylated captopril, a nitric oxide donor.

PubMed

Jia, L; Wong, H

2001-12-01

1. The present studies were aimed at testing the hypothesis that S-nitrosylated captopril (CapNO), a novel crystalline nitric oxide (NO) donor, readily permeates both in vitro and in vivo endothelial monolayers, resulting in its pharmacodynamic effects. 2. CapNO and Captopril (Cap) were added to apical side of endothelial monolayers formed on microporous membranes, and the permeated drugs were collected from basolateral side and detected by a HPLC method. The permeability coefficient (P(app); cm sec(-1)) of CapNO across the endothelial monolayers was 6.0 x 10(-5), higher than that of Cap (3.13 x 10(-5)), indicating the enhancement effect of the attached NO group in CapNO on cellular permeability. The P(app) of CapNO and Cap across Caco-2 cells were 3.15 x 10(-5) and 1.53 x 10(-5), respectively. The low P(app) of CapNO to Caco-2 cells may be attributed to the high membrane resistance of Caco-2 cells. 3. A bolus injection of CapNO to epicardial coronary artery of chronically-instrumented awake dogs caused significant increases in coronary blood flow and coronary diameters dose-dependently without significant changes in aortic pressure. In contrast, the equimolar doses of Cap did not produce haemodynamic responses. 4. Intravenous CapNO caused an instant increase in the regional cerebral blood flow determined by H(2)-clearance, whereas the equimolar doses of Cap did not enhance the cerebral blood flow. 5. These results conclude that the NO group, an active component of CapNO, enhances both in vitro and in vivo endothelial permeability to the entire compound, resulting in instant increases in blood flow and vascular diameters. In contrast, the equimolar Cap does not have the instant vascular effects.

Pulmonary immune responses to Mycobacterium tuberculosis in exposed individuals

PubMed Central

Ernst, Martin; Lange, Christoph; Stenger, Steffen; Kaufmann, Stefan H. E.; Reiling, Norbert; Schaberg, Tom; van der Merwe, Lize; Maertzdorf, Jeroen

2017-01-01

Background Blood based Interferon-(IFN)-γ release assays (IGRAs) have a poor predictive value for the development of tuberculosis. This study aimed to investigate the correlation between IGRAs and pulmonary immune responses in tuberculosis contacts in Germany. Methods IGRAs were performed on bronchoalveolar lavage (BAL) cells and peripheral blood from close healthy contacts of patients with culturally confirmed tuberculosis. Cellular BAL composition was determined by flow cytometry. BAL cells were co-cultured with three strains of Mycobacterium tuberculosis (Mtb) and Mtb derived antigens including Purified Protein Derivative (PPD), 6 kD Early Secretory Antigenic Target (ESAT-6) and 10 kD Culture Filtrate Protein (CFP-10). Levels of 29 cytokines and chemokines were analyzed in the supernatants by multiplex assay. Associations and effects were examined using linear mixed-effects models. Results There were wide variations of inter-individual cytokine levels in BAL cell culture supernatants. Mycobacterial infection and stimulation with PPD showed a clear induction of several macrophage and lymphocyte associated cytokines, reflecting activation of these cell types. No robust correlation between cytokine patterns and blood IGRA status of the donor was observed, except for slightly higher Interleukin-2 (IL-2) responses in BAL cells from IGRA-positive donors upon mycobacterial infection compared to cells from IGRA-negative donors. Stronger correlations were observed when cytokine patterns were stratified according to BAL IGRA status. BAL cells from donors with BAL IGRA-positive responses produced significantly more IFN-γ and IL-2 upon PPD stimulation and mycobacterial infection than cells from BAL IGRA-negative individuals. Correlations between BAL composition and basal cytokine release from unstimulated cells were suggestive of pre-activated lymphocytes but impaired macrophage activity in BAL IGRA-positive donors, in contrast to BAL IGRA-negative donors. Conclusions In vitro BAL cell cytokine responses to M. tuberculosis antigens or infection do not reflect blood IGRA status but do correlate with stronger cellular responses in BAL IGRA-positive donors. The cytokine patterns observed suggest a pre-activated state of lymphocytes and suppressed macrophage responsiveness in BAL cells from BAL IGRA-positive individuals. PMID:29125874

Enhanced uptake of multiple sclerosis-derived myelin by THP-1 macrophages and primary human microglia

PubMed Central

2014-01-01

Background The pathological hallmark of multiple sclerosis (MS) is myelin phagocytosis. It remains unclear why microglia and macrophages demyelinate axons in MS, but previously found or yet-unknown changes in the myelin of MS patients could contribute to this process. We therefore studied whether myelin from normal-appearing white matter (NAWM) of MS donors is phagocytosed more efficiently than myelin from control donors. Methods Myelin was isolated from 11 MS and 12 control brain donors and labeled with the pH-sensitive fluorescent dye pHrodo to quantify uptake in lysosomes. Phagocytosis by differentiated THP-1 macrophages and by primary human microglia was quantified with flow cytometry. Whereas myelin uptake by THP-1 macrophages reached a plateau after approximately 24 hours, uptake by primary human microglia showed an almost linear increase over a 72–hour period. Data were statistically analyzed with the Mann–Whitney U test. Results MS-derived myelin was phagocytosed more efficiently by THP-1 macrophages after 6-hour incubation (P = 0.001 for the percentage of myelin-phagocytosing cells and P = 0.0005 for total myelin uptake) and after 24-hour incubation (P = 0.0006 and P = 0.0001, respectively), and by microglia after 24-hour incubation (P = 0.0106 for total myelin uptake). This enhanced uptake was not due to differences in the oxidation status of the myelin. Interestingly, myelin phagocytosis correlated negatively with the age of myelin donors, whereas the age of microglia donors showed a positive trend with myelin phagocytosis. Conclusions Myelin isolated from normal-appearing white matter of MS donors was phagocytosed more efficiently than was myelin isolated from control brain donors by both THP-1 macrophages and primary human microglia. These data indicate that changes in MS myelin might precede phagocyte activation and subsequent demyelination in MS. Identifying these myelin changes responsible for enhancing phagocytic ability could be an interesting therapeutic target to prevent or inhibit formation or expansion of MS lesions. Moreover, during aging, microglia enhance their phagocytic capacity for myelin phagocytosis, but myelin reduces its susceptibility for uptake. PMID:24684721

Effects of Aging on the Proliferation and Differentiation Capacity of Human Periodontal Ligament Stem Cells.

PubMed

Du, Tingting; Liu, Na; Gu, Bin; Li, Ying; Yuan, Yifang; Zhang, Wei; Zhang, Tong

2017-06-10

Objective The aim of this study is to investigate the proliferation, differentiation and apoptosis of periodontal ligament stem cells (PDLSC) derived from different aged donors, and to evaluate the effects of aging on the biological characteristics of PDLSC.Methods Periodontal ligament tissues were obtained from 24 surgically extracted human premolars during orthodontics therapy. The specimens were divided into three groups according to the donor's age. Group A: 18-20 years, group B: 30-35 years, group C: 45-50 years. PDLSC were isolated and cultured using a tissue-block-based enzymolytic method by limiting dilution assay. The colony forming efficiency of PDLSC for three experimental groups was determined. Senescence-Associated β-Galactosidase (SA-β-G) expression in the three groups was examined using β-galactosidase staining working solution. Cell cycle and apoptosis of the PDLSC were examined by the flow cytometry. Alkaline phosphatase (ALP) activity was evaluated by ALP staining. The expression of osteoplastic differentiation related genes Runt-related transcription factor-2 (Runx-2), Collagen Type 1 (col-1), and ALP of PDLSC were examined by quantitative real-time RT-PCR.Results The colony forming efficiency of PDLSC in Group A, B and C was 36.67%, 22.67% and 9.33%, respectively, which decreased with donors' age (P<0.05). SA-β-G expression of the senescent PDLSC in group A, B and C were 4.14%, 16.39%, 50.38%, respectively (P<0.05). Cells in G2/S phase was 38.73%, 29.88%, 18.25% (P<0.05), and the apoptosis rate was 1.57%, 4.56%, 5.84% (P<0.05), in group A, B and C respectively. The ALP staining in the three groups decreased with the increase of donors' ages, and the expression of Runx-2, col-1 and ALP decreased gradually from group A to group C (all P<0.05), which indicated the osteogenic differentiation capacity of PDLSC decreased while donor aging.Conclusion Human PDLSC could be successfully isolated from periodontal ligament tissues of different aged donors. However, the proliferation and osteogenic differentiation capacity of PDLSC decreased while donor aging.

[Differential regulation of CCR5 expression on T lymphocytes in healthy donors after mobilization with rhG-CSF and its correlation with aGVHD].

PubMed

Wang, Meng; Ma, Xiang-Juan; Dong, Yu-Jun; Qiu, Zhi-Xiang; Liu, Wei; Li, Yuan; Wang, Mang-Ju; Sun, Yu-Hua; Ren, Han-Yun

2013-08-01

This study was to investigate the differential regulation of CCR5 expression on T cells in healthy donors after mobilization with recombinant human granulocyte colony-stimulating factor (rhG-CSF) and analyze its correlation with acute graft-versus-host disease (aGVHD) so as to understand the possible mechanisms underlying rhG-CSF-induced immune tolerance. Sixty-eight related healthy donor and their corresponding recipient for allogeneic hematopoietic stem cell transplantation (allo-HSCT) were enrolled in this study. The expression of CCR5 on CD4(+) and CD8(+) T cells in the peripheral blood (PB) before and after mobilization were detected by using flow cytometry (FCM) respectively. According to the changes of CCR5 expression on CD4(+) and CD8(+) T cells, the Sixty-two evaluable donors were divided into the downregulated and unchanged/upregulated (non-downregulated) groups, and the incidence of grades II to IV aGVHD in two groups were compared. The results showed that the mean value of CCR5 expression on CD4(+) and CD8(+) T cells in PB was not different significantly after mobilization (P > 0.05). Apparent inconsistency was showed among different individuals. Thirty-four (50%) donors displayed downregulation of CCR5 expression, while 34 (50%) donors manifested unchanged or upregulated CCR5 expression on CD4(+) T cells. CCR5 expression on CD8(+) T cells was downregulated in 42 (61.8%), unchanged or upregulated in 26 (38.3%) donors. The cumulative incidence of grades II to IV aGVHD in the downregulated and non-downregulated groups for CD4(+) T cells were 16.1% and 41.9% (P = 0.032), and recipients with CCR5 downregulation on CD8(+) T cells showed an increased tendency of developing aGVHD (37.8% vs 16.0%, P = 0.065). In conclusion, rhG-CSF mobilization could lead to differential regulation of CCR5 expression on T cells, which might influence the migration of T cells in vivo, decrease T cell trafficking towards GVHD target organs, and thus reduce the incidence of aGVHD after transplantation.

Enhanced uptake of multiple sclerosis-derived myelin by THP-1 macrophages and primary human microglia.

PubMed

Hendrickx, Debbie A E; Schuurman, Karianne G; van Draanen, Michael; Hamann, Jörg; Huitinga, Inge

2014-03-31

The pathological hallmark of multiple sclerosis (MS) is myelin phagocytosis. It remains unclear why microglia and macrophages demyelinate axons in MS, but previously found or yet-unknown changes in the myelin of MS patients could contribute to this process. We therefore studied whether myelin from normal-appearing white matter (NAWM) of MS donors is phagocytosed more efficiently than myelin from control donors. Myelin was isolated from 11 MS and 12 control brain donors and labeled with the pH-sensitive fluorescent dye pHrodo to quantify uptake in lysosomes. Phagocytosis by differentiated THP-1 macrophages and by primary human microglia was quantified with flow cytometry. Whereas myelin uptake by THP-1 macrophages reached a plateau after approximately 24 hours, uptake by primary human microglia showed an almost linear increase over a 72-hour period. Data were statistically analyzed with the Mann-Whitney U test. MS-derived myelin was phagocytosed more efficiently by THP-1 macrophages after 6-hour incubation (P = 0.001 for the percentage of myelin-phagocytosing cells and P = 0.0005 for total myelin uptake) and after 24-hour incubation (P = 0.0006 and P = 0.0001, respectively), and by microglia after 24-hour incubation (P = 0.0106 for total myelin uptake). This enhanced uptake was not due to differences in the oxidation status of the myelin. Interestingly, myelin phagocytosis correlated negatively with the age of myelin donors, whereas the age of microglia donors showed a positive trend with myelin phagocytosis. Myelin isolated from normal-appearing white matter of MS donors was phagocytosed more efficiently than was myelin isolated from control brain donors by both THP-1 macrophages and primary human microglia. These data indicate that changes in MS myelin might precede phagocyte activation and subsequent demyelination in MS. Identifying these myelin changes responsible for enhancing phagocytic ability could be an interesting therapeutic target to prevent or inhibit formation or expansion of MS lesions. Moreover, during aging, microglia enhance their phagocytic capacity for myelin phagocytosis, but myelin reduces its susceptibility for uptake.

Experience of German Red Cross blood donor services with nucleic acid testing: results of screening more than 30 million blood donations for human immunodeficiency virus-1, hepatitis C virus, and hepatitis B virus.

PubMed

Hourfar, Michael K; Jork, Christine; Schottstedt, Volkmar; Weber-Schehl, Marijke; Brixner, Veronika; Busch, Michael P; Geusendam, Geert; Gubbe, Knut; Mahnhardt, Christina; Mayr-Wohlfart, Uschi; Pichl, Lutz; Roth, W Kurt; Schmidt, Michael; Seifried, Erhard; Wright, David J

2008-08-01

The risk of transfusion-transmitted human immunodeficiency virus-1 (HIV-1), hepatitis C virus (HCV), and hepatitis B virus (HBV) infections is predominantly attributable to donations given during the early stage of infection when diagnostic tests may fail. In 1997, nucleic acid amplification technique (NAT)-testing was introduced at the German Red Cross (GRC) blood donor services to reduce this diagnostic window period (WP). A total of 31,524,571 blood donations collected from 1997 through 2005 were screened by minipool NAT, predominantly with pool sizes of 96 donations. These donations cover approximately 80 percent of all the blood collected in Germany during that period. Based on these data, the WP risk in the GRC blood donor population was estimated by using a state-of-the-art mathematic model. During the observation period, 23 HCV, 7 HIV-1, and 43 HBV NAT-only-positive donations were detected. On the basis of these data and estimated pre-NAT infectious WPs, the residual risk per unit transfused was estimated at 1 in 10.88 million for HCV (95% confidence interval [CI], 7.51-19.72 million), 1 in 4.30 million for HIV-1 (95% CI, 2.39-21.37 million), and 1 in 360,000 for HBV (95% CI, 0.19-3.36 million). Based on observed cases of breakthrough infections, the risk of transfusion-related infections may be even lower. The risk of a blood recipient becoming infected with HCV, HIV-1, or HBV has reached an extremely low level. Introduction of individual donation testing for HCV and HIV-1 would have a marginal effect on interception of WP donations.

Genome-wide minor histocompatibility matching as related to the risk of graft-versus-host disease.

PubMed

Martin, Paul J; Levine, David M; Storer, Barry E; Warren, Edus H; Zheng, Xiuwen; Nelson, Sarah C; Smith, Anajane G; Mortensen, Bo K; Hansen, John A

2017-02-09

The risk of acute graft-versus-host disease (GVHD) is higher after allogeneic hematopoietic cell transplantation (HCT) from unrelated donors as compared with related donors. This difference has been explained by increased recipient mismatching for major histocompatibility antigens or minor histocompatibility antigens. In the current study, we used genome-wide arrays to enumerate single nucleotide polymorphisms (SNPs) that produce graft-versus-host (GVH) amino acid coding differences between recipients and donors. We then tested the hypothesis that higher degrees of genome-wide recipient GVH mismatching correlate with higher risks of GVHD after allogeneic HCT. In HLA-genotypically matched sibling recipients, the average recipient mismatching of coding SNPs was 9.35%. Each 1% increase in genome-wide recipient mismatching was associated with an estimated 20% increase in the hazard of grades III-IV GVHD (hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.05-1.37; P = .007) and an estimated 22% increase in the hazard of stage 2-4 acute gut GVHD (HR, 1.22; 95% CI, 1.02-1.45; P = .03). In HLA-A, B, C, DRB1, DQA1, DQB1, DPA1, DPB1-phenotypically matched unrelated recipients, the average recipient mismatching of coding SNPs was 17.3%. The estimated risks of GVHD-related outcomes in HLA-phenotypically matched unrelated recipients were low, relative to the large difference in genome-wide mismatching between the 2 groups. In contrast, the risks of GVHD-related outcomes were higher in HLA-DP GVH-mismatched unrelated recipients than in HLA-matched sibling recipients. Taken together, these results suggest that the increased GVHD risk after unrelated HCT is predominantly an effect of HLA-mismatching. © 2017 by The American Society of Hematology.

Estimation of standard liver volume in Chinese adult living donors.

PubMed

Fu-Gui, L; Lu-Nan, Y; Bo, L; Yong, Z; Tian-Fu, W; Ming-Qing, X; Wen-Tao, W; Zhe-Yu, C

2009-12-01

To determine a formula predicting the standard liver volume based on body surface area (BSA) or body weight in Chinese adults. A total of 115 consecutive right-lobe living donors not including the middle hepatic vein underwent right hemi-hepatectomy. No organs were used from prisoners, and no subjects were prisoners. Donor anthropometric data including age, gender, body weight, and body height were recorded prospectively. The weights and volumes of the right lobe liver grafts were measured at the back table. Liver weights and volumes were calculated from the right lobe graft weight and volume obtained at the back table, divided by the proportion of the right lobe on computed tomography. By simple linear regression analysis and stepwise multiple linear regression analysis, we correlated calculated liver volume and body height, body weight, or body surface area. The subjects had a mean age of 35.97 +/- 9.6 years, and a female-to-male ratio of 60:55. The mean volume of the right lobe was 727.47 +/- 136.17 mL, occupying 55.59% +/- 6.70% of the whole liver by computed tomography. The volume of the right lobe was 581.73 +/- 96.137 mL, and the estimated liver volume was 1053.08 +/- 167.56 mL. Females of the same body weight showed a slightly lower liver weight. By simple linear regression analysis and stepwise multiple linear regression analysis, a formula was derived based on body weight. All formulae except the Hong Kong formula overestimated liver volume compared to this formula. The formula of standard liver volume, SLV (mL) = 11.508 x body weight (kg) + 334.024, may be applied to estimate liver volumes in Chinese adults.

Coupling hydrodynamics with comoving frame radiative transfer. II. Stellar wind stratification in the high-mass X-ray binary Vela X-1

NASA Astrophysics Data System (ADS)

Sander, A. A. C.; Fürst, F.; Kretschmar, P.; Oskinova, L. M.; Todt, H.; Hainich, R.; Shenar, T.; Hamann, W.-R.

2018-02-01

Context. Vela X-1, a prototypical high-mass X-ray binary (HMXB), hosts a neutron star (NS) in a close orbit around an early-B supergiant donor star. Accretion of the donor star's wind onto the NS powers its strong X-ray luminosity. To understand the physics of HMXBs, detailed knowledge about the donor star winds is required. Aims: To gain a realistic picture of the donor star in Vela X-1, we constructed a hydrodynamically consistent atmosphere model describing the wind stratification while properly reproducing the observed donor spectrum. To investigate how X-ray illumination affects the stellar wind, we calculated additional models for different X-ray luminosity regimes. Methods: We used the recently updated version of the Potsdam Wolf-Rayet code to consistently solve the hydrodynamic equation together with the statistical equations and the radiative transfer. Results: The wind flow in Vela X-1 is driven by ions from various elements, with Fe III and S III leading in the outer wind. The model-predicted mass-loss rate is in line with earlier empirical studies. The mass-loss rate is almost unaffected by the presence of the accreting NS in the wind. The terminal wind velocity is confirmed at v∞≈ 600 km s-1. On the other hand, the wind velocity in the inner region where the NS is located is only ≈100 km s-1, which is not expected on the basis of a standard β-velocity law. In models with an enhanced level of X-rays, the velocity field in the outer wind can be altered. If the X-ray flux is too high, the acceleration breaks down because the ionization increases. Conclusions: Accounting for radiation hydrodynamics, our Vela X-1 donor atmosphere model reveals a low wind speed at the NS location, and it provides quantitative information on wind driving in this important HMXB.

Cumulative birth rates with linked assisted reproductive technology cycles.

PubMed

Luke, Barbara; Brown, Morton B; Wantman, Ethan; Lederman, Avi; Gibbons, William; Schattman, Glenn L; Lobo, Rogerio A; Leach, Richard E; Stern, Judy E

2012-06-28

Live-birth rates after treatment with assisted reproductive technology have traditionally been reported on a per-cycle basis. For women receiving continued treatment, cumulative success rates are a more important measure. We linked data from cycles of assisted reproductive technology in the Society for Assisted Reproductive Technology Clinic Outcome Reporting System database for the period from 2004 through 2009 to individual women in order to estimate cumulative live-birth rates. Conservative estimates assumed that women who did not return for treatment would not have a live birth; optimal estimates assumed that these women would have live-birth rates similar to those for women continuing treatment. The data were from 246,740 women, with 471,208 cycles and 140,859 live births. Live-birth rates declined with increasing maternal age and increasing cycle number with autologous, but not donor, oocytes. By the third cycle, the conservative and optimal estimates of live-birth rates with autologous oocytes had declined from 63.3% and 74.6%, respectively, for women younger than 31 years of age to 18.6% and 27.8% for those 41 or 42 years of age and to 6.6% and 11.3% for those 43 years of age or older. When donor oocytes were used, the rates were higher than 60% and 80%, respectively, for all ages. Rates were higher with blastocyst embryos (day of transfer, 5 or 6) than with cleavage embryos (day of transfer, 2 or 3). At the third cycle, the conservative and optimal estimates of cumulative live-birth rates were, respectively, 42.7% and 65.3% for transfer of cleavage embryos and 52.4% and 80.7% for transfer of blastocyst embryos when fresh autologous oocytes were used. Our results indicate that live-birth rates approaching natural fecundity can be achieved by means of assisted reproductive technology when there are favorable patient and embryo characteristics. Live-birth rates among older women are lower than those among younger women when autologous oocytes are used but are similar to the rates among young women when donor oocytes are used. (Funded by the National Institutes of Health and the Society for Assisted Reproductive Technology.).

The financing gaps framework: using need, potential spending and expected spending to allocate development assistance for health

PubMed Central

Haakenstad, Annie; Templin, Tara; Lim, Stephen; Bump, Jesse B; Dieleman, Joseph

2018-01-01

Abstract As growth in development assistance for health levels off, development assistance partners must make allocation decisions within tighter budget constraints. Furthermore, with the advent of comprehensive and comparable burden of disease and health financing estimates, empirical evidence can increasingly be used to direct funding to those most in need. In our ‘financing gaps framework’, we propose a new approach for harnessing information to make decisions about health aid. The framework was designed to be forward-looking, goal-oriented, versatile and customizable to a range of organizational contexts and health aims. Our framework brings together expected health spending, potential health spending and spending need, to orient financing decisions around international health targets. As an example of how the framework could be applied, we develop a case study, focused on global goals for child health. The case study harnesses data from the Global Burden of Disease 2013 Study, Financing Global Health 2015, the WHO Global Health Observatory and National Health Accounts. Funding flows are tied to progress toward the Sustainable Development Goal’s target for reductions in under-five mortality. The flexibility and comprehensiveness of our framework makes it adaptable for use by a diverse set of governments, donors, policymakers and other stakeholders. The framework can be adapted to short‐ or long‐run time frames, cross‐country or subnational scales, and to a number of specific health focus areas. Depending on donor preferences, the framework can be deployed to incentivize local investments in health, ensuring the long-term sustainability of health systems in low- and middle-income countries, while also furnishing international support for progress toward global health goals. PMID:29415240

Design and Feasibility Analysis of a Self-Sustaining Biofiltration System for Removal of Low Concentration N2O Emitted from Wastewater Treatment Plants.

PubMed

Yoon, Hyun; Song, Min Joon; Yoon, Sukhwan

2017-09-19

N 2 O is a potent greenhouse gas and ozone-depletion agent. In this study, a biofiltration system was designed for removal of N 2 O emitted at low concentrations (<200 ppmv) from wastewater treatment plants. The proposed biofiltration system utilizes untreated wastewater from the primary sedimentation basin as the source of electron donor and nutrients and energy requirement is minimized by utilizing gravitational force and pressure differential to direct liquid medium and gas through the biofilter. The experiments performed with laboratory-scale biofilter in two different configurations confirmed the feasibility of the biofiltration system. The biofilter operated with cycling of raw wastewater exhibited up to 94% and 53% removal efficiency with 100 ppmv N 2 O in N 2 and air, respectively, as the feed gas, corroborating that untreated wastewater can serve as a robust source of electron donor and nutrients. The laboratory-scale biofilter operated with a continuous flow-through of synthetic wastewater attained >99.9% removal of N 2 O from N 2 background at the gas flow rate up to 2,000 mL·min -1 and >50% N 2 O removal from air background at the gas flow rate of 200 mL·min -1 . nosZ-containing bacterial genera including Flavobacterium (5.92%), Pseudomonas (4.26%) and Bosea (2.39%) were identified in the biofilm samples collected from the oxic biofilter, indicating these organisms were responsible for N 2 O removal.

Evaluation Influence: The Evaluation Event and Capital Flow in International Development.

PubMed

Bell, David A

2017-12-01

Assessing program effectiveness in human development is central to informing foreign aid policy-making and organizational learning. Foreign aid effectiveness discussions have increasingly given attention to the devaluing effects of aid flow volatility. This study reveals that the external evaluation event influences actor behavior, serving as a volatility-constraining tool. A case study of a multidonor aid development mechanism served examining the influence of an evaluation event when considering anticipatory effects. The qualitative component used text and focus group data combined with individual interview data (organizations n = 10, including 26 individuals). Quantitative data included financial information on all 75 capital investments. The integrated theory of influence and model of alternative mechanisms used these components to identify the linkage between the evaluation event and capital flow volatility. Aid approved in the year of the midterm evaluation was disbursed by the mechanism with low capital volatility. Anticipating the evaluation event influenced behavior resulting in an empirical record that program outcomes were enhanced and the mechanism was an improved organization. Formative evaluations in a development program can trigger activity as an interim process. That activity provides for a more robust assessment of ultimate consequence of interest. Anticipating an evaluation can stimulate donor reality testing. The findings inform and strengthen future research on the influence of anticipating an evaluation. Closely examining activities before, during, and shortly after the evaluation event can aid development of other systematic methods to improve understanding this phenomenon, as well as improve donor effectiveness strategies.

Variational optical flow estimation based on stick tensor voting.

PubMed

Rashwan, Hatem A; Garcia, Miguel A; Puig, Domenec

2013-07-01

Variational optical flow techniques allow the estimation of flow fields from spatio-temporal derivatives. They are based on minimizing a functional that contains a data term and a regularization term. Recently, numerous approaches have been presented for improving the accuracy of the estimated flow fields. Among them, tensor voting has been shown to be particularly effective in the preservation of flow discontinuities. This paper presents an adaptation of the data term by using anisotropic stick tensor voting in order to gain robustness against noise and outliers with significantly lower computational cost than (full) tensor voting. In addition, an anisotropic complementary smoothness term depending on directional information estimated through stick tensor voting is utilized in order to preserve discontinuity capabilities of the estimated flow fields. Finally, a weighted non-local term that depends on both the estimated directional information and the occlusion state of pixels is integrated during the optimization process in order to denoise the final flow field. The proposed approach yields state-of-the-art results on the Middlebury benchmark.

Socio-demographic and fertility-related characteristics and motivations of oocyte donors in eleven European countries.

PubMed

Pennings, G; de Mouzon, J; Shenfield, F; Ferraretti, A P; Mardesic, T; Ruiz, A; Goossens, V

2014-05-01

Do the socio-demographic and fertility-related characteristics and motivations of oocyte donors differ in European countries? The socio-demographic and fertility-related characteristics and motivations of oocyte donors differ considerably across countries. There have been no other international studies comparing the characteristics of oocyte donors. Regarding their motivations, most studies indicate mixed motives. The proposed study was a transversal epidemiological study. Data were collected from 63 voluntarily participating assisted reproduction technology centres practising oocyte donation in 11 European countries (Belgium, Czech Republic, Finland, France, Greece, Poland, Portugal, Russia, Spain, UK and Ukraine). The survey was conducted between September 2011 and June 2012 and ran for 1-6 calendar months depending on the number of cycles of oocyte donation performed at the centre. The sample size was computed in order to allow an estimate of the percentage of a relatively rare characteristic (∼2%) with a precision (95% confidence interval) of 1%. The calculation gave 1118 donors. In total, 1423 forms were obtained from oocyte donors. All consecutive donors in these centres filled out an anonymous questionnaire when they started their hormonal stimulation, asking for their socio-demographic and fertility-related characteristics, their motivations and compensation. Population characteristics were described and compared by country of donation. Motives for donation and mean amount of money were compared between countries and according to the donors characteristics. The socio-demographic and fertility-related characteristics and motivations of oocyte donors varied enormously across European countries. The number of received forms corresponded with a participation rate of 61.9% of the cycles performed by the participating centres. Mean age was 27.4 years. About 49% of donors were fully employed, 16% unemployed and 15% student. The motivation in the total group of donors was 47.8% pure altruism, 33.9% altruism and financial, 10.8% pure financial, 5.9% altruism and own treatment and finally 2% own treatment only. About 15% of the donors were egg sharers (patient donors), mainly from the UK and Poland. Women were donating for the first time in 55.4% of cases, for the second time in 20.3% and for the third time in 12.8%. The motivation to donate was significantly related to being of foreign origin (P < 0.01), age (P < 0.001), living in couple or not (P < 0.01), level of education (P < 0.001) and number of donations (P < 0.001). The amount of compensation differed considerably between centres and/or countries. The general donor profile in this study was a well-educated, 27-year-old woman living with her partner and child who mainly donated to help others. The selection of clinics in some countries and the limited participation rate may have led to a bias in donor characteristics. A possible effect of social desirability in the answers by the donors should be taken into account. The diversity of the donor population reflects the differences in European legislation (for example, on anonymity and payment) and economic circumstances. The differences in systems of reimbursement/payment demonstrate the need to have a thorough discussion on the specific meaning of these terms. The study was funded by the European Society for Human Reproduction and Embryology. The authors declare no conflicting interests.

Estimated probabilities, volumes, and inundation areas depths of potential postwildfire debris flows from Carbonate, Slate, Raspberry, and Milton Creeks, near Marble, Gunnison County, Colorado

USGS Publications Warehouse

Stevens, Michael R.; Flynn, Jennifer L.; Stephens, Verlin C.; Verdin, Kristine L.

2011-01-01

During 2009, the U.S. Geological Survey, in cooperation with Gunnison County, initiated a study to estimate the potential for postwildfire debris flows to occur in the drainage basins occupied by Carbonate, Slate, Raspberry, and Milton Creeks near Marble, Colorado. Currently (2010), these drainage basins are unburned but could be burned by a future wildfire. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of postwildfire debris-flow occurrence and debris-flow volumes for drainage basins occupied by Carbonate, Slate, Raspberry, and Milton Creeks near Marble. Data for the postwildfire debris-flow models included drainage basin area; area burned and burn severity; percentage of burned area; soil properties; rainfall total and intensity for the 5- and 25-year-recurrence, 1-hour-duration-rainfall; and topographic and soil property characteristics of the drainage basins occupied by the four creeks. A quasi-two-dimensional floodplain computer model (FLO-2D) was used to estimate the spatial distribution and the maximum instantaneous depth of the postwildfire debris-flow material during debris flow on the existing debris-flow fans that issue from the outlets of the four major drainage basins. The postwildfire debris-flow probabilities at the outlet of each drainage basin range from 1 to 19 percent for the 5-year-recurrence, 1-hour-duration rainfall, and from 3 to 35 percent for 25-year-recurrence, 1-hour-duration rainfall. The largest probabilities for postwildfire debris flow are estimated for Raspberry Creek (19 and 35 percent), whereas estimated debris-flow probabilities for the three other creeks range from 1 to 6 percent. The estimated postwildfire debris-flow volumes at the outlet of each creek range from 7,500 to 101,000 cubic meters for the 5-year-recurrence, 1-hour-duration rainfall, and from 9,400 to 126,000 cubic meters for the 25-year-recurrence, 1-hour-duration rainfall. The largest postwildfire debris-flow volumes were estimated for Carbonate Creek and Milton Creek drainage basins, for both the 5- and 25-year-recurrence, 1-hour-duration rainfalls. Results from FLO-2D modeling of the 5-year and 25-year recurrence, 1-hour rainfalls indicate that the debris flows from the four drainage basins would reach or nearly reach the Crystal River. The model estimates maximum instantaneous depths of debris-flow material during postwildfire debris flows that exceeded 5 meters in some areas, but the differences in model results between the 5-year and 25-year recurrence, 1-hour rainfalls are small. Existing stream channels or topographic flow paths likely control the distribution of debris-flow material, and the difference in estimated debris-flow volume (about 25 percent more volume for the 25-year-recurrence, 1-hour-duration rainfall compared to the 5-year-recurrence, 1-hour-duration rainfall) does not seem to substantially affect the estimated spatial distribution of debris-flow material. Historically, the Marble area has experienced periodic debris flows in the absence of wildfire. This report estimates the probability and volume of debris flow and maximum instantaneous inundation area depths after hypothetical wildfire and rainfall. This postwildfire debris-flow report does not address the current (2010) prewildfire debris-flow hazards that exist near Marble.

EFFECT OF DIETARY FOLATE DEFICIENCY ON ARSENIC GENOTOXICITY IN MICE

EPA Science Inventory

Arsenic, a human carcinogen found in drinking water supplies throughout the world, is clastogenic in human and rodent cells. An estimated ten percent of Americans are deficient in folate, a methyl donor necessary for normal nucleotide metabolism, DNA synthesis, and DNA methylatio...

Lack of a peroxiredoxin suppresses the lethality of cells devoid of electron donors by channelling electrons to oxidized ribonucleotide reductase.

PubMed

Boronat, Susanna; Domènech, Alba; Carmona, Mercè; García-Santamarina, Sarela; Bañó, M Carmen; Ayté, José; Hidalgo, Elena

2017-06-01

The thioredoxin and glutaredoxin pathways are responsible of recycling several enzymes which undergo intramolecular disulfide bond formation as part of their catalytic cycles such as the peroxide scavengers peroxiredoxins or the enzyme ribonucleotide reductase (RNR). RNR, the rate-limiting enzyme of deoxyribonucleotide synthesis, is an essential enzyme relying on these electron flow cascades for recycling. RNR is tightly regulated in a cell cycle-dependent manner at different levels, but little is known about the participation of electron donors in such regulation. Here, we show that cytosolic thioredoxins Trx1 and Trx3 are the primary electron donors for RNR in fission yeast. Unexpectedly, trx1 transcript and Trx1 protein levels are up-regulated in a G1-to-S phase-dependent manner, indicating that the supply of electron donors is also cell cycle-regulated. Indeed, genetic depletion of thioredoxins triggers a DNA replication checkpoint ruled by Rad3 and Cds1, with the final goal of up-regulating transcription of S phase genes and constitutive RNR synthesis. Regarding the thioredoxin and glutaredoxin cascades, one combination of gene deletions is synthetic lethal in fission yeast: cells lacking both thioredoxin reductase and cytosolic dithiol glutaredoxin. We have isolated a suppressor of this lethal phenotype: a mutation at the Tpx1-coding gene, leading to a frame shift and a loss-of-function of Tpx1, the main client of electron donors. We propose that in a mutant strain compromised in reducing equivalents, the absence of an abundant and competitive substrate such as the peroxiredoxin Tpx1 has been selected as a lethality suppressor to favor RNR function at the expense of the non-essential peroxide scavenging function, to allow DNA synthesis and cell growth.

Prenatal tolerance induction: relationship between cell dose, marrow T-cells, chimerism, and tolerance.

PubMed

Chen, Jeng-Chang; Chang, Ming-Ling; Huang, Shiu-Feng; Chang, Pei-Yeh; Muench, Marcus O; Fu, Ren-Huei; Ou, Liang-Shiou; Kuo, Ming-Ling

2008-01-01

It was reported that the dose of self-antigens can determine the consequence of deletional tolerance and donor T cells are critical for tolerance induction in mixed chimeras. This study aimed at assessing the effect of cell doses and marrow T cells on engraftment and tolerance induction after prenatal bone marrow transplantation. Intraperitoneal cell transplantation was performed in FVB/N (H-2K(q)) mice at gestational day 14 with escalating doses of adult C57BL/6 (H-2K(b)) marrows. Peripheral chimerism was examined postnatally by flow cytometry and tolerance was tested by skin transplantation. Transplantation of light-density marrow cells showed a dose response. High-level chimerism emerged with a threshold dose of 5.0 x 10(6) and host leukocytes could be nearly replaced at a dose of 7.5-10.0 x 10(6). High-dose transplants conferred a steady long-lasting donor-specific tolerance but were accompanied by >50% incidence of graft-versus-host disease. Depletion of marrow T cells lessened graft-versus-host disease to the detriment of engraftment. With low-level chimerism, tolerance was a graded phenomenon dependent upon the level of chimerism. Durable chimerism within 6 months required a threshold of > or = 2% chimerism at 1 month of age and predicted a 50% chance of long-term tolerance, whereas transient chimerism (<2%) only caused hyporesponsiveness to the donor. Tolerance induction did not succeed without peripheral chimerism even if a large amount of injected donor cells persisted in the peritoneum. Neither did an increase in cell doses or donor T-cell contents benefit skin graft survivals unless it had substantially improved peripheral chimerism. Thus, peripheral chimerism level can be a simple and straightforward test to predict the degree of prenatal immune tolerance.

Process Improvement in Thoracic Donor Organ Procurement: Implementation of a Donor Assessment Checklist.

PubMed

Loor, Gabriel; Shumway, Sara J; McCurry, Kenneth R; Keshavamurthy, Suresh; Hussain, Syed; Weide, Garry D; Spratt, John R; Al Salihi, Mazin; Koch, Colleen G

2016-12-01

Donor organs are often procured by junior staff in stressful, unfamiliar environments where a single adverse event can be catastrophic. A formalized checklist focused on preprocedural processes related to thoracic donor organ procurement could improve detection and prevention of near miss events. A checklist was developed centered on patient identifiers, organ compatibility and quality, and team readiness. It went through five cycles of feedback and revision using a panel of expert procurement surgeons. Educational in-service sessions were held on the use of the checklist as well as best organ assessment practices. Near miss events before the survey were tallied by retrospective review of 20 procurements, and near misses after checklist implementation were prospectively recorded. We implemented the checklist for 40 donor lung and heart procurements: 20 from Cleveland Clinic and 20 from the University of Minnesota. A final survey assessment was used to determine ease of use. Nine near miss events were reported in 20 procurements before use of the checklist. Thirty-one near miss events of 40 organ procurements were identified and potentially prevented by the checklist. Eighty-seven percent of fellows found the checklist to be unobtrusive to work flow, and 100% believed its use should be mandatory. Mortality was the same before and after implementation of the checklist despite increased patient volumes. Implementation of a simple checklist for use during thoracic organ procurement uncovered a substantial number of near miss events. A preprocedural checklist for all thoracic organ transplants in the United States and abroad is feasible and would likely reduce adverse events. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

The 24-hour normothermic machine perfusion of discarded human liver grafts.

PubMed

Vogel, Thomas; Brockmann, Jens G; Quaglia, Alberto; Morovat, Alireza; Jassem, Wayel; Heaton, Nigel D; Coussios, Constantin C; Friend, Peter J

2017-02-01

Donor organ shortage necessitates use of less than optimal donor allografts for transplantation. The current cold storage preservation technique fails to preserve marginal donor grafts sufficiently. Evidence from large animal experiments suggests superiority of normothermic machine preservation (NMP) of liver allografts. In this study, we analyze discarded human liver grafts that underwent NMP for the extended period of 24 hours. Thirteen human liver grafts which had been discarded for transplantation were entered into this study. Perfusion was performed with an automated device using an oxygenated, sanguineous perfusion solution at normothermia. Automated control was incorporated for temperature-, flow-, and pressure-regulation as well as oxygenation. All livers were perfused for 24 hours; parameters of biochemical and synthetic liver function as well as histological parameters of liver damage were analyzed. Livers were stratified for expected viability according to the donor's medical history, procurement data, and their macroscopic appearance. Normothermic perfusion preservation of human livers for 24 hours was shown to be technically feasible. Human liver grafts, all of which had been discarded for transplantation, showed levels suggesting organ viability with respect to metabolic and synthetic liver function (to varying degrees). There was positive correlation between instantly available perfusion parameters and generally accepted predictors of posttransplant graft survival. In conclusion, NMP is feasible reliably for periods of at least 24 hours, even in highly suboptimal donor organs. Potential benefits include not only viability testing (as suggested in recent clinical implementations), but also removal of the time constraints associated with the utilization of high-risk livers, and recovery of ischemic and other preretrieval injuries (possibly by enabling therapeutic strategies during NMP). Liver Transplantation 23 207-220 2017 AASLD. © 2016 by the American Association for the Study of Liver Diseases.

Estimating the cost of blood: past, present, and future directions.

PubMed

Shander, Aryeh; Hofmann, Axel; Gombotz, Hans; Theusinger, Oliver M; Spahn, Donat R

2007-06-01

Understanding the costs associated with blood products requires sophisticated knowledge about transfusion medicine and is attracting the attention of clinical and administrative healthcare sectors worldwide. To improve outcomes, blood usage must be optimized and expenditures controlled so that resources may be channeled toward other diagnostic, therapeutic, and technological initiatives. Estimating blood costs, however, is a complex undertaking, surpassing simple supply versus demand economics. Shrinking donor availability and application of a precautionary principle to minimize transfusion risks are factors that continue to drive the cost of blood products upward. Recognizing that historical accounting attempts to determine blood costs have varied in scope, perspective, and methodology, new approaches have been initiated to identify all potential cost elements related to blood and blood product administration. Activities are also under way to tie these elements together in a comprehensive and practical model that will be applicable to all single-donor blood products without regard to practice type (e.g., academic, private, multi- or single-center clinic). These initiatives, their rationale, importance, and future directions are described.

Weak hydrogen bond topology in 1,1-difluoroethane dimer: A rotational study

NASA Astrophysics Data System (ADS)

Chen, Junhua; Zheng, Yang; Wang, Juan; Feng, Gang; Xia, Zhining; Gou, Qian

2017-09-01

The rotational spectrum of the 1,1-difluoroethane dimer has been investigated by pulsed-jet Fourier transform microwave spectroscopy. Two most stable isomers have been detected, which are both stabilized by a network of three C—H⋯F—C weak hydrogen bonds: in the most stable isomer, two difluoromethyl C—H groups and one methyl C—H group act as the weak proton donors whilst in the second isomer, two methyl C—H groups and one difluoromethyl C—H group act as the weak proton donors. For the global minimum, the measurements have also been extended to its four 13C isotopologues in natural abundance, allowing a precise, although partial, structural determination. Relative intensity measurements on a set of μa-type transitions allowed estimating the relative population ratio of the two isomers as NI/NII ˜ 6/1 in the pulsed jet, indicating a much larger energy gap between these two isomers than that expected from ab initio calculation, consistent with the result from pseudo-diatomic dissociation energies estimation.

Flow Durations, Low-Flow Frequencies, and Monthly Median Flows for Selected Streams in Connecticut through 2005

USGS Publications Warehouse

Ahearn, Elizabeth A.

2008-01-01

Flow durations, low-flow frequencies, and monthly median streamflows were computed for 91 continuous-record, streamflow-gaging stations in Connecticut with 10 or more years of record. Flow durations include the 99-, 98-, 97-, 95-, 90-, 85-, 80-, 75-, 70-, 60-, 50-, 40-, 30-, 25-, 20-, 10-, 5-, and 1-percent exceedances. Low-flow frequencies include the 7-day, 10-year (7Q10) low flow; 7-day, 2-year (7Q2) low flow; and 30-day, 2-year (30Q2) low flow. Streamflow estimates were computed for each station using data for the period of record through water year 2005. Estimates of low-flow statistics for 7 short-term (operated between 3 and 10 years) streamflow-gaging stations and 31 partial-record sites were computed. Low-flow estimates were made on the basis of the relation between base flows at a short-term station or partial-record site and concurrent daily mean streamflows at a nearby index station. The relation is defined by the Maintenance of Variance Extension, type 3 (MOVE.3) method. Several short-term stations and partial-record sites had poorly defined relations with nearby index stations; therefore, no low-flow statistics were derived for these sites. The estimated low-flow statistics for the short-term stations and partial-record sites include the 99-, 98-, 97-, 95-, 90-, and 85-percent flow durations; the 7-day, 10-year (7Q10) low flow; 7-day, 2-year (7Q2) low flow; and 30-day, 2-year (30Q2) low-flow frequencies; and the August median flow. Descriptive information on location and record length, measured basin characteristics, index stations correlated to the short-term station and partial-record sites, and estimated flow statistics are provided in this report for each station. Streamflow estimates from this study are stored on USGS's World Wide Web application 'StreamStats' (http://water.usgs.gov/osw/streamstats/connecticut.html).

Biofilm development in a hotspot of mixing between shallow and deep groundwater in a fractured aquifer: field evidence from joint flow, chemical and microbiological measurements

NASA Astrophysics Data System (ADS)

Bochet, O.; Dufresne, A.; Pédrot, M.; Chatton, E.; Labasque, T.; Ben Maamar, S.; Burté, L.; de la Bernardie, J.; Guihéneuf, N.; Lavenant, N.; Petton, C.; Bour, O.; Aquilina, L.; Le Borgne, T.

2015-12-01

Biofilms play a major role in controlling the fluxes and reactivity of chemical species transported in hydro-logical systems. Micro-organisms require both electron donors and electron acceptors for cellular growth, proliferation and maintenance of their metabolic functions. The mechanisms controlling these reactions derive from the interactions occurring at the micro-scale that depend on mineral compositions, the biota of subsurface environment, but also fluid mixing, which determines the local concentrations of nutriments, electron donors and electron acceptors. Hence, mixing zones between oxygen and nutriment rich shallow groundwater and mineralized deep groundwater are often considered as potential hotspots of microbial activity, although relatively few field data document flow distributions, transport properties, chemical gradients and micro-organisms distributions across these mixing interfaces. Here we investigate the origin of a localized biofilm development observed in the fractured granite aquifer at the Ploemeur observatory (H+ network hplus.ore.fr).This biofilm composed of ferro-oxidizing bacteria is observed in an 130m deep artesian well. Borehole video logs show an important colonization of the well by the biofilm in the shallower part (0 to 60m), while it is inexistent in the deeper part (60 to 130m). As flow is localized in a few deep and shallow fractures, we presume that the spatial distribution of biofilm is controlled by mixing between shallow and deep groundwater. To verify this hypothesis we conducted a field campaign with joint characterization of the flow and chemical composition of water flowing from the different fractures, as well as the microbiological composition of the biofilm at different depth, using pyrosequencing techniques. We will discuss in this presentation the results of this interdisciplinary dataset and their implications for the occurrence of hotspots of microbiological activity in the subsurface.

Estimates of streamflow characteristics for selected small streams, Baker River basin, Washington

USGS Publications Warehouse

Williams, John R.

1987-01-01

Regression equations were used to estimate streamflow characteristics at eight ungaged sites on small streams in the Baker River basin in the North Cascade Mountains, Washington, that could be suitable for run-of-the-river hydropower development. The regression equations were obtained by relating known streamflow characteristics at 25 gaging stations in nearby basins to several physical and climatic variables that could be easily measured in gaged or ungaged basins. The known streamflow characteristics were mean annual flows, 1-, 3-, and 7-day low flows and high flows, mean monthly flows, and flow duration. Drainage area and mean annual precipitation were not the most significant variables in all the regression equations. Variance in the low flows and the summer mean monthly flows was reduced by including an index of glacierized area within the basin as a third variable. Standard errors of estimate of the regression equations ranged from 25 to 88%, and the largest errors were associated with the low flow characteristics. Discharge measurements made at the eight sites near midmonth each month during 1981 were used to estimate monthly mean flows at the sites for that period. These measurements also were correlated with concurrent daily mean flows from eight operating gaging stations. The correlations provided estimates of mean monthly flows that compared reasonably well with those estimated by the regression analyses. (Author 's abstract)

Donor information based prediction of early allograft dysfunction and outcome in liver transplantation.

PubMed

Hoyer, Dieter P; Paul, Andreas; Gallinat, Anja; Molmenti, Ernesto P; Reinhardt, Renate; Minor, Thomas; Saner, Fuat H; Canbay, Ali; Treckmann, Jürgen W; Sotiropoulos, Georgios C; Mathé, Zoltan

2015-01-01

Poor initial graft function was recently newly defined as early allograft dysfunction (EAD) [Olthoff KM, Kulik L, Samstein B, et al. Validation of a current definition of early allograft dysfunction in liver transplant recipients and analysis of risk factors. Liver Transpl 2010; 16: 943]. Aim of this analysis was to evaluate predictive donor information for development of EAD. Six hundred and seventy-eight consecutive adult patients (mean age 51.6 years; 60.3% men) who received a primary liver transplantation (LT) (09/2003-12/2011) were included. Standard donor data were correlated with EAD and outcome by univariable/multivariable logistic regression and Cox proportional hazards to identify prognostic donor factors after adjustment for recipient confounders. Estimates of relevant factors were utilized for construction of a new continuous risk index to develop EAD. 38.7% patients developed EAD. 30-day survival of grafts with and without EAD was 59.8% and 89.7% (P < 0.0001). 30-day survival of patients with and without EAD was 68.5% and 93.1% (P < 0.0001) respectively. Donor body mass index (P = 0.0112), gGT (P = 0.0471), macrosteatosis (P = 0.0006) and cold ischaemia time (CIT) (P = 0.0031) were predictors of EAD. Internal cross validation showed a high predictive value (c-index = 0.622). Early allograft dysfunction correlates with early results of LT and can be predicted by donor data only. The newly introduced risk index potentially optimizes individual decisions to accept/decline high risk organs. Outcome of these organs might be improved by shortening CIT. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Risk Factors for Human Immunodeficiency Virus Infection among Brazilian Blood Donors; a Multicenter Case-Control Study Using Audio Computer-Assisted Structured-Interviews

PubMed Central

de Almeida-Neto, Cesar; Goncalez, Thelma T.; Birch, Rebecca Jeffries; de Carvalho, Silvia Maia F.; Capuani, Ligia; Leão, Silvana Carneiro; Miranda, Carolina; Rocha, Pedro Capuani; Carneiro-Proietti, Anna Barbara; Johnson, Bryce R.; Wright, David J.; Murphy, Edward L.; Custer, Brian

2013-01-01

Background Although risk factors for HIV infection are known, it is important for blood centers to understand local epidemiology and disease transmission patterns. Current risk factors for HIV infection in blood donors in Brazil were assessed. Methods A case-control study was conducted at large public blood centers located in four major cities between April 2009 – March 2011. Cases were persons whose donations were confirmed positive by enzyme immunoassays followed by Western Blot confirmation. Audio computer-assisted structured-interviews (ACASI) were completed by all cases and controls. Multivariable logistic regression was used to estimate adjusted odds ratios (AORs) and associated 95% confidence intervals (CIs). Results There were 341 cases, including 47 with recently-acquired infection, and 791 controls. Disclosed risk factors for both females and males were sex with an HIV-positive person (adjusted odds ratio (AOR) 11.3, 95% CI [4.1, 31.7]) and being an IVDU or sexual partner of an IVDU (AOR 4.65 [1.8, 11.7]). For female blood donors, additional risk factors were having male sex partners who also are MSM (AOR 13.5 [3.1, 59.8]), and having unprotected sex with multiple sexual partners (AOR 5.19 [2.1, 12.9]). The primary risk factor for male blood donors was MSM activity (AOR 21.6 [8.8, 52.9.]). Behaviors associated with recently-acquired HIV were being a MSM or sex partner of MSM (13.82, [4.7, 40.3]), and IVDU (11.47, [3.0, 43.2]). Conclusion Risk factors in blood donors parallel those in the general population in Brazil. Identified risk factors suggest that donor compliance with selection procedures at the participating blood centers is inadequate. PMID:23517235

Spectral engineering in π-conjugated polymers with intramolecular donor-acceptor interactions.

PubMed

Beaujuge, Pierre M; Amb, Chad M; Reynolds, John R

2010-11-16

With the development of light-harvesting organic materials for solar cell applications and molecular systems with fine-tuned colors for nonemissive electrochromic devices (e.g., smart windows, e-papers), a number of technical challenges remain to be overcome. Over the years, the concept of "spectral engineering" (tailoring the complex interplay between molecular physics and the various optical phenomena occurring across the electromagnetic spectrum) has become increasingly relevant in the field of π-conjugated organic polymers. Within the spectral engineering toolbox, the "donor-acceptor" approach uses alternating electron-rich and electron-deficient moieties along a π-conjugated backbone. This approach has proved especially valuable in the synthesis of dual-band and broadly absorbing chromophores with useful photovoltaic and electrochromic properties. In this Account, we highlight and provide insight into a present controversy surrounding the origin of the dual band of absorption sometimes encountered in semiconducting polymers structured using the "donor-acceptor" approach. Based on empirical evidence, we provide some schematic representations to describe the possible mechanisms governing the evolution of the two-band spectral absorption observed on varying the relative composition of electron-rich and electron-deficient substituents along the π-conjugated backbone. In parallel, we draw attention to the choice of the method employed to estimate and compare the absorption coefficients of polymer chromophores exhibiting distinct repeat unit lengths, and containing various extents of solubilizing side-chains along their backbone. Finally, we discuss the common assumption that "donor-acceptor" systems should have systematically lower absorption coefficients than their "all-donor" counterparts. The proposed models point toward important theoretical parameters which could be further explored at the macromolecular level to help researchers take full advantage of the complex interactions taking place in π-conjugated polymers with intramolecular "donor-acceptor" characteristics.

Renal transplantation across the donor-specific antibody barrier: Graft outcome and cancer risk after desensitization therapy.

PubMed

Yang, Ching-Yao; Lee, Chih-Yuan; Yeh, Chi-Chuan; Tsai, Meng-Kun

2016-06-01

Desensitization regimens including use of intravenous immune globulin and rituximab have been reported to overcome renal transplant hyperacute rejection. A retrospective case-control study was performed to assess the results and complications of renal transplantation with desensitization therapy for donor-specific antibody (DSA) in a transplant center in Asia, where donor exchange was usually not allowed. Between January 2007 and December 2013, 22 patients with DSA received live-donor renal transplantation after desensitization (DSA group). During the same period, the DSA group was compared to the NSA group (152 renal transplants) who had no specific antibody to the donors (66 from deceased donors and 86 from living relatives). Rejection, renal function, graft and patient survival rates, infection, and cancer incidence were reviewed and analyzed from medical records. The DSA group (46.8%) had significantly higher acute rejection rates than the NSA group (13.7%) at the 1-year follow-up. The estimated renal function, 5-year graft, and patient survival rates were comparable between the groups. The DSA group (19.6%) had significantly higher 5-year de novo cancer incidence than the NSA group (8.5%; p = 0.028); three patients of the DSA group developed urothelial carcinoma 17.0 ± 3.0 months after transplantation. By using stepwise Cox regression analysis, desensitization therapy was identified as the sole independent risk factor for post-transplant urothelial carcinoma. When compared to renal transplantation without DSA, desensitization therapy for DSA resulted in equivalent renal transplant outcome but potentially increased risk of urothelial carcinoma after transplantation. Copyright © 2015. Published by Elsevier B.V.

Entrepreneurial ventures and whole-body donations: a regional perspective from the United States.

PubMed

Anteby, Michel; Hyman, Mikell

2008-02-01

Human cadavers are crucial to medical science. While the debate on how to secure sufficient cadavers has focused primarily on donors' behaviors, procuring organizations' roles in increasing donations remain less explored. The United States offers a unique setting in which to examine this question since entrepreneurial ventures supplying cadavers for medical science have recently emerged alongside traditional academic-housed programs, raising both hopes and fears about their impact on whole-body donations. To assess their potential impact, an archival survey of voluntary, in-state whole-body donors to two programs procuring in the same U.S. state was conducted. The programs' specimen recipients were also analyzed. One program is academic-housed and the other is an entrepreneurial venture. Both offered equal levels of financial support to donating parties. Eighty donations and 120 specimen shipping invoices from 2005 were analyzed in each program. Donations to the two programs did not significantly differ in terms of donors' sex, marital status, maximum educational level, and estimated hourly wage. The entrepreneurial venture's donors were, however, significantly younger, more likely to be from a minority group, and more likely to have died from cancer. For-profit organizations, continuing medical training organizations, and medical device companies were more likely recipients of the entrepreneurial venture's specimens. Non-profit and academic organizations were more likely recipients of the academic-housed program's specimens. These findings suggest that although the programs procured from a somewhat similar pool of donors, they also complemented one another. The entrepreneurial program procured donations that the academic-housed program often did not attract. Specimen recipients' distinct demands partly explain these procurement behaviors. Thus, organizational efforts to meet demands seem to shape the supply. Examining organizations alongside donors might provide new answers to secure donations.

Resection plane-dependent error in computed tomography volumetry of the right hepatic lobe in living liver donors

PubMed Central

Kwon, Heon-Ju; Kim, Bohyun; Kim, So Yeon; Lee, Chul Seung; Lee, Jeongjin; Song, Gi Won; Lee, Sung Gyu

2018-01-01

Background/Aims Computed tomography (CT) hepatic volumetry is currently accepted as the most reliable method for preoperative estimation of graft weight in living donor liver transplantation (LDLT). However, several factors can cause inaccuracies in CT volumetry compared to real graft weight. The purpose of this study was to determine the frequency and degree of resection plane-dependent error in CT volumetry of the right hepatic lobe in LDLT. Methods Forty-six living liver donors underwent CT before donor surgery and on postoperative day 7. Prospective CT volumetry (VP) was measured via the assumptive hepatectomy plane. Retrospective liver volume (VR) was measured using the actual plane by comparing preoperative and postoperative CT. Compared with intraoperatively measured weight (W), errors in percentage (%) VP and VR were evaluated. Plane-dependent error in VP was defined as the absolute difference between VP and VR. % plane-dependent error was defined as follows: |VP–VR|/W∙100. Results Mean VP, VR, and W were 761.9 mL, 755.0 mL, and 696.9 g. Mean and % errors in VP were 73.3 mL and 10.7%. Mean error and % error in VR were 64.4 mL and 9.3%. Mean plane-dependent error in VP was 32.4 mL. Mean % plane-dependent error was 4.7%. Plane-dependent error in VP exceeded 10% of W in approximately 10% of the subjects in our study. Conclusions There was approximately 5% plane-dependent error in liver VP on CT volumetry. Plane-dependent error in VP exceeded 10% of W in approximately 10% of LDLT donors in our study. This error should be considered, especially when CT volumetry is performed by a less experienced operator who is not well acquainted with the donor hepatectomy plane. PMID:28759989

Assessment of simulated high-dose partial-body irradiation by PCC-R assay.

PubMed

Romero, Ivonne; García, Omar; Lamadrid, Ana I; Gregoire, Eric; González, Jorge E; Morales, Wilfredo; Martin, Cécile; Barquinero, Joan-Francesc; Voisin, Philippe

2013-09-01

The estimation of the dose and the irradiated fraction of the body is important information in the primary medical response in case of a radiological accident. The PCC-R assay has been developed for high-dose estimations, but little attention has been given to its applicability for partial-body irradiations. In the present work we estimated the doses and the percentage of the irradiated fraction in simulated partial-body radiation exposures at high doses using the PCC-R assay. Peripheral whole blood of three healthy donors was exposed to doses from 0-20 Gy, with ⁶⁰Co gamma radiation. To simulate partial body irradiations, irradiated and non-irradiated blood was mixed to obtain proportions of irradiated blood from 10-90%. Lymphocyte cultures were treated with Colcemid and Calyculin-A before harvest. Conventional and triage scores were performed for each dose, proportion of irradiated blood and donor. The Papworth's u test was used to evaluate the PCC-R distribution per cell. A dose-response relationship was fitted according to the maximum likelihood method using the frequencies of PCC-R obtained from 100% irradiated blood. The dose to the partially irradiated blood was estimated using the Contaminated Poisson method. A new D₀ value of 10.9 Gy was calculated and used to estimate the initial fraction of irradiated cells. The results presented here indicate that by PCC-R it is possible to distinguish between simulated partial- and whole-body irradiations by the u-test, and to accurately estimate the dose from 10-20 Gy, and the initial fraction of irradiated cells in the interval from 10-90%.

KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors

PubMed Central

Lentine, Krista L.; Kasiske, Bertram L.; Levey, Andrew S.; Adams, Patricia L.; Alberú, Josefina; Bakr, Mohamed A.; Gallon, Lorenzo; Garvey, Catherine A.; Guleria, Sandeep; Li, Philip Kam-Tao; Segev, Dorry L.; Taler, Sandra J.; Tanabe, Kazunari; Wright, Linda; Zeier, Martin G.; Cheung, Michael; Garg, Amit X.

2017-01-01

Abstract The 2017 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors is intended to assist medical professionals who evaluate living kidney donor candidates and provide care before, during and after donation. The guideline development process followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach and guideline recommendations are based on systematic reviews of relevant studies that included critical appraisal of the quality of the evidence and the strength of recommendations. However, many recommendations, for which there was no evidence or no systematic search for evidence was undertaken by the Evidence Review Team, were issued as ungraded expert opinion recommendations. The guideline work group concluded that a comprehensive approach to risk assessment should replace decisions based on assessments of single risk factors in isolation. Original data analyses were undertaken to produce a “proof-in-concept” risk-prediction model for kidney failure to support a framework for quantitative risk assessment in the donor candidate evaluation and defensible shared decision making. This framework is grounded in the simultaneous consideration of each candidate's profile of demographic and health characteristics. The processes and framework for the donor candidate evaluation are presented, along with recommendations for optimal care before, during, and after donation. Limitations of the evidence are discussed, especially regarding the lack of definitive prospective studies and clinical outcome trials. Suggestions for future research, including the need for continued refinement of long-term risk prediction and novel approaches to estimating donation-attributable risks, are also provided. In citing this document, the following format should be used: Kidney Disease: Improving Global Outcomes (KDIGO) Living Kidney Donor Work Group. KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors. Transplantation. 2017;101(Suppl 8S):S1–S109. PMID:28742762

Contribution of HLA-A/B/C/DRB1/DQB1 common haplotypes to donor search outcome in unrelated hematopoietic stem cell transplantation.

PubMed

Pédron, Béatrice; Guérin-El Khourouj, Valérie; Dalle, Jean-Hugues; Ouachée-Chardin, Marie; Yakouben, Karima; Corroyez, France; Auvrignon, Anne; Petit, Arnaud; Landman-Parker, Judith; Leverger, Guy; Baruchel, André; Sterkers, Ghislaine

2011-11-01

In unrelated hematopoietic stem cell transplantation (HSCT), the prediction of donor search outcome at the time of search initiation is of great value for the physicians to delineate the strategy of patient care. The probability of finding an unrelated donor is high for patients who carry at least 1 of the 10 most common HLA haplotypes in Caucasians. As only 10% to 20% patients respond to this criterion, here we aimed at finding additional common haplotypes to improve the prediction of a successful search. HLA broad HLA-A/B/DRB1 haplotypes that were observed with frequencies ≥0.19% in patient families of European origin and that split into ≤2 predominant 4-digit HLA-A/B/C/DRB1/DQB1 haplotypes were considered as common. Carriage of at least 1 of those in 168 patients of various geographic areas with no family donor was confronted to the chance of finding ≥9/10 HLA-matched unrelated donors. Fifty common 4-digit haplotypes were identified. A higher (P < 5 × 10(-6)) chance of finding a suitable donor was found for 55 of 170 (32%) recipients that carried at least 1 of these common haplotypes. Up to now, estimates classified patients into ≥3 groups of probability with ≥1 intermediate group of poor utility for the clinicians. Considering carriage of these common haplotypes together with the frequencies of alleles and of B/C and DRB1/DQB1 associations, which are carried by patient HLA haplotypes, we could classify the patients into 2 groups of probability with a 98% and 26% chance of finding a donor, respectively. Prediction of search outcome could be improved by including the 50 most common HLA haplotypes in the current approaches. Copyright © 2011 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.