The organ transplantation act and recent trends in Korea.

PubMed

Joo, Ho No

2013-03-01

The Organ Transplantation Act, including transplantation of organs from brain-dead donors, entered into force in Korea on February 9, 2000. This article introduces the Organ Transplantation Act, focusing on scope of the Act, determination of brain death, removal of organs from brain-dead or deceased donors, removal from living donors, organ allocation, and prohibition of trade in human organs. Especially, some primary ethical dilemmas surrounding organ allocation arise from the shortage of available organs. The primary ethical problems surrounding organ allocation are as follows. A key purpose of the organ donation incentive system is to increase the number of organ transplants from brain-dead donors. In particular, the priority for kidney patient was allowed in consideration of doctor's strong desire to increase the brain-dead donors. Also, the organ allocation criteria based on the organ donation incentive system appear unfair, especially for the kidney patient, because the criteria do not fit the principles of distributive justice. In the future, the organ donation incentive system itself may need to be reexamined.

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.

Dual Kidney Allocation Score: A Novel Algorithm Utilizing Expanded Donor Criteria for the Allocation of Dual Kidneys in Adults.

PubMed

Johnson, Adam P; Price, Thea P; Lieby, Benjamin; Doria, Cataldo

2016-09-08

BACKGROUND Dual kidney transplantation (DKT) of expanded-criteria donors is a cost-intensive procedure that aims to increase the pool of available deceased organ donors and has demonstrated equivalent outcomes to expanded-criteria single kidney transplantation (eSKT). The objective of this study was to develop an allocation score based on predicted graft survival from historical dual and single kidney donors. MATERIAL AND METHODS We analyzed United Network for Organ Sharing (UNOS) data for 1547 DKT and 26 381 eSKT performed between January 1994 and September 2013. We utilized multivariable Cox regression to identify variables independently associated with graft survival in dual and single kidney transplantations. We then derived a weighted multivariable product score from calculated hazard ratios to model the benefit of transplantation as dual kidneys. RESULTS Of 36 donor variables known at the time of listing, 13 were significantly associated with graft survival. The derived dual allocation score demonstrated good internal validity with strong correlation to improved survival in dual kidney transplants. Donors with scores less than 2.1 transplanted as dual kidneys had a worsened median survival of 594 days (24%, p-value 0.031) and donors with scores greater than 3.9 had improved median survival of 1107 days (71%, p-value 0.002). There were 17 733 eSKT (67%) and 1051 DKT (67%) with scores in between these values and no differences in survival (p-values 0.676 and 0.185). CONCLUSIONS We have derived a dual kidney allocation score (DKAS) with good internal validity. Future prospective studies will be required to demonstrate external validity, but this score may help to standardize organ allocation for dual kidney transplantation.

Dual Kidney Transplantation: Is It Worth It?

PubMed

Snanoudj, Renaud; Timsit, Marc-Olivier; Rabant, Marion; Tinel, Claire; Lazareth, Hélène; Lamhaut, Lionel; Martinez, Frank; Legendre, Christophe

2017-03-01

Use of expanded criteria donor (ECD) kidneys, which are associated with a reduced graft survival rate, has become widely adopted in elderly recipients in an old-to-old allocation system. However, the results are frequently unsatisfactory, and a high proportion of these ECD kidneys are discarded. Dual kidney transplantation (DKT) is an underused way to expand the pool of ECD kidneys and to rapidly transplant elderly patients with satisfactory results because of the transplantation of double the nephronic mass. In this overview, we summarize the results of the main studies on DKT. DKT suffers from a prejudice of heaviness and is considered to be useless by transplant centers that do not perform it. The literature is often biased by the heterogeneity of the criteria leading to a DKT and the common refusal of kidneys that are judged too marginal. In fact, we show that when strictly allocated according to reliable clinical or histological scores, dual and single ECD transplantations yield similar results in terms of patient and graft survival rates despite significant differences in donors' characteristics. DKTs are not associated with a higher proportion of surgical complications, except in some studies showing thrombosis of 1 of the 2 grafts. The benefits of dual transplantation are particularly evident for kidneys coming from most ECDs. There is still a need for more studies to find the best allocation criteria that would permit transplantation to the highest number of patients with similar outcomes in recipients of single and dual ECD kidneys.

Current organ allocation disadvantages kidney alone recipients over combined organ recipients.

PubMed

Martin, Michael S; Hagan, Michael E; Granger, Darla K

2016-03-01

The United Network for Organ Sharing began including the Kidney Donor Profile Index (KDPI) March 26, 2012 and began a new allocation scheme December 1, 2014. Kidney donors from our organ procurement organization from March 2012 to December 2014 were reviewed. The KDPIs of all 919 kidney only transplants were compared with all 102 kidney/extrarenal transplants. The average KDPI for kidney alone allografts was 47 (range 1 to 100) (standard deviation = 25.83) vs 27 for kidney/extrarenal kidneys (range 1 to 82) (standard deviation = 20.16) (P < .001, t test). Multivariate analysis including in- vs out-of-state recipient, donor body mass index, and donation after cardiac death vs brain-dead donor showed significantly lower KDPI for kidney/extrarenal transplants. Kidney/extrarenal organs have decreased graft survival compared with kidneys transplanted alone. In this sample, 21% of lower KDPI kidneys were allocated as kidney/extrarenal organs. This disadvantages those waiting for a kidney alone. Attention to the outcomes of kidneys transplanted with extrarenal organs is needed. Copyright © 2016 Elsevier Inc. All rights reserved.

Global trends and challenges in deceased donor kidney allocation.

PubMed

Wu, Diana A; Watson, Christopher J; Bradley, J Andrew; Johnson, Rachel J; Forsythe, John L; Oniscu, Gabriel C

2017-06-01

Worldwide, the number of patients able to benefit from kidney transplantation is greatly restricted by the severe shortage of deceased donor organs. Allocation of this scarce resource is increasingly challenging and complex. Striking an acceptable balance between efficient use of (utility) and fair access to (equity) the limited supply of donated kidneys raises controversial but important debates at ethical, medical, and social levels. There is no international consensus on the recipient and donor factors that should be considered in the kidney allocation process. There is a general trend toward a reduction in the influence of human leukocyte antigen mismatch and an increase in the importance of other factors shown to affect posttransplant outcomes, such as cold ischemia, duration of dialysis, donor and recipient age, and comorbidity. Increased consideration of equity has led to improved access to transplantation for disadvantaged patient groups. There has been an overall improvement in the transparency and accountability of allocation policies. Novel and contentious approaches in kidney allocation include the use of survival prediction scores as a criterion for accessing the waiting list and at the point of organ offering with matching of predicted graft and recipient survival. This review compares the diverse international approaches to deceased donor kidney allocation and their evolution over the last decade. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Geographic disparity in kidney transplantation under KAS.

PubMed

Zhou, Sheng; Massie, Allan B; Luo, Xun; Ruck, Jessica M; Chow, Eric K H; Bowring, Mary G; Bae, Sunjae; Segev, Dorry L; Gentry, Sommer E

2017-12-12

The Kidney Allocation System fundamentally altered kidney allocation, causing a substantial increase in regional and national sharing that we hypothesized might impact geographic disparities. We measured geographic disparity in deceased donor kidney transplant (DDKT) rate under KAS (6/1/2015-12/1/2016), and compared that with pre-KAS (6/1/2013-12/3/2014). We modeled DSA-level DDKT rates with multilevel Poisson regression, adjusting for allocation factors under KAS. Using the model we calculated a novel, improved metric of geographic disparity: the median incidence rate ratio (MIRR) of transplant rate, a measure of DSA-level variation that accounts for patient casemix and is robust to outlier values. Under KAS, MIRR was 1.75 1.81 1.86 for adults, meaning that similar candidates across different DSAs have a median 1.81-fold difference in DDKT rate. The impact of geography was greater than the impact of factors emphasized by KAS: having an EPTS score ≤20% was associated with a 1.40-fold increase (IRR =  1.35 1.40 1.45 , P < .01) and a three-year dialysis vintage was associated with a 1.57-fold increase (IRR =  1.56 1.57 1.59 , P < .001) in transplant rate. For pediatric candidates, MIRR was even more pronounced, at 1.66 1.92 2.27 . There was no change in geographic disparities with KAS (P = .3). Despite extensive changes to kidney allocation under KAS, geography remains a primary determinant of access to DDKT. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Nephrologists' perspectives on waitlisting and allocation of deceased donor kidneys for transplant.

PubMed

Tong, Allison; Howard, Kirsten; Wong, Germaine; Cass, Alan; Jan, Stephen; Irving, Michelle; Craig, Jonathan C

2011-11-01

Deceased donor kidneys are a scarce resource and there is debate about how to maximize the benefit from each donated kidney while ensuring equity of access to transplants. Allocation of kidneys to waitlisted patients is determined by a computer algorithm, but the decision to waitlist patients or accept the kidneys offered is largely at the discretion of nephrologists. This study aims to elicit nephrologists' perspectives on waitlisting patients for kidney transplant and the allocation of deceased kidneys. We conducted semistructured face-to-face interviews with adult and pediatric nephrologists from 15 Australian nephrology or transplant centers. Transcripts were analyzed for descriptive and analytical themes. 25 nephrologists participated. 5 major themes on waitlisting and deceased donor kidney allocation were identified: patient advocacy (championing their own patients, empowering patients, giving hope, individualizing judgments, patient preferences, and limited autonomy), professional and moral integrity (transparency, avoiding value judgments, and eliminating bias), protecting center reputation (gatekeeping), achieving equity (uniformity, avoiding discrimination, and fairness for specific populations), and maximizing societal benefit (prioritizing best use of kidney, resource implications, favoring social contribution, and improving efficiency of the allocation process). In making individual patient assessments, estimates about outcomes for a patient had to be resolved with whether it was reasonable from a broader societal perspective. Nephrologists expressed their primary responsibility in terms of giving their own patients access to a transplant and upholding professional integrity by maintaining transparency and avoiding value judgments and bias. However, nephrologists perceived an obligation to protect their center's reputation through the selection of "good" patients, and this caused some frustration. Despite having personal preferences for optimizing the balance between societal benefit and equity, nephrologists did not want direct responsibility for ensuring societal benefit in clinical practice. Rather, they placed the onus on policy makers and the community to reconcile such tensions and advocate for societal benefit. Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Stumbling toward equity: the role of government in kidney transplantation.

PubMed

Dooley, L G; Gaston, R S

1998-01-01

In Mortal Peril, Professor Epstein is critical of the current, regulated system for organ donation and suggests that a market for organ tissue would better meet the needs of patients. In this response to Professor Epstein, Professor Laura Dooley and Dr. Robert Gaston pair their skills to attack Professor Epstein's analysis. As they have done on several other occasions, Professors Dooley and Gaston argue that the kidney donation and transplantation arena is fraught with racial inequity, and that Professor Epstein's proposal for a market in kidneys will exacerbate this inequity. The authors maintain that to prevent the poor from being excluded from transplants, the government plays a critical (if imperfect) role in the allocation of these scarce resources. Furthermore, government intervention is acceptable to correct past discrimination because there is scientific evidence that the disproportionate incidence of kidney failure in African Americans is related to the evolutionary pressures of slave trading and slavery. Professors Dooley and Gaston also defend their previous efforts to change the government system of allocation and characterize the government's willingness to adopt their recommendations as an appropriate response to scientific research rather than a governmental susceptibility to lobbying from special interest groups. Finally, the authors criticize Professor Epstein's argument that dialysis is a viable alternative to transplantation because there are significant differences in "quality of life, morbidity and survival." Professors Dooley and Gaston conclude that government intervention is necessary for maintaining the equity in kidney transplantation that a market system would not.

Optimizing utilization of kidneys from deceased donors over 60 years: five-year outcomes after implementation of a combined clinical and histological allocation algorithm.

PubMed

Pierobon, Elisa Sefora; Sefora, Pierobon Elisa; Sandrini, Silvio; Silvio, Sandrini; De Fazio, Nicola; Nicola, De Fazio; Rossini, Giuseppe; Giuseppe, Rossini; Fontana, Iris; Iris, Fontana; Boschiero, Luigino; Luigino, Boschiero; Gropuzzo, Maria; Maria, Gropuzzo; Gotti, Eliana; Eliana, Gotti; Donati, Donato; Donato, Donati; Minetti, Enrico; Enrico, Minetti; Gandolfo, Maria Teresa; Teresa, Gandolfo Maria; Brunello, Anna; Anna, Brunello; Libetta, Carmelo; Carmelo, Libetta; Secchi, Antonio; Antonio, Secchi; Chiaramonte, Stefano; Stefano, Chiaramonte; Rigotti, Paolo; Paolo, Rigotti

2013-08-01

This 5 year observational multicentre study conducted in the Nord Italian Transplant programme area evaluated outcomes in patients receiving kidneys from donors over 60 years allocated according to a combined clinical and histological algorithm. Low-risk donors 60-69 years without risk factors were allocated to single kidney transplant (LR-SKT) based on clinical criteria. Biopsy was performed in donors over 70 years or 60-69 years with risk factors, allocated to Single (HR-SKT) or Dual kidney transplant (HR-DKT) according to the severity of histological damage. Forty HR-DKTs, 41 HR-SKTs and 234 LR-SKTs were evaluated. Baseline differences generally reflected stratification and allocation criteria. Patient and graft (death censored) survival were 90% and 92% for HR-DKT, 85% and 89% for HR-SKT, 88% and 87% for LR-SKT. The algorithm appeared user-friendly in daily practice and was safe and efficient, as demonstrated by satisfactory outcomes in all groups at 5 years. Clinical criteria performed well in low-risk donors. The excellent outcomes observed in DKTs call for fine-tuning of cut-off scores for allocation to DKT or SKT in high-risk patients. © 2013 Steunstichting ESOT. Published by John Wiley & Sons Ltd.

Transplantation of A2 and A2B kidneys from deceased donors into B waiting list candidates increases their transplantation rate.

PubMed

Bryan, Christopher F; Nelson, Paul W; Shield, Charles F; Ross, Gilbert; Warady, Bradley; Murillo, Daniel; Winklhofer, Franz T

2004-01-01

Transplant centers in the Midwest Transplant Network began transplanting kidneys from A2 or A2B donors into blood group B and O patients in 1986. Since 1991, an OPTN/UNOS variance has permitted us to allocate these kidneys preferentially into B and O waiting list patients. With more than 10 years of experience we have noted the following: 1. Thirty-one percent more blood group B patients were transplanted by allocating them A2 or A2B kidneys from our deceased donors. 2. Ten-year graft survival for B recipients of an A2 or A2B kidney (72%) was equivalent to that for B recipients of a B kidney (69%). 3. Type B recipients of simultaneous pancreas-kidney transplants (n=4) also did well with A2 or A2B organs. 4. Non-A recipients were transplanted only when their anti-A IgG titer history was consistently low (< or =4). 5. Most (90%) blood group B patients had a low anti-A IgG titer history; whereas, only one-third of blood group O patients had a low titer history. 6. Neither ethnicity nor HLA class I sensitization level influenced the anti-A IgG titer history. 7. In an OPO with mostly (87%) white donors, nearly 20% of blood group A donors were A2. 8. Waiting time until transplantation was lower for B patients who received an A2 or A2B kidney than for those who received a B or O kidney. 9. Our OPO blood group B waiting list was reduced from 25 low PRA (<40%) B candidates in 1994 to 4 in July, 2004. 10. Blood group A candidates received 6.4% fewer transplants with our A2/A2B--> B allocation algorithm. 11. Minority patients were transplanted at the same rate when using the A2/A2B--> B allocation algorithm as when using the standard UNOS algorithm for allocating B and O kidneys--> B patients.

[Analysis of contractual incentives for kidney transplants in Brazil using the principal-agent model].

PubMed

Costa, Cassia Kely Favoretto; Balbinotto, Giácomo; Sampaio, Luciano Menezes Bezerra

2016-09-12

The aim of this article was to analyze contractual incentives for kidney transplants in Brazil based on the principal-agent model. The approach assumes that the Brazilian Ministry of Health is the principal and the public hospitals accredited by the National Transplant System are the agent. The Ministry of Health's welfare depends on measures taken by hospitals in kidney uptake. Hospitals allocate administrative, financial, and management efforts to conduct measures in kidney donation, removal, uptake, and transplantation. Hospitals may choose the levels of effort that are consistent with the payments and incentives received in relation to transplantation costs. The solution to this type of problem lies in structuring an optimal incentives contract, which requires aligning the interests of both parties involved in the transplantation system.

Access to kidney transplantation in European adults aged 75-84 years and related outcomes: an analysis of the European Renal Association-European Dialysis and Transplant Association Registry.

PubMed

Pippias, Maria; Stel, Vianda S; Kramer, Anneke; Abad Diez, Jose M; Aresté-Fosalba, Nuria; Ayav, Carole; Buturovic, Jadranka; Caskey, Fergus J; Collart, Frederic; Couchoud, Cécile; De Meester, Johan; Heaf, James G; Helanterä, Ilkka; Hemmelder, Marc H; Kostopoulou, Myrto; Noordzij, Marlies; Pascual, Julio; Palsson, Runolfur; Reisaeter, Anna Varberg; Traynor, Jamie P; Massy, Ziad; Jager, Kitty J

2018-05-01

To what extent access to, and allocation of kidney transplants and survival outcomes in patients aged ≥75 years have changed over time in Europe is unclear. We included patients aged ≥75-84 years (termed older adults) receiving renal replacement therapy in thirteen European countries between 2005 and 2014. Country differences and time trends in access to, and allocation of kidney transplants were examined. Survival outcomes were determined by Cox regression analyses. Between 2005 and 2014, 1392 older adult patients received 1406 transplants. Access to kidney transplantation varied from ~0% (Slovenia, Greece and Denmark) to ~4% (Norway and various Spanish regions) of all older adult dialysis patients, and overall increased from 0.3% (2005) to 0.9% (2014). Allocation of kidney transplants to older adults overall increased from 0.8% (2005) to 3.2% (2014). Seven-year unadjusted patient and graft survival probabilities were 49.1% (95% confidence interval, 95% CI: 43.6; 54.4) and 41.7% (95% CI: 36.5; 46.8), respectively, with a temporal trend towards improved survival outcomes. In conclusion, in the European dialysis population aged ≥75-84 years access to kidney transplantation is low, and allocation of kidney transplants remains a rare event. Though both are increasing with time and vary considerably between countries. The trend towards improved survival outcomes is encouraging. This information can aid informed decision-making regarding treatment options. © 2018 Steunstichting ESOT.

Decision tables and rule engines in organ allocation systems for optimal transparency and flexibility.

PubMed

Schaafsma, Murk; van der Deijl, Wilfred; Smits, Jacqueline M; Rahmel, Axel O; de Vries Robbé, Pieter F; Hoitsma, Andries J

2011-05-01

Organ allocation systems have become complex and difficult to comprehend. We introduced decision tables to specify the rules of allocation systems for different organs. A rule engine with decision tables as input was tested for the Kidney Allocation System (ETKAS). We compared this rule engine with the currently used ETKAS by running 11,000 historical match runs and by running the rule engine in parallel with the ETKAS on our allocation system. Decision tables were easy to implement and successful in verifying correctness, completeness, and consistency. The outcomes of the 11,000 historical matches in the rule engine and the ETKAS were exactly the same. Running the rule engine simultaneously in parallel and in real time with the ETKAS also produced no differences. Specifying organ allocation rules in decision tables is already a great step forward in enhancing the clarity of the systems. Yet, using these tables as rule engine input for matches optimizes the flexibility, simplicity and clarity of the whole process, from specification to the performed matches, and in addition this new method allows well controlled simulations. © 2011 The Authors. Transplant International © 2011 European Society for Organ Transplantation.

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.

Swaps and Chains and Vouchers, Oh My!: Evaluating How Saving More Lives Impacts the Equitable Allocation of Live Donor Kidneys.

PubMed

Tenenbaum, Evelyn M

2018-03-01

Live kidney donation involves a delicate balance between saving the most lives possible and maintaining a transplant system that is fair to the many thousands of patients on the transplant waiting list. Federal law and regulations require that kidney allocation be equitable, but the pressure to save patients subject to ever-lengthening waiting times for a transplant has been swinging the balance toward optimizing utility at the expense of justice. This article traces the progression of innovations created to make optimum use of a patient's own live donors. It starts with the simplest - direct donation by family members - and ends with voucher donations, a very recent and unique innovation because the donor can donate 20 or more years before the intended recipient is expected to need a kidney. In return for the donation, the intended recipient receives a voucher that can be redeemed for a live kidney when it is needed. Other innovations that are discussed include kidney exchanges and list paired donation, which are used to facilitate donor swaps when donor/recipient pairs have incompatible blood types. The discussion of each new innovation shows how the equity issues build on each other and how, with each new innovation, it becomes progressively harder to find an acceptable balance between utility and justice. The article culminates with an analysis of two recent allocation methods that have the potential to save many additional lives, but also affirmatively harm some patients on the deceased donor waiting list by increasing their waiting time for a life-saving kidney. The article concludes that saving additional lives does not justify harming patients on the waiting list unless that harm can be minimized. It also proposes solutions to minimize the harm so these new innovations can equitably perform their intended function of stimulating additional transplants and extending the lives of many transplant patients.

Addressing the shortage of kidneys for transplantation: purchase and allocation through chain auctions.

PubMed

Rosen, Lara; Vining, Aidan R; Weimer, David L

2011-08-01

Transplantation is generally the treatment of choice for those suffering from kidney failure. Not only does transplantation offer improved quality of life and increased longevity relative to dialysis, it also reduces end-stage renal disease program expenditures, providing savings to Medicare. Unfortunately, the waiting list for kidney transplants is long, growing, and unlikely to be substantially reduced by increases in the recovery of cadaveric kidneys. Another approach is to obtain more kidneys through payment to living "donors," or vendors. Such direct commodification, in which a price is placed on kidneys, has generally been opposed by medical ethicists. Much of the ethical debate, however, has been in terms of commodification through market exchange. Recognizing that there are different ethical concerns associated with the purchase of kidneys and their allocation, it is possible to design a variety of institutional arrangements for the commodification of kidneys that pose different sets of ethical concerns. We specify three such alternatives in detail sufficient to allow an assessment of their likely consequences and we compare these alternatives to current policy in terms of the desirable goals of promoting human dignity, equity, efficiency, and fiscal advantage. This policy analysis leads us to recommend that kidneys be purchased at administered prices by a nonprofit organization and allocated to the transplant centers that can organize the longest chains of transplants involving willing-but-incompatible donor-patient dyads.

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.

The Evolution of Organ Allocation for Liver Transplantation: Tackling Geographic Disparity Through Broader Sharing.

PubMed

Axelrod, David A; Vagefi, Parsia A; Roberts, John P

2015-08-01

The liver transplant allocation system has evolved to a ranking system of “sickest-first” system based on objective criteria. Yet, organs continue to be distributed first within OPOs and regions that are largely based on historical practice patterns related to kidney transplantation and were never designed to minimize waitlist death or equalize opportunity for liver transplant. The current proposal is a move to enhance survival though the application of modern mathematical techniques to optimize liver distribution. Like MELDbased allocation, it will never be perfect and should be continually evaluated and revised. However, the disparity in access, which favors those residing in or able to travel to privileged areas, to the detriment of the patients dying on the list in underserved areas, is simply not defensible in 2015.

Design of a regulated system of compensation for living kidney donors.

PubMed

Matas, Arthur J

2008-01-01

The pros and cons of a regulated system of financial incentives for living donors are being actively debated. To date, a detailed proposal on how such a system could work has not been developed. Herein, the specifics of a potential model, using the infrastructure already in place for deceased donor evaluation and allocation, are outlined.

Deceased donor renal transplantation from older donors to increase the donor pool.

PubMed

Kute, Vivek B; Trivedi, Hargovind L; Vanikar, Aruna V; Shah, Pankaj R; Gumber, Manoj R; Patel, Himanshu V; Modi, Pranjal R; Shah, Veena R

2012-09-01

Use of kidneys from donors aged 70 years and older is controversial. Organ shortage has led many transplant centers to accept kidneys from old, suboptimal deceased donors and make increasing use of old-for-old allocation systems. We describe our institutional experience with outcomes from transplanting deceased-donor kidneys from older donors (=70 years). 20 deceased donor renal transplants (DDRTx) were performed at our center using grafts from deceased donors 70 years and older between June 2004 and September 2011. Kidneys were allocated to dual or single grafting according to pre-transplant biopsy. Mean age of recipients was 47.60 ± 11.38 years, 13 of whom were males. Mean donor age was 76.49 ± 4.9 years; 10 of whom were males. The most common cause of donor death was cerebrovascular/road traffic accidents. Mean dialysis duration pre-transplantation was 19.5 ± 6.5 months. Mean HLA (Human Leukocyte Antigens) match was 1 ± 0.8. Most common recipient diseases leading to ESRD were chronic glomerulonephritis (25%), diabetes (20%), and hypertension (20%). Post-transplant immunosuppression consisted of a calcineurin inhibitor-based regimen. Over a mean follow-up of 2.8 ± 1.7 years, patient and graft survival rates were 75% (n = 15) and 80% ( n = 16), respectively, with a mean serum creatinine of 1.78 ± 0.56 mg/dl; 20% of the patients had biopsy-proven acute rejection episodes. A total of 25% (n = 5) patients died, mainly due to infections. DDRTx from older donors achieves acceptable graft function with patient/graft survival, provided that organs are allocated to dual or single grafting according to pre-transplant biopsy. These findings encourage the use of this approach even in low-income countries.

Use of the ‘Accountability for Reasonableness’ Approach to Improve Fairness in Accessing Dialysis in a Middle-Income Country

PubMed Central

Maree, Jonathan David; Chirehwa, Maxwell T.; Benatar, Solomon R.

2016-01-01

Universal access to renal replacement therapy is beyond the economic capability of most low and middle-income countries due to large patient numbers and the high recurrent cost of treating end stage kidney disease. In countries where limited access is available, no systems exist that allow for optimal use of the scarce dialysis facilities. We previously reported that using national guidelines to select patients for renal replacement therapy resulted in biased allocation. We reengineered selection guidelines using the ‘Accountability for Reasonableness’ (procedural fairness) framework in collaboration with relevant stakeholders, applying these in a novel way to categorize and prioritize patients in a unique hierarchical fashion. The guidelines were primarily premised on patients being transplantable. We examined whether the revised guidelines enhanced fairness of dialysis resource allocation. This is a descriptive study of 1101 end stage kidney failure patients presenting to a tertiary renal unit in a middle-income country, evaluated for dialysis treatment over a seven-year period. The Assessment Committee used the accountability for reasonableness-based guidelines to allocate patients to one of three assessment groups. Category 1 patients were guaranteed renal replacement therapy, Category 3 patients were palliated, and Category 2 were offered treatment if resources allowed. Only 25.2% of all end stage kidney disease patients assessed were accepted for renal replacement treatment. The majority of patients (48%) were allocated to Category 2. Of 134 Category 1 patients, 98% were accepted for treatment while 438 (99.5%) Category 3 patients were excluded. Compared with those palliated, patients accepted for dialysis treatment were almost 10 years younger, employed, married with children and not diabetic. Compared with our previous selection process our current method of priority setting based on procedural fairness arguably resulted in more equitable allocation of treatment but, more importantly, it is a model that is morally, legally and ethically more defensible. PMID:27701466

OPTN/SRTR 2014 ANNUAL DATA REPORT

PubMed Central

Hart, A.; Smith, J. M.; Skeans, M. A.; Gustafson, S. K.; Stewart, D. E.; Cherikh, W. S.; Wainright, J. L.; Boyle, G.; Snyder, J. J.; Kasiske, B. L.; Israni, A. K.

2017-01-01

Kidney transplant provides significant survival, cost, and quality-of-life benefits over dialysis in patients with end-stage kidney disease, but the number of kidney transplant candidates on the waiting list continues to grow annually. By the end of 2014, nearly 100,000 adult candidates and 1500 pediatric candidates were waiting for kidney transplant. Not surprisingly, waiting times also continued to increase, along with the number of adult candidates removed from the list due to death or deteriorating medical condition. Death censored graft survival has increased after both living and deceased donor transplants over the past decade in adult recipients. The majority of the trends seen over the past 5 years continued in 2014. However, the new allocation system was implemented in late 2014, providing an opportunity to assess changes in these trends in the coming years. PMID:26755262

Patient and health professional preferences for organ allocation and procurement, end-of-life care and organization of care for patients with chronic kidney disease using a discrete choice experiment.

PubMed

Davison, Sara N; Kromm, Seija K; Currie, Gillian R

2010-07-01

Clinical practice, policy and research, and the ethical bases upon which they are founded, should be systematically and transparently informed by both patient and professional values. A discrete choice experiment was utilized to understand and quantify the preferences of 351 Canadian patients and healthcare providers in relation to ethically challenging aspects of the management of chronic kidney disease (CKD): procurement and allocation of organs for transplantation, end-of-life care discussions and decision making and the identities of those providing primary care. Patients and health professionals had clear preferences for detailed prognostic information, early advance care planning, shared end-of-life decision making, coordinated models of care that enhance interaction and communication between primary and tertiary care and a more utilitarian approach of best match over first come, first served for allocating deceased donor kidneys. These data also suggest that the innovative strategies of non-directed anonymous donation and paired kidney exchange that are slowly being implemented internationally will be acceptable to both patients and healthcare providers. Current models of CKD care do not consistently reflect the preferences or priorities of either health professionals or patients.

Living-Donor Kidney Transplantation: Reducing Financial Barriers to Live Kidney Donation--Recommendations from a Consensus Conference.

PubMed

Tushla, Lara; Rudow, Dianne LaPointe; Milton, Jennifer; Rodrigue, James R; Schold, Jesse D; Hays, Rebecca

2015-09-04

Live-donor kidney transplantation (LDKT) is the best treatment for eligible people with late-stage kidney disease. Despite this, living kidney donation rates have declined in the United States in recent years. A potential source of this decline is the financial impact on potential and actual living kidney donors (LKDs). Recent evidence indicates that the economic climate may be associated with the decline in LDKT and that there are nontrivial financial ramifications for some LKDs. In June 2014, the American Society of Transplantation's Live Donor Community of Practice convened a Consensus Conference on Best Practices in Live Kidney Donation. The conference included transplant professionals, patients, and other key stakeholders (with the financial support of 10 other organizations) and sought to identify best practices, knowledge gaps, and opportunities pertaining to living kidney donation. This workgroup was tasked with exploring systemic and financial barriers to living kidney donation. The workgroup reviewed literature that assessed the financial effect of living kidney donation, analyzed employment and insurance factors, discussed international models for addressing direct and indirect costs faced by LKDs, and summarized current available resources. The workgroup developed the following series of recommendations to reduce financial and systemic barriers and achieve financial neutrality for LKDs: (1) allocate resources for standardized reimbursement of LKDs' lost wages and incidental costs; (2) pass legislation to offer employment and insurability protections to LKDs; (3) create an LKD financial toolkit to provide standardized, vetted education to donors and providers about options to maximize donor coverage and minimize financial effect within the current climate; and (4) promote further research to identify systemic barriers to living donation and LDKT to ensure the creation of mitigation strategies. Copyright © 2015 by the American Society of Nephrology.

Living-Donor Kidney Transplantation: Reducing Financial Barriers to Live Kidney Donation—Recommendations from a Consensus Conference

PubMed Central

Rudow, Dianne LaPointe; Milton, Jennifer; Rodrigue, James R.; Schold, Jesse D.; Hays, Rebecca

2015-01-01

Live-donor kidney transplantation (LDKT) is the best treatment for eligible people with late-stage kidney disease. Despite this, living kidney donation rates have declined in the United States in recent years. A potential source of this decline is the financial impact on potential and actual living kidney donors (LKDs). Recent evidence indicates that the economic climate may be associated with the decline in LDKT and that there are nontrivial financial ramifications for some LKDs. In June 2014, the American Society of Transplantation’s Live Donor Community of Practice convened a Consensus Conference on Best Practices in Live Kidney Donation. The conference included transplant professionals, patients, and other key stakeholders (with the financial support of 10 other organizations) and sought to identify best practices, knowledge gaps, and opportunities pertaining to living kidney donation. This workgroup was tasked with exploring systemic and financial barriers to living kidney donation. The workgroup reviewed literature that assessed the financial effect of living kidney donation, analyzed employment and insurance factors, discussed international models for addressing direct and indirect costs faced by LKDs, and summarized current available resources. The workgroup developed the following series of recommendations to reduce financial and systemic barriers and achieve financial neutrality for LKDs: (1) allocate resources for standardized reimbursement of LKDs' lost wages and incidental costs; (2) pass legislation to offer employment and insurability protections to LKDs; (3) create an LKD financial toolkit to provide standardized, vetted education to donors and providers about options to maximize donor coverage and minimize financial effect within the current climate; and (4) promote further research to identify systemic barriers to living donation and LDKT to ensure the creation of mitigation strategies. PMID:26002904

OPTN/SRTR 2015 Annual Data Report: Kidney

PubMed Central

Hart, A.; Smith, J. M.; Skeans, M. A.; Gustafson, S. K.; Stewart, D. E.; Cherikh, W. S.; Wainright, J. L.; Kucheryavaya, A.; Woodbury, M.; Snyder, J. J.; Kasiske, B. L.; Israni, A. K.

2017-01-01

The first full year of data after implementation of the new kidney allocation system reveals an increase in deceased donor kidney transplants among black candidates and those with calculated panel-reactive antibodies 98%–100%, but a decrease among candidates aged 65 years or older. Data from 2015 also demonstrate ongoing positive trends in graft and patient survival for both deceased and living donor kidney transplants, but the challenges of a limited supply of kidneys in the setting of increasing demand remain evident. While the total number of patients on the waiting list decreased for the first time in a decade, this was due to a combination of a decrease in the number of candidates added to the list and an increase in the number of candidates removed from the list due to deteriorating medical condition, as well as an increase in total transplants. Deaths on the waiting list remained at, but this was likely because of an increasing trend toward removing inactive candidates too sick to undergo transplant. PMID:28052609

The Effect of IV Amino Acid Supplementation on Mortality in ICU Patients May Be Dependent on Kidney Function: Post Hoc Subgroup Analyses of a Multicenter Randomized Trial.

PubMed

Zhu, Ran; Allingstrup, Matilde J; Perner, Anders; Doig, Gordon S

2018-05-15

We investigated whether preexisting kidney function determines if ICU patients may benefit from increased (2.0 g/kg/d) protein intake. Post hoc, hypothesis-generating, subgroup analysis of a multicenter, phase 2, randomized clinical trial. All analyses were conducted by intention to treat and maintained group allocation. Ninety-day mortality was the primary outcome. ICUs of 16 hospitals throughout Australia and New Zealand. Adult critically ill patients expected to remain in the study ICU for longer than 2 days. Random allocation to receive a daily supplement of up to 100 g of IV amino acids to achieve a total protein intake of 2.0 g/kg/d or standard nutrition care. A total of 474 patients were randomized: 235 to standard care and 239 to IV amino acid supplementation. There was a statistically significant interaction between baseline kidney function and supplementation with study amino acids (p value for interaction = 0.026). Within the subgroup of patients with normal kidney function at randomization, patients who were allocated to receive the study amino acid supplement were less likely to die before study day 90 (covariate-adjusted risk difference, -7.9%; 95% CI, -15.1 to -0.7; p = 0.034). Furthermore, amino acid supplementation significantly increased estimated glomerular filtration rate in these patients (repeated-measures treatment × time interaction p = 0.009). Within the subgroup of patients with baseline kidney dysfunction and/or risk of progression of acute kidney injury, a significant effect of the study intervention on mortality was not found (covariate-adjusted risk difference, -0.6%; 95% CI, -16.2 to 15.2; p = 0.95). In this post hoc, hypothesis-generating, subgroup analysis, we observed reduced mortality and improved estimated glomerular filtration rate in ICU patients with normal kidney function who were randomly allocated to receive increased protein intake (up to 2.0 g/kg/d). We strongly recommend confirmation of these results in trials with low risk of bias before this treatment is recommended for routine care.

[Organ allocation system: between efficiency and equity].

PubMed

Antoine, Corinne

2007-02-15

Despite considerable efforts to promote organ donation and increase the amount of organ retrieval, demand for grafts is increasing and remains much higher then availability. This short supply is noticeable for all organ transplantation whether for heart, lungs, liver or pancreas but mainly for kidneys. The objective of graft allocation and attribution rules is to insure an allocation as fair as possible, to find the best recipient, to take into account the emergency of the need for grafting or the access difficulty for certain patients, and to seek optimal graft usage. These rules are based on the setting up of priority categories for patients whose lives are threatened on a very short-term basis or for those having difficult access to transplantation. This implies the issue of seeking the balance between an allocation as fair as possible and technical constraints associated with organ retrieval, transportation and graft quality preservation.

Harnessing Scientific and Technological Advances to Improve Equity in Kidney Allocation Policies.

PubMed

Tambur, A R; Audry, B; Antoine, C; Suberbielle, C; Glotz, D; Jacquelinet, C

2017-12-01

We reported that current assignment of HLA-DQ is a barrier to organ allocation. Here we simulated the impact of incorporating HLA-DQ antigens and antibodies as A/B and αβ allelic variants, respectively, on calculated panel reactive antibody (cPRA) and probability of finding potential compatible donors (PCD). A cohort of 1224 donors and 2075 sensitized candidates was analyzed using HLA-DQαβ allelic (study) versus serologic (current practice) nomenclature. A significant (p < 10 -4 ) decrease in cPRA was observed with higher impact for male versus female, and first transplant versus retransplant (p < 10 -4 ), affecting mostly patients with moderate cPRA (30-80%). Consequently, the number of patients qualifying for 100% cPRA points according to the United Network for Organ Sharing-Kidney Allocation System decreased by 37%. More critically, by using allelic versus serologic nomenclature for HLA-DQ, the number of PCDs for all patients was increased, with male and first-transplant patients showing a higher expansion compared with female and retransplants. Patients of blood group O showed the highest benefit. The goal of reporting unacceptable antigens is to improve accuracy of virtual crossmatching and increase the likelihood of finding immunologically compatible donors. Our simulation provides strong support for the need to re-evaluate the use of allele typing and how HLA-DQ antigens and antibodies are incorporated into allocation policies to ensure equity. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

A New UK 2006 National Kidney Allocation Scheme for deceased heart-beating donor kidneys.

PubMed

Johnson, Rachel J; Fuggle, Susan V; Mumford, Lisa; Bradley, J Andrew; Forsythe, John L R; Rudge, Chris J

2010-02-27

In 2004, it was agreed that a new allocation scheme for kidneys from deceased heart-beating donors was required in the United Kingdom to address observed inequities in access to transplant. The 2006 National Kidney Allocation Scheme (2006 NKAS) was developed to meet agreed objectives and preparatory work included a review of the criteria for human leukocyte antigen (HLA) matching and simulation evidence about the effectiveness of alternative schemes. ALGORITHM FOR 2006 NKAS: The 2006 NKAS gives absolute priority to all 000 HLA-A, -B, -DR-mismatched patients and well-matched pediatric patients (<18 years), and then a points score defines priorities for allocation with waiting time being most influential. Points for age and HLA mismatch are linked in a novel approach to ensure well-matched transplants for younger patients while recognizing that HLA matching is less important for older patients as retransplantation is less likely to be required. To improve equity for difficult to match patients, rare HLA specificities were defaulted to more common, related specificities. IMPACT OF 2006 NKAS: After 3 years, the scheme is already making good progress in achieving its objectives, with overall results similar to those observed in the simulations. There has been a significant benefit for patients waiting more than 5 years for transplant. A number of other advantages of the scheme are also apparent with equity of access improving in many respects, including the achievement of equity of access to transplant for HLA-DR homozygous patients, but geographical inequity of access will take a number of years to address fully.

A Cost Analysis of Kidney Replacement Therapy Options in Palestine

PubMed Central

Jabr, Samer; Al-Khatib, Abdallah; Forgione, Dana; Hartmann, Michael; Kisa, Adnan

2015-01-01

This study provides a cost analysis of kidney replacement therapy options in Palestine. It informs evidence-based resource allocation decisions for government-funded kidney disease services where transplant donors are limited, and some of the common modalities, i.e., peritoneal dialysis (PD) and home hemodialysis (HD), are not widely available due to shortages of qualified staff, specialists, and centers to follow the patient cases, provide training, make home visits, or provide educational programs for patients. The average cost of kidney transplant was US$16 277 for the first year; the estimated cost of HD per patient averaged US$16 085 per year—nearly as much as a transplant. Consistent with prior literature and experience, while live, related kidney donors are scarce, we found that kidney transplant was more adequate and less expensive than HD. These results have direct resource allocation implications for government-funded kidney disease services under Palestinian Ministry of Health. Our findings strongly suggest that investing in sufficient qualified staff, equipment, and clinical infrastructure to replace HD services with transplantation whenever medically indicated and suitable kidney donors are available, as well as deploying PD programs and Home HD programs, will result in major overall cost savings. Our results provide a better understanding of the costs of kidney disease and will help to inform Ministry of Health and related policy makers as they develop short- and long-term strategies for the population, in terms of both cost savings and enhanced quality of life. PMID:25765018

A cost analysis of kidney replacement therapy options in Palestine.

PubMed

Younis, Mustafa; Jabr, Samer; Al-Khatib, Abdallah; Forgione, Dana; Hartmann, Michael; Kisa, Adnan

2015-01-01

This study provides a cost analysis of kidney replacement therapy options in Palestine. It informs evidence-based resource allocation decisions for government-funded kidney disease services where transplant donors are limited, and some of the common modalities, i.e., peritoneal dialysis (PD) and home hemodialysis (HD), are not widely available due to shortages of qualified staff, specialists, and centers to follow the patient cases, provide training, make home visits, or provide educational programs for patients. The average cost of kidney transplant was US$16,277 for the first year; the estimated cost of HD per patient averaged US$16,085 per year--nearly as much as a transplant. Consistent with prior literature and experience, while live, related kidney donors are scarce, we found that kidney transplant was more adequate and less expensive than HD. These results have direct resource allocation implications for government-funded kidney disease services under Palestinian Ministry of Health. Our findings strongly suggest that investing in sufficient qualified staff, equipment, and clinical infrastructure to replace HD services with transplantation whenever medically indicated and suitable kidney donors are available, as well as deploying PD programs and Home HD programs, will result in major overall cost savings. Our results provide a better understanding of the costs of kidney disease and will help to inform Ministry of Health and related policy makers as they develop short- and long-term strategies for the population, in terms of both cost savings and enhanced quality of life. © The Author(s) 2015.

Decision Making by Young Transplant Surgeons Regarding Expanded-Criteria Donors With Acute Kidney Injury or Allocation Failure.

PubMed

Jung, D; Park, S; Kim, S H; Eom, M; Kim, J S; Yang, J W; Han, B G; Choi, S O

2016-04-01

The utilization of expanded-criteria donors (ECDs) has increased to overcome donor shortages. Unfortunately, the discard rate has also increased, especially in ECDs with acute kidney injury (AKI). We evaluated the outcomes of kidney transplantation in ECDs and standard-criteria donors (SCDs) with and without AKI. We reviewed the medical records of patients who underwent kidney transplantation. We used the AKI definition published by the Kidney Disease: Improving Global Outcomes group and reviewed the demographic characteristics of donors and recipients. We analyzed transplantation outcomes. Twenty-seven patients underwent kidney transplantation from ECDs with AKI (n = 6) or without AKI (n = 5) and SCDs with AKI (n = 6) or without AKI (n = 10). Initial creatinine and estimated glomerular filtration rate (eGFR) were not significantly different between the groups. The incidence of delayed graft function was highest in ECDs with AKI (n = 3; 36.4%), but this was not a significantly difference. There was no difference in the last creatinine and eGFR in ECDs with AKI (1.32 mg/dL, 58.7 mL/min/1.73 m(2)), ECDs without AKI (1.67 mg/dL, 44.2 mL/min/1.73 m(2)), SCDs with AKI (0.94 mg/dL, 81.5 mL/min/1.73 m(2)) and SCDs without AKI (0.97 mg/dL, 81.8 mL/min/1.73 m(2)). As the donor pool is extended to ECDs, young transplant surgeons may increasingly face decisions regarding ECDs with AKI or allocation failure. There is no consensus regarding discard criteria. However, if the donor showed initially normal creatinine levels or if dual-kidney transplantation can be performed, young transplant surgeons should not hesitate to use ECDs with AKI or allocation failure. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical results of an organ procurement organization effort to increase utilization of donors after cardiac death.

PubMed

Whiting, James F; Delmonico, Francis; Morrissey, Paul; Basadonna, Giacomo; Johnson, Scott; Lewis, W David; Rohrer, Richard; O'Connor, Kevin; Bradley, James; Lovewell, Tammy D; Lipkowitz, George

2006-05-27

To stimulate organ donation, an organ procurement organization (OPO)-wide effort was undertaken to increase donors after cardiac death (DCD) over a 5-year period. This included commonality of protocols, pulsatile perfusion of kidneys, centralization of data and a regional allocation variance designed to minimize cold ischemia times and encourage adoption of DCD protocols at transplant centers. In one OPO, eight centers initiated DCD programs in 11 hospitals. A total of 52 DCD donors were procured, increasing from four in 1999 to 21 in 2003. Eleven donors had care withdrawn in the operating room, whereas 41 had care withdrawn in the ICU. In all, 91 patients received renal transplants from these 52 donors (12 kidneys discarded, one double transplant), whereas 5 patients received liver transplants. One-, two-, and three-year kidney graft survival rates were 90%, 90%, and 82%, respectively. Fifty-five percent of patients needed at least one session of hemodialysis postoperatively. Mean recipient hospital length of stay was 11.1+/-6 days. Mean creatinine levels at 3, 6, 12, and 24 months were 1.65, 1.40, 1.41, and 1.40, respectively. DCD donors can be an important source of donor organs and provide excellent overall outcomes. Regional cooperation and a prospectively considered allocation and distribution system are important considerations in stimulating DCD programs.

Setting Research Priorities for Kidney Cancer.

PubMed

Jones, Jennifer M; Bhatt, Jaimin; Avery, Jonathan; Laupacis, Andreas; Cowan, Katherine; Basappa, Naveen S; Basiuk, Joan; Canil, Christina; Al-Asaaed, Sohaib; Heng, Daniel Y C; Wood, Lori; Stacey, Dawn; Kollmannsberger, Christian; Jewett, Michael A S

2017-12-01

Defining disease-specific research priorities in cancer can facilitate better allocation of limited resources. Involving patients and caregivers as well as expert clinicians in this process is of value. We undertook this approach for kidney cancer as an example. The Kidney Cancer Research Network of Canada sponsored a collaborative consensus-based priority-setting partnership that identified ten research priorities in the management of kidney cancer. These are discussed in the context of current initiatives and gaps in knowledge. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Impact of cold ischemia time on the outcomes of kidneys with Kidney Donor Profile Index ≥85%: mate kidney analysis - a retrospective study.

PubMed

Sampaio, Marcelo S; Chopra, Bhavna; Tang, Amy; Sureshkumar, Kalathil K

2018-07-01

The new kidney allocation system recommends local and regional sharing of deceased donor kidneys (DDK) with 86-100% Kidney Donor Profile Index (KDPI) to minimize discard. Regional sharing can increase cold ischemia time (CIT) which may negatively impact transplant outcomes. Using a same donor mate kidney model, we aimed to define a CIT that should be targeted to optimize outcomes. Using Organ Procurement and Transplant Network/United Network for Organ Sharing database, we identified recipients of DDK from 2000 to 2013 with ≥85% KDPI. From this cohort, three groups of mate kidney recipients were identified based on CIT: group 1 (≥24 vs. ≥12 to <24 h), group 2 (≥24 vs. <12 h), and group 3 (≥12 to <24 vs. <12 h). Adjusted delayed graft function (DGF), and graft and patient survivals were compared for mate kidneys. DGF risk was significantly lower for patients with CIT <12 vs. ≥24 h in group 2 (adjusted OR: 0.25, 95% CI: 0.12-0.57, P < 0.001) while trending lower for CIT ≥12 to <24 vs. ≥24 h in group 1 (adjusted OR: 0.78, 95% CI: 0.59-1.03, P = 0.08) and CIT <12 vs. ≥12 to <24 h in group 3 (adjusted OR: 0.74, 95% CI: 0.55-1.0, P = 0.05). Adjusted graft and patient survivals were similar between mate kidneys in all groups. Minimizing CIT improves outcomes with regional sharing of marginal kidneys. © 2018 Steunstichting ESOT.

Allocating scarce medical resources to the overweight.

PubMed

Furnham, Adrian; Loganathan, Niroosha; McClelland, Alastair

2010-01-01

A programmatic research effort investigated how lay people weigh information on hypothetical patients when making decisions regarding the allocation of scarce medical resources. This study is partly replicative and partly innovative, and looks particularly at whether overweight patients would be discriminated against in allocating resources. This study aims to determine the importance given to specific patient characteristics when lay participants are asked to allocate scarce medical resources. In all, 156 British adults (82 males, 73 females), aged 19 to 84 years, took part. There were few students. Participants completed a questionnaire requiring them to rank 16 hypothetical patients for access to a kidney dialysis machine.The demographic information presented regarding each hypothetical patient differed on four dimensions: gender, weight, mental health, and religiousness. There were significant main effects for gender, weight, and mental health; females, patients of normal weight, and the mentally well were ranked the highest priority for access to a kidney dialysis machine. Participants discriminated most regarding the weight of hypothetical patients. Different patient characteristics, unrelated to medical prognoses, particularly being overweight, may have an impact on decisions regarding the use of scarce medical resources.

Stereomicroscope Inspection of Polished Aluminum Collector 50684.0

NASA Technical Reports Server (NTRS)

Rodriquez, M. C.; Calaway, M. J.; Allton, J. H.

2008-01-01

The Genesis polished aluminum "kidney" collector was damaged during the hard landing of the capsule on September 8, 2004 in the Utah desert. The kidney was introduced into the Genesis (ISO class 4) cleanroom laboratory on November 4, 2004 and stored under nitrogen cover gas. The collector is currently fastened to a highly polished stainless steel plate for secure handling. Curatorial work at JSC has made successful subdivision and subsequent allocation of samples from the kidney.

Analysis of 80 dual-kidney transplantations: a multicenter experience.

PubMed

Nardo, B; Bertelli, R; Cavallari, G; Capocasale, E; Cappelli, G; Mazzoni, M P; Benozzi, L; Dalla Valle, R; Fuga, G; Busi, N; Gilioli, C; Albertazzi, A; Stefoni, S; Pinna, A D; Faenza, A

2011-06-01

The use of kidneys from expanded criteria donors (ECD) is an attractive strategy to enlarge the pool of organs available for transplantation. Considering the fact that ECD organs have a reduced nephron mass, they are preferentially allocated for dual-kidney transplantation (DKT). Authors have reported excellent results of DKT when pretransplant ECD organs are evaluated for histological scores. The aim of this study was to evaluate DKT donor and recipient characteristics for comparison with DKT posttransplant outcomes versus those of recipients of single-kidney transplantations from expanded criteria (edSKT) and ideal donors (idSKT). We analyzed the potential prognostic factors involved in DKT among a population derived from three transplant centers. Between 2001 and 2007, DKT (n = 80) were performed based upon the ECD kidney allocation assessed by biopsy. The average donor ages for the DKT, edSKT, and idSKT groups were 68.8 ± 7.8, 65.3 ± 7.2, and 40.1 ± 13.8 years, respectively (P < .001). The number of human leukocyte antigen mismatches was greater in the DKT group (3.1 ± 1.2, P < .05). Patient and graft 5-year survival rates were similar among DKT, edSKT, and idSKT recipients, namely, 97.5% versus 95.8% versus 96.9% and 93.7% versus 87.4% versus 86.9%, respectively. Mean serum creatinine values at discharge were lower in the DKT and idSKT recipients (1.5 ± 0.9 and 1.6 ± 0.7 mg/dL; P < .05) compared with the edSKT group (1.9 ± 0.7 mg/dL). Correlations between supposed prognostic factors and survival among the DKT group noted worse outcomes in reoperation cases (P < .05). We confirmed that DKT produced successful outcomes. An accurate surgical procedure is particularly important to try to avoid reoperations. In our experience, the use of a biopsy as an absolute criterion to allocate ECD kidneys may be too protective. Copyright © 2011 Elsevier Inc. All rights reserved.

Renal Transplants from Older Deceased Donors: Use of Preimplantation Biopsy and Differential Allocation to Dual or Single Kidney Transplant according to Histological Score Has No Advantages over Allocation to Single Kidney Transplant by Simple Clinical Indication.

PubMed

Casati, Costanza; Colombo, Valeriana Giuseppina; Perrino, Marialuisa; Rossetti, Ornella Marina; Querques, Marialuisa; Giacomoni, Alessandro; Binaggia, Agnese; Colussi, Giacomo

2018-01-01

Grafts from elderly donors (ECD) are increasingly allocated to single (SKT) or dual (DKT) kidney transplantation according to biopsy score. Indications and benefits of either procedure lack universal agreement. A total of 302 ECD-transplants in period from Jan 1, 2000, to Dec 31, 2015, were allocated to SKT (SKT pre ) on clinical grounds alone (before Dec 2010, pre-DKT era, n = 170) or according to a clinical-histological protocol (after Dec 2010, DKT era, n = 132) to DKT ( n = 48), SKT biopsy-based protocol ("high-risk", SKT hr , n = 51), or SKT clinically based protocol ("low-risk", SKT lr , n = 33). Graft and patient survival were compared between the two periods and between different transplant categories. Graft and overall survival in recipients from ECD in pre-DKT and DKT era did not differ (5-year graft survival 87.7% and 84.2%, resp.); equal survival in the 2 ECD periods was shown in both donor age ranges of 60-69 and >70-years, and in low-risk or high-risk ECD categories. Within the DKT protocol SKT hr showed worst graft and overall survival in the 60-69 donor age range; DKT did not result in significantly better outcome than SKT from ECD in either era. One-year posttransplant creatinine clearance in recipients did not differ between any ECD transplant category. At 3 and 5 years after transplantation there were significantly higher total dialysis-free recipient life years from an equal donor number in the pre-DKT era than in the DKT protocol. Use of a biopsy-based protocol to allocate grafts from aged donors to SKT or DKT did not result in better short term graft survival than a clinically based protocol with allocation only to SKT and reduced overall recipient dialysis-free life years in time.

Renal Transplants from Older Deceased Donors: Use of Preimplantation Biopsy and Differential Allocation to Dual or Single Kidney Transplant according to Histological Score Has No Advantages over Allocation to Single Kidney Transplant by Simple Clinical Indication

PubMed Central

Casati, Costanza; Colombo, Valeriana Giuseppina; Perrino, Marialuisa; Rossetti, Ornella Marina; Querques, Marialuisa; Giacomoni, Alessandro; Binaggia, Agnese

2018-01-01

Background Grafts from elderly donors (ECD) are increasingly allocated to single (SKT) or dual (DKT) kidney transplantation according to biopsy score. Indications and benefits of either procedure lack universal agreement. Methods A total of 302 ECD-transplants in period from Jan 1, 2000, to Dec 31, 2015, were allocated to SKT (SKTpre) on clinical grounds alone (before Dec 2010, pre-DKT era, n = 170) or according to a clinical-histological protocol (after Dec 2010, DKT era, n = 132) to DKT (n = 48), SKT biopsy-based protocol (“high-risk”, SKThr, n = 51), or SKT clinically based protocol (“low-risk”, SKTlr, n = 33). Graft and patient survival were compared between the two periods and between different transplant categories. Results Graft and overall survival in recipients from ECD in pre-DKT and DKT era did not differ (5-year graft survival 87.7% and 84.2%, resp.); equal survival in the 2 ECD periods was shown in both donor age ranges of 60–69 and >70-years, and in low-risk or high-risk ECD categories. Within the DKT protocol SKThr showed worst graft and overall survival in the 60–69 donor age range; DKT did not result in significantly better outcome than SKT from ECD in either era. One-year posttransplant creatinine clearance in recipients did not differ between any ECD transplant category. At 3 and 5 years after transplantation there were significantly higher total dialysis-free recipient life years from an equal donor number in the pre-DKT era than in the DKT protocol. Conclusions Use of a biopsy-based protocol to allocate grafts from aged donors to SKT or DKT did not result in better short term graft survival than a clinically based protocol with allocation only to SKT and reduced overall recipient dialysis-free life years in time. PMID:29862061

CPRA for allocation of kidneys in the US: More candidates ≥98% CPRA, lower positive crossmatch rates and improved transplant rates for sensitized patients.

PubMed

Baxter-Lowe, Lee Ann; Kucheryavaya, Anna; Tyan, Dolly; Reinsmoen, Nancy

2016-05-01

In 2009 calculated panel reactive antibody (CPRA) replaced PRA as the metric for HLA sensitization in the US kidney allocation system. During the next four years, registrants with at least one unacceptable antigen increased (34-40%) and registrants with ≥98% PRA/CPRA increased from 7% to 9% of the waitlist. These changes were accompanied by a reduction in kidney offers refused for positive crossmatch: 14,137 (1.7%) in 2009 and 3,310 in 2013 (0.4%). Registrants with ≥98% PRA/CPRA had highest rates of refusal but also showed substantial improvement (20% in 2009 vs 8% in 2013). For registrants with ≥98% PRA/CPRA, 45% of accepted offers in 2009 were not transplanted into the intended recipient compared to 11% in 2013. Transplant rates remained low for these patients (∼50/1000 active patient-years), but rates improved for patients with 80-97% PRA/CPRA (223/1000 active patient-years in 2009 vs 354/1000 in 2013). In 2013, 40% regraft candidates had CPRA ≥98% compared to 4% of primary graft candidates. More females than males were ≥98% CPRA (14% vs 7%) and more females had CPRA above 0 (50% vs 28%). In the CPRA era, listing of unacceptable antigens increased, positive crossmatches were diminished and transplant rates for sensitized patients improved. Copyright © 2016 American Society for Histocompatibility and Immunogenetics. All rights reserved.

Kidney and liver transplantation in the elderly.

PubMed

Sutherland, A I; IJzermans, J N M; Forsythe, J L R; Dor, F J M F

2016-01-01

Transplant surgery is facing a shortage of deceased donor organs. In response, the criteria for organ donation have been extended, and an increasing number of organs from older donors are being used. For recipients, the benefits of transplantation are great, and the growing ageing population has led to increasing numbers of elderly patients being accepted for transplantation. The literature was reviewed to investigate the impact of age of donors and recipients in abdominal organ transplantation, and to highlight aspects of the fine balance in donor and recipient selection and screening, as well as allocation policies fair to young and old alike. Overall, kidney and liver transplantation from older deceased donors have good outcomes, but are not as good as those from younger donors. Careful donor selection based on risk indices, and potentially biomarkers, special allocation schemes to match elderly donors with elderly recipients, and vigorous recipient selection, allows good outcomes with increasing age of both donors and recipients. The results of live kidney donation have been excellent for donor and recipient, and there is a trend towards inclusion of older donors. Future strategies, including personalized immunosuppression for older recipients as well as machine preservation and reconditioning of donor organs, are promising ways to improve the outcome of transplantation between older donors and older recipients. Kidney and liver transplantation in the elderly is a clinical reality. Outcomes are good, but can be optimized by using strategies that modify donor risk factors and recipient co-morbidities, and personalized approaches to organ allocation and immunosuppression. © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

Individualized therapy to prevent bone mineral density loss after kidney and kidney-pancreas transplantation.

PubMed

Mainra, Rahul; Elder, Grahame J

2010-01-01

Most patients who undergo kidney or kidney-pancreas transplantation have renal osteodystrophy, and immediately after transplantation bone mineral density (BMD) commonly falls. Together, these abnormalities predispose to an increased fracture incidence. Bisphosphonate or calcitriol therapy can preserve BMD after transplantation, but although bisphosphonates may be more effective, they pose potential risks for adynamic bone. A total of 153 kidney (61%) and kidney-pancreas (39%) transplant recipients were allocated to bisphosphonate (62%) or calcitriol (38%) therapy using an algorithm that incorporated BMD, prevalent vertebral fracture, biomarkers of bone turnover, and risk factor assessment. Patients received cholecalciferol and calcium as appropriate and were followed for 12 mo. Patients who were treated with bisphosphonates had lower BMD at the lumbar spine and femoral neck and longer time on dialysis. Age and gender were similar between the groups. At 12 mo, bisphosphonate-treated patients had significant BMD increases at the lumber spine and femoral neck and a negative trend at the wrist. Patients who were allocated to calcitriol, who were assessed to have lower baseline fracture risk, had no significant change in BMD at any site. At 1 yr, mean levels of bone turnover marker and intact parathyroid hormone normalized in both groups. Incident fracture rates did not differ significantly. With targeted treatment, BMD levels were stable or improved and bone turnover markers normalized. This algorithm provides a guide to targeting therapy after transplantation that avoids BMD loss and may reduce suppression of bone turnover.

Sirolimus in kidney transplant donors and clinical and histologic improvement in recipients: rat model.

PubMed

Cicora, F; Lausada, N; Vasquez, D N; Cicora, P; Zalazar, G; Gonzalez, P; Palti, G; Raimondi, C

2010-01-01

Ischemia-reperfusion (I/R) injury is one of the risk factors for delayed graft function, acute rejection episodes, and impaired long-term allograft survival after kidney transplantation. This antigen-independent inflammatory process produces tissue damage. Isogeneic transplantation in a rat model is a useful method for study of nonimmunologic risk factors for kidney damage. To study the effect of sirolimus on I/R injury using only 1 dose of the drug in the donor. Eighteen rats were allocated to 3 groups of 6 rats each: sham group, control group, and rapamycin group. Improved renal function and systemic inflammatory response were observed in the rapamycin group compared with the control group (Deltaurea, Deltacreatinine, and DeltaC3, all P < .01). The number of apoptotic nuclei in the renal medulla in the control group was higher than in the rapamycin group (P < .01). Tubular damage was less severe in the rapamycin group compared with the control group (P < .01). Complement 3 and tumor necrosis factor-alpha expression in the kidney samples were significantly decreased when rapamycin was given to the donor rats (P > .01). Bcl-2 protein was upregulated in the rapamycin group compared with the control group (P < .01). Administration of rapamycin in donors attenuates the I/R injury process after kidney transplantation in a rat model.

Kidney allocation to liver transplant candidates with renal failure of undetermined etiology: role of percutaneous renal biopsy.

PubMed

Wadei, H M; Geiger, X J; Cortese, C; Mai, M L; Kramer, D J; Rosser, B G; Keaveny, A P; Willingham, D L; Ahsan, N; Gonwa, T A

2008-12-01

The feasibility, value and risk of percutaneous renal biopsy (PRB) in liver transplant candidates with renal failure are unknown. PRB was performed on 44 liver transplant candidates with renal failure of undetermined etiology and glomerular filtration rate (GFR) <40 mL/min/1.73 m(2) (n = 37) or on renal replacement therapy (RRT) (n = 7). Patients with >or=30% interstitial fibrosis (IF), >or=40% global glomerulosclerosis (gGS) and/or diffuse glomerulonephritis were approved for simultaneous-liver-kidney (SLK) transplantation. Prebiopsy GFR, urinary sodium indices, dependency on RRT and kidney size were comparable between 27 liver-transplant-alone (LTA) and 17 SLK candidates and did not relate to the biopsy diagnosis. The interobserver agreement for the degree of IF or gGS was moderate-to-excellent. After a mean of 78 +/- 67 days, 16 and 8 patients received LTA and SLK transplants. All five LTA recipients on RRT recovered kidney function after transplantation and serum creatinine was comparable between LTA and SLK recipients at last follow-up. Biopsy complications developed in 13, of these, five required intervention. PRB is feasible in liver transplant candidates with renal failure and provides reproducible histological information that does not relate to the pretransplant clinical data. Randomized studies are needed to determine if PRB can direct kidney allocation in this challenging group of liver transplant candidates.

First UK case report of kidney transplantation from an HIV-infected deceased donor to two HIV-infected recipients.

PubMed

Nolan, Eileen; Karydis, Nikolaos; Drage, Martin; Hilton, Rachel

2018-04-01

Kidney transplantation is now considered the treatment of choice for many human immunodeficiency virus (HIV)-infected patients with end-stage renal disease (ESRD). Graft survival rates using HIV-negative donors and carefully selected HIV-positive ESRD patients are similar to those observed in HIV-uninfected kidney transplant recipients. To address the relative shortfall in donated organs it has been proposed that organs from HIV-infected deceased donors might be allocated to HIV-infected patients on the transplant waiting list. Preliminary experience in South Africa reports promising short-term outcomes in a small number of HIV-infected recipients of kidney transplants from HIV-infected donors. We sought to replicate this experience in the UK by accepting kidney offers from HIV infected deceased donors for patients with HIV-infection on the kidney transplant waiting list. Here we report the UK's first cases of kidney transplantation between HIV-positive donors and recipients.

Recent advances in kidney transplantation: a viewpoint from the Descartes advisory board.

PubMed

Abramowicz, Daniel; Oberbauer, Rainer; Heemann, Uwe; Viklicky, Ondrej; Peruzzi, Licia; Mariat, Christophe; Crespo, Marta; Budde, Klemens; Oniscu, Gabriel C

2018-01-12

Transplantation medicine is a rapidly evolving field. Keeping afloat of the published literature to offer the best clinical care to our patients is a daunting task. As part of its educational mission, the Descartes advisory board identified seven topics in kidney transplantation where there has been substantial progresses over the last years: kidney allocation within Eurotransplant; kidney exchange strategies; kidney machine perfusion strategies; the changing landscape of anti-human leukocyte antigen (HLA) antibodies; the new immunosuppressive drugs in the pipeline; strategies for immunosuppression minimization; and the continuous enigma of focal segmental glomerular sclerosis recurrence after transplantation. Here, we have summarized the main knowledge and the main challenges of these seven topics with the aim to provide transplant professionals at large with key bullet points to successfully understand these new concepts.

Simpler and equitable allocation of kidneys from postmortem donors primarily based on full HLA-DR compatibility.

PubMed

Doxiadis, Ilias I N; de Fijter, Johan W; Mallat, Marko J K; Haasnoot, Geert W; Ringers, Jan; Persijn, Guido G; Claas, Frans H J

2007-05-15

The introduction of human leukocyte antigen (HLA)-matching in nonliving kidney transplantation has resulted into a better graft outcome, but also in an increase of waiting time, especially for patients with rare HLA phenotypes. We addressed the question of the differential influence of HLA-DR-matching versus HLA-A,B in clinical kidney transplantation. We used Kaplan-Meier product limit method to estimate survival rates, and Cox proportional hazard regression for the estimation of relative risks (Hazard-ratios) for different variables. A single center study (n=456 transplants, performed between 1985 and 1999) showed that full HLA-DR compatibility leads to a lower incidence of biopsy confirmed acute rejections in the first 180 posttransplantation days. These results were substantiated using the Eurotransplant database (n=39,205 transplants performed between 1985 and 2005) where graft survival in the full HLA-DR compatible group was significantly better than in the incompatible. An additional positive effect of HLA-A,B matching was only found in the full HLA-DR compatible group. In both studies, the introduction of a single HLA-DR incompatibility eliminates the HLA-A,B matching effect. We propose to allocate postmortem kidneys only to patients with full HLA-DR compatibility, and use HLA-A,B compatibility as an additional selection criterion. All patients, irrespective of their ethnic origin, will profit since the polymorphism of HLA-DR is by far lower than that of HLA-A,B. Excessive kidney travel and cold ischemia time will be significantly reduced.

Acute kidney injury in acute liver failure: a review.

PubMed

Moore, Joanna K; Love, Eleanor; Craig, Darren G; Hayes, Peter C; Simpson, Kenneth J

2013-11-01

Acute liver failure is a rare and often devastating condition consequent on massive liver cell necrosis that frequently affects young, previously healthy individuals resulting in altered cognitive function, coagulopathy and peripheral vasodilation. These patients frequently develop concurrent acute kidney injury (AKI). This abrupt and sustained decline in renal function, through a number of pathogenic mechanisms such as renal hypoperfusion, direct drug-induced nephrotoxicity or sepsis/systemic inflammatory response contributes to increased morbidity and is strongly associated with a worse prognosis. Improved understanding of the pathophysiology AKI in the context of acute liver failure may be beneficial in a number of areas; the development of new and sensitive biomarkers of renal dysfunction, refining prognosis and organ allocation, and ultimately leading to the development of novel treatment strategies, these issues are discussed in more detail in this expert review.

First UK case report of kidney transplantation from an HIV-infected deceased donor to two HIV-infected recipients

PubMed Central

Nolan, Eileen; Karydis, Nikolaos; Drage, Martin

2018-01-01

Abstract Kidney transplantation is now considered the treatment of choice for many human immunodeficiency virus (HIV)-infected patients with end-stage renal disease (ESRD). Graft survival rates using HIV-negative donors and carefully selected HIV-positive ESRD patients are similar to those observed in HIV-uninfected kidney transplant recipients. To address the relative shortfall in donated organs it has been proposed that organs from HIV-infected deceased donors might be allocated to HIV-infected patients on the transplant waiting list. Preliminary experience in South Africa reports promising short-term outcomes in a small number of HIV-infected recipients of kidney transplants from HIV-infected donors. We sought to replicate this experience in the UK by accepting kidney offers from HIV infected deceased donors for patients with HIV-infection on the kidney transplant waiting list. Here we report the UK’s first cases of kidney transplantation between HIV-positive donors and recipients. PMID:29644073

Acute Kidney Injury after Liver Transplantation.

PubMed

Durand, François; Francoz, Claire; Asrani, Sumeet K; Khemichian, Saro; Pham, Thomas A; Sung, Randall S; Genyk, Yuri S; Nadim, Mitra K

2018-05-29

Since the implementation of the MELD score-based allocation system, the number of transplant candidates with impaired renal function has increased. The aims of this review are to present new insights in the definitions and predisposing factors that result in acute kidney injury (AKI), and to propose guidelines for the prevention and treatment of post liver transplantation (LT) AKI. This review is based on both systematic review of relevant literature and expert opinion. Pretransplant AKI is associated with posttransplant morbidity, including prolonged post LT AKI which then predisposes to posttransplant chronic kidney disease (CKD). Prevention of posttransplant AKI is essential in the improvement of long term outcomes. Accurate assessment of baseline kidney function at evaluation is necessary, taking into account that serum creatinine overestimates glomerular filtration rate (GFR). New diagnostic criteria for AKI have been integrated with traditional approaches in patients with cirrhosis to potentially identify AKI earlier and improve outcomes. Delayed introduction or complete elimination of calcineurin inhibitors during the first weeks post LT in patients with early posttransplant AKI may improve GFR in high risk patients but with higher rates of rejection and more adverse events. Biomarkers may in the future provide diagnostic information such as etiology of AKI, and prognostic information on renal recovery post-LT, and potentially impact the decision for simultaneous liver-kidney transplantation. Overall, more attention should be paid to pretransplant and early posttransplant AKI to reduce the burden of late CKD.

Decision Making in Kidney Paired Donation Programs with Altruistic Donors*

PubMed Central

Li, Yijiang; Song, Peter X.-K.; Leichtman, Alan B.; Rees, Michael A.; Kalbfleisch, John D.

2014-01-01

In recent years, kidney paired donation (KPD) has been extended to include living non-directed or altruistic donors, in which an altruistic donor donates to the candidate of an incompatible donor-candidate pair with the understanding that the donor in that pair will further donate to the candidate of a second pair, and so on; such a process continues and thus forms an altruistic donor-initiated chain. In this paper, we propose a novel strategy to sequentially allocate the altruistic donor (or bridge donor) so as to maximize the expected utility; analogous to the way a computer plays chess, the idea is to evaluate different allocations for each altruistic donor (or bridge donor) by looking several moves ahead in a derived look-ahead search tree. Simulation studies are provided to illustrate and evaluate our proposed method. PMID:25309603

[Chronic kidney disease and kidney transplantation].

PubMed

Thuret, R; Timsit, M O; Kleinclauss, F

2016-11-01

To report epidemiology and characteristics of end-stage renal disease (ESRD) patients and renal transplant candidates, and to evaluate access to waiting list and results of renal transplantation. An exhaustive systematic review of the scientific literature was performed in the Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com) using different associations of the following keywords: "chronic kidney disease, epidemiology, kidney transplantation, cost, survival, graft, brain death, cardiac arrest, access, allocation". French legal documents have been reviewed using the government portal (http://www.legifrance.gouv.fr). Articles were selected according to methods, language of publication and relevance. The reference lists were used to identify additional historical studies of interest. Both prospective and retrospective series, in French and English, as well as review articles and recommendations were selected. In addition, French national transplant and health agencies (http://www.agence-biomedecine.fr and http://www.has-sante.fr) databases were screened using identical keywords. A total of 3234 articles, 6 official reports and 3 newspaper articles were identified; after careful selection 99 publications were eligible for our review. The increasing prevalence of chronic kidney disease (CKD) leads to worsen organ shortage. Renal transplantation remains the best treatment option for ESRD, providing recipients with an increased survival and quality of life, at lower costs than other renal replacement therapies. The never-ending lengthening of the waiting list raises issues regarding treatment strategies and candidates' selection, and underlines the limits of organ sharing without additional source of kidneys available for transplantation. Allocation policies aim to reduce medical or geographical disparities regarding enrollment on a waiting list or access to an allotransplant. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Organ Vouchers and Barter Markets: Saving Lives, Reducing Suffering, and Trading in Human Organs.

PubMed

Cherry, Mark J

2017-10-01

The essays in this issue of The Journal of Medicine and Philosophy explore an innovative voucher program for encouraging kidney donation. Discussions cluster around a number of central moral and political/theoretical themes: (1) What are the direct and indirect health care costs and benefits of such a voucher system in human organs? (2) Do vouchers lead to more effective and efficient organ procurement and allocation or contribute to greater inequalities and inefficiencies in the transplantation system? (3) Do vouchers contribute to the inappropriate commodification of human body parts? (4) Is there a significant moral difference between such a voucher system and a market in human organs for transplantation? This paper argues that while kidney vouchers constitute a step in the right direction, fuller utilization of market-based incentives, including, but not limited to, barter exchanges (e.g., organ exchanges, organ chains, and organ vouchers), would save more lives and further reduce human suffering. © The Author 2017. Published by Oxford University Press, on behalf of the Journal of Medicine and Philosophy Inc. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Simultaneous Liver-Kidney Transplantation: Impact on Liver Transplant Patients and the Kidney Transplant Waiting List.

PubMed

Miles, Clifford D; Westphal, Scott; Liapakis, AnnMarie; Formica, Richard

2018-01-01

The number of simultaneous liver-kidney transplants (SLKT) performed in the USA has been rising. The Organ Procurement and Transplantation Network implemented a new policy governing SLKT that specifies eligibility criteria for candidates to receive a kidney with a liver, and creates a kidney waitlist "safety net" for liver recipients with persistent renal failure after transplant. This review explores potential impacts for liver patients and the kidney waitlist. Factors that have contributed to the rise in SLKT including Model for End-stage Liver Disease (MELD)-based allocation, regional sharing for high MELD candidates, and the rising incidence of non-alcoholic steatohepatitis will continue to increase the number of liver transplant candidates with concurrent renal insufficiency. The effect of center behavior based on the new policy is harder to predict, given wide historic variability in SLKT practice. Continued increase in combined liver/kidney failure is likely, and SLKT and kidney after liver transplant may both increase. Impact of the new policy should be carefully monitored, but influences beyond the policy need to be accounted for.

The PROCARE consortium: toward an improved allocation strategy for kidney allografts.

PubMed

Otten, H G; Joosten, I; Allebes, W A; van der Meer, A; Hilbrands, L B; Baas, M; Spierings, E; Hack, C E; van Reekum, F; van Zuilen, A D; Verhaar, M C; Bots, M L; Seelen, M A J; Sanders, J S F; Hepkema, B G; Lambeck, A J; Bungener, L B; Roozendaal, C; Tilanus, M G J; Vanderlocht, J; Voorter, C E; Wieten, L; van Duijnhoven, E; Gelens, M; Christiaans, M; van Ittersum, F; Nurmohamed, A; Lardy, N M; Swelsen, W T; van Donselaar-van der Pant, K A M I; van der Weerd, N C; Ten Berge, I J M; Bemelman, F J; Hoitsma, A J; de Fijter, J W; Betjes, M G H; Roelen, D L; Claas, F H J

2014-10-01

Kidney transplantation is the best treatment option for patients with end-stage renal failure. At present, approximately 800 Dutch patients are registered on the active waiting list of Eurotransplant. The waiting time in the Netherlands for a kidney from a deceased donor is on average between 3 and 4 years. During this period, patients are fully dependent on dialysis, which replaces only partly the renal function, whereas the quality of life is limited. Mortality among patients on the waiting list is high. In order to increase the number of kidney donors, several initiatives have been undertaken by the Dutch Kidney Foundation including national calls for donor registration and providing information on organ donation and kidney transplantation. The aim of the national PROCARE consortium is to develop improved matching algorithms that will lead to a prolonged survival of transplanted donor kidneys and a reduced HLA immunization. The latter will positively affect the waiting time for a retransplantation. The present algorithm for allocation is among others based on matching for HLA antigens, which were originally defined by antibodies using serological typing techniques. However, several studies suggest that this algorithm needs adaptation and that other immune parameters which are currently not included may assist in improving graft survival rates. We will employ a multicenter-based evaluation on 5429 patients transplanted between 1995 and 2005 in the Netherlands. The association between key clinical endpoints and selected laboratory defined parameters will be examined, including Luminex-defined HLA antibody specificities, T and B cell epitopes recognized on the mismatched HLA antigens, non-HLA antibodies, and also polymorphisms in complement and Fc receptors functionally associated with effector functions of anti-graft antibodies. From these data, key parameters determining the success of kidney transplantation will be identified which will lead to the identification of additional parameters to be included in future matching algorithms aiming to extend survival of transplanted kidneys and to diminish HLA immunization. Computer simulation studies will reveal the number of patients having a direct benefit from improved matching, the effect on shortening of the waiting list, and the decrease in waiting time. Copyright © 2014. Published by Elsevier B.V.

Measuring and monitoring equity in access to deceased donor kidney transplantation.

PubMed

Stewart, D E; Wilk, A R; Toll, A E; Harper, A M; Lehman, R R; Robinson, A M; Noreen, S A; Edwards, E B; Klassen, D K

2018-05-07

The Organ Procurement and Transplantation Network monitors progress toward strategic goals such as increasing the number of transplants and improving waitlisted patient, living donor, and transplant recipient outcomes. However, a methodology for assessing system performance in providing equity in access to transplants was lacking. We present a novel approach for quantifying the degree of disparity in access to deceased donor kidney transplants among waitlisted patients and determine which factors are most associated with disparities. A Poisson rate regression model was built for each of 29 quarterly, period-prevalent cohorts (January 1, 2010-March 31, 2017; 5 years pre-kidney allocation system [KAS], 2 years post-KAS) of active kidney waiting list registrations. Inequity was quantified as the outlier-robust standard deviation (SD w ) of predicted transplant rates (log scale) among registrations, after "discounting" for intentional, policy-induced disparities (eg, pediatric priority) by holding such factors constant. The overall SD w declined by 40% after KAS implementation, suggesting substantially increased equity. Risk-adjusted, factor-specific disparities were measured with the SD w after holding all other factors constant. Disparities associated with calculated panel-reactive antibodies decreased sharply. Donor service area was the factor most associated with access disparities post-KAS. This methodology will help the transplant community evaluate tradeoffs between equity and utility-centric goals when considering new policies and help monitor equity in access as policies change. © 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.

Advanced Donation Programs and Deceased Donor-Initiated Chains-2 Innovations in Kidney Paired Donation.

PubMed

Wall, Anji E; Veale, Jeffrey L; Melcher, Marc L

2017-12-01

Kidney paired donation (KPD) strategies have facilitated compatible living-donor kidney transplants for end-stage renal disease patients with willing but incompatible living donors. Success has inspired further innovations that expand opportunities for kidney-paired donation. Two such innovations are the advanced donation strategy in which a donor provides a kidney before their recipient is matched, or even in need of, a kidney transplant, and deceased donor initiated chains in which chains are started with deceased donors rather than altruistic living donors. Although these innovations may expand KPD, they raise several ethical issues. Specific concerns raised by advanced donation include the management of uncertainty, the extent of donor and recipient consent, the scope of the obligation that the organization has to the kidney exchange paired recipient, the naming of alternative recipients, and the potential to unfairly advantage the recipient. Use of deceased donors for chain-initiating kidneys raises ethical issues concerning the consent process for each involved party, the prioritization of deceased donor kidneys, the allocation of chain ending kidneys, and the value of a living donor kidney versus a deceased donor kidney. We outline each ethical issue and discuss how it can be conceptualized and managed so that these KPD innovations programs are ultimately successful.

Cultural competency of a mobile, customized patient education tool for improving potential kidney transplant recipients' knowledge and decision-making.

PubMed

Axelrod, David A; Kynard-Amerson, Crystal S; Wojciechowski, David; Jacobs, Marie; Lentine, Krista L; Schnitzler, Mark; Peipert, John D; Waterman, Amy D

2017-05-01

Patients considering renal transplantation face an increasingly complex array of choices as a result of the revised kidney transplant allocation system. Decision aids have been shown to improve patient decision-making through the provision of detailed, relevant, individualized clinical data. A mobile iOS-based application (app) including animated patient education and individualized risk-adjusted outcomes following kidney transplants with varying donor characteristics and DSA waiting times was piloted in two large US transplant programs with a diverse group of renal transplant candidates (N = 81). The majority (86%) of patients felt that the app improved their knowledge and was culturally appropriate for their race/ethnicity (67%-85%). Patients scored significantly higher on transplant knowledge testing (9.1/20 to 13.8/20, P < .001) after viewing the app, including patients with low health literacy (8.0 to 13.0, P < .001). Overall knowledge of and interest in living and deceased donor kidney transplantation increased. This pilot project confirmed the benefit and cultural acceptability of this educational tool, and further refinement will explore how to better communicate the risks and benefits of nonstandard donors. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Rethinking the advantage of zero-HLA mismatches in unrelated living donor kidney transplantation: implications on kidney paired donation.

PubMed

Casey, Michael Jin; Wen, Xuerong; Rehman, Shehzad; Santos, Alfonso H; Andreoni, Kenneth A

2015-04-01

The OPTN/UNOS Kidney Paired Donation (KPD) Pilot Program allocates priority to zero-HLA mismatches. However, in unrelated living donor kidney transplants (LDKT)-the same donor source in KPD-no study has shown whether zero-HLA mismatches provide any advantage over >0 HLA mismatches. We hypothesize that zero-HLA mismatches among unrelated LDKT do not benefit graft survival. This retrospective SRTR database study analyzed LDKT recipients from 1987 to 2012. Among unrelated LDKT, subjects with zero-HLA mismatches were compared to a 1:1-5 matched (by donor age ±1 year and year of transplantation) control cohort with >0 HLA mismatches. The primary endpoint was death-censored graft survival. Among 32,654 unrelated LDKT recipients, 83 had zero-HLA mismatches and were matched to 407 controls with >0 HLA mismatches. Kaplan-Meier analyses for death-censored graft and patient survival showed no difference between study and control cohorts. In multivariate marginal Cox models, zero-HLA mismatches saw no benefit with death-censored graft survival (HR = 1.46, 95% CI 0.78-2.73) or patient survival (HR = 1.43, 95% CI 0.68-3.01). Our data suggest that in unrelated LDKT, zero-HLA mismatches may not offer any survival advantage. Therefore, particular study of zero-HLA mismatching is needed to validate its place in the OPTN/UNOS KPD Pilot Program allocation algorithm. © 2014 Steunstichting ESOT.

Organ allocation in pediatric renal transplants: is there an optimal donor?

PubMed

Pitt, Susan C; Vachharajani, Neeta; Doyle, Maria B; Lowell, Jeffrey A; Chapman, William C; Anderson, Christopher D; Shenoy, Surendra; Wellen, Jason R

2013-01-01

The 2005 revised allocation scheme for pediatric renal transplantation made the decision of whether to transplant an available living-donor (LD) kidney or use a deceased-donor (DD) kidney controversial. The aim of this study was to examine kidney allograft utilization, sensitization, and outcomes of pediatric transplant recipients. Between January 2000 and December 2009, 91 consecutive pediatric kidney recipients (<20 yr) were transplanted. The LD (n = 38) and DD (n = 53) groups were similar in age, gender, dialysis status at transplant, warm ischemia time, and overall patient survival. LD recipients were more likely to be Caucasian (92 vs. 69%), receive older allografts (39 ± 10 vs. 23 ± 9 yr), and have fewer human leukocyte antigen (HLA) mismatches (3.3 ± 1.6 vs. 4.4 ± 1.5, p < 0.01 for all). Graft survival at one, three, and five yr post-transplant was longer for LD recipients (97%, 91%, 87% vs. DD 89%, 79%, 58%, respectively, p < 0.05). At the time of transplant, 17 (33%) DD recipients had an available LD (mean age 40 yr). A greater proportion of all patients were moderately (PRA 21-79%) sensitized post-transplant (p < 0.05). A multivariable analysis of graft survival indicated that the advantage in LD organs was likely due to fewer HLA mismatched in this group. Nonetheless, LD organs appear to provide optimal outcomes in pediatric renal transplants when considering the risk of becoming sensitized post-transplant complicating later use of the LD kidney. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The kidney cancer research priority-setting partnership: Identifying the top 10 research priorities as defined by patients, caregivers, and expert clinicians.

PubMed

Jones, Jennifer; Bhatt, Jaimin; Avery, Jonathan; Laupacis, Andreas; Cowan, Katherine; Basappa, Naveen; Basiuk, Joan; Canil, Christina; Al-Asaaed, Sohaib; Heng, Daniel; Wood, Lori; Stacey, Dawn; Kollmannsberger, Christian; Jewett, Michael A S

2017-12-01

It is critically important to define disease-specific research priorities to better allocate limited resources. There is growing recognition of the value of involving patients and caregivers, as well as expert clinicians in this process. To our knowledge, this has not been done this way for kidney cancer. Using the transparent and inclusive process established by the James Lind Alliance, the Kidney Cancer Research Network of Canada (KCRNC) sponsored a collaborative consensus-based priority-setting partnership (PSP) to identify research priorities in the management of kidney cancer. The final result was identification of 10 research priorities for kidney cancer, which are discussed in the context of current initiatives and gaps in knowledge. This process provided a systematic and effective way to collaboratively establish research priorities with patients, caregivers, and clinicians, and provides a valuable resource for researchers and funding agencies.

A2 to B Blood Type Incompatible Deceased Donor Kidney Transplantation in a Recipient Infected with the Human Immunodeficiency Virus: A Case Report.

PubMed

Forbes, R C; DeMers, A; Concepcion, B P; Moore, D R; Schaefer, H M; Shaffer, D

With the introduction of the Kidney Allocation System in the United States in December 2014, transplant centers can list eligible B blood type recipients for A2 organ offers. There have been no prior reports of ABO incompatible A2 to B deceased donor kidney transplantation in human immunodeficiency virus-positive (HIV+) recipients to guide clinicians on enrolling or performing A2 to B transplantations in HIV+ candidates. We are the first to report a case of A2 to B deceased donor kidney transplantation in an HIV+ recipient with good intermediate-term results. We describe an HIV+ 39-year-old African American man with end-stage renal disease who underwent A2 to B blood type incompatible deceased donor kidney transplantation. Prior to transplantation, he had an undetectable HIV viral load. The patient was unsensitized, with his most recent anti-A titer data being 1:2 IgG and 1:32 IgG/IgM. Induction therapy of basiliximab and methylprednisolone was followed by a postoperative regimen of plasma exchange, intravenous immunoglobulin, and rituximab with maintenance on tacrolimus, mycophenolate mofetil, and prednisone. He had delayed graft function without rejection on allograft biopsy. Nadir serum creatinine was 2.0 mg/dL. He continued to have an undetectable viral load on the same antiretroviral therapy adjusted for renal function. To our knowledge, this is the first report of A2 to B deceased donor kidney transplantation in an HIV+ recipient with good intermediate-term results, suggesting that A2 donor kidneys may be considered for transplantation into HIV+ B-blood type wait list candidates. Published by Elsevier Inc.

Effects of pre-transplant azithromycin administration on kidney graft function: study protocol for a double-blind randomized clinical trial.

PubMed

Mokhtari, Gholamreza; Teimoori, Mojtaba

2018-06-28

Kidney transplantation is the best strategy for the management of end-stage renal disease; however, the outcomes need to improve further. Macrolides show antimicrobial and anti-inflammatory properties in chronic diseases and intraoperatively, and can accumulate in tissues for extended periods. Therefore, theoretically, when administered to a donor and because of accumulation in the donor kidney, macrolides can cause graft immunomodulation and improve kidney transplantation outcomes. This study is a single-center, randomized clinical trial. A total of 60 kidney donors will be randomly allocated to the azithromycin or placebo group and treated with a single dose (1 g) of azithromycin or placebo, respectively, 1 day before surgery. Recruitment commenced in September 2016 and is expected to be completed by March 2018. The primary outcome is kidney graft function. The secondary outcomes include rejection rate, urinary tract infections in graft recipients, pain and systemic inflammatory response syndrome in live donors, and complications in both donors and recipients. Outcomes will be evaluated at baseline and every day in the first week after transplantation, as well as at 1 and 3 months post transplantation. Adverse reactions will be documented. If the efficacy of azithromycin in reducing adverse outcomes is confirmed, it would serve as an easy to use, economic intervention able to lower post-transplantation risks. Short and mid-term analyses of blood and urine samples as well as immunological assays will facilitate a more in-depth analysis of the effects of azithromycin on transplantation outcomes. Iranian Clinical Trial Registry, IRCT201606141853N11 , registered on September 5, 2016.

Regulated compensation for kidney donors in the Philippines.

PubMed

Padilla, Benita S

2009-04-01

The purpose of this review is to discuss the recent events and experiences in the Philippines related to compensated kidney donation. Between 2002 and 2008, the Philippine government, through the Department of Health, administered a program called the Philippine Organ Donation Program that allowed prospective kidney providers to sign up, be allocated to prospective recipients and receive gratuities for their kidney. Transplant tourism flourished during this period because of rampant disregard for the regulation limiting foreign recipients to 10% of total kidney transplants. There is evidence of inadequate donor care. Efforts to curb the problem included a ban on foreigners coming to the Philippines to have kidney transplants with Filipinos as donors as well as strengthening of the implementing rules and regulations of both the antihuman trafficking law and the organ donation law that allowed donation after brain death. The experience in the Philippines mirrored those in India and Pakistan where paid donors reported poor outcomes. An effective national kidney disease prevention program and the deceased donor program for transplantation should be aggressively promoted. Legislation against transplant commercialism is needed.

Past, present and future of kidney paired donation transplantation in India

PubMed Central

Kute, Vivek B; Patel, Himanshu V; Shah, Pankaj R; Modi, Pranjal R; Shah, Veena R; Rizvi, Sayyed J; Pal, Bipin C; Modi, Manisha P; Shah, Priya S; Varyani, Umesh T; Wakhare, Pavan S; Shinde, Saiprasad G; Ghodela, Vijay A; Patel, Minaxi H; Trivedi, Varsha B; Trivedi, Hargovind L

2017-01-01

One third of healthy willing living kidney donors are rejected due to ABO blood group incompatibility and donor specific antibody. This increases pre-transplant dialysis duration leading to increased morbidity and mortality on the kidney transplantation waiting list. Over the last decade kidney paired donation is most rapidly increased source of living kidney donors. In a kidney transplantation program dominated by living donor kidney transplantation, kidney paired donation is a legal and valid alternative strategy to increase living donor kidney transplantation. This is more useful in countries with limited resources where ABO incompatible kidney transplantation or desensitization protocol is not feasible because of costs/infectious complications and deceased donor kidney transplantation is in initial stages. The matching allocation, ABO blood type imbalance, reciprocity, simultaneity, geography were the limitation for the expansion of kidney paired donation. Here we describe different successful ways to increase living donor kidney transplantation through kidney paired donation. Compatible pairs, domino chain, combination of kidney paired donation with desensitization or ABO incompatible transplantation, international kidney paired donation, non-simultaneous, extended, altruistic donor chain and list exchange are different ways to expand the donor pool. In absence of national kidney paired donation program, a dedicated kidney paired donation team will increase access to living donor kidney transplantation in individual centres with team work. Use of social networking sites to expand donor pool, HLA based national kidney paired donation program will increase quality and quantity of kidney paired donation transplantation. Transplant centres should remove the barriers to a broader implementation of multicentre, national kidney paired donation program to further optimize potential of kidney paired donation to increase transplantation of O group and sensitized patients. This review assists in the development of similar programs in other developing countries. PMID:28507916

Past, present and future of kidney paired donation transplantation in India.

PubMed

Kute, Vivek B; Patel, Himanshu V; Shah, Pankaj R; Modi, Pranjal R; Shah, Veena R; Rizvi, Sayyed J; Pal, Bipin C; Modi, Manisha P; Shah, Priya S; Varyani, Umesh T; Wakhare, Pavan S; Shinde, Saiprasad G; Ghodela, Vijay A; Patel, Minaxi H; Trivedi, Varsha B; Trivedi, Hargovind L

2017-04-24

One third of healthy willing living kidney donors are rejected due to ABO blood group incompatibility and donor specific antibody. This increases pre-transplant dialysis duration leading to increased morbidity and mortality on the kidney transplantation waiting list. Over the last decade kidney paired donation is most rapidly increased source of living kidney donors. In a kidney transplantation program dominated by living donor kidney transplantation, kidney paired donation is a legal and valid alternative strategy to increase living donor kidney transplantation. This is more useful in countries with limited resources where ABO incompatible kidney transplantation or desensitization protocol is not feasible because of costs/infectious complications and deceased donor kidney transplantation is in initial stages. The matching allocation, ABO blood type imbalance, reciprocity, simultaneity, geography were the limitation for the expansion of kidney paired donation. Here we describe different successful ways to increase living donor kidney transplantation through kidney paired donation. Compatible pairs, domino chain, combination of kidney paired donation with desensitization or ABO incompatible transplantation, international kidney paired donation, non-simultaneous, extended, altruistic donor chain and list exchange are different ways to expand the donor pool. In absence of national kidney paired donation program, a dedicated kidney paired donation team will increase access to living donor kidney transplantation in individual centres with team work. Use of social networking sites to expand donor pool, HLA based national kidney paired donation program will increase quality and quantity of kidney paired donation transplantation. Transplant centres should remove the barriers to a broader implementation of multicentre, national kidney paired donation program to further optimize potential of kidney paired donation to increase transplantation of O group and sensitized patients. This review assists in the development of similar programs in other developing countries.

A national program for nondirected kidney donation from living unrelated donors: the Philippine experience.

PubMed

Manauis, M N; Pilar, K A; Lesaca, R; de Belen Uriarte, R; Danguilan, R; Ona, E

2008-09-01

The objectives of this study are to describe the mechanism of the program and to present initial donor outcome. This is a descriptive study evaluating the performance of a national program for nondirected kidney donation from living unrelated donors (LURDs) in the Philippines in its 3-year implementation. It explains the mechanism of the program and socioeconomic and clinical profiling of donors. Frequencies and percentages were used to measure donor demographic data, medical follow-up compliance rate, and employment predonation and postdonation. Diagnostic laboratory criteria were required to show donor clinical profiles. In 2002, the local Health Department issued an administrative order to create a National Transplant Ethics Committee (NTEC) to address issues of rampant organ sale and donor exploitation. It also set guidelines and intended to oversee transplantation from LURDs. Salient points to the program are as follows: (1) prohibition of sale; (2) accreditation of transplantation centers; (3) enrollment of waitlisted patients in both deceased donor and nondirected LURD program; (4) ethics committee evaluation of LURDs; (5) creation of a national kidney transplant wait list and live donor registry allowing centralized, nondirected kidney allocation; (6) 10% cap on allocation to foreigners; (7) creation of a kidney donor monitoring unit with free 10-year annual medical follow-up for feedback evaluation on donor outcome; and (8) allowance of gratitudinal gifts such as health and life insurance, reimbursement for lost income, educational plan, and job placement to LURDs run by a foundation. From 2004 to 2006, 695 potential donors enrolled; 97 were accepted and deemed medically fit to donate. The remaining 598 were rejected due to demand for outright sale (103), medical unsuitability (77), disapproval by the Ethics Committee (12), and retracted consent (406). Of the 97 qualified donors, 79 had donated, 9 were being evaluated, and 9 await allocation at the end of 2006. Donor demographics show the following: 54% (381) single, 77% (538) males, and 70% (488) aged 21-40 years old. Sixty-eight of 79 became small-scale entrepreneurs postdonation. Also, 53% (42 of 79) complied with medical follow-up requirements. Mean serum creatinine level at 6 months, 1 years, and 2 years were 1.3, 1.33, and 1.05 mg/dL, respectively. Two donors had trace protein and 1 had (+1) protein. The majority of the donors are single males, aged 21-40 years with blue collar jobs. Major reasons for dropouts are retracted consent and medical unsuitability. Donors have improved socioeconomic status. In this study, 53% complied with expected medical follow-up, showing mean serum creatinine within normal range. Proteinuria appeared in 2 of 79 donors. This regulated approach provides a rational, accessible, and equitable donor allocation program. It safeguards the rights of donors and avoids donor exploitation and proliferation of unregulated organ sale. Data collection on their postoperative renal function will show long-term outcome of kidney donation from live donors.

HLA AND CROSS·REACTIVE ANTIGEN GROUP MATCHING FOR CADAVER KIDNEY ALLOCATION1

PubMed Central

Starzl, Thomas E.; Eliasziw, Michael; Gjertson, David; Terasaki, Paul I.; Fung, John J.; Trucco, Massimo; Martell, Joan; McMichael, John; Scantlebury, Velma; Shapiro, Ron; Donner, Allan

2010-01-01

Background Allocation of cadaver kidneys by graded human leukocyte antigen (HLA) compatibility scoring arguably has had little effect on overall survival while prejudicing the transplant candidacy of African-American and other hard to match populations. Consequently, matching has been proposed of deduced amino acid residues of the individual HLA molecules shared by cross-reactive antigen groups (CREGs). We have examined the circumstances under which compatibility with either method impacted graft survival. Methods Using Cox proportional hazards regression modeling, we studied the relationship between levels of conventional HLA mismatch and other donor and recipient factors on primary cadaver kidney survival between 1981 and 1995 at the University of Pittsburgh (n=1,780) and in the United Network for Organ Sharing (UNOS) Scientific Registry during 1991–1995 (n=31,291). The results were compared with those obtained by the matching of amino acid residues that identified CREG-compatible cases with as many as four (but not five and six) HLA mismatches. Results With more than one HLA mismatch (>85% of patients in both series), most of the survival advantage of a zero mismatch was lost. None of the HLA loci were “weak.” In the UNOS (but not Pittsburgh) category of one-HLA mismatch (n=1334), a subgroup of CREG-matched recipients (35.3%) had better graft survival than the remaining 64.7%, who were CREG-mismatched. There was no advantage of a CREG match in the two- to four-HLA incompatibility tiers. Better graft survival with tacrolimus was observed in both the Pittsburgh and UNOS series. Conclusions Obligatory national sharing of cadaver kidneys is justifiable only for zero-HLA-mismatched kidneys. The potential value of CREG matching observed in the one-HLA-mismatched recipients of the UNOS (but not the Pittsburgh) experience deserves further study. PMID:9381546

Dual Kidney Transplantation: Evaluation of Recipient Selection Criteria at Niguarda Hospital.

PubMed

Mariani, A; Ferla, F; De Carlis, R; Rossetti, O; Covucci, E; Tripepi, M; Concone, G; Lauterio, A; Mangoni, I; De Carlis, L

2016-03-01

Dual kidney transplantation (DKT) is a largely accepted strategy to enlarge the donor pool. Niguarda Hospital started this program in December 2010, and 38 DKT have been performed. In our series, we included recipients older than those in the other series published in literature. The aim of this study was to know if our recipient selection criteria for DKT are safe. We reviewed our data base of DKT and analyzed recipients' medical history, surgical technique, post-operative complications, graft survival, morbidity, and mortality. We then compared our results with the literature. From December 2010 to April 2015, 38 DKT were performed in Niguarda Hospital. Delayed graft function was present in 21 recipients. Explantation of both kidneys was performed in 1 patient and explantation of 1 kidney in 6 patients. Post-operative complications were present in 8 patients. Five patients returned to hemodialysis after DKT. One recipient died of medical post-operative sepsis. The mean follow-up was 24 months. Graft survival and patient survival were 86.84% and 97.93%, respectively. Compared with the literature, our series had similar mortality and morbidity rates, even if recipients' age was higher than in other series. The strategy of DKT allocation in elderly recipients is safe. Further studies have to be performed to optimized selection of the recipients for DKT not to disadvantage younger patients in the transplant waiting list and to improve the technique of organ evaluation and preservation to refine graft allocation. Copyright © 2016 Elsevier Inc. All rights reserved.

Differences in access to kidney transplantation between Hispanic and non-Hispanic whites by geographic location in the United States.

PubMed

Arce, Cristina M; Goldstein, Benjamin A; Mitani, Aya A; Lenihan, Colin R; Winkelmayer, Wolfgang C

2013-12-01

Hispanic patients undergoing chronic dialysis are less likely to receive a kidney transplant compared with non-Hispanic whites. This study sought to elucidate disparities in the path to receipt of a deceased donor transplant between Hispanic and non-Hispanic whites. Using the US Renal Data System, 417,801 Caucasians who initiated dialysis between January 1, 1995 and December 31, 2007 with follow-up through 2008 were identified. This study investigated time from first dialysis to first kidney transplantation, time from first dialysis to waitlisting, and time from waitlisting to kidney transplantation. Multivariable Cox regression estimated cause-specific hazard ratios (HRCS) and subdistribution (competing risk) hazard ratios (HRSD) for Hispanics versus non-Hispanic whites. Hispanics experienced lower adjusted rates of deceased donor kidney transplantation than non-Hispanic whites (HRCS, 0.77; 95% confidence interval [95% CI], 0.75 to 0.80) measured from dialysis initiation. No meaningful differences were found in time from dialysis initiation to placement on the transplant waitlist. Once waitlisted, Hispanics had lower adjusted rates of deceased donor kidney transplantation (HRCS, 0.66; 95% CI, 0.64 to 0.68), and the association attenuated once accounting for competing risks (HRSD, 0.79; 95% CI, 0.77 to 0.81). Additionally controlling for blood type and organ procurement organization further reduced the disparity (HRSD, 0.99; 95% CI, 0.96 to 1.02). After accounting for geographic location and controlling for competing risks (e.g., Hispanic survival advantage), the disparity in access to deceased donor transplantation was markedly attenuated among Hispanics compared with non-Hispanic whites. To overcome the geographic disparities that Hispanics encounter in the path to transplantation, organ allocation policy revisions are needed to improve donor organ equity.

Strong human leukocyte antigen matching effect in nonsensitized kidney recipients with high pretransplant soluble CD30.

PubMed

Süsal, Caner; Pelzl, Steffen; Opelz, Gerhard

2003-10-27

The influence of human leukocyte antigen (HLA) matching on graft survival is greater in patients with preformed lymphocytotoxic antibodies than in nonsensitized patients. Pretransplant serum soluble CD30 (sCD30) affects graft outcome independently of presensitization status. The impact of HLA compatibility on kidney transplant survival was analyzed in 3980 nonsensitized first cadaveric kidney recipients in relation to the pretransplant serum sCD30 content. Although HLA compatibility influenced graft outcome only marginally in nonsensitized recipients with low sCD30 (at 3 years: P=0.0095; at 5 years: P=0.1033), a strong HLA matching effect was observed in nonsensitized recipients with high sCD30 (at 3 years: P<0.0001; at 5 years: P=0.0001). Nonsensitized patients with high pretransplant sCD30 benefit from an HLA well-matched kidney. Patients should be tested for sCD30 while on the waiting list for a kidney transplant, and HLA well-matched kidneys should be allocated to patients with high sCD30.

Should pediatric patients wait for HLA-DR-matched renal transplants?

PubMed

Gritsch, H A; Veale, J L; Leichtman, A B; Guidinger, M K; Magee, J C; McDonald, R A; Harmon, W E; Delmonico, F L; Ettenger, R B; Cecka, J M

2008-10-01

Graft survival rates from deceased donors aged 35 years or less among all primary pediatric kidney transplant recipients in the United States between 1996 and 2004 were retrospectively examined to determine the effect of HLA-DR mismatches on graft survival. Zero HLA-DR-mismatched kidneys had statistically comparable 5-year graft survival (71%), to 1-DR-mismatched kidneys (69%) and 2-DR-mismatched kidneys (71%). When compared to donors less than 35 years of age, the relative rate of allograft failure was 1.32 (p = 0.0326) for donor age greater than or equal to age 35. There was no statistical increase in the odds of developing a panel-reactive antibody (PRA) greater than 30% at the time of second waitlisting, based upon the degree of HLA-A, -B or -DR mismatch of the first transplant, nor was there a 'dose effect' when more HLA antigens were mismatched between the donor and recipient. Therefore, pediatric transplant programs should utilize the recently implemented Organ Procurement and Transplantation Network's (OPTN)allocation policy, which prioritizes pediatric recipients to receive kidneys from deceased donors less than 35 years of age, and should not turn down such kidney offers to wait for a better HLA-DR-matched kidney.

Questions and Answers for Transplant Candidates about Kidney Allocation Policy

MedlinePlus

... harder to find a donor with type B blood. Donors with blood type A generally can’t donate to a ... for type B patients. Since blood type A donors are more common than blood type B donors, more offers should be available ...

Increasing access to kidney transplantation in countries with limited resources: the Indian experience with kidney paired donation.

PubMed

Kute, Vivek B; Vanikar, Aruna V; Shah, Pankaj R; Gumber, Manoj R; Patel, Himanshu V; Engineer, Divyesh P; Modi, Pranjal R; Shah, Veena R; Trivedi, Hargovind L

2014-10-01

According to the Indian chronic kidney disease registry, in 2010 only 2% of end stage kidney disease patients were managed with kidney transplantation, 37% were managed with dialysis and 61% were treated conservatively without renal replacement therapy. In countries like India, where a well-organized deceased donor kidney transplantation program is not available, living donor kidney transplantation is the major source of organs for kidney transplantation. The most common reason to decline a donor for directed living donation is ABO incompatibility, which eliminates up to one third of the potential living donor pool. Because access to transplantation with human leukocyte antigen (HLA)-desensitization protocols and ABO incompatible transplantation is very limited due to high costs and increased risk of infections from more intense immunosuppression, kidney paired donation (KPD) promises hope to a growing number of end stage kidney disease patients. KPD is a rapidly growing and cost-effective living donor kidney transplantation strategy for patients who are incompatible with their healthy, willing living donor. In principle, KPD is feasible for any centre that performs living donor kidney transplantation. In transplant centres with a large living donor kidney transplantation program KPD does not require extra infrastructure, decreases waiting time, avoids transplant tourism and prevents commercial trafficking. Although KPD is still underutilized in India, it has been performed more frequently in recent times. To substantially increase donor pool and transplant rates, transplant centres should work together towards a national KPD program and frame a uniform acceptable allocation policy. © 2014 Asian Pacific Society of Nephrology.

Utility in Treating Kidney Failure in End-Stage Liver Disease With Simultaneous Liver-Kidney Transplantation.

PubMed

Cheng, Xingxing S; Stedman, Margaret R; Chertow, Glenn M; Kim, W Ray; Tan, Jane C

2017-05-01

Simultaneous liver-kidney (SLK) transplantation plays an important role in treating kidney failure in patients with end-stage liver disease. It used 5% of deceased donor kidney transplanted in 2015. We evaluated the utility, defined as posttransplant kidney allograft lifespan, of this practice. Using data from the Scientific Registry of Transplant Recipients, we compared outcomes for all SLK transplants between January 1, 1995, and December 3, 2014, to their donor-matched kidney used in kidney-alone (Ki) or simultaneous pancreas kidney (SPK) transplants. Primary outcome was kidney allograft lifespan, defined as the time free from death or allograft failure. Secondary outcomes included death and death-censored allograft failure. We adjusted all analyses for donor, transplant, and recipient factors. The adjusted 10-year mean kidney allograft lifespan was higher in Ki/SPK compared with SLK transplants by 0.99 years in the Model for End-stage Liver Disease era and 1.71 years in the pre-Model for End-stage Liver Disease era. Death was higher in SLK recipients relative to Ki/SPK recipients: 10-year cumulative incidences 0.36 (95% confident interval 0.33-0.38) versus 0.19 (95% confident interval 0.17-0.21). SLK transplantation exemplifies the trade-off between the principles of utility and medical urgency. With each SLK transplantation, about 1 year of allograft lifespan is traded so that sicker patients, that is, SLK transplant recipients, are afforded access to the organ. These data provide a basis against which benefits derived from urgency-based allocation can be measured.

Utility in Treating Kidney Failure in End-Stage Liver Disease With Simultaneous Liver-Kidney Transplantation

PubMed Central

Cheng, Xingxing S.; Stedman, Margaret R.; Chertow, Glenn M.; Kim, W. Ray; Tan, Jane C.

2017-01-01

Background Simultaneous liver-kidney (SLK) transplantation plays an important role in treating kidney failure in patients with end-stage liver disease. It used 5% of deceased donor kidney transplanted in 2015. We evaluated the utility, defined as posttransplant kidney allograft lifespan, of this practice. Methods Using data from the Scientific Registry of Transplant Recipients, we compared outcomes for all SLK transplants between January 1, 1995, and December 3, 2014, to their donor-matched kidney used in kidney-alone (Ki) or simultaneous pancreas kidney (SPK) transplants. Primary outcome was kidney allograft lifespan, defined as the time free from death or allograft failure. Secondary outcomes included death and death-censored allograft failure. We adjusted all analyses for donor, transplant, and recipient factors. Results The adjusted 10-year mean kidney allograft lifespan was higher in Ki/SPK compared with SLK transplants by 0.99 years in the Model for End-stage Liver Disease era and 1.71 years in the pre-Model for End-stage Liver Disease era. Death was higher in SLK recipients relative to Ki/SPK recipients: 10-year cumulative incidences 0.36 (95% confident interval 0.33-0.38) versus 0.19 (95% confident interval 0.17-0.21). Conclusions SLK transplantation exemplifies the trade-off between the principles of utility and medical urgency. With each SLK transplantation, about 1 year of allograft lifespan is traded so that sicker patients, that is, SLK transplant recipients, are afforded access to the organ. These data provide a basis against which benefits derived from urgency-based allocation can be measured. PMID:28437790

Long-term results of biopsy-guided selection and allocation of kidneys from older donors in older recipients.

PubMed

Fernández-Lorente, L; Riera, L; Bestard, O; Carrera, M; Gomà, M; Porta, N; Torras, J; Melilli, E; Gil-Vernet, S; Grinyó, J M; Cruzado, J M

2012-10-01

In our old-for-old program, we discard or allocate older extended criteria donor kidneys to single (SKT) or dual kidney transplantation (DKT) depending on histological Remuzzi's score in recipients older than 60 years. Here, we analyze the long-term results of this program and try to identify independent predictors of patient and graft survival. Between December 1996 and January 2008, we performed 115 SKT and 88 DKT. Discard rate was 15%. Acute rejection incidence was higher in SKT than in DKT (22.6% vs. 11.4%, p = 0.04). Renal function was better in DKT than in SKT up to 5 years after transplantation. Surgical complications were frequent in DKT. Ten-year cumulative graft survival was significantly lower in the SKT group (31% vs. 53%, p = 0.03). In SKT, histological score 4 provided similar graft survival than 3 or less, whereas in DKT score 4, 5 or 6 displayed similar outcome. Finally, independent predictors of graft survival were history of major adverse cardiac event and 1-year serum creatinine, rather than SKT or DKT. In conclusion, this biopsy-guided old-for-old strategy resulted in acceptable long-term graft survival. Our results suggest that DKT should be considered for scores of 5 or 6 only. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

Renal dysfunction in early adulthood following birth asphyxia in male spiny mice, and its amelioration by maternal creatine supplementation during pregnancy.

PubMed

Ellery, Stacey J; LaRosa, Domenic A; Cullen-McEwen, Luise A; Brown, Russell D; Snow, Rod J; Walker, David W; Kett, Michelle M; Dickinson, Hayley

2017-04-01

Acute kidney injury affects ~70% of asphyxiated newborns, and increases their risk of developing chronic kidney disease later in life. Acute kidney injury is driven by renal oxygen deprivation during asphyxia, thus we hypothesized that creatine administered antenatally would protect the kidney from the long-term effects of birth asphyxia. Pregnant spiny mice were fed standard chow or chow supplemented with 5% creatine from 20-d gestation (midgestation). One day prior to term (37-d gestation), pups were delivered by caesarean or subjected to intrauterine asphyxia. Litters were allocated to one of two time-points. Kidneys were collected at 1 mo of age to estimate nephron number (stereology). Renal function (excretory profile and glomerular filtration rate) was measured at 3 mo of age, and kidneys then collected for assessment of glomerulosclerosis. Compared with controls, at 1 mo of age male (but not female) birth-asphyxia offspring had 20% fewer nephrons (P < 0.05). At 3 mo of age male birth-asphyxia offspring had 31% lower glomerular filtration rate (P < 0.05) and greater glomerular collagen IV content (P < 0.01). Antenatal creatine prevented these renal injuries arising from birth asphyxia. Maternal creatine supplementation during pregnancy may be an effective prophylactic to prevent birth asphyxia induced acute kidney injury and the emergence of chronic kidney disease.

Approach to the Highly Sensitized Kidney Transplant Candidate

PubMed Central

Vranic, Gayle M.

2016-01-01

For patients with ESRD, kidney transplant offers significant survival and quality-of-life advantages compared with dialysis. But for patients seeking transplant who are highly sensitized, wait times have traditionally been long and options limited. The approach to the highly sensitized candidate for kidney transplant has changed substantially over time owing to new advances in desensitization, options for paired donor exchange (PDE), and changes to the deceased-donor allocation system. Initial evaluation should focus on determining living-donor availability because a compatible living donor is always the best option. However, for most highly sensitized candidates this scenario is unlikely. For candidates with an incompatible donor, PDE can improve the prospects of finding a compatible living donor but for many highly sensitized patients the probability of finding a match in the relatively small pools of donors in PDE programs is limited. Desensitization of a living donor/recipient pair with low levels of incompatibility is another reasonable approach. But for pairs with high levels of pathologic HLA antibodies, outcomes after desensitization for the patient and allograft are less optimal. Determining the degree of sensitization by calculated panel-reactive antibody (cPRA) is critical in counseling the highly sensitized patient on expected wait times to deceased-donor transplant. For candidates with a high likelihood of finding a compatible deceased donor in a reasonable time frame, waiting for a kidney is a good strategy. For the candidate without a living donor and with a low probability of finding a deceased-donor match, desensitization on the waiting list can be considered. The approach to the highly sensitized kidney transplant candidate must be individualized and requires careful discussion among the transplant center, patient, and referring nephrologist. PMID:26915916

Single-center experience in double kidney transplantation.

PubMed

Fontana, I; Magoni Rossi, A; Gasloli, G; Santori, G; Giannone, A; Bertocchi, M; Piaggio, F; Bocci, E; Valente, Umberto

2010-05-01

Use of organs from marginal donors for transplantation is a current strategy to expand the organ donor pool. Its efficacy is universally accepted among data from multicenter studies. Herein, we have reviewed outcomes of double kidney transplantation (DKT) over an 9-year experience in our center. The aim of this study was to evaluate possible important differences between a monocenter versus multicenter studies. Between 1999 and 2008, we performed 59 DKT. Recipient mean age was 63 +/- 5 years. Mean HLA-A, -B, and -DR mismatches were 3.69 +/- 0.922. Donor mean age was 69 +/- 7 years and mean creatinine clearance was 69.8 +/- 30.8 mL/min. Proteinuria was detected in three donors (5%). Mean cold ischemia and warm ischemia times were 1130 +/- 216 and 48 +/- 11 minutes, respectively. The right and left kidney scores were 4.18 +/- 2 and 4.21 +/- 2, respectively. Thirty patients (51%) displayed good postoperative renal function; 22 (37%), acute tubular necrosis with postoperative dialysis; 3 (5%), acute rejection episodes; 4 (7%), single-graft transplantectomy due to vascular thrombosis; 1 (2%), a retransplantation; 5 (8%), a lymphocele; 3 (5%) vescicoureteral reflux or stenosis requiring surgical correction. Cytomegalovirus infection was detected in five patients (8%). In three patients (5%) displayed de novo neoplasia. Three patients showed chronic rejection (5%), whereas we observed a cyclosporine-related toxicity in 7 (12%). Nine patients (15%) developed iatrogenic diabetes. Patient and graft survivals after 3 years from DKT were 93% and 86.3%, respectively. In this study, we applied successfully a widespread score to allocate organs to single kidney transplantation or DKT. In our experience, the score is suitable for the organ allocation but it may be overprotective, excluding potentially suitable organs for a single transplantation. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Changes in the organ procurement system in South Korea: effects on brain-dead donor numbers.

PubMed

Lee, S D; Kim, J H

2009-11-01

In Korea, the Organ Transplantation Act came into effect in 2000, establishing the Korean Network for Organ Sharing (KONOS) with centralized authority for organ procurement as well as for approval of donors and recipients to ensure fair organ allocation. However, the number of brain-dead donors decreased sharply, and the organ allocation system proved inefficient. The government revised the Organ Transplantation Act in August 2002, introducing an incentive system. If a transplantation hospital formed a Committee for Brain Death Evaluation and a Hospital Organ Procurement Organization, it could receive a kidney from a brain dead-donor as an incentive to foster organ procurement regardless of the KONOS wait list. The government also launched a pilot brain-dead donor registry program to strengthen Hospital Organ Procurement Organization activity. If local hospitals collaborated with specialized hospitals in organ procurement, local hospitals obtained financial incentives. But because the organ shortage problem has not been resolved, the government has proposed four initiatives: first, broadening the incentive system, which makes it possible to give each specialized hospital a choice of one of eight organs from each donor as an incentive; second, development of an Independent Organ Procurement Organization; third introduction of an opt-out system; and last, improvement of the Committee for Brain Death Evaluation system. It is uncertain which initiatives will be adopted, but changes in organ procurement systems are nonetheless considered a key to solve the organ shortage problem in Korea.

Differences in Access to Kidney Transplantation between Hispanic and Non-Hispanic Whites by Geographic Location in the United States

PubMed Central

Goldstein, Benjamin A.; Mitani, Aya A.; Lenihan, Colin R.; Winkelmayer, Wolfgang C.

2013-01-01

Summary Background and objectives Hispanic patients undergoing chronic dialysis are less likely to receive a kidney transplant compared with non-Hispanic whites. This study sought to elucidate disparities in the path to receipt of a deceased donor transplant between Hispanic and non-Hispanic whites. Design, setting, participants, & measurements Using the US Renal Data System, 417,801 Caucasians who initiated dialysis between January 1, 1995 and December 31, 2007 with follow-up through 2008 were identified. This study investigated time from first dialysis to first kidney transplantation, time from first dialysis to waitlisting, and time from waitlisting to kidney transplantation. Multivariable Cox regression estimated cause-specific hazard ratios (HRCS) and subdistribution (competing risk) hazard ratios (HRSD) for Hispanics versus non-Hispanic whites. Results Hispanics experienced lower adjusted rates of deceased donor kidney transplantation than non-Hispanic whites (HRCS, 0.77; 95% confidence interval [95% CI], 0.75 to 0.80) measured from dialysis initiation. No meaningful differences were found in time from dialysis initiation to placement on the transplant waitlist. Once waitlisted, Hispanics had lower adjusted rates of deceased donor kidney transplantation (HRCS, 0.66; 95% CI, 0.64 to 0.68), and the association attenuated once accounting for competing risks (HRSD, 0.79; 95% CI, 0.77 to 0.81). Additionally controlling for blood type and organ procurement organization further reduced the disparity (HRSD, 0.99; 95% CI, 0.96 to 1.02). Conclusions After accounting for geographic location and controlling for competing risks (e.g., Hispanic survival advantage), the disparity in access to deceased donor transplantation was markedly attenuated among Hispanics compared with non-Hispanic whites. To overcome the geographic disparities that Hispanics encounter in the path to transplantation, organ allocation policy revisions are needed to improve donor organ equity. PMID:24115195

Chronic Kidney Disease and Related Long-term Complications Following Liver Transplantation

PubMed Central

Sharma, Pratima; Bari, Khurram

2015-01-01

Liver transplantation (LT) is the standard of care for patients with decompensated cirrhosis. LT recipients have excellent short-term and long-term outcomes including patient and graft survival. Since the adoption of model for end-stage liver disease (MELD) - based allocation policy, the incidence of post-transplant end stage renal disease has risen significantly. Occurrence of stage 4 chronic kidney disease and end stage renal disease substantially increase the risk of post-transplant deaths. Since majority of late post-transplant mortality is due to non-hepatic post-transplant comorbidities, personalized care directed towards risk factor modification may further improve post-transplant survival. PMID:26311603

Liver and Kidney Transplantation: A Half-Century Historical Perspective.

PubMed

Sass, David A; Doyle, Alden M

2016-05-01

This article describes the evolution of solid organ kidney and liver transplantation and expounds on the challenges and successes that the early transplant researchers and clinicians encountered. The article highlights the surgical pioneers, delves into the milestones of enhanced immunosuppression protocols, discusses key federal legislative and policy changes, and expounds on the ongoing disparities of organ supply and demand and the need for extended criteria and live donor organs to combat these shortages. Finally, recent changes in organ allocation and distribution policies are discussed. The authors also spotlight novel interventions that will further revolutionize abdominal transplantation in the next 50 years. Copyright © 2016 Elsevier Inc. All rights reserved.

Glutathione S-transferase iso-enzymes in perfusate from pumped kidneys are associated with delayed graft function

PubMed Central

Hall, Isaac E.; Bhangoo, Ronik S.; Reese, Peter P.; Doshi, Mona D.; Weng, Francis L.; Hong, Kwangik; Lin, Haiqun; Han, Gang; Hasz, Rick D.; Goldstein, Michael J.; Schröppel, Bernd; Parikh, Chirag R.

2014-01-01

Accurate and reliable assessment tools are needed in transplantation. The objective of this prospective, multicenter study was to determine the associations of the alpha and pi iso-enzymes of glutathione S-transferase (GST), measured from perfusate solution at the start and end (base and post) of kidney allograft machine perfusion, with subsequent delayed graft function (DGF). We also compared GST iso-enzyme perfusate levels from discarded versus transplanted kidneys. A total of 428 kidneys were linked to outcomes as recorded by the United Network of Organ Sharing. DGF, defined as any dialysis in the first week of transplant, occurred in 141 recipients (32%). Alpha and pi-GST levels significantly increased during machine perfusion. The adjusted relative risks (95% confidence interval) of DGF with each log-unit increase in base and post pi-GST were 1.14 (1.0-1.28) and 1.33 (1.02-1.72), respectively. Alpha-GST was not independently associated with DGF. There were no significant differences in GST values between discarded and transplanted kidneys, though renal resistance was significantly higher in discarded kidneys. We found pi-GST at the end of machine perfusion to be independently associated with DGF. Further studies should elucidate the utility of GST for identifying injured kidneys with regard to organ allocation, discard and recipient management decisions. PMID:24612768

Zero-Time Renal Transplant Biopsies: A Comprehensive Review.

PubMed

Naesens, Maarten

2016-07-01

Zero-time kidney biopsies, obtained at time of transplantation, are performed in many transplant centers worldwide. Decisions on kidney discard, kidney allocation, and choice of peritransplant and posttransplant treatment are sometimes based on the histological information obtained from these biopsies. This comprehensive review evaluates the practical considerations of performing zero-time biopsies, the predictive performance of zero-time histology and composite histological scores, and the clinical utility of these biopsies. The predictive performance of individual histological lesions and of composite scores for posttransplant outcome is at best moderate. No single histological lesion or composite score is sufficiently robust to be included in algorithms for kidney discard. Dual kidney transplantation has been based on histological assessment of zero-time biopsies and improves outcome in individual patients, but the waitlist effects of this strategy remain obscure. Zero-time biopsies are valuable for clinical and translational research purposes, providing insight in risk factors for posttransplant events, and as baseline for comparison with posttransplant histology. The molecular phenotype of zero-time biopsies yields novel therapeutic targets for improvement of donor selection, peritransplant management and kidney preservation. It remains however highly unclear whether the molecular expression variation in zero-time biopsies could become a better predictor for posttransplant outcome than donor/recipient baseline demographic factors.

Transplantation rates for living- but not deceased-donor kidneys vary with socioeconomic status in Australia.

PubMed

Grace, Blair S; Clayton, Philip A; Cass, Alan; McDonald, Stephen P

2013-01-01

Socioeconomic disadvantage has been linked to reduced access to kidney transplantation. To understand and address potential barriers to transplantation, we used the Australia and New Zealand Dialysis and Transplant Registry and examined primary kidney-only transplantation among adult non-Indigenous patients who commenced chronic renal replacement therapy in Australia during 2000-2010. Socioeconomic status was derived from residential postcodes using standard indices. Among the 21,190 patients who commenced renal replacement therapy, 4105 received a kidney transplant (2058 from living donors (660 preemptive) or 2047 from deceased donors) by the end of 2010. Compared with the most socioeconomic disadvantaged quartile, patients from the most advantaged quartile were more likely to receive a preemptive transplant (relative rate 1.93), and more likely to receive a living-donor kidney (adjusted subhazard ratio 1.34) after commencing dialysis. Socioeconomic status was not associated with deceased-donor transplantation. Thus, the association between socioeconomic status and living- but not deceased-donor transplantation suggests that potential donors (rather than recipients) from disadvantaged areas may face barriers to donation. Although the deceased-donor organ allocation process appears essentially equitable, it differs between Australian states.

Development of Organ-Specific Donor Risk Indices

PubMed Central

Akkina, Sanjeev K.; Asrani, Sumeet K.; Peng, Yi; Stock, Peter; Kim, Ray; Israni, Ajay K.

2012-01-01

Due to the shortage of deceased donor organs, transplant centers accept organs from marginal deceased donors, including older donors. Organ-specific donor risk indices have been developed to predict graft survival using various combinations of donor and recipient characteristics. We will review the kidney donor risk index (KDRI) and liver donor risk index (LDRI) and compare and contrast their strengths, limitations, and potential uses. The Kidney Donor Risk Index has a potential role in developing new kidney allocation algorithms. The Liver Donor Risk Index allows for greater appreciation of the importance of donor factors, particularly for hepatitis C-positive recipients; as the donor risk index increases, rates of allograft and patient survival among these recipients decrease disproportionately. Use of livers with high donor risk index is associated with increased hospital costs independent of recipient risk factors, and transplanting livers with high donor risk index into patients with Model for End-Stage Liver Disease scores < 15 is associated with lower allograft survival; use of the Liver Donor Risk Index has limited this practice. Significant regional variation in donor quality, as measured by the Liver Donor Risk Index, remains in the United States. We also review other potential indices for liver transplant, including donor-recipient matching and the retransplant donor risk index. While substantial progress has been made in developing donor risk indices to objectively assess donor variables that affect transplant outcomes, continued efforts are warranted to improve these indices to enhance organ allocation policies and optimize allograft survival. PMID:22287036

Kidney Transplantation From Donors with Hepatitis B

PubMed Central

Veroux, Massimiliano; Ardita, Vincenzo; Corona, Daniela; Giaquinta, Alessia; Ekser, Burcin; Sinagra, Nunziata; Zerbo, Domenico; Patanè, Marco; Gozzo, Cecilia; Veroux, Pierfrancesco

2016-01-01

The growing demand for organ donors to supply the increasing number of patients on kidney waiting lists has led most transplant centers to develop protocols that allow safe use of organs from donors with special clinical situations previously regarded as contraindications. Deceased donors with previous hepatitis B may be a safe resource to increase the donor pool even if there is still controversy among transplantation centers regarding the use of hepatitis B surface antigen-positive donors for renal transplantation. However, when allocated to serology-matched recipients, kidney transplantation from donors with hepatitis B may result in excellent short-term outcome. Many concerns may arise in the long-term outcome, and studies must address the evaluation of the progression of liver disease and the rate of reactivation of liver disease in the recipients. Accurate selection and matching of both donor and recipient and correct post-transplant management are needed to achieve satisfactory long-term outcomes. PMID:27123988

Sirolimus Associated with Tacrolimus at Low Doses in Elderly Kidney Transplant Patients: A Prospective Randomized Controlled Trial.

PubMed

Kojima, Cristiane Akemi; Nga, Hong Si; Takase, Henrique Mochida; Bravin, Ariane Moyses; Martinez Garcia, Márcia de Fátima Faraldo; Garcia, Paula Dalsoglio; Contti, Mariana Moraes; de Andrade, Luis Gustavo Modelli

2018-06-01

There is no consensus on the best immunosuppressive regimen for elderly renal transplant recipients. The objective of this study was to assess cytomegalovirus infection incidence and kidney transplant outcomes in elderly recipients treated with mammalian target of rapamycin inhibitors sirolimus/ tacrolimus at low doses compared with those receiving tacrolimus/mycophenolate sodium. In this single-center prospective randomized study (Trial Registration No. NCT02683291), kidney transplant recipients over 60 years of age were randomly allocated into 2 groups: tacrolimus-sirolimus (21 patients) and tacrolimus-mycophenolate (23 patients). Cytomegalovirus infection rate and patient survival, biopsy-proven acute rejection, and renal function at 12 months were assessed. Cytomegalovirus infection rate was higher in the mycophenolate group (60.9%) than in the sirolimus group (16.7%; P = .004). The rates of biopsy-proven acute rejection, patient survival, graft survival, and estimated glomerular filtration rate over 12 months did not significantly differ between groups. The incidence of cytomegalovirus infection was significantly lower in the sirolimus group. The use of tacrolimus combined with sirolimus in elderly kidney transplant recipients is safe.

Glutathione S-transferase iso-enzymes in perfusate from pumped kidneys are associated with delayed graft function.

PubMed

Hall, I E; Bhangoo, R S; Reese, P P; Doshi, M D; Weng, F L; Hong, K; Lin, H; Han, G; Hasz, R D; Goldstein, M J; Schröppel, B; Parikh, C R

2014-04-01

Accurate and reliable assessment tools are needed in transplantation. The objective of this prospective, multi-center study was to determine the associations of the alpha and pi iso-enzymes of glutathione S-transferase (GST), measured from perfusate solution at the start and end (base and post) of kidney allograft machine perfusion, with subsequent delayed graft function (DGF). We also compared GST iso-enzyme perfusate levels from discarded versus transplanted kidneys. A total of 428 kidneys were linked to outcomes as recorded by the United Network of Organ Sharing. DGF, defined as any dialysis in the first week of transplant, occurred in 141 recipients (32%). Alpha- and pi-GST levels significantly increased during machine perfusion. The adjusted relative risks (95% confidence interval) of DGF with each log-unit increase in base and post pi-GST were 1.14 (1.0-1.3) and 1.36 (1.1-1.8), respectively. Alpha-GST was not independently associated with DGF. There were no significant differences in GST values between discarded and transplanted kidneys, though renal resistance was significantly higher in discarded kidneys. We found pi-GST at the end of machine perfusion to be independently associated with DGF. Further studies should elucidate the utility of GST for identifying injured kidneys with regard to organ allocation, discard and recipient management decisions. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.

Evolutionary Nephrology.

PubMed

Chevalier, Robert L

2017-05-01

Progressive kidney disease follows nephron loss, hyperfiltration, and incomplete repair, a process described as "maladaptive." In the past 20 years, a new discipline has emerged that expands research horizons: evolutionary medicine. In contrast to physiologic (homeostatic) adaptation, evolutionary adaptation is the result of reproductive success that reflects natural selection. Evolutionary explanations for physiologically maladaptive responses can emerge from mismatch of the phenotype with environment or evolutionary tradeoffs. Evolutionary adaptation to a terrestrial environment resulted in a vulnerable energy-consuming renal tubule and a hypoxic, hyperosmolar microenvironment. Natural selection favors successful energy investment strategy: energy is allocated to maintenance of nephron integrity through reproductive years, but this declines with increasing senescence after ~40 years of age. Risk factors for chronic kidney disease include restricted fetal growth or preterm birth (life history tradeoff resulting in fewer nephrons), evolutionary selection for APOL1 mutations (that provide resistance to trypanosome infection, a tradeoff), and modern life experience (Western diet mismatch leading to diabetes and hypertension). Current advances in genomics, epigenetics, and developmental biology have revealed proximate causes of kidney disease, but attempts to slow kidney disease remain elusive. Evolutionary medicine provides a complementary approach by addressing ultimate causes of kidney disease. Marked variation in nephron number at birth, nephron heterogeneity, and changing susceptibility to kidney injury throughout life history are the result of evolutionary processes. Combined application of molecular genetics, evolutionary developmental biology (evo-devo), developmental programming and life history theory may yield new strategies for prevention and treatment of chronic kidney disease.

Hypothermic machine perfusion permits extended cold ischemia times with improved early graft function.

PubMed

Guy, Alison; McGrogan, Damian; Inston, Nicholas; Ready, Andrew

2015-04-01

The logistics of deceased-donor renal transplants are largely affected by cold ischemia time. However, to attain successful outcomes, other issues must be considered. Extending cold ischemia time to accommodate these issues would be valuable. We investigated the role of hypothermic machine perfusion to extend cold ischaemia time. Deceased-donor kidneys were allocated to a storage method, depending on predicted time to operation. Kidneys to be transplanted from 8:00 AM to 8:00 PM in the transplant room remained in static cold storage. If predicted operating time was out of hours, the kidney was transferred to hypothermic machine perfusion and transplanted at the earliest opportunity on the dedicated transplant list. There were 74 kidneys transplanted from hypothermic machine perfusion and 101 kidneys from static cold storage. Median cold ischemia time was 23.85 hours in the hypothermic machine perfusion group, compared with 13 hours in the static cold storage group (P ≤ .0001). There were 20 kidneys (27%) from hypothermic machine perfusion that had delayed graft function, compared with 47 kidneys (47%) in the static cold storage group (P = .012). There were no other significant differences in graft or postoperative complications. This study demonstrated that improved early graft outcomes can be achieved following longer cold ischemia time by using hypothermic machine perfusion rather than static cold storage. This effect is likely multifactorial including the inherent effects of hypothermic machine perfusion, improved recipient preparation, and possibly better perioperative conditions.

Apolipoprotein L1 gene variants in deceased organ donors are associated with renal allograft failure.

PubMed

Freedman, B I; Julian, B A; Pastan, S O; Israni, A K; Schladt, D; Gautreaux, M D; Hauptfeld, V; Bray, R A; Gebel, H M; Kirk, A D; Gaston, R S; Rogers, J; Farney, A C; Orlando, G; Stratta, R J; Mohan, S; Ma, L; Langefeld, C D; Hicks, P J; Palmer, N D; Adams, P L; Palanisamy, A; Reeves-Daniel, A M; Divers, J

2015-06-01

Apolipoprotein L1 gene (APOL1) nephropathy variants in African American deceased kidney donors were associated with shorter renal allograft survival in a prior single-center report. APOL1 G1 and G2 variants were genotyped in newly accrued DNA samples from African American deceased donors of kidneys recovered and/or transplanted in Alabama and North Carolina. APOL1 genotypes and allograft outcomes in subsequent transplants from 55 U.S. centers were linked, adjusting for age, sex and race/ethnicity of recipients, HLA match, cold ischemia time, panel reactive antibody levels, and donor type. For 221 transplantations from kidneys recovered in Alabama, there was a statistical trend toward shorter allograft survival in recipients of two-APOL1-nephropathy-variant kidneys (hazard ratio [HR] 2.71; p = 0.06). For all 675 kidneys transplanted from donors at both centers, APOL1 genotype (HR 2.26; p = 0.001) and African American recipient race/ethnicity (HR 1.60; p = 0.03) were associated with allograft failure. Kidneys from African American deceased donors with two APOL1 nephropathy variants reproducibly associate with higher risk for allograft failure after transplantation. These findings warrant consideration of rapidly genotyping deceased African American kidney donors for APOL1 risk variants at organ recovery and incorporation of results into allocation and informed-consent processes. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

The Risk of Transplant Failure With HLA Mismatch in First Adult Kidney Allografts 2: Living Donors, Summary, Guide

PubMed Central

Williams, Robert C.; Opelz, Gerhard; Weil, E. Jennifer; McGarvey, Chelsea J.; Chakkera, Harini A.

2017-01-01

Background Allografts from living donors survive longer than those from deceased donors but the role of HLA mismatching in living kidney donation is still in question. We examined the effect of HLA compatibility on kidney allograft survival from living donors by studying all first adult kidney transplants performed in the United States over 25 years. Methods Using the United Network for Organ Sharing data, we identified first kidney transplants between October 1, 1987, and December 31, 2013. Recipients were classified by their number of HLA mismatches and stratified by donor origin. Cox multivariate regression analyses adjusting for recipient and donor transplant characteristics were performed to determine impact of HLA compatibility on kidney allograft survival for all living donors and for living related and living unrelated subsets. Results There were 66 596 first adult transplants from living donors with 348 960 years of follow-up. We found a linear relationship between HLA mismatch and allograft survival. In adjusted analyses, among all living donors, 1 mismatch conferred a 44% higher risk, whereas 6 mismatches conferred a twofold higher risk of allograft failure. When using 0-mismatched full siblings as a reference, living-donor kidneys reduce the hazard of failure by approximately 34% when compared with deceased donors. Twenty-five years of transplant experience, stratified by donor source, was summarized and presented as a guide for allocation. Conclusions These data reinforce the importance of optimizing HLA matching to further improve survival in first adult kidney allografts in the future, especially in living unrelated donations, when possible. PMID:28573187

The Risk of Transplant Failure With HLA Mismatch in First Adult Kidney Allografts 2: Living Donors, Summary, Guide.

PubMed

Williams, Robert C; Opelz, Gerhard; Weil, E Jennifer; McGarvey, Chelsea J; Chakkera, Harini A

2017-05-01

Allografts from living donors survive longer than those from deceased donors but the role of HLA mismatching in living kidney donation is still in question. We examined the effect of HLA compatibility on kidney allograft survival from living donors by studying all first adult kidney transplants performed in the United States over 25 years. Using the United Network for Organ Sharing data, we identified first kidney transplants between October 1, 1987, and December 31, 2013. Recipients were classified by their number of HLA mismatches and stratified by donor origin. Cox multivariate regression analyses adjusting for recipient and donor transplant characteristics were performed to determine impact of HLA compatibility on kidney allograft survival for all living donors and for living related and living unrelated subsets. There were 66 596 first adult transplants from living donors with 348 960 years of follow-up. We found a linear relationship between HLA mismatch and allograft survival. In adjusted analyses, among all living donors, 1 mismatch conferred a 44% higher risk, whereas 6 mismatches conferred a twofold higher risk of allograft failure. When using 0-mismatched full siblings as a reference, living-donor kidneys reduce the hazard of failure by approximately 34% when compared with deceased donors. Twenty-five years of transplant experience, stratified by donor source, was summarized and presented as a guide for allocation. These data reinforce the importance of optimizing HLA matching to further improve survival in first adult kidney allografts in the future, especially in living unrelated donations, when possible.

The risk of cancer in recipients of living-donor, standard and expanded criteria deceased donor kidney transplants: a registry analysis.

PubMed

Ma, Maggie K M; Lim, Wai H; Turner, Robin M; Chapman, Jeremy R; Craig, Jonathan C; Wong, Germaine

2014-12-27

Kidneys from expanded criteria deceased donors may elicit a strong inflammatory response, predisposing recipients to an increased risk of cancer after transplantation. We aimed to determine the association between donor types and cancer risk after kidney transplantation. Using the Australian and New Zealand Dialysis and Transplant Registry, we assessed the association between different donor types (living donor, standard, and expanded criteria deceased donors) and the risk of cancer after kidney transplantation using adjusted Cox proportional hazard and competing risk models. Over a median follow-up period of 4.4 years in 7,040 patients (34,684 patient-years), 468 patients (6.6%) developed cancer. The overall risks for cancer were 1,080, 1,444, and 2,018 per 100,000 patient-years for recipients of living donor, standard, and expanded criteria deceased donor kidneys, respectively. Compared to recipients of living-donor kidneys, recipients of expanded criteria deceased donor kidneys were at an increased risk of cancer (adjusted hazard ratio [HR], 1.52; 95% confidence interval [95% CI], 1.15-2.02; P = 0.004), particularly for genitourinary cancer (adjusted HR, 1.79; 95% CI, 1.03-3.10; P = 0.038) and post-transplant lymphoproliferative disease (adjusted HR, 2.72; 95% CI, 1.38-5.37; P = 0.004). Recipients of expanded criteria deceased donor kidneys are at substantially increased risk of cancer, especially cancers with a viral etiology. Allocation of expanded criteria deceased donor kidneys to potential recipients should balance the harms, such as the excess risk of cancer against the survival gains and quality-of-life benefits associated with transplantation.

HLA-A, -B, and -DR zero-mismatched kidneys shipped to the University of Wisconsin, Madison, 1993-2006: superior graft survival despite longer preservation time.

PubMed

Burlingham, William J; Muñoz del Rio, Alejandro; Lorentzen, David; Sollinger, Hans W; Pirsch, John D; Jankowska-Gan, Ewa; D'Alessandro, Anthony

2010-08-15

To determine the impact at a single center of the United Network for Organ Sharing-mandated sharing program for human leukocyte antigen (HLA)-A/-B/-DR 0-mismatched (0MM) kidneys, we analyzed the results of 264 kidney transplants from 0MM distant donors between 1993 and 2006, with a follow-up through January 31, 2007. We compared these results with that of concurrent kidneys transplanted from HLA more than 0MM local donors and with shipped more than 0MM kidneys from "payback" donors. Despite a significantly longer preservation time, we found an 11% increase in 8-year graft survival (63% vs. 52%; P<0.003) of 0MM shipped versus locally procured, >0MM donor kidneys. Graft survival of 0MM shipped kidneys at 8 years was significantly better in nonsensitized (<20% panel reactive antibodies; 68% vs. 55%; P<0.0005) but not in sensitized (>or=20% panel reactive antibodies) recipients, who showed an early (2 years) but short-lived benefit. The benefit of receiving a HLA-A, -B, and -DR 0MM shipped kidney remained strong and statistically significant (0.71 relative risk of graft loss vs. local; P<0.02) when adjusted for 22 potentially confounding variables in a Cox proportional hazards analysis. The recent change in United Network for Organ Sharing policy restricting mandated sharing of 0MM kidneys to sensitized and pediatric recipients will give greater flexibility to the local organ procurement organization in allocating organs. However, the survival benefit to nonsensitized patients is real and long lasting and will be lost.

Evaluation of contralateral kidney, liver and lung after extracorporeal shock wave lithotripsy in rabbits.

PubMed

Senyucel, M F; Boybeyi, O; Ayva, S; Aslan, M K; Soyer, T; Demet, A I; Kısa, U; Basar, M; Cakmak, M A

2013-10-01

An experimental study was carried out to evaluate the effects of extracorporeal shock wave lithotripsy (ESWL) on contralateral kidney, liver and lung by histopathological and biochemical methods. Twelve New Zealand rabbits were allocated to two groups (n = 6). Tissues of control group (CG, n = 6) were harvested without any intervention. In ESWL group (EG), right kidneys were exposed to 3,000 shock waves at 14 kV energy using electro-hydraulic type ESWL device three times every other day. Both kidneys, liver, and right lobe of lung tissues in EG were harvested on seventh day. Kidneys were examined histopathologically for presence of glomerular and tubular injury, interstitial edema, congestion, inflammation and fibrosis. Livers were examined for hepatocyte vacuolization, congestion, portal inflammation and fibrosis. Lung tissues were examined for loss of normal structure, emphysema, interstitial congestion-edema, prominent alveolar septal vessels, interstitial inflammation, intra-alveolar hemorrhage, intraluminal hemorrhage, peribronchial edema, congestion, inflammation in bronchial wall and epithelial desquamation. Biochemical analysis of tissue samples was performed for oxidative injury markers. Histopathological evaluations revealed that tubular injury was found in both shocked and contralateral kidneys (p < 0.05). EG showed higher grades of portal fibrosis in liver and higher grades of peribronchial congestion in lung when compared to CG (p < 0.05). Biochemical evaluations of both kidneys showed that malondialdehyde levels were higher in EG than in CG (p < 0.05). ESWL causes histopathologic alterations both in shocked and contralateral kidneys. Extrarenal tissues such as liver and lung can be affected by shock waves histopathologically and oxidative injury of contralateral kidney may occur acutely after ESWL.

Legal briefing: organ donation and allocation.

PubMed

Pope, Thaddeus Mason

2010-01-01

This issue's "Legal Briefing" column covers legal developments pertaining to organ donation and allocation. This topic has been the subject of recent articles in JCE. Organ donation and allocation have also recently been the subjects of significant public policy attention. In the past several months, legislatures and regulatory agencies across the United States and across the world have changed, or considered changing, the methods for procuring and distributing human organs for transplantation. Currently, in the U.S., more than 100,000 persons are waiting for organ transplantation. In China, more than 1.5 million people are waiting. Given the chronic shortage of available organs (especially kidneys and livers) relative to demand, the primary focus of most legal developments has been on increasing the rate of donation. These and related developments are usefully divided into the following 12 topical categories: 1. Revised Uniform Anatomical Gift Act. 2. Presumed Consent and Opt-Out. 3. Mandated Choice. 4. Donation after Cardiac Death. 5. Payment and Compensation. 6. Donation by Prisoners. 7. Donor Registries. 8. Public Education. 9. Other Procurement Initiatives. 10. Lawsuits and Liability. 11. Trafficking and Tourism. 12. Allocation and Distribution.

Islet transplantation versus insulin therapy in patients with type 1 diabetes with severe hypoglycaemia or poorly controlled glycaemia after kidney transplantation (TRIMECO): a multicentre, randomised controlled trial.

PubMed

Lablanche, Sandrine; Vantyghem, Marie-Christine; Kessler, Laurence; Wojtusciszyn, Anne; Borot, Sophie; Thivolet, Charles; Girerd, Sophie; Bosco, Domenico; Bosson, Jean-Luc; Colin, Cyrille; Tetaz, Rachel; Logerot, Sophie; Kerr-Conte, Julie; Renard, Eric; Penfornis, Alfred; Morelon, Emmanuel; Buron, Fanny; Skaare, Kristina; Grguric, Gwen; Camillo-Brault, Coralie; Egelhofer, Harald; Benomar, Kanza; Badet, Lionel; Berney, Thierry; Pattou, François; Benhamou, Pierre-Yves

2018-05-15

Islet transplantation is indicated for patients with type 1 diabetes with severe hypoglycaemia or after kidney transplantation. We did a randomised trial to assess the efficacy and safety of islet transplantation compared with insulin therapy in these patients. In this multicentre, open-label, randomised controlled trial, we randomly assigned (1:1) patients with type 1 diabetes at 15 university hospitals to receive immediate islet transplantation or intensive insulin therapy (followed by delayed islet transplantation). Eligible patients were aged 18-65 years and had severe hypoglycaemia or hypoglycaemia unawareness, or kidney grafts with poor glycaemic control. We used computer-generated randomisation, stratified by centre and type of patient. Islet recipients were scheduled to receive 11 000 islet equivalents per kg bodyweight in one to three infusions. The primary outcome was proportion of patients with a modified β-score (in which an overall score of 0 was not allocated when stimulated C-peptide was negative) of 6 or higher at 6 months after first islet infusion in the immediate transplantation group or 6 months after randomisation in the insulin group. The primary analysis included all patients who received the allocated intervention; safety was assessed in all patients who received islet infusions. This trial is registered with ClinicalTrials.gov, number NCT01148680, and is completed. Between July 8, 2010, and July 29, 2013, 50 patients were randomly assigned to immediate islet transplantation (n=26) or insulin treatment (n=24), of whom three (one in the immediate islet transplantation group and two in the insulin therapy group) did not receive the allocated intervention. Median follow-up was 184 days (IQR 181-186) in the immediate transplantation group and 185 days (172-201) in the insulin therapy group. At 6 months, 16 (64% [95% CI 43-82]) of 25 patients in the immediate islet transplantation group had a modified β-score of 6 or higher versus none (0% [0-15]) of the 22 patients in the insulin group (p<0·0001). At 12 months after first infusion, bleeding complications had occurred in four (7% [2-18]) of 55 infusions, and a decrease in median glomerular filtration rate from 90·5 mL/min (IQR 76·6-94·0) to 71·8 mL/min (59·0-89·0) was observed in islet recipients who had not previously received a kidney graft and from 63·0 mL/min (55·0-71·0) to 57·0 mL/min (45·5-65·1) in islet recipients who had previously received a kidney graft. For the indications assessed in this study, islet transplantation effectively improves metabolic outcomes. Although studies with longer-term follow-up are needed, islet transplantation seems to be a valid option for patients with severe, unstable type 1 diabetes who are not responding to intensive medical treatments. However, immunosuppression can affect kidney function, necessitating careful selection of patients. Programme Hospitalier de Recherche Clinique grant from the French Government. Copyright © 2018 Elsevier Ltd. All rights reserved.

Market competition influences renal transplantation risk and outcomes.

PubMed

Adler, Joel T; Sethi, Rosh K V; Yeh, Heidi; Markmann, James F; Nguyen, Louis L

2014-09-01

To evaluate the impact of market competition on patient mortality and graft failure after kidney transplantation. Kidneys are initially allocated within 58 donation service areas (DSAs), which have varying numbers of transplant centers. Market competition is generally considered beneficial. The Scientific Registry of Transplant Recipients database was queried and the Herfindahl-Hirschman index (HHI), a measure of market competition, was calculated for each DSA from 2003 to 2012. Receipt of low-quality kidneys (Kidney Donor Profile Index ≥ 85) was modeled with multivariable logistic regression, and Cox proportional hazards models were created for graft failure and patient mortality. A total of 127,355 adult renal transplants were performed. DSAs were categorized as 7 no (HHI = 1), 17 low (HHI = 0.52-0.97), 17 medium (HHI = 0.33-0.51), or 17 high (HHI = 0.09-0.32) competition. For deceased donor kidney transplantation, increasing market competition was significantly associated with mortality [hazard ratio (HR): 1.11, P = 0.01], graft failure (HR: 1.18, P = 0.0001), and greater use of low-quality kidneys (odds ratio = 1.39, P < 0.0001). This was not true for living donor kidney transplantation (mortality HR: 0.94, P = 0.48; graft failure HR: 0.99, P = 0.89). Competition was associated with longer waitlists (P = 0.04) but not with the number of transplants per capita in a DSA (P = 0.21). Increasing market competition is associated with increased patient mortality and graft failure and the use of riskier kidneys. These results may represent more aggressive transplantation and tolerance of greater risk for patients who otherwise have poor alternatives. Market competition should be better studied to ensure optimal outcomes.

History of deceased organ donation, transplantation, and organ procurement organizations.

PubMed

Howard, Richard J; Cornell, Danielle L; Cochran, Larry

2012-03-01

The historical development of deceased organ donation, transplantation, and organ procurement organizations is reviewed. The concept of transplantation, taking parts from one animal or person and putting them into another animal or person, is ancient. The development of organ transplantation brought on the need for a source of organs. Although many early kidney transplants used kidneys from living donors, these donors could not satisfy the ever-growing need for organs, and extrarenal organs were recovered only from deceased donors. This need for organs to satisfy the great demand led to specialized organizations to identify deceased donors, manage them until recovery occurred, and to notify transplant centers that organs were available for their patients. The functions of these organ procurement organizations expanded to include other required functions such as education, accounting, and compliance with state and federal requirements. Because of the shortage of organs relative to the demand, lack of a unified organ allocation system, the perception that organs are a national resource and should be governed by national regulations, and to improve results of organ procurement organizations and transplant centers, the federal government has regulated virtually all phases of organ procurement and transplantation.

Kidney transplantation in the context of renal replacement therapy.

PubMed

Pesavento, Todd E

2009-12-01

Kidney transplantation has dramatically evolved from a life-saving yet unproven therapy for patients with renal failure to a mature field that is the preferred treatment for those suffering from ESRD. Patients who receive a transplant experience a 68% lower risk of death compared with those waiting on dialysis for a transplant. This benefit is afforded to all patient subgroups including the elderly (> or =70 yr), and diabetics, who can gain 11 yr of extra life with transplantation. Prolonged transplant wait times result in a higher risk of death but this can be ameliorated with preemptive transplantation. Future challenges will focus on appropriate organ allocation and addressing long-term renal function and comorbid conditions so patients can enjoy the full benefits of transplantation.

Long-Term Outcomes and Discard Rate of Kidneys by Decade of Extended Criteria Donor Age

PubMed Central

Messina, Maria; Diena, Davide; Dellepiane, Sergio; Guzzo, Gabriella; Lo Sardo, Luca; Fop, Fabrizio; Segoloni, Giuseppe P.; Amoroso, Antonio; Magistroni, Paola

2017-01-01

Background and objectives Extended criteria donors represent nowadays a main resource for kidney transplantation, and recovery criteria are becoming increasingly inclusive. However, the limits of this approach are not clear as well as the effects of extreme donor ages on long-term kidney transplantation outcomes. To address these issues, we performed a retrospective study on extended criteria donor kidney transplantation. Design, setting, participants, & measurements In total, 647 consecutive extended criteria donor kidney transplantations performed over 11 years (2003–2013) were included. Donor, recipient, and procedural variables were classified according to donor age decades (group A, 50–59 years old [n=91]; group B, 60–69 years old [n=264]; group C, 70–79 years old [n=265]; and group D, ≥80 years old [n=27]). Organs were allocated in single- or dual-kidney transplantation after a multistep evaluation including clinical and histologic criteria. Long-term outcomes and main adverse events were analyzed among age groups and in either single- or dual-kidney transplantation. Kidney discard rate incidence and causes were evaluated. Results Median follow-up was 4.9 years (25th; 75th percentiles: 2.7; 7.6 years); patient and graft survival were comparable among age groups (5-year patient survival: group A, 87.8%; group B, 88.1%; group C, 88.0%; and group D, 90.1%; P=0.77; graft survival: group A, 74.0%; group B, 74.2%; group C, 75.2%; and group D, 65.9%; P=0.62) and between dual-kidney transplantation and single-kidney transplantation except for group D, with a better survival for dual-kidney transplantation (P=0.04). No difference was found analyzing complications incidence or graft function over time. Kidney discard rate was similar in groups A, B, and C (15.4%, 17.7%, and 20.1%, respectively) and increased in group D (48.2%; odds ratio, 5.1 with A as the reference group; 95% confidence interval, 2.96 to 8.79). Conclusions Discard rate and long-term outcomes are similar among extended criteria donor kidney transplantation from donors ages 50–79 years old. Conversely, discard rate was strikingly higher among kidneys from octogenarian donors, but appropriate selection provides comparable long-term outcomes, with better graft survival for dual-kidney transplantation. PMID:27979977

Long-Term Outcomes and Discard Rate of Kidneys by Decade of Extended Criteria Donor Age.

PubMed

Messina, Maria; Diena, Davide; Dellepiane, Sergio; Guzzo, Gabriella; Lo Sardo, Luca; Fop, Fabrizio; Segoloni, Giuseppe P; Amoroso, Antonio; Magistroni, Paola; Biancone, Luigi

2017-02-07

Extended criteria donors represent nowadays a main resource for kidney transplantation, and recovery criteria are becoming increasingly inclusive. However, the limits of this approach are not clear as well as the effects of extreme donor ages on long-term kidney transplantation outcomes. To address these issues, we performed a retrospective study on extended criteria donor kidney transplantation. In total, 647 consecutive extended criteria donor kidney transplantations performed over 11 years (2003-2013) were included. Donor, recipient, and procedural variables were classified according to donor age decades (group A, 50-59 years old [n=91]; group B, 60-69 years old [n=264]; group C, 70-79 years old [n=265]; and group D, ≥80 years old [n=27]). Organs were allocated in single- or dual-kidney transplantation after a multistep evaluation including clinical and histologic criteria. Long-term outcomes and main adverse events were analyzed among age groups and in either single- or dual-kidney transplantation. Kidney discard rate incidence and causes were evaluated. Median follow-up was 4.9 years (25th; 75th percentiles: 2.7; 7.6 years); patient and graft survival were comparable among age groups (5-year patient survival: group A, 87.8%; group B, 88.1%; group C, 88.0%; and group D, 90.1%; P=0.77; graft survival: group A, 74.0%; group B, 74.2%; group C, 75.2%; and group D, 65.9%; P=0.62) and between dual-kidney transplantation and single-kidney transplantation except for group D, with a better survival for dual-kidney transplantation (P=0.04). No difference was found analyzing complications incidence or graft function over time. Kidney discard rate was similar in groups A, B, and C (15.4%, 17.7%, and 20.1%, respectively) and increased in group D (48.2%; odds ratio, 5.1 with A as the reference group; 95% confidence interval, 2.96 to 8.79). Discard rate and long-term outcomes are similar among extended criteria donor kidney transplantation from donors ages 50-79 years old. Conversely, discard rate was strikingly higher among kidneys from octogenarian donors, but appropriate selection provides comparable long-term outcomes, with better graft survival for dual-kidney transplantation. Copyright © 2017 by the American Society of Nephrology.

Haemodynamic-guided fluid administration for the prevention of contrast-induced acute kidney injury: the POSEIDON randomised controlled trial.

PubMed

Brar, Somjot S; Aharonian, Vicken; Mansukhani, Prakash; Moore, Naing; Shen, Albert Y-J; Jorgensen, Michael; Dua, Aman; Short, Lindsay; Kane, Kevin

2014-05-24

The administration of intravenous fluid remains the cornerstone treatment for the prevention of contrast-induced acute kidney injury. However, no well-defined protocols exist to guide fluid administration in this treatment. We aimed to establish the efficacy of a new fluid protocol to prevent contrast-induced acute kidney injury. In this randomised, parallel-group, comparator-controlled, single-blind phase 3 trial, we assessed the efficacy of a new fluid protocol based on the left ventricular end-diastolic pressure for the prevention of contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. The primary outcome was the occurrence of contrast-induced acute kidney injury, which was defined as a greater than 25% or greater than 0·5 mg/dL increase in serum creatinine concentration. Between Oct 10, 2010, and July 17, 2012, 396 patients aged 18 years or older undergoing cardiac catheterisation with an estimated glomerular filtration rate of 60 mL/min per 1·73 m(2) or less and one or more of several risk factors (diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years) were randomly allocated in a 1:1 ratio to left ventricular end-diastolic pressure-guided volume expansion (n=196) or the control group (n=200) who received a standard fluid administration protocol. Four computer-generated concealed randomisation schedules, each with permuted block sizes of 4, were used for randomisation, and participants were allocated to the next sequential randomisation number by sealed opaque envelopes. Patients and laboratory personnel were masked to treatment assignment, but the physicians who did the procedures were not masked. Both groups received intravenous 0·9% sodium chloride at 3 mL/kg for 1 h before cardiac catheterisation. Analyses were by intention to treat. Adverse events were assessed at 30 days and 6 months and all such events were classified by staff who were masked to treatment assignment. This trial is registered with ClinicalTrials.gov, number NCT01218828. Contrast-induced acute kidney injury occurred less frequently in patients in the left ventricular end-diastolic pressure-guided group (6·7% [12/178]) than in the control group (16·3% [28/172]; relative risk 0·41, 95% CI 0·22-0·79; p=0·005). Hydration treatment was terminated prematurely because of shortness of breath in three patients in each group. Left ventricular end-diastolic pressure-guided fluid administration seems to be safe and effective in preventing contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. Kaiser Permanente Southern California regional research committee grant. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of transcutaneous electrical nerve stimulation on pain, walking function, respiratory muscle strength and vital capacity in kidney donors: a protocol of a randomized controlled trial

PubMed Central

2013-01-01

Background Pain is a negative factor in the recovery process of postoperative patients, causing pulmonary alterations and complications and affecting functional capacity. Thus, it is plausible to introduce transcutaneous electrical nerve stimulation (TENS) for pain relief to subsequently reduce complications caused by this pain in the postoperative period. The objective of this paper is to assess the effects of TENS on pain, walking function, respiratory muscle strength and vital capacity in kidney donors. Methods/design Seventy-four patients will be randomly allocated into 2 groups: active TENS or placebo TENS. All patients will be assessed for pain intensity, walk function (Iowa Gait Test), respiratory muscle strength (maximal inspiratory pressure and maximal expiratory pressure) and vital capacity before and after the TENS application. The data will be collected by an assessor who is blinded to the group allocation. Discussion This study is the first to examine the effects of TENS in this population. TENS during the postoperative period may result in pain relief and improvements in pulmonary tests and mobility, thus leading to an improved quality of life and further promoting organ donation. Trial registration Registro Brasileiro de Ensaios Clinicos (ReBEC), number RBR-8xtkjp. PMID:23311705

Applicability and Limitations of Reliability Allocation Methods

NASA Technical Reports Server (NTRS)

Cruz, Jose A.

2016-01-01

Reliability allocation process may be described as the process of assigning reliability requirements to individual components within a system to attain the specified system reliability. For large systems, the allocation process is often performed at different stages of system design. The allocation process often begins at the conceptual stage. As the system design develops, more information about components and the operating environment becomes available, different allocation methods can be considered. Reliability allocation methods are usually divided into two categories: weighting factors and optimal reliability allocation. When properly applied, these methods can produce reasonable approximations. Reliability allocation techniques have limitations and implied assumptions that need to be understood by system engineers. Applying reliability allocation techniques without understanding their limitations and assumptions can produce unrealistic results. This report addresses weighting factors, optimal reliability allocation techniques, and identifies the applicability and limitations of each reliability allocation technique.

Salix alba attenuated oxidative stress in the heart and kidney of hypercholesterolemic rabbits.

PubMed

Amel Zabihi, Narges; Mahmoudabady, Maryam; Soukhtanloo, Mohammad; Hayatdavoudi, Parichehr; Beheshti, Farimah; Niazmand, Saeed

2018-01-01

Oxidative stress plays a critical role in the development of hypercholesterolemia-induced complications. This study evaluated the effects of aspirin and Salix alba hydroethanolic extract on oxidative stress in the heart and kidney of hypercholesterolemic rabbits. The antioxidant activity, as well as total phenolic and salicin content of S. alba (Sa) extract were assessed by DPPH radical scavenging activity, Folin-Ciocalteu and HPLC methods, respectively. Animals were divided into two groups of control (fed with normal chow), and HD (fed with high cholesterol diet for 6 weeks). Then, hypercholesterolemic animals allocated to the following treatment groups: CHO (received HD), Sa extract (HD plus extract 60 and 120 mg/kg), and aspirin (HD plus aspirin 120 mg/kg) and received the treatments on a daily basis for 6 weeks. MDA, GSH, and nitrite concentrations as well as the activities of SOD and CAT were evaluated in cardiac and kidney tissues. The scavenging activity, total phenolic content and salicin were 19.1 µg/ml (IC50), 153.75 ± 3.6 mg of gallic acid/g, and 18.03 µg/mg, respectively. In comparison to CHO group, MDA levels were diminished in Sa and ASA groups but GSH levels were improved. NO metabolites increased in the heart of Sa 120 mg/kg group and in the kidney of all Sa and ASA treated groups. SOD activity increased only in the heart of Sa groups and in the kidney of Sa and ASA groups. CAT activity increased in the heart and kidney tissues of all Sa and ASA treated groups. The results showed S. alba extract improved redox homeostasis in heart and kidney tissues of hypercholesterolemic rabbits. The extract antioxidant property may be related to its phenolic content.

Salix alba attenuated oxidative stress in the heart and kidney of hypercholesterolemic rabbits

PubMed Central

Amel Zabihi, Narges; Mahmoudabady, Maryam; Soukhtanloo, Mohammad; Hayatdavoudi, Parichehr; Beheshti, Farimah; Niazmand, Saeed

2018-01-01

Objective: Oxidative stress plays a critical role in the development of hypercholesterolemia-induced complications. This study evaluated the effects of aspirin and Salix alba hydroethanolic extract on oxidative stress in the heart and kidney of hypercholesterolemic rabbits. Materials and Methods: The antioxidant activity, as well as total phenolic and salicin content of S. alba (Sa) extract were assessed by DPPH radical scavenging activity, Folin-Ciocalteu and HPLC methods, respectively. Animals were divided into two groups of control (fed with normal chow), and HD (fed with high cholesterol diet for 6 weeks). Then, hypercholesterolemic animals allocated to the following treatment groups: CHO (received HD), Sa extract (HD plus extract 60 and 120 mg/kg), and aspirin (HD plus aspirin 120 mg/kg) and received the treatments on a daily basis for 6 weeks. MDA, GSH, and nitrite concentrations as well as the activities of SOD and CAT were evaluated in cardiac and kidney tissues. Results: The scavenging activity, total phenolic content and salicin were 19.1 µg/ml (IC50), 153.75 ± 3.6 mg of gallic acid/g, and 18.03 µg/mg, respectively. In comparison to CHO group, MDA levels were diminished in Sa and ASA groups but GSH levels were improved. NO metabolites increased in the heart of Sa 120 mg/kg group and in the kidney of all Sa and ASA treated groups. SOD activity increased only in the heart of Sa groups and in the kidney of Sa and ASA groups. CAT activity increased in the heart and kidney tissues of all Sa and ASA treated groups. Conclusion: The results showed S. alba extract improved redox homeostasis in heart and kidney tissues of hypercholesterolemic rabbits. The extract antioxidant property may be related to its phenolic content. PMID:29379769

Outcomes of dual adult kidney transplants in the United States: an analysis of the OPTN/UNOS database.

PubMed

Gill, Jagbir; Cho, Yong W; Danovitch, Gabriel M; Wilkinson, Alan; Lipshutz, Gerald; Pham, Phuong-Thu; Gill, John S; Shah, Tariq; Bunnapradist, Suphamai

2008-01-15

The organ shortage has resulted in increased use of kidneys from expanded criteria donors (ECD). For ECD kidneys unsuitable for single use, dual kidney transplants (DKT) may be possible. There are limited data comparing outcomes of DKT to single kidney ECD transplants, making it unclear where DKT fits in the current allocation scheme. Our purpose was to compare outcomes of DKT and ECD transplants in the United States. From 2000 to 2005, a total of 625 DKT, 7686 single kidney ECD, and 6,044 SCD transplants from donors aged>or=50 years were identified from the Organ Procurement and Transplantation Network/United Network for Organ Sharing data. Allograft survival was the primary outcome. DKT comprised 4% of kidney transplants from donors aged>or=50 years. Compared to the ECD donor group, the DKT donor group was older (mean age 64.6+/-7.7 years vs. 59.9+/-6.2 years) and consisted of more African Americans (13.1% vs. 9.9%), and more diabetic donors (16.3% vs. 10.4%; P<0.001). Mean cold ischemic time was longer in DKT (22.2+/-9.7 hr), but rates of delayed graft function were lower (29.3%) compared to ECD transplants (33.6%, P=0.03). Three-year overall graft survival was 79.8% for DKT and 78.3% for ECD transplants. DKT were infrequent and had outcomes comparable to ECD transplants, despite the use of organs from higher risk donors. With a more upfront approach to DKT by offering this option to patients at the time of wait-listing as part of an ECD algorithm, we may be able to further optimize outcomes of DKT and minimize discard of potential organs.

Kidney Transplantation Results in Very Highly Sensitized Patients Included in a Virtual Crossmatch Program: Analysis of Kidney Pairs.

PubMed

Mazuecos, A; Alvarez, A; Nieto, A; Gentil, M A; Cabello, M; Rodriguez-Benot, A; Gracia, C; Gonzalez, F; Castro, P; Alonso, M

2016-11-01

Kidney transplantation in highly-sensitized (HS) patients can improve with organ-exchange strategies based on virtual crossmatch (V-XM). Experience in very-HS patients is limited. In June 2012, Andalusia started a V-XM protocol for very-HS patients (calculated panel reactive antibodies ≥95%). After organ allocation a cytotoxic-XM performed immediately before transplantation had to be negative for surgery to proceed. We analyzed results up until December 2015. Whenever possible we also compared the course of the recipient (non-HS) of the other kidney from the same donor. Of the 57 grafts, 52 kidney transplantations were performed (the pretransplantation cytotoxic-XM was positive in 5; predictive value 91.3%). Five patients (9.6%) experienced acute rejection (4 antibody-mediated rejections [AMRs]; 7.6%). Donor-specific antibodies developed in 10 patients. No patient died. One-year graft survival was 98%. We compared the course of the non-HS recipient of the other kidney, excluding cases with no pair (n = 5), pairs who were children recipients (n = 3), pancreas-kidney recipients (n = 5), or pairs already included in the V-XM protocol (n = 4). Finally, 35 pairs were studied. More HS-patients developed donor-specific antibodies (P = .016). No significant differences were seen in acute rejection, but AMR was more common (P = .057). No deaths occurred in either group, and there were no differences in graft survival or renal function. Although a few patients still developed AMR, our V-XM based protocol with a final pretransplantation cytotoxic-XM achieved very satisfactory results. Although the number of patients was limited, the initial survival of these high-risk recipients was comparable to the controls. Copyright © 2016 Elsevier Inc. All rights reserved.

Apelin/APJ system: A novel potential therapy target for kidney disease.

PubMed

Huang, Zhen; Wu, Lele; Chen, Linxi

2018-05-01

Apelin is an endogenous ligand of seven-transmembrane G protein-coupled receptor APJ. Apelin and APJ are distributed in various tissues, including the heart, lung, kidney, and even in tumor tissues. Studies show that apelin mRNA is highly expressed in the inner stripe of kidney outer medulla, which plays an important role in process of water and sodium balance. Additionally, more studies also indicate that apelin/APJ system exerts a broad range of activities in kidney. Therefore, we review the role of apelin/APJ system in kidney diseases such as renal fibrosis, renal ischemia/reperfusion injury, diabetic nephropathy, polycystic kidney disease, and hemodialysis (HD). Apelin/APJ system can improve renal interstitial fibrosis by reducing the deposition of extracellular matrix. Apelin/APJ system significantly reduces renal ischemia/reperfusion injury by inhibiting renal cell death. Apelin/APJ system involves the progression of diabetic nephropathy (DN). Apelin/APJ system also predicts the process of polycystic kidney disease. Besides, apelin/APJ system prevents some dialysis complications in HD patients. And apelin/APJ system alleviates chronic kidney disease (CKD) by inhibiting vascular calcification (VC). Overall, apelin/APJ system plays diversified roles in kidney disease and may be a potential target for the treatment of kidney disease. © 2017 Wiley Periodicals, Inc.

The effects of saline water consumption on the ultrasonographic and histopathological appearance of the kidney and liver in Barki sheep.

PubMed

Ghanem, Mohamed; Zeineldin, Mohamed; Eissa, Attia; El Ebissy, Eman; Mohammed, Rasha; Abdelraof, Yassein

2018-05-18

The objective of this study was to evaluate the impact of varying degrees of water salinity on the ultrasonographical and histopathological appearance of the liver and kidneys in Barki sheep. Thirty Barki sheep (initial weight, 29.48 ± 0.81 kg) were allocated into three groups (n=10 per group) based on the type of drinking water for 9 months: the tap water (TW) group (350 ppm total dissolved solids [TDS]); the moderate saline water (MSW) group (4,557 ppm TDS); and the high saline water (HSW) group (8,934 ppm TDS). After 9 months, the body weight was significantly decreased in sheep subjected to MSW (P=0.0347) and HSW (P=0.0424). Alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, urea, and creatinine were significantly increased (P<0.05) in sheep subjected to MSW and HSW. Ultrasonographic examination of the right and left kidneys revealed an increased length of both kidneys with crystal formation, particularly in male sheep. Ultrasonographic examination of the liver showed hyperechogenic dots varying in size and number between males and females. Histopathological examination of kidney revealed significant changes in both MSW and HSW groups such as hyaline matrix formation, atrophied glomerular tufts, and intramedullary congestion. Histopathological examination of the liver revealed slight fatty liver changes, slight fibrosis around the bile duct, massive inflammatory cell infiltration and vacuolar changes of hepatocytes in both MSW and HSW groups. In conclusion, water salinity negatively affects the body weight, liver and kidney appearance of Barki sheep and thus sheep production.

Task allocation in a distributed computing system

NASA Technical Reports Server (NTRS)

Seward, Walter D.

1987-01-01

A conceptual framework is examined for task allocation in distributed systems. Application and computing system parameters critical to task allocation decision processes are discussed. Task allocation techniques are addressed which focus on achieving a balance in the load distribution among the system's processors. Equalization of computing load among the processing elements is the goal. Examples of system performance are presented for specific applications. Both static and dynamic allocation of tasks are considered and system performance is evaluated using different task allocation methodologies.

X-ray diffraction and SEM study of kidney stones in Israel: quantitative analysis, crystallite size determination, and statistical characterization.

PubMed

Uvarov, Vladimir; Popov, Inna; Shapur, Nandakishore; Abdin, Tamer; Gofrit, Ofer N; Pode, Dov; Duvdevani, Mordechai

2011-12-01

Urinary calculi have been recognized as one of the most painful medical disorders. Tenable knowledge of the phase composition of the stones is very important to elucidate an underlying etiology of the stone disease. We report here the results of quantitative X-ray diffraction phase analysis performed on 278 kidney stones from the 275 patients treated at the Department of Urology of Hadassah Hebrew University Hospital (Jerusalem, Israel). Quantification of biominerals in multicomponent samples was performed using the normalized reference intensity ratio method. According to the observed phase compositions, all the tested stones were classified into five chemical groups: oxalates (43.2%), phosphates (7.7%), urates (10.3%), cystines (2.9%), and stones composed of a mixture of different minerals (35.9%). A detailed analysis of each allocated chemical group is presented along with the crystallite size calculations for all the observed crystalline phases. The obtained results have been compared with the published data originated from different geographical regions. Morphology and spatial distribution of the phases identified in the kidney stones were studied with scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). This type of detailed study of phase composition and structural characteristics of the kidney stones was performed in Israel for the first time.

Dynamic resource allocation in a hierarchical multiprocessor system: A preliminary study

NASA Technical Reports Server (NTRS)

Ngai, Tin-Fook

1986-01-01

An integrated system approach to dynamic resource allocation is proposed. Some of the problems in dynamic resource allocation and the relationship of these problems to system structures are examined. A general dynamic resource allocation scheme is presented. A hierarchial system architecture which dynamically maps between processor structure and programs at multiple levels of instantiations is described. Simulation experiments were conducted to study dynamic resource allocation on the proposed system. Preliminary evaluation based on simple dynamic resource allocation algorithms indicates that with the proposed system approach, the complexity of dynamic resource management could be significantly reduced while achieving reasonable effective dynamic resource allocation.

An analysis of discrepancies between United Kingdom cancer research funding and societal burden and a comparison to previous and United States values.

PubMed

Carter, Ashley J R; Delarosa, Beverly; Hur, Hannah

2015-11-02

Ideally, the allocation of research funding for each specific type of cancer should be proportional to its societal burden. This burden can be estimated with the metric 'years of life lost' (YLL), which combines overall mortality and age at death. Using United Kingdom data from 2010, we compared research funding from the National Cancer Research Institute to this YLL burden metric for 26 types of cancers in order to identify the discrepancies between cancer research funding allocation and societal burden. We also compared these values to United States data from 2010 and United Kingdom data published in 2005. Our study revealed a number of discrepancies between cancer research funding and burden. Some cancers are funded at levels far higher than their relative burden suggests (testicular, leukaemia, Hodgkin's lymphoma, breast, cervical, ovarian, prostate) while other cancers appear under-funded (gallbladder, lung, nasopharyngeal, intestine, stomach, pancreatic, thyroid, oesophageal, liver, kidney, bladder, and brain/central nervous system). United Kingdom funding patterns over the past decade have generally moved to increase funding to previously under-funded cancers with one notable exception showing a converse trend (breast cancer). The broad relationship between United Kingdom and United States funding patterns is similar with a few exceptions (e.g. leukaemia, Hodgkin's lymphoma, prostate, testicular cancer). There are discrepancies between cancer research funding allocation and societal burden in the United Kingdom. These discrepancies are broadly similar in both the United Kingdom and the United States and, while they appear to be improving, this is not consistent across all types of cancer.

Comparison of HLA-A, -B and -DRB1 Loci Polymorphism between Kidney Transplants of Uremia Patients and Healthy Individuals in Central China

PubMed Central

Gao, Shilin; Feng, Guiwen; Feng, Yonghua; Wang, Zhigang; Zhang, Xiaobai

2016-01-01

Chronic kidney disease is becoming a global public health problem, which will usually cause uremia at the end stage of chronic kidney failure. So far, kidney transplant is the most effective and proper therapy for uremia, however, the short supply of matched donor kidney has been a persistent bottleneck for transplantation. HLA matching of HLA-A, -B and -DRB1 loci is very important for the allocation of kidney transplants. In this study, we investigated genotypes of HLA-A, -B and -DRB1 loci based on 1,464 uremia patients and 10,000 unrelated healthy individuals in Henan province of China, and compared the frequency distribution of these HLA alleles and corresponding haplotypes between patient and healthy groups. We detected 23 HLA-A, 49 HLA-B and 17 HLA-DRB1 alleles in total. The predominant alleles of HLA-A, -B and -DRB1 loci in patients are the same as those in healthy group. The seven most frequent alleles account for about 87%, 50%, and 77% at HLA-A, -B and -DRB1 loci, respectively. The haplotypes (combinations of HLA-A, -B, and -DRB1) with significantly different frequency between patients and controls mostly account for less than 1%. Overall, this suggests that HLA matching is not a potential difficulty for kidney transplant of uremia patients. However, three of the top seven frequent HLA-DRB1 alleles have a significantly different distribution in patients and controls, while only one alleles for HLA-B and zero for HLA-A loci. These HLA-DRB1 alleles may be closely associated with uremia. This study sheds new lights on the composition and difference of HLA genotypes in uremia patients and healthy populations in Central China that can serve as a guide to HLA matching for kidney transplants and a resource for HLA typing-related studies. PMID:27780235

Omega-3 Long-Chain Fatty Acids in the Heart, Kidney, Liver and Plasma Metabolite Profiles of Australian Prime Lambs Supplemented with Pelleted Canola and Flaxseed Oils.

PubMed

Nguyen, Don V; Le, Van H; Nguyen, Quang V; Malau-Aduli, Bunmi S; Nichols, Peter D; Malau-Aduli, Aduli E O

2017-08-17

The objective of the study was to ascertain whether human health beneficial omega-3 long-chain (≥C 20 ) polyunsaturated fatty acid ( n -3 LC-PUFA) content in heart, kidney and liver can be enhanced by supplementing prime lambs with graded levels of canola and flaxseed oil. Health status of the lambs, as a consequence of the supplementation, was also investigated by examining their plasma metabolites. Sixty purebred and first-cross lambs were allocated to one of five treatments of lucerne hay basal diet supplemented with isocaloric and isonitrogenous wheat-based pellets without oil inclusion (Control) or graded levels of canola oil at 2.5% (2.5C), 5% (5C), flaxseed oil at 2.5% (2.5F) and 5% (5F) in a completely randomised design. Pre-slaughter blood, post-slaughter kidney, liver and heart samples were analysed for plasma metabolite and fatty acid profiles. Summations of docosapentaenoic acid and docosahexaenoic acid, and total n -3 LC-PUFA were enhanced in the liver and kidney of 5F supplemented lambs with a marked decrease in n -6/ n -3 ratio and significant breed differences detected. There were generally no deleterious impacts on animal health status. A combination of 5% oil supplementation and lamb genetics is an effective and strategic management tool for enhancing n -3 LC-PUFA contents of heart, kidney and liver without compromising lamb health.

Omega–3 Long-Chain Fatty Acids in the Heart, Kidney, Liver and Plasma Metabolite Profiles of Australian Prime Lambs Supplemented with Pelleted Canola and Flaxseed Oils

PubMed Central

Nguyen, Don V.; Le, Van H.; Nguyen, Quang V.; Malau-Aduli, Bunmi S.; Nichols, Peter D.

2017-01-01

The objective of the study was to ascertain whether human health beneficial omega–3 long-chain (≥C20) polyunsaturated fatty acid (n-3 LC-PUFA) content in heart, kidney and liver can be enhanced by supplementing prime lambs with graded levels of canola and flaxseed oil. Health status of the lambs, as a consequence of the supplementation, was also investigated by examining their plasma metabolites. Sixty purebred and first-cross lambs were allocated to one of five treatments of lucerne hay basal diet supplemented with isocaloric and isonitrogenous wheat-based pellets without oil inclusion (Control) or graded levels of canola oil at 2.5% (2.5C), 5% (5C), flaxseed oil at 2.5% (2.5F) and 5% (5F) in a completely randomised design. Pre-slaughter blood, post-slaughter kidney, liver and heart samples were analysed for plasma metabolite and fatty acid profiles. Summations of docosapentaenoic acid and docosahexaenoic acid, and total n-3 LC-PUFA were enhanced in the liver and kidney of 5F supplemented lambs with a marked decrease in n-6/n-3 ratio and significant breed differences detected. There were generally no deleterious impacts on animal health status. A combination of 5% oil supplementation and lamb genetics is an effective and strategic management tool for enhancing n-3 LC-PUFA contents of heart, kidney and liver without compromising lamb health. PMID:28817082

21 CFR 876.5880 - Isolated kidney perfusion and transport system and accessories.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Isolated kidney perfusion and transport system and....5880 Isolated kidney perfusion and transport system and accessories. (a) Identification. An isolated kidney perfusion and transport system and accesssories is a device that is used to support a donated or a...

21 CFR 876.5880 - Isolated kidney perfusion and transport system and accessories.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Isolated kidney perfusion and transport system and....5880 Isolated kidney perfusion and transport system and accessories. (a) Identification. An isolated kidney perfusion and transport system and accesssories is a device that is used to support a donated or a...

System Resource Allocations | High-Performance Computing | NREL

Science.gov Websites

Allocations System Resource Allocations To use NREL's high-performance computing (HPC) resources : Compute hours on NREL HPC Systems including Peregrine and Eagle Storage space (in Terabytes) on Peregrine , Eagle and Gyrfalcon. Allocations are principally done in response to an annual call for allocation

Histopathological and biochemical investigations of protective role of honey in rats with experimental aflatoxicosis.

PubMed

Yaman, Turan; Yener, Zabit; Celik, Ismail

2016-07-21

Natural honey (honey) is considered as a part of traditional medicine all over the world. It has both antimicrobial and antioxidant properties, useful in stimulation of wounds and burns healing and gastric ulcers treatment. The aim of this study, for the first time, was to investigate the antioxidant properties and protective role of honey against carcinogen chemical aflatoxin (AF) exposure in rats, which were evaluated by histopathological changes in liver and kidney, measuring level of serum marker enzymes [aspartate aminotransferase (AST), alanin aminotransferase (ALT), gamma glutamil transpeptidase (GGT)], antioxidant defense systems [Reduced glutathione (GSH), glutathione reductase (GR), superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase (CAT)], and lipid peroxidation content in liver, erythrocyte, brain, kidney, heart and lungs. Eighteen healthy Sprague-Dawley rats were randomly allocated into three experimental groups: A (Control), B (AF-treated) and C (AF + honey-treated). While rats in group A were fed with a diet without AF, B, and C groups received 25 μg of AF/rat/day, where C group additionally received 1 mL/kg of honey by gavage for 90 days. At the end of the 90-day experimental period, we found that the honey supplementation decreased the lipid peroxidation and the levels of enzyme associated with liver damage, increased enzymatic and non-enzymatic antioxidants in the AF + honey-treated rats. Hepatoprotective and nephroprotective effects of honey is further substantiated by showing almost normal histological architecture in AF + honey-treated group, compared to degenerative changes in the liver and kidney of AF-treated rats. Additionally, honey supplementation ameliorated antioxidant defens systems and lipid peroxidation in content in other tissues of AF + honey treated rats. The present study indicates that honey has a hepatoprotective and nephroprotective effect in rats with experimental aflatoxicosis due to its antioxidant activity.

A simplified donor risk index for predicting outcome after deceased donor kidney transplantation.

PubMed

Watson, Christopher J E; Johnson, Rachel J; Birch, Rhiannon; Collett, Dave; Bradley, J Andrew

2012-02-15

We sought to determine the deceased donor factors associated with outcome after kidney transplantation and to develop a clinically applicable Kidney Donor Risk Index. Data from the UK Transplant Registry on 7620 adult recipients of adult deceased donor kidney transplants between 2000 and 2007 inclusive were analyzed. Donor factors potentially influencing transplant outcome were investigated using Cox regression, adjusting for significant recipient and transplant factors. A United Kingdom Kidney Donor Risk Index was derived from the model and validated. Donor age was the most significant factor predicting poor transplant outcome (hazard ratio for 18-39 and 60+ years relative to 40-59 years was 0.78 and 1.49, respectively, P<0.001). A history of donor hypertension was also associated with increased risk (hazard ratio 1.30, P=0.001), and increased donor body weight, longer hospital stay before death, and use of adrenaline were also significantly associated with poorer outcomes up to 3 years posttransplant. Other donor factors including donation after circulatory death, history of cardiothoracic disease, diabetes history, and terminal creatinine were not significant. A donor risk index based on the five significant donor factors was derived and confirmed to be prognostic of outcome in a validation cohort (concordance statistic 0.62). An index developed in the United States by Rao et al., Transplantation 2009; 88: 231-236, included 15 factors and gave a concordance statistic of 0.63 in the UK context, suggesting that our much simpler model has equivalent predictive ability. A Kidney Donor Risk Index based on five donor variables provides a clinically useful tool that may help with organ allocation and informed consent.

Reversal of anemia with allogenic RBC transfusion prevents post-cardiopulmonary bypass acute kidney injury in swine

PubMed Central

Patel, Nishith N.; Lin, Hua; Toth, Tibor; Welsh, Gavin I.; Jones, Ceri; Ray, Paramita; Satchell, Simon C.; Sleeman, Philippa; Angelini, Gianni D.

2011-01-01

Anemia during cardiopulmonary bypass (CPB) is strongly associated with acute kidney injury in clinical studies; however, reversal of anemia with red blood cell (RBC) transfusions is associated with further renal injury. To understand this paradox, we evaluated the effects of reversal of anemia during CPB with allogenic RBC transfusion in a novel large-animal model of post-cardiac surgery acute kidney injury with significant homology to that observed in cardiac surgery patients. Adult pigs undergoing general anesthesia were allocated to a Sham procedure, CPB alone, Sham+RBC transfusion, or CPB+RBC transfusion, with recovery and reassessment at 24 h. CPB was associated with dilutional anemia and caused acute kidney injury in swine characterized by renal endothelial dysfunction, loss of nitric oxide (NO) bioavailability, vasoconstriction, medullary hypoxia, cortical ATP depletion, glomerular sequestration of activated platelets and inflammatory cells, and proximal tubule epithelial cell stress. RBC transfusion in the absence of CPB also resulted in renal injury. This was characterized by endothelial injury, microvascular endothelial dysfunction, platelet activation, and equivalent cortical tubular epithelial phenotypic changes to those observed in CPB pigs, but occurred in the absence of severe intrarenal vasoconstriction, ATP depletion, or reductions in creatinine clearance. In contrast, reversal of anemia during CPB with RBC transfusion prevented the reductions in creatinine clearance, loss of NO bioavailability, platelet activation, inflammation, and epithelial cell injury attributable to CPB although it did not prevent the development of significant intrarenal vasoconstriction and endothelial dysfunction. In conclusion, contrary to the findings of observational studies in cardiac surgery, RBC transfusion during CPB protects pigs against acute kidney injury. Our study underlines the need for translational research into indications for transfusion and prevention strategies for acute kidney injury. PMID:21653630

Effects of exercise on kidney function among non-diabetic patients with hypertension and renal disease: randomized controlled trial.

PubMed

Barcellos, Franklin C; Santos, Iná S; Mielke, Grégore Iven; del Vecchio, Fabrício B; Hallal, Pedro C

2012-08-28

Chronic kidney disease is an important public health threat. Such patients present high morbidity and mortality due to cardiovascular disease, with low quality of life and survival, and also high expenditure resulting from the treatment. Arterial hypertension is both a cause and a complication of kidney disease; also, arterial hypertension is a risk factor for cardiovascular disease among patients with kidney diseases. There is some evidence that exercise interventions may be beneficial to chronic kidney disease patients, but previous studies included only end-stage patients, i.e. those undergoing dialysis. This study aims to evaluate the effect of exercise on kidney function, quality of life and other risk factors for cardiovascular disease among non-diabetic chronic hypertensive kidney disease patients who are not undergoing dialysis. The participants will be located through screening hypertensive patients attended within the public healthcare network in Pelotas, a city in south of Brazil. Eligible individuals will be those with glomerular filtration rate between 15 and 59 ml/min x 1.73 m(2). The randomization will be done in fixed-size blocks of six individuals such that 75 participants will be allocated to each group. At baseline, information on demographic, socioeconomic, behavioral, anthropometric, blood pressure and quality-of-life variables will be collected, and laboratory tests will be performed. The intervention will consist of three weekly physical exercise sessions lasting 60-75 minutes each, with a total duration of 16 weeks. The outcomes will be the kidney function progression rate, quality of life, blood pressure, lipid profile, hemoglobin level, ultrasensitive C-reactive protein level, and ankle-arm index. The patients in both groups (intervention and control) will be reassessed and compared partway through the study (8th week), at the end of the intervention (16th week) and in the 8th week after the end of the intervention. There is still a scarcity of data relating to the effect of physical exercise among the most numerous group of individuals with kidney disease, i.e. patients undergoing conservative treatment. In particular, there is a lack of randomized controlled studies. This study will help fill this gap.

Dynamic MRI-based computer aided diagnostic systems for early detection of kidney transplant rejection: A survey

NASA Astrophysics Data System (ADS)

Mostapha, Mahmoud; Khalifa, Fahmi; Alansary, Amir; Soliman, Ahmed; Gimel'farb, Georgy; El-Baz, Ayman

2013-10-01

Early detection of renal transplant rejection is important to implement appropriate medical and immune therapy in patients with transplanted kidneys. In literature, a large number of computer-aided diagnostic (CAD) systems using different image modalities, such as ultrasound (US), magnetic resonance imaging (MRI), computed tomography (CT), and radionuclide imaging, have been proposed for early detection of kidney diseases. A typical CAD system for kidney diagnosis consists of a set of processing steps including: motion correction, segmentation of the kidney and/or its internal structures (e.g., cortex, medulla), construction of agent kinetic curves, functional parameter estimation, diagnosis, and assessment of the kidney status. In this paper, we survey the current state-of-the-art CAD systems that have been developed for kidney disease diagnosis using dynamic MRI. In addition, the paper addresses several challenges that researchers face in developing efficient, fast and reliable CAD systems for the early detection of kidney diseases.

A Comparison of Red Cell Rejuvenation versus Mechanical Washing for the Prevention of Transfusion-associated Organ Injury in Swine.

PubMed

Woźniak, Marcin J; Qureshi, Saqib; Sullo, Nikol; Dott, William; Cardigan, Rebecca; Wiltshire, Michael; Nath, Mintu; Patel, Nishith N; Kumar, Tracy; Goodall, Alison H; Murphy, Gavin J

2018-02-01

We evaluated the effects of two interventions that modify the red cell storage lesion on kidney and lung injury in experimental models of transfusion. White-landrace pigs (n = 32) were allocated to receive sham transfusion (crystalloid), 14-day stored allogeneic red cells, 14-day red cells washed using the red cells washing/salvage system (CATS; Fresenius, Germany), or 14-day red cells rejuvenated using the inosine solution (Rejuvesol solution; Zimmer Biomet, USA) and washed using the CATS device. Functional, biochemical, and histologic markers of organ injury were assessed for up to 24 h posttransfusion. Transfusion of 14 day red cells resulted in lung injury (lung injury score vs. sham, mean difference -0.3 (95% CI, -0.6 to -0.1; P = 0.02), pulmonary endothelial dysfunction, and tissue leukocyte sequestration. Mechanical washing reduced red cell-derived microvesicles but increased cell-free hemoglobin in 14-day red cell units. Transfusion of washed red cells reduced leukocyte sequestration but did not reduce the lung injury score (mean difference -0.2; 95% CI, -0.5 to 0.1; P = 0.19) relative to 14-day cells. Transfusion of washed red cells also increased endothelial activation and kidney injury. Rejuvenation restored adenosine triphosphate to that of fresh red cells and reduced microvesicle concentrations without increasing cell-free hemoglobin release. Transfusion of rejuvenated red cells reduced plasma cell-free hemoglobin, leukocyte sequestration, and endothelial dysfunction in recipients and reduced lung and kidney injury relative to 14-day or washed 14-day cells. Reversal of the red cell storage lesion by rejuvenation reduces transfusion-associated organ injury in swine.

OPTN/SRTR 2016 Annual Data Report: Pancreas.

PubMed

Kandaswamy, R; Stock, P G; Gustafson, S K; Skeans, M A; Curry, M A; Prentice, M A; Fox, A; Israni, A K; Snyder, J J; Kasiske, B L

2018-01-01

The number of pancreas transplants performed in the United States increased by 7.0% in 2016 over the previous year, the first such increase in more than a decade, largely attributable to an increase in simultaneous kidney pancreas transplants. Transplant rates increased in 2016, and mortality on the waiting list decreased. The declining enthusiasm for pancreas after kidney (PAK) transplants persisted. The uniform definition of graft failure was approved by the OPTN Board of Directors in 2015 and will be implemented in early 2018. Meanwhile, SRTR continues to refrain from reporting pancreas graft failure data. The OPTN/UNOS Pancreas Transplantation Committee is seeking to broaden allocation of pancreata across compatible ABO blood types in a proposal out for public comment July 31 to October 2, 2017. A new initiative to provide guidance on the benefits of PAK transplants is also out for public comment.  .

The UNOS Renal Transplant Registry: Review of the Last Decade.

PubMed

Andre, Mark; Huang, Edmund; Everly, Matthew; Bunnapradist, Suphamai

2014-01-01

Kidney transplantation has become a preferred treatment for end-stage renal disease (ESRD) as transplant recipients enjoy freedom from dialysis and improvement in both quality and quantity of life. More patients are being placed on the transplant waiting list, although the waiting list patients still only represent a very small fraction of ESRD patients. The characteristics of both waitlisted and transplanted patients have changed considerably in the last decade, as the ESRD population has aged and waiting list times have increased. Over the last 10 years, we have witnessed an increasingly severe shortage of kidney donors. Even with increasing efforts of the transplant community to expand the donor pool by including larger numbers of high risk deceased donor transplants, the overall number of kidney transplants has remained relatively stable. Those who do receive transplants, however, benefit from excellent transplant outcomes. The use of paired exchange/chain transplant donors has increased the living donor pool significantly and with outstanding results. Belatacept, a costimulation blockage drug, represents a new class of transplant immunosuppression. It has been used sparingly in the first few years of its approval. Most kidney transplant patients are still maintained on immunosuppressive agents that were approved almost two decades ago. In the next decade, we will certainly continue to deal with an organ shortage as the number of eligible and waitlisted patients is likely to increase. Effective and efficient organ allocation policies will be increasingly necessary to address this scarcity. Optimizing the transplant candidate work-up, improving maintenance of waitlisted patients, and providing optimal post-transplant medical care will be vital to the continued success of kidney transplantation.

Mechanisms of "kidney governing bones" theory in traditional Chinese medicine.

PubMed

Ju, Dahong; Liu, Meijie; Zhao, Hongyan; Wang, Jun

2014-09-01

Studies conducted by our group on the mechanism of "kidney governing bones" theory in traditional Chinese medicine (TCM) are reviewed in this paper. Conclusions can be summarized as follows. (1) Neuroendocrine-immune network (NIN)-osteoclast regulatory pathway OPG-RANKL-RANK is one of the mechanisms of "kidney governing bones." Although kidney-reinforcing therapy is regarded as one of the holistic regulatory mechanisms of the body, characteristic holistic regulation in TCM can be reflected through nonselective regulation of the NIN during kidney reinforcement therapy, which can be used to treat osteoporosis through microadjustments in the microenvironment of the bone marrow. (2) Marrow exhaustion in TCM, which is the state wherein lipocytes in the bone marrow increase whereas other cells decrease, serves as the pathogenesis of osteoporosis brought about by failure of the "kidney governing bones." (3) The kidney in TCM can be regarded as a complex system comprising multiple functional units in the body, including the unit "governing bones." Kidney deficiency refers to a deficiency in only one or more units of the kidney system and not the whole system itself, which explains the kidney-reinforcing effect of many herbs; some herbs can treat osteoporosis, but some cannot. Although both classified as kidney-reinforcing agents, the former can resolve failure of the "kidney governing bones" unit while the latter regulates the failure of other units in the kidney system. Despite the current understanding on "kidney governing bones" theory, the mechanism of "kidney governing bones" remains complicated and unresolved. Thus, further studies in this area are warranted.

HLA-DQ Mismatches and Rejection in Kidney Transplant Recipients

PubMed Central

Chapman, Jeremy R.; Coates, Patrick T.; Lewis, Joshua R.; Russ, Graeme R.; Watson, Narelle; Holdsworth, Rhonda; Wong, Germaine

2016-01-01

Background and objectives The current allocation algorithm for deceased donor kidney transplantation takes into consideration HLA mismatches at the ABDR loci but not HLA mismatches at other loci, including HLA-DQ. However, the independent effects of incompatibilities for the closely linked HLA-DQ antigens in the context of HLA-DR antigen matched and mismatched allografts are uncertain. We aimed to determine the effect of HLA-DQ mismatches on renal allograft outcomes. Design, setting, participants, & measurements Using data from the Australia and New Zealand Dialysis and Transplant Registry, we examined the association between HLA-DQ mismatches and acute rejections in primary live and deceased donor kidney transplant recipients between 2004 and 2012 using adjusted Cox regression models. Results Of the 788 recipients followed for a median of 2.8 years (resulting in 2891 person-years), 321 (40.7%) and 467 (59.3%) received zero and one or two HLA-DQ mismatched kidneys, respectively. Compared with recipients who have received zero HLA-DQ mismatched kidneys, those who have received one or two HLA-DQ mismatched kidneys experienced greater numbers of any rejection (50 of 321 versus 117 of 467; P<0.01), late rejections (occurring >6 months post-transplant; 8 of 321 versus 27 of 467; P=0.03), and antibody-mediated rejections (AMRs; 12 of 321 versus 38 of 467; P=0.01). Compared with recipients of zero HLA-DQ mismatched kidneys, the adjusted hazard ratios for any and late rejections in recipients who had received one or two HLA-DQ mismatched kidneys were 1.54 (95% confidence interval [95% CI], 1.08 to 2.19) and 2.85 (95% CI, 1.05 to 7.75), respectively. HLA-DR was an effect modifier between HLA-DQ mismatches and AMR (P value for interaction =0.02), such that the association between HLA-DQ mismatches and AMR was statistically significant in those who have received one or two HLA-DR mismatched kidneys, with adjusted hazard ratio of 2.50 (95% CI, 1.05 to 5.94). Conclusions HLA-DQ mismatches are associated with acute rejection, independent of HLA-ABDR mismatches and initial immunosuppression. Clinicians should be aware of the potential importance of HLA-DQ matching in the assessment of immunologic risk in kidney transplant recipients. PMID:27034399

System and method for memory allocation in a multiclass memory system

DOEpatents

Loh, Gabriel; Meswani, Mitesh; Ignatowski, Michael; Nutter, Mark

2016-06-28

A system for memory allocation in a multiclass memory system includes a processor coupleable to a plurality of memories sharing a unified memory address space, and a library store to store a library of software functions. The processor identifies a type of a data structure in response to a memory allocation function call to the library for allocating memory to the data structure. Using the library, the processor allocates portions of the data structure among multiple memories of the multiclass memory system based on the type of the data structure.

Study on the effect of black cumin (Nigella sativa Linn.) on experimental renal ischemia-reperfusion injury in rats.

PubMed

Mousavi, Ghafour

2015-08-01

To evaluate the effect of Black cumin (Nigella sativa Linn.) pre-treatment on renal ischemia/reperfusion (I/R) induced injury in the rats. A total of 40 male Wistar rats were randomly allocated into five equal groups including Sham, I/R model and three I/R+ Black cumin (0.5, 1 and 2%)-treated groups. I/R groups' kidneys were subjected to 60 min of global ischemia at 37°C followed by 24 h of reperfusion. At the end of reperfusion period, the rats were euthanized. Superoxide dismutase, catalase and glutathione peroxidase activities as well as reduced glutathione and renal malondialdehyde contents were determined in renal tissues. Kidney function tests and histopathological examination were also performed. High serum creatinine, blood urea nitrogen and uric acid as well as malondialhehyde (MDA) levels, and low antioxidant enzyme activities were observed in I/R rats compared to the sham rats. Pre-treatment with Black cumin for three weeks prior to IR operation improved renal function and reduced I/R induced renal inflammation and oxidative injury. These biochemical observations were supported by histopathological test of kidney sections. Black cumin significantly prevented renal ischemia/reperfusion induced functional and histological injuries.

Protective effect of selenium on cisplatin induced nephrotoxicity: A double-blind controlled randomized clinical trial.

PubMed

Ghorbani, Ali; Omidvar, Bita; Parsi, Abazar

2013-04-01

Renal injury is common following cisplatin infusion. Some agents have been used to attenuate cisplatin nephrotoxicity. However, except hydration, none of them has been proved to be effective. In this study selenium as an antioxidant supplement was tested on cisplatin induced renal injury. 122 cancerous patients (85 male and 37 female; age range of 14 to 82 years old) were enrolled to receive chemotherapy regimens consisting cisplatin. They were allocated into two groups using a random number list . Investigators, patients and analyzers all, were blinded in allocation by using sealed opaque envelopes. Intervention group received a single 400 mcg selenium tablet and patients in control group took a placebo tablet which was similar with selenium preparation in color, weight, shape and taste. Primary end points were an increase in plasma creatinine above 1.5 mg/dl in men and 1.4mg/dl in women, or increase of plasma creatinine more than 50% from baseline or urine flow rate less than 0.5 ml/kg/h. Creatinine level was measured initially and on the 5th day after cisplatin therapy. There was no difference in cumulative dose of cisplatin between the groups (p=0.54). There were not evidences of acute renal failure (ARF) in cases. While, among placebo group, 7 patients had criteria of acute kidney injury. Conclusions :selenium could probably prevent cisplatin-induced acute kidney injury, when it is added to hydration therapy in cancerous patients.

Development of organ-specific donor risk indices.

PubMed

Akkina, Sanjeev K; Asrani, Sumeet K; Peng, Yi; Stock, Peter; Kim, W Ray; Israni, Ajay K

2012-04-01

Because of the shortage of deceased donor organs, transplant centers accept organs from marginal deceased donors, including older donors. Organ-specific donor risk indices have been developed to predict graft survival with various combinations of donor and recipient characteristics. Here we review the kidney donor risk index (KDRI) and the liver donor risk index (LDRI) and compare and contrast their strengths, limitations, and potential uses. The KDRI has a potential role in developing new kidney allocation algorithms. The LDRI allows a greater appreciation of the importance of donor factors, particularly for hepatitis C virus-positive recipients; as the donor risk index increases, the rates of allograft and patient survival among these recipients decrease disproportionately. The use of livers with high donor risk indices is associated with increased hospital costs that are independent of recipient risk factors, and the transplantation of livers with high donor risk indices into patients with Model for End-Stage Liver Disease scores < 15 is associated with lower allograft survival; the use of the LDRI has limited this practice. Significant regional variations in donor quality, as measured by the LDRI, remain in the United States. We also review other potential indices for liver transplantation, including donor-recipient matching and the retransplant donor risk index. Although substantial progress has been made in developing donor risk indices to objectively assess donor variables that affect transplant outcomes, continued efforts are warranted to improve these indices to enhance organ allocation policies and optimize allograft survival. Copyright © 2012 American Association for the Study of Liver Diseases.

Effect of an intensive nutrition intervention of a high protein and low glycemic-index diet on weight of kidney transplant recipients: study protocol for a randomized clinical trial.

PubMed

Pedrollo, Elis Forcellini; Nicoletto, Bruna Bellincanta; Carpes, Larissa Salomoni; de Freitas, Júlia de Melo Cardoso; Buboltz, Julia Roberta; Forte, Cristina Carra; Bauer, Andrea Carla; Manfro, Roberto Ceratti; Souza, Gabriela Corrêa; Leitão, Cristiane Bauermann

2017-09-06

Excessive weight gain is commonly observed within the first year after kidney transplantation and is associated with negative outcomes, such as graft loss and cardiovascular events. The purpose of this study is to evaluate the effect of a high protein and low glycemic-index diet on preventing weight gain after kidney transplantation. We designed a prospective, single-center, open-label, randomized controlled study to compare the efficacy of a high protein (1.3-1.4 g/kg/day) and low-glycemic index diet versus a conventional diet (0.8-1.0 g/kg/day of protein) on preventing weight gain after kidney transplantation. A total of 120 eligible patients 2 months after transplantation will be recruited. Patients with an estimated glomerular filtration rate through the modification of diet of renal disease (MDRD) formula < 30 mL/min/1.73 m 2 or urinary albumin excretion > 300 mg/24 h will be excluded. Patients' diets will be allocated through simple sequential randomization. Patients will be followed-up for 12 months with nine clinic appointments with a dietitian and the evaluations will include nutritional assessment (anthropometrics, body composition, and resting metabolic rate) and laboratory tests. The primary outcome is weight maintenance or body weight gain under 5% after 12 months. Secondary outcomes include body composition, resting metabolic rate, satiety sensation, kidney function, and other metabolic parameters. Diets with higher protein content and lower glycemic index may lead to weight loss because of higher satiety sensation. However, there is a concern about the association of high protein intake and kidney damage. Nevertheless, there is little evidence on the impact of high protein intake on long-term kidney function outcome. Therefore, we designed a study to test if a high protein diet with low-glycemic index will be an effective and safe nutritional intervention to prevent weight gain in kidney transplant patients. ClinicalTrials.gov identifier, NCT02883777 . Registered on 3 August 2016.

[Health management system in outpatient follow-up of kidney transplantation patients].

PubMed

Zhang, Hong; Xie, Jinliang; Yao, Hui; Liu, Ling; Tan, Jianwen; Geng, Chunmi

2014-07-01

To develop a health management system for outpatient follow-up of kidney transplant patients. Access 2010 database software was used to establish the health management system for kidney transplantation patients in Windows XP operating system. Database management and post-operation follow-up of the kidney transplantation patients were realized through 6 function modules including data input, data query, data printing, questionnaire survey, data export, and follow-up management. The system worked stably and reliably, and the data input was easy and fast. The query, the counting and printing were convenient. Health management system for patients after kidney transplantation not only reduces the work pressure of the follow-up staff, but also improves the efficiency of outpatient follow-up.

Autophagy and kidney inflammation

PubMed Central

Kimura, Tomonori; Isaka, Yoshitaka; Yoshimori, Tamotsu

2017-01-01

ABSTRACT Inflammation plays a pivotal role in pathophysiological processes of kidney diseases. Macroautophagy/autophagy plays multiple roles in inflammatory responses, and the regulation of inflammation by autophagy has great potential as a treatment for damaged kidneys. A growing body of evidence suggests autophagy protects kidney from versatile kidney inflammatory insults, including those that are acute, chronic, metabolic, and aging-related. It is noteworthy that, in kidney, mitophagy is active, and damaged lysosomes are removed by autophagy. In this mode, autophagy suppresses inflammation to protect the kidney. Systemic inflammation also affects the kidney via pro-inflammatory cytokines and infiltration of inflammatory cells, and autophagy also has a regulatory role in systemic inflammation. This review focuses on the roles of autophagy in kidney diseases and aging through inflammation, and discusses the potential usage of autophagy as an inflammatory modulator for the treatment of kidney diseases. PMID:28441075

Autophagy and kidney inflammation.

PubMed

Kimura, Tomonori; Isaka, Yoshitaka; Yoshimori, Tamotsu

2017-06-03

Inflammation plays a pivotal role in pathophysiological processes of kidney diseases. Macroautophagy/autophagy plays multiple roles in inflammatory responses, and the regulation of inflammation by autophagy has great potential as a treatment for damaged kidneys. A growing body of evidence suggests autophagy protects kidney from versatile kidney inflammatory insults, including those that are acute, chronic, metabolic, and aging-related. It is noteworthy that, in kidney, mitophagy is active, and damaged lysosomes are removed by autophagy. In this mode, autophagy suppresses inflammation to protect the kidney. Systemic inflammation also affects the kidney via pro-inflammatory cytokines and infiltration of inflammatory cells, and autophagy also has a regulatory role in systemic inflammation. This review focuses on the roles of autophagy in kidney diseases and aging through inflammation, and discusses the potential usage of autophagy as an inflammatory modulator for the treatment of kidney diseases.

Community-aware task allocation for social networked multiagent systems.

PubMed

Wang, Wanyuan; Jiang, Yichuan

2014-09-01

In this paper, we propose a novel community-aware task allocation model for social networked multiagent systems (SN-MASs), where the agent' cooperation domain is constrained in community and each agent can negotiate only with its intracommunity member agents. Under such community-aware scenarios, we prove that it remains NP-hard to maximize system overall profit. To solve this problem effectively, we present a heuristic algorithm that is composed of three phases: 1) task selection: select the desirable task to be allocated preferentially; 2) allocation to community: allocate the selected task to communities based on a significant task-first heuristics; and 3) allocation to agent: negotiate resources for the selected task based on a nonoverlap agent-first and breadth-first resource negotiation mechanism. Through the theoretical analyses and experiments, the advantages of our presented heuristic algorithm and community-aware task allocation model are validated. 1) Our presented heuristic algorithm performs very closely to the benchmark exponential brute-force optimal algorithm and the network flow-based greedy algorithm in terms of system overall profit in small-scale applications. Moreover, in the large-scale applications, the presented heuristic algorithm achieves approximately the same overall system profit, but significantly reduces the computational load compared with the greedy algorithm. 2) Our presented community-aware task allocation model reduces the system communication cost compared with the previous global-aware task allocation model and improves the system overall profit greatly compared with the previous local neighbor-aware task allocation model.

The role of sympathetic nervous system in the progression of chronic kidney disease in the era of catheter based sympathetic renal denervation.

PubMed

Petras, Dimitrios; Koutroutsos, Konstantinos; Kordalis, Athanasios; Tsioufis, Costas; Stefanadis, Christodoulos

2013-08-01

The kidney has been shown to be critically involved as both trigger and target of sympathetic nervous system overactivity in both experimental and clinical studies. Renal injury and ischemia, activation of renin angiotensin system and dysfunction of nitric oxide system have been implicated in adrenergic activation from kidney. Conversely, several lines of evidence suggest that sympathetic overactivity, through functional and morphological alterations in renal physiology and structure, may contribute to kidney injury and chronic kidney disease progression. Pharmacologic modulation of sympathetic nervous system activity has been found to have a blood pressure independent renoprotective effect. The inadequate normalization of sympathoexcitation by pharmacologic treatment asks for novel treatment options. Catheter based renal denervation targets selectively both efferent and afferent renal nerves and functionally denervates the kidney providing blood pressure reduction in clinical trials and renoprotection in experimental models by ameliorating the effects of excessive renal sympathetic drive. This review will focus on the role of sympathetic overactivity in the pathogenesis of kidney injury and CKD progression and will speculate on the effect of renal denervation to these conditions.

ExplorinG frailty and mild cognitive impairmEnt in kidney tRansplantation to predict biomedicAl, psychosocial and health cost outcomeS (GERAS): protocol of a nationwide prospective cohort study.

PubMed

Mauthner, Oliver; Claes, Veerle; Walston, Jeremy; Engberg, Sandra; Binet, Isabelle; Dickenmann, Michael; Golshayan, Déla; Hadaya, Karine; Huynh-Do, Uyen; Calciolari, Stefano; De Geest, Sabina

2017-03-01

To present the rationale, design and methodology of the GERAS project, which examines whether assessment of frailty and mild cognitive impairment could enhance risk prediction for biomedical, psychosocial outcomes and foster efficient resource allocation in kidney transplantation. For the burgeoning cohort of older patients considered for kidney transplantation, evidence gaps regarding frailty and mild cognitive impairment limit clinical decision-making and medical management. As known risk factors for 'hard' clinical outcomes in chronic illness, both require further study in transplantation. Integrating these and other bio-psychosocial factors into a comprehensive pre-transplant patient assessment will provide insights regarding economic implications and may improve risk prediction. A nation-wide multi-centre prospective cohort study nested in the Swiss Transplant Cohort Study. Our nationally representative convenience sample includes 250 adult kidney transplant recipients. Data sources include the Swiss Transplant Cohort Study and primary data collected at time of transplantation, 6 months, 1 and 2 years post-transplant via established measures (the Montreal Cognitive Assessment, Psychosocial Questionnaire, Fried Frailty Instrument and a blood analysis), investigator-developed instruments and datasets compiled by hospitals' management control units, sickness funds, the Swiss Federal Statistical Office and the European Renal Association. Descriptive, competing risk survival and mixed effects analyses will be performed. Research Ethics Committee approval was obtained in January 2016. This pioneering project jointly examines frailty and mild cognitive impairment from bio-psychosocial and health economic perspectives. Results may significantly inform risk prediction, care tailoring and resource optimization to improve health outcomes in the ageing kidney transplant cohort. © 2016 John Wiley & Sons Ltd.

Outcomes of Simultaneous Liver/Kidney (SLK) Transplants are Equivalent to Kidney Transplant Alone (KTA): A Preliminary Report

PubMed Central

Hanish, Steven I.; Samaniego, Milagros; Mezrich, Joshua D.; Foley, David P.; Leverson, Glen E.; Lorentzen, David F.; Sollinger, Hans W.; Pirsch, John D.; D’Alessandro, Anthony M.; Fernandez, Luis A.

2011-01-01

Background With adoption of Model for End-stage Liver Disease (MELD), the number of simultaneous liver-kidney transplants (SLK) has greatly increased. A recent registry study questioned the equity of allocating kidney transplants (KTx) simultaneously with liver transplantation due to poor outcomes (1). Methods To investigate outcome of KTx in SLK, all SLK (n=36) performed at our center from 1/2000–12/2007 were reviewed and KTx outcomes compared to those of kidney transplant alone (KTA) performed during that period (n=1,283). We also reviewed whether pre-transplant panel reactive antibody (PRA) and donor specific antibody (DSA) affected KTx outcome in SLK. Results One- and three-year KTx and patient survival were not different between KTA and SLK regardless of sensitization level. There were 348 (27%) KTx failures in KTA vs. 6 (17%) in SLK (NS). Overall freedom from acute cellular rejection (ACR) and antibody-mediated rejection (AMR) in SLK was 93% and 96% at 3 years, compared to 72% and 78% in KTA (p=0.0105 and p=0.0744, respectively). Sensitized KTx recipients had more ACR and AMR (32% and 38%) at three years compared to non-sensitized recipients (28% and 20%) (p=0.23 and 0.0001, respectively). No differences in ACR and AMR were observed when SLK was divided and level of sensitization compared (p=0.17 and 0.65, respectively). Conclusion SLK is a life-saving procedure with excellent patient and graft survival. AMR incidence in the KTx appears reduced in SLK compared to KTA regardless of level of preoperative PRA. A high level of DSA should not preclude simultaneous transplantation when clinically indicated. PMID:20626084

Calculation and application of energy transaction allocation factors in electric power transmission systems

NASA Astrophysics Data System (ADS)

Fradi, Aniss

The ability to allocate the active power (MW) loading on transmission lines and transformers, is the basis of the "flow based" transmission allocation system developed by the North American Electric Reliability Council. In such a system, the active power flows must be allocated to each line or transformer in proportion to the active power being transmitted by each transaction imposed on the system. Currently, this is accomplished through the use of the linear Power Transfer Distribution Factors (PTDFs). Unfortunately, no linear allocation models exist for other energy transmission quantities, such as MW and MVAR losses, MVAR and MVA flows, etc. Early allocation schemes were developed to allocate MW losses due to transactions to branches in a transmission system, however they exhibited diminished accuracy, since most of them are based on linear power flow modeling of the transmission system. This thesis presents a new methodology to calculate Energy Transaction Allocation factors (ETA factors, or eta factors), using the well-known process of integration of a first derivative function, as well as consistent and well-established mathematical and AC power flow models. The factors give a highly accurate allocation of any non-linear system quantity to transactions placed on the transmission system. The thesis also extends the new ETA factors calculation procedure to restructure a new economic dispatch scheme where multiple sets of generators are economically dispatched to meet their corresponding load and their share of the losses.

Associations between Deceased-Donor Urine Injury Biomarkers and Kidney Transplant Outcomes

PubMed Central

Reese, Peter P.; Hall, Isaac E.; Weng, Francis L.; Schröppel, Bernd; Doshi, Mona D.; Hasz, Rick D.; Thiessen-Philbrook, Heather; Ficek, Joseph; Rao, Veena; Murray, Patrick; Lin, Haiqun

2016-01-01

Assessment of deceased-donor organ quality is integral to transplant allocation practices, but tools to more precisely measure donor kidney injury and better predict outcomes are needed. In this study, we assessed associations between injury biomarkers in deceased-donor urine and the following outcomes: donor AKI (stage 2 or greater), recipient delayed graft function (defined as dialysis in first week post-transplant), and recipient 6-month eGFR. We measured urinary concentrations of microalbumin, neutrophil gelatinase–associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), IL-18, and liver-type fatty acid binding protein (L-FABP) from 1304 deceased donors at organ procurement, among whom 112 (9%) had AKI. Each biomarker strongly associated with AKI in adjusted analyses. Among 2441 kidney transplant recipients, 31% experienced delayed graft function, and mean±SD 6-month eGFR was 55.7±23.5 ml/min per 1.73 m2. In analyses adjusted for donor and recipient characteristics, higher donor urinary NGAL concentrations associated with recipient delayed graft function (highest versus lowest NGAL tertile relative risk, 1.21; 95% confidence interval, 1.02 to 1.43). Linear regression analyses of 6-month recipient renal function demonstrated that higher urinary NGAL and L-FABP concentrations associated with slightly lower 6-month eGFR only among recipients without delayed graft function. In summary, donor urine injury biomarkers strongly associate with donor AKI but provide limited value in predicting delayed graft function or early allograft function after transplant. PMID:26374609

Advances in liver transplantation allocation systems.

PubMed

Schilsky, Michael L; Moini, Maryam

2016-03-14

With the growing number of patients in need of liver transplantation, there is a need for adopting new and modifying existing allocation policies that prioritize patients for liver transplantation. Policy should ensure fair allocation that is reproducible and strongly predictive of best pre and post transplant outcomes while taking into account the natural history of the potential recipients liver disease and its complications. There is wide acceptance for allocation policies based on urgency in which the sickest patients on the waiting list with the highest risk of mortality receive priority. Model for end-stage liver disease and Child-Turcotte-Pugh scoring system, the two most universally applicable systems are used in urgency-based prioritization. However, other factors must be considered to achieve optimal allocation. Factors affecting pre-transplant patient survival and the quality of the donor organ also affect outcome. The optimal system should have allocation prioritization that accounts for both urgency and transplant outcome. We reviewed past and current liver allocation systems with the aim of generating further discussion about improvement of current policies.

Extended criteria donor kidney transplantation: comparative outcome analysis between single versus double kidney transplantation at 5 years.

PubMed

Lucarelli, G; Bettocchi, C; Battaglia, M; Impedovo, S V; Vavallo, A; Grandaliano, G; Castellano, G; Schena, F P; Selvaggi, F P; Ditonno, P

2010-05-01

Dual kidney transplantation (DKT), using extended criteria donor (ECD) grafts not suitable for single kidney transplantation (SKT), has been suggested to expand the kidney donor pool. Herein, we reviewed the long-term outcomes of DKT to assess its results versus a control group of 179 ECD SKTs. The allocation policy was based on a Remuzzi score obtained from a pretransplant biopsy. We analyzed SKT in 179 (31.8%) and DKT in 41 (7.3%) of 563 cadaveric transplants from 2000 to 2008. Patients with DKT versus SKT showed mean recipient ages of 54 versus 51 years. We performed 17 ipsilateral and 24 bilateral DKT. The mean score was 2.78 for SKT and 4.3/4.6 for DKT. Delayed graft function requiring dialysis occurred in 23 (56.1%) DKT and 70 (39.1%) SKT recipients. Primary nonfunction was observed in 1 (2.4%) DKT and 7 (3.9%) SKT recipients respectively. One DKT patient underwent monolateral transplantectomy. In the DKT versus SKT group, patient survivals were 92% versus 95%, 89% versus 93%, and 89 versus 91% at 12, 36, and 60 months, respectively (P = .3). Graft survivals were 100% versus 94%, 95% versus 90%, and 89% versus 78% at 12, 36, and 60 months, respectively (P < .001). We observed a lower incidence of chronic allograft nephropathy (P = .01) and a higher incidence of surgical adverse events (P = .04) in DKT. ECD graft survival using DKT provided better results compared with SKT, despite the use of organs from higher-risk donors. At 5 years follow-up, DKT was a safe strategy to face the organ shortage. To optimize the use of available kidneys, the criteria for DKT require further refinement and standardization. Preimplantation evaluation must maximize transplant success and protect recipients from receiving organs at increased risk of premature failure. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Rate Adaptive Based Resource Allocation with Proportional Fairness Constraints in OFDMA Systems

PubMed Central

Yin, Zhendong; Zhuang, Shufeng; Wu, Zhilu; Ma, Bo

2015-01-01

Orthogonal frequency division multiple access (OFDMA), which is widely used in the wireless sensor networks, allows different users to obtain different subcarriers according to their subchannel gains. Therefore, how to assign subcarriers and power to different users to achieve a high system sum rate is an important research area in OFDMA systems. In this paper, the focus of study is on the rate adaptive (RA) based resource allocation with proportional fairness constraints. Since the resource allocation is a NP-hard and non-convex optimization problem, a new efficient resource allocation algorithm ACO-SPA is proposed, which combines ant colony optimization (ACO) and suboptimal power allocation (SPA). To reduce the computational complexity, the optimization problem of resource allocation in OFDMA systems is separated into two steps. For the first one, the ant colony optimization algorithm is performed to solve the subcarrier allocation. Then, the suboptimal power allocation algorithm is developed with strict proportional fairness, and the algorithm is based on the principle that the sums of power and the reciprocal of channel-to-noise ratio for each user in different subchannels are equal. To support it, plenty of simulation results are presented. In contrast with root-finding and linear methods, the proposed method provides better performance in solving the proportional resource allocation problem in OFDMA systems. PMID:26426016

A computer-aided diagnostic system for kidney disease

PubMed Central

Jahantigh, Farzad Firouzi; Malmir, Behnam; Avilaq, Behzad Aslani

2017-01-01

Background Disease diagnosis is complicated since patients may demonstrate similar symptoms but physician may diagnose different diseases. There are a few number of investigations aimed to create a fuzzy expert system, as a computer aided system for disease diagnosis. Methods In this research, a cross-sectional descriptive study conducted in a kidney clinic in Tehran, Iran in 2012. Medical diagnosis fuzzy rules applied, and a set of symptoms related to the set of considered diseases defined. The input case to be diagnosed defined by assigning a fuzzy value to each symptom and then three physicians asked about each suspected diseases. Then comments of those three physicians summarized for each disease. The fuzzy inference applied to obtain a decision fuzzy set for each disease, and crisp decision values attained to determine the certainty of existence for each disease. Results Results indicated that, in the diagnosis of seven cases of kidney disease by examining 21 indicators using fuzzy expert system, kidney stone disease with 63% certainty was the most probable, renal tubular was at the lowest level with 15%, and other kidney diseases were at the other levels. The most remarkable finding of this study was that results of kidney disease diagnosis (e.g., kidney stone) via fuzzy expert system were fully compatible with those of kidney physicians. Conclusion The proposed fuzzy expert system is a valid, reliable, and flexible instrument to diagnose several typical input cases. The developed system decreases the effort of initial physical checking and manual feeding of input symptoms. PMID:28392995

A computer-aided diagnostic system for kidney disease.

PubMed

Jahantigh, Farzad Firouzi; Malmir, Behnam; Avilaq, Behzad Aslani

2017-03-01

Disease diagnosis is complicated since patients may demonstrate similar symptoms but physician may diagnose different diseases. There are a few number of investigations aimed to create a fuzzy expert system, as a computer aided system for disease diagnosis. In this research, a cross-sectional descriptive study conducted in a kidney clinic in Tehran, Iran in 2012. Medical diagnosis fuzzy rules applied, and a set of symptoms related to the set of considered diseases defined. The input case to be diagnosed defined by assigning a fuzzy value to each symptom and then three physicians asked about each suspected diseases. Then comments of those three physicians summarized for each disease. The fuzzy inference applied to obtain a decision fuzzy set for each disease, and crisp decision values attained to determine the certainty of existence for each disease. Results indicated that, in the diagnosis of seven cases of kidney disease by examining 21 indicators using fuzzy expert system, kidney stone disease with 63% certainty was the most probable, renal tubular was at the lowest level with 15%, and other kidney diseases were at the other levels. The most remarkable finding of this study was that results of kidney disease diagnosis (e.g., kidney stone) via fuzzy expert system were fully compatible with those of kidney physicians. The proposed fuzzy expert system is a valid, reliable, and flexible instrument to diagnose several typical input cases. The developed system decreases the effort of initial physical checking and manual feeding of input symptoms.

47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

Code of Federal Regulations, 2010 CFR

2010-10-01

...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. 25...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. Licensees of non-geostationary satellite systems that use frequency bands allocated to the fixed-satellite...

47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

Code of Federal Regulations, 2012 CFR

2012-10-01

...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. 25...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. Licensees of non-geostationary satellite systems that use frequency bands allocated to the fixed-satellite...

47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

Code of Federal Regulations, 2014 CFR

2014-10-01

...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. 25...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. Licensees of non-geostationary satellite systems that use frequency bands allocated to the Fixed-Satellite...

47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

Code of Federal Regulations, 2011 CFR

2011-10-01

...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. 25...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. Licensees of non-geostationary satellite systems that use frequency bands allocated to the fixed-satellite...

47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

Code of Federal Regulations, 2013 CFR

2013-10-01

...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. 25...-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. Licensees of non-geostationary satellite systems that use frequency bands allocated to the Fixed-Satellite...

Evolving Reliability and Maintainability Allocations for NASA Ground Systems

NASA Technical Reports Server (NTRS)

Munoz, Gisela; Toon, Jamie; Toon, Troy; Adams, Timothy C.; Miranda, David J.

2016-01-01

This paper describes the methodology that was developed to allocate reliability and maintainability requirements for the NASA Ground Systems Development and Operations (GSDO) program's subsystems. As systems progressed through their design life cycle and hardware data became available, it became necessary to reexamine the previously derived allocations. Allocating is an iterative process; as systems moved beyond their conceptual and preliminary design phases this provided an opportunity for the reliability engineering team to reevaluate allocations based on updated designs and maintainability characteristics of the components. Trade-offs in reliability and maintainability were essential to ensuring the integrity of the reliability and maintainability analysis. This paper will discuss the value of modifying reliability and maintainability allocations made for the GSDO subsystems as the program nears the end of its design phase.

Immune System and Kidney Transplantation.

PubMed

Shrestha, Badri Man

2017-01-01

The immune system recognises a transplanted kidney as foreign body and mounts immune response through cellular and humoral mechanisms leading to acute or chronic rejection, which ultimately results in graft loss. Over the last five decades, there have been significant advances in the understanding of the immune responses to transplanted organs in both experimental and clinical transplant settings. Modulation of the immune response by using immunosuppressive agents has led to successful outcomes after kidney transplantation. The paper provides an overview of the general organisation and function of human immune system, immune response to kidney transplantation, and the current practice of immunosuppressive therapy in kidney transplantation in the United Kingdom.

Factors influencing resource allocation decisions and equity in the health system of Ghana.

PubMed

Asante, A D; Zwi, A B

2009-05-01

Allocation of financial resources in the health sector is often seen as a formula-driven activity. However, the decision to allocate a certain amount of resources to a particular health jurisdiction or facility may be based on a broader range of factors, sometimes not reflected in the existing resource allocation formula. This study explores the 'other' factors that influence the equity of resource allocation in the health system of Ghana. The extent to which these factors are, or can be, accounted for in the resource allocation process is analysed. An exploratory design focusing on different levels of the health system and diverse stakeholders. Data were gathered through semi-structured qualitative interviews with health authorities at national, regional and district levels, and with donor representatives and local government officials in 2003 and 2004. The availability of human resources for health, local capacity to utilize funds, donor involvement in the health sector, and commitment to promote equity have considerable influence on resource allocation decisions and affect the equity of funding allocations. However, these factors are not accounted for adequately in the resource allocation process. This study highlights the need for a more transparent resource allocation system in Ghana based on needs, and takes into account key issues such as capacity constraints, the inequitable human resource distribution and donor-earmarked funding.

Serum Phosphorus and Risk of Cardiovascular Disease, All-Cause Mortality, or Graft Failure in Kidney Transplant Recipients: An Ancillary Study of the FAVORIT Trial Cohort.

PubMed

Merhi, Basma; Shireman, Theresa; Carpenter, Myra A; Kusek, John W; Jacques, Paul; Pfeffer, Marc; Rao, Madhumathi; Foster, Meredith C; Kim, S Joseph; Pesavento, Todd E; Smith, Stephen R; Kew, Clifton E; House, Andrew A; Gohh, Reginald; Weiner, Daniel E; Levey, Andrew S; Ix, Joachim H; Bostom, Andrew

2017-09-01

Mild hyperphosphatemia is a putative risk factor for cardiovascular disease [CVD], loss of kidney function, and mortality. Very limited data are available from sizable multicenter kidney transplant recipient (KTR) cohorts assessing the potential relationships between serum phosphorus levels and the development of CVD outcomes, transplant failure, or all-cause mortality. Cohort study. The Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) Trial, a large, multicenter, multiethnic, controlled clinical trial that provided definitive evidence that high-dose vitamin B-based lowering of plasma homocysteine levels did not reduce CVD events, transplant failure, or total mortality in stable KTRs. Serum phosphorus levels were determined in 3,138 FAVORIT trial participants at randomization. During a median follow-up of 4.0 years, the cohort had 436 CVD events, 238 transplant failures, and 348 deaths. Proportional hazards modeling revealed that each 1-mg/dL higher serum phosphorus level was not associated with a significant increase in CVD risk (HR, 1.06; 95% CI, 0.92-1.22), but increased transplant failure (HR, 1.36; 95% CI, 1.15-1.62) and total mortality risk associations (HR, 1.21; 95% CI, 1.04-1.40) when adjusted for treatment allocation, traditional CVD risk factors, kidney measures, type of kidney transplant, transplant vintage, and use of calcineurin inhibitors, steroids, or lipid-lowering drugs. These associations were strengthened in models without kidney measures: CVD (HR, 1.14; 95% CI, 1.00-1.31), transplant failure (HR, 1.72; 95% CI, 1.46-2.01), and mortality (HR, 1.34; 95% CI, 1.15-1.54). We lacked data for concentrations of parathyroid hormone, fibroblast growth factor 23, or vitamin D metabolites. Serum phosphorus level is marginally associated with CVD and more strongly associated with transplant failure and total mortality in long-term KTRs. A randomized controlled clinical trial in KTRs that assesses the potential impact of phosphorus-lowering therapy on these hard outcomes may be warranted. Copyright © 2017 National Kidney Foundation, Inc. All rights reserved.

A developmentally plastic adult mouse kidney cell line spontaneously generates multiple adult kidney structures

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

Webb, Carol F., E-mail: carol-webb@omrf.org; Immunobiology and Cancer Research, Oklahoma Medical Research Foundation, Oklahoma City, OK; Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK

Despite exciting new possibilities for regenerative therapy posed by the ability to induce pluripotent stem cells, recapitulation of three-dimensional kidneys for repair or replacement has not been possible. ARID3a-deficient mouse tissues generated multipotent, developmentally plastic cells. Therefore, we assessed the adult mouse ARID3a−/− kidney cell line, KKPS5, which expresses renal progenitor surface markers as an alternative cell source for modeling kidney development. Remarkably, these cells spontaneously developed into multicellular nephron-like structures in vitro, and engrafted into immunocompromised medaka mesonephros, where they formed mouse nephron structures. These data implicate KKPS5 cells as a new model system for studying kidney development. - Highlights:more » • An ARID3a-deficient mouse kidney cell line expresses multiple progenitor markers. • This cell line spontaneously forms multiple nephron-like structures in vitro. • This cell line formed mouse kidney structures in immunocompromised medaka fish kidneys. • Our data identify a novel model system for studying kidney development.« less

Osthole ameliorates renal ischemia-reperfusion injury by inhibiting inflammatory response.

PubMed

Zheng, Yi; Lu, Min; Ma, Lulin; Zhang, Shudong; Qiu, Min; Ma, Xin

2013-01-01

Renal ischemia-reperfusion (I/R) injury is a primary cause of acute renal failure that results in high mortality. This study aimed to investigate the effect of osthole, a natural coumarin derivative, on renal I/R injury in a rat model. Rats were randomly allocated to the sham operation + vehicle, I/R + vehicle, and I/R + osthole groups. Renal I/R injury was induced by clamping the left renal artery for 45 min followed by 12 h of reperfusion and a contralateral nephrectomy. Osthole (40 mg/kg) was intraperitoneally injected 30 min before inducing I/R. Renal function and histological damage were determined subsequently. Myeloperoxidase activity, monocyte/macrophage infiltration, as well as tumor necrosis factor-α, IL-1β, and activated p38 mitogen-activated protein kinase expression in kidneys were also assessed. Osthole treatment significantly ameliorated I/R-induced renal functional and morphological injuries. Moreover, osthole treatment attenuated myeloperoxidase activity, monocyte/macrophage infiltration, and tumor necrosis factor-α, IL-1β, and activated p38 mitogen-activated protein kinase expression in kidneys. Osthole treatment ameliorates renal I/R injury by inhibiting inflammatory responses in kidneys. Thus, osthole may represent a novel practical strategy to prevent renal I/R injury. Copyright © 2013 S. Karger AG, Basel.

Kidney donation and transplantation in the UK from 1998 to 2007.

PubMed

Johnson, Rachel; Collett, Dave; Birch, Rhiannon; Fuggle, Susan; Rudge, Chris

2008-01-01

There are many changes happening in donation and transplantation in the UK and this review provides a baseline against which the success of future developments can be assessed. There has been a decrease in donation after brain death over the 10-year review period, but increases in both donation after cardiac death and living kidney donation. Antibody incompatible transplantation and paired and altruistic donation programmes are starting to have an impact on the number of living donor transplants carried out and are expected to make a more marked impact in the years ahead. A new national Kidney Allocation Scheme for deceased donors after brain death was introduced in 2006 to replace the previous scheme implemented in 1998. The 2006 scheme aims to improve equity of access to transplant and is showing significant benefits for long-waiting patients. To ensure that all UK transplant centres continue to achieve high standards, both within- and across-centre monitoring of graft and patient outcomes is routinely undertaken and reported. The most important factor in increasing organ donation and transplantation in the UK is the government funding that has been provided to develop national organ donation infrastructures. These major changes are expected to have a significant impact on numbers of donors and transplants in the next 5 years.

Strengthening Renal Registries and ESRD Research in Africa.

PubMed

Davids, M Razeen; Caskey, Fergus J; Young, Taryn; Balbir Singh, Gillian K

2017-05-01

In Africa, the combination of noncommunicable diseases, infectious diseases, exposure to environmental toxins, and acute kidney injury related to trauma and childbirth are driving an epidemic of chronic kidney disease and end-stage renal disease (ESRD). Good registry data can inform the planning of renal services and can be used to argue for better resource allocation, audit the delivery and quality of care, and monitor the impact of interventions. Few African countries have established renal registries and most have failed owing to resource constraints. In this article we briefly review the burden of chronic kidney disease and ESRD in Africa, and then consider the research questions that could be addressed by renal registries. We describe examples of the impact of registry data and summarize the sparse primary literature on country-wide renal replacement therapy in African countries over the past 20 years. Finally, we highlight some initiatives and opportunities for strengthening research on ESRD and renal replacement therapy in Africa. These include the establishment of the African Renal Registry and the availability of new areas for research. We also discuss capacity building, collaboration, open-access publication, and the strengthening of local journals, all measures that may improve the quantity, visibility, and impact of African research outputs. Copyright © 2017 Elsevier Inc. All rights reserved.

Evolution of Acute Kidney Injury and Its Association With Systemic Hemodynamics in Children With Fluid-Refractory Septic Shock.

PubMed

Deep, Akash; Sagar, Hiremath; Goonasekera, Chulananda; Karthikeyan, Palaniswamy; Brierley, Joe; Douiri, Abdel

2018-07-01

There are no studies in pediatrics evaluating the progression of acute kidney injury in septic shock. We investigated the evolution of sepsis-associated acute kidney injury and its association with systemic hemodynamics in children with fluid-refractory septic shock. Prospective cohort study. PICU of a tertiary care hospital. All patients with fluid-refractory septic shock (n = 61) between September 2010 and February 2014. Hemodynamic variables using noninvasive ultrasound cardiac output monitor were measured at admission and 6 hourly thereafter till 48 hours. We used the Kidney Disease: Improving Global Outcomes criteria to define and stage acute kidney injury. Associations between various hemodynamic variables and development of acute kidney injury were evaluated. Severe acute kidney injury was defined as stage 2 or 3 acute kidney injury and was compared with no acute kidney injury or stage 1 acute kidney injury. Severe acute kidney injury developed in 29.5% (n = 18) of the 61 children with fluid-refractory septic shock, whereas 43 patients (70.49%) had either no or stage 1 acute kidney injury. Most patients who developed acute kidney injury did so within the first 48 hours of PICU admission. Severe acute kidney injury conferred a three-fold increased risk of death by day 28 (hazard ratio, 3.23; 95% CI, 1.52-6.67; p = 0.002), longer ICU stay, and increased duration of mechanical ventilation. Central venous pressure at presentation was higher in severe acute kidney injury by 5 cm H2O. Highest lactate in the first 24 hours of PICU admission, low diastolic blood pressure, low systemic vascular resistance index at admission were associated with severe acute kidney injury. This model reliably predicted stage 2/3 acute kidney injury by day 3 with area under the curve equals to 94%; 95% CI, 88.3-99.99. None of the other hemodynamic variables showed any association with severe acute kidney injury. Manifestations of sepsis-associated acute kidney injury often occur early after PICU admission and is associated with increased morbidity and mortality. There is a need to develop a predictive model in septic shock which could facilitate early detection of acute kidney injury.

Comparative reproductive and physiological responses of northern bobwhite and scaled quail to water deprivation

USGS Publications Warehouse

Giuliano, W.M.; Patino, R.; Lutz, R.S.

1998-01-01

We compared reproductive and physiological responses of captive female northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) under control and water deprivation conditions. Scaled quail required less food and water to reproduce successfully under control conditions than northern bobwhite. Additionally, in scaled quail, serum osmolality levels and kidney mass were unaffected by water deprivation, whereas in northern bobwhite, serum osmolality levels increased and kidney mass declined. This finding indicates that scaled quail may have osmoregulatory abilities superior to those of northern bobwhite. Under control conditions, northern bobwhite gained more body mass and produced more but smaller eggs than scaled quail. Under water deprivation conditions, northern bobwhite lost more body mass but had more laying hens with a higher rate of egg production than scaled quail. Our data suggest that northern bobwhite allocated more resources to reproduction than to body maintenance, while scaled quail apparently forego reproduction in favor of body maintenance during water deprivation conditions.

Utility of HLA Antibody Testing in Kidney Transplantation

PubMed Central

Konvalinka, Ana

2015-01-01

HLA antigens are polymorphic proteins expressed on donor kidney allograft endothelium and are critical targets for recipient immune recognition. HLA antibodies are risk factors for acute and chronic rejection and allograft loss. Solid-phase immunoassays for HLA antibody detection represent a major advance in sensitivity and specificity over cell-based methods and are widely used in organ allocation and pretransplant risk assessment. Post-transplant, development of de novo donor–specific HLA antibodies and/or increase in donor-specific antibodies from pretransplant levels are associated with adverse outcomes. Although single antigen bead assays have allowed sensitive detection of recipient HLA antibodies and their specificities, a number of interpretive considerations must be appreciated to understand test results in clinical and research contexts. This review, which is especially relevant for clinicians caring for transplant patients, discusses the technical aspects of single antigen bead assays, emphasizes their quantitative limitations, and explores the utility of HLA antibody testing in identifying and managing important pre- and post-transplant clinical outcomes. PMID:25804279

Human-Automation Allocations for Current Robotic Space Operations

NASA Technical Reports Server (NTRS)

Marquez, Jessica J.; Chang, Mai L.; Beard, Bettina L.; Kim, Yun Kyung; Karasinski, John A.

2018-01-01

Within the Human Research Program, one risk delineates the uncertainty surrounding crew working with automation and robotics in spaceflight. The Risk of Inadequate Design of Human and Automation/Robotic Integration (HARI) is concerned with the detrimental effects on crew performance due to ineffective user interfaces, system designs and/or functional task allocation, potentially compromising mission success and safety. Risk arises because we have limited experience with complex automation and robotics. One key gap within HARI, is the gap related to functional allocation. The gap states: We need to evaluate, develop, and validate methods and guidelines for identifying human-automation/robot task information needs, function allocation, and team composition for future long duration, long distance space missions. Allocations determine the human-system performance as it identifies the functions and performance levels required by the automation/robotic system, and in turn, what work the crew is expected to perform and the necessary human performance requirements. Allocations must take into account each of the human, automation, and robotic systems capabilities and limitations. Some functions may be intuitively assigned to the human versus the robot, but to optimize efficiency and effectiveness, purposeful role assignments will be required. The role of automation and robotics will significantly change in future exploration missions, particularly as crew becomes more autonomous from ground controllers. Thus, we must understand the suitability of existing function allocation methods within NASA as well as the existing allocations established by the few robotic systems that are operational in spaceflight. In order to evaluate future methods of robotic allocations, we must first benchmark the allocations and allocation methods that have been used. We will present 1) documentation of human-automation-robotic allocations in existing, operational spaceflight systems; and 2) To gather existing lessons learned and best practices in these role assignments, from spaceflight operational experience of crew and ground teams that may be used to guide development for future systems. NASA and other space agencies have operational spaceflight experience with two key Human-Automation-Robotic (HAR) systems: heavy lift robotic arms and planetary robotic explorers. Additionally, NASA has invested in high-fidelity rover systems that can carry crew, building beyond Apollo's lunar rover. The heavy lift robotic arms reviewed are: Space Station Remote Manipulator System (SSRMS), Japanese Remote Manipulator System (JEMRMS), and the European Robotic Arm (ERA, designed but not deployed in space). The robotic rover systems reviewed are: Mars Exploration Rovers, Mars Science Laboratory rover, and the high-fidelity K10 rovers. Much of the design and operational feedback for these systems have been communicated to flight controllers and robotic design teams. As part of the mitigating the HARI risk for future human spaceflight operations, we must document function allocations between robots and humans that have worked well in practice.

Resource allocation and budgetary mechanisms for decentralized health systems: experiences from Balochistan, Pakistan.

PubMed

Green, A; Ali, B; Naeem, A; Ross, D

2000-01-01

This paper identifies key political and technical issues involved in the development of an appropriate resource allocation and budgetary system for the public health sector, using experience gained in the Province of Balochistan, Pakistan. The resource allocation and budgetary system is a critical, yet often neglected, component of any decentralization policy. Current systems are often based on historical incrementalism that is neither efficient nor equitable. This article describes technical work carried out in Balochistan to develop a system of resource allocation and budgeting that is needs-based, in line with policies of decentralization, and implementable within existing technical constraints. However, the development of technical systems, while necessary, is not a sufficient condition for the implementation of a resource allocation and decentralized budgeting system. This is illustrated by analysing the constraints that have been encountered in the development of such a system in Balochistan.

Resource allocation and budgetary mechanisms for decentralized health systems: experiences from Balochistan, Pakistan.

PubMed Central

Green, A.; Ali, B.; Naeem, A.; Ross, D.

2000-01-01

This paper identifies key political and technical issues involved in the development of an appropriate resource allocation and budgetary system for the public health sector, using experience gained in the Province of Balochistan, Pakistan. The resource allocation and budgetary system is a critical, yet often neglected, component of any decentralization policy. Current systems are often based on historical incrementalism that is neither efficient nor equitable. This article describes technical work carried out in Balochistan to develop a system of resource allocation and budgeting that is needs-based, in line with policies of decentralization, and implementable within existing technical constraints. However, the development of technical systems, while necessary, is not a sufficient condition for the implementation of a resource allocation and decentralized budgeting system. This is illustrated by analysing the constraints that have been encountered in the development of such a system in Balochistan. PMID:10994286

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

Hussain, Hameed; Malik, Saif Ur Rehman; Hameed, Abdul

An efficient resource allocation is a fundamental requirement in high performance computing (HPC) systems. Many projects are dedicated to large-scale distributed computing systems that have designed and developed resource allocation mechanisms with a variety of architectures and services. In our study, through analysis, a comprehensive survey for describing resource allocation in various HPCs is reported. The aim of the work is to aggregate under a joint framework, the existing solutions for HPC to provide a thorough analysis and characteristics of the resource management and allocation strategies. Resource allocation mechanisms and strategies play a vital role towards the performance improvement ofmore » all the HPCs classifications. Therefore, a comprehensive discussion of widely used resource allocation strategies deployed in HPC environment is required, which is one of the motivations of this survey. Moreover, we have classified the HPC systems into three broad categories, namely: (a) cluster, (b) grid, and (c) cloud systems and define the characteristics of each class by extracting sets of common attributes. All of the aforementioned systems are cataloged into pure software and hybrid/hardware solutions. The system classification is used to identify approaches followed by the implementation of existing resource allocation strategies that are widely presented in the literature.« less

49 CFR 33.54 - Elements of an allocation order.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 1 2014-10-01 2014-10-01 false Elements of an allocation order. 33.54 Section 33.54 Transportation Office of the Secretary of Transportation TRANSPORTATION PRIORITIES AND ALLOCATION SYSTEM Allocation Actions § 33.54 Elements of an allocation order. Each allocation order must include: (a...

49 CFR 33.54 - Elements of an allocation order.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 1 2012-10-01 2012-10-01 false Elements of an allocation order. 33.54 Section 33.54 Transportation Office of the Secretary of Transportation TRANSPORTATION PRIORITIES AND ALLOCATION SYSTEM Allocation Actions § 33.54 Elements of an allocation order. Each allocation order must include: (a...

49 CFR 33.54 - Elements of an allocation order.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 1 2013-10-01 2013-10-01 false Elements of an allocation order. 33.54 Section 33.54 Transportation Office of the Secretary of Transportation TRANSPORTATION PRIORITIES AND ALLOCATION SYSTEM Allocation Actions § 33.54 Elements of an allocation order. Each allocation order must include: (a...

An Analysis and Allocation System for Library Collections Budgets: The Comprehensive Allocation Process (CAP)

ERIC Educational Resources Information Center

Lyons, Lucy Eleonore; Blosser, John

2012-01-01

The "Comprehensive Allocation Process" (CAP) is a reproducible decision-making structure for the allocation of new collections funds, for the reallocation of funds within stagnant budgets, and for budget cuts in the face of reduced funding levels. This system was designed to overcome common shortcomings of current methods. Its philosophical…

A pollutant load hierarchical allocation method integrated in an environmental capacity management system for Zhushan Bay, Taihu Lake.

PubMed

Liang, Shidong; Jia, Haifeng; Yang, Cong; Melching, Charles; Yuan, Yongping

2015-11-15

An environmental capacity management (ECM) system was developed to help practically implement a Total Maximum Daily Load (TMDL) for a key bay in a highly eutrophic lake in China. The ECM system consists of a simulation platform for pollutant load calculation and a pollutant load hierarchical allocation (PLHA) system. The simulation platform was developed by linking the Environmental Fluid Dynamics Code (EFDC) and Water Quality Analysis Simulation Program (WASP). In the PLHA, pollutant loads were allocated top-down in several levels based on characteristics of the pollutant sources. Different allocation methods could be used for the different levels with the advantages of each method combined over the entire allocation. Zhushan Bay of Taihu Lake, one of the most eutrophic lakes in China, was selected as a case study. The allowable loads of total nitrogen, total phosphorus, ammonia, and chemical oxygen demand were found to be 2122.2, 94.9, 1230.4, and 5260.0 t·yr(-1), respectively. The PLHA for the case study consists of 5 levels. At level 0, loads are allocated to those from the lakeshore direct drainage, atmospheric deposition, internal release, and tributary inflows. At level 1 the loads allocated to tributary inflows are allocated to the 3 tributaries. At level 2, the loads allocated to one inflow tributary are allocated to upstream areas and local sources along the tributary. At level 3, the loads allocated to local sources are allocated to the point and non-point sources from different towns. At level 4, the loads allocated to non-point sources in each town are allocated to different villages. Compared with traditional forms of pollutant load allocation methods, PLHA can combine the advantages of different methods which put different priority weights on equity and efficiency, and the PLHA is easy to understand for stakeholders and more flexible to adjust when applied in practical cases. Copyright © 2015 Elsevier B.V. All rights reserved.

The art of designing markets.

PubMed

Roth, Alvin E

2007-10-01

Traditionally, markets have been viewed as simply the confluence of supply and demand. But to function properly, they must be able to attract a sufficient number of buyers and sellers, induce participants to make their preferences clear, and overcome congestion by providing both enough time to make choices and a speedy means of registering them. Solutions to these challenges are the province of market design--a blend of game theory and experimental economics. Roth, a professor of both business and economics at Harvard, is a leading market designer. He and his colleagues have rescued failing markets by, for example, designing labor clearinghouses through which U.S. doctors get their first jobs and auctions through which the Federal Communications Commission sells licenses for parts of the radio broadcast spectrum. They have also created marketlike allocation procedures that involve neither prices nor an exchange of money; these include systems for assigning children to schools in Boston and New York and for facilitating exchanges of kidneys. Computers enable the design of "smart markets" that combine the inputs of users in complex ways: In kidney exchange, they run through every possible match of donors and recipients to arrange the greatest possible number of transplants. In the future, computers may make it possible to auction bundled goods, such as airport takeoff and landing slots. As online markets--like those for jobs and dating--proliferate, a growing understanding of markets in general will provide virtually limitless opportunities for market design.

77 FR 26021 - Center for Scientific Review; Notice of Closed Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-02

... . Name of Committee: Digestive, Kidney and Urological Systems Integrated Review Group; Clinical... 20892, (301) 806-0009, [email protected] . Name of Committee: Digestive, Kidney and Urological Systems Integrated Review Group; Pathobiology of Kidney Disease Study Section. Date: June 4, 2012. Time: 8...

15 CFR 700.1 - Purpose of this regulation.

Code of Federal Regulations, 2012 CFR

2012-01-01

... provides an operating system to support rapid industrial response to a national emergency. (e) To aid in... DEFENSE PRIORITIES AND ALLOCATIONS SYSTEM Purpose § 700.1 Purpose of this regulation. (a) Title I of the... Priorities and Allocations System (DPAS) regulation implements the priorities and allocations authority of...

15 CFR 700.1 - Purpose of this regulation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... provides an operating system to support rapid industrial response to a national emergency. (e) To aid in... DEFENSE PRIORITIES AND ALLOCATIONS SYSTEM Purpose § 700.1 Purpose of this regulation. (a) Title I of the... Priorities and Allocations System (DPAS) regulation implements the priorities and allocations authority of...

15 CFR 700.1 - Purpose of this regulation.

Code of Federal Regulations, 2013 CFR

2013-01-01

... provides an operating system to support rapid industrial response to a national emergency. (e) To aid in... DEFENSE PRIORITIES AND ALLOCATIONS SYSTEM Purpose § 700.1 Purpose of this regulation. (a) Title I of the... Priorities and Allocations System (DPAS) regulation implements the priorities and allocations authority of...

15 CFR 700.1 - Purpose of this regulation.

Code of Federal Regulations, 2014 CFR

2014-01-01

... provides an operating system to support rapid industrial response to a national emergency. (e) To aid in... DEFENSE PRIORITIES AND ALLOCATIONS SYSTEM Purpose § 700.1 Purpose of this regulation. (a) Title I of the... Priorities and Allocations System (DPAS) regulation implements the priorities and allocations authority of...

15 CFR 700.1 - Purpose of this regulation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... provides an operating system to support rapid industrial response to a national emergency. (e) To aid in... DEFENSE PRIORITIES AND ALLOCATIONS SYSTEM Purpose § 700.1 Purpose of this regulation. (a) Title I of the... Priorities and Allocations System (DPAS) regulation implements the priorities and allocations authority of...

78 FR 12294 - Proposed Information Collection; Comment Request; Defense Priorities and Allocations System

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-22

... Request; Defense Priorities and Allocations System AGENCY: Bureau of Industry and Security, Commerce...: Direct all written comments to Jennifer Jessup, Departmental Paperwork Clearance Officer, Department of... Priorities and Allocations System regulation (15 CFR part 700) must retain the records for at least 3 years...

75 FR 12173 - Proposed Information Collection; Comment Request; Defense Priorities and Allocations System

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-15

... Allocations System regulation (15 CFR part 700) must retain the records for at least 3 years. II. Method of... Request; Defense Priorities and Allocations System AGENCY: Bureau of Industry and Security, Commerce...: Direct all written comments to Diana Hynek, Departmental Paperwork Clearance Officer, Department of...

An Approach for Transmission Loss and Cost Allocation by Loss Allocation Index and Co-operative Game Theory

NASA Astrophysics Data System (ADS)

Khan, Baseem; Agnihotri, Ganga; Mishra, Anuprita S.

2016-03-01

In the present work authors proposed a novel method for transmission loss and cost allocation to users (generators and loads). In the developed methodology transmission losses are allocated to users based on their usage of the transmission line. After usage allocation, particular loss allocation indices (PLAI) are evaluated for loads and generators. Also Cooperative game theory approach is applied for comparison of results. The proposed method is simple and easy to implement on the practical power system. Sample 6 bus and IEEE 14 bus system is used for showing the effectiveness of proposed method.

10 CFR 217.54 - Elements of an allocation order.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Elements of an allocation order. 217.54 Section 217.54 Energy DEPARTMENT OF ENERGY OIL ENERGY PRIORITIES AND ALLOCATIONS SYSTEM Allocation Actions § 217.54 Elements of an allocation order. Each allocation order must include: (a) A detailed description of the...

10 CFR 217.54 - Elements of an allocation order.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false Elements of an allocation order. 217.54 Section 217.54 Energy DEPARTMENT OF ENERGY OIL ENERGY PRIORITIES AND ALLOCATIONS SYSTEM Allocation Actions § 217.54 Elements of an allocation order. Each allocation order must include: (a) A detailed description of the...

10 CFR 217.54 - Elements of an allocation order.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Elements of an allocation order. 217.54 Section 217.54 Energy DEPARTMENT OF ENERGY OIL ENERGY PRIORITIES AND ALLOCATIONS SYSTEM Allocation Actions § 217.54 Elements of an allocation order. Each allocation order must include: (a) A detailed description of the...

Spectrum Situational Awareness Capability: The Military Need and Potential Implementation Issues

DTIC Science & Technology

2006-10-01

Management Sensor Systems Frequency Management EW Systems Frequency Management Allied Battlespace Spectrum Management Restricted Frequency List Frequency...Management Restricted Frequency List Frequency Allocation Table Civil Frequency Use Data Inputs Negotiation and allocation process © Dstl 2006 26th...Management Restricted Frequency List Data Inputs Negotiation and allocation process Frequency Allocation Table SSA ES INT COP etc WWW Spectrum

Aging changes in the kidneys and bladder

MedlinePlus

... fluid from the body. The kidneys also help control the body's chemical balance. The kidneys are part of the urinary system, which also includes the ureters, bladder, and urethra. Muscle ... bladder control. AGING CHANGES AND THEIR EFFECTS ON THE KIDNEYS ...

Mistrust, misperceptions, and miscommunication: a qualitative study of preferences about kidney transplantation among African Americans.

PubMed

Wachterman, M W; McCarthy, E P; Marcantonio, E R; Ersek, M

2015-03-01

Kidney transplantation rates in the United States are lower among African Americans than among whites. Well-documented racial disparities in access to transplantation explain some, but not all, of these differences. Prior survey-based research suggests that African American dialysis patients are less likely than whites to desire transplantation, but little research has focused on an in-depth exploration of preferences about kidney transplantation among African Americans. Thus, the purposes of this study were to explore preferences and to compare patients' expectations about transplantation with actual status on the transplant list. We conducted semistructured interviews with 16 African Americans receiving chronic hemodialysis. We analyzed the interviews using the constant comparative method of qualitative analysis. We also reviewed the dialysis center's transplant list. Four dominant themes emerged: (1) varied desire for transplant; (2) concerns about donor source; (3) barriers to transplantation; and (4) lack of communication with nephrologists and the transplantation team. A thread of mistrust about equity in the transplantation process flowed through themes 2-4. In 7/16 cases, patients' understanding of their transplant listing status was discordant with their actual status. Our study suggests that many African Americans on hemodialysis are interested in kidney transplantation, but that interest is often tempered by concerns about transplantation, including misconceptions about the risks to recipients and donors. Mistrust about equity in the organ allocation process also contributed to ambivalence. The discordance between patients' perceptions of listing status and actual status suggests communication gaps between African American hemodialysis patients and physicians. Clinicians should avoid interpreting ambivalence about transplantation as lack of interest. Published by Elsevier Inc.

Does long-term creatine supplementation impair kidney function in resistance-trained individuals consuming a high-protein diet?

PubMed Central

2013-01-01

Background The aim of this study was to determine the effects of creatine supplementation on kidney function in resistance-trained individuals ingesting a high-protein diet. Methods A randomized, double-blind, placebo-controlled trial was performed. The participants were randomly allocated to receive either creatine (20 g/d for 5 d followed by 5 g/d throughout the trial) or placebo for 12 weeks. All of the participants were engaged in resistance training and consumed a high-protein diet (i.e., ≥ 1.2 g/Kg/d). Subjects were assessed at baseline (Pre) and after 12 weeks (Post). Glomerular filtration rate was measured by 51Cr-EDTA clearance. Additionally, blood samples and a 24-h urine collection were obtained for other kidney function assessments. Results No significant differences were observed for 51Cr-EDTA clearance throughout the trial (Creatine: Pre 101.42 ± 13.11, Post 108.78 ± 14.41 mL/min/1.73m2; Placebo: Pre 103.29 ± 17.64, Post 106.68 ± 16.05 mL/min/1.73m2; group x time interaction: F = 0.21, p = 0.64). Creatinine clearance, serum and urinary urea, electrolytes, proteinuria, and albuminuria remained virtually unchanged. Conclusions A 12-week creatine supplementation protocol did not affect kidney function in resistance-trained healthy individuals consuming a high-protein diet; thus reinforcing the safety of this dietary supplement. Trial registration ClinicalTrials.gov NCT01817673 PMID:23680457

Systems Toxicology of Chemically Induced Liver and Kidney Injuries: Histopathology-Associated Gene Co-Expression Modules

DTIC Science & Technology

2016-01-04

2016 (wileyonlinelibrary.com) DOI 10.1002/jat.3278Systems toxicology of chemically induced liver and kidney injuries: histopathology-associated gene...injuries that classify 11 liver and eight kidney histopathology endpoints based on dose-dependent activation of the identified modules. We showed that...well as determine whether the injury module activation was specific to the tissue of origin (liver and kidney ). The generated modules provide a link

Should We Formulate an Incentivized Model Facilitating Kidney Donation from Living Donors? A Focus on Turkey's Current System.

PubMed

Avci, Ercan

2018-04-23

Kidney transplantation is a lifesaving medical treatment. However, very high demand for kidneys with low kidney donation causes a black market that exploits patients' desperation and donors' vulnerability. The current kidney donation programs fail to produce promising results to avoid illegal and unethical kidney trafficking and commercialism. Even though the primary goal of kidney donation is to increase the number of deceased organ donations, in some countries, like Turkey, due to religious or cultural concerns, it is impossible to supply adequate deceased kidney donations. In this view, the aim of this paper is to examine kidney trafficking in the scope of Turkey's current organ donation system and propose a new model, named the Incentivized Kidney Donation Model (IKDM), to increase kidney donation from living donors. The model encompasses the following benefits offered to kidney donors; lifetime health insurance, exemptions from copayments/contribution shares, priority when receiving an organ, priority when finding a job, income tax exemptions for salaried employees, and free or discounted public utilities. This normative model has the potential to promote donors' altruistic acts as well as the solidarity and loyalty among members of a society without violating ethical values and internationally accepted principles. © 2018 John Wiley & Sons Ltd.

Mobile access to virtual randomization for investigator-initiated trials.

PubMed

Deserno, Thomas M; Keszei, András P

2017-08-01

Background/aims Randomization is indispensable in clinical trials in order to provide unbiased treatment allocation and a valid statistical inference. Improper handling of allocation lists can be avoided using central systems, for example, human-based services. However, central systems are unaffordable for investigator-initiated trials and might be inaccessible from some places, where study subjects need allocations. We propose mobile access to virtual randomization, where the randomization lists are non-existent and the appropriate allocation is computed on demand. Methods The core of the system architecture is an electronic data capture system or a clinical trial management system, which is extended by an R interface connecting the R server using the Java R Interface. Mobile devices communicate via the representational state transfer web services. Furthermore, a simple web-based setup allows configuring the appropriate statistics by non-statisticians. Our comprehensive R script supports simple randomization, restricted randomization using a random allocation rule, block randomization, and stratified randomization for un-blinded, single-blinded, and double-blinded trials. For each trial, the electronic data capture system or the clinical trial management system stores the randomization parameters and the subject assignments. Results Apps are provided for iOS and Android and subjects are randomized using smartphones. After logging onto the system, the user selects the trial and the subject, and the allocation number and treatment arm are displayed instantaneously and stored in the core system. So far, 156 subjects have been allocated from mobile devices serving five investigator-initiated trials. Conclusion Transforming pre-printed allocation lists into virtual ones ensures the correct conduct of trials and guarantees a strictly sequential processing in all trial sites. Covering 88% of all randomization models that are used in recent trials, virtual randomization becomes available for investigator-initiated trials and potentially for large multi-center trials.

Probabilistic resource allocation system with self-adaptive capability

NASA Technical Reports Server (NTRS)

Yufik, Yan M. (Inventor)

1996-01-01

A probabilistic resource allocation system is disclosed containing a low capacity computational module (Short Term Memory or STM) and a self-organizing associative network (Long Term Memory or LTM) where nodes represent elementary resources, terminal end nodes represent goals, and directed links represent the order of resource association in different allocation episodes. Goals and their priorities are indicated by the user, and allocation decisions are made in the STM, while candidate associations of resources are supplied by the LTM based on the association strength (reliability). Reliability values are automatically assigned to the network links based on the frequency and relative success of exercising those links in the previous allocation decisions. Accumulation of allocation history in the form of an associative network in the LTM reduces computational demands on subsequent allocations. For this purpose, the network automatically partitions itself into strongly associated high reliability packets, allowing fast approximate computation and display of allocation solutions satisfying the overall reliability and other user-imposed constraints. System performance improves in time due to modification of network parameters and partitioning criteria based on the performance feedback.

Probabilistic resource allocation system with self-adaptive capability

NASA Technical Reports Server (NTRS)

Yufik, Yan M. (Inventor)

1998-01-01

A probabilistic resource allocation system is disclosed containing a low capacity computational module (Short Term Memory or STM) and a self-organizing associative network (Long Term Memory or LTM) where nodes represent elementary resources, terminal end nodes represent goals, and weighted links represent the order of resource association in different allocation episodes. Goals and their priorities are indicated by the user, and allocation decisions are made in the STM, while candidate associations of resources are supplied by the LTM based on the association strength (reliability). Weights are automatically assigned to the network links based on the frequency and relative success of exercising those links in the previous allocation decisions. Accumulation of allocation history in the form of an associative network in the LTM reduces computational demands on subsequent allocations. For this purpose, the network automatically partitions itself into strongly associated high reliability packets, allowing fast approximate computation and display of allocation solutions satisfying the overall reliability and other user-imposed constraints. System performance improves in time due to modification of network parameters and partitioning criteria based on the performance feedback.

Evolving Reliability and Maintainability Allocations for NASA Ground Systems

NASA Technical Reports Server (NTRS)

Munoz, Gisela; Toon, T.; Toon, J.; Conner, A.; Adams, T.; Miranda, D.

2016-01-01

This paper describes the methodology and value of modifying allocations to reliability and maintainability requirements for the NASA Ground Systems Development and Operations (GSDO) programs subsystems. As systems progressed through their design life cycle and hardware data became available, it became necessary to reexamine the previously derived allocations. This iterative process provided an opportunity for the reliability engineering team to reevaluate allocations as systems moved beyond their conceptual and preliminary design phases. These new allocations are based on updated designs and maintainability characteristics of the components. It was found that trade-offs in reliability and maintainability were essential to ensuring the integrity of the reliability and maintainability analysis. This paper discusses the results of reliability and maintainability reallocations made for the GSDO subsystems as the program nears the end of its design phase.

Evolving Reliability and Maintainability Allocations for NASA Ground Systems

NASA Technical Reports Server (NTRS)

Munoz, Gisela; Toon, Troy; Toon, Jamie; Conner, Angelo C.; Adams, Timothy C.; Miranda, David J.

2016-01-01

This paper describes the methodology and value of modifying allocations to reliability and maintainability requirements for the NASA Ground Systems Development and Operations (GSDO) program’s subsystems. As systems progressed through their design life cycle and hardware data became available, it became necessary to reexamine the previously derived allocations. This iterative process provided an opportunity for the reliability engineering team to reevaluate allocations as systems moved beyond their conceptual and preliminary design phases. These new allocations are based on updated designs and maintainability characteristics of the components. It was found that trade-offs in reliability and maintainability were essential to ensuring the integrity of the reliability and maintainability analysis. This paper discusses the results of reliability and maintainability reallocations made for the GSDO subsystems as the program nears the end of its design phase.

Adaptive function allocation reduces performance costs of static automation

NASA Technical Reports Server (NTRS)

Parasuraman, Raja; Mouloua, Mustapha; Molloy, Robert; Hilburn, Brian

1993-01-01

Adaptive automation offers the option of flexible function allocation between the pilot and on-board computer systems. One of the important claims for the superiority of adaptive over static automation is that such systems do not suffer from some of the drawbacks associated with conventional function allocation. Several experiments designed to test this claim are reported in this article. The efficacy of adaptive function allocation was examined using a laboratory flight-simulation task involving multiple functions of tracking, fuel-management, and systems monitoring. The results show that monitoring inefficiency represents one of the performance costs of static automation. Adaptive function allocation can reduce the performance cost associated with long-term static automation.

Dynamic task allocation for a man-machine symbiotic system

NASA Technical Reports Server (NTRS)

Parker, L. E.; Pin, F. G.

1987-01-01

This report presents a methodological approach to the dynamic allocation of tasks in a man-machine symbiotic system in the context of dexterous manipulation and teleoperation. This report addresses a symbiotic system containing two symbiotic partners which work toward controlling a single manipulator arm for the execution of a series of sequential manipulation tasks. It is proposed that an automated task allocator use knowledge about the constraints/criteria of the problem, the available resources, the tasks to be performed, and the environment to dynamically allocate task recommendations for the man and the machine. The presentation of the methodology includes discussions concerning the interaction of the knowledge areas, the flow of control, the necessary communication links, and the replanning of the task allocation. Examples of task allocation are presented to illustrate the results of this methodolgy.

Allocation Usage Tracking and Management | High-Performance Computing |

Science.gov Websites

NREL's high-performance computing (HPC) systems, learn how to track and manage your allocations. The alloc_tracker script (/usr/local/bin/alloc_tracker) may be used to see what allocations you have access to, how much of the allocation has been used, how much remains and how many node hours will be forfeited at the

The role of the immune system in kidney disease.

PubMed

Tecklenborg, J; Clayton, D; Siebert, S; Coley, S M

2018-05-01

The immune system and the kidneys are closely linked. In health the kidneys contribute to immune homeostasis, while components of the immune system mediate many acute forms of renal disease and play a central role in progression of chronic kidney disease. A dysregulated immune system can have either direct or indirect renal effects. Direct immune-mediated kidney diseases are usually a consequence of autoantibodies directed against a constituent renal antigen, such as collagen IV in anti-glomerular basement membrane disease. Indirect immune-mediated renal disease often follows systemic autoimmunity with immune complex formation, but can also be due to uncontrolled activation of the complement pathways. Although the range of mechanisms of immune dysregulation leading to renal disease is broad, the pathways leading to injury are similar. Loss of immune homeostasis in renal disease results in perpetual immune cell recruitment and worsening damage to the kidney. Uncoordinated attempts at tissue repair, after immune-mediated disease or non-immune mediated injury, result in fibrosis of structures important for renal function, leading eventually to kidney failure. As renal disease often manifests clinically only when substantial damage has already occurred, new diagnostic methods and indeed treatments must be identified to inhibit further progression and promote appropriate tissue repair. Studying cases in which immune homeostasis is re-established may reveal new treatment possibilities. © 2018 British Society for Immunology.

Resource Allocation and Public Policy in Alberta's Postsecondary System.

ERIC Educational Resources Information Center

Barneston, Bob; Boberg, Alice

2000-01-01

Resource allocation in Alberta's postsecondary system has changed substantially since 1994, designed to reapportion financial responsibility for higher education, increase vocational outcomes of postsecondary education, and increase transfer of knowledge and technology to the private sector. This paper outlines how resource allocation has been…

Studying Kidney Disease Using Tissue and Genome Engineering in Human Pluripotent Stem Cells.

PubMed

Garreta, Elena; González, Federico; Montserrat, Núria

2018-01-01

Kidney morphogenesis and patterning have been extensively studied in animal models such as the mouse and zebrafish. These seminal studies have been key to define the molecular mechanisms underlying this complex multistep process. Based on this knowledge, the last 3 years have witnessed the development of a cohort of protocols allowing efficient differentiation of human pluripotent stem cells (hPSCs) towards defined kidney progenitor populations using two-dimensional (2D) culture systems or through generating organoids. Kidney organoids are three-dimensional (3D) kidney-like tissues, which are able to partially recapitulate kidney structure and function in vitro. The current possibility to combine state-of-the art tissue engineering with clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated systems 9 (Cas9)-mediated genome engineering provides an unprecedented opportunity for studying kidney disease with hPSCs. Recently, hPSCs with genetic mutations introduced through CRISPR/Cas9-mediated genome engineering have shown to produce kidney organoids able to recapitulate phenotypes of polycystic kidney disease and glomerulopathies. This mini review provides an overview of the most recent advances in differentiation of hPSCs into kidney lineages, and the latest implementation of the CRISPR/Cas9 technology in the organoid setting, as promising platforms to study human kidney development and disease. © 2017 S. Karger AG, Basel.

Planning attitudes, lay philosophies, and water allocation: A preliminary analysis and research agenda

NASA Astrophysics Data System (ADS)

Syme, Geoffrey J.; Nancarrow, Blair E.

Despite the important societal consequences of water policy, community attitudes toward planning, ethics, and equity for allocation of water have received little research attention. This preliminary research was conducted to assess the range and structure of planning attitudes and equity and ethical considerations which might be relevant to the general public's evaluation of water allocation systems. The relationship of these to priorities for water allocation were also examined. The results showed a complex structure for planning attitudes. There were also generalized but clearly defined community approaches to water allocation. A number of significant relationships between planning attitudes and philosophies of allocation were shown. Planning attitudes also related to priorities for water allocation. In practical terms the research provides some preliminary, ethically based evaluative criteria which could be applied to allocation decision-making systems. Theoretical research possibilities are also outlined.

Serum Phosphorus and Risk of Cardiovascular Disease, All-Cause Mortality, or Graft Failure in Kidney Transplant Recipients: An Ancillary Study of the FAVORIT Trial Cohort

PubMed Central

Merhi, Basma; Shireman, Theresa; Carpenter, Myra A.; Kusek, John W.; Jacques, Paul; Pfeffer, Marc; Rao, Madhumathi; Foster, Meredith C.; Kim, S. Joseph; Pesavento, Todd E.; Smith, Stephen R.; Kew, Clifton E.; House, Andrew A.; Gohh, Reginald; Weiner, Daniel E.; Levey, Andrew S.; Ix, Joachim H.; Bostom, Andrew

2017-01-01

Background Mild hyperphosphatemia is a putative risk factor for cardiovascular disease [CVD], loss of kidney function, and mortality. Very limited data are available from sizable multicenter kidney transplant recipient (KTR) cohorts assessing the potential relationships between serum phosphorus levels and the development of CVD outcomes, transplant failure, or all-cause mortality. Study Design Cohort study. Setting & Participants The Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) Trial, a large, multicenter, multiethnic, controlled clinical trial that provided definitive evidence that high-dose vitamin B–based lowering of plasma homocysteine levels did not reduce CVD events, transplant failure, or total mortality in stable KTRs. Predictor Serum phosphorus levels were determined in 3,138 FAVORIT trial participants at randomization. Results During a median follow-up of 4.0 years, the cohort had 436 CVD events, 238 transplant failures, and 348 deaths. Proportional hazards modeling revealed that each 1-mg/dL higher serum phosphorus level was not associated with a significant increase in CVD risk (HR, 1.06; 95% CI, 0.92–1.22), but increased transplant failure (HR, 1.36; 95% CI, 1.15–1.62) and total mortality risk associations (HR, 1.21; 95% CI, 1.04–1.40) when adjusted for treatment allocation, traditional CVD risk factors, kidney measures, type of kidney transplant, transplant vintage, and use of calcineurin inhibitors, steroids, or lipid-lowering drugs. These associations were strengthened in models without kidney measures: CVD (HR, 1.14; 95% CI, 1.00–1.31), transplant failure (HR, 1.72; 95% CI, 1.46–2.01), and mortality (HR, 1.34; 95% CI, 1.15–1.54). Limitations We lacked data for concentrations of parathyroid hormone, fibroblast growth factor 23, or vitamin D metabolites. Conclusions Serum phosphorus level is marginally associated with CVD and more strongly associated with transplant failure and total mortality in long-term KTRs. A randomized controlled clinical trial in KTRs that assesses the potential impact of phosphorus-lowering therapy on these hard outcomes may be warranted. PMID:28579423

Measurement of bio-impedance with a smart needle to confirm percutaneous kidney access.

PubMed

Hernandez, D J; Sinkov, V A; Roberts, W W; Allaf, M E; Patriciu, A; Jarrett, T W; Kavoussi, L R; Stoianovici, D

2001-10-01

The traditional method of percutaneous renal access requires freehand needle placement guided by C-arm fluoroscopy, ultrasonography, or computerized tomography. This approach provides limited objective means for verifying successful access. We developed an impedance based percutaneous Smart Needle system and successfully used it to confirm collecting system access in ex vivo porcine kidneys. The Smart Needle consists of a modified 18 gauge percutaneous access needle with the inner stylet electrically insulated from the outer sheath. Impedance is measured between the exposed stylet tip and sheath using Model 4275 LCR meter (Hewlett-Packard, Sunnyvale, California). An ex vivo porcine kidney was distended by continuous gravity infusion of 100 cm. water saline from a catheter passed through the parenchyma into the collecting system. The Smart Needle was gradually inserted into the kidney to measure depth precisely using a robotic needle placement system, while impedance was measured continuously. The Smart Needle was inserted 4 times in each of 4 kidneys. When the needle penetrated the distended collecting system in 11 of 16 attempts, a characteristic sharp drop in resistivity was noted from 1.9 to 1.1 ohm m. Entry into the collecting system was confirmed by removing the stylet and observing fluid flow from the sheath. This characteristic impedance change was observed only at successful entry into the collecting system. A characteristic sharp drop in impedance signifies successful entry into the collecting system. The Smart Needle system may prove useful for percutaneous kidney access.

Effects of pituitary adenylate cyclase activating polypeptide in the urinary system, with special emphasis on its protective effects in the kidney.

PubMed

Reglodi, Dora; Kiss, Peter; Horvath, Gabriella; Lubics, Andrea; Laszlo, Eszter; Tamas, Andrea; Racz, Boglarka; Szakaly, Peter

2012-04-01

Pituitary adenylate cyclase activating polypeptide (PACAP) is a widespread neuropeptide with diverse effects in the nervous system and peripheral organs. One of the most well-studied effects of PACAP is its cytoprotective action, against different harmful stimuli in a wide variety of cells and tissues. PACAP occurs in the urinary system, from the kidney to the lower urinary tract. The present review focuses on the nephroprotective effects of PACAP and summarizes data obtained regarding the protective effects of PACAP in different models of kidney pathologies. In vitro data show that PACAP protects tubular cells against oxidative stress, myeloma light chain, cisplatin, cyclosporine-A and hypoxia. In vivo data provide evidence for its protective effects in ischemia/reperfusion, cisplatin, cyclosporine-A, myeloma kidney injury, diabetic nephropathy and gentamicin-induced kidney damage. Results accumulated on the renoprotective effects of PACAP suggest that PACAP is an emerging candidate for treatment of human kidney pathologies. Copyright © 2011 Elsevier Ltd. All rights reserved.

48 CFR 9904.413 - Adjustment and allocation of pension cost.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Adjustment and allocation of pension cost. 9904.413 Section 9904.413 Federal Acquisition Regulations System COST ACCOUNTING... AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.413 Adjustment and allocation of pension...

Detection of cytomegalovirus (CMV) antigens in kidney biopsies and transplant nephrectomies as a marker for renal graft dysfunction.

PubMed

Gerstenkorn, C; Robertson, H; Mohamed, M A; O'Donnell, M; Ali, S; Talbot, D

2000-11-01

Chronic rejection accounts for the greatest loss of renal allografts. HLA mismatching has been minimised by organ allocation and new immunosuppressive drugs have been employed, but the average cadaveric graft survival still does not exceed 12 years. Though the aetiology is multifactorial, one contributory factor for this condition is cytomegalovirus (CMV). Detection of CMV in kidney biopsies and sera can diagnose and monitor this inflammatory event and define its role in chronic nephropathy. Twenty five biopsies taken at the time of transplantation, 10 biopsies for graft dysfunction and tissue blocks from 20 explanted kidney grafts were collected and investigated for CMV antigens by immunohistochemistry. Tissue samples were snap frozen and cryostat sections were incubated with monoclonal antibodies for CMV antigens followed by immunoperoxidase staining. In 12 out of 20 transplant nephrectomies CMV antigens were found. Only two of these patients had clinical CMV disease. Time 0 biopsies from CMV seronegative donors (n = 11) and CMV seropositive donors (n = 14) were negative for CMV antigens. The prevalence of CMV antigens in grafts lost due to chronic rejection was 60%. These antigens were not found within the time 0 biopsies, but were detected in 30% of biopsies taken at the time of clinical graft dysfunction. CMV appears to contribute to chronic rejection even without clinical disease.

FOR Allocation to Distribution Systems based on Credible Improvement Potential (CIP)

NASA Astrophysics Data System (ADS)

Tiwary, Aditya; Arya, L. D.; Arya, Rajesh; Choube, S. C.

2017-02-01

This paper describes an algorithm for forced outage rate (FOR) allocation to each section of an electrical distribution system subject to satisfaction of reliability constraints at each load point. These constraints include threshold values of basic reliability indices, for example, failure rate, interruption duration and interruption duration per year at load points. Component improvement potential measure has been used for FOR allocation. Component with greatest magnitude of credible improvement potential (CIP) measure is selected for improving reliability performance. The approach adopted is a monovariable method where one component is selected for FOR allocation and in the next iteration another component is selected for FOR allocation based on the magnitude of CIP. The developed algorithm is implemented on sample radial distribution system.

Standard versus accelerated initiation of renal replacement therapy in acute kidney injury (STARRT-AKI): study protocol for a randomized controlled trial.

PubMed

Smith, Orla M; Wald, Ron; Adhikari, Neill K J; Pope, Karen; Weir, Matthew A; Bagshaw, Sean M

2013-10-05

Acute kidney injury is a common and devastating complication of critical illness, for which renal replacement therapy is frequently needed to manage severe cases. While a recent systematic review suggested that "earlier" initiation of renal replacement therapy improves survival, completed trials are limited due to small size, single-centre status, and use of variable definitions to define "early" renal replacement therapy initiation. This is an open-label pilot randomized controlled trial. One hundred critically ill patients with severe acute kidney injury will be randomly allocated 1:1 to receive "accelerated" initiation of renal replacement therapy or "standard" initiation at 12 centers across Canada. In the accelerated arm, participants will have a venous catheter placed and renal replacement therapy will be initiated within 12 hours of fulfilling eligibility. In the standard initiation arm, participants will be monitored over 7 days to identify indications for renal replacement therapy. For participants in the standard arm with persistent acute kidney injury, defined as a serum creatinine not declining >50% from the value at the time of eligibility, the initiation of RRT will be discouraged unless one or more of the following criteria are fulfilled: serum potassium ≥6.0 mmol/L; serum bicarbonate ≤10 mmol/L; severe respiratory failure (PaO₂/FiO₂<200) or persisting acute kidney injury for ≥72 hours after fulfilling eligibility. The inclusion criteria are designed to identify a population of critically ill adults with severe acute kidney injury who are likely to need renal replacement therapy during their hospitalization, but not immediately. The primary outcome is protocol adherence (>90%). Secondary outcomes include measures of feasibility (proportion of eligible patients enrolled in the trial, proportion of enrolled patients followed to 90 days for assessment of vital status and the need for renal replacement therapy) and safety (occurrence of adverse events). The optimal timing of renal replacement therapy initiation in patients with severe acute kidney injury remains uncertain, representing an important knowledge gap and a priority for high-quality research. This pilot trial is necessary to establish protocol feasibility, confirm the safety of participants and obtain estimated events rates for design of a large definitive trial. NCT01557361.

Model systems for the study of kidney development: use of the pronephros in the analysis of organ induction and patterning.

PubMed

Vize, P D; Seufert, D W; Carroll, T J; Wallingford, J B

1997-08-15

Most vertebrate organs, once formed, continue to perform the function for which they were generated until the death of the organism. The kidney is a notable exception to this rule. Vertebrates, even those that do not undergo metamorphosis, utilize a progression of more complex kidneys as they grow and develop. This is presumably due to the changing conditions to which the organism must respond to retain what Homer Smith referred to as our physiological freedom. To quote, "Recognizing that we have the kind of blood we have because we have the kind of kidneys we have, we must acknowledge that our kidneys constitute the major foundation of our physiological freedom. Only because they work the way they do has it become possible for us to have bones, muscles, glands, and brains. Superficially, it might be said that the function of the kidneys is to make urine; but in a more considered view one can say that the kidneys make the stuff of philosophy itself" ("From Fish to Philosopher," Little, Brown and Co., Boston, 1953). Different kidneys are used to make the stuff of philosophy at different stages of development depending on the age and needs of the organism, rather than the usual approach of simply making embryonic organs larger as the animal grows. Although evolution has provided the higher vertebrates with complex adult kidneys, they continue to utilize simple kidneys in embryogenesis. In lower vertebrates with simple adult kidneys, even more simple versions are used during early developmental stages. In this review the anatomy, development, and gene expression patterns of the embryonic kidney, the pronephros, will be described and compared to the more complex kidney forms. Despite some differences in anatomy, similar developmental pathways seem to be responsible for the induction and the response to induction in both evanescent and permanent kidney forms. Gene expression patterns can, therefore, be added to the morphological and functional data indicating that all forms of the kidney are closely related structures. Given the similarities between the development of simple and complex kidneys, the embryonic kidneys may be an ideal model system in which to investigate the genesis of multicomponent organ systems.

48 CFR 9904.403 - Allocation of home office expenses to segments.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 7 2012-10-01 2012-10-01 false Allocation of home office expenses to segments. 9904.403 Section 9904.403 Federal Acquisition Regulations System COST ACCOUNTING... AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.403 Allocation of home office expenses to...

Cost Allocation Issues in Interlibrary Systems.

ERIC Educational Resources Information Center

Alexander, Ernest R.

1985-01-01

In comparing methods of allocating service transaction costs among member libraries of interlibrary systems, questions of how costs are to be estimated, and what cost elements are to be included are critical. Different approaches of estimation yield varying results. Actual distribution of units accounts for greatest variance in allocations. (CDD)

Budgeting by Objectives--How Goals and Objectives, Operational Activities, and Resource Allocation Are Integrated in a Planning System. AIR 1984 Annual Forum Paper.

ERIC Educational Resources Information Center

Capoor, Madan

The Objective-Based Assessment, Planning, and Resource Allocation System (OAPRAS) that was developed and implemented at Middlesex County College is described. The integrated self-assessment planning and budgeting system was developed in 1981. The central purpose of OAPRAS was to link resource allocation decisions to the prioritized objectives that…

The need for kidney transplantation in low- and middle-income countries in 2012: an epidemiological perspective.

PubMed

Muralidharan, Aditya; White, Sarah

2015-03-01

Epidemiological and demographic transitions are shifting the burden of modifiable risk factors for chronic and end-stage kidney disease to low- and middle-income countries (LMIC). This shifting burden of disease--combined with economic transitions and health system reforms--has led to the rapid growth of dialysis populations in LMIC including Malaysia, Tunisia, Turkey, Chile, Mexico, and Uruguay. Yet, compared to 1.5 million on dialysis in LMIC, only approximately 33,000 kidney transplants were performed in 2012. Reasons include health system factors (personnel, infrastructure, system coordination, and financing) and cultural factors (public and professional attitudes and the legal environment). The size of the dialysis populations, however, is generally a poor indicator of the potential need for kidney transplantation in LMIC. Population needs for kidney transplantation should instead be assessed based on the epidemiology of the actual underlying burden of disease (both treated and untreated), and the costs and benefits of treatment as well as prevention strategies relative to existing service provision. Here, we review current data on the global burden of end-stage kidney disease and the distribution of major risk factors, and compare this to access to kidney transplantation in 2012.

Optimal Resource Allocation under Fair QoS in Multi-tier Server Systems

NASA Astrophysics Data System (ADS)

Akai, Hirokazu; Ushio, Toshimitsu; Hayashi, Naoki

Recent development of network technology realizes multi-tier server systems, where several tiers perform functionally different processing requested by clients. It is an important issue to allocate resources of the systems to clients dynamically based on their current requests. On the other hand, Q-RAM has been proposed for resource allocation in real-time systems. In the server systems, it is important that execution results of all applications requested by clients are the same QoS(quality of service) level. In this paper, we extend Q-RAM to multi-tier server systems and propose a method for optimal resource allocation with fairness of the QoS levels of clients’ requests. We also consider an assignment problem of physical machines to be sleep in each tier sothat the energy consumption is minimized.

An Optimization Framework for Dynamic, Distributed Real-Time Systems

NASA Technical Reports Server (NTRS)

Eckert, Klaus; Juedes, David; Welch, Lonnie; Chelberg, David; Bruggerman, Carl; Drews, Frank; Fleeman, David; Parrott, David; Pfarr, Barbara

2003-01-01

Abstract. This paper presents a model that is useful for developing resource allocation algorithms for distributed real-time systems .that operate in dynamic environments. Interesting aspects of the model include dynamic environments, utility and service levels, which provide a means for graceful degradation in resource-constrained situations and support optimization of the allocation of resources. The paper also provides an allocation algorithm that illustrates how to use the model for producing feasible, optimal resource allocations.

Task allocation model for minimization of completion time in distributed computer systems

NASA Astrophysics Data System (ADS)

Wang, Jai-Ping; Steidley, Carl W.

1993-08-01

A task in a distributed computing system consists of a set of related modules. Each of the modules will execute on one of the processors of the system and communicate with some other modules. In addition, precedence relationships may exist among the modules. Task allocation is an essential activity in distributed-software design. This activity is of importance to all phases of the development of a distributed system. This paper establishes task completion-time models and task allocation models for minimizing task completion time. Current work in this area is either at the experimental level or without the consideration of precedence relationships among modules. The development of mathematical models for the computation of task completion time and task allocation will benefit many real-time computer applications such as radar systems, navigation systems, industrial process control systems, image processing systems, and artificial intelligence oriented systems.

IDENTIFICATION OF DIFFERENTIALLY EXPRESSED GENES IN THE KIDNEYS OF GROWTH HORMONE TRANSGENIC MICE

PubMed Central

Coschigano, K.T.; Wetzel, A.N.; Obichere, N.; Sharma, A.; Lee, S.; Rasch, R.; Guigneaux, M.M.; Flyvbjerg, A.; Wood, T.G.; Kopchick, J.J.

2010-01-01

Objective Bovine growth hormone (bGH) transgenic mice develop severe kidney damage. This damage may be due, at least in part, to changes in gene expression. Identification of genes with altered expression in the bGH kidney may identify mechanisms leading to damage in this system that may also be relevant to other models of kidney damage. Design cDNA subtraction libraries, northern blot analyses, microarray analyses and real-time reverse transcription polymerase chain reaction (RT/PCR) assays were used to identify and verify specific genes exhibiting differential RNA expression between kidneys of bGH mice and their non-transgenic (NT) littermates. Results Immunoglobulins were the vast majority of genes identified by the cDNA subtractions and the microarray analyses as being up-regulated in bGH. Several glycoprotein genes and inflammation-related genes also showed increased RNA expression in the bGH kidney. In contrast, only a few genes were identified as being significantly down-regulated in the bGH kidney. The most notable decrease in RNA expression was for the gene encoding kidney androgen-regulated protein. Conclusions A number of genes were identified as being differentially expressed in the bGH kidney. Inclusion of two groups, immunoglobulins and inflammation-related genes, suggests a role of the immune system in bGH kidney damage. PMID:20655258

Antioxidant and anti-inflammatory potential of pomegranate rind extract to ameliorate cisplatin-induced acute kidney injury.

PubMed

Karwasra, Ritu; Kalra, Prerna; Gupta, Yogendra Kumar; Saini, Deepika; Kumar, Ajay; Singh, Surender

2016-07-13

Cisplatin is a chemotherapeutic agent, but the therapeutic utility is limited due to its dose dependent nephrotoxicity. The aim of the present study was to evaluate the nephroprotective effect of pomegranate in cisplatin-induced acute kidney injury. Wistar rats were allocated into six groups as follows: the normal control, cisplatin-induced, pomegranate rind extract treatment (50, 100 and 200 mg kg(-1)) and pomegranate rind extract per se group. All the experimental test drugs/vehicle were administered orally for a period of ten days. Intraperitoneal injection of cisplatin (8 mg kg(-1)) was administered on day 7 to all the groups except the normal control and pomegranate per se group. On day 10, cisplatin resulted in significant nephrotoxicity in Wistar rats with a drastic elevation of serum creatinine and BUN, a decline in the concentrations of GSH, MDA and superoxide dismutase (SOD), and an elevation in the TNF-α level in renal tissues. Pathological changes in renal tissues were examined by histopathology and dysfunction in mitochondria and proximal tubule cells was detected by transmission electron microscopy. The rate of apoptosis and the expression of caspase-3, Il-1β and IL-6 in rat renal tissues were detected by immunohistochemistry. The administration of pomegranate at a dose of 200 mg per kg body weight significantly (p < 0.001) ameliorates increased serum creatinine and BUN. In parallel to this, pomegranate also exhibits anti-apoptotic activity through the reduction of active caspase-3 expression in kidneys. Additionally, in-silico studies also confirmed a renoprotective effect of pomegranate. The above findings suggest that pomegranate can be used as a dietary supplement in the treatment of cisplatin-induced kidney injury by reducing apoptosis, oxidative stress and inflammation.

21 CFR 866.5320 - Properdin factor B immuno-logical test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... factor B aids in the diagnosis of several kidney diseases, e.g., chronic glomerulonephritis (inflammation of the glomeruli of the kidney), lupus nephritis (kidney disease associated with a multisystem...

American Kidney Fund

MedlinePlus

... Carolyn Wilson Scholarship Program Grants Managements System (GMS) Login Education & Research Patient webinars Become a kidney health ... Blog Newsroom Contact Us HelpLine En Español GMS Login Give Monthly Give In Honor Donate Kidney Disease ...

Tests for Kidney Health

MedlinePlus

... Carolyn Wilson Scholarship Program Grants Managements System (GMS) Login Education & Research Webinars Become a Kidney Health Coach ... Blog Newsroom Contact Us HelpLine En Español GMS Login Give Monthly Give In Honor Donate Kidney Disease ...

Influence of low-level laser radiation on kidney functions

NASA Astrophysics Data System (ADS)

Koultchavenia, Ekaterina V.

1998-12-01

Most of all renal diseases are accompanied by lowering of kidney functions. That makes the quality of the treatment worse. On an example 69 patients receiving Low-Level Laser Therapy (LLLT), the influence of the laser radiation on a contracting system of blood, on current of an active and inactive tubercular inflammation and on partial functions of kidneys were investigated. Is established, that LLLT does not render influence to a contracting system; promotes stopping of unspecific and moderate peaking of a specific inflammation of kidneys. Is proved, that after a rate of laserotherapy the improving of a blood micricirculation in kidney occurs in 57.9% of patients; a secretion - in 63.1% of the patients; a stimulation of urodynamic is fixed in 79% of cases. Magnification of diuresis, improving filtration and concentration functions of kidneys also is marked.

S4HARA: System for HIV/AIDS resource allocation.

PubMed

Lasry, Arielle; Carter, Michael W; Zaric, Gregory S

2008-03-26

HIV/AIDS resource allocation decisions are influenced by political, social, ethical and other factors that are difficult to quantify. Consequently, quantitative models of HIV/AIDS resource allocation have had limited impact on actual spending decisions. We propose a decision-support System for HIV/AIDS Resource Allocation (S4HARA) that takes into consideration both principles of efficient resource allocation and the role of non-quantifiable influences on the decision-making process for resource allocation. S4HARA is a four-step spreadsheet-based model. The first step serves to identify the factors currently influencing HIV/AIDS allocation decisions. The second step consists of prioritizing HIV/AIDS interventions. The third step involves allocating the budget to the HIV/AIDS interventions using a rational approach. Decision-makers can select from several rational models of resource allocation depending on availability of data and level of complexity. The last step combines the results of the first and third steps to highlight the influencing factors that act as barriers or facilitators to the results suggested by the rational resource allocation approach. Actionable recommendations are then made to improve the allocation. We illustrate S4HARA in the context of a primary healthcare clinic in South Africa. The clinic offers six types of HIV/AIDS interventions and spends US$750,000 annually on these programs. Current allocation decisions are influenced by donors, NGOs and the government as well as by ethical and religious factors. Without additional funding, an optimal allocation of the total budget suggests that the portion allotted to condom distribution be increased from 1% to 15% and the portion allotted to prevention and treatment of opportunistic infections be increased from 43% to 71%, while allocation to other interventions should decrease. Condom uptake at the clinic should be increased by changing the condom distribution policy from a pull system to a push system. NGOs and donors promoting antiretroviral programs at the clinic should be sensitized to the results of the model and urged to invest in wellness programs aimed at the prevention and treatment of opportunistic infections. S4HARA differentiates itself from other decision support tools by providing rational HIV/AIDS resource allocation capabilities as well as consideration of the realities facing authorities in their decision-making process.

Comparison of the Protective Effects of Melatonin and Silymarin Against Gentamicin-Induced Nephrotoxicity in Rats.

PubMed

Ghaznavi, Habib; Mehrzadi, Saeed; Dormanesh, Banafshe; Tabatabaei, Seyyed Mohammad Taghi Hosseini; Vahedi, Habib; Hosseinzadeh, Azam; Pazoki-Toroudi, HamidReza; Rashidian, Amir

2016-10-01

This study compared the possible protective effects of silymarin and melatonin against gentamicin (GEN)-induced nephrotoxicity in rats. Rats were allocated to 6 groups: Group I, control group; Groups II and III, administered with silymarin or melatonin; Group IV, injected with GEN; and Groups V and VI, administered with silymarin or melatonin, and then injected with GEN. Compared with the rats in the control group, all rats injected with GEN significantly presented elevated levels of serum creatinine and urea that was accompanied by an increase in relative kidney weight, increase in renal reactive oxygen species (ROS) and malondialdehyde (MDA) levels, and reduction in renal glutathione (GSH) level and superoxide dismutase (SOD) activity. Silymarin and melatonin pretreatment significantly lowered the elevated serum urea and creatinine concentration, kidney weight, and renal ROS and MDA levels. In addition, silymarin and melatonin significantly enhanced renal GSH level and SOD activity. This study indicates that silymarin and melatonin can attenuate renal injury in rats treated with GEN possibly by reducing the ROS level. © The Author(s) 2015.

Tamm-Horsfall Protein Regulates Granulopoiesis and Systemic Neutrophil Homeostasis

PubMed Central

Micanovic, Radmila; Chitteti, Brahmananda R.; Dagher, Pierre C.; Srour, Edward F.; Khan, Shehnaz; Hato, Takashi; Lyle, Allison; Tong, Yan; Wu, Xue-Ru

2015-01-01

Tamm-Horsfall protein (THP) is a glycoprotein uniquely expressed in the kidney. We recently showed an important role for THP in mediating tubular cross-talk in the outer medulla and in suppressing neutrophil infiltration after kidney injury. However, it remains unclear whether THP has a broader role in neutrophil homeostasis. In this study, we show that THP deficiency in mice increases the number of neutrophils, not only in the kidney but also in the circulation and in the liver, through enhanced granulopoiesis in the bone marrow. Using multiplex ELISA, we identified IL-17 as a key granulopoietic cytokine specifically upregulated in the kidneys but not in the liver of THP−/− mice. Indeed, neutralization of IL-17 in THP−/− mice completely reversed the systemic neutrophilia. Furthermore, IL-23 was also elevated in THP−/− kidneys. We performed real-time PCR on laser microdissected tubular segments and FACS-sorted renal immune cells and identified the S3 proximal segments, but not renal macrophages, as a major source of increased IL-23 synthesis. In conclusion, we show that THP deficiency stimulates proximal epithelial activation of the IL-23/IL-17 axis and systemic neutrophilia. Our findings provide evidence that the kidney epithelium in the outer medulla can regulate granulopoiesis. When this novel function is added to its known role in erythropoiesis, the kidney emerges as an important regulator of the hematopoietic system. PMID:25556169

Robotics applied in laparoscopic kidney surgery: the Yonsei University experience of 127 cases.

PubMed

Lorenzo, Enrique Ian S; Jeong, Wooju; Oh, Cheol Kyu; Chung, Byung Ha; Choi, Young Deuk; Rha, Koon Ho

2011-01-01

We report our experience on 127 kidney surgeries with the da Vinci surgical system and show the feasibility of a robotics application in a variety of kidney surgeries by both a laparoscopically-trained and a laparoscopically-naïve surgeon. Clinical data of patients who underwent kidney surgery with the da Vinci surgical system from September 2006 to April 2009 were reviewed. Data acquired from medical records included patient demographics, operative time, estimated blood loss (EBL), incidence of intraoperative complication, duration of hospital stay, blood transfusion rate, oncological outcomes, and follow-up results. One-hundred twenty-seven kidney surgeries have been conducted with the da Vinci surgical system at our institution. Three urologists--1 with formal endourology training, 1 with laparoscopic experience, and 1 laparoscopically naïve--have used it for a variety of procedures involving the kidney. The cases include 65 partial nephrectomies (RPN), 38 radical nephrectomies (RRN), and 24 nephroureterectomies with bladder cuff (RNU). Results on operative time, EBL, incidence of intraoperative injury, duration of hospital stay, and blood transfusion rate are comparable with contemporary studies. Robotics application in kidney surgery is a viable option for various procedures. Our experience shows it can be safely and effectively conducted by both laparoscopically-trained and laparoscopically-naïve surgeons once they are accustomed to the robotics system. Copyright © 2011 Elsevier Inc. All rights reserved.

Use of Readily Accessible Inflammatory Markers to Predict Diabetic Kidney Disease.

PubMed

Winter, Lauren; Wong, Lydia A; Jerums, George; Seah, Jas-Mine; Clarke, Michele; Tan, Sih Min; Coughlan, Melinda T; MacIsaac, Richard J; Ekinci, Elif I

2018-01-01

Diabetic kidney disease is a common complication of type 1 and type 2 diabetes and is the primary cause of end-stage renal disease in developed countries. Early detection of diabetic kidney disease will facilitate early intervention aimed at reducing the rate of progression to end-stage renal disease. Diabetic kidney disease has been traditionally classified based on the presence of albuminuria. More recently estimated glomerular filtration rate has also been incorporated into the staging of diabetic kidney disease. While albuminuric diabetic kidney disease is well described, the phenotype of non-albuminuric diabetic kidney disease is now widely accepted. An association between markers of inflammation and diabetic kidney disease has previously been demonstrated. Effector molecules of the innate immune system including C-reactive protein, interleukin-6, and tumor necrosis factor-α are increased in patients with diabetic kidney disease. Furthermore, renal infiltration of neutrophils, macrophages, and lymphocytes are observed in renal biopsies of patients with diabetic kidney disease. Similarly high serum neutrophil and low serum lymphocyte counts have been shown to be associated with diabetic kidney disease. The neutrophil-lymphocyte ratio is considered a robust measure of systemic inflammation and is associated with the presence of inflammatory conditions including the metabolic syndrome and insulin resistance. Cross-sectional studies have demonstrated a link between high levels of the above inflammatory biomarkers and diabetic kidney disease. Further longitudinal studies will be required to determine if these readily available inflammatory biomarkers can accurately predict the presence and prognosis of diabetic kidney disease, above and beyond albuminuria, and estimated glomerular filtration rate.

Assessing the likely harms to kidney vendors in regulated organ markets.

PubMed

Koplin, Julian

2014-01-01

Advocates of paid living kidney donation frequently argue that kidney sellers would benefit from paid donation under a properly regulated kidney market. The poor outcomes experienced by participants in existing markets are often entirely attributed to harmful black-market practices. This article reviews the medical and anthropological literature on the physical, psychological, social, and financial harms experienced by vendors under Iran's regulated system of donor compensation and black markets throughout the world and argues that this body of research not only documents significant harms to vendors, but also provides reasons to believe that such harms would persist under a regulated system. This does not settle the question of whether or not a regulated market should be introduced, but it does strengthen the case against markets in kidneys while suggesting that those advocating such a system cannot appeal to the purported benefits to vendors to support their case.

Dealing with equality and benefit for water allocation in a lake watershed: A Gini-coefficient based stochastic optimization approach

NASA Astrophysics Data System (ADS)

Dai, C.; Qin, X. S.; Chen, Y.; Guo, H. C.

2018-06-01

A Gini-coefficient based stochastic optimization (GBSO) model was developed by integrating the hydrological model, water balance model, Gini coefficient and chance-constrained programming (CCP) into a general multi-objective optimization modeling framework for supporting water resources allocation at a watershed scale. The framework was advantageous in reflecting the conflicting equity and benefit objectives for water allocation, maintaining the water balance of watershed, and dealing with system uncertainties. GBSO was solved by the non-dominated sorting Genetic Algorithms-II (NSGA-II), after the parameter uncertainties of the hydrological model have been quantified into the probability distribution of runoff as the inputs of CCP model, and the chance constraints were converted to the corresponding deterministic versions. The proposed model was applied to identify the Pareto optimal water allocation schemes in the Lake Dianchi watershed, China. The optimal Pareto-front results reflected the tradeoff between system benefit (αSB) and Gini coefficient (αG) under different significance levels (i.e. q) and different drought scenarios, which reveals the conflicting nature of equity and efficiency in water allocation problems. A lower q generally implies a lower risk of violating the system constraints and a worse drought intensity scenario corresponds to less available water resources, both of which would lead to a decreased system benefit and a less equitable water allocation scheme. Thus, the proposed modeling framework could help obtain the Pareto optimal schemes under complexity and ensure that the proposed water allocation solutions are effective for coping with drought conditions, with a proper tradeoff between system benefit and water allocation equity.

Nanoporous biomaterials for uremic toxin adsorption in artificial kidney systems: A review.

PubMed

Cheah, Wee-Keat; Ishikawa, Kunio; Othman, Radzali; Yeoh, Fei-Yee

2017-07-01

Hemodialysis, one of the earliest artificial kidney systems, removes uremic toxins via diffusion through a semipermeable porous membrane into the dialysate fluid. Miniaturization of the present hemodialysis system into a portable and wearable device to maintain continuous removal of uremic toxins would require that the amount of dialysate used within a closed-system is greatly reduced. Diffused uremic toxins within a closed-system dialysate need to be removed to maintain the optimum concentration gradient for continuous uremic toxin removal by the dialyzer. In this dialysate regenerative system, adsorption of uremic toxins by nanoporous biomaterials is essential. Throughout the years of artificial kidney development, activated carbon has been identified as a potential adsorbent for uremic toxins. Adsorption of uremic toxins necessitates nanoporous biomaterials, especially activated carbon. Nanoporous biomaterials are also utilized in hemoperfusion for uremic toxin removal. Further miniaturization of artificial kidney system and improvements on uremic toxin adsorption capacity would require high performance nanoporous biomaterials which possess not only higher surface area, controlled pore size, but also designed architecture or structure and surface functional groups. This article reviews on various nanoporous biomaterials used in current artificial kidney systems and several emerging nanoporous biomaterials. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1232-1240, 2017. © 2016 Wiley Periodicals, Inc.

New Developments in Hepatorenal Syndrome.

PubMed

Mindikoglu, Ayse L; Pappas, Stephen C

2018-02-01

Hepatorenal syndrome (HRS) continues to be one of the major complications of decompensated cirrhosis, leading to death in the absence of liver transplantation. Challenges in precisely evaluating renal function in the patient with cirrhosis remain because of the limitations of serum creatinine (Cr) alone in estimating glomerular filtration rate (GFR); current GFR estimating models appear to underestimate renal dysfunction. Newer models incorporating renal biomarkers, such as the Cr-Cystatin C GFR Equation for Cirrhosis appear to estimate measured GFR more accurately. A major change in the diagnostic criteria for HRS based on dynamic serial changes in serum Cr that regard HRS type 1 as a special form of acute kidney injury promises the possibility of earlier identification of renal dysfunction in patients with cirrhosis. The diagnostic criteria of HRS still include the exclusion of other causes of kidney injury. Renal biomarkers have been disappointing in assisting with the differentiation of HRS from prerenal azotemia and other kidney disorders. Serum metabolomic profiling may be a more powerful tool to assess renal dysfunction, although the practical clinical significance of this remains unclear. As a result of the difficulties of assessing renal function in cirrhosis and the varying HRS diagnostic criteria and the rigor with which they are applied, the precise incidence and prevalence of HRS is unknown, but it is likely that HRS occurs more commonly than expected. The pathophysiology of HRS is rooted firmly in the setting of progressive reduction in renal blood flow as a result of portal hypertension and splanchnic vasodilation. Progressive marked renal cortical ischemia in patients with cirrhosis parallels the evolution of diuretic-sensitive ascites to diuretic-refractory ascites and HRS, a recognized continuum of renal dysfunction in cirrhosis. Alterations in nitrous oxide production, both increased and decreased, may play a major role in the pathophysiology of this evolution. The inflammatory cascade, triggered by bacterial translocation and endotoxemia, increasingly recognized as important in the manifestation of acute-on-chronic liver failure, also may play a significant role in the pathophysiology of HRS. The mainstay of treatment remains vasopressor therapy with albumin in an attempt to reverse splanchnic vasodilation and improve renal blood flow. Several meta-analyses have confirmed the value of vasopressors, chiefly terlipressin and noradrenaline, in improving renal function and reversing HRS type 1. Other interventions such as renal replacement therapy, transjugular intrahepatic portosystemic shunt, and artificial liver support systems have a very limited role in improving outcomes in HRS. Liver transplantation remains the definitive treatment for HRS. The frequency of simultaneous liver-kidney transplantation has increased dramatically in the Model for End-stage Liver Disease era, with changes in organ allocation policies. This has resulted in a more urgent need to predict native kidney recovery from HRS after liver transplantation alone, to avoid unnecessary simultaneous liver-kidney transplantation. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

77 FR 30540 - Center for Scientific Review Notice of Closed Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-23

... Committee: Center for Scientific Review Special Emphasis Panel; Drug Discovery for the Nervous System...: Digestive, Kidney and Urological Systems Integrated Review Group; Kidney Molecular Biology and Genitourinary...

Belatacept Injection

MedlinePlus

... rejection (attack of a transplanted organ by the immune system of a person receiving the organ) of kidney ... It works by decreasing the activity of the immune system to prevent it from attacking the transplanted kidney.

Investigation of Optimal Control Allocation for Gust Load Alleviation in Flight Control

NASA Technical Reports Server (NTRS)

Frost, Susan A.; Taylor, Brian R.; Bodson, Marc

2012-01-01

Advances in sensors and avionics computation power suggest real-time structural load measurements could be used in flight control systems for improved safety and performance. A conventional transport flight control system determines the moments necessary to meet the pilot's command, while rejecting disturbances and maintaining stability of the aircraft. Control allocation is the problem of converting these desired moments into control effector commands. In this paper, a framework is proposed to incorporate real-time structural load feedback and structural load constraints in the control allocator. Constrained optimal control allocation can be used to achieve desired moments without exceeding specified limits on monitored load points. Minimization of structural loads by the control allocator is used to alleviate gust loads. The framework to incorporate structural loads in the flight control system and an optimal control allocation algorithm will be described and then demonstrated on a nonlinear simulation of a generic transport aircraft with flight dynamics and static structural loads.

Profile, risk factors and outcome of acute kidney injury in paediatric acute-on-chronic liver failure.

PubMed

Lal, Bikrant B; Alam, Seema; Sood, Vikrant; Rawat, Dinesh; Khanna, Rajeev

2018-01-11

There are no studies on acute kidney injury in paediatric acute-on-chronic liver failure. This study was planned with aim to describe the clinical presentation and outcome of acute kidney injury among paediatric acute-on-chronic liver failure patients. Data of all children 1-18 years of age presenting with acute chronic liver failure (Asia pacific association for the study of the liver definition) was reviewed. Acute kidney injury was defined as per Kidney Diseases-Improving Global Outcomes guidelines. Poor outcome was defined as death or need for liver transplant within 3 months of development of acute kidney injury. A total of 84 children with acute-on-chronic liver failure were presented to us in the study period. Acute kidney injury developed in 22.6% of patients with acute-on-chronic liver failure. The median duration from acute-on-chronic liver failure to development of acute kidney injury was 4 weeks (Range: 2-10 weeks). The causes of acute kidney injury were hepatorenal syndrome (31.6%), sepsis (31.6%), nephrotoxic drugs (21%), dehydration (10.5%) and bile pigment related acute tubular necrosis in one patient. On univariate analysis, higher baseline bilirubin, higher international normalized ratio, higher paediatric end stage liver disease, presence of systemic inflammatory response syndrome and presence of spontaneous bacterial peritonitis had significant association with presence of acute kidney injury. On logistic regression analysis, presence of systemic inflammatory response syndrome (adjusted OR: 8.659, 95% CI: 2.18-34.37, P = .002) and higher baseline bilirubin (adjusted OR: 1.07, 95% CI: 1.008-1.135, P = .025) were independently associated with presence of acute kidney injury. Of the patients with acute kidney injury, 5(26.3%) survived with native liver, 10(52.6%) died and 4 (21.1%) underwent liver transplantation. Acute kidney injury developed in 22.6% of children with acute-on-chronic liver failure. Bilirubin more than 17.7 mg/dL and presence of systemic inflammatory response syndrome were high risk factors for acute kidney injury. Development of acute kidney injury in a child with acute-on-chronic liver failure suggests poor outcome and need for early intervention. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Equalizing Matching Grants and the Allocative and Distributive Objectives of Public School Financing

ERIC Educational Resources Information Center

Gatti, James F.; Tashman, Leonard J.

1976-01-01

Argues that typical Equalizing Matching Grant (EMG) systems for distributing state school aid cannot be expected to achieve the allocative and distributive goals of school finance. Derives a generalized EMG system and specific school aid formula that satisfy the allocative and distributive criteria. Available from: NTA-TIA, 21 East State Street,…

Effect of Early Vasopressin vs Norepinephrine on Kidney Failure in Patients With Septic Shock: The VANISH Randomized Clinical Trial.

PubMed

Gordon, Anthony C; Mason, Alexina J; Thirunavukkarasu, Neeraja; Perkins, Gavin D; Cecconi, Maurizio; Cepkova, Magda; Pogson, David G; Aya, Hollmann D; Anjum, Aisha; Frazier, Gregory J; Santhakumaran, Shalini; Ashby, Deborah; Brett, Stephen J

2016-08-02

Norepinephrine is currently recommended as the first-line vasopressor in septic shock; however, early vasopressin use has been proposed as an alternative. To compare the effect of early vasopressin vs norepinephrine on kidney failure in patients with septic shock. A factorial (2×2), double-blind, randomized clinical trial conducted in 18 general adult intensive care units in the United Kingdom between February 2013 and May 2015, enrolling adult patients who had septic shock requiring vasopressors despite fluid resuscitation within a maximum of 6 hours after the onset of shock. Patients were randomly allocated to vasopressin (titrated up to 0.06 U/min) and hydrocortisone (n = 101), vasopressin and placebo (n = 104), norepinephrine and hydrocortisone (n = 101), or norepinephrine and placebo (n = 103). The primary outcome was kidney failure-free days during the 28-day period after randomization, measured as (1) the proportion of patients who never developed kidney failure and (2) median number of days alive and free of kidney failure for patients who did not survive, who experienced kidney failure, or both. Rates of renal replacement therapy, mortality, and serious adverse events were secondary outcomes. A total of 409 patients (median age, 66 years; men, 58.2%) were included in the study, with a median time to study drug administration of 3.5 hours after diagnosis of shock. The number of survivors who never developed kidney failure was 94 of 165 patients (57.0%) in the vasopressin group and 93 of 157 patients (59.2%) in the norepinephrine group (difference, -2.3% [95% CI, -13.0% to 8.5%]). The median number of kidney failure-free days for patients who did not survive, who experienced kidney failure, or both was 9 days (interquartile range [IQR], 1 to -24) in the vasopressin group and 13 days (IQR, 1 to -25) in the norepinephrine group (difference, -4 days [95% CI, -11 to 5]). There was less use of renal replacement therapy in the vasopressin group than in the norepinephrine group (25.4% for vasopressin vs 35.3% for norepinephrine; difference, -9.9% [95% CI, -19.3% to -0.6%]). There was no significant difference in mortality rates between groups. In total, 22 of 205 patients (10.7%) had a serious adverse event in the vasopressin group vs 17 of 204 patients (8.3%) in the norepinephrine group (difference, 2.5% [95% CI, -3.3% to 8.2%]). Among adults with septic shock, the early use of vasopressin compared with norepinephrine did not improve the number of kidney failure-free days. Although these findings do not support the use of vasopressin to replace norepinephrine as initial treatment in this situation, the confidence interval included a potential clinically important benefit for vasopressin, and larger trials may be warranted to assess this further. clinicaltrials.gov Identifier: ISRCTN 20769191.

Effects of Single and Combined Losartan and Tempol Treatments on Oxidative Stress, Kidney Structure and Function in Spontaneously Hypertensive Rats with Early Course of Proteinuric Nephropathy.

PubMed

Karanovic, Danijela; Grujic-Milanovic, Jelica; Miloradovic, Zoran; Ivanov, Milan; Jovovic, Djurdjica; Vajic, Una-Jovana; Zivotic, Maja; Markovic-Lipkovski, Jasmina; Mihailovic-Stanojevic, Nevena

2016-01-01

Oxidative stress has been widely implicated in both hypertension and chronic kidney disease (CKD). Hypertension is a major risk factor for CKD progression. In the present study we have investigated the effects of chronic single tempol (membrane-permeable radical scavenger) or losartan (angiotensin II type 1 receptor blocker) treatment, and their combination on systemic oxidative status (plasma thiobarbituric acid-reactive substances (pTBARS) production, plasma antioxidant capacity (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, pABTS), erythrocyte antioxidant enzymes activities) and kidney oxidative stress (kTBARS, kABTS, kidney antioxidant enzymes activities), kidney function and structure in spontaneously hypertensive rats (SHR) with the early course of adriamycin-induced nephropathy. Adult SHR were divided into five groups. The control group received vehicle, while the other groups received adriamycin (2 mg/kg, i.v.) twice in a 21-day interval, followed by vehicle, losartan (L,10 mg/kg/day), tempol (T,100 mg/kg/day) or combined T+L treatment (by gavage) during a six-week period. Adriamycin significantly increased proteinuria, plasma lipid peroxidation, kidney protein oxidation, nitrite excretion, matrix metalloproteinase-1 (MMP-1) protein expression and nestin immunostaining in the kidney. Also, it decreased kidney antioxidant defense, kidney NADPH oxidase 4 (kNox4) protein expression and abolished anti-inflammatory response due to significant reduction of kidney NADPH oxidase 2 (kNox2) protein expression in SHR. All treatments reduced protein-to-creatinine ratio (marker of proteinuria), pTBARS production, kidney protein carbonylation, nitrite excretion, increased antioxidant capacity and restored kidney nestin expression similar to control. Both single treatments significantly improved systemic and kidney antioxidant defense, bioavailability of renal nitric oxide, reduced kMMP-1 protein expression and renal injury, thus retarded CKD progression. Losartan improved blood pressure, as well as tubular injury and restored anti-inflammatory defense by reverting kNox2 expression to the control level. Interestingly, tempol was more successful in reducing systemic oxidative stress, proteinuria, kMMP-1 and glomerulosclerosis. However, combined treatment failed to overcome the beneficial effects of single treatments in slowing down the progression of ADR-induced nephropathy in SHR.

21 CFR 866.5320 - Properdin factor B immuno-logical test system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... of the glomeruli of the kidney), lupus nephritis (kidney disease associated with a multisystem autoimmune disease, systemic lupus erythematosus), as well as several skin diseases, e.g., dermititis...

Inpatient health care utilization by children and adolescents with systemic lupus erythematosus and kidney involvement.

PubMed

Tanzer, Marie; Tran, Cheryl; Messer, Kassandra L; Kroeker, Amber; Herreshoff, Emily; Wickman, Larysa; Harkness, Courtney; Song, Peter; Gipson, Debbie S

2013-03-01

To evaluate inpatient health care utilization for children with systemic lupus erythematosus (SLE) with and without kidney disease. The Healthcare Cost and Utilization Project Kids' Inpatient Database for the years 2000, 2003, and 2006 was used for this analysis. SLE hospitalizations from the 2006 cohort were identified and classified as those with versus without kidney involvement by International Classification of Diseases, Ninth Revision, Clinical Modification codes. Analyses were performed to examine determinants of hospitalization charges and changes in charges over time. In the US, 7,390 SLE-related pediatric hospitalizations generated $267 million in total charges in 2006. Of these, 4,193 discharges had kidney involvement. The average hospitalization charge was greater for SLE patients with kidney involvement compared to those without kidney involvement ($43,100 versus $28,500; P < 0.0001). In multivariate analysis, kidney involvement remained a significant predictor of hospitalization charges, independent of demographic and hospital characteristics (P < 0.0001). SLE-associated acute kidney failure, transplant, and end-stage kidney disease resulted in greater hospitalization charges than SLE without kidney involvement by $74,900 (P < 0.0001), $32,700 (P = 0.0002), and $27,400 (P < 0.0001), respectively. In the US, >7,000 hospitalizations occurred in 2006 among children with SLE, with nearly 57% demonstrating kidney involvement. Kidney involvement is a major determinant of hospitalization charges for these children. This study represents one of the first large-scale assessments of in-hospital health care utilization by children with SLE. Copyright © 2013 by the American College of Rheumatology.

Clinical Course of a Patient With Kidney Failure Due to Isolated Bilateral Renal Extramedullary Plasmacytomas.

PubMed

Lawrence, Braden J; Petersen, Emily L; Riches, Wayne G; Pfeiffer, David C

2018-06-06

Plasmacytomas are rare immunoproliferative monoclonal plasma cell diseases of lymphoid lineage that may present in an isolated or systemic manner. Systemic involvement is much more common than occurrences isolated to a particular organ, and for this reason, it is imperative to rule out systemic involvement for osseous and nonosseous isolated neoplasms. These neoplasms present unique challenges due to their location, extent of involvement, vague presentation, and dearth of treatment protocol. We report the case of a 69-year-old man who developed chronic kidney disease stage 4 between 2009 and 2012. Precipitous kidney failure, anorexia, fatigue, and flank pain necessitated clinical follow-up that ultimately led to thorough imaging and bilateral kidney biopsy. Protein electrophoresis, immunohistochemistry, and immunofluorescence were all consistent with bilateral renal extramedullary plasmacytomas. Treatment recommendations are often limited to prior case successes; however, chemotherapy, radiation, and surgery are the mainstay of treatment. Although surgery or combined therapy provides the best results for patients, such options are unfeasible with bilateral kidney involvement. Therefore, a chemotherapy regimen, similar to that for multiple myeloma, was determined to be most reasonable. Treatment consisted of 4 cycles of a bortezomib, cyclophosphamide, and dexamethasone regimen. Three months following chemotherapy, kidney function returned to baseline levels. Copyright © 2018 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Knowledge-based segmentation of pediatric kidneys in CT for measuring parenchymal volume

NASA Astrophysics Data System (ADS)

Brown, Matthew S.; Feng, Waldo C.; Hall, Theodore R.; McNitt-Gray, Michael F.; Churchill, Bernard M.

2000-06-01

The purpose of this work was to develop an automated method for segmenting pediatric kidneys in contrast-enhanced helical CT images and measuring the volume of the renal parenchyma. An automated system was developed to segment the abdomen, spine, aorta and kidneys. The expected size, shape, topology an X-ray attenuation of anatomical structures are stored as features in an anatomical model. These features guide 3-D threshold-based segmentation and then matching of extracted image regions to anatomical structures in the model. Following segmentation, the kidney volumes are calculated by summing included voxels. To validate the system, the kidney volumes of 4 swine were calculated using our approach and compared to the 'true' volumes measured after harvesting the kidneys. Automated volume calculations were also performed retrospectively in a cohort of 10 children. The mean difference between the calculated and measured values in the swine kidneys was 1.38 (S.D. plus or minus 0.44) cc. For the pediatric cases, calculated volumes ranged from 41.7 - 252.1 cc/kidney, and the mean ratio of right to left kidney volume was 0.96 (S.D. plus or minus 0.07). These results demonstrate the accuracy of the volumetric technique that may in the future provide an objective assessment of renal damage.

Evaluation of Sub-acute Oral Toxicity of Lithium Carbonate Microemulsion (Nano Size) on Liver and Kidney of Mice

PubMed Central

Kalantari, Heibatullah; Salimi, Anayatollah; Rezaie, Anahita; Jazayeri Shushtari, Fereshteh; Goudarzi, Mehdi

2015-01-01

Background: The development of drug delivery systems has improved the therapeutic and toxic properties of existing drugs in therapy. Microemulsion systems are novel vehicles for drug delivery, which have been developed in recent years. These systems are currently of interest to the pharmaceutical scientist because of their considerable potential to act as drug delivery vehicles by incorporating into a wide range of drug molecules. Although these systems improved solubility and bioavailability of drugs, they may have potential toxic effects on the body organs. Objectives: The purpose of this study was to examine a possible hepatotoxic and nephrotoxic effect of lithium carbonate microemulsion (LCME) in a mice model. Materials and Methods: Eighty male Swiss albino mice were randomly allocated to eight experimental groups, as follows: Group 1, as negative control group were treated orally with normal saline (0.9% NaCl); Group 2, received microemulsion base without drug as control group; Groups 3 to 5, received lithium carbonate (LC) solution in doses of 50, 100, and 200 mg/kg, respectively; Groups 6 to 8, received LCME orally in doses of 50, 100, and 200 mg/kg, respectively. All drugs were administered orally for ten consecutive days. Serum glutamate pyruvate aminotransferase (SGPT), serum glutamate oxaloacetate aminotransferase (SGOT), alkaline phosphatase (ALP), blood urea nitrogen (BUN), and plasma creatinine (Cr), as markers of liver and kidney toxicity in treated mice, were measured. Furthermore, the changes of tissue were assessed by histopathologic examination. Results: The findings showed that serum activity of ALP, SGOT, and SGPT and the levels of BUN and Cr in microemulsion base group was greater than normal saline group. However, this difference was not significant. Administration of LC and LCME in all doses resulted in a significant increase in the levels of BUN and serum activity of SGOT and SGPT in comparison to normal saline group (P < 0.05). Histopathological changes were observed in mice treated with LC or LCME. Conclusions: This study showed that subacute oral administration of different doses of LCME with severe toxicity in comparison to the same dose of LC. PMID:25866723

The case for living kidney sales: rationale, objections and concerns.

PubMed

Matas, Arthur J

2004-12-01

Currently, potential kidney transplant candidates are dying on the waiting list. One potential solution would be a regulated system of living kidney sales (with safeguards to protect the vendor). Potential objections and practical concerns are discussed.

Kidney biopsy

MedlinePlus

... normal structure. What Abnormal Results Mean An abnormal result means there are changes in the kidney tissue. This may be due to: Infection Poor blood flow through the kidney Connective tissue diseases such as systemic lupus erythematosus Other diseases that may be affecting the ...

Of Inflammasomes and Alarmins: IL-1β and IL-1α in Kidney Disease

PubMed Central

2016-01-01

Kidney injury implies danger signaling and a response by the immune system. The inflammasome is a central danger recognition platform that triggers local and systemic inflammation. In immune cells, inflammasome activation causes the release of mature IL-1β and of the alarmin IL-1α. Dying cells release IL-1α also, independently of the inflammasome. Both IL-1α and IL-1β ligate the same IL-1 receptor (IL-1R) that is present on nearly all cells inside and outside the kidney, further amplifying cytokine and chemokine release. Thus, the inflammasome-IL-1α/IL-β-IL-1R system is a central element of kidney inflammation and the systemic consequences. Seminal discoveries of recent years have expanded this central paradigm of inflammation. This review gives an overview of arising concepts of inflammasome and IL-1α/β regulation in renal cells and in experimental kidney disease models. There is a pipeline of compounds that can interfere with the inflammasome-IL-1α/IL-β-IL-1R system, ranging from recently described small molecule inhibitors of NLRP3, a component of the inflammasome complex, to regulatory agency–approved IL-1–neutralizing biologic drugs. Based on strong theoretic and experimental rationale, the potential therapeutic benefits of using such compounds to block the inflammasome-IL-1α/IL-β-IL-1R system in kidney disease should be further explored. PMID:27516236

Uteroplacental insufficiency temporally exacerbates salt-induced hypertension associated with a reduced natriuretic response in male rat offspring.

PubMed

Gallo, Linda A; Walton, Sarah L; Mazzuca, Marc Q; Tare, Marianne; Parkington, Helena C; Wlodek, Mary E; Moritz, Karen M

2018-03-31

Low weight at birth increases the risk of developing chronic diseases in adulthood A diet that is high in salt is known to elevate blood pressure, which is a major risk factor for cardiovascular and kidney diseases The present study demonstrates that growth restricted male rats have a heightened sensitivity to high dietary salt, in the context of raised systolic blood pressure, reduced urinary sodium excretion and stiffer mesenteric resistance vessels Other salt-induced effects, such as kidney hyperfiltration, albuminuria and glomerular damage, were not exacerbated by being born small The present study demonstrates that male offspring born small have an increased cardiovascular susceptibility to high dietary salt, such that that minimizing salt intake is probably of particular benefit to this at-risk population ABSTRACT: Intrauterine growth restriction increases the risk of developing chronic diseases in adulthood. Lifestyle factors, such as poor dietary choices, may elevate this risk. We determined whether being born small increases the sensitivity to a dietary salt challenge, in the context of hypertension, kidney disease and arterial stiffness. Bilateral uterine vessel ligation or sham surgery (offspring termed Restricted and Control, respectively) was performed on 18-day pregnant Wistar Kyoto rats. Male offspring were allocated to receive a diet high in salt (8% sodium chloride) or remain on standard rat chow (0.52% sodium chloride) from 20 to 26 weeks of age for 6 weeks. Systolic blood pressure (tail-cuff), renal function (24 h urine excretions) and vascular stiffness (pressure myography) were assessed. Restricted males were born 15% lighter than Controls and remained smaller throughout the study. Salt-induced hypertension was exacerbated in Restricted offspring, reaching a peak systolic pressure of ∼175 mmHg earlier than normal weight counterparts. The natriuretic response to high dietary salt in Restricted animals was less than in Controls and may explain the early rise in arterial pressure. Growth restricted males allocated to a high salt diet also had increased passive arterial stiffness of mesenteric resistance arteries. Other aspects of renal function, including salt-induced hyperfiltration, albuminuria and glomerular damage, were not exacerbated by uteroplacental insufficiency. The present study demonstrates that male offspring exposed to uteroplacental insufficiency and born small have an increased sensitivity to salt-induced hypertension and arterial remodelling. © 2018 The Authors. The Journal of Physiology © 2018 The Physiological Society.

A proposed new classification for the renal collecting system of cattle.

PubMed

Pereira-Sampaio, Marco A; Bagetti Filho, Helio J S; Carvalho, Francismar S; Sampaio, Francisco J B; Henry, Robert W

2010-11-01

To evaluate the intrarenal anatomy of kidneys obtained from cattle and to propose a new classification for the renal collecting system of cattle. 37 kidneys from 20 adult male mixed-breed cattle. Intrarenal anatomy was evaluated by the use of 3-D endocasts made of the kidneys. The number of renal lobes and minor renal calyces in each kidney and each renal region (cranial pole, caudal pole, and hilus) was quantified. The renal pelvis was evident in all casts and was classified into 2 types (nondilated [28/37 {75.7%}] or dilated [9/37 {24.3%}]). All casts had a major renal calyx associated with the cranial pole and the caudal pole. The number of minor renal calices per kidney ranged from 13 to 64 (mean, 22.7). There was a significant correlation between the number of renal lobes and the number of minor renal calices for the entire kidney, the cranial pole region, and the hilus region; however, there was not a similar significant correlation for the caudal pole region. Major and minor renal calices were extremely narrow, compared with major and minor renal calices in pigs and humans. The renal collecting system of cattle, with a renal pelvis and 2 major renal calices connected to several minor renal calices by an infundibulum, differed substantially from the renal collecting system of pigs and humans. From a morphological standpoint, the kidneys of cattle were not suitable for use as a model in endourologic research and training.

Optimum allocation of redundancy among subsystems connected in series. Ph.D. Thesis - Case Western Reserve Univ., Sep. 1970

NASA Technical Reports Server (NTRS)

Bien, D. D.

1973-01-01

This analysis considers the optimum allocation of redundancy in a system of serially connected subsystems in which each subsystem is of the k-out-of-n type. Redundancy is optimally allocated when: (1) reliability is maximized for given costs; or (2) costs are minimized for given reliability. Several techniques are presented for achieving optimum allocation and their relative merits are discussed. Approximate solutions in closed form were attainable only for the special case of series-parallel systems and the efficacy of these approximations is discussed.

Summary of Research 1997 Department of Systems Management.

DTIC Science & Technology

1999-01-01

formulation and execution; impacts of budget allocation , reallocation, and reduction; imple- mentation of Defense Resource Management Systems; and the...flexible structure that can be applied to a wide range of resource allocation problems. PUBLICATIONS: Dolk, D., Murphy, M., and Thomas, G...policies, procedures, and rationale in deter- mining recruiting resource allocation decisions. The methodology relies on a review of the literature

Optimal allocation model of construction land based on two-level system optimization theory

NASA Astrophysics Data System (ADS)

Liu, Min; Liu, Yanfang; Xia, Yuping; Lei, Qihong

2007-06-01

The allocation of construction land is an important task in land-use planning. Whether implementation of planning decisions is a success or not, usually depends on a reasonable and scientific distribution method. Considering the constitution of land-use planning system and planning process in China, multiple levels and multiple objective decision problems is its essence. Also, planning quantity decomposition is a two-level system optimization problem and an optimal resource allocation decision problem between a decision-maker in the topper and a number of parallel decision-makers in the lower. According the characteristics of the decision-making process of two-level decision-making system, this paper develops an optimal allocation model of construction land based on two-level linear planning. In order to verify the rationality and the validity of our model, Baoan district of Shenzhen City has been taken as a test case. Under the assistance of the allocation model, construction land is allocated to ten townships of Baoan district. The result obtained from our model is compared to that of traditional method, and results show that our model is reasonable and usable. In the end, the paper points out the shortcomings of the model and further research directions.

The systemic nature of CKD.

PubMed

Zoccali, Carmine; Vanholder, Raymond; Massy, Ziad A; Ortiz, Alberto; Sarafidis, Pantelis; Dekker, Friedo W; Fliser, Danilo; Fouque, Denis; Heine, Gunnar H; Jager, Kitty J; Kanbay, Mehmet; Mallamaci, Francesca; Parati, Gianfranco; Rossignol, Patrick; Wiecek, Andrzej; London, Gerard

2017-06-01

The accurate definition and staging of chronic kidney disease (CKD) is one of the major achievements of modern nephrology. Intensive research is now being undertaken to unravel the risk factors and pathophysiologic underpinnings of this disease. In particular, the relationships between the kidney and other organs have been comprehensively investigated in experimental and clinical studies in the last two decades. Owing to technological and analytical limitations, these links have been studied with a reductionist approach focusing on two organs at a time, such as the heart and the kidney or the bone and the kidney. Here, we discuss studies that highlight the complex and systemic nature of CKD. Energy balance, innate immunity and neuroendocrine signalling are highly integrated biological phenomena. The diseased kidney disrupts such integration and generates a high-risk phenotype with a clinical profile encompassing inflammation, protein-energy wasting, altered function of the autonomic and central nervous systems and cardiopulmonary, vascular and bone diseases. A systems biology approach to CKD using omics techniques will hopefully enable in-depth study of the pathophysiology of this systemic disease, and has the potential to unravel critical pathways that can be targeted for CKD prevention and therapy.

Is Fibroblast growth factor 23 the leading cause of increased mortality among chronic kidney disease patients? A narrative review.

PubMed

Sharaf El Din, Usama A; Salem, Mona M; Abdulazim, Dina O

2017-05-01

The death rate among chronic kidney disease patients is the highest compared to other chronic diseases. 60% of these fatalities are cardiovascular. Cardiovascular calcifications and chronic inflammation affect almost all chronic kidney disease patients and are associated with cardiovascular mortality. Fibroblast growth factor 23 is associated with vascular calcification. Systemic inflammation in chronic kidney disease patients is multifactorial. The role of systemic inflammation in the pathogenesis of vascular calcification was recently reappraised. Fibroblast growth factor 23 was accused as a direct stimulus of left ventricular hypertrophy, uremic inflammation, and impaired neutrophil function. This review will discuss the underlying mechanisms that underlie the link between Fibroblast growth factor 23 and increased mortality encountered among chronic kidney disease patients.

Aboveground Tree Growth Varies with Belowground Carbon Allocation in a Tropical Rainforest Environment

PubMed Central

Raich, James W.; Clark, Deborah A.; Schwendenmann, Luitgard; Wood, Tana E.

2014-01-01

Young secondary forests and plantations in the moist tropics often have rapid rates of biomass accumulation and thus sequester large amounts of carbon. Here, we compare results from mature forest and nearby 15–20 year old tree plantations in lowland Costa Rica to evaluate differences in allocation of carbon to aboveground production and root systems. We found that the tree plantations, which had fully developed, closed canopies, allocated more carbon belowground - to their root systems - than did mature forest. This increase in belowground carbon allocation correlated significantly with aboveground tree growth but not with canopy production (i.e., leaf fall or fine litter production). In contrast, there were no correlations between canopy production and either tree growth or belowground carbon allocation. Enhanced allocation of carbon to root systems can enhance plant nutrient uptake, providing nutrients beyond those required for the production of short-lived tissues such as leaves and fine roots, and thus enabling biomass accumulation. Our analyses support this deduction at our site, showing that enhanced allocation of carbon to root systems can be an important mechanism promoting biomass accumulation during forest growth in the moist tropics. Identifying factors that control when, where and for how long this occurs would help us to improve models of forest growth and nutrient cycling, and to ascertain the role that young forests play in mitigating increased atmospheric carbon dioxide. PMID:24945351

Hybrid Resource Allocation Scheme with Proportional Fairness in OFDMA-Based Cognitive Radio Systems

NASA Astrophysics Data System (ADS)

Li, Li; Xu, Changqing; Fan, Pingzhi; He, Jian

In this paper, the resource allocation problem for proportional fairness in hybrid Cognitive Radio (CR) systems is studied. In OFDMA-based CR systems, traditional resource allocation algorithms can not guarantee proportional rates among CR users (CRU) in each OFDM symbol because the number of available subchannels might be smaller than that of CRUs in some OFDM symbols. To deal with this time-varying nature of available spectrum resource, a hybrid CR scheme in which CRUs are allowed to use subchannels in both spectrum holes and primary users (PU) bands is adopted and a resource allocation algorithm is proposed to guarantee proportional rates among CRUs with no undue interference to PUs.

Power allocation and range performance considerations for a dual-frequency EBPSK/MPPSK system

NASA Astrophysics Data System (ADS)

Yao, Yu; Wu, Lenan; Zhao, Junhui

2017-12-01

Extended binary phase shift keying/M-ary position phase shift keying (EBPSK/MPPSK)-MODEM provides radar and communication functions on a single hardware platform with a single waveform. However, its range estimation accuracy is worse than continuous-wave (CW) radar because of the imbalance of power in two carrier frequencies. In this article, the power allocation method for dual-frequency EBPSK/MPPSK modulated systems is presented. The power of two signal transmitters is adequately allocated to ensure that the power in two carrier frequencies is equal. The power allocation ratios for two types of modulation systems are obtained. Moreover, considerations regarding the range of operation of the dual-frequency system are analysed. In addition to theoretical considerations, computer simulations are provided to illustrate the performance.

Quantitative Enzymatic and Immunologic Histophotometry of Diseased Human Kid-Ney Tissues Using Tv-Camera and Computer Assisted Image Processing Systems.

NASA Astrophysics Data System (ADS)

Heinert, G.; Mondorf, W.

1982-11-01

High speed image processing was used to analyse morphologic and metabolic characteristics of clinically relevant kidney tissue alterations.Qualitative computer-assisted histophotometry was performed to measure alterations in levels of the enzymes alkaline phosphatase (Ap),alanine aminopeptidase (AAP),g-glutamyltranspepti-dase (GGTP) and A-glucuronidase (B-G1) and AAP and GGTP immunologically determined in prepared renal and cancer tissue sections. A "Mioro-Videomat 2" image analysis system with a "Tessovar" macroscope,a computer-assisted "Axiomat" photomicroscope and an "Interactive Image Analysis System (IBAS)" were employed for analysing changes in enzyme activities determined by changes in absorbance or transmission.Diseased kidney as well as renal neoplastic tissues could be distinguished by significantly (wilcoxon test,p<0,05) decreased enzyme concentrations as compared to those found in normal human kidney tissues.This image analysis techniques might be of potential use in diagnostic and prognostic evaluation of renal cancer and diseased kidney tissues.

The Immune System in Hypertension

ERIC Educational Resources Information Center

Trott, Daniel W.; Harrison, David G.

2014-01-01

While hypertension has predominantly been attributed to perturbations of the vasculature, kidney, and central nervous system, research for almost 50 yr has shown that the immune system also contributes to this disease. Inflammatory cells accumulate in the kidneys and vasculature of humans and experimental animals with hypertension and likely…

Ground data systems resource allocation process

NASA Technical Reports Server (NTRS)

Berner, Carol A.; Durham, Ralph; Reilly, Norman B.

1989-01-01

The Ground Data Systems Resource Allocation Process at the Jet Propulsion Laboratory provides medium- and long-range planning for the use of Deep Space Network and Mission Control and Computing Center resources in support of NASA's deep space missions and Earth-based science. Resources consist of radio antenna complexes and associated data processing and control computer networks. A semi-automated system was developed that allows operations personnel to interactively generate, edit, and revise allocation plans spanning periods of up to ten years (as opposed to only two or three weeks under the manual system) based on the relative merit of mission events. It also enhances scientific data return. A software system known as the Resource Allocation and Planning Helper (RALPH) merges the conventional methods of operations research, rule-based knowledge engineering, and advanced data base structures. RALPH employs a generic, highly modular architecture capable of solving a wide variety of scheduling and resource sequencing problems. The rule-based RALPH system has saved significant labor in resource allocation. Its successful use affirms the importance of establishing and applying event priorities based on scientific merit, and the benefit of continuity in planning provided by knowledge-based engineering. The RALPH system exhibits a strong potential for minimizing development cycles of resource and payload planning systems throughout NASA and the private sector.

[Efficiency of Brazilian States and the Federal District in the public kidney transplant system based on DEA (Data Envelopment Analysis) and the Malmquist index].

PubMed

Costa, Cassia Kely Favoretto; Balbinotto Neto, Giácomo; Sampaio, Luciano Menezes Bezerra

2014-08-01

The objective of this study was to evaluate the efficiency of Brazilian States and the Federal District in the public kidney transplant system and their productivity trends from 2006 to 2011. The authors used Data Envelopment Analysis (DEA) with slack and the Malmquist index with slack. Inputs included spending on hospital services and health professionals in the system. The output was the number of kidney transplants performed in each State. The data showed a significant discrepancy between States in the number of kidney transplants. The transplant system's inefficiency may result from inadequate management, failure to comply with national guidelines, inactive hospital transplant committees, and overburdened hospital staff. Institutional changes promoted by the Brazilian Ministry of Health (procedures improvement and standardization) failed to increase productivity in most States during this period.

Legal institutions for the allocation of water and their impact on coal conversion operations in Kentucky. Research report

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

Ausness, R.C.; Callahan, G.W.; Dills, S.W.

1976-08-01

Coal conversion plants require large quantities of water for cooling purposes and for use as a raw material. Three types of water allocation are presently used in the United States: riparianism, prior appropriation, and administrative permit systems. Kentucky presently has such a system of administrative allocation and this is described in the report. (GRA)

Allocating SMART Reliability and Maintainability Goals to NASA Ground Systems

NASA Technical Reports Server (NTRS)

Gillespie, Amanda; Monaghan, Mark

2013-01-01

This paper will describe the methodology used to allocate Reliability and Maintainability (R&M) goals to Ground Systems Development and Operations (GSDO) subsystems currently being designed or upgraded.

Mesenchymal Stem Cell-Based Therapy for Kidney Disease: A Review of Clinical Evidence

PubMed Central

2016-01-01

Mesenchymal stem cells form a population of self-renewing, multipotent cells that can be isolated from several tissues. Multiple preclinical studies have demonstrated that the administration of exogenous MSC could prevent renal injury and could promote renal recovery through a series of complex mechanisms, in particular via immunomodulation of the immune system and release of paracrine factors and microvesicles. Due to their therapeutic potentials, MSC are being evaluated as a possible player in treatment of human kidney disease, and an increasing number of clinical trials to assess the safety, feasibility, and efficacy of MSC-based therapy in various kidney diseases have been proposed. In the present review, we will summarize the current knowledge on MSC infusion to treat acute kidney injury, chronic kidney disease, diabetic nephropathy, focal segmental glomerulosclerosis, systemic lupus erythematosus, and kidney transplantation. The data obtained from these clinical trials will provide further insight into safety, feasibility, and efficacy of MSC-based therapy in renal pathologies and allow the design of consensus protocol for clinical purpose. PMID:27721835

Cardio-renal syndromes: from foggy bottoms to sunny hills.

PubMed

Ronco, Claudio

2011-11-01

"Cardio-renal syndromes" (CRS) are disorders of the heart and kidneys whereby acute or chronic dysfunction in one organ may induce acute or chronic dysfunction of the other. The current definition has been expanded into five subtypes whose etymology reflects the primary and secondary pathology, the time-frame and simultaneous cardiac and renal co-dysfunction secondary to systemic disease: CRS type I: acute worsening of heart function (AHF-ACS) leading to kidney injury and/or dysfunction. CRS type II: chronic abnormalities in heart function (CHF-CHD) leading to kidney injury or dysfunction. CRS type III: acute worsening of kidney function (AKI) leading to heart injury and/or dysfunction. CRS type IV: chronic kidney disease (CKD) leading to heart injury, disease and/or dysfunction. CRS type V: systemic conditions leading to simultaneous injury and/or dysfunction of heart and kidney. These different subtypes may have a different pathophysiological mechanism and they may represent separate entities in terms of prevention and therapy.

Enhancing effect of Fe2+ on the formaldehyde production from trimethylamine N-oxide decomposition catalyzed by the extract of Harpadon nehereus kidney

NASA Astrophysics Data System (ADS)

Sun, Yong; Zhou, Deqing; Zhao, Feng

2011-03-01

The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research. The activity of the kidney extract was presumably inhibited by ethylene diamine tetra-acetic acid (EDTA), which indicates that the kidney extract contains an enzyme or enzyme system with metal cations as activator. Activity of the kidney extract was enhanced significantly when Fe2+ was added into the model system in vitro. As the concentration of Fe2+ increased, the decomposing rate of TMAO increased rapidly until TMAO decomposed completely. The activity of the kidney extract was also enhanced by reductant such as ascorbic acid. Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) was employed to determine the content of total iron in a number of fishery products. Significant positive correlation between the contents of total iron and endogenous formaldehyde (FA) was found, especially in marine products.

Multiple Leader Candidate and Competitive Position Allocation for Robust Formation against Member Robot Faults

PubMed Central

Kwon, Ji-Wook; Kim, Jin Hyo; Seo, Jiwon

2015-01-01

This paper proposes a Multiple Leader Candidate (MLC) structure and a Competitive Position Allocation (CPA) algorithm which can be applicable for various applications including environmental sensing. Unlike previous formation structures such as virtual-leader and actual-leader structures with position allocation including a rigid allocation and an optimization based allocation, the formation employing the proposed MLC structure and CPA algorithm is robust against the fault (or disappearance) of the member robots and reduces the entire cost. In the MLC structure, a leader of the entire system is chosen among leader candidate robots. The CPA algorithm is the decentralized position allocation algorithm that assigns the robots to the vertex of the formation via the competition of the adjacent robots. The numerical simulations and experimental results are included to show the feasibility and the performance of the multiple robot system employing the proposed MLC structure and the CPA algorithm. PMID:25954956

A Framework for Optimal Control Allocation with Structural Load Constraints

NASA Technical Reports Server (NTRS)

Frost, Susan A.; Taylor, Brian R.; Jutte, Christine V.; Burken, John J.; Trinh, Khanh V.; Bodson, Marc

2010-01-01

Conventional aircraft generally employ mixing algorithms or lookup tables to determine control surface deflections needed to achieve moments commanded by the flight control system. Control allocation is the problem of converting desired moments into control effector commands. Next generation aircraft may have many multipurpose, redundant control surfaces, adding considerable complexity to the control allocation problem. These issues can be addressed with optimal control allocation. Most optimal control allocation algorithms have control surface position and rate constraints. However, these constraints are insufficient to ensure that the aircraft's structural load limits will not be exceeded by commanded surface deflections. In this paper, a framework is proposed to enable a flight control system with optimal control allocation to incorporate real-time structural load feedback and structural load constraints. A proof of concept simulation that demonstrates the framework in a simulation of a generic transport aircraft is presented.

KIR and HLA-C Interactions Promote Differential Dendritic Cell Maturation and Is a Major Determinant of Graft Failure following Kidney Transplantation

PubMed Central

Hanvesakul, Raj; Kubal, Chandrashekhar; Moore, Jason; Neil, Desley; Cook, Mark; Ball, Simon; Briggs, David; Moss, Paul; Cockwell, Paul

2011-01-01

Background HLA-C is an important ligand for killer immunoglobulin like receptors (KIR) that regulate natural killer (NK) cell function. Based on KIR specificity HLA-C molecules are allocated into two groups, HLA-C1 or HLA-C2; HLA-C2 is more inhibiting to NK cell function than HLA-C1. We studied the clinical importance of HLA-C genotypes on the long-term graft survival of 760 kidney transplants performed at our centre utilising a population based genetic study and cell culture model to define putative mechanisms. Methods and Findings Genotyping was performed using conventional DNA PCR techniques and correlations made to clinical outcomes. We found that transplant recipients with HLA-C2 had significantly better long-term graft survival than transplant recipients with HLA-C1 (66% versus 44% at 10 years, log-rank p = 0.002, HR = 1.51, 95%CI = 1.16–1.97). In in-vitro NK and dendritic cell (DC) co-culture model we made several key observations that correlated with the population based genetic study. We observed that donor derived NK cells, on activation with IL-15, promoted differential HLA-C genotype dependent DC maturation. In NK-DC co-culture, the possession of HLA-C2 by DC was associated with anti-inflammatory cytokine production (IL-1RA/IL-6), diminished DC maturation (CD86, HLA-DR), and absent CCR7 expression. Conversely, possession of HLA-C1 by DC was associated with pro-inflammatory cytokine synthesis (TNF-α, IL-12p40/p70), enhanced DC maturation and up-regulation of CCR7 expression. By immunohistochemistry the presence of donor NK cells was confirmed in pre-transplant kidneys. Conclusions We propose that after kidney transplantation IL-15 activated donor derived NK cells interact with recipient DC with less activation of indirect allo-reactivity in HLA-C2 positive recipients than HLA-C1 positive recipients; this has implications for long-term graft survival. Early events following kidney transplantation involving NK-DC interaction via KIR and HLA-C immune synapse may have a central role in long-term kidney transplant outcomes. PMID:21912600

Laparoscopic versus open nephrectomy for live kidney donors.

PubMed

Wilson, Colin H; Sanni, Aliu; Rix, David A; Soomro, Naeem A

2011-11-09

Waiting lists for kidney transplantation continue to grow and live organ donation has become more important as the number of brain stem dead cadaveric organ donors continues to fall. The major disincentive to potential kidney donors is the pain and morbidity associated with open surgery. To identify the benefits and harms of using laparoscopic compared to open nephrectomy techniques to recover kidneys from live organ donors. We searched the online databases CENTRAL (in The Cochrane Library 2010, Issue 2), MEDLINE (January 1966 to January 2010) and EMBASE (January 1980 to January 2010) and handsearched textbooks and reference lists. Randomised controlled trials comparing laparoscopic donor nephrectomy (LDN) with open donor nephrectomy (ODN). Two review authors independently screened titles and abstracts for eligibility, assessed study quality, and extracted data. We contacted study authors for additional information where necessary. Six studies were identified that randomised 596 live kidney donors to either LDN or ODN arms. All studies were assessed as having low or unclear risk of bias for selection bias, allocation bias, incomplete outcome data and selective reporting bias. Four of six studies had high risk of bias for blinding. Various different combinations of techniques were used in each study, resulting in heterogeneity in the results. The conversion rate from LDN to ODN ranged from 1% to 1.8%. LDN was generally found to be associated with reduced analgesia use, shorter hospital stay, and faster return to normal physical functioning. The extracted kidney was exposed to longer warm ischaemia periods (2 to 17 minutes) with no associated short-term consequences. ODN was associated with shorter duration of procedure. For those outcomes that could be meta-analysed there were no significant differences between LDN or ODN for perioperative complications (RR 0.87, 95% CI 0.47 to 4.59), reoperations (RR 0.57, 95% CI 0.09 to 3.64), early graft loss (RR 0.31, 95% CI 0.06 to 1.48), delayed graft function (RR 1.09, 95% CI 0.52 to 2.30), acute rejection (RR 1.41, 95 % CI 0.87 to 2.27), ureteric complications (RR 1.51, 95% CI 0.69 to 3.31), kidney function at one year (SMD 0.15, 95% CI -0.11 to 0.41) or graft loss at one year (RR 0.76, 95% CI 0.15 to 3.85). LDN is associated with less pain compared with open surgery; however, there are equivalent numbers of complications and occurrences of perioperative events that require further intervention. Kidneys obtained using LDN procedures were exposed to longer warm ischaemia periods than ODN-acquired grafts, although this has not been reported as being associated with short-term consequences.

Design and protocol for the Dialysis Optimal Health Program (DOHP) randomised controlled trial.

PubMed

Knowles, Simon R; Ski, Chantal F; Langham, Robyn; O'Flaherty, Emmet; Thompson, David R; Rossell, Susan L; Moore, Gaye; Hsueh, Ya-Seng Arthur; Castle, David J

2016-09-09

Chronic kidney disease (CKD) and end-stage kidney disease (ESKD) are serious and growing health problems with enormous impact on psychological and social functioning. Despite high rates of comorbid depression and anxiety in these patient populations, and the adverse impact these have upon treatment adherence, quality of life, social connectedness and healthcare costs there has been little attention focused on the prevention or management of these problems. Thus, our aim was to evaluate the Dialysis Optimal Health Program (DOHP) that adopts a person-centred approach and engages collaborative therapy to educate and support those diagnosed with ESKD who are commencing dialysis. The study design is a randomised controlled trial. Ninety-six adult patients initiating haemodialysis or peritoneal dialysis will be randomly allocated to either the intervention (DOHP) or usual care group. Participants receiving the intervention will receive nine (8 + 1 booster session) sequential sessions based on a structured information/workbook, psychosocial and educational supports and skills building. The primary outcome measures are depression and anxiety (assessed by the Hospital Anxiety and Depression Scale; HADS). Secondary outcomes include health-related quality of life (assessed by the Kidney Disease Quality of Life instrument; KDQOL), self-efficacy (assessed by General Self-Efficacy Scale) and clinical indices (e.g. albumin and haemoglobin levels). Cost-effectiveness analysis and process evaluation will also be performed to assess the economic value and efficacy of the DOHP. Primary and secondary measures will be collected at baseline and at 3-, 6-, and 12-month follow-up time points. We believe that this innovative trial will enhance knowledge of interventions aimed at supporting patients in the process of starting dialysis, and will broaden the focus from physical symptoms to include psychosocial factors such as depression, anxiety, self-efficacy, wellbeing and community support. The outcomes associated with this study are significant in terms of enhancing an at-risk population's psychosocial health and reducing treatment-related costs and associated pressures on the healthcare system. ANZCTR no. 12615000810516 . Registered on 5 August 2015.

Effects of Single and Combined Losartan and Tempol Treatments on Oxidative Stress, Kidney Structure and Function in Spontaneously Hypertensive Rats with Early Course of Proteinuric Nephropathy

PubMed Central

Grujic-Milanovic, Jelica; Miloradovic, Zoran; Ivanov, Milan; Jovovic, Djurdjica; Vajic, Una-Jovana; Zivotic, Maja; Markovic-Lipkovski, Jasmina; Mihailovic-Stanojevic, Nevena

2016-01-01

Oxidative stress has been widely implicated in both hypertension and chronic kidney disease (CKD). Hypertension is a major risk factor for CKD progression. In the present study we have investigated the effects of chronic single tempol (membrane-permeable radical scavenger) or losartan (angiotensin II type 1 receptor blocker) treatment, and their combination on systemic oxidative status (plasma thiobarbituric acid-reactive substances (pTBARS) production, plasma antioxidant capacity (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, pABTS), erythrocyte antioxidant enzymes activities) and kidney oxidative stress (kTBARS, kABTS, kidney antioxidant enzymes activities), kidney function and structure in spontaneously hypertensive rats (SHR) with the early course of adriamycin-induced nephropathy. Adult SHR were divided into five groups. The control group received vehicle, while the other groups received adriamycin (2 mg/kg, i.v.) twice in a 21-day interval, followed by vehicle, losartan (L,10 mg/kg/day), tempol (T,100 mg/kg/day) or combined T+L treatment (by gavage) during a six-week period. Adriamycin significantly increased proteinuria, plasma lipid peroxidation, kidney protein oxidation, nitrite excretion, matrix metalloproteinase-1 (MMP-1) protein expression and nestin immunostaining in the kidney. Also, it decreased kidney antioxidant defense, kidney NADPH oxidase 4 (kNox4) protein expression and abolished anti-inflammatory response due to significant reduction of kidney NADPH oxidase 2 (kNox2) protein expression in SHR. All treatments reduced protein-to-creatinine ratio (marker of proteinuria), pTBARS production, kidney protein carbonylation, nitrite excretion, increased antioxidant capacity and restored kidney nestin expression similar to control. Both single treatments significantly improved systemic and kidney antioxidant defense, bioavailability of renal nitric oxide, reduced kMMP-1 protein expression and renal injury, thus retarded CKD progression. Losartan improved blood pressure, as well as tubular injury and restored anti-inflammatory defense by reverting kNox2 expression to the control level. Interestingly, tempol was more successful in reducing systemic oxidative stress, proteinuria, kMMP-1 and glomerulosclerosis. However, combined treatment failed to overcome the beneficial effects of single treatments in slowing down the progression of ADR-induced nephropathy in SHR. PMID:27560781

Consensus Conference on Best Practices in Live Kidney Donation: Recommendations to Optimize Education, Access, and Care

PubMed Central

Rudow, Dianne LaPointe; Hays, Rebecca; Baliga, Prabhakar; Cohen, David J.; Cooper, Matthew; Danovitch, Gabriel M.; Dew, Mary Amanda; Gordon, Elisa J.; Mandelbrot, Didier A.; McGuire, Suzanne; Milton, Jennifer; Moore, Deonna R.; Morgieivich, Marie; Schold, Jesse D.; Segev, Dorry L.; Serur, David; Steiner, Robert W.; Tan, Jane C.; Waterman, Amy D.; Zavala, Edward Y.; Rodrigue, James R.

2015-01-01

Live donor kidney transplantation is the best treatment option for most patients with late-stage chronic kidney disease; however, the rate of living kidney donation has declined in the United States. A consensus conference was held June 5–6, 2014 to identify best practices and knowledge gaps pertaining to live donor kidney transplantation and living kidney donation. Transplant professionals, patients, and other key stakeholders discussed processes for educating transplant candidates and potential living donors about living kidney donation; efficiencies in the living donor evaluation process; disparities in living donation; and financial and systemic barriers to living donation. We summarize the consensus recommendations for best practices in these educational and clinical domains, future research priorities, and possible public policy initiatives to remove barriers to living kidney donation. PMID:25648884

Safe and ethical living kidney donation in Qatar: A national health system's approach.

PubMed

Asim, Muhammad; Al-Maslamani, Yousuf; Al-Malki, Hassan

2017-01-01

The increasing incidence of end-stage kidney disease in Qatar has led to growing demand for donor kidneys. The deceased donor kidney program has yet to achieve its full potential; hence, living kidney donation has been widely adopted as an appropriate alternative. The reliance on living kidney donors however, raises a number of social, ethical, and legal concerns surrounding informed consent, voluntarism, psychosocial evaluation, perioperative care, and long-term follow-up of living kidney donors. Many of these concerns become heightened in a multicultural, multilingual society within a Gulf country such as Qatar. This article provides an insight into the challenges that living kidney donation poses in a multiethnic society with significant socioeconomic divides. It also discusses the remedial measures that the Qatari government, healthcare authorities, and transplant community have adopted to address these issues.

Safe and ethical living kidney donation in Qatar: A national health system's approach

PubMed Central

Asim, Muhammad; Al-Maslamani, Yousuf; Al-Malki, Hassan

2017-01-01

The increasing incidence of end-stage kidney disease in Qatar has led to growing demand for donor kidneys. The deceased donor kidney program has yet to achieve its full potential; hence, living kidney donation has been widely adopted as an appropriate alternative. The reliance on living kidney donors however, raises a number of social, ethical, and legal concerns surrounding informed consent, voluntarism, psychosocial evaluation, perioperative care, and long-term follow-up of living kidney donors. Many of these concerns become heightened in a multicultural, multilingual society within a Gulf country such as Qatar. This article provides an insight into the challenges that living kidney donation poses in a multiethnic society with significant socioeconomic divides. It also discusses the remedial measures that the Qatari government, healthcare authorities, and transplant community have adopted to address these issues. PMID:28795019

Research on Evaluation of resource allocation efficiency of transportation system based on DEA

NASA Astrophysics Data System (ADS)

Zhang, Zhehui; Du, Linan

2017-06-01

In this paper, we select the time series data onto 1985-2015 years, construct the land (shoreline) resources, capital and labor as inputs. The index system of the output is freight volume and passenger volume, we use Quantitative analysis based on DEA method evaluated the resource allocation efficiency of railway, highway, water transport and civil aviation in China. Research shows that the resource allocation efficiency of various modes of transport has obvious difference, and the impact on scale efficiency is more significant. The most important two ways to optimize the allocation of resources to improve the efficiency of the combination of various modes of transport is promoting the co-ordination of various modes of transport and constructing integrated transportation system.

Optimal water resource allocation modelling in the Lowveld of Zimbabwe

NASA Astrophysics Data System (ADS)

Mhiribidi, Delight; Nobert, Joel; Gumindoga, Webster; Rwasoka, Donald T.

2018-05-01

The management and allocation of water from multi-reservoir systems is complex and thus requires dynamic modelling systems to achieve optimality. A multi-reservoir system in the Southern Lowveld of Zimbabwe is used for irrigation of sugarcane estates that produce sugar for both local and export consumption. The system is burdened with water allocation problems, made worse by decommissioning of dams. Thus the aim of this research was to develop an operating policy model for the Lowveld multi-reservoir system.The Mann Kendall Trend and Wilcoxon Signed-Rank tests were used to assess the variability of historic monthly rainfall and dam inflows for the period 1899-2015. The WEAP model was set up to evaluate the water allocation system of the catchment and come-up with a reference scenario for the 2015/2016 hydrologic year. Stochastic Dynamic Programming approach was used for optimisation of the multi-reservoirs releases.Results showed no significant trend in the rainfall but a significantly decreasing trend in inflows (p < 0.05). The water allocation model (WEAP) showed significant deficits ( ˜ 40 %) in irrigation water allocation in the reference scenario. The optimal rule curves for all the twelve months for each reservoir were obtained and considered to be a proper guideline for solving multi- reservoir management problems within the catchment. The rule curves are effective tools in guiding decision makers in the release of water without emptying the reservoirs but at the same time satisfying the demands based on the inflow, initial storage and end of month storage.

Spot the difference: Operational event sequence diagrams as a formal method for work allocation in the development of single-pilot operations for commercial aircraft.

PubMed

Harris, Don; Stanton, Neville A; Starr, Alison

2015-01-01

Function Allocation methods are important for the appropriate allocation of tasks between humans and automated systems. It is proposed that Operational Event Sequence Diagrams (OESDs) provide a simple yet rigorous basis upon which allocation of work can be assessed. This is illustrated with respect to a design concept for a passenger aircraft flown by just a single pilot where the objective is to replace or supplement functions normally undertaken by the second pilot with advanced automation. A scenario-based analysis (take off) was used in which there would normally be considerable demands and interactions with the second pilot. The OESD analyses indicate those tasks that would be suitable for allocation to automated assistance on the flight deck and those tasks that are now redundant in this new configuration (something that other formal Function Allocation approaches cannot identify). Furthermore, OESDs are demonstrated to be an easy to apply and flexible approach to the allocation of function in prospective systems. OESDs provide a simple yet rigorous basis upon which allocation of work can be assessed. The technique can deal with the flexible, dynamic allocation of work and the deletion of functions no longer required. This is illustrated using a novel design concept for a single-crew commercial aircraft.

Abdominal ultrasound

MedlinePlus

... inflammation in pancreas) Spleen enlargement ( splenomegaly ) Portal hypertension Liver tumors Obstruction of bile ... Digestive system Kidney anatomy Ultrasound in pregnancy Kidney - blood and urine flow ...

Resource Allocation and Budgeting for the 1972-73 Mini-Schools of the Alum Rock Voucher Demonstration. Analysis of the Education Voucher Demonstration. A Working Note.

ERIC Educational Resources Information Center

Haggart, S. A.; Furry, W. S.

This Working Note documents the first year's events and outcomes in developing the budgeting system and resource allocation rules to support the Education Voucher Demonstration. The district now has systems for per pupil resource allocation and school/minischool cost center accounting. The basic voucher of $1,041 for grades 7-8, and $788 for…

Polythelia and associated conditions.

PubMed

Pellegrini, J R; Wagner, R F

1983-09-01

Polythelia (congenital supernumerary nipples) is a marker for more serious anomalies of the urinary and cardiovascular systems. It is associated with obstructive abnormalities of the kidney or the renal collecting system, renal agenesis, renal cell carcinoma, supernumerary kidneys, cardiac conduction disturbances and congenital heart disease.

Control system of the inspection robots group applying auctions and multi-criteria analysis for task allocation

NASA Astrophysics Data System (ADS)

Panfil, Wawrzyniec; Moczulski, Wojciech

2017-10-01

In the paper presented is a control system of a mobile robots group intended for carrying out inspection missions. The main research problem was to define such a control system in order to facilitate a cooperation of the robots resulting in realization of the committed inspection tasks. Many of the well-known control systems use auctions for tasks allocation, where a subject of an auction is a task to be allocated. It seems that in the case of missions characterized by much larger number of tasks than number of robots it will be better if robots (instead of tasks) are subjects of auctions. The second identified problem concerns the one-sided robot-to-task fitness evaluation. Simultaneous assessment of the robot-to-task fitness and task attractiveness for robot should affect positively for the overall effectiveness of the multi-robot system performance. The elaborated system allows to assign tasks to robots using various methods for evaluation of fitness between robots and tasks, and using some tasks allocation methods. There is proposed the method for multi-criteria analysis, which is composed of two assessments, i.e. robot's concurrency position for task among other robots and task's attractiveness for robot among other tasks. Furthermore, there are proposed methods for tasks allocation applying the mentioned multi-criteria analysis method. The verification of both the elaborated system and the proposed tasks' allocation methods was carried out with the help of simulated experiments. The object under test was a group of inspection mobile robots being a virtual counterpart of the real mobile-robot group.

Improving Global Kidney Health: International Society of Nephrology Initiatives and the Global Kidney Health Atlas.

PubMed

Levin, Adeera

2018-01-01

Chronic Kidney Disease (CKD) is a major public health problem and is increasingly being recognized as an important driver of costs in all health care systems. The diversity of outcomes for people living with CKD is in part due to variability in biology, access to care, environmental factors, and health care system differences. The International Society of Nephrology (ISN), working in collaboration with its partners, has evolved into a philanthropic organization, from a traditional medical society, committed to a vision that sees "a future where all people have access to sustainable kidney health". A set of activities, including a Global Kidney Health Summit, the Global Kidney Health Atlas, and a Global Kidney Health Policy Forum, which has formed the basis of a multi-stakeholder engagement process, building on a solid base of ISN programs and educational activities, is described. Through building awareness and increasing capacity to conduct research, the international community will build a more solid foundation on which to advocate for sustainable, ethical solutions to the problem of kidney disease throughout the world. The ISN aims to improve kidney health worldwide through a variety of diverse activities addressing education, advocacy, and research. Collaboration with partners within and outside the medical community is key in achieving this goal. Key Messages: Kidney disease is an important public health problem and is driven by genetic, environmental, and socioeconomic factors. Through active collaboration with diverse partners, the international community is striving for sustainable kidney health and aims to achieve this through coordinated work in a variety of spheres. © 2018 The Author(s) Published by S. Karger AG, Basel.

Dietary vitamin C and E modulates oxidative stress induced-kidney and lens injury in diabetic aged male rats through modulating glucose homeostasis and antioxidant systems.

PubMed

Özkaya, Dilek; Naziroğlu, Mustafa; Armağan, Abdullah; Demirel, Alpay; Köroglu, Banu Kale; Çolakoğlu, Neriman; Kükner, Aysel; Sönmez, Tolga Taha

2011-06-01

Diabetes induces oxidative stress in aged human and rat, although daily supplementation of vitamins C and E (VCE) can be beneficial to aged diabetic rats by reducing free radical production. The aim of the present study was to evaluate whether dietary VCE supplementation relieves oxidative stress in streptozotocin (STZ)-induced diabetic in aged rats. Thirty aged rats were randomly divided into three groups. The first group was used as a control. The second group was made diabetic using a single dose of intraperitoneal STZ. VCE-supplemented feed was given to aged diabetic rats constituting the third group. On the 21st day of the experiment, blood, lens and kidney samples were taken from all animals. Glutathione peroxidase (GSH-Px) activity in lens and kidney, reduced glutathione (GSH), vitamin E and β-carotene concentrations in kidney were lower in the diabetic group than in the control whereas plasma glucose, urea and creatinine, and kidney and lens peroxidation (LP) levels were higher in the diabetic group than in the control. However, kidney and lens LP levels, and plasma glucose, urea and creatinine values were decreased by VCE supplementation. Lens and kidney GSH-Px activity, kidney GSH, vitamin E and β-carotene concentrations and erythrocyte counts were increased by VCE treatment. Kidney weights, vitamin A, haemoglobin, hematocrit, leukocyte and platelets values were not changed by diabetes and/or VCE supplementation. VCE ameliorated also diabetes-induced histopathological changes in kidney. In conclusion, we observed that VCE supplementation is beneficial towards kidney and lens of aged diabetic rats by modulating oxidative and antioxidant systems. Copyright © 2011 John Wiley & Sons, Ltd.

Research on memory management in embedded systems

NASA Astrophysics Data System (ADS)

Huang, Xian-ying; Yang, Wu

2005-12-01

Memory is a scarce resource in embedded system due to cost and size. Thus, applications in embedded systems cannot use memory randomly, such as in desktop applications. However, data and code must be stored into memory for running. The purpose of this paper is to save memory in developing embedded applications and guarantee running under limited memory conditions. Embedded systems often have small memory and are required to run a long time. Thus, a purpose of this study is to construct an allocator that can allocate memory effectively and bear a long-time running situation, reduce memory fragmentation and memory exhaustion. Memory fragmentation and exhaustion are related to the algorithm memory allocated. Static memory allocation cannot produce fragmentation. In this paper it is attempted to find an effective allocation algorithm dynamically, which can reduce memory fragmentation. Data is the critical part that ensures an application can run regularly, which takes up a large amount of memory. The amount of data that can be stored in the same size of memory is relevant with the selected data structure. Skills for designing application data in mobile phone are explained and discussed also.

Automation trust and attention allocation in multitasking workspace.

PubMed

Karpinsky, Nicole D; Chancey, Eric T; Palmer, Dakota B; Yamani, Yusuke

2018-07-01

Previous research suggests that operators with high workload can distrust and then poorly monitor automation, which has been generally inferred from automation dependence behaviors. To test automation monitoring more directly, the current study measured operators' visual attention allocation, workload, and trust toward imperfect automation in a dynamic multitasking environment. Participants concurrently performed a manual tracking task with two levels of difficulty and a system monitoring task assisted by an unreliable signaling system. Eye movement data indicate that operators allocate less visual attention to monitor automation when the tracking task is more difficult. Participants reported reduced levels of trust toward the signaling system when the tracking task demanded more focused visual attention. Analyses revealed that trust mediated the relationship between the load of the tracking task and attention allocation in Experiment 1, an effect that was not replicated in Experiment 2. Results imply a complex process underlying task load, visual attention allocation, and automation trust during multitasking. Automation designers should consider operators' task load in multitasking workspaces to avoid reduced automation monitoring and distrust toward imperfect signaling systems. Copyright © 2018. Published by Elsevier Ltd.

Human kidney proximal tubule cells are vulnerable to the effects of Rauwolfia serpentina.

PubMed

Mossoba, Miriam E; Flynn, Thomas J; Vohra, Sanah; Wiesenfeld, Paddy L; Sprando, Robert L

2015-12-01

Rauwolfia serpentina (or Snake root plant) is a botanical dietary supplement marketed in the USA for maintaining blood pressure. Very few studies have addressed the safety of this herb, despite its wide availability to consumers. Its reported pleiotropic effects underscore the necessity for evaluating its safety. We used a human kidney cell line to investigate the possible negative effects of R. serpentina on the renal system in vitro, with a specific focus on the renal proximal tubules. We evaluated cellular and mitochondrial toxicity, along with a variety of other kidney-specific toxicology biomarkers. We found that R. serpentina was capable of producing highly detrimental effects in our in vitro renal cell system. These results suggest more studies are needed to investigate the safety of this dietary supplement in both kidney and other target organ systems.

Administrative Decision Making and Resource Allocation.

ERIC Educational Resources Information Center

Sardy, Susan; Sardy, Hyman

This paper considers selected aspects of the systems analysis of administrative decisionmaking regarding resource allocations in an educational system. A model of the instructional materials purchase system is presented. The major components of this model are: environment, input, decision process, conversion structure, conversion process, output,…

Who gets the gametes? An argument for a points system for fertility patients

PubMed Central

Jenkins, Simon; Ives, Jonathan; Avery, Sue

2017-01-01

Abstract This paper argues that the convention of allocating donated gametes on a ‘first come, first served’ basis should be replaced with an allocation system that takes into account more morally relevant criteria than waiting time. This conclusion was developed using an empirical bioethics methodology, which involved a study of the views of 18 staff members from seven U.K. fertility clinics, and 20 academics, policy‐makers, representatives of patient groups, and other relevant professionals, on the allocation of donated sperm and eggs. Against these views, we consider some nuanced ways of including criteria in a points allocation system. We argue that such a system is more ethically robust than ‘first come, first served’, but we acknowledge that our results suggest that a points system will meet with resistance from those working in the field. We conclude that criteria such as a patient's age, potentially damaging substance use, and parental status should be used to allocate points and determine which patients receive treatment and in what order. These and other factors should be applied according to how they bear on considerations like child welfare, patient welfare, and the effectiveness of the proposed treatment. PMID:29194680

Allocating capital systemwide. Who gets how much and why.

PubMed

Albertina, R M; Bakewell, T F

1989-05-01

The maturing of multi-institutional healthcare systems has created a need for systemwide approaches to managing investment in capital expenditures. Historically, hospitals have allocated capital using traditional capital budgeting techniques, including discounted cash flow, net present value, and internal rate of return methodologies. Now systems can use a multifactored model to allocate capital among member hospitals. This approach uses historical and projected financial and statistical information to quantify the risks member hospitals face. At the system level, capital allocation decisions should start with the strategic and financial planning processes. Catholic systems face an additional caveat: The system's mission statement drives the planning processes. Conceptually, the capital allocation plan is an attempt to value each hospital as a going, or viable, concern. From this perspective, value is understood as a function of expected return, the certainty of the return, and the return offered by similar investments in other hospital markets. Despite the many determinants of business and financial risk, much of the variance in asset market value can be explained through five assessment criteria: market demographics, position within the market, historical and projected financial performance, historical utilization, and third-party reimbursement mix.

Novel pathologic scoring tools predict end-stage kidney disease in light chain (AL) amyloidosis.

PubMed

Rubinstein, Samuel; Cornell, Robert F; Du, Liping; Concepcion, Beatrice; Goodman, Stacey; Harrell, Shelton; Horst, Sara; Lenihan, Daniel; Slosky, David; Fogo, Agnes; Langone, Anthony

2017-09-01

Light chain (AL) amyloidosis frequently involves the kidney, causing significant morbidity and mortality. A pathologic scoring system with prognostic utility has not been developed. We hypothesized that the extent of amyloid deposition and degree of scarring injury on kidney biopsy, could provide prognostic value, and aimed to develop pathologic scoring tools based on these features. This is a case-control study of 39 patients treated for AL amyloidosis with biopsy-proven kidney involvement at a large academic medical center. Our novel scoring tools, composite scarring injury score (CSIS) and amyloid score (AS) were applied to each kidney biopsy. The primary outcome was progression to dialysis-dependent end-stage kidney disease (ESKD) using a 12-month landmark analysis. At 12 months, nine patients had progressed to ESKD. Patients with an AS ≥7.5 had a significantly higher cumulative incidence of ESKD than those with AS <7.5 (p = .04, 95% CI 0.13-0.64). Using a 12-month landmark analysis, AS correlated with progression to ESKD. These data suggest that a kidney biopsy, in addition to providing diagnostic information, can be the basis for a pathologic scoring system with prognostic significance.

Systemic and kidney toxicity of intraocular administration of vascular endothelial growth factor inhibitors.

PubMed

Pellé, Gaëlle; Shweke, Nasim; Duong Van Huyen, Jean-Paul; Tricot, Leïla; Hessaïne, Sadika; Frémeaux-Bacchi, Véronique; Hiesse, Christian; Delahousse, Michel

2011-05-01

Intravenous injection of angiogenesis-inhibitor drugs is used widely to treat cancers. Associated renal complications primarily involve proteinuria and hypertension, and thrombotic microangiopathies also have been described. Intravitreal anti-vascular endothelial growth factor (VEGF) therapy currently is used by ophthalmologists to treat neovascularization in age-related macular degeneration. However, there is some evidence that intravitreal anti-VEGF injections may result in systemic absorption, with the potential for injury in organs that are reliant on VEGF, such as the kidney. We report the first case to our knowledge of a patient who developed an acute decrease in kidney function, nonimmune microangiopathic hemolytic anemia with schistocytes, and thrombocytopenia after 4 intravitreal injections of ranibizumab. Light microscopy of a kidney biopsy specimen showed segmental duplications of glomerular basement membranes with endothelial swelling and several recanalized arteriolar thrombi. Because of the increasing use of intravitreal anti-VEGF agents, ophthalmologists and nephrologists should be aware of the associated risk of kidney disease. Early detection is crucial so that intravitreal injections can be stopped before severe kidney disease occurs. Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Acute eprosartan-induced intrarenal vasodilation in hypertensive humans is not influenced by dietary sodium intake or angiotensin II co-infusion.

PubMed

van Twist, Daan J L; Houben, Alfons J H M; de Leeuw, Peter W; Kroon, Abraham A

2016-08-01

Angiotensin II (Ang II) is thought to play an important role in the development of hypertension. Nevertheless, knowledge on the angiotensin II type-1-receptors (AT1Rs) in the hypertensive kidney and the influence of sodium intake and renin-angiotensin system activity on intrarenal AT1R blockade is scarce. To improve our understanding of renal AT1Rs in hypertensive patients, we studied the effects of acute, local administration of AT1R-blocker eprosartan in kidneys of patients with essential hypertension (off medication). In 73 hypertensive patients who were scheduled for diagnostic renal angiography, we measured renal blood flow (Xenon washout method) before and during intrarenal infusion of two incremental doses of eprosartan (3 and 10 μg/kg/min for 15 min per dose). We hypothesized that the vasodilatory effects of eprosartan would be enhanced by low sodium intake and would be reduced during Ang II co-infusion. Therefore, we allocated the patients to either a high or a low sodium diet and coinfused Ang II (1 ng/kg/min) in a subgroup. Eprosartan infusion resulted in intrarenal vasodilation in all groups. No differences in the magnitude of this effect were found between the groups. No correlation was found between 24-h urinary sodium excretion (a proxy for dietary sodium intake) and the effect of eprosartan. Eprosartan-induced vasodilation is not influenced by sodium intake and/or co-infusion of Ang II. These rather unexpected findings could be explained by differences between circulating and tissue Ang II levels, variations in AT1R expression, and/or stimulation of other vasodilatory pathways.

Redox system and phospholipid metabolism in the kidney of hypertensive rats after FAAH inhibitor URB597 administration.

PubMed

Biernacki, Michał; Ambrożewicz, Ewa; Gęgotek, Agnieszka; Toczek, Marek; Bielawska, Katarzyna; Skrzydlewska, Elżbieta

2018-05-01

Primary and secondary hypertension is associated with kidney redox imbalance resulting in enhanced reactive oxygen species (ROS) and enzymes dependent phospholipid metabolism. The fatty acid amide hydrolase inhibitor, URB597, modulates the levels of endocannabinoids, particularly of anandamide, which is responsible for controlling blood pressure and regulating redox balance. Therefore, this study aimed to compare the effects of chronic URB597 administration to spontaneously hypertensive rats (SHR) and rats with secondary hypertension (DOCA-salt rats) on the kidney metabolism associated with the redox and endocannabinoid systems. It was shown fatty acid amide hydrolase (FAAH) inhibitor decreased the activity of ROS-generated enzymes what resulted in a reduction of ROS level. Moreover varied changes in antioxidant parameters were observed with tendency to improve antioxidant defense in SHR kidney. Moreover, URB597 administration to hypertensive rats decreased pro-inflammatory response, particularly in the kidneys of DOCA-salt hypertensive rats. URB597 had tendency to enhance ROS-dependent phospholipid oxidation, estimated by changes in neuroprostanes in the kidney of SHR and reactive aldehydes (4-hydroxynonenal and malondialdehyde) in DOCA-salt rats, in particular. The administration of FAAH inhibitor resulted in increased level of endocannabinoids in kidney of both groups of hypertensive rats led to enhanced expression of the cannabinoid receptors type 1 and 2 in SHR as well as vanilloid receptor 1 receptors in DOCA-salt rats. URB597 given to normotensive rats also affected kidney oxidative metabolism, resulting in enhanced level of neuroprostanes in Wistar Kyoto rats and reactive aldehydes in Wistar rats. Moreover, the level of endocannabinoids and cannabinoid receptors were significantly higher in both control groups of rats after URB597 administration. In conclusion, because URB597 disturbed the kidney redox system and phospholipid ROS-dependent and enzymatic-dependent metabolism, the administration of this inhibitor may enhance kidney disorders depending on model of hypertension, but may also cause kidney disturbances in control rats. Therefore, further studies are warranted. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Modulating kidney transplant interstitial fibrosis and tubular atrophy: is the RAAS an important target?

PubMed

Amer, Hatem; Griffin, Matthew D

2014-02-01

In follow-up to a recently published randomized controlled clinical trial, Issa et al. provide evidence that systemic activity and physiological responsiveness of the renin aldosterone angiotensin system (RAAS) are well within normal limits in most kidney recipients during the first 5 years post-transplant. Implications of the results include the need to better understand intra-renal RAAS activity in transplanted kidneys and to identify patients in which the graft-protective effects of RAAS blockade are most relevant.

Costs of task allocation with local feedback: Effects of colony size and extra workers in social insects and other multi-agent systems.

PubMed

Radeva, Tsvetomira; Dornhaus, Anna; Lynch, Nancy; Nagpal, Radhika; Su, Hsin-Hao

2017-12-01

Adaptive collective systems are common in biology and beyond. Typically, such systems require a task allocation algorithm: a mechanism or rule-set by which individuals select particular roles. Here we study the performance of such task allocation mechanisms measured in terms of the time for individuals to allocate to tasks. We ask: (1) Is task allocation fundamentally difficult, and thus costly? (2) Does the performance of task allocation mechanisms depend on the number of individuals? And (3) what other parameters may affect their efficiency? We use techniques from distributed computing theory to develop a model of a social insect colony, where workers have to be allocated to a set of tasks; however, our model is generalizable to other systems. We show, first, that the ability of workers to quickly assess demand for work in tasks they are not currently engaged in crucially affects whether task allocation is quickly achieved or not. This indicates that in social insect tasks such as thermoregulation, where temperature may provide a global and near instantaneous stimulus to measure the need for cooling, for example, it should be easy to match the number of workers to the need for work. In other tasks, such as nest repair, it may be impossible for workers not directly at the work site to know that this task needs more workers. We argue that this affects whether task allocation mechanisms are under strong selection. Second, we show that colony size does not affect task allocation performance under our assumptions. This implies that when effects of colony size are found, they are not inherent in the process of task allocation itself, but due to processes not modeled here, such as higher variation in task demand for smaller colonies, benefits of specialized workers, or constant overhead costs. Third, we show that the ratio of the number of available workers to the workload crucially affects performance. Thus, workers in excess of those needed to complete all tasks improve task allocation performance. This provides a potential explanation for the phenomenon that social insect colonies commonly contain inactive workers: these may be a 'surplus' set of workers that improves colony function by speeding up optimal allocation of workers to tasks. Overall our study shows how limitations at the individual level can affect group level outcomes, and suggests new hypotheses that can be explored empirically.

Costs of task allocation with local feedback: Effects of colony size and extra workers in social insects and other multi-agent systems

PubMed Central

Dornhaus, Anna; Su, Hsin-Hao

2017-01-01

Adaptive collective systems are common in biology and beyond. Typically, such systems require a task allocation algorithm: a mechanism or rule-set by which individuals select particular roles. Here we study the performance of such task allocation mechanisms measured in terms of the time for individuals to allocate to tasks. We ask: (1) Is task allocation fundamentally difficult, and thus costly? (2) Does the performance of task allocation mechanisms depend on the number of individuals? And (3) what other parameters may affect their efficiency? We use techniques from distributed computing theory to develop a model of a social insect colony, where workers have to be allocated to a set of tasks; however, our model is generalizable to other systems. We show, first, that the ability of workers to quickly assess demand for work in tasks they are not currently engaged in crucially affects whether task allocation is quickly achieved or not. This indicates that in social insect tasks such as thermoregulation, where temperature may provide a global and near instantaneous stimulus to measure the need for cooling, for example, it should be easy to match the number of workers to the need for work. In other tasks, such as nest repair, it may be impossible for workers not directly at the work site to know that this task needs more workers. We argue that this affects whether task allocation mechanisms are under strong selection. Second, we show that colony size does not affect task allocation performance under our assumptions. This implies that when effects of colony size are found, they are not inherent in the process of task allocation itself, but due to processes not modeled here, such as higher variation in task demand for smaller colonies, benefits of specialized workers, or constant overhead costs. Third, we show that the ratio of the number of available workers to the workload crucially affects performance. Thus, workers in excess of those needed to complete all tasks improve task allocation performance. This provides a potential explanation for the phenomenon that social insect colonies commonly contain inactive workers: these may be a ‘surplus’ set of workers that improves colony function by speeding up optimal allocation of workers to tasks. Overall our study shows how limitations at the individual level can affect group level outcomes, and suggests new hypotheses that can be explored empirically. PMID:29240763

Perceptions and Attitudes of Health Professionals in Kenya on National Health Care Resource Allocation Mechanisms: A Structural Equation Modeling

PubMed Central

Owili, Patrick Opiyo; Hsu, Yi-Hsin Elsa; Chern, Jin-Yuan; Chiu, Chiung-Hsuan Megan; Wang, Bill; Huang, Kuo-Cherh; Muga, Miriam Adoyo

2015-01-01

Background Health care resource allocation is key towards attaining equity in the health system. However, health professionals’ perceived impact and attitude towards health care resource allocation in Sub-Saharan Africa is unknown; furthermore, they occupy a position which makes them notice the impact of different policies in their health system. This study explored perceptions and attitudes of health professionals in Kenya on health care resource allocation mechanism. Method We conducted a survey of a representative sample of 341 health professionals in Moi Teaching and Referral Hospital from February to April 2012, consisting of over 3000 employees. We assessed health professionals’ perceived impact and attitudes on health care resource allocation mechanism in Kenya. We used structural equation modeling and applied a Confirmatory Factor Analysis using Robust Maximum Likelihood estimation procedure to test the hypothesized model. Results We found that the allocation mechanism was negatively associated with their perceived positive impact (-1.04, p < .001), health professionals’ satisfaction (-0.24, p < .01), and professionals’ attitudes (-1.55, p < .001) while it was positively associated with perceived negative impact (1.14, p < .001). Perceived positive impact of the allocation mechanism was negatively associated with their overall satisfaction (-0.08) and attitude (-0.98) at p < .001, respectively. Furthermore, overall satisfaction was negatively associated with attitude (-1.10, p <.001). On the other hand, perceived negative impact of the allocation was positively associated with overall satisfaction (0.29, p <.001) but was not associated with attitude. Conclusion The result suggests that health care resource allocation mechanism has a negative effect towards perceptions, attitudes and overall satisfaction of health professionals who are at the frontline in health care. These findings can serve as a crucial reference for policymakers as the Kenyan health system move towards devolving the system of governance. PMID:26039053

Effect of Dietary Supplements in Reducing Probability of Death for Uremic Crises in Dogs Affected by Chronic Kidney Disease (Masked RCCT)

PubMed Central

Zatelli, Andrea; Pierantozzi, Marco; D'Ippolito, Paola; Bigliati, Mauro; Zini, Eric

2012-01-01

Chitosan and alkalinizing agents can decrease morbidity and mortality in humans with chronic kidney disease (CKD). Whether this holds true in dog is not known. Objective of the study was to determine whether a commercial dietary supplement containing chitosan, phosphate binders, and alkalinizing agents (Renal), compared to placebo, reduces mortality rate due to uremic crises in dogs with spontaneous CKD, fed a renal diet (RD). A masked RCCT was performed including 31 azotemic dogs with spontaneous CKD. Dogs enrolled in the study were randomly allocated to receive RD plus placebo (group A; 15 dogs) or RD plus Renal (group B; 16 dogs). During a first 4-week period, all dogs were fed an RD and then randomized and clinically evaluated up to 44 weeks. The effects of dietary supplements on mortality rate due to uremic crises were assessed. At 44 weeks, compared to group A, dogs in group B had approximately 50% lower mortality rate due to uremic crises (P = 0.015). Dietary supplementation with chitosan, phosphate binders, and alkalinizing agents, along with an RD, is beneficial in reducing mortality rate in dogs with spontaneous CKD. PMID:22593665

Protective Effect of Morocco Carob Honey Against Lead-Induced Anemia and Hepato-Renal Toxicity.

PubMed

Fihri, Aicha Fassi; Al-Waili, Noori S; El-Haskoury, Redouan; Bakour, Meryem; Amarti, Afaf; Ansari, Mohammad J; Lyoussi, Badiaa

2016-01-01

Natural honey has many biological activities including protective effect against toxic materials. The aim of this study was to evaluate the protective effect of carob honey against lead-induced hepato-renal toxicity and lead-induced anemia in rabbits. Twenty four male rabbits were allocated into four groups six rabbits each; group 1: control group, received distilled water (0.1 ml / kg.b.wt /daily); group 2: received oral lead acetate (2 g/kg.b.wt/daily); group 3: treated with oral honey (1g /kg.b.wt/daily) and oral lead (2 g/kg.b.wt/daily), and group 4: received oral honey (1 g/kg.b.wt/daily). Honey and lead were given daily during 24 days of experimentation. Laboratory tests and histopathological evaluations of kidneys were done. Oral administration of lead induced hepatic and kidney injury and caused anemia during three weeks of the exposure. Treatment with honey prevented hepato-renal lead toxicity and ameliorated lead-induced anemia when honey was given to animals during lead exposure. It might be concluded that honey has a protective effect against lead-induced blood, hepatic and renal toxic effects. © 2016 The Author(s) Published by S. Karger AG, Basel.

Increasing the pool of deceased donor organs for kidney transplantation.

PubMed

Schold, Jesse D; Segev, Dorry L

2012-03-27

Expanding the pool of available deceased donor kidneys is critical for improving the outcomes of prospective and current renal transplant candidates. A number of interventions have been proposed that may increase the pool of donors in the US. However, these interventions have variable levels of empirical evidence supporting their potential beneficial impact. Proposed interventions include the instigation of policies for presumed donor consent, the expansion of donor registration, increased quality oversight of transplant providers, financial incentives for donors, increased reimbursement for higher risk donors, alterations in organ allocation policies and distribution, and the selective use of donors with potential or known risk for disease transmission. Many of these interventions have contentious elements that may have delayed or impeded their implementation; however, these options should be considered in the context of the diminishing prognoses for prospective transplant patients, given the increasing scarcity of donor organs relative to the population need. In this Review, we outline the proposed interventions and briefly discuss salient issues that characterize the debates concerning their implementation and effectiveness. Ultimately, any intervention must be based on the best evidence available, with consideration of numerous stakeholders and in conjunction with a careful evaluation of long-term and potential unintended consequences.

Crossing Anatomic Barriers-Transplantation of a Kidney with 5 Arteries, Duplication of the Pyelocalyceal System, and Double Ureter.

PubMed

Bachul, Piotr J; Osuch, Czesław; Chang, Ea-Sle; Bętkowska-Prokop, Alina; Pasternak, Artur; Szura, Mirosław; Matyja, Andrzej; Walocha, Jerzy A

2017-10-01

During the time of organ harvest, it is crucial for the kidney procurement team to consider significant vascular anatomical variations. Multiple renal arteries are not uncommon, and unintentional injury can result in an irreversibly damaged kidney graft that needs to be discarded. We present a kidney graft with 5 renal arteries and a single vein that was successfully procured and implanted with good graft function at discharge and at 4-yr follow-up. According to the literature, additional renal arteries can be found in about 33% of kidneys. This is the first study on a kidney with 5 arteries in the published literature, especially in the context of transplantation.

Industrial process system assessment: bridging process engineering and life cycle assessment through multiscale modeling.

EPA Science Inventory

The Industrial Process System Assessment (IPSA) methodology is a multiple step allocation approach for connecting information from the production line level up to the facility level and vice versa using a multiscale model of process systems. The allocation procedure assigns inpu...

48 CFR 1631.203-70 - Allocation techniques.

Code of Federal Regulations, 2011 CFR

2011-10-01

... among cost centers at the initial entry into the cost accounting system shall be made in compliance with... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Allocation techniques. 1631.203-70 Section 1631.203-70 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT...

Intra-Abdominal Cooling System Limits Ischemia-Reperfusion Injury During Robot-Assisted Renal Transplantation.

PubMed

Meier, R P H; Piller, V; Hagen, M E; Joliat, C; Buchs, J-B; Nastasi, A; Ruttimann, R; Buchs, N C; Moll, S; Vallée, J-P; Lazeyras, F; Morel, P; Bühler, L

2018-01-01

Robot-assisted kidney transplantation is feasible; however, concerns have been raised about possible increases in warm ischemia times. We describe a novel intra-abdominal cooling system to continuously cool the kidney during the procedure. Porcine kidneys were procured by standard open technique. Groups were as follows: Robotic renal transplantation with (n = 11) and without (n = 6) continuous intra-abdominal cooling and conventional open technique with intermittent 4°C saline cooling (n = 6). Renal cortex temperature, magnetic resonance imaging, and histology were analyzed. Robotic renal transplantation required a longer anastomosis time, either with or without the cooling system, compared to the open approach (70.4 ± 17.7 min and 74.0 ± 21.5 min vs. 48.7 ± 11.2 min, p-values < 0.05). The temperature was lower in the robotic group with cooling system compared to the open approach group (6.5 ± 3.1°C vs. 22.5 ± 6.5°C; p = 0.001) or compared to the robotic group without the cooling system (28.7 ± 3.3°C; p < 0.001). Magnetic resonance imaging parenchymal heterogeneities and histologic ischemia-reperfusion lesions were more severe in the robotic group without cooling than in the cooled (open and robotic) groups. Robot-assisted kidney transplantation prolongs the warm ischemia time of the donor kidney. We developed a novel intra-abdominal cooling system that suppresses the noncontrolled rewarming of donor kidneys during the transplant procedure and prevents ischemia-reperfusion injuries. © 2017 The Authors. American Journal of Transplantation published by Wiley Periodicals, Inc. on behalf of American Society of Transplant Surgeons.

Preliminary feasibility study of a new method of hypothermia in an experimental canine model

PubMed Central

Sert, İbrahim Ünal; Akand, Murat; Kılıç, Özcan; Yavru, Nuri; Bulut, Ersan

2017-01-01

Objective To build up a new microcontroller thermoelectric system to achieve renal hypothermia. Material and methods Renal hypothermia system was tested under in vivo conditions in the kidneys of ten Mongrel dogs. Ambient temperature was evaluated using two different microcontrollers. In order to ensure hypothermia in the renal parenchyma, selection can be made among 4 modules and sensors which detect the temperature of the area. The temperature range of the system was adjusted between −50°C and +50°C. Results When single and double poles of the kidney were cooled, initial mean intraperitoneal temperature values were found 37.7°C for rectum and 36.5°C for renal cortex and medulla. After the temperature of the cooling module was set to 12°C, the module was placed on the poles of the kidney. After fifteen minutes, temperature was 15.4°C in the lower pole of the kidney, 28.1°C in the cortex of the other side and 29.2°C in the intramedullary region. The temperature was found to be 15°C in the vicinity and 26.1°C in the cortex across the module. After the system was stabilized, a very slight change was observed in the temperature. Conclusion Hypothermia system developed ensured desired cooling of the targeted part of the kidney; however, it did not cause a change in the temperature of other parts of the kidney or general body temperature. Thus, it was possible to create a long-term study area for renal parenchymal surgery. PMID:28861307

Preliminary feasibility study of a new method of hypothermia in an experimental canine model.

PubMed

Sert, İbrahim Ünal; Akand, Murat; Kılıç, Özcan; Yavru, Nuri; Bulut, Ersan

2017-09-01

To build up a new microcontroller thermoelectric system to achieve renal hypothermia. Renal hypothermia system was tested under in vivo conditions in the kidneys of ten Mongrel dogs. Ambient temperature was evaluated using two different microcontrollers. In order to ensure hypothermia in the renal parenchyma, selection can be made among 4 modules and sensors which detect the temperature of the area. The temperature range of the system was adjusted between -50°C and +50°C. When single and double poles of the kidney were cooled, initial mean intraperitoneal temperature values were found 37.7°C for rectum and 36.5°C for renal cortex and medulla. After the temperature of the cooling module was set to 12°C, the module was placed on the poles of the kidney. After fifteen minutes, temperature was 15.4°C in the lower pole of the kidney, 28.1°C in the cortex of the other side and 29.2°C in the intramedullary region. The temperature was found to be 15°C in the vicinity and 26.1°C in the cortex across the module. After the system was stabilized, a very slight change was observed in the temperature. Hypothermia system developed ensured desired cooling of the targeted part of the kidney; however, it did not cause a change in the temperature of other parts of the kidney or general body temperature. Thus, it was possible to create a long-term study area for renal parenchymal surgery.

GENERATING SOPHISTICATED SPATIAL SURROGATES USING THE MIMS SPATIAL ALLOCATOR

EPA Science Inventory

The Multimedia Integrated Modeling System (MIMS) Spatial Allocator is open-source software for generating spatial surrogates for emissions modeling, changing the map projection of Shapefiles, and performing other types of spatial allocation that does not require the use of a comm...

Power Allocation and Outage Probability Analysis for SDN-based Radio Access Networks

NASA Astrophysics Data System (ADS)

Zhao, Yongxu; Chen, Yueyun; Mai, Zhiyuan

2018-01-01

In this paper, performance of Access network Architecture based SDN (Software Defined Network) is analyzed with respect to the power allocation issue. A power allocation scheme PSO-PA (Particle Swarm Optimization-power allocation) algorithm is proposed, the proposed scheme is subjected to constant total power with the objective of minimizing system outage probability. The entire access network resource configuration is controlled by the SDN controller, then it sends the optimized power distribution factor to the base station source node (SN) and the relay node (RN). Simulation results show that the proposed scheme reduces the system outage probability at a low complexity.

Optimal Sensor Allocation for Fault Detection and Isolation

NASA Technical Reports Server (NTRS)

Azam, Mohammad; Pattipati, Krishna; Patterson-Hine, Ann

2004-01-01

Automatic fault diagnostic schemes rely on various types of sensors (e.g., temperature, pressure, vibration, etc) to measure the system parameters. Efficacy of a diagnostic scheme is largely dependent on the amount and quality of information available from these sensors. The reliability of sensors, as well as the weight, volume, power, and cost constraints, often makes it impractical to monitor a large number of system parameters. An optimized sensor allocation that maximizes the fault diagnosibility, subject to specified weight, volume, power, and cost constraints is required. Use of optimal sensor allocation strategies during the design phase can ensure better diagnostics at a reduced cost for a system incorporating a high degree of built-in testing. In this paper, we propose an approach that employs multiple fault diagnosis (MFD) and optimization techniques for optimal sensor placement for fault detection and isolation (FDI) in complex systems. Keywords: sensor allocation, multiple fault diagnosis, Lagrangian relaxation, approximate belief revision, multidimensional knapsack problem.

Performance Evaluation Model for Application Layer Firewalls.

PubMed

Xuan, Shichang; Yang, Wu; Dong, Hui; Zhang, Jiangchuan

2016-01-01

Application layer firewalls protect the trusted area network against information security risks. However, firewall performance may affect user experience. Therefore, performance analysis plays a significant role in the evaluation of application layer firewalls. This paper presents an analytic model of the application layer firewall, based on a system analysis to evaluate the capability of the firewall. In order to enable users to improve the performance of the application layer firewall with limited resources, resource allocation was evaluated to obtain the optimal resource allocation scheme in terms of throughput, delay, and packet loss rate. The proposed model employs the Erlangian queuing model to analyze the performance parameters of the system with regard to the three layers (network, transport, and application layers). Then, the analysis results of all the layers are combined to obtain the overall system performance indicators. A discrete event simulation method was used to evaluate the proposed model. Finally, limited service desk resources were allocated to obtain the values of the performance indicators under different resource allocation scenarios in order to determine the optimal allocation scheme. Under limited resource allocation, this scheme enables users to maximize the performance of the application layer firewall.

Integration of ecosystem services into the carbon footprint of milk of South German dairy farms.

PubMed

Robert Kiefer, Lukas; Menzel, Friederike; Bahrs, Enno

2015-04-01

Allocation of greenhouse gas emissions (GHG) in Life Cycle Assessments (LCA) is challenging especially when multi-functionality of dairy farms, which do not only produce milk but also meat is considered. Moreover, some farms fulfill a wide range of additional services for society such as management of renewable natural resources as well as preservation of biodiversity and cultural landscapes. Due to the increasing degradation of ecosystems many industrialized as well as developing countries designed payment systems for environmental services. This study examines different allocation methods of GHG for a comparatively large convenience sample of 113 dairy farms located in grassland-based areas of southern Germany. Results are carbon footprints of 1.99 kg CO2eq/kg of fat and protein corrected milk (FPCM) on average if "no allocation" for coupled products is performed. "Physical allocation" results in 1.53 kg CO2eq/kg FPCM and "conventional economic allocation" in 1.66 kg CO2eq/kg FPCM on average if emissions are apportioned between milk and meat. Economic allocation which includes ecosystem services for society based on the farm net income as a new aspect in this study results in a carbon footprint of 1.5 kg CO2eq/kg FPCM on average. System expansion that puts greater emphasis on coupled beef production accounts for a carbon footprint of 0.68 kg CO2eq/kg FPCM on average. Intense milk production systems with higher milk yields show better results based on "no allocation", "physical allocation" and "conventional economic allocation". By contrast, economic allocation, which takes into account ecosystem services favors extensive systems, especially in less favored areas. This shows that carbon footprints of dairy farms should not be examined one-dimensionally based on the amount of milk and meat that is produced on the farm. Rather, a broader perspective is necessary that takes into account the multi-functionality of dairy farms especially in countries where a wide range of ecosystem services is provided. Copyright © 2015 Elsevier Ltd. All rights reserved.

Economic and financial outcomes in transplantation: whose dime is it anyway?

PubMed

Axelrod, David A

2013-04-01

Organ transplant is a resource-intensive service that has been subjected to increasing scrutiny in this era of cost containment. A detailed understanding of the economic (societal) and financial (transplant provider) implications of organ quality, recipient characteristics, and allocation policy is vital for the transplant professionals. Prior studies of kidney transplant economics demonstrate significant cost savings achieved by eliminating the need for long-term dialysis. However, transplant providers are experiencing higher financial costs because of changes in recipient characteristics and broader use of marginal organs. Liver transplantation economics are also more challenging because of the severity of illness-based organ allocation. Furthermore, the use of more allografts recovered from donors after cardiac death has been demonstrated to increase costs with minimal benefits. Finally, successful long-term mechanical support devices have fundamentally changed the economic implications of advanced heart failure care. Although care for end-stage organ failure through transplant is one of the landmark accomplishments of 20th century medicine, maintaining or expanding access to transplant care is threatened by the high cost of care. Novel strategies are vital to reduce the financial burden faced by the centers that transplant high-risk patients and utilize lower quality organs.

Progression of hypertension and kidney disease in aging fawn-hooded rats is mediated by enhanced influence of renin-angiotensin system and suppression of nitric oxide system and epoxyeicosanoids.

PubMed

Doleželová, Šárka; Jíchová, Šárka; Husková, Zuzana; Vojtíšková, Alžběta; Kujal, Petr; Hošková, Lenka; Kautzner, Josef; Sadowski, Janusz; Červenka, Luděk; Kopkan, Libor

The fawn-hooded hypertensive (FHH) rat serves as a genetic model of spontaneous hypertension associated with glomerular hyperfiltration and proteinuria. However, the knowledge of the natural course of hypertension and kidney disease in FHH rats remains fragmentary and the underlying pathophysiological mechanisms are unclear. In this study, over the animals' lifetime, we followed the survival rate, blood pressure (telemetry), indices of kidney damage, the activity of renin-angiotensin (RAS) and nitric oxide (NO) systems, and CYP450-epoxygenase products (EETs). Compared to normotensive controls, no elevation of plasma and renal RAS was observed in prehypertensive and hypertensive FHH rats; however, RAS inhibition significantly reduced systolic blood pressure (137 ± 9 to 116 ± 8, and 159 ± 8 to 126 ± 4 mmHg, respectively) and proteinuria (62 ± 2 to 37 ± 3, and 132 ± 8 to 87 ± 5 mg/day, respectively). Moreover, pharmacological RAS inhibition reduced angiotensin (ANG) II and increased ANG 1-7 in the kidney and thereby may have delayed the progression of kidney disease. Furthermore, renal NO and EETs declined in the aging FHH rats but not in the control strain. The present results, especially the demonstration of exaggerated vascular responsiveness to ANG II, indicate that RAS may contribute to the development of hypertension and kidney disease in FHH rats. The activity of factors opposing the development of hypertension and protecting the kidney declined with age in this model. Therefore, therapeutic enhancement of this activity besides RAS inhibition could be attempted in the therapy of human hypertension associated with kidney disease.

Inhibition of plasma kallikrein-kinin system to alleviate renal injury and arthritis symptoms in rats with adjuvant-induced arthritis.

PubMed

Zhu, Jie; Wang, Hui; Chen, Jingyu; Wei, Wei

2018-04-01

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Impairment of kidney functions in RA was observed. However, the mechanism of kidney injury of RA has not been clear. Plasma kallikrein-kinin system (KKS) was involved in inflammatory processes in kidney disease. This study aimed to explore the role of plasma KKS in immune reactions and kidney injury of RA. The paw of AA rats appeared to be swelling and redness, the arthritis index was significantly increased on the 18, 21 and 24 d after injection and secondary inflammation in multi-sites was observed. Kidney dysfunction accompanied with inflammatory cell infiltration, tubular epithelial cell mitochondrial swelling and vacuolar degeneration, renal glomerular foot process fusions and glomerular basement membrane thickening were observed in AA rats. The expressions of neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (Kim-1) in kidney of AA rats were increased. In addition, expressions of BK, PK, B1R and B2R in the renal tissue of AA rats were up-regulated. Pro-inflammatory cytokines IL-2, IFN-γ and TNF-α were increased and anti-inflammatory cytokines IL-4 and IL-10 were low in kidney. Plasma kallikrein (PK) inhibitor PKSI-527 attenuated arthritis signs and renal damage, and inhibited BK, PK, B1R and B2R expressions. The protein expressions of P38, p-P38 and p-JNK and IFN-γ and TNF-α were inhibited by PKSI-527. These findings demonstrate that plasma KKS activation contributed to the renal injury of AA rats through MAPK signaling pathway. Plasma KKS might be a potential target for RA therapy.

Stem cells for kidney repair: useful tool for acute renal failure?

PubMed

Yokoo, Takashi; Kawamura, Tetsuya; Kobayashi, Eiji

2008-10-01

Several cell types isolated from adult tissues have been reported to differentiate into mature kidney cells that may participate in renal repair after systemic administration. Chen et al. report that local mesenchymal stem cells derived from adult mouse kidneys are another source of cells with similar properties. Although these cells have the potential to differentiate into endothelial-lineage cell types, their therapeutic benefit to the ischemic kidney is mainly via the production of renoprotective factors.

Financial Planning in Australian Universities. AIR 1996 Annual Forum Paper.

ERIC Educational Resources Information Center

Sharma, Raj; And Others

This paper describes resource allocation in Australian universities including the broader context of national restructuring and a case study of one university's attempt to restructure resource allocation within the university. The 1987 restructuring of the Australian system from a binary system to a unified national system and the associated…

Studying the effect on system preference by varying coproduct allocation in creating life-cycle inventory.

PubMed

Curran, Mary Ann

2007-10-15

How one models the input and output data for a life-cycle assessment (LCA) can greatly affect the results. Although much attention has been paid to allocation methodology by researchers in the field, specific guidance is still lacking: Earlier research focused on the effects of applying various allocation schemes to industrial processes when creating life-cycle inventories. To determine the impact of different allocation approaches upon product choice, this study evaluated the gas- and water-phase emissions during the production, distribution, and use of three hypothetical fuel systems (data that represent conventional gasoline and gasoline with 8.7 and 85% ethanol were used as the basis for modeling). This paper presents an explanation of the allocation issue and the results from testing various allocation schemes (weight, volume, market value, energy, and demand-based) when viewed across the entire system. Impact indicators for global warming, ozone depletion, and human health noncancer (water impact) were lower for the ethanol-containing fuels, while impact indicators for acidification, ecotoxicity, eutrophication, human health criteria, and photochemical smog were lower for conventional gasoline (impacts for the water-related human health cancer category showed mixed results). The relative ranking of conventional gasoline in relation to the ethanol-containing fuels was consistent in all instances, suggesting that, in this case study, the choice of allocation methodology had no impact on indicating which fuel has lower environmental impacts.

Ureteroscopy-assisted Percutaneous Kidney Access Made Easy: First Clinical Experience with a Novel Navigation System Using Electromagnetic Guidance (IDEAL Stage 1).

PubMed

Lima, Estevao; Rodrigues, Pedro L; Mota, Paulo; Carvalho, Nuno; Dias, Emanuel; Correia-Pinto, Jorge; Autorino, Riccardo; Vilaça, João L

2017-10-01

Puncture of the renal collecting system represents a challenging step in percutaneous nephrolithotomy (PCNL). Limitations related to the use of standard fluoroscopic-based and ultrasound-based maneuvers have been recognized. To describe the technique and early clinical outcomes of a novel navigation system for percutaneous kidney access. This was a proof-of-concept study (IDEAL phase 1) conducted at a single academic center. Ten PCNL procedures were performed for patients with kidney stones. Flexible ureterorenoscopy was performed to determine the optimal renal calyx for access. An electromagnetic sensor was inserted through the working channel. Then the selected calyx was punctured with a needle with a sensor on the tip guided by real-time three-dimensional images observed on the monitor. The primary endpoints were the accuracy and clinical applicability of the system in clinical use. Secondary endpoints were the time to successful puncture, the number of attempts for successful puncture, and complications. Ten patients were enrolled in the study. The median age was 47.1 yr (30-63), median body mass index was 22.85kg/m 2 (19-28.3), and median stone size was 2.13cm (1.5-2.5cm). All stones were in the renal pelvis. The Guy's stone score was 1 in nine cases and 2 in one case. All 10 punctures of the collecting system were successfully completed at the first attempt without X-ray exposure. The median time to successful puncture starting from insertion of the needle was 20 s (range 15-35). No complications occurred. We describe the first clinical application of a novel navigation system using real-time electromagnetic sensors for percutaneous kidney access. This new technology overcomes the intrinsic limitations of traditional methods of kidney access, allowing safe, precise, fast, and effective puncture of the renal collecting system. We describe a new technology allowing safe and easy puncture of the kidney without radiation exposure. This could significantly facilitate one of the most challenging steps in percutaneous removal of kidney stones. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All rights reserved.

49 CFR 33.50 - Policy.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 1 2013-10-01 2013-10-01 false Policy. 33.50 Section 33.50 Transportation Office of the Secretary of Transportation TRANSPORTATION PRIORITIES AND ALLOCATION SYSTEM Allocation Actions § 33.50 Policy. (a) It is the policy of the Federal Government that the allocations authority under...

48 CFR 1631.203-70 - Allocation techniques.

Code of Federal Regulations, 2010 CFR

2010-10-01

... shall consistently apply the methods and techniques established to classify direct and indirect costs... meant to be exhaustive, but rather are examples of allocation methods that may be acceptable under... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Allocation techniques. 1631...

Frequency allocations for a new satellite service - Digital audio broadcasting

NASA Technical Reports Server (NTRS)

Reinhart, Edward E.

1992-01-01

The allocation in the range 500-3000 MHz for digital audio broadcasting (DAB) is described in terms of key issues such as the transmission-system architectures. Attention is given to the optimal amount of spectrum for allocation and the technological considerations relevant to downlink bands for satellite and terrestrial transmissions. Proposals for DAB allocations are compared, and reference is made to factors impinging on the provision of ground/satellite feeder links. The allocation proposals describe the implementation of 50-60-MHz bandwidths for broadcasting in the ranges near 800 MHz, below 1525 MHz, near 2350 MHz, and near 2600 MHz. Three specific proposals are examined in terms of characteristics such as service areas, coverage/beam, channels/satellite beam, and FCC license status. Several existing problems are identified including existing services crowded with systems, the need for new bands in the 1000-3000-MHz range, and variations in the nature and intensity of implementations of existing allocations that vary from country to country.

Cytotoxic effect of fenitrothion and lambda-cyhalothrin mixture on lipid peroxidation and antioxidant defense system in rat kidney.

PubMed

El-Demerdash, Fatma M

2012-01-01

A mixture of pyrethroids plus organophosphates was assessed for their potential effects on lipid peroxidation, the antioxidant defense system and lactate dehydrogenase (LDH) in rat kidney in vitro. Various insecticide concentrations were incubated with kidney homogenate at 37°C for different incubation times. Treatment with fenitothion (FNT) plus lambda-cyhalothrin (LC) caused a significant induction (P < 0.05) in thiobarbituric acid reactive substances (TBARS), which might be associated to decreased levels of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST) activities and protein content in rat kidney. However, a significant induction of lactate dehydrogenase (LDH) activity was observed. The effect was concentration and time dependent. It can be concluded that depletion of GSH might indicate that reactive oxygen species (ROS) could be involved in the toxic effects of FNT plus LC which lead to marked perturbations in antioxidant defense system.

Drying Characteristics and Water-soluble Polysaccharides Evaluation of Kidney Shape Ganoderma lucidum Drying in Air Circulation System

NASA Astrophysics Data System (ADS)

Prasetyo, D. J.; Jatmiko, T. H.; Poeloengasih, C. D.; Kismurtono, M.

2017-12-01

In this project, drying kinetic of kidney shape Ganoderma lucidum fruiting body in air circulation system was studied. The drying experiments were conducted at 40, 50 and 60°C with air flow rate of 1.3 ms-1. Samples were weighted periodically until no change in sample weight was recorded, and then the samples were analyzed for its moisture content. Four different thin-layer mathematical models (Newton, Page, Two-term, Midilli) were used and compare to evaluate the drying curves of kidney shape G. lucidum. The water-soluble polysaccharides were evaluated in order to find the best drying temperature condition. The results indicates that Midilli model was the fittest model to describe the characteristic of kidney shape G. lucidum in the air circulation drying system and temperature of 50°C was the best drying condition to get highest value of water-soluble polysaccharides.

Ising game: Nonequilibrium steady states of resource-allocation systems

NASA Astrophysics Data System (ADS)

Xin, C.; Yang, G.; Huang, J. P.

2017-04-01

Resource-allocation systems are ubiquitous in the human society. But how external fields affect the state of such systems remains poorly explored due to the lack of a suitable model. Because the behavior of spins pursuing energy minimization required by physical laws is similar to that of humans chasing payoff maximization studied in game theory, here we combine the Ising model with the market-directed resource-allocation game, yielding an Ising game. Based on the Ising game, we show theoretical, simulative and experimental evidences for a formula, which offers a clear expression of nonequilibrium steady states (NESSs). Interestingly, the formula also reveals a convertible relationship between the external field (exogenous factor) and resource ratio (endogenous factor), and a class of saturation as the external field exceeds certain limits. This work suggests that the Ising game could be a suitable model for studying external-field effects on resource-allocation systems, and it could provide guidance both for seeking more relations between NESSs and equilibrium states and for regulating human systems by choosing NESSs appropriately.

Regional traumatic limb hypothermia attenuates distant hepatic and renal injury following blast limb trauma in rats.

PubMed

Zhao, Hongzhi; Ning, Jiaolin; Duan, Jiaxiang; Gu, Jianteng; Yi, Bin; Lu, Kaizhi; Mo, Liwen; Lai, Xinan; Hennah, Lindsay; Ma, Daqing

2014-09-01

Blast limb injury was reported to result in distant organ injury including the lungs, which can be attenuated with transient regional hypothermia (RH) to the injured limb. We aimed to further study hepatic and renal injuries following blast limb trauma and also to evaluate the protective effects of regional traumatic limb hypothermia on such injuries in rats. Blast limb trauma (BLT) was created using chartaceous electricity detonators in anesthetized male Sprague-Dawley rats. The BLT rats were randomly allocated to undergo regional traumatic limb hypothermic treatment (RH) for 30 minutes, 60 minutes, or 6 hours immediately after the onset of blast or without RH (n = 8 per group). The severity of hepatic and renal injury was assessed through histologic examination and water content (wet/dry weight) in all animals 6 hours later. The level of plasma tumor necrosis factor α (TNF-α), interleukin 6, hydrogen sulfide (H2S), and myeloperoxidase (MPO) together with hepatic and renal MPO, malondialdehyde (MDA), superoxide dismutase, and total antioxidant capacity were measured 6 hours after the blast injury. Following BLT, hepatic injury was evidenced by histopathologic changes, increased water content, as well as plasma alanine aminotransferase and aspartate aminotransferase. Renal histopathologic but not functional changes were also found. RH treatment for all durations attenuated this distant renal injury, but only RH treatment for 60 minutes and 6 hours attenuated distant hepatic injury following BLT. RH treatment for all durations decreased plasma TNF-α and interleukin 6, reduced liver and kidney MPO activity and kidney MDA, and elevated superoxide dismutase and total antioxidant capacity in both liver and kidneys. RH treatment for 60 minutes is the most effective duration to reduce hepatic MPO activity, plasma TNF-α, and kidney MDA. This study indicates that BLT-induced distant renal and hepatic injury could be attenuated by RH treatment through reduction of cytokine release and inhibition of neutrophil accumulation and oxidative stress.

An exploration of mothers' and fathers' views of their identities in chronic-kidney-disease management: parents as students?

PubMed

Swallow, Veronica

2008-12-01

To explore parents' views of their identities as they learn to manage their child's chronic kidney disease. Parents are expected to participate in management and usually learn necessary skills from the multidisciplinary team. Research highlights the importance of professionals defining parents' management roles in chronic disease; but little is known about parents' views on their own identities as the complex and dynamic process of teaching and learning unfolds around their child's condition. According to positioning theory, identity development is a dynamic and fluid process that occurs during interaction, with each person positioning themselves while simultaneously positioning the other person, yet this concept has not been considered in relation to parents' contributions to disease management. A longitudinal, grounded theory study conducted in a UK Children's Kidney Unit. This paper focuses on one aspect of a larger study exploring family learning in disease management. Six mothers and two fathers of six children with a recently diagnosed chronic kidney disease participated in a total of 21 semi-structured interviews during the 18 months after referral to the unit. Interviews included discussion about the parts they played in relation to professionals during the management process. Findings were interpreted within a framework of positioning theory. Parents participated in teaching/learning/assessment that was both planned (involving allocated clinical lessons and tasks) and spontaneous (in response to current situations), to facilitate their participation. They positioned multidisciplinary team members as teachers as well as professionals, simultaneously positioning themselves as students as well as parents. Parents' clinical duties and obligations are not an automatic part of parenting but become part of the broader process of sharing disease management, this can lead to them assuming the additional identity of a 'student'. Involving parents in ongoing discussions about their positions in management may help promote their active and informed participation.

High variation of individual soluble serum CD30 levels of pre-transplantation patients: sCD30 a feasible marker for prediction of kidney allograft rejection?

PubMed

Altermann, Wolfgang; Schlaf, Gerald; Rothhoff, Anita; Seliger, Barbara

2007-10-01

Previous studies have suggested that the pre-transplant levels of the soluble CD30 molecule (sCD30) represent a non-invasive tool which can be used as a biomarker for the prediction of kidney allograft rejections. In order to evaluate the feasibility of sCD30 for pre-transplantation monitoring the sera of potential kidney recipients (n = 652) were collected four times in a 3 months interval. Serum from healthy blood donors (n = 203) served as controls. The sCD30 concentrations of all samples were determined using a commercially available ELISA. This strategy allowed the detection of possible variations of individual sCD30 levels over time. Heterogeneous sCD30 concentrations were found in the samples obtained from individual putative kidney transplant recipients when quarterly measured over 1 year. Total 95% of serum samples obtained from healthy controls exhibited sCD30 values <30 U/ml, whereas most recipients displayed higher serum levels (>30 U/ml). Total 524 patients (80.4%) constantly exhibited serum concentrations of <100 U/ml during the period investigated, whereas 109 patients (16.7%) showed variations by exceeding the proposed 'cut off' of 100 U/ml for one to three times. The frequency of samples exhibiting sCD30 values >100 U/ml was significantly lower than that previously reported. The high degree of variation does not allow the stratification of patients into high and low immunological risk groups based on a single sCD30 value > 100 U/ml. Due to the heterogeneity of sCD30 levels during time course and the high values of SD, its implementation as a pre-transplant marker cannot be justified to generate special provisions for the organ allocation to patients with single sCD30 values > 100 U/ml.

A group-based tasks allocation algorithm for the optimization of long leave opportunities in academic departments

NASA Astrophysics Data System (ADS)

Eyono Obono, S. D.; Basak, Sujit Kumar

2011-12-01

The general formulation of the assignment problem consists in the optimal allocation of a given set of tasks to a workforce. This problem is covered by existing literature for different domains such as distributed databases, distributed systems, transportation, packets radio networks, IT outsourcing, and teaching allocation. This paper presents a new version of the assignment problem for the allocation of academic tasks to staff members in departments with long leave opportunities. It presents the description of a workload allocation scheme and its algorithm, for the allocation of an equitable number of tasks in academic departments where long leaves are necessary.

Access to Heart Transplantation: A Proper Analysis of the Competing Risks of Death and Transplantation Is Required to Optimize Graft Allocation.

PubMed

Cantrelle, Christelle; Legeai, Camille; Latouche, Aurélien; Tuppin, Philippe; Jasseron, Carine; Sebbag, Laurent; Bastien, Olivier; Dorent, Richard

2017-08-01

Heart allocation systems are usually urgency-based, offering grafts to candidates at high risk of waitlist mortality. In the context of a revision of the heart allocation rules, we determined observed predictors of 1-year waitlist mortality in France, considering the competing risk of transplantation, to determine which candidate subgroups are favored or disadvantaged by the current allocation system. Patients registered on the French heart waitlist between 2010 and 2013 were included. Cox cause-specific hazards and Fine and Gray subdistribution hazards were used to determine candidate characteristics associated with waitlist mortality and access to transplantation. Of the 2053 candidates, 7 variables were associated with 1-year waitlist mortality by the Fine and Gray method including 4 candidate characteristics related to heart failure severity (hospitalization at listing, serum natriuretic peptide level, systolic pulmonary artery pressure, and glomerular filtration rate) and 3 characteristics not associated with heart failure severity but with lower access to transplantation (blood type, age, and body mass index). Observed waitlist mortality for candidates on mechanical circulatory support was like that of others. The heart allocation system strongly modifies the risk of pretransplant mortality related to heart failure severity. An in-depth competing risk analysis is therefore a more appropriate method to evaluate graft allocation systems. This knowledge should help to prioritize candidates in the context of a limited donor pool.

Effects of RAAS Inhibitors in Patients with Kidney Disease.

PubMed

Zhang, Fan; Liu, Hong; Liu, Di; Liu, Yexin; Li, Huiqiong; Tan, Xia; Liu, Fuyou; Peng, Youming; Zhang, Hongqing

2017-08-08

Proteinuria and decline of renal function are associated with progression of kidney disease. The Renin Angiotensin Aldosterone System (RAAS) plays an important role in blood pressure regulation, fluid volume, and sodium balance. Overactivity of RAAS contributes to the pathogenesis of a variety of clinical conditions including progress of chronic kidney disease (CKD). This review summarizes the use of RAAS inhibitors as dual therapy or monotherapy in different stages of kidney disease. Experimental and clinical studies have demonstrated RAAS inhibitors prevent proteinuria, kidney fibrosis and slow decline of renal function and thus play a protective role in both early and end stages of kidney disease. While combination use of RAAS inhibitors showed higher efficiency compared with monotherapy, it is also associated with higher incidence of adverse events. Besides ACEI/ARBs, more mechanism research of mineralocorticoid receptor antagonists in kidney disease should be performed.

Kidney black markets and legal transplants: are they opposite sides of the same coin?

PubMed

Mendoza, Roger Lee

2010-03-01

This study investigates why the illegal traffic of kidneys exists and remains resilient in the Philippines. It also evaluates the efficacy of the legal and regulatory framework for kidney (and organ) transplantation, and the corresponding implications for health policy. The experiences of comparable countries are noted. Three surveys were employed in this study: 1) a review of related literature on kidney black markets; 2) questionnaire-based interviews of a multi-stage probability sample of 131 kidney vendors from the two largest supplier regions in the Philippines; and 3) a comparative content analysis of pertinent legal and regulatory measures to address the underground kidney trade. Survey results, based on a 4.0 percent statistical margin of error, indicate that kidney vendors are typically males (98.4 percent) who belong to the lower income classes/groups D and E (88.5 percent). The vast majority of vendors (89.2 percent) were unrelated to kidney recipients, many of whom were of foreign descent (60.3 percent). The study finds that certain key elements underpin the kidney black market in the Philippines: an open, brokered and compensation-based contractual system between unrelated donors and sellers. These elements are sustained and reinforced by a robust supply-and-demand interface anchored on brokerage pricing, government incapacity, policy contradictions and public tolerance or indifference. The study suggests that the relative ambiguity of, and continuity between, the legal and underground kidney transplant systems be carefully addressed prior to enacting more specific reforms. The study also calls attention to the unintended consequences of various reform efforts, which are often neglected in formulating health policy and evaluating its costs and benefits.

The effects of lowering LDL cholesterol with simvastatin plus ezetimibe in patients with chronic kidney disease (Study of Heart and Renal Protection): a randomised placebo-controlled trial.

PubMed

Baigent, Colin; Landray, Martin J; Reith, Christina; Emberson, Jonathan; Wheeler, David C; Tomson, Charles; Wanner, Christoph; Krane, Vera; Cass, Alan; Craig, Jonathan; Neal, Bruce; Jiang, Lixin; Hooi, Lai Seong; Levin, Adeera; Agodoa, Lawrence; Gaziano, Mike; Kasiske, Bertram; Walker, Robert; Massy, Ziad A; Feldt-Rasmussen, Bo; Krairittichai, Udom; Ophascharoensuk, Vuddidhej; Fellström, Bengt; Holdaas, Hallvard; Tesar, Vladimir; Wiecek, Andrzej; Grobbee, Diederick; de Zeeuw, Dick; Grönhagen-Riska, Carola; Dasgupta, Tanaji; Lewis, David; Herrington, William; Mafham, Marion; Majoni, William; Wallendszus, Karl; Grimm, Richard; Pedersen, Terje; Tobert, Jonathan; Armitage, Jane; Baxter, Alex; Bray, Christopher; Chen, Yiping; Chen, Zhengming; Hill, Michael; Knott, Carol; Parish, Sarah; Simpson, David; Sleight, Peter; Young, Alan; Collins, Rory

2011-06-25

Lowering LDL cholesterol with statin regimens reduces the risk of myocardial infarction, ischaemic stroke, and the need for coronary revascularisation in people without kidney disease, but its effects in people with moderate-to-severe kidney disease are uncertain. The SHARP trial aimed to assess the efficacy and safety of the combination of simvastatin plus ezetimibe in such patients. This randomised double-blind trial included 9270 patients with chronic kidney disease (3023 on dialysis and 6247 not) with no known history of myocardial infarction or coronary revascularisation. Patients were randomly assigned to simvastatin 20 mg plus ezetimibe 10 mg daily versus matching placebo. The key prespecified outcome was first major atherosclerotic event (non-fatal myocardial infarction or coronary death, non-haemorrhagic stroke, or any arterial revascularisation procedure). All analyses were by intention to treat. This trial is registered at ClinicalTrials.gov, NCT00125593, and ISRCTN54137607. 4650 patients were assigned to receive simvastatin plus ezetimibe and 4620 to placebo. Allocation to simvastatin plus ezetimibe yielded an average LDL cholesterol difference of 0·85 mmol/L (SE 0·02; with about two-thirds compliance) during a median follow-up of 4·9 years and produced a 17% proportional reduction in major atherosclerotic events (526 [11·3%] simvastatin plus ezetimibe vs 619 [13·4%] placebo; rate ratio [RR] 0·83, 95% CI 0·74-0·94; log-rank p=0·0021). Non-significantly fewer patients allocated to simvastatin plus ezetimibe had a non-fatal myocardial infarction or died from coronary heart disease (213 [4·6%] vs 230 [5·0%]; RR 0·92, 95% CI 0·76-1·11; p=0·37) and there were significant reductions in non-haemorrhagic stroke (131 [2·8%] vs 174 [3·8%]; RR 0·75, 95% CI 0·60-0·94; p=0·01) and arterial revascularisation procedures (284 [6·1%] vs 352 [7·6%]; RR 0·79, 95% CI 0·68-0·93; p=0·0036). After weighting for subgroup-specific reductions in LDL cholesterol, there was no good evidence that the proportional effects on major atherosclerotic events differed from the summary rate ratio in any subgroup examined, and, in particular, they were similar in patients on dialysis and those who were not. The excess risk of myopathy was only two per 10,000 patients per year of treatment with this combination (9 [0·2%] vs 5 [0·1%]). There was no evidence of excess risks of hepatitis (21 [0·5%] vs 18 [0·4%]), gallstones (106 [2·3%] vs 106 [2·3%]), or cancer (438 [9·4%] vs 439 [9·5%], p=0·89) and there was no significant excess of death from any non-vascular cause (668 [14·4%] vs 612 [13·2%], p=0·13). Reduction of LDL cholesterol with simvastatin 20 mg plus ezetimibe 10 mg daily safely reduced the incidence of major atherosclerotic events in a wide range of patients with advanced chronic kidney disease. Merck/Schering-Plough Pharmaceuticals; Australian National Health and Medical Research Council; British Heart Foundation; UK Medical Research Council. Copyright © 2011 Elsevier Ltd. All rights reserved.

Systemic effect of mineral aggregate-based cements: histopathological analysis in rats.

PubMed

Garcia, Lucas da Fonseca Roberti; Huck, Claudia; Magalhães, Fernando Augusto Cintra; Souza, Pedro Paulo Chaves de; Souza Costa, Carlos Alberto de

2017-01-01

Several studies reported the local tissue reaction caused by mineral aggregate-based cements. However, few studies have investigated the systemic effects promoted by these cements on liver and kidney when directly applied to connective tissue. The purpose of this in vivo study was to investigate the systemic effect of mineral aggregate-based cements on the livers and kidneys of rats. Samples of Mineral Trioxide Aggregate (MTA) and a calcium aluminate-based cement (EndoBinder) containing different radiopacifiers were implanted into the dorsum of 40 rats. After 7 and 30 d, samples of subcutaneous, liver and kidney tissues were submitted to histopathological analysis. A score (0-3) was used to grade the inflammatory reaction. Blood samples were collected to evaluate changes in hepatic and renal functions of animals. The moderate inflammatory reaction (2) observed for 7 d in the subcutaneous tissue decreased with time for all cements. The thickness of inflammatory capsules also presented a significant decrease with time (P<.05). Systemically, all cements caused adverse inflammatory reactions in the liver and kidney, being more evident for MTA, persisting until the end of the analysis. Liver functions increased significantly for MTA during 30 d (P<.05). The different cements induced to a locally limited inflammatory reaction. However, from the systemic point of view, the cements promoted significant inflammatory reactions in the liver and kidney. For MTA, the reactions were more accentuated.

Automation Applications in an Advanced Air Traffic Management System : Volume 3. Methodology for Man-Machine Task Allocation

DOT National Transportation Integrated Search

1974-08-01

Volume 3 describes the methodology for man-machine task allocation. It contains a description of man and machine performance capabilities and an explanation of the methodology employed to allocate tasks to human or automated resources. It also presen...

78 FR 19357 - Allocation of Public Transportation Emergency Relief Funds in Response to Hurricane Sandy

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-29

... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Allocation of Public Transportation...) announces the allocation of $2,000,000,000 under the Public Transportation Emergency Relief Program... after an emergency or major disaster that affects public transportation systems. The Appropriations Act...

40 CFR 73.90 - Allowance allocations for small diesel refineries.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Allowance allocations for small diesel... PROGRAMS (CONTINUED) SULFUR DIOXIDE ALLOWANCE SYSTEM Small Diesel Refineries § 73.90 Allowance allocations for small diesel refineries. (a) Initial certification of eligibility. The certifying official of a...

40 CFR 73.90 - Allowance allocations for small diesel refineries.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Allowance allocations for small diesel... PROGRAMS (CONTINUED) SULFUR DIOXIDE ALLOWANCE SYSTEM Small Diesel Refineries § 73.90 Allowance allocations for small diesel refineries. (a) Initial certification of eligibility. The certifying official of a...

48 CFR 3018.109 - Priorities and allocations.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... 3018.109 Section 3018.109 Federal Acquisition Regulations System DEPARTMENT OF HOMELAND SECURITY, HOMELAND SECURITY ACQUISITION REGULATION (HSAR) CONTRACT METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS... as authorized by the Defense Priorities and Allocation System (DPAS). (See (HSAR) 48 CFR 3011.602.) ...

48 CFR 3018.109 - Priorities and allocations.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... 3018.109 Section 3018.109 Federal Acquisition Regulations System DEPARTMENT OF HOMELAND SECURITY, HOMELAND SECURITY ACQUISITION REGULATION (HSAR) CONTRACT METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS... as authorized by the Defense Priorities and Allocation System (DPAS). (See (HSAR) 48 CFR 3011.602.) ...

48 CFR 3018.109 - Priorities and allocations.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... 3018.109 Section 3018.109 Federal Acquisition Regulations System DEPARTMENT OF HOMELAND SECURITY, HOMELAND SECURITY ACQUISITION REGULATION (HSAR) CONTRACT METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS... as authorized by the Defense Priorities and Allocation System (DPAS). (See (HSAR) 48 CFR 3011.602.) ...

Computer architecture for efficient algorithmic executions in real-time systems: New technology for avionics systems and advanced space vehicles

NASA Technical Reports Server (NTRS)

Carroll, Chester C.; Youngblood, John N.; Saha, Aindam

1987-01-01

Improvements and advances in the development of computer architecture now provide innovative technology for the recasting of traditional sequential solutions into high-performance, low-cost, parallel system to increase system performance. Research conducted in development of specialized computer architecture for the algorithmic execution of an avionics system, guidance and control problem in real time is described. A comprehensive treatment of both the hardware and software structures of a customized computer which performs real-time computation of guidance commands with updated estimates of target motion and time-to-go is presented. An optimal, real-time allocation algorithm was developed which maps the algorithmic tasks onto the processing elements. This allocation is based on the critical path analysis. The final stage is the design and development of the hardware structures suitable for the efficient execution of the allocated task graph. The processing element is designed for rapid execution of the allocated tasks. Fault tolerance is a key feature of the overall architecture. Parallel numerical integration techniques, tasks definitions, and allocation algorithms are discussed. The parallel implementation is analytically verified and the experimental results are presented. The design of the data-driven computer architecture, customized for the execution of the particular algorithm, is discussed.

Computer architecture for efficient algorithmic executions in real-time systems: new technology for avionics systems and advanced space vehicles

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

Carroll, C.C.; Youngblood, J.N.; Saha, A.

1987-12-01

Improvements and advances in the development of computer architecture now provide innovative technology for the recasting of traditional sequential solutions into high-performance, low-cost, parallel system to increase system performance. Research conducted in development of specialized computer architecture for the algorithmic execution of an avionics system, guidance and control problem in real time is described. A comprehensive treatment of both the hardware and software structures of a customized computer which performs real-time computation of guidance commands with updated estimates of target motion and time-to-go is presented. An optimal, real-time allocation algorithm was developed which maps the algorithmic tasks onto the processingmore » elements. This allocation is based on the critical path analysis. The final stage is the design and development of the hardware structures suitable for the efficient execution of the allocated task graph. The processing element is designed for rapid execution of the allocated tasks. Fault tolerance is a key feature of the overall architecture. Parallel numerical integration techniques, tasks definitions, and allocation algorithms are discussed. The parallel implementation is analytically verified and the experimental results are presented. The design of the data-driven computer architecture, customized for the execution of the particular algorithm, is discussed.« less

Anatomy of the collecting system of lower pole of the kidney in patients with a single renal stone: a comparative study with individuals with normal kidneys.

PubMed

Zomorrodi, Afshar; Buhluli, Abulfazel; Fathi, Samad

2010-07-01

At least 5% of women and 12% of men during their lives will experience renal colic, at least once. Many theories have been suggested for the etiology of renal stones and variations in the anatomy of the collecting system have been suggested to have a role in stone formation. This study was conducted to examine the role of variation of lower pole collecting system in patients with lower pole kidney stone and compared the same in normal persons (kidney donors). Investigation for the anatomy of the lower pole of the kidney (angle between lower infundibulum and pelvis, length and diameter of the infundibulum and number and pattern distribution of calyces) was carried out using intravenous pyelogram (IVP) in 100 cases with urinary stone (study cases) and 400 persons with normal kidneys (control subjects). The study was a retrospective cross-sectional case control study. Results were analyzed by Mann-Whitney and independent sample chi square tests. The mean infundibulum-pelvic angle (IPA) in control subjects and in patients was 112.5 +/- 10.7 and 96.6 +/- 28.8, respectively. There was significant correlation between reduced angle and stone formation (P= < 0.001). The mean infundibulum-uretero-pelvic angle (IUPA) in control subjects and study cases was 53.5 +/- 12.7 and 42.6 +/- 13.4, respectively. There was significant correlation between decreased angle and stone formation (P = or < 0.001). The mean length of infundibulum of lower pole of kidney (IPIL) in controls and study patients was 22.5 +/- 4.1 and 27.5 +/- 7.7, respectively, which was statistically significant (P< 0.001). The mean number of calyces in lower pole of the kidney (LPCN) in controls and study patients was 2.6 +/- 0.6 and 3 +/- 0.9, respectively, which was statistically significant (P = or < 0.002). There was no significant correlation between distribution of calyces and stone formation (P= 0.366). Our study suggests that abnormal renal anatomy was more common in patients with lower pole kidney stone and should be considered a risk factor for forming lower pole kidney stone.

Neural Network Based Modeling and Analysis of LP Control Surface Allocation

NASA Technical Reports Server (NTRS)

Langari, Reza; Krishnakumar, Kalmanje; Gundy-Burlet, Karen

2003-01-01

This paper presents an approach to interpretive modeling of LP based control allocation in intelligent flight control. The emphasis is placed on a nonlinear interpretation of the LP allocation process as a static map to support analytical study of the resulting closed loop system, albeit in approximate form. The approach makes use of a bi-layer neural network to capture the essential functioning of the LP allocation process. It is further shown via Lyapunov based analysis that under certain relatively mild conditions the resulting closed loop system is stable. Some preliminary conclusions from a study at Ames are stated and directions for further research are given at the conclusion of the paper.

Posterior approach to kidney dissection: An old surgical approach for integrated medical curricula.

PubMed

Daly, Frank J; Bolender, David L; Jain, Deepali; Uyeda, Sheryl; Hoagland, Todd M

2015-01-01

Integrated medical curricular changes are altering the historical regional anatomy approach to abdominal dissection. The renal system is linked physiologically and biochemically to the cardiovascular and respiratory systems; yet, anatomists often approach the urinary system as part of the abdomen and pelvic regions. As part of an integrated curriculum, the renal system must be covered relatively quickly after the thorax in the cadaver laboratory, often without the opportunity to fully appreciate the rest of the abdominal contents. This article provides dissection instructions that follow one of the historical surgical approaches for nephrectomy, including preservation of the posterior abdominal wall neurovasclature. Dissection procedures were developed for first-year medical students, intending this posterior approach to the kidneys to be their first introduction to the renal system. It has been successfully implemented with the first-year medical students at the University of New England, College of Osteopathic Medicine. Utilizing this posterior approach to the kidney enabled the study of the anatomy of the kidneys, suprarenal glands, and renal vessels, as well as the muscles of the lumbar spine, while maintaining the integrity of the anterior abdominal wall and peritoneal cavity for future gastrointestinal and reproductive system-based dissections. © 2015 American Association of Anatomists.

Local therapeutic efficacy with reduced systemic side effects by rapamycin-loaded subcapsular microspheres.

PubMed

Falke, Lucas L; van Vuuren, Stefan H; Kazazi-Hyseni, Filis; Ramazani, Farshad; Nguyen, Tri Q; Veldhuis, Gert J; Maarseveen, Erik M; Zandstra, Jurjen; Zuidema, Johan; Duque, Luisa F; Steendam, Rob; Popa, Eliane R; Kok, Robbert Jan; Goldschmeding, Roel

2015-02-01

Kidney injury triggers fibrosis, the final common pathway of chronic kidney disease (CKD). The increase of CKD prevalence worldwide urgently calls for new therapies. Available systemic treatment such as rapamycin are associated with serious side effects. To study the potential of local antifibrotic therapy, we administered rapamycin-loaded microspheres under the kidney capsule of ureter-obstructed rats and assessed the local antifibrotic effects and systemic side effects of rapamycin. After 7 days, microsphere depots were easily identifiable under the kidney capsule. Both systemic and local rapamycin treatment reduced intrarenal mTOR activity, myofibroblast accumulation, expression of fibrotic genes, and T-lymphocyte infiltration. Upon local treatment, inhibition of mTOR activity and reduction of myofibroblast accumulation were limited to the immediate vicinity of the subcapsular pocket, while reduction of T-cell infiltration was widespread. In contrast to systemically administered rapamycin, local treatment did not induce off target effects such as weight loss. Thus subcapsular delivery of rapamycin-loaded microspheres successfully inhibited local fibrotic response in UUO with less systemic effects. Therapeutic effect of released rapamycin was most prominent in close vicinity to the implanted microspheres. Copyright © 2014 Elsevier Ltd. All rights reserved.

10 CFR 217.2 - Priorities and allocations authority.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Priorities and allocations authority. 217.2 Section 217.2 Energy DEPARTMENT OF ENERGY OIL ENERGY PRIORITIES AND ALLOCATIONS SYSTEM General § 217.2 Priorities and... Security with respect to essential civilian needs supporting national defense, including civil defense and...

LOTUS 1-2-3 and Decision Support: Allocating the Monograph Budget.

ERIC Educational Resources Information Center

Perry-Holmes, Claudia

1985-01-01

Describes the use of electronic spreadsheet software for library decision support systems using personal computers. Discussion covers templates, formulas for allocating the materials budget, LOTUS 1-2-3 and budget allocations, choosing a formula, the spreadsheet itself, graphing capabilities, and advantages and disadvantages of templates. Six…

17 CFR 256.01-11 - Methods of allocation.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) UNIFORM SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 General Instructions § 256.01-11 Methods of allocation. Indirect costs and compensation for use of capital shall be allocated to work orders in accordance with the service company's...

10 CFR 217.2 - Priorities and allocations authority.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Priorities and allocations authority. 217.2 Section 217.2 Energy DEPARTMENT OF ENERGY OIL ENERGY PRIORITIES AND ALLOCATIONS SYSTEM General § 217.2 Priorities and... Security with respect to essential civilian needs supporting national defense, including civil defense and...

Recreation use allocation: Alternative approaches for the Bob Marshall Wilderness Complex

Treesearch

Suzanne Cable; Alan E. Watson

1998-01-01

The allocation of recreation use is a task that has challenged wilderness managers throughout the National Wilderness Preservation System for nearly two decades. This note reviews and evaluates approaches for allocating wilderness recreation use between commercially outfitted, institutionally outfitted, and nonoutfitted visitors to wildlands. Of the 17 identified...

What Does it Really Cost? Allocating Indirect Costs.

ERIC Educational Resources Information Center

Snyder, Herbert; Davenport, Elisabeth

1997-01-01

Better managerial control in terms of decision making and understanding the costs of a system/service result from allocating indirect costs. Allocation requires a three-step process: selecting cost objectives, pooling related overhead costs, and selecting costs bases to connect the objectives to the pooled costs. Argues that activity-based costing…

A review of alternative approaches to healthcare resource allocation.

PubMed

Petrou, S; Wolstenholme, J

2000-07-01

The resources available for healthcare are limited compared with demand, if not need, and all healthcare systems, regardless of their financing and organisation, employ mechanisms to ration or prioritise finite healthcare resources. This paper reviews alternative approaches that can be used to allocate healthcare resources. It discusses the problems encountered when allocating healthcare resources according to free market principles. It then proceeds to discuss the advantages and disadvantages of alternative resource allocation approaches that can be applied to public health systems. These include: (i) approaches based on the concept of meeting the needs of the population to maximising its capacity to benefit from interventions; (ii) economic approaches that identify the most efficient allocation of resources with the view of maximising health benefits or other measures of social welfare; (iii) approaches that seek to ration healthcare by age; and (iv) approaches that resolve resource allocation disputes through debate and bargaining. At present, there appears to be no consensus about the relative importance of the potentially conflicting principles that can be used to guide resource allocation decisions. It is concluded that whatever shape tomorrow's health service takes, the requirement to make equitable and efficient use of finite healthcare resources will remain.

Assessing system reliability and allocating resources: a bayesian approach that integrates multi-level data

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

Graves, Todd L; Hamada, Michael S

2008-01-01

Good estimates of the reliability of a system make use of test data and expert knowledge at all available levels. Furthermore, by integrating all these information sources, one can determine how best to allocate scarce testing resources to reduce uncertainty. Both of these goals are facilitated by modern Bayesian computational methods. We apply these tools to examples that were previously solvable only through the use of ingenious approximations, and use genetic algorithms to guide resource allocation.

Renal hemodynamics and renin-angiotensin system activity in humans with multifocal renal artery fibromuscular dysplasia.

PubMed

van Twist, Daan J L; Houben, Alphons J H M; de Haan, Michiel W; de Leeuw, Peter W; Kroon, Abraham A

2016-06-01

Fibromuscular dysplasia (FMD) is the second most common cause of renovascular hypertension. Nonetheless, knowledge on the renal microvasculature and renin-angiotensin system (RAS) activity in kidneys with FMD is scarce. Given the fairly good results of revascularization, we hypothesized that the renal microvasculature and RAS are relatively spared in kidneys with FMD. In 58 hypertensive patients with multifocal renal artery FMD (off medication) and 116 matched controls with essential hypertension, we measured renal blood flow (Xenon washout method) per kidney and drew blood samples from the aorta and both renal veins to determine renin secretion and glomerular filtration rate per kidney. We found that renal blood flow and glomerular filtration rate in FMD were comparable to those in controls. Although systemic renin levels were somewhat higher in FMD, renal renin secretion was not elevated. Moreover, in patients with unilateral FMD, no differences between the affected and unaffected kidney were observed with regard to renal blood flow, glomerular filtration rate, or renin secretion. In men, renin levels and renin secretion were higher as compared with women. The renal blood flow response to RAS modulation (by intrarenal infusion of angiotensin II, angiotensin-(1-7), an angiotensin II type 1 receptor blocker, or a nitric oxide synthase blocker) was also comparable between FMD and controls. Renal blood flow, glomerular filtration, and the response to vasoactive substances in kidneys with multifocal FMD are comparable to patients with essential hypertension, suggesting that microvascular function is relatively spared. Renin secretion was not increased and the response to RAS modulation was not affected in kidneys with FMD.

48 CFR 8.705-3 - Allocation process.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Allocation process. 8.705-3 Section 8.705-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition From Nonprofit Agencies Employing People Who...

A Protocol for Generating and Exchanging (Genome-Scale) Metabolic Resource Allocation Models.

PubMed

Reimers, Alexandra-M; Lindhorst, Henning; Waldherr, Steffen

2017-09-06

In this article, we present a protocol for generating a complete (genome-scale) metabolic resource allocation model, as well as a proposal for how to represent such models in the systems biology markup language (SBML). Such models are used to investigate enzyme levels and achievable growth rates in large-scale metabolic networks. Although the idea of metabolic resource allocation studies has been present in the field of systems biology for some years, no guidelines for generating such a model have been published up to now. This paper presents step-by-step instructions for building a (dynamic) resource allocation model, starting with prerequisites such as a genome-scale metabolic reconstruction, through building protein and noncatalytic biomass synthesis reactions and assigning turnover rates for each reaction. In addition, we explain how one can use SBML level 3 in combination with the flux balance constraints and our resource allocation modeling annotation to represent such models.

Health Resources Priority and Allocations System (HRPAS). Interim final rule.

PubMed

2015-07-17

This interim final rule establishes standards and procedures by which the U.S. Department of Health and Human Services (HHS) may require that certain contracts or orders that promote the national defense be given priority over other contracts or orders. This rule also sets new standards and procedures by which HHS may allocate materials, services, and facilities to promote the national defense. This rule will implement HHS's administration of priorities and allocations actions, and establish the Health Resources Priorities and Allocation System (HRPAS). The HRPAS will cover health resources pursuant to the authority under Section 101(c) of the Defense Production Act as delegated to HHS by Executive Order 13603. Priorities authorities (and other authorities delegated to the Secretary in E.O. 13603, but not covered by this regulation) may be re-delegated by the Secretary. The Secretary retains the authority for allocations.

Control allocation for gimballed/fixed thrusters

NASA Astrophysics Data System (ADS)

Servidia, Pablo A.

2010-02-01

Some overactuated control systems use a control distribution law between the controller and the set of actuators, usually called control allocator. Beyond the control allocator, the configuration of actuators may be designed to be able to operate after a single point of failure, for system optimization and/or decentralization objectives. For some type of actuators, a control allocation is used even without redundancy, being a good example the design and operation of thruster configurations. In fact, as the thruster mass flow direction and magnitude only can be changed under certain limits, this must be considered in the feedback implementation. In this work, the thruster configuration design is considered in the fixed (F), single-gimbal (SG) and double-gimbal (DG) thruster cases. The minimum number of thrusters for each case is obtained and for the resulting configurations a specific control allocation is proposed using a nonlinear programming algorithm, under nominal and single-point of failure conditions.

Hypertension in pediatric patients with chronic kidney disease: management challenges.

PubMed

Gallibois, Claire M; Jawa, Natasha A; Noone, Damien G

2017-01-01

In contrast to adults where hypertension is a leading cause of chronic kidney disease, in pediatrics, hypertension is predominantly a sequela, however, an important one that, like in adults, is likely associated with a more rapid decline in kidney function or progression of chronic kidney disease to end stage. There is a significant issue with unrecognized, or masked, hypertension in childhood chronic kidney disease. Recent evidence and, therefore, guidelines now suggest targeting a blood pressure of <50th percentile for age, sex, and height in children with proteinuria and chronic kidney disease. This often cannot be achieved by monotherapy and additional agents need to be added. Blockade of the renin angiotensin aldosterone system represents the mainstay of therapy, although often limited by the side effect of hyperkalemia. The addition of a diuretic, at least in the earlier stages of chronic kidney disease, might help mitigate this problem.

Kidney Disease in Oman: a View of the Current and Future Landscapes.

PubMed

Al Alawi, Intisar Hamed; Al Salmi, Issa; Al Mawali, Adhra; Sayer, John A

2017-07-01

Oman is located in the southeast of Arabian Peninsula with a relatively young population of about 3 831 553 people. The Ministry of Health, which is the healthcare provider, is facing a challenge with the increased levels of noncommunicable diseases including chronic kidney disease. A growing number of patients progress to end-stage kidney disease (ESKD), demanding renal replacement therapy. In 2014, there were 1339 of ESKD patients receiving dialysis and almost 1400 patients received kidney transplants. The estimated annual incidence of ESKD is 120 patients per million population. Diabetes mellitus and hypertensive nephropathy are the commonly identified causes of ESKD. Many patients with glomerulonephritis, systemic lupus erythematosus, nephrolithiasis, and inherited kidney disease present with advanced chronic kidney disease. This article reviews the current status of kidney disease in Oman and addresses the present and future needs, through a systematic-review of all related papers.

Cardio-renal syndromes: a systematic approach for consensus definition and classification.

PubMed

Ronco, Claudio; Ronco, Federico

2012-03-01

The "Cardio-Renal Syndrome" (CRS) is a disorder of the heart and kidneys whereby acute or chronic dysfunction in one organ may induce acute or chronic dysfunction of the other. The general definition has been expanded to five subtypes reflecting the primacy of organ dysfunction and the time-frame of the syndrome: CRS type I: acute worsening of heart function (AHF-ACS) leading to kidney injury and/or dysfunction. CRS type II: chronic abnormalities in heart function (CHF-CHD) leading to kidney injury or dysfunction. CRS type III: acute worsening of kidney function (AKI) leading to heart injury and/or dysfunction. CRS type IV: chronic kidney disease (CKD) leading to heart injury, disease and/or dysfunction. CRS type V: systemic conditions leading to simultaneous injury and/or dysfunction of heart and kidney. Different pathophysiological mechanisms are involved in the combined dysfunction of heart and kidney in these five types of the syndrome.

Multimedia transmission in MC-CDMA using adaptive subcarrier power allocation and CFO compensation

NASA Astrophysics Data System (ADS)

Chitra, S.; Kumaratharan, N.

2018-02-01

Multicarrier code division multiple access (MC-CDMA) system is one of the most effective techniques in fourth-generation (4G) wireless technology, due to its high data rate, high spectral efficiency and resistance to multipath fading. However, MC-CDMA systems are greatly deteriorated by carrier frequency offset (CFO) which is due to Doppler shift and oscillator instabilities. It leads to loss of orthogonality among the subcarriers and causes intercarrier interference (ICI). Water filling algorithm (WFA) is an efficient resource allocation algorithm to solve the power utilisation problems among the subcarriers in time-dispersive channels. The conventional WFA fails to consider the effect of CFO. To perform subcarrier power allocation with reduced CFO and to improve the capacity of MC-CDMA system, residual CFO compensated adaptive subcarrier power allocation algorithm is proposed in this paper. The proposed technique allocates power only to subcarriers with high channel to noise power ratio. The performance of the proposed method is evaluated using random binary data and image as source inputs. Simulation results depict that the bit error rate performance and ICI reduction capability of the proposed modified WFA offered superior performance in both power allocation and image compression for high-quality multimedia transmission in the presence of CFO and imperfect channel state information conditions.

Cross-layer Joint Relay Selection and Power Allocation Scheme for Cooperative Relaying System

NASA Astrophysics Data System (ADS)

Zhi, Hui; He, Mengmeng; Wang, Feiyue; Huang, Ziju

2018-03-01

A novel cross-layer joint relay selection and power allocation (CL-JRSPA) scheme over physical layer and data-link layer is proposed for cooperative relaying system in this paper. Our goal is finding the optimal relay selection and power allocation scheme to maximize system achievable rate when satisfying total transmit power constraint in physical layer and statistical delay quality-of-service (QoS) demand in data-link layer. Using the concept of effective capacity (EC), our goal can be formulated into an optimal joint relay selection and power allocation (JRSPA) problem to maximize the EC when satisfying total transmit power limitation. We first solving optimal power allocation (PA) problem with Lagrange multiplier approach, and then solving optimal relay selection (RS) problem. Simulation results demonstrate that CL-JRSPA scheme gets larger EC than other schemes when satisfying delay QoS demand. In addition, the proposed CL-JRSPA scheme achieves the maximal EC when relay located approximately halfway between source and destination, and EC becomes smaller when the QoS exponent becomes larger.

Continuous Real-time Viability Assessment of Kidneys Based on Oxygen Consumption

PubMed Central

Weegman, B.P.; Kirchner, V.A.; Scott, W.E.; Avgoustiniatos, E.S.; Suszynski, T.M.; Ferrer-Fabrega, J.; Rizzari, M.D.; Kidder, L.S.; Kandaswamy, R.; Sutherland, D.E.R.; Papas, K.K.

2010-01-01

Background Current ex vivo quality assessment of donor kidneys is limited to vascular resistance measurements and histological analysis. New techniques for the assessment of organ quality before transplantation may further improve clinical outcomes while expanding the depleted deceased-donor pool. We propose the measurement of whole organ oxygen consumption rate (WOOCR) as a method to assess the quality of kidneys in real time before transplantation. Methods Five porcine kidneys were procured using a donation after cardiac death (DCD) model. The renal artery and renal vein were cannulated and the kidney connected to a custom-made hypothermic machine perfusion (HMP) system equipped with an inline oxygenator and fiber-optic oxygen sensors. Kidneys were perfused at 8°C, and the perfusion parameters and partial oxygen pressures (pO2) were measured to calculate WOOCR. Results Without an inline oxygenator, the pO2 of the perfusion solution at the arterial inlet and venous outlet diminished to near 0 within minutes. However, once adequate oxygenation was provided, a significant pO2 difference was observed and used to calculate the WOOCR. The WOOCR was consistently measured from presumably healthy kidneys, and results suggest that it can be used to differentiate between healthy and purposely damaged organs. Conclusions Custom-made HMP systems equipped with an oxygenator and inline oxygen sensors can be applied for WOOCR measurements. We suggest that WOOCR is a promising approach for the real-time quality assessment of kidneys and other organs during preservation before transplantation. PMID:20692397

Microbubbles induce renal hemorrhage when exposed to diagnostic ultrasound in anesthetized rats.

PubMed

Wible, James H; Galen, Karen P; Wojdyla, Jolette K; Hughes, Michael S; Klibanov, Alexander L; Brandenburger, Gary H

2002-01-01

The generation of ultrasound (US) bioeffects using a clinical imaging system is controversial. We tested the hypothesis that the presence of microbubbles in the US field of a medical imager induces biologic effects. Both kidneys of anesthetized rats were insonified for 5 min using a medical imaging system after the administration of microbubbles. One kidney was insonified using a continuous mode (30 Hz) and the opposite kidney was insonified using an intermittent (1 Hz) technique. The microbubbles were exposed to three different transducer frequencies and four transducer output powers. After insonification, the animals were euthanized, the kidneys were removed and their gross appearance scored under "blinded" conditions using a defined scale. After the administration of microbubbles, US imaging of the kidney caused hemorrhage in the renal tissue. The severity and area of hemorrhage increased with an increase in the transducer power and a decrease in the transducer frequency. Intermittent insonification in the presence of microbubbles produced a greater degree of renal hemorrhage than continuous imaging techniques.

Present and Future in the Treatment of Diabetic Kidney Disease

PubMed Central

de Arriba, Gabriel

2015-01-01

Diabetic kidney disease is the leading cause of end-stage renal disease. Albuminuria is recognized as the most important prognostic factor for chronic kidney disease progression. For this reason, blockade of renin-angiotensin system remains the main recommended strategy, with either angiotensin converting enzyme inhibitors or angiotensin II receptor blockers. However, other antiproteinuric treatments have begun to be studied, such as direct renin inhibitors or aldosterone blockers. Beyond antiproteinuric treatments, other drugs such as pentoxifylline or bardoxolone have yielded conflicting results. Finally, alternative pathogenic pathways are being explored, and emerging therapies including antifibrotic agents, endothelin receptor antagonists, or transcription factors show promising results. The aim of this review is to explain the advances in newer agents to treat diabetic kidney disease, along with the background of the renin-angiotensin system blockade. PMID:25945357

Dual renin-angiotensin-aldosterone system blockade for diabetic kidney disease.

PubMed

Pichler, Raimund H; de Boer, Ian H

2010-08-01

Blockade of the renin-angiotensin-aldosterone system (RAAS) prevents the development and progression of diabetic kidney disease (DKD). It is controversial whether the simultaneous use of two RAAS inhibitors (ie, dual RAAS blockade) further improves renal outcomes. This review examines the scientific rationale and current clinical evidence addressing the use of dual RAAS blockade to prevent and treat DKD. It is concluded that dual RAAS blockade should not be routinely applied to patients with low or moderate risk of progressive kidney disease (normoalbuminuria or microalbuminuria with preserved glomerular filtration rate). For patients with high risk of progressive kidney disease (substantial albuminuria or impaired glomerular filtration rate), clinicians should carefully weigh the potential risks and benefits of dual RAAS blockade on an individual basis until ongoing clinical trials provide further insight.

Close pathological correlations between chronic kidney disease and reproductive organ-associated abnormalities in female cotton rats.

PubMed

Ichii, Osamu; Nakamura, Teppei; Irie, Takao; Kouguchi, Hirokazu; Sotozaki, Kozue; Horino, Taro; Sunden, Yuji; Elewa, Yaser Hosny Ali; Kon, Yasuhiro

2018-03-01

Cotton rat ( Sigmodon hispidus) is a useful experimental rodent for the study of human infectious diseases. We previously clarified that cotton rats, particularly females, developed chronic kidney disease characterized by cystic lesions, inflammation, and fibrosis. The present study investigated female-associated factors for chronic kidney disease development in cotton rats. Notably, female cotton rats developed separation of the pelvic symphysis and hypertrophy in the vaginal parts of the cervix with age, which strongly associated with pyometra. The development of pyometra closely associated with the deterioration of renal dysfunction or immunological abnormalities was indicated by blood urea nitrogen and serum creatinine or spleen weight and serum albumin/globulin ratio, respectively. These parameters for renal dysfunction and immunological abnormalities were statistically correlated. These phenotypes found in the female reproductive organs were completely inhibited by ovariectomy. Further, the female cotton rats with pyometra tended to show more severe chronic kidney disease phenotypes and immunological abnormalities than those without pyometra; these changes were inhibited in ovariectomized cotton rats. With regard to renal histopathology, cystic lesions, inflammation, and fibrosis were ameliorated by ovariectomy. Notably, the immunostaining intensity of estrogen receptor α and estrogen receptor β were weak in the healthy kidneys, but both estrogen receptors were strongly induced in the renal tubules showing cystic changes. In conclusion, the close correlations among female reproductive organ-associated abnormalities, immunological abnormalities, and renal dysfunction characterize the chronic kidney disease features of female cotton rats. Thus, the cotton rat is a unique rodent model to elucidate the pathological crosstalk between chronic kidney disease and sex-related factors. Impact statement The increasing number of elderly individuals in the overall population has led to a concomitant age-related increase in chronic kidney disease. Moreover, the global prevalence of patients with chronic kidney disease is gradually increasing, which poses a serious public health problem. The limited number of spontaneous chronic kidney disease animal models, which resemble chronic kidney disease pathogenesis in elderly individuals, is a major limitation in the development of experimental and curative medicines for chronic kidney disease. This pathological study clarified that sex-related factors, including hormones, and abnormalities of the female reproductive system, such as pyometra, are closely associated with chronic kidney disease development by using cotton rats ( Sigmodon hispidus). Further, ovariectomy inhibited the phenotypes of the female reproductive system, immunological abnormalities, and chronic kidney disease. Thus, this laboratory rodent serves as a novel and useful spontaneous chronic kidney disease model to elucidate the candidate disease factors and the pathogenesis of chronic kidney disease both in human and experimental medicine.

Phylogenetic perspectives on the evolution of functional hermaphroditism in teleost fishes.

PubMed

Erisman, Brad E; Petersen, Christopher W; Hastings, Philip A; Warner, Robert R

2013-10-01

Hermaphroditism is taxonomically widespread among teleost fishes and takes on many forms including simultaneous, protogynous, and protandrous hermaphroditism, bidirectional sex change, and androdioecy. The proximate mechanisms that influence the timing, incidence, and forms of hermaphroditism in fishes are supported by numerous theoretical and empirical studies on their mating systems and sexual patterns, but few have examined aspects of sex-allocation theory or the evolution of hermaphroditism for this group within a strict phylogenetic context. Fortunately, species-level phylogenetic reconstructions of the evolutionary history of many lineages of fishes have emerged, providing opportunities for understanding fine-scale evolutionary pathways and transformations of sex allocation. Examinations of several families of fishes with adequate data on phylogeny, patterns of sex allocation, mating systems, and with some form of hermaphroditism reveal that the evolution and expression of protogyny and other forms of sex allocation show little evidence of phylogenetic inertia within specific lineages but rather are associated with particular mating systems in accordance with prevalent theories about sex allocation. Transformations from protogyny to gonochorism in groupers (Epinephelidae), seabasses (Serranidae), and wrasses and parrotfishes (Labridae) are associated with equivalent transformations in the structure of mating groups from spawning of pairs to group spawning and related increases in sperm competition. Similarly, patterns of protandry, androdioecy, simultaneous hermaphroditism, and bidirectional sex change in other lineages (Aulopiformes, Gobiidae, and Pomacentridae) match well with particular mating systems in accordance with sex-allocation theory. Unlike other animals and plants, we did not find evidence that transitions between hermaphroditism and gonochorism required functional intermediates. Two instances in which our general conclusions might not hold include the expression of protandry in the Sparidae and the distribution of simultaneous hermaphroditism. In the Sparidae, the association of hypothesized mating systems and patterns of sex allocation were not always consistent with the size-advantage model (SAM), in that certain protandric sparids show evidence of intense sperm competition that should favor the expression of gonochorism. In the other case, simultaneous hermaphroditism does not occur in some groups of monogamous fishes, which are similar in ecology to the hermaphroditic serranines, suggesting that this form of sex allocation may be more limited by phylogenetic inertia. Overall, this work strongly supports sexual lability within teleost fishes and confirms evolutionary theories of sex allocation in this group of vertebrates.

Makalu: fast recoverable allocation of non-volatile memory

DOE PAGES

Bhandari, Kumud; Chakrabarti, Dhruva R.; Boehm, Hans-J.

2016-10-19

Byte addressable non-volatile memory (NVRAM) is likely to supplement, and perhaps eventually replace, DRAM. Applications can then persist data structures directly in memory instead of serializing them and storing them onto a durable block device. However, failures during execution can leave data structures in NVRAM unreachable or corrupt. In this paper, we present Makalu, a system that addresses non-volatile memory management. Makalu offers an integrated allocator and recovery-time garbage collector that maintains internal consistency, avoids NVRAM memory leaks, and is efficient, all in the face of failures. We show that a careful allocator design can support a less restrictive andmore » a much more familiar programming model than existing persistent memory allocators. Our allocator significantly reduces the per allocation persistence overhead by lazily persisting non-essential metadata and by employing a post-failure recovery-time garbage collector. Experimental results show that the resulting online speed and scalability of our allocator are comparable to well-known transient allocators, and significantly better than state-of-the-art persistent allocators.« less

Makalu: fast recoverable allocation of non-volatile memory

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

Bhandari, Kumud; Chakrabarti, Dhruva R.; Boehm, Hans-J.

Byte addressable non-volatile memory (NVRAM) is likely to supplement, and perhaps eventually replace, DRAM. Applications can then persist data structures directly in memory instead of serializing them and storing them onto a durable block device. However, failures during execution can leave data structures in NVRAM unreachable or corrupt. In this paper, we present Makalu, a system that addresses non-volatile memory management. Makalu offers an integrated allocator and recovery-time garbage collector that maintains internal consistency, avoids NVRAM memory leaks, and is efficient, all in the face of failures. We show that a careful allocator design can support a less restrictive andmore » a much more familiar programming model than existing persistent memory allocators. Our allocator significantly reduces the per allocation persistence overhead by lazily persisting non-essential metadata and by employing a post-failure recovery-time garbage collector. Experimental results show that the resulting online speed and scalability of our allocator are comparable to well-known transient allocators, and significantly better than state-of-the-art persistent allocators.« less

76 FR 29083 - Agriculture Priorities and Allocations System

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-19

... Vol. 76 Thursday, No. 97 May 19, 2011 Part III Department of Agriculture Farm Service Agency 7 CFR Part 789 Agriculture Priorities and Allocations System; Proposed Rule #0;#0;Federal Register / Vol. 76 , No. 97 / Thursday, May 19, 2011 / Proposed Rules#0;#0; [[Page 29084

Unequal power allocation for JPEG transmission over MIMO systems.

PubMed

Sabir, Muhammad Farooq; Bovik, Alan Conrad; Heath, Robert W

2010-02-01

With the introduction of multiple transmit and receive antennas in next generation wireless systems, real-time image and video communication are expected to become quite common, since very high data rates will become available along with improved data reliability. New joint transmission and coding schemes that explore advantages of multiple antenna systems matched with source statistics are expected to be developed. Based on this idea, we present an unequal power allocation scheme for transmission of JPEG compressed images over multiple-input multiple-output systems employing spatial multiplexing. The JPEG-compressed image is divided into different quality layers, and different layers are transmitted simultaneously from different transmit antennas using unequal transmit power, with a constraint on the total transmit power during any symbol period. Results show that our unequal power allocation scheme provides significant image quality improvement as compared to different equal power allocations schemes, with the peak-signal-to-noise-ratio gain as high as 14 dB at low signal-to-noise-ratios.

Decellularized Human Kidney Cortex Hydrogels Enhance Kidney Microvascular Endothelial Cell Maturation and Quiescence.

PubMed

Nagao, Ryan J; Xu, Jin; Luo, Ping; Xue, Jun; Wang, Yi; Kotha, Surya; Zeng, Wen; Fu, Xiaoyun; Himmelfarb, Jonathan; Zheng, Ying

2016-10-01

The kidney peritubular microvasculature is highly susceptible to injury from drugs and toxins, often resulting in acute kidney injury and progressive chronic kidney disease. Little is known about the process of injury and regeneration of human kidney microvasculature, resulting from the lack of appropriate kidney microvascular models that can incorporate the proper cells, extracellular matrices (ECMs), and architectures needed to understand the response and contribution of individual vascular components in these processes. In this study, we present methods to recreate the human kidney ECM (kECM) microenvironment by fabricating kECM hydrogels derived from decellularized human kidney cortex. The majority of native matrix proteins, such as collagen-IV, laminin, and heparan sulfate proteoglycan, and their isoforms were preserved in similar proportions as found in normal kidneys. Human kidney peritubular microvascular endothelial cells (HKMECs) became more quiescent when cultured on this kECM gel compared with culture on collagen-I-assessed using phenotypic, genotypic, and functional assays; whereas human umbilical vein endothelial cells became stimulated on kECM gels. We demonstrate for the first time that human kidney cortex can form a hydrogel suitable for use in flow-directed microphysiological systems. Our findings strongly suggest that selecting the proper ECM is a critical consideration in the development of vascularized organs on a chip and carries important implications for tissue engineering of all vascularized organs.

Hydrogen Sulfide in Hypertension and Kidney Disease of Developmental Origins.

PubMed

Hsu, Chien-Ning; Tain, You-Lin

2018-05-11

Adverse environments occurring during kidney development may produce long-term programming effects, namely renal programming, to create increased vulnerability to the development of later-life hypertension and kidney disease. Conversely, reprogramming is a strategy aimed at reversing the programming processes in early life, even before the onset of clinical symptoms, which may counter the rising epidemic of hypertension and kidney disease. Hydrogen sulfide (H₂S), the third gasotransmitter, plays a key role in blood pressure regulation and renal physiology. This review will first present the role of H₂S in the renal system and provide evidence for the links between H₂S signaling and the underlying mechanisms of renal programming, including the renin⁻angiotensin system, oxidative stress, nutrient-sensing signals, sodium transporters, and epigenetic regulation. This will be followed by potential H₂S treatment modalities that may serve as reprogramming strategies to prevent hypertension and kidney disease of developmental origins. These H₂S treatment modalities include precursors for H₂S synthesis, H₂S donors, and natural plant-derived compounds. Despite emerging evidence from experimental studies in support of reprogramming strategies targeting the H₂S signaling pathway to protect against hypertension and kidney disease of developmental origins, these results need further clinical translation.

Educational Systems and the Trade-Off between Labor Market Allocation and Equality of Educational Opportunity

ERIC Educational Resources Information Center

Bol, Thijs; van de Werfhorst, Herman G.

2013-01-01

Educational systems with a high level of tracking and vocational orientation have been shown to improve the allocation of school-leavers in the labor market. However, tracked educational systems are also known to increase inequality of educational opportunity. This presumed trade-off between equality and labor market preparation is clearly rooted…

Klotho and activin A in kidney injury: plasma Klotho is maintained in unilateral obstruction despite no upregulation of Klotho biosynthesis in the contralateral kidney.

PubMed

Nordholm, Anders; Mace, Maria L; Gravesen, Eva; Hofman-Bang, Jacob; Morevati, Marya; Olgaard, Klaus; Lewin, Ewa

2018-05-01

In a new paradigm of etiology related to chronic kidney disease-mineral and bone disorder (CKD-MBD), kidney injury may cause induction of factors in the injured kidney that are released into the circulation and thereby initiate and maintain renal fibrosis and CKD-MBD. Klotho is believed to ameliorate renal fibrosis and CKD-MBD, while activin A might have detrimental effects. The unilateral ureter obstruction (UUO) model is used here to examine this concept by investigating early changes related to renal fibrosis in the obstructed kidney, untouched contralateral kidney, and vasculature which might be affected by secreted factors from the obstructed kidney, and comparing with unilateral nephrectomized controls (UNX). Obstructed kidneys showed early Klotho gene and protein depletion, whereas plasma Klotho increased in both UUO and UNX rats, indicating an altered metabolism of Klotho. Contralateral kidneys had no compensatory upregulation of Klotho and maintained normal expression of the examined fibrosis-related genes, as did remnant UNX kidneys. UUO caused upregulation of transforming growth factor-β and induction of periostin and activin A in obstructed kidneys without changes in the contralateral kidneys. Plasma activin A doubled in UUO rats after 10 days while no changes were seen in UNX rats, suggesting secretion of activin A from the obstructed kidney with potentially systemic effects on CKD-MBD. As such, increased aortic sclerostin was observed in UUO rats compared with UNX and normal controls. The present results are in line with the new paradigm and show very early vascular effects of unilateral kidney fibrosis, supporting the existence of a new kidney-vasculature axis.

Toward a Multilevel Perspective on the Allocation of Educational Resources.

ERIC Educational Resources Information Center

Monk, David H.

1981-01-01

The importance of the following is demonstrated: (1) striking a balance between the attention given to resource allocation practices at macro compared to microlevels of decision making; and (2) learning more about how resource allocation decisions made at one level affect practices at other levels of the educational system. (Author/GK)

78 FR 45001 - Self-Regulatory Organizations; Miami International Securities Exchange LLC; Order Approving...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-25

... a minimum participation allocation of at least one (1) contract. Specifically, the proposal ensures that the DLMM will be allocated a minimum of one contract in situations where, due to the Exchange's... DLMM being allocated zero contracts. \\5\\ A ``Directed Order'' is an order entered into the System by an...

The International Fuel Tax Agreement (IFTA) and International Registration Plan (IRP) : allocating commercial fuel tax and registration fee payments across multiple jurisdictions.

DOT National Transportation Integrated Search

2007-02-01

This report provides: (1) an overview of the IFTA and IRP processes for allocating fuel tax revenues across jurisdictions; and (2) an assessment of these systems in regard to their effectiveness at allocating the tax and fee burden among commercial c...

Contrarian behavior in a complex adaptive system

NASA Astrophysics Data System (ADS)

Liang, Y.; An, K. N.; Yang, G.; Huang, J. P.

2013-01-01

Contrarian behavior is a kind of self-organization in complex adaptive systems (CASs). Here we report the existence of a transition point in a model resource-allocation CAS with contrarian behavior by using human experiments, computer simulations, and theoretical analysis. The resource ratio and system predictability serve as the tuning parameter and order parameter, respectively. The transition point helps to reveal the positive or negative role of contrarian behavior. This finding is in contrast to the common belief that contrarian behavior always has a positive role in resource allocation, say, stabilizing resource allocation by shrinking the redundancy or the lack of resources. It is further shown that resource allocation can be optimized at the transition point by adding an appropriate size of contrarians. This work is also expected to be of value to some other fields ranging from management and social science to ecology and evolution.

Research on allocation efficiency of the daisy chain allocation algorithm

NASA Astrophysics Data System (ADS)

Shi, Jingping; Zhang, Weiguo

2013-03-01

With the improvement of the aircraft performance in reliability, maneuverability and survivability, the number of the control effectors increases a lot. How to distribute the three-axis moments into the control surfaces reasonably becomes an important problem. Daisy chain method is simple and easy to be carried out in the design of the allocation system. But it can not solve the allocation problem for entire attainable moment subset. For the lateral-directional allocation problem, the allocation efficiency of the daisy chain can be directly measured by the area of its subset of attainable moments. Because of the non-linear allocation characteristic, the subset of attainable moments of daisy-chain method is a complex non-convex polygon, and it is difficult to solve directly. By analyzing the two-dimensional allocation problems with a "micro-element" idea, a numerical calculation algorithm is proposed to compute the area of the non-convex polygon. In order to improve the allocation efficiency of the algorithm, a genetic algorithm with the allocation efficiency chosen as the fitness function is proposed to find the best pseudo-inverse matrix.

Simulating Water Resource Disputes of Transboundary River: A Case Study of the Zhanghe River Basin, China

NASA Astrophysics Data System (ADS)

Yuan, Liang; He, Weijun; Liao, Zaiyi; Mulugeta Degefu, Dagmawi; An, Min; Zhang, Zhaofang

2018-01-01

Water resource disputes within transboundary river basin has been hindering the sustainable use of water resources and efficient management of environment. The problem is characterized by a complex information feedback loop that involves socio-economic and environmental systems. This paper presents a system dynamics based model that can simulate the dynamics of water demand, water supply, water adequacy and water allocation instability within a river basin. It was used for a case study in the Zhanghe River basin of China. The base scenario has been investigated for the time period between 2000 and 2050. The result shows that the Chinese national government should change the water allocation scheme of downstream Zhanghe River established in 1989, more water need to be allocated to the downstream cities and the actual allocation should be adjusted to reflect the need associated with the socio-economic and environmental changes within the region, and system dynamics improves the understanding of concepts and system interactions by offering a comprehensive and integrated view of the physical, social, economic, environmental, and political systems.

Systemic effect of mineral aggregate-based cements: histopathological analysis in rats

PubMed Central

Garcia, Lucas da Fonseca Roberti; Huck, Claudia; Magalhães, Fernando Augusto Cintra; de Souza, Pedro Paulo Chaves; de Souza Costa, Carlos Alberto

2017-01-01

Abstract Objective: Several studies reported the local tissue reaction caused by mineral aggregate-based cements. However, few studies have investigated the systemic effects promoted by these cements on liver and kidney when directly applied to connective tissue. The purpose of this in vivo study was to investigate the systemic effect of mineral aggregate-based cements on the livers and kidneys of rats. Material and Methods: Samples of Mineral Trioxide Aggregate (MTA) and a calcium aluminate-based cement (EndoBinder) containing different radiopacifiers were implanted into the dorsum of 40 rats. After 7 and 30 d, samples of subcutaneous, liver and kidney tissues were submitted to histopathological analysis. A score (0-3) was used to grade the inflammatory reaction. Blood samples were collected to evaluate changes in hepatic and renal functions of animals. Results: The moderate inflammatory reaction (2) observed for 7 d in the subcutaneous tissue decreased with time for all cements. The thickness of inflammatory capsules also presented a significant decrease with time (P<.05). Systemically, all cements caused adverse inflammatory reactions in the liver and kidney, being more evident for MTA, persisting until the end of the analysis. Liver functions increased significantly for MTA during 30 d (P<.05). Conclusion: The different cements induced to a locally limited inflammatory reaction. However, from the systemic point of view, the cements promoted significant inflammatory reactions in the liver and kidney. For MTA, the reactions were more accentuated. PMID:29211283

Anatomical Relationship Between the Kidney Collecting System and the Intrarenal Arteries in the Sheep: Contribution for a New Urological Model.

PubMed

Buys-Gonçalves, Gabriela Faria; De Souza, Diogo Benchimol; Sampaio, Francisco José Barcellos; Pereira-Sampaio, Marco Aurélio

2016-04-01

Previous studies have demonstrated that the pig collecting system heals after partial nephrectomy without closure. Recently, a study in sheep showed that partial nephrectomy without closure of the collecting system resulted in urinary leakage and urinoma. The aim of this study was to present detailed anatomical findings on the intrarenal anatomy of the sheep. Forty two kidneys were used to produce tridimensional endocasts of the collecting system together with the intrarenal arteries. A renal pelvis which displayed 11-19 (mean of 16) renal recesses was present. There were no calices present. The renal artery was singular in each kidney and gave two primary branches one to the dorsal surface and one to ventral surface. Dorsal and ventral branches of the renal artery were classified based on the relationship between their branching pattern and the collecting system as: type I (cranial and caudal segmental arteries), type II (cranial, middle and caudal segmental arteries) or type III (cranial, cranial middle, caudal middle, and caudal segmental arteries). Type I was the most common branching pattern for the dorsal and ventral branches of the renal artery. The arterial supply of the caudal pole of the sheep kidney supports its use as an experimental model due to the similarity to the human kidney. However, the lack of a retropelvic artery discourages the use of the cranial pole in experiments in which the arteries are an important aspect to be considered. © 2016 Wiley Periodicals, Inc.

A generic minimization random allocation and blinding system on web.

PubMed

Cai, Hongwei; Xia, Jielai; Xu, Dezhong; Gao, Donghuai; Yan, Yongping

2006-12-01

Minimization is a dynamic randomization method for clinical trials. Although recommended by many researchers, the utilization of minimization has been seldom reported in randomized trials mainly because of the controversy surrounding the validity of conventional analyses and its complexity in implementation. However, both the statistical and clinical validity of minimization were demonstrated in recent studies. Minimization random allocation system integrated with blinding function that could facilitate the implementation of this method in general clinical trials has not been reported. SYSTEM OVERVIEW: The system is a web-based random allocation system using Pocock and Simon minimization method. It also supports multiple treatment arms within a trial, multiple simultaneous trials, and blinding without further programming. This system was constructed with generic database schema design method, Pocock and Simon minimization method and blinding method. It was coded with Microsoft Visual Basic and Active Server Pages (ASP) programming languages. And all dataset were managed with a Microsoft SQL Server database. Some critical programming codes were also provided. SIMULATIONS AND RESULTS: Two clinical trials were simulated simultaneously to test the system's applicability. Not only balanced groups but also blinded allocation results were achieved in both trials. Practical considerations for minimization method, the benefits, general applicability and drawbacks of the technique implemented in this system are discussed. Promising features of the proposed system are also summarized.

Direct oral anticoagulants versus warfarin for preventing stroke and systemic embolic events among atrial fibrillation patients with chronic kidney disease.

PubMed

Kimachi, Miho; Furukawa, Toshi A; Kimachi, Kimihiko; Goto, Yoshihito; Fukuma, Shingo; Fukuhara, Shunichi

2017-11-06

Chronic kidney disease (CKD) is an independent risk factor for atrial fibrillation (AF), which is more prevalent among CKD patients than the general population. AF causes stroke or systemic embolism, leading to increased mortality. The conventional antithrombotic prophylaxis agent warfarin is often prescribed for the prevention of stroke, but risk of bleeding necessitates regular therapeutic monitoring. Recently developed direct oral anticoagulants (DOAC) are expected to be useful as alternatives to warfarin. To assess the efficacy and safety of DOAC including apixaban, dabigatran, edoxaban, and rivaroxaban versus warfarin among AF patients with CKD. We searched the Cochrane Kidney and Transplant Specialised Register (up to 1 August 2017) through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov. We included all randomised controlled trials (RCTs) which directly compared the efficacy and safety of direct oral anticoagulants (direct thrombin inhibitors or factor Xa inhibitors) with dose-adjusted warfarin for preventing stroke and systemic embolic events in non-valvular AF patients with CKD, defined as creatinine clearance (CrCl) or eGFR between 15 and 60 mL/min (CKD stage G3 and G4). Two review authors independently selected studies, assessed quality, and extracted data. We calculated the risk ratio (RR) and 95% confidence intervals (95% CI) for the association between anticoagulant therapy and all strokes and systemic embolic events as the primary efficacy outcome and major bleeding events as the primary safety outcome. Confidence in the evidence was assessing using GRADE. Our review included 12,545 AF participants with CKD from five studies. All participants were randomised to either DOAC (apixaban, dabigatran, edoxaban, and rivaroxaban) or dose-adjusted warfarin. Four studies used a central, interactive, automated response system for allocation concealment while the other did not specify concealment methods. Four studies were blinded while the other was partially open-label. However, given that all studies involved blinded evaluation of outcome events, we considered the risk of bias to be low. We were unable to create funnel plots due to the small number of studies, thwarting assessment of publication bias. Study duration ranged from 1.8 to 2.8 years. The large majority of participants included in this study were CKD stage G3 (12,155), and a small number were stage G4 (390). Of 12,545 participants from five studies, a total of 321 cases (2.56%) of the primary efficacy outcome occurred per year. Further, of 12,521 participants from five studies, a total of 617 cases (4.93%) of the primary safety outcome occurred per year. DOAC appeared to probably reduce the incidence of stroke and systemic embolism events (5 studies, 12,545 participants: RR 0.81, 95% CI 0.65 to 1.00; moderate certainty evidence) and to slightly reduce the incidence of major bleeding events (5 studies, 12,521 participants: RR 0.79, 95% CI 0.59 to 1.04; low certainty evidence) in comparison with warfarin. Our findings indicate that DOAC are as likely as warfarin to prevent all strokes and systemic embolic events without increasing risk of major bleeding events among AF patients with kidney impairment. These findings should encourage physicians to prescribe DOAC in AF patients with CKD without fear of bleeding. The major limitation is that the results of this study chiefly reflect CKD stage G3. Application of the results to CKD stage G4 patients requires additional investigation. Furthermore, we could not assess CKD stage G5 patients. Future reviews should assess participants at more advanced CKD stages. Additionally, we could not conduct detailed analyses of subgroups and sensitivity analyses due to lack of data.

Histology of the Urogenital System in the American Bullfrog (Rana catesbeiana), with Emphasis on Male Reproductive Morphology.

PubMed

Rheubert, Justin L; Cook, Hanna E; Siegel, Dustin S; Trauth, Stanley E

2017-10-01

Previous studies have revealed variations in the urogenital system morphology of amphibians. Recently, the urogenital system of salamanders was reviewed and terminology was synonymized across taxa. Discrepancies exist in the terminology describing the urogenital system of anurans, which prompted our group to develop a complete, detailed description of the urogenital system in an anuran species and provide nomenclature that is synonymous with those of other amphibian taxa. In Rana catesbeiana, sperm mature within spermatocysts of the seminiferous tubule epithelia and are transported to a series of intratesticular ducts that exit the testes and merge to form vasa efferentia. Vasa efferentia converge into single longitudinal ducts (Bidder's ducts) on the lateral aspects of the kidneys. Branches from the longitudinal ducts merge with genital kidney renal tubules through renal corpuscles. The nephrons travel caudally and empty into the Wöffian ducts. Similar to salamanders, the caudal portion of the kidneys (termed the pelvic kidneys in salamanders) only possesses nephrons involved in urine formation, not sperm transport. Data from the present study provide a detailed description and synonymous nomenclature that can be used to make future comparative analyses between taxa more efficient.

Microsphere-Based Rapamycin Delivery, Systemic Versus Local Administration in a Rat Model of Renal Ischemia/Reperfusion Injury.

PubMed

Zandstra, Jurjen; van Beuge, Marike M; Zuidema, Johan; Petersen, Arjen H; Staal, Mark; Duque, Luisa F; Rodriguez, Sergio; Lathuile, Audrey A R; Veldhuis, Gert J; Steendam, Rob; Bank, Ruud A; Popa, Eliane R

2015-10-01

The increasing prevalence and treatment costs of kidney diseases call for innovative therapeutic strategies that prevent disease progression at an early stage. We studied a novel method of subcapsular injection of monodisperse microspheres, to use as a local delivery system of drugs to the kidney. We generated placebo- and rapamycin monodisperse microspheres to investigate subcapsular delivery of drugs. Using a rat model of acute kidney injury, subcapsular injection of placebo and rapamycin monodisperse microspheres (monospheres) was compared to subcutaneous injection, mimicking systemic administration. We did not find any adverse effects related to the delivery method. Irrespective of the injection site, a similar low dose of rapamycin was present in the circulation. However, only local intrarenal delivery of rapamycin from monospheres led to decreased macrophage infiltration and a significantly lower amount of myofibroblasts in the kidney, where systemic administration did not. Local delivery of rapamycin did cause a transient increase in the deposition of collagen I, but not of collagen III. We conclude that therapeutic effects can be increased when rapamycin is delivered subcapsularly by monospheres, which, combined with low systemic concentrations, may lead to an effective intrarenal delivery method.

78 FR 32296 - Second Allocation of Public Transportation Emergency Relief Funds in Response to Hurricane Sandy...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-29

... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Second Allocation of Public... disaster that affects public transportation systems. The Disaster Relief Appropriations Act provides $10.9... projected total recovery costs for the four most severely affected public transportation systems, not...

48 CFR 31.201-4 - Determining allocability.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Determining allocability. 31.201-4 Section 31.201-4 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... for the contract; (b) Benefits both the contract and other work, and can be distributed to them in...

Peptide and low molecular weight proteins based kidney targeted drug delivery systems.

PubMed

Xu, Pengfei; Zhang, Hailiang; Dang, Ruili; Jiang, Pei

2018-05-30

Renal disease is a worldwide public health problem, and unfortunately, the therapeutic index of regular drugs is limited. Thus, it is a great need to develop effective treatment strategies. Among the reported strategies, kidney-targeted drug delivery system is a promising method to increase renal efficacy and reduce extra-renal toxicity. In recent years, working as vehicles for targeted drug delivery, low molecular weight proteins (LMWP) and peptide have received immense attention due to their many advantages, such as selective accumulation in kidney, high drug loading capability, control over routes of biodegradation, convenience in modification at the amino terminus, and good biocompatibility. In this review, we describe the current LMWP and peptide carriers for kidney targeted drug delivery systems. In addition, we discuss different linking strategies between carriers and drugs. Furthermore, we briefly outline the current status and attempt to give an outlook on the further study. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

What we need to know about the effect of lithium on the kidney.

PubMed

Gong, Rujun; Wang, Pei; Dworkin, Lance

2016-12-01

Lithium has been a valuable treatment for bipolar affective disorders for decades. Clinical use of lithium, however, has been problematic due to its narrow therapeutic index and concerns for its toxicity in various organ systems. Renal side effects associated with lithium include polyuria, nephrogenic diabetes insipidus, proteinuria, distal renal tubular acidosis, and reduction in glomerular filtration rate. Histologically, chronic lithium nephrotoxicity is characterized by interstitial nephritis with microcyst formation and occasional focal segmental glomerulosclerosis. Nevertheless, this type of toxicity is uncommon, with the strongest risk factors being high serum levels of lithium and longer time on lithium therapy. In contrast, in experimental models of acute kidney injury and glomerular disease, lithium has antiproteinuric, kidney protective, and reparative effects. This paradox may be partially explained by lower lithium doses and short duration of therapy. While long-term exposure to higher psychiatric doses of lithium may be nephrotoxic, short-term low dose of lithium may be beneficial and ameliorate kidney and podocyte injury. Mechanistically, lithium targets glycogen synthase kinase-3β, a ubiquitously expressed serine/threonine protein kinase implicated in the processes of tissue injury, repair, and regeneration in multiple organ systems, including the kidney. Future studies are warranted to discover the exact "kidney-protective dose" of lithium and test the effects of low-dose lithium on acute and chronic kidney disease in humans. Copyright © 2016 the American Physiological Society.

What we need to know about the effect of lithium on the kidney

PubMed Central

Gong, Rujun; Wang, Pei

2016-01-01

Lithium has been a valuable treatment for bipolar affective disorders for decades. Clinical use of lithium, however, has been problematic due to its narrow therapeutic index and concerns for its toxicity in various organ systems. Renal side effects associated with lithium include polyuria, nephrogenic diabetes insipidus, proteinuria, distal renal tubular acidosis, and reduction in glomerular filtration rate. Histologically, chronic lithium nephrotoxicity is characterized by interstitial nephritis with microcyst formation and occasional focal segmental glomerulosclerosis. Nevertheless, this type of toxicity is uncommon, with the strongest risk factors being high serum levels of lithium and longer time on lithium therapy. In contrast, in experimental models of acute kidney injury and glomerular disease, lithium has antiproteinuric, kidney protective, and reparative effects. This paradox may be partially explained by lower lithium doses and short duration of therapy. While long-term exposure to higher psychiatric doses of lithium may be nephrotoxic, short-term low dose of lithium may be beneficial and ameliorate kidney and podocyte injury. Mechanistically, lithium targets glycogen synthase kinase-3β, a ubiquitously expressed serine/threonine protein kinase implicated in the processes of tissue injury, repair, and regeneration in multiple organ systems, including the kidney. Future studies are warranted to discover the exact “kidney-protective dose” of lithium and test the effects of low-dose lithium on acute and chronic kidney disease in humans. PMID:27122541

Allocation of Rehabilitation Services for Older Adults in the Ontario Home Care System.

PubMed

Armstrong, Joshua J; Sims-Gould, Joanie; Stolee, Paul

Background: Physiotherapy and occupational therapy services can play a critical role in maintaining or improving the physical functioning, quality of life, and overall independence of older home care clients. Despite their importance, however, there is limited understanding of the factors that influence how rehabilitation services are allocated to older home care clients. The aim of this pilot study was to develop a preliminary understanding of the factors that influence decisions to allocate rehabilitation therapy services to older clients in the Ontario home care system, as perceived by three stakeholder groups. Methods: Semi-structured interviews were conducted with 10 key informants from three stakeholder groups: case managers, service providers, and health system policymakers. Results: Drivers of the allocation of occupational therapy and physiotherapy for older adults included functional needs and postoperative care. Participants identified challenges in providing home care rehabilitation to older adults, including impaired cognition and limited capacity in the home care system. Conclusions: Considering the changing demands for home care services, knowledge of current practices across the home care system can inform efforts to optimize rehabilitation services for the growing number of older adults. Further research is needed to advance the understanding of, and optimize rehabilitation service allocation to, older frail clients with multiple morbidities. Developing novel decision-support mechanisms and standardized clinical care pathways for older client populations may be beneficial.

Detection of medical errors in kidney transplantation: a pilot study comparing proactive clinician debriefings to a hospital-wide incident reporting system.

PubMed

McElroy, Lisa M; Daud, Amna; Lapin, Brittany; Ross, Olivia; Woods, Donna M; Skaro, Anton I; Holl, Jane L; Ladner, Daniela P

2014-11-01

Rates of medical errors and adverse events remain high for patients who undergo kidney transplantation; they are particularly vulnerable because of the complexity of their disease and the kidney transplantation procedure. Although institutional incident-reporting systems are used in hospitals around the country, they often fail to capture a substantial proportion of medical errors. The goal of this study was to assess the ability of a proactive, web-based clinician safety debriefing to augment the information about medical errors and adverse events obtained via traditional incident reporting systems. Debriefings were sent to all individuals listed on operating room personnel reports for kidney transplantation surgeries between April 2010 and April 2011, and incident reports were collected for the same time period. The World Health Organization International Classification for Patient Safety was used to classify all issues reported. A total of 270 debriefings reported 334 patient safety issues (179 safety incidents, 155 contributing factors), and 57 incident reports reported 92 patient safety issues (56 safety incidents, 36 contributing factors). Compared with incident reports, more attending physicians completed the debriefings (32.0 vs 3.5%). The use of a proactive, web-based debriefing to augment an incident reporting system in assessing safety risks in kidney transplantation demonstrated increased information, more perspectives of a single safety issue, and increased breadth of participants. Copyright © 2014 Elsevier Inc. All rights reserved.

[Case allocation of extensive operations on head and neck within the German DRG system 2004-2007: what is the net result of the continued developments in case allocation?].

PubMed

Franz, D; Franz, K; Roeder, N; Hörmann, K; Fischer, R-J; Alberty, Jürgen

2007-07-01

When the German DRG system was implemented there was some doubt about whether patients with extensive head and neck surgery would be properly accounted for. Significant efforts have therefore been invested in analysis and case allocation of those in this group. The object of this study was to investigate whether the changes within the German DRG system have led to improved case allocation. Cost data received from 25 ENT departments on 518 prospective documented cases of extensive head and neck surgery were compared with data from the German institute dealing with remuneration in hospitals (InEK). Statistical measures used by InEK were used to analyse the quality of the overall system and the homogeneity of the individual case groups. The reduction of variance of inlier costs improved by about 107.3% from the 2004 version to the 2007 version of the German DRG system. The average coefficient of cost homogeneity rose by about 9.7% in the same period. Case mix index and DRG revenues were redistributed from less extensive to the more complex operations. Hospitals with large numbers of extensive operations and university hospitals will gain most benefit from this development. Appropriate case allocation of extensive operations on the head and neck has been improved by the continued development of the German DRG system culminating in the 2007 version. Further adjustments will be needed in the future.

Graph theoretical stable allocation as a tool for reproduction of control by human operators

NASA Astrophysics Data System (ADS)

van Nooijen, Ronald; Ertsen, Maurits; Kolechkina, Alla

2016-04-01

During the design of central control algorithms for existing water resource systems under manual control it is important to consider the interaction with parts of the system that remain under manual control and to compare the proposed new system with the existing manual methods. In graph theory the "stable allocation" problem has good solution algorithms and allows for formulation of flow distribution problems in terms of priorities. As a test case for the use of this approach we used the algorithm to derive water allocation rules for the Gezira Scheme, an irrigation system located between the Blue and White Niles south of Khartoum. In 1925, Gezira started with 300,000 acres; currently it covers close to two million acres.

A novel dynamic wavelength bandwidth allocation scheme over OFDMA PONs

NASA Astrophysics Data System (ADS)

Yan, Bo; Guo, Wei; Jin, Yaohui; Hu, Weisheng

2011-12-01

With rapid growth of Internet applications, supporting differentiated service and enlarging system capacity have been new tasks for next generation access system. In recent years, research in OFDMA Passive Optical Networks (PON) has experienced extraordinary development as for its large capacity and flexibility in scheduling. Although much work has been done to solve hardware layer obstacles for OFDMA PON, scheduling algorithm on OFDMA PON system is still under primary discussion. In order to support QoS service on OFDMA PON system, a novel dynamic wavelength bandwidth allocation (DWBA) algorithm is proposed in this paper. Per-stream QoS service is supported in this algorithm. Through simulation, we proved our bandwidth allocation algorithm performs better in bandwidth utilization and differentiate service support.

Imaging regional renal function parameters using radionuclide tracers

NASA Astrophysics Data System (ADS)

Qiao, Yi

A compartmental model is given for evaluating kidney function accurately and noninvasively. This model is cast into a parallel multi-compartment structure and each pixel region (picture element) of kidneys is considered as a single kidney compartment. The loss of radionuclide tracers from the blood to the kidney and from the kidney to the bladder are modelled in great detail. Both the uptake function and the excretion function of the kidneys can be evaluated pixel by pixel, and regional diagnostic information on renal function is obtained. Gamma Camera image data are required by this model and a screening test based renal function measurement is provided. The regional blood background is subtracted from the kidney region of interest (ROI) and the kidney regional rate constants are estimated analytically using the Kuhn-Pucker multiplier method in convex programming by considering the input/output behavior of the kidney compartments. The detailed physiological model of the peripheral compartments of the system, which is not available for most radionuclide tracers, is not required in the determination of the kidney regional rate constants and the regional blood background factors within the kidney ROI. Moreover, the statistical significance of measurements is considered to assure the improved statistical properties of the estimated kidney rate constants. The relations between various renal function parameters and the kidney rate constants are established. Multiple renal function measurements can be found from the renal compartmental model. The blood radioactivity curve and the regional (or total) radiorenogram determining the regional (or total) summed behavior of the kidneys are obtained analytically with the consideration of the statistical significance of measurements using convex programming methods for a single peripheral compartment system. In addition, a new technique for the determination of 'initial conditions' in both the blood compartment and the kidney compartment is presented. The blood curve and the radiorenogram are analyzed in great detail and a physiological analysis from the radiorenogram is given. Applications of Kuhn-Tucker multiplier methods are illustrated for the renal compartmental model in the field of nuclear medicine. Conventional kinetic data analysis methods, the maximum likehood method, and the weighted integration method are investigated and used for comparisons. Moreover, the effect of the blood background subtraction is shown by using the gamma camera images in man. Several functional images are calculated and the functional imaging technique is applied for evaluating renal function in man quantitatively and visually and compared with comments from a physician.

Linear Quadratic Tracking Design for a Generic Transport Aircraft with Structural Load Constraints

NASA Technical Reports Server (NTRS)

Burken, John J.; Frost, Susan A.; Taylor, Brian R.

2011-01-01

When designing control laws for systems with constraints added to the tracking performance, control allocation methods can be utilized. Control allocations methods are used when there are more command inputs than controlled variables. Constraints that require allocators are such task as; surface saturation limits, structural load limits, drag reduction constraints or actuator failures. Most transport aircraft have many actuated surfaces compared to the three controlled variables (such as angle of attack, roll rate & angle of side slip). To distribute the control effort among the redundant set of actuators a fixed mixer approach can be utilized or online control allocation techniques. The benefit of an online allocator is that constraints can be considered in the design whereas the fixed mixer cannot. However, an online control allocator mixer has a disadvantage of not guaranteeing a surface schedule, which can then produce ill defined loads on the aircraft. The load uncertainty and complexity has prevented some controller designs from using advanced allocation techniques. This paper considers actuator redundancy management for a class of over actuated systems with real-time structural load limits using linear quadratic tracking applied to the generic transport model. A roll maneuver example of an artificial load limit constraint is shown and compared to the same no load limitation maneuver.

Distributed Multi-Cell Resource Allocation with Price Based ICI Coordination in Downlink OFDMA Networks

NASA Astrophysics Data System (ADS)

Lv, Gangming; Zhu, Shihua; Hui, Hui

Multi-cell resource allocation under minimum rate request for each user in OFDMA networks is addressed in this paper. Based on Lagrange dual decomposition theory, the joint multi-cell resource allocation problem is decomposed and modeled as a limited-cooperative game, and a distributed multi-cell resource allocation algorithm is thus proposed. Analysis and simulation results show that, compared with non-cooperative iterative water-filling algorithm, the proposed algorithm can remarkably reduce the ICI level and improve overall system performances.

Diabetes

MedlinePlus

... pain, tingling, a loss of feeling, problems digesting food, and erectile dysfunction Kidney problems , which can lead to kidney failure Weakened immune system, which can lead to more frequent infections Increased chance of having a heart attack or stroke

En bloc transplantation of horseshoe kidney in Korea

PubMed Central

Bang, Jun Bae; Lee, Jae Myeong; Oh, Chang-Kwon; Lee, Kyo Won; Park, Jae Berm; Kim, Sung Joo

2017-01-01

Transplantation of the horseshoe kidney can be performed en bloc or split into 2 grafts according to the vascular anomaly and the existence of the urinary collecting system in isthmus. From 2011 to 2014, there were 3 horseshoe kidney transplantations in Korea and transplantations were performed at 2 different centers. The transplantations were carried out successfully for all recipients without complications. All recipients have shown good graft kidney function after transplantation. No severe complication was revealed during follow-up period. We described the surgical technique used in the en bloc method to overcome various vascular anomalies and difficulties in choosing cannulation site and postoperative complications. En bloc transplantation of a horseshoe kidney is a useful strategy for patients with end-stage renal disease, and can provide favorable outcomes compared to the transplantation of a normal kidney. PMID:28289672

Understanding Kidney Disease: Toward the Integration of Regulatory Networks Across Species

PubMed Central

Ju, Wenjun; Brosius, Frank C.

2010-01-01

Animal models have long been useful in investigating both normal and abnormal human physiology. Systems biology provides a relatively new set of approaches to identify similarities and differences between animal models and humans that may lead to a more comprehensive understanding of human kidney pathophysiology. In this review, we briefly describe how genome-wide analyses of mouse models have helped elucidate features of human kidney diseases, discuss strategies to achieve effective network integration, and summarize currently available web-based tools that may facilitate integration of data across species. The rapid progress in systems biology and orthology, as well as the advent of web-based tools to facilitate these processes, now make it possible to take advantage of knowledge from distant animal species in targeted identification of regulatory networks that may have clinical relevance for human kidney diseases. PMID:21044762

Improved water allocation utilizing probabilistic climate forecasts: Short-term water contracts in a risk management framework

NASA Astrophysics Data System (ADS)

Sankarasubramanian, A.; Lall, Upmanu; Souza Filho, Francisco Assis; Sharma, Ashish

2009-11-01

Probabilistic, seasonal to interannual streamflow forecasts are becoming increasingly available as the ability to model climate teleconnections is improving. However, water managers and practitioners have been slow to adopt such products, citing concerns with forecast skill. Essentially, a management risk is perceived in "gambling" with operations using a probabilistic forecast, while a system failure upon following existing operating policies is "protected" by the official rules or guidebook. In the presence of a prescribed system of prior allocation of releases under different storage or water availability conditions, the manager has little incentive to change. Innovation in allocation and operation is hence key to improved risk management using such forecasts. A participatory water allocation process that can effectively use probabilistic forecasts as part of an adaptive management strategy is introduced here. Users can express their demand for water through statements that cover the quantity needed at a particular reliability, the temporal distribution of the "allocation," the associated willingness to pay, and compensation in the event of contract nonperformance. The water manager then assesses feasible allocations using the probabilistic forecast that try to meet these criteria across all users. An iterative process between users and water manager could be used to formalize a set of short-term contracts that represent the resulting prioritized water allocation strategy over the operating period for which the forecast was issued. These contracts can be used to allocate water each year/season beyond long-term contracts that may have precedence. Thus, integrated supply and demand management can be achieved. In this paper, a single period multiuser optimization model that can support such an allocation process is presented. The application of this conceptual model is explored using data for the Jaguaribe Metropolitan Hydro System in Ceara, Brazil. The performance relative to the current allocation process is assessed in the context of whether such a model could support the proposed short-term contract based participatory process. A synthetic forecasting example is also used to explore the relative roles of forecast skill and reservoir storage in this framework.

Scheduling language and algorithm development study. Volume 1, phase 2: Design considerations for a scheduling and resource allocation system

NASA Technical Reports Server (NTRS)

Morrell, R. A.; Odoherty, R. J.; Ramsey, H. R.; Reynolds, C. C.; Willoughby, J. K.; Working, R. D.

1975-01-01

Data and analyses related to a variety of algorithms for solving typical large-scale scheduling and resource allocation problems are presented. The capabilities and deficiencies of various alternative problem solving strategies are discussed from the viewpoint of computer system design.

IN VITRO COMPARISON OF MAXIMUM PRESSURE DEVELOPED BY IRRIGATION SYSTEMS IN A KIDNEY MODEL.

PubMed

Proietti, Silvia; Dragos, Laurian; Somani, Bhaskar K; Butticè, Salvatore; Talso, Michele; Emiliani, Esteban; Baghdadi, Mohammed; Giusti, Guido; Traxer, Olivier

2017-04-05

To evaluate in vitro the maximum pressure generated in an artificial kidney model when people of different levels of strengths used various irrigation systems. Fifteen people were enrolled and divided in 3 groups based on their strengths. Individual strength was evaluated according to the maximum pressure each participant was able to achieve using an Encore™ Inflator. The irrigation systems evaluated were: T-FlowTM Dual Port, HilineTM, continuous flow single action pumping system (SAPSTM) with the system close and open, Irri-flo IITM, a simple 60-ml syringe and PeditrolTM . Each irrigation system was connected to URF-V2 ureteroscope, which was inserted into an artificial kidney model. Each participant was asked to produce the maximum pressure possible with every irrigation device. Pressure was measured with the working channel (WC) empty, with a laser fiber and a basket inside. The highest pressure was achieved with the 60 ml-syringe system and the lowest with SAPS continuous version system (with continuous irrigation open), compared to the other irrigation devices (p< 0.0001). Irrespective of the irrigation system, there was a significant difference in the pressure between the WC empty and when occupied with the laser fiber or the basket inside it (p<0.0001). The stratification between the groups showed that the most powerful group could produce the highest pressure in the kidney model with all the irrigation devices in almost any situation. The exception to this was the T-Flow system, which was the only device where no statistical differences were detected among these groups. The use of irrigation systems can often generate excessive pressure in an artificial kidney model, especially with an unoccupied WC of the ureteroscope. Depending on the strength of force applied, very high pressure can be generated by most irrigation devices irrespective of whether the scope is occupied or not.

Lateral resolution testing of a novel developed confocal microscopic imaging system

NASA Astrophysics Data System (ADS)

Zhang, Xin; Zhang, Yunhai; Chang, Jian; Huang, Wei; Xue, Xiaojun; Xiao, Yun

2015-10-01

Laser scanning confocal microscope has been widely used in biology, medicine and material science owing to its advantages of high resolution and tomographic imaging. Based on a set of confirmatory experiments and system design, a novel confocal microscopic imaging system is developed. The system is composed of a conventional fluorescence microscope and a confocal scanning unit. In the scanning unit a laser beam coupling module provides four different wavelengths 405nm 488nm 561nm and 638nm which can excite a variety of dyes. The system works in spot-to-spot scanning mode with a two-dimensional galvanometer. A 50 microns pinhole is used to guarantee that stray light is blocked and only the fluorescence signal from the focal point can be received . The three-channel spectral splitter is used to perform fluorescence imaging at three different working wavelengths simultaneously. The rat kidney tissue slice is imaged using the developed confocal microscopic imaging system. Nucleues labeled by DAPI and kidney spherule curved pipe labeled by Alexa Fluor 488 can be imaged clearly and respectively, realizing the distinction between the different components of mouse kidney tissue. The three-dimensional tomographic imaging of mouse kidney tissue is reconstructed by several two-dimensional images obtained in different depths. At last the resolution of the confocal microscopic imaging system is tested quantitatively. The experimental result shows that the system can achieve lateral resolution priority to 230nm.

Using Fiscal Data to Inform a State's Part C Allocation Methodology

ERIC Educational Resources Information Center

Greer, Maureen; Kilpatrick, Jamie; McCullough, Katy; Reid, Kellen

2016-01-01

This 2016 document is designed to provide state Part C staff with guidance on using fiscal data to analyze and revise their allocation methodology. Allocation methodology is the process -- including practices, strategies, procedures, and policies -- used by Part C state staff to equitably distribute funds to meet the needs of the system, including…

Carbon allocation to root and shoot systems of woody plants

Treesearch

Mark D. Coleman; J.G. Isebrands

1994-01-01

Carbon allocation to roots is of widespread and increasing interest due to a growing appreciation of the importance of root processes to whole-plant physiology and plant productivity. Carbon (C) allocation commonly refers to the distribution of C among plant organs (e.g., leaves, stems, roots); however, the term also applies to functional categories within organs such...

Harmonizing human-hydrological system under climate change: A scenario-based approach for the case of the headwaters of the Tagus River

NASA Astrophysics Data System (ADS)

Lobanova, Anastasia; Liersch, Stefan; Tàbara, J. David; Koch, Hagen; Hattermann, Fred F.; Krysanova, Valentina

2017-05-01

Conventional water management strategies, that serve solely socio-economic demands and neglect changing natural conditions of the river basins, face significant challenges in governing complex human-hydrological systems, especially in the areas with constrained water availability. In this study we assess the possibility to harmonize the inter-sectoral water allocation scheme within a highly altered human-hydrological system under reduction in water availability, triggered by projected climate change applying scenario-based approach. The Tagus River Basin headwaters, with significant disproportion in the water resources allocation between the environmental and socio-economic targets were taken as a perfect example of such system out of balance. We propose three different water allocation strategies for this region, including two conventional schemes and one imposing shift to sustainable water management and environmental restoration of the river. We combine in one integrated modelling framework the eco-hydrological process-based Soil and Water Integrated Model (SWIM), coupled with the conceptual reservoir and water allocation modules driven by the latest bias-corrected climate projections for the region and investigate possible water allocation scenarios in the region under constrained water availability in the future. Our results show that the socio-economic demands have to be re-considered and lowered under any water allocation strategy, as the climate impacts may significantly reduce water availability in the future. Further, we show that a shift to sustainable water management strategy and river restoration is possible even under reduced water availability. Finally, our results suggest that the adaptation of complex human-hydrological systems to climate change and a shift to a more sustainable water management are likely to be parts of one joint strategy to cope with climate change impacts.

Kidney damage in extracorporeal shock wave lithotripsy: a numerical approach for different shock profiles.

PubMed

Weinberg, Kerstin; Ortiz, Michael

2009-08-01

In shock-wave lithotripsy--a medical procedure to fragment kidney stones--the patient is subjected to hypersonic waves focused at the kidney stone. Although this procedure is widely applied, the physics behind this medical treatment, in particular the question of how the injuries to the surrounding kidney tissue arise, is still under investigation. To contribute to the solution of this problem, two- and three-dimensional numerical simulations of a human kidney under shock-wave loading are presented. For this purpose a constitutive model of the bio-mechanical system kidney is introduced, which is able to map large visco-elastic deformations and, in particular, material damage. The specific phenomena of cavitation induced oscillating bubbles is modeled here as an evolution of spherical pores within the soft kidney tissue. By means of large scale finite element simulations, we study the shock-wave propagation into the kidney tissue, adapt unknown material parameters and analyze the resulting stress states. The simulations predict localized damage in the human kidney in the same regions as observed in animal experiments. Furthermore, the numerical results suggest that in first instance the pressure amplitude of the shock wave impulse (and not so much its exact time-pressure profile) is responsible for damaging the kidney tissue.

Obesity and kidney disease: from population to basic science and the search for new therapeutic targets.

PubMed

Whaley-Connell, Adam; Sowers, James R

2017-08-01

The global burden of kidney disease is increasing strikingly in parallel with increases in obesity and diabetes. Indeed, chronic kidney disease (CKD) and end-stage renal disease (ESRD) coupled with comorbidities such as obesity, diabetes, and hypertension cost the health care system hundreds of billions of dollars in the US alone. The progression to ESRD in patients with obesity and diabetes continues despite widespread use of inhibitors of the renin-angiotensin-aldosterone system (RAAS) along with aggressive blood pressure and glycemic control in these high-risk populations. Thereby, it is increasingly important to better understand the underlying mechanisms involved in obesity-related CKD in order to develop new strategies that prevent or interrupt the progression of this costly disease. In this context, a key mechanism that drives development and progression of kidney disease in obesity is endothelial dysfunction and associated tubulointerstitial fibrosis. However, the precise interactive mechanisms in the development of aortic and kidney endothelial dysfunction and tubulointerstitial fibrosis remain unclear. Further, strategies specifically targeting kidney fibrosis have yielded inconclusive benefits in human studies. While clinical data support the benefits derived from inhibition of the RAAS, there is a tremendous amount of residual risk for the progression of kidney disease in individuals with obesity and diabetes. There is promising experimental data to suggest that exercise, targeting inflammation and oxidative stress, lowering uric acid, and targeting the mineralocorticoid receptor signaling and/or sodium channel inhibition could improve tubulointerstitial fibrosis and mitigate progression of kidney disease in persons with obesity and diabetes. Published by Elsevier Inc.

Epidemiology and outcome of tuberculosis in immunocompromised patients.

PubMed

Metry, Abdul Massiah; Al Salmi, Issa; Al-Abri, Seif; Al Ismaili, Faisal; Al Mahrouqi, Yaqoub; Hola, Alan; Shaheen, Faissal A M

2017-01-01

The United States Renal Data System showed 1.2% and 1.6% incidences of tuberculosis (TB) in patients on peritoneal dialysis and hemodialysis (HD), respectively. Kidney transplant (KTX) patients have higher rates. We studied the epidemiology and outcome of TB in patients with kidney dysfunction in a tertiary care hospital in the past decade. We examined data of patients with TB with and without kidney dysfunction from 2006 to 2015 through an electronic system. Statistical analysis was completed using Stata software, Chicago, IL, USA. We found 581 patients with active TB of whom 37 had renal dysfunction including chronic kidney disease, HD, and KTX. No difference was found in the prevalence, age, or gender predilection. The age ranged from 1 to 95 with a mean (standard deviation) of 38.6 (21.1) years. The incidence of TB is 3 per 100,000. The number of patients per year with active TB ranges from 52 to 128 and 3 to 4 in the general population and kidney dysfunction group, respectively. Sixty-five percent of patients with kidney dysfunction had pulmonary TB, 5% had pleurisy, and 30% had extrapulmonary TB. Eighty-four percent of patients with kidney dysfunction completed the course of treatment with 16% treatment failure and 0.4% developed multidrug-resistant TB; 8% were lost to follow-up and 8% died during the treatment period. This study showed no gender predilection for TB in the general population and immunocompromised. Duration of symptoms before diagnosis of TB was shorter in kidney dysfunction patients in comparison to the general population. TB cultures were the most positive tests whereas bronchoalveolar lavage and skin test were the least positive for detecting TB in the kidney dysfunction group. Improvement in registries and screening is required to enhance the capturing rate and detection among this group, as well as providing accurate data to health authorities and the public about the magnitude, future trends, treatments, and outcomes regarding TB in kidney dysfunction.

21 CFR 876.4650 - Water jet renal stone dislodger system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... dislodge stones from renal calyces (recesses of the pelvis of the kidney) by means of a pressurized stream of water through a conduit. The device is used in the surgical removal of kidney stones. (b... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Water jet renal stone dislodger system. 876.4650...

21 CFR 876.4650 - Water jet renal stone dislodger system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... dislodge stones from renal calyces (recesses of the pelvis of the kidney) by means of a pressurized stream of water through a conduit. The device is used in the surgical removal of kidney stones. (b... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Water jet renal stone dislodger system. 876.4650...

Role of renal biomarkers as predictors of acute kidney injury in cardiac surgery.

PubMed

Ghatanatti, Ravi; Teli, Anita; Tirkey, Sundeep Sanjivan; Bhattacharya, Subhankar; Sengupta, Gautam; Mondal, Ansuman

2014-02-01

Cardiac surgery is unique in using cardiopulmonary bypass in various clinical scenarios. Injury of vital organs is unavoidable in the perioperative period. Acute kidney injury is a consequence of the systemic inflammatory response after bypass, emboli, ischemia, and low cardiac output states, reportedly occurring in 30%-40% of open heart surgeries. Acute kidney injury is associated with increased morbidity, mortality, and cost. Many preventive measures (off-pump procedures, decreased crossclamp time, pulsatile flow, adequate hydration) are taken in the perioperative period to avoid organ injury, but in vain. Traditionally, blood urea, serum creatinine, and creatinine clearance rate were applied for prediction of acute kidney injury. The recent emergence of biomarkers such as neutrophil gelatinase-associated lipocalin, cystatin C, liver-type fatty acid binding protein, interleukin-18, kidney injury molecule-1, and tetrahydrobiopterin have helped in detecting acute kidney injury long before the rise of serum creatinine. These biomarkers can also be used as tools for predicting therapeutic effects in acute kidney injury and for monitoring drug toxicity. This review consolidates the knowledge of biomarkers and their application in acute kidney injury management.

A Score for Predicting Acute Kidney Injury After Coronary Artery Bypass Graft Surgery in an Asian Population.

PubMed

Mithiran, Harish; Kunnath Bonney, Glenn; Bose, Saideep; Subramanian, Srinivas; Zhe Yan, Zan Ng; Zong En, Seth Yeak; Papadimas, Evangelos; Chauhan, Ishaan; MacLaren, Graeme; Kofidis, Theodoros

2016-10-01

To develop a scoring system to predict acute kidney injury in Asian patients after coronary artery bypass grafting. A retrospective analysis of data collected in an institutional cardiac database. A tertiary academic hospital in a large metropolitan city. The study comprised 954 patients with coronary artery disease. All patients underwent coronary artery bypass surgery with cardiopulmonary bypass but did not undergo any other concomitant procedures. The main outcome measured was acute kidney injury as defined by the Acute Kidney Injury Network criteria. The following 6 clinical variables were independent predictors of kidney injury: age>60 years, diabetes requiring insulin, estimated glomerular filtration rate<60 mL/min/1.73 m(2), ejection fraction<40%, cardiopulmonary bypass time>140 minutes, and aortic cross-clamp time>100 minutes. These variables were used to develop the Singapore Acute Kidney Injury score. The Singapore Acute Kidney Injury score is a simple way to predict, at the time of admission to the intensive care unit, an Asian patient's risk of developing acute kidney injury after coronary artery bypass surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

Current costing models: are they suitable for allocating health resources? The example of fall injury prevention in Australia.

PubMed

Moller, Jerry

2005-01-01

The example of fall injury among older people is used to define and illustrate how current Australian systems for allocation of health resources perform for funding emerging public health issues. While the examples are Australian, the allocation and priority setting methods are common in the health sector in all developed western nations. With an ageing population the number of falls injuries in Australia and the cost of treatment will rise dramatically over the next 20-50 years. Current methods of allocating funds within the health system are not well suited to meeting this coming epidemic. The information requirements for cost-benefit and cost-effectiveness measures cannot be met. Marginal approaches to health funding are likely to continue to fund already well-funded treatment or politically driven prevention processes and to miss the opportunity for new prevention initiatives in areas that do not have a high political profile. Fall injury is one of many emerging areas that struggle to make claims for funding because the critical mass of intervention and evidence of its impact is not available. The beneficiaries of allocation failure may be those who treat the disease burden that could have been easily prevented. Changes to allocation mechanisms, data systems and new initiative funding practices are required to ensure that preventative strategies are able to compete on an equal footing with treatment approaches for mainstream health funding.

Two-dimensional priority-based dynamic resource allocation algorithm for QoS in WDM/TDM PON networks

NASA Astrophysics Data System (ADS)

Sun, Yixin; Liu, Bo; Zhang, Lijia; Xin, Xiangjun; Zhang, Qi; Rao, Lan

2018-01-01

Wavelength division multiplexing/time division multiplexing (WDM/TDM) passive optical networks (PON) is being viewed as a promising solution for delivering multiple services and applications. The hybrid WDM / TDM PON uses the wavelength and bandwidth allocation strategy to control the distribution of the wavelength channels in the uplink direction, so that it can ensure the high bandwidth requirements of multiple Optical Network Units (ONUs) while improving the wavelength resource utilization. Through the investigation of the presented dynamic bandwidth allocation algorithms, these algorithms can't satisfy the requirements of different levels of service very well while adapting to the structural characteristics of mixed WDM / TDM PON system. This paper introduces a novel wavelength and bandwidth allocation algorithm to efficiently utilize the bandwidth and support QoS (Quality of Service) guarantees in WDM/TDM PON. Two priority based polling subcycles are introduced in order to increase system efficiency and improve system performance. The fixed priority polling subcycle and dynamic priority polling subcycle follow different principles to implement wavelength and bandwidth allocation according to the priority of different levels of service. A simulation was conducted to study the performance of the priority based polling in dynamic resource allocation algorithm in WDM/TDM PON. The results show that the performance of delay-sensitive services is greatly improved without degrading QoS guarantees for other services. Compared with the traditional dynamic bandwidth allocation algorithms, this algorithm can meet bandwidth needs of different priority traffic class, achieve low loss rate performance, and ensure real-time of high priority traffic class in terms of overall traffic on the network.

Method, apparatus and system for managing queue operations of a test bench environment

DOEpatents

Ostler, Farrell Lynn

2016-07-19

Techniques and mechanisms for performing dequeue operations for agents of a test bench environment. In an embodiment, a first group of agents are each allocated a respective ripe reservation and a second set of agents are each allocated a respective unripe reservation. Over time, queue management logic allocates respective reservations to agents and variously changes one or more such reservations from unripe to ripe. In another embodiment, an order of servicing agents allocated unripe reservations is based on relative priorities of the unripe reservations with respect to one another. An order of servicing agents allocated ripe reservations is on a first come, first served basis.

A stream-scale model to optimize the water allocation for Small Hydropower Plants and the application to traditional systems

NASA Astrophysics Data System (ADS)

Razurel, Pierre; Niayifar, Amin; Perona, Paolo

2017-04-01

Hydropower plays an important role in supplying worldwide energy demand where it contributes to approximately 16% of global electricity production. Although hydropower, as an emission-free renewable energy, is a reliable source of energy to mitigate climate change, its development will increase river exploitation. The environmental impacts associated with both small hydropower plants (SHP) and traditional dammed systems have been found to the consequence of changing natural flow regime with other release policies, e.g. the minimal flow. Nowadays, in some countries, proportional allocation rules are also applied aiming to mimic the natural flow variability. For example, these dynamic rules are part of the environmental guidance in the United Kingdom and constitute an improvement in comparison to static rules. In a context in which the full hydropower potential might be reached in a close future, a solution to optimize the water allocation seems essential. In this work, we present a model that enables to simulate a wide range of water allocation rules (static and dynamic) for a specific hydropower plant and to evaluate their associated economic and ecological benefits. It is developed in the form of a graphical user interface (GUI) where, depending on the specific type of hydropower plant (i.e., SHP or traditional dammed system), the user is able to specify the different characteristics (e.g., hydrological data and turbine characteristics) of the studied system. As an alternative to commonly used policies, a new class of dynamic allocation functions (non-proportional repartition rules) is introduced (e.g., Razurel et al., 2016). The efficiency plot resulting from the simulations shows the environmental indicator and the energy produced for each allocation policies. The optimal water distribution rules can be identified on the Pareto's frontier, which is obtained by stochastic optimization in the case of storage systems (e.g., Niayifar and Perona, submitted) and by direct simulation for small hydropower ones (Razurel et al., 2016). Compared to proportional and constant minimal flows, economic and ecological efficiencies are found to be substantially improved in the case of using non-proportional water allocation rules for both SHP and traditional systems.

The roles of dominos and nonsimultaneous chains in kidney paired donation.

PubMed

Gentry, S E; Montgomery, R A; Swihart, B J; Segev, D L

2009-06-01

Efforts to expand kidney paired donation have included matching nondirected donors (NDDs) to incompatible pairs. In domino paired donation (DPD), an NDD gives to the recipient of an incompatible pair, beginning a string of simultaneous transplants that ends with a living donor giving to a recipient on the deceased donor waitlist. Recently, nonsimultaneous extended altruistic donor (NEAD) chains were introduced. In a NEAD chain, the last donor of the string of transplants initiated by an NDD is reserved to donate at a later time. Our aim was to project the impact of each of these strategies over 2 years of operation for paired donation programs that also allocate a given number of NDDs. Each NDD facilitated an average of 1.99 transplants using DPD versus 1.90 transplants using NEAD chains (p = 0.3), or 1.0 transplants donating directly to the waitlist (p < 0.001). NEAD chains did not yield more transplants compared with simultaneous DPD. Both DPD and NEAD chains relax reciprocality requirements and rebalance the blood-type distribution of donors. Because traditional paired donation will leave many incompatible pairs unmatched, novel approaches like DPD and NEAD chains must be explored if paired donation programs are to help a greater number of people.

Preliminary marked increase in the national organ donation rate in Israel following implementation of a new organ transplantation law.

PubMed

Lavee, J; Ashkenazi, T; Stoler, A; Cohen, J; Beyar, R

2013-03-01

Israel's organ donation rate has always been among the lowest in Western countries. In 2008 two new laws relevant to organ transplantation were introduced. The Brain-Respiratory Death Law defines the precise circumstances and mechanisms to determine brain death. The Organ Transplantation Law bans reimbursing transplant tourism involving organ trade, grants prioritization in organ allocation to candidates who are registered donors and removes disincentives for living donation by providing modest insurance reimbursement and social supportive services. The preliminary impact of the gradual introduction and implementation of these laws has been witnessed in 2011. Compared to previous years, in 2011 there was a significant increase in the number of deceased organ donors directly related to an increase in organ donation rate (from 7.8 to 11.4 donors per million population), in parallel to a significant increase in the number of new registered donors. In addition the number of kidney transplantations from living donors significantly increased in parallel to a significant decrease in the number of kidney transplantations performed abroad (from 155 in 2006 to 35 in 2011). The new laws have significantly increased both deceased and living organ donation while sharply decreasing transplant tourism. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

Stromal cells in tissue homeostasis: balancing regeneration and fibrosis.

PubMed

Rabelink, Ton J; Little, Melissa H

2013-12-01

The ageing population and the increasing prevalence of noncommunicable diseases such as diabetes and hypertension have led to an increased prevalence of chronic kidney disease. The generation of de novo kidney tissue from embryonic tissue and stem cells using tissue engineering approaches is being explored as an alternative to renal replacement therapy for treating the disease. It is, however, becoming clear that resident cells can not only induce fibrotic repair, but can also restore damaged kidney tissue. Mobilizing this innate capacity of the kidney to regenerate is of particular interest in the prevention of irreversible kidney failure. A novel concept is that the interaction of interstitial stromal cells with the local immune system may regulate tissue homeostasis and the balance between tissue repair and fibrosis. Mesenchymal stromal cells (MSCs), in particular, may enhance the intrinsic reparative capabilities of the kidney. This Perspectives article considers the innate regenerative potential of the kidney in the context of ongoing studies of MSC therapy.

Vitamin D: the iceberg nutrient.

PubMed

Armas, Laura A G; Heaney, Robert P

2011-03-01

The understanding of vitamin D's role in human health has recently expanded. It is now recognized as more than a hormone activated in the kidney only for calcium homeostasis. It is metabolized and used by virtually every cell in the body. Patients with chronic kidney disease have a deficit in their kidney production of 1,25(OH)(2)D and have classically been treated with calcitriol or its active analogues. Despite often having lower systemic levels of 1,25(OH)(2)D, patients with chronic kidney disease retain the capability of extra renal production of 1,25(OH)(2)D. This has far reaching implications for their health. This review examines clinical trials and observations in 3 areas that impact chronic kidney disease patients. Cancer, cardiovascular disease and infections are responsible for much of the morbidity and mortality in this patient population. We will discuss vitamin D's role in these disease states with a focus on the chronic kidney disease patient. Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Integrated Kidney Exosome Analysis for the Detection of Kidney Transplant Rejection.

PubMed

Park, Jongmin; Lin, Hsing-Ying; Assaker, Jean Pierre; Jeong, Sangmoo; Huang, Chen-Han; Kurdi, A; Lee, Kyungheon; Fraser, Kyle; Min, Changwook; Eskandari, Siawosh; Routray, Sujit; Tannous, Bakhos; Abdi, Reza; Riella, Leonardo; Chandraker, Anil; Castro, Cesar M; Weissleder, Ralph; Lee, Hakho; Azzi, Jamil R

2017-11-28

Kidney transplant patients require life-long surveillance to detect allograft rejection. Repeated biopsy, albeit the clinical gold standard, is an invasive procedure with the risk of complications and comparatively high cost. Conversely, serum creatinine or urinary proteins are noninvasive alternatives but are late markers with low specificity. We report a urine-based platform to detect kidney transplant rejection. Termed iKEA (integrated kidney exosome analysis), the approach detects extracellular vesicles (EVs) released by immune cells into urine; we reasoned that T cells, attacking kidney allografts, would shed EVs, which in turn can be used as a surrogate marker for inflammation. We optimized iKEA to detect T-cell-derived EVs and implemented a portable sensing system. When applied to clinical urine samples, iKEA revealed high level of CD3-positive EVs in kidney rejection patients and achieved high detection accuracy (91.1%). Fast, noninvasive, and cost-effective, iKEA could offer new opportunities in managing transplant recipients, perhaps even in a home setting.

Megalin-mediated specific uptake of chitosan/siRNA nanoparticles in mouse kidney proximal tubule epithelial cells enables AQP1 gene silencing.

PubMed

Gao, Shan; Hein, San; Dagnæs-Hansen, Frederik; Weyer, Kathrin; Yang, Chuanxu; Nielsen, Rikke; Christensen, Erik I; Fenton, Robert A; Kjems, Jørgen

2014-01-01

RNAi-based strategies provide a great therapeutic potential for treatment of various human diseases including kidney disorders, but face the challenge of in vivo delivery and specific targeting. The chitosan delivery system has previously been shown to target siRNA specifically to the kidneys in mice when administered intravenously. Here we confirm by 2D and 3D bioimaging that chitosan formulated siRNA is retained in the kidney for more than 48 hours where it accumulates in proximal tubule epithelial cells (PTECs), a process that was strongly dependent on the molecular weight of chitosan. Chitosan/siRNA nanoparticles, administered to chimeric mice with conditional knockout of the megalin gene, distributed almost exclusively in cells that expressed megalin, implying that the chitosan/siRNA particle uptake was mediated by a megalin-dependent endocytotic pathway. Knockdown of the water channel aquaporin 1 (AQP1) by up to 50% in PTECs was achieved utilizing the systemic i.v. delivery of chitosan/AQP1 siRNA in mice. In conclusion, specific targeting PTECs with the chitosan nanoparticle system may prove to be a useful strategy for knockdown of specific genes in PTECs, and provides a potential therapeutic strategy for treating various kidney diseases.

Megalin-Mediated Specific Uptake of Chitosan/siRNA Nanoparticles in Mouse Kidney Proximal Tubule Epithelial Cells Enables AQP1 Gene Silencing

PubMed Central

Gao, Shan; Hein, San; Dagnæs-Hansen, Frederik; Weyer, Kathrin; Yang, Chuanxu; Nielsen, Rikke; Christensen, Erik I; Fenton, Robert A; Kjems, Jørgen

2014-01-01

RNAi-based strategies provide a great therapeutic potential for treatment of various human diseases including kidney disorders, but face the challenge of in vivo delivery and specific targeting. The chitosan delivery system has previously been shown to target siRNA specifically to the kidneys in mice when administered intravenously. Here we confirm by 2D and 3D bioimaging that chitosan formulated siRNA is retained in the kidney for more than 48 hours where it accumulates in proximal tubule epithelial cells (PTECs), a process that was strongly dependent on the molecular weight of chitosan. Chitosan/siRNA nanoparticles, administered to chimeric mice with conditional knockout of the megalin gene, distributed almost exclusively in cells that expressed megalin, implying that the chitosan/siRNA particle uptake was mediated by a megalin-dependent endocytotic pathway. Knockdown of the water channel aquaporin 1 (AQP1) by up to 50% in PTECs was achieved utilizing the systemic i.v. delivery of chitosan/AQP1 siRNA in mice. In conclusion, specific targeting PTECs with the chitosan nanoparticle system may prove to be a useful strategy for knockdown of specific genes in PTECs, and provides a potential therapeutic strategy for treating various kidney diseases. PMID:25157280

48 CFR 211.602 - General.

Code of Federal Regulations, 2010 CFR

2010-10-01

... DEFENSE ACQUISITION PLANNING DESCRIBING AGENCY NEEDS Priorities and Allocations 211.602 General. DoD implementation of the Defense Priorities and Allocations System is in DoDD 4400.1, Defense Production Act...

48 CFR 211.602 - General.

Code of Federal Regulations, 2012 CFR

2012-10-01

... DEFENSE ACQUISITION PLANNING DESCRIBING AGENCY NEEDS Priorities and Allocations 211.602 General. DoD implementation of the Defense Priorities and Allocations System is in DoDD 4400.1, Defense Production Act...

48 CFR 211.602 - General.

Code of Federal Regulations, 2013 CFR

2013-10-01

... DEFENSE ACQUISITION PLANNING DESCRIBING AGENCY NEEDS Priorities and Allocations 211.602 General. DoD implementation of the Defense Priorities and Allocations System is in DoDD 4400.1, Defense Production Act...

48 CFR 211.602 - General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... DEFENSE ACQUISITION PLANNING DESCRIBING AGENCY NEEDS Priorities and Allocations 211.602 General. DoD implementation of the Defense Priorities and Allocations System is in DoDD 4400.1, Defense Production Act...

48 CFR 211.602 - General.

Code of Federal Regulations, 2014 CFR

2014-10-01

... DEFENSE ACQUISITION PLANNING DESCRIBING AGENCY NEEDS Priorities and Allocations 211.602 General. DoD implementation of the Defense Priorities and Allocations System is in DoDD 4400.1, Defense Production Act...

Motion-Based Piloted Simulation Evaluation of a Control Allocation Technique to Recover from Pilot Induced Oscillations

NASA Technical Reports Server (NTRS)

Craun, Robert W.; Acosta, Diana M.; Beard, Steven D.; Leonard, Michael W.; Hardy, Gordon H.; Weinstein, Michael; Yildiz, Yildiray

2013-01-01

This paper describes the maturation of a control allocation technique designed to assist pilots in the recovery from pilot induced oscillations (PIOs). The Control Allocation technique to recover from Pilot Induced Oscillations (CAPIO) is designed to enable next generation high efficiency aircraft designs. Energy efficient next generation aircraft require feedback control strategies that will enable lowering the actuator rate limit requirements for optimal airframe design. One of the common issues flying with actuator rate limits is PIOs caused by the phase lag between the pilot inputs and control surface response. CAPIO utilizes real-time optimization for control allocation to eliminate phase lag in the system caused by control surface rate limiting. System impacts of the control allocator were assessed through a piloted simulation evaluation of a non-linear aircraft simulation in the NASA Ames Vertical Motion Simulator. Results indicate that CAPIO helps reduce oscillatory behavior, including the severity and duration of PIOs, introduced by control surface rate limiting.

Improved personalized recommendation based on a similarity network

NASA Astrophysics Data System (ADS)

Wang, Ximeng; Liu, Yun; Xiong, Fei

2016-08-01

A recommender system helps individual users find the preferred items rapidly and has attracted extensive attention in recent years. Many successful recommendation algorithms are designed on bipartite networks, such as network-based inference or heat conduction. However, most of these algorithms define the resource-allocation methods for an average allocation. That is not reasonable because average allocation cannot indicate the user choice preference and the influence between users which leads to a series of non-personalized recommendation results. We propose a personalized recommendation approach that combines the similarity function and bipartite network to generate a similarity network that improves the resource-allocation process. Our model introduces user influence into the recommender system and states that the user influence can make the resource-allocation process more reasonable. We use four different metrics to evaluate our algorithms for three benchmark data sets. Experimental results show that the improved recommendation on a similarity network can obtain better accuracy and diversity than some competing approaches.

A Review of Function Allocation and En Route Separation Assurance

NASA Technical Reports Server (NTRS)

Lewis, Timothy A.; Aweiss, Arwa S.; Guerreiro, Nelson M.; Daiker, Ronald J.

2016-01-01

Today's air traffic control system has reached a limit to the number of aircraft that can be safely managed at the same time. This air traffic capacity bottleneck is a critical problem along the path to modernization for air transportation. The design of the next separation assurance system to address this problem is a cornerstone of air traffic management research today. This report reviews recent work by NASA and others in the areas of function allocation and en route separation assurance. This includes: separation assurance algorithms and technology prototypes; concepts of operations and designs for advanced separation assurance systems; and specific investigations into air-ground and human-automation function allocation.

Sequential Targeting of CD52 and TNF Allows Early Minimization Therapy in Kidney Transplantation: From a Biomarker to Targeting in a Proof-Of-Concept Trial

PubMed Central

Viklicky, Ondrej; Hruba, Petra; Tomiuk, Stefan; Schmitz, Sabrina; Gerstmayer, Bernhard; Sawitzki, Birgit; Miqueu, Patrick; Mrazova, Petra; Tycova, Irena; Svobodova, Eva; Honsova, Eva; Janssen, Uwe

2017-01-01

Background There is high medical need for safe long-term immunosuppression monotherapy in kidney transplantation. Selective targeting of post-transplant alloantigen-(re)activated effector-T cells by anti-TNF antibodies after global T cell depletion may allow safe drug minimization, however, it is unsolved what might be the best maintenance monotherapy. Methods In this open, prospective observational single-centre trial, 20 primary deceased donor kidney transplant recipients received 2x20 mg Alemtuzumab (d0/d1) followed by 5 mg/kg Infliximab (d2). For 14 days all patients received only tacrolimus, then they were allocated to either receive tacrolimus (TAC, n = 13) or sirolimus (SIR, n = 7) monotherapy, respectively. Protocol biopsies and extensive immune monitoring were performed and patients were followed-up for 60 months. Results TAC-monotherapy resulted in excellent graft survival (5yr 92%, 95%CI: 56.6–98.9) and function, normal histology, and no proteinuria. Immune monitoring revealed low intragraft inflammation (urinary IP-10) and hints for the development of operational tolerance signature in the TAC- but not SIR-group. Remarkably, the TAC-monotherapy was successful in all five presensitized (ELISPOT+) patients. However, recruitment into SIR-arm was stopped (after n = 7) because of high incidence of proteinuria and acute/chronic rejection in biopsies. No opportunistic infections occurred during follow-up. Conclusions In conclusion, our novel fast-track TAC-monotherapy protocol is likely to be safe and preliminary results indicated an excellent 5-year outcome, however, a full–scale study will be needed to confirm our findings. Trial Registration EudraCT Number: 2006-003110-18 PMID:28085915

Evaluation of Flagging Criteria of United States Kidney Transplant Center Performance: How to Best Define Outliers?

PubMed

Schold, Jesse D; Miller, Charles M; Henry, Mitchell L; Buccini, Laura D; Flechner, Stuart M; Goldfarb, David A; Poggio, Emilio D; Andreoni, Kenneth A

2017-06-01

Scientific Registry of Transplant Recipients report cards of US organ transplant center performance are publicly available and used for quality oversight. Low center performance (LP) evaluations are associated with changes in practice including reduced transplant rates and increased waitlist removals. In 2014, Scientific Registry of Transplant Recipients implemented new Bayesian methodology to evaluate performance which was not adopted by Center for Medicare and Medicaid Services (CMS). In May 2016, CMS altered their performance criteria, reducing the likelihood of LP evaluations. Our aims were to evaluate incidence, survival rates, and volume of LP centers with Bayesian, historical (old-CMS) and new-CMS criteria using 6 consecutive program-specific reports (PSR), January 2013 to July 2015 among adult kidney transplant centers. Bayesian, old-CMS and new-CMS criteria identified 13.4%, 8.3%, and 6.1% LP PSRs, respectively. Over the 3-year period, 31.9% (Bayesian), 23.4% (old-CMS), and 19.8% (new-CMS) of centers had 1 or more LP evaluation. For small centers (<83 transplants/PSR), there were 4-fold additional LP evaluations (52 vs 13 PSRs) for 1-year mortality with Bayesian versus new-CMS criteria. For large centers (>183 transplants/PSR), there were 3-fold additional LP evaluations for 1-year mortality with Bayesian versus new-CMS criteria with median differences in observed and expected patient survival of -1.6% and -2.2%, respectively. A significant proportion of kidney transplant centers are identified as low performing with relatively small survival differences compared with expected. Bayesian criteria have significantly higher flagging rates and new-CMS criteria modestly reduce flagging. Critical appraisal of performance criteria is needed to assess whether quality oversight is meeting intended goals and whether further modifications could reduce risk aversion, more efficiently allocate resources, and increase transplant opportunities.

Evaluation of the Protective Role of Glycine max Seed Extract (Soybean Oil) in Drug-Induced Nephrotoxicity in Experimental Rats.

PubMed

Ramasamy, Anand; Jothivel, Nandhakumar; Das, Saibal; Swapna, A; Albert, Alice Padmini; Barnwal, Preeti; Babu, Dinesh

2017-09-28

This study was conducted to evaluate the nephroprotective effect of Glycine max seed extract (soybean oil) against gentamicin- and rifampicin-induced nephrotoxicity in Sprague-Dawley rats and to compare its effects with those of vitamin E, which has well-established antioxidant and nephroprotective effects. Sixty male Sprague-Dawley rats (body weight 150-210 g) were divided into 10 groups. The first five groups were treated for 14 consecutive days with normal saline (5 ml/kg, by mouth [p.o.]); gentamicin (80 mg/kg intraperitoneally [i.p.]); gentamicin (80 mg/kg, i.p.) + vitamin E (250 mg/kg p.o.); gentamicin (80 mg/kg i.p.) + soybean oil (2.5 ml/kg p.o.); and gentamicin (80 mg/kg, i.p.) + soybean oil (5 ml/kg p.o.), respectively. For the next five groups, the same group allocation was done, but gentamicin was replaced with rifampicin (1 g/kg i.p.). Various biomarkers for nephrotoxicity in serum and urine were evaluated along with histopathological examination of kidneys. Analysis of variance (ANOVA) was done following Tukey's multiple comparison test; p < .05 was considered significant. Soybean oil in both doses significantly (p < .005) decreased serum blood urea nitrogen, creatinine, urea, uric acid and urine volume, kidney weight, urinary sodium, urinary potassium, and total protein and significantly (p < .005) increased serum total protein and urine creatinine in gentamicin- and rifampicin-treated animals, exhibiting nephroprotective effects. Soybean oil also showed strong antioxidant effects, causing significant (p < .005) increase in kidney homogenate catalases, glutathione peroxidase, and superoxide dismutase and significant (p < .005) decrease in lipid peroxidase in gentamicin- and rifampicin-treated animals. Soybean oil demonstrated good nephroprotective activity due to antioxidant effects.

Kidney organ donation: developing family practice initiatives to reverse inertia

PubMed Central

2010-01-01

Background Kidney transplantation is associated with greater long term survival rates and improved quality of life compared with dialysis. Continuous growth in the number of patients with kidney failure has not been matched by an increase in the availability of kidneys for transplantation. This leads to long waiting lists, higher treatment costs and negative health outcomes. Discussion Misunderstandings, public uncertainty and issues of trust in the medical system, that limit willingness to be registered as a potential donor, could be addressed by community dissemination of information and new family practice initiatives that respond to individuals' personal beliefs and concerns regarding organ donation and transplantation. Summary Tackling both personal and public inertia on organ donation is important for any community oriented kidney donation campaign. PMID:20478042

Succinate receptor GPR91 provides a direct link between high glucose levels and renin release in murine and rabbit kidney

PubMed Central

Toma, Ildikó; Kang, Jung Julie; Sipos, Arnold; Vargas, Sarah; Bansal, Eric; Hanner, Fiona; Meer, Elliott; Peti-Peterdi, János

2008-01-01

Diabetes mellitus is the most common and rapidly growing cause of end-stage renal disease in developed countries. A classic hallmark of early diabetes mellitus includes activation of the renin-angiotensin system (RAS), which may lead to hypertension and renal tissue injury, but the mechanism of RAS activation is elusive. Here we identified a paracrine signaling pathway in the kidney in which high levels of glucose directly triggered the release of the prohypertensive hormone renin. The signaling cascade involved the local accumulation of succinate and activation of the kidney-specific G protein–coupled metabolic receptor, GPR91, in the glomerular endothelium as observed in rat, mouse, and rabbit kidney sections. Elements of signal transduction included endothelial Ca2+, the production of NO and prostaglandin (PGE2), and their paracrine actions on adjacent renin-producing cells. This GPR91 signaling cascade may serve to modulate kidney function and help remove metabolic waste products through renal hyperfiltration, and it could also link metabolic diseases, such as diabetes, or metabolic syndrome with RAS overactivation, systemic hypertension, and organ injury. PMID:18535668

Dialysis in rats with acute renal failure: evaluation of three different dialyzer membranes.

PubMed

Kränzlin, B; Gretz, N; Kirschfink, M; Mujais, S K

1996-11-01

Exposure to complement-activating cellulosic dialysis membranes has been claimed to adversely affect the course of acute renal failure (ARF). To test this hypothesis, male Sprague-Dawley rats were allocated to 2 groups: in Group 1, ARF was induced by bilateral renal artery clamping whereas in Group 2, animals underwent a sham procedure. In each group, rats were further allocated to undergo hemodialysis with either a Cuprophan, a Hemophan, or a polyacrylonitrile minidialyzer on Days 4 and 8 after surgery, or no dialysis. Renal function was measured by inulin clearance on the days after dialysis. Additionally, total complement activity (CH50) was estimated on Days 1, 2, 4, and 8, and complement factor C3 was detected immunohistochemically. The degree of renal failure and the rate of recovery of renal function were similar in all the ARF groups irrespective of whether they had undergone dialysis or not, or of the type of the dialysis membrane. Furthermore, there were no significant differences in the course of CH50 or in the amount and distribution of complement factor C3 in the kidney tissue between the rats of Groups 1 and 2. Our findings refute the hypothesis that in ischemic ARF exposure to complement-activating cellulosic dialysis membranes impairs the recovery of renal function in rats.

Acellular Mouse Kidney ECM can be Used as a Three-Dimensional Substrate to Test the Differentiation Potential of Embryonic Stem Cell Derived Renal Progenitors.

PubMed

Sambi, Manpreet; Chow, Theresa; Whiteley, Jennifer; Li, Mira; Chua, Shawn; Raileanu, Vanessa; Rogers, Ian M

2017-08-01

The development of strategies for tissue regeneration and bio-artificial organ development is based on our understanding of embryogenesis. Differentiation protocols attempt to recapitulate the signaling modalities of gastrulation and organogenesis, coupled with cell selection regimens to isolate the cells of choice. This strategy is impeded by the lack of optimal in vitro culture systems since traditional culture systems do not allow for the three-dimensional interaction between cells and the extracellular matrix. While artificial three-dimensional scaffolds are available, using the natural extracellular matrix scaffold is advantageous because it has a distinct architecture that is difficult to replicate. The adult extracellular matrix is predicted to mediate signaling related to tissue repair not embryogenesis but existing similarities between the two argues that the extracellular matrix will influence the differentiation of stem and progenitor cells. Previous studies using undifferentiated embryonic stem cells grown directly on acellular kidney ECM demonstrated that the acellular kidney supported cell growth but limited differentiation occurred. Using mouse kidney extracellular matrix and mouse embryonic stem cells we report that the extracellular matrix can support the development of kidney structures if the stem cells are first differentiated to kidney progenitor cells before being applied to the acellular organ.

Morphological observation of the horseshoe kidney with special reference to the vascular system in 2 Japanese cadavers.

PubMed

Nakamura, Yoichi; Yi, Shuang-Qin; Iimura, Akira; Terayama, Hayato; Naito, Munekazu; Itoh, Masahiro

2005-11-01

Two cases of the horseshoe kidney in Japanese cadaver were reported in this paper. The kidneys and their associated vessels in the retroperitoneal cavity were carefully examined, and the histological examination of the isthmus was performed. In Case 1, four arteries arose from the abdominal aorta. One right and two left renal arteries were distributed to the apical, upper, middle and posterior regions of the kidney, respectively, and the artery of isthmus entered the lower segments and the isthmus. In Case 2, six arteries arose from the abdominal aorta. Among three arteries arose from the inferior end of the aorta and entered the lower segments and the isthmus. Histological study revealed that the isthmuses consisted of collecting tubes, glomeruli and urinary tubules and fibrous connective tissue. The incidence of the horseshoe kidney during the dissecting practice at Tokyo Medical University in a period of 24 years from 1980 to 2003 was estimated to be 0.16% (2 out of the 1,219 cadavers). The anatomical and embryological significance of this anomaly and its associated vascular system were discussed. And the histology of the parenchymal structure of the isthmus in the horseshoe kidney containing either fibrous connective tissue or renal parenchyma was also analyzed in this report.

Lung-Kidney Cross-Talk in the Critically Ill Patient.

PubMed

Husain-Syed, Faeq; Slutsky, Arthur S; Ronco, Claudio

2016-08-15

Discoveries have emerged highlighting the complex nature of the interorgan cross-talk between the kidney and the lung. Vascular rigidity, neurohormonal activation, tissue hypoxia, and abnormal immune cell signaling have been identified as common pathways leading to the development and progression of chronic kidney disease. However, our understanding of the causal relationships between lung injury and kidney injury is not precise. This review discusses a number of features and mechanisms of renal dysfunction in pulmonary disorders in relation to respiratory acidosis, impaired gas exchange, systemic congestion, respiratory support/replacement therapies, and other issues relevant to the clinical care of these patients. Biotrauma due to injurious ventilatory strategies can lead to the release of mediators into the lung, which may then translocate into the systemic circulation and cause end-organ dysfunction, including renal dysfunction. Right ventricular dysfunction and congestive states may contribute to alterations of renal perfusion and oxygenation, leading to diuretic resistance and recurrent hospitalization. In patients with concomitant respiratory failure, noninvasive ventilation represents a promising treatment option for the correction of impaired renal microcirculation and endothelial dysfunction. In patients requiring extracorporeal membrane oxygenation, short- and long-term monitoring of kidney function is warranted, as they are at highest risk of developing acute kidney injury and fluid overload.

Nonadherence to immunosuppressive therapy in kidney transplant recipients: can technology help?

PubMed

Nerini, Erika; Bruno, Fulvio; Citterio, Franco; Schena, Francesco P

2016-10-01

End-stage kidney disease is a life-threatening condition that compels patients to accept either dialysis or transplant. Kidney transplantation is the best choice for patients with end-stage kidney disease because it ensures higher quality of life and longer survival rates than other choices, with less cost for the healthcare system. However, in order for renal recipients to maintain the functioning graft they must take lifelong immunosuppressive medications, with possible side effects and low medication adherence. It is known that low medication adherence in kidney transplant recipients may cause poor outcomes, chronic graft rejection, and graft failure. In this review, the authors give an overview of nonadherence in the transplant setting. In addition, they analyze the role of different technologies as an aid to improve adherence, with a focus on mobile-phone based solutions to monitor and enhance kidney transplant recipient compliance.

Kidney regeneration by xeno-embryonic nephrogenesis.

PubMed

Yokoo, Takashi; Fukui, Akira; Matsumoto, Kei; Kawamura, Tetsuya

2008-03-01

Establishment of a functional whole kidney de novo has not received much attention because of the formidable challenges and the slow pace of advances in this field of research. This situation has changed recently with publication of data revealing the catastrophic nature of Medicaid costs for dialysis-related diseases. An innovative approach is needed in our search for therapies for kidney diseases and to provide a substitute for dialysis as soon as possible. Regenerative medicine offers great hope for realizing this goal. We established a system by which human mesenchymal stem cells can differentiate into a functional renal unit using a program of nephrogenesis in a developing xeno-embryo. In this article, recent research in the field of developing whole kidneys is reviewed, and possible therapeutic applications for kidney diseases are proposed in combination with our knowledge of the emerging field of kidney stem cell biology.

Evidence of a heterogeneous tissue oxygenation: renal ischemia/reperfusion injury in a large animal model

NASA Astrophysics Data System (ADS)

Crane, Nicole J.; Huffman, Scott W.; Alemozaffar, Mehrdad; Gage, Frederick A.; Levin, Ira W.; Elster, Eric A.

2013-03-01

Renal ischemia that occurs intraoperatively during procedures requiring clamping of the renal artery (such as renal procurement for transplantation and partial nephrectomy for renal cancer) is known to have a significant impact on the viability of that kidney. To better understand the dynamics of intraoperative renal ischemia and recovery of renal oxygenation during reperfusion, a visible reflectance imaging system (VRIS) was developed to measure renal oxygenation during renal artery clamping in both cooled and warm porcine kidneys. For all kidneys, normothermic and hypothermic, visible reflectance imaging demonstrated a spatially distinct decrease in the relative oxy-hemoglobin concentration (%HbO2) of the superior pole of the kidney compared to the middle or inferior pole. Mean relative oxy-hemoglobin concentrations decrease more significantly during ischemia for normothermic kidneys compared to hypothermic kidneys. VRIS may be broadly applicable to provide an indicator of organ ischemia during open and laparoscopic procedures.

25 CFR 290.12 - What information must the tribal revenue allocation plan contain?

Code of Federal Regulations, 2010 CFR

2010-04-01

... incompetents' per capita payments by the parent or legal guardian; and (iii) Establishing a process, system, or... according to specific eligibility requirements and must utilize or establish a tribal court system, forum or administrative process for resolution of disputes concerning the allocation of net gaming revenues and the...

78 FR 65641 - Midcontinent Independent System Operator, Inc.; Notice of Technical Conference

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-01

... the allocation of real-time Revenue Sufficiency Guarantee (RSG) costs.\\1\\ In its order, the Commission... to discuss the issues raised by MISO's proposed revisions to its real-time RSG cost allocation... Independent System Operator, Inc.; Notice of Technical Conference By order dated October 16, 2013, in Docket...

Employing Needs-Based Funding Formulae--Some Unavoidable Tradeoffs

ERIC Educational Resources Information Center

Gilead, Tal; BenDavid-Hadar, Iris

2017-01-01

Purpose: The method by which the state allocates resources to its schooling system can serve as an important instrument for achieving desired improvements in levels of educational attainment, social equity and other social policy goals. In many school systems, the allocation of school resources is done according to a needs-based funding formula.…

Allocating Opportunities and the Social Economy of Education.

ERIC Educational Resources Information Center

Blair, John P.

The educational system is the most important of the institutions that bridge the family and the work place. Because of the role of bridge institutions in providing skills and screening that influence an individual's developmental path, it is important to understand how urban systems allocate scarce opportunities. The purpose of this essay is to…

Resources Allocation in Chinese Universities: Hierarchy, Academic Excellence, or Both?

ERIC Educational Resources Information Center

Ying, Qianwei; Fan, Yongmao; Luo, Danglun; Christensen, Tom

2017-01-01

Scholars are aware that the higher education sector in China is highly affected by its administrative system, but the questions of how and to what extent the Chinese administrative system impacts academic resources allocation have yet to be answered. By examining the empirical data from 2003 to 2010 of China's National Excellent Doctoral…

The Impact of a Flexible Assessment System on Students' Motivation, Performance and Attitude

ERIC Educational Resources Information Center

Pacharn, Parunchana; Bay, Darlene; Felton, Sandra

2013-01-01

We examine a flexible assessment system that allows students to determine the weights allocated to each course component and to re-allocate the weights in response to achieved scores. The flexibility is intended to encourage students' participation in the learning process, thereby promoting self-regulated learning skills. We compare this…

The Accounting System and Resource Allocation Reform in a Public University

ERIC Educational Resources Information Center

Spathis, Charalambos; Ananiadis, John

2004-01-01

This paper studies the accounting system reform practised in Greek universities since January 2000, and more particularly at the Aristotle University of Thessaloniki (AUTH). It specifically examines the allocation of resources to faculties by university management based on certain criteria. The AUTH is the largest public university in Greece and…

40 CFR 96.76 - Additional requirements to provide heat input data for allocations purposes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... TRADING PROGRAMS FOR STATE IMPLEMENTATION PLANS Monitoring and Reporting § 96.76 Additional requirements... to monitor and report NOX Mass emissions using a NOX concentration system and a flow system shall... chapter for any source located in a state developing source allocations based upon heat input. (b) The...

Multi-Robot Coalitions Formation with Deadlines: Complexity Analysis and Solutions

PubMed Central

2017-01-01

Multi-robot task allocation is one of the main problems to address in order to design a multi-robot system, very especially when robots form coalitions that must carry out tasks before a deadline. A lot of factors affect the performance of these systems and among them, this paper is focused on the physical interference effect, produced when two or more robots want to access the same point simultaneously. To our best knowledge, this paper presents the first formal description of multi-robot task allocation that includes a model of interference. Thanks to this description, the complexity of the allocation problem is analyzed. Moreover, the main contribution of this paper is to provide the conditions under which the optimal solution of the aforementioned allocation problem can be obtained solving an integer linear problem. The optimal results are compared to previous allocation algorithms already proposed by the first two authors of this paper and with a new method proposed in this paper. The results obtained show how the new task allocation algorithms reach up more than an 80% of the median of the optimal solution, outperforming previous auction algorithms with a huge reduction of the execution time. PMID:28118384

Multi-Robot Coalitions Formation with Deadlines: Complexity Analysis and Solutions.

PubMed

Guerrero, Jose; Oliver, Gabriel; Valero, Oscar

2017-01-01

Multi-robot task allocation is one of the main problems to address in order to design a multi-robot system, very especially when robots form coalitions that must carry out tasks before a deadline. A lot of factors affect the performance of these systems and among them, this paper is focused on the physical interference effect, produced when two or more robots want to access the same point simultaneously. To our best knowledge, this paper presents the first formal description of multi-robot task allocation that includes a model of interference. Thanks to this description, the complexity of the allocation problem is analyzed. Moreover, the main contribution of this paper is to provide the conditions under which the optimal solution of the aforementioned allocation problem can be obtained solving an integer linear problem. The optimal results are compared to previous allocation algorithms already proposed by the first two authors of this paper and with a new method proposed in this paper. The results obtained show how the new task allocation algorithms reach up more than an 80% of the median of the optimal solution, outperforming previous auction algorithms with a huge reduction of the execution time.

Modeling the allocation system: principles for robust design before restructuring.

PubMed

Mehrotra, Sanjay; Kilambi, Vikram; Gilroy, Richard; Ladner, Daniela P; Klintmalm, Goran B; Kaplan, Bruce

2015-02-01

The United Network for Organ Sharing is poised to resolve geographic disparity in liver transplantation and promote allocation based on medical urgency. At the time of writing, United Network for Organ Sharing is considering redistricting the organ procurement and transplantation network so that patient model for end-stage liver disease scores at transplant is more uniform across regions.We review the proposal with a systems-engineering focus and find that although the proposal is promising, it currently lacks evidence that it would perform effectively under realistic departures from its underlying data and assumptions. Moreover, we caution against prematurely focusing on redistricting as the only method to mitigate disparity. We describe system modeling principles which, if followed, will ensure that the redesigned allocation system is effective and efficient in achieving the intended goals.

Inter-rater reliability of postnatal ultrasound interpretation in infants with congenital hydronephrosis.

PubMed

Vemulakonda, V M; Wilcox, D T; Torok, M R; Hou, A; Campbell, J B; Kempe, A

2015-09-01

The most common measurements of hydronephrosis are the anterior-posterior (AP) diameter and the Society for Fetal Urology (SFU) grading systems. To date, the inter-rater reliability (IRR) of these measures has not been compared in the postnatal period. The objectives of this study were to compare the IRR of the AP diameter and the SFU grading system in infants and to determine whether ultrasound findings other than pelvicalyceal dilation are associated with higher SFU grades. Initial postnatal ultrasounds of infants seen from February 1, 2011, to January 31, 2012, with a primary diagnosis of congenital hydronephrosis were included for review. Ultrasound images were de-identified and reviewed by four pediatric urologists. IRR was calculated using the intraclass correlation (ICC) measure. A paired t test was used to compare ICCs. Associations between SFU grade and other ultrasound findings were tested using Chi-square or Fisher's exact tests. A total of 112 kidneys in 56 patients were reviewed. IRR of the SFU grading system was high (right kidney ICC = 0.83, left kidney ICC = 0.85); however, IRR of AP diameter measurement was higher (right kidney ICC = 00.97, left kidney ICC = 0.98; p < 0.001). Renal asymmetry (p < 0.001), echogenicity (p < 0.001), and parenchymal thinning (p < 0.001) were significantly associated with SFU grade 4 hydronephrosis on bivariable and multivariable analysis. The SFU grading system is associated with excellent IRR, although the AP diameter appears to have higher IRR. Physicians may consider ultrasound findings that are not explicitly included in the SFU system when assigning hydronephrosis grade, which may lead to variability in use of this classification system.

The ureteric bud epithelium: morphogenesis and roles in metanephric kidney patterning.

PubMed

Nagalakshmi, Vidya K; Yu, Jing

2015-03-01

The mammalian metanephric kidney is composed of two epithelial components, the collecting duct system and the nephron epithelium, that differentiate from two different tissues -the ureteric bud epithelium and the nephron progenitors, respectively-of intermediate mesoderm origin. The collecting duct system is generated through reiterative ureteric bud branching morphogenesis, whereas the nephron epithelium is formed in a process termed nephrogenesis, which is initiated with the mesenchymal-epithelial transition of the nephron progenitors. Ureteric bud branching morphogenesis is regulated by nephron progenitors, and in return, the ureteric bud epithelium regulates nephrogenesis. The metanephric kidney is physiologically divided along the corticomedullary axis into subcompartments that are enriched with specific segments of these two epithelial structures. Here, we provide an overview of the major molecular and cellular processes underlying the morphogenesis and patterning of the ureteric bud epithelium and its roles in the cortico-medullary patterning of the metanephric kidney. © 2015 Wiley Periodicals, Inc.

Comparing administered and market-based water allocation systems through a consistent agent-based modeling framework.

PubMed

Zhao, Jianshi; Cai, Ximing; Wang, Zhongjing

2013-07-15

Water allocation can be undertaken through administered systems (AS), market-based systems (MS), or a combination of the two. The debate on the performance of the two systems has lasted for decades but still calls for attention in both research and practice. This paper compares water users' behavior under AS and MS through a consistent agent-based modeling framework for water allocation analysis that incorporates variables particular to both MS (e.g., water trade and trading prices) and AS (water use violations and penalties/subsidies). Analogous to the economic theory of water markets under MS, the theory of rational violation justifies the exchange of entitled water under AS through the use of cross-subsidies. Under water stress conditions, a unique water allocation equilibrium can be achieved by following a simple bargaining rule that does not depend upon initial market prices under MS, or initial economic incentives under AS. The modeling analysis shows that the behavior of water users (agents) depends on transaction, or administrative, costs, as well as their autonomy. Reducing transaction costs under MS or administrative costs under AS will mitigate the effect that equity constraints (originating with primary water allocation) have on the system's total net economic benefits. Moreover, hydrologic uncertainty is shown to increase market prices under MS and penalties/subsidies under AS and, in most cases, also increases transaction, or administrative, costs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Ant Colony Optimization Algorithm for Centralized Dynamic Channel Allocation in Multi-Cell OFDMA Systems

NASA Astrophysics Data System (ADS)

Kim, Hyo-Su; Kim, Dong-Hoi

The dynamic channel allocation (DCA) scheme in multi-cell systems causes serious inter-cell interference (ICI) problem to some existing calls when channels for new calls are allocated. Such a problem can be addressed by advanced centralized DCA design that is able to minimize ICI. Thus, in this paper, a centralized DCA is developed for the downlink of multi-cell orthogonal frequency division multiple access (OFDMA) systems with full spectral reuse. However, in practice, as the search space of channel assignment for centralized DCA scheme in multi-cell systems grows exponentially with the increase of the number of required calls, channels, and cells, it becomes an NP-hard problem and is currently too complicated to find an optimum channel allocation. In this paper, we propose an ant colony optimization (ACO) based DCA scheme using a low-complexity ACO algorithm which is a kind of heuristic algorithm in order to solve the aforementioned problem. Simulation results demonstrate significant performance improvements compared to the existing schemes in terms of the grade of service (GoS) performance and the forced termination probability of existing calls without degrading the system performance of the average throughput.

Performance analysis of optimal power allocation in wireless cooperative communication systems

NASA Astrophysics Data System (ADS)

Babikir Adam, Edriss E.; Samb, Doudou; Yu, Li

2013-03-01

Cooperative communication has been recently proposed in wireless communication systems for exploring the inherent spatial diversity in relay channels.The Amplify-and-Forward (AF) cooperation protocols with multiple relays have not been sufficiently investigated even if it has a low complexity in term of implementation. We consider in this work a cooperative diversity system in which a source transmits some information to a destination with the help of multiple relay nodes with AF protocols and investigate the optimality of allocating powers both at the source and the relays system by optimizing the symbol error rate (SER) performance in an efficient way. Firstly we derive a closedform SER formulation for MPSK signal using the concept of moment generating function and some statistical approximations in high signal to noise ratio (SNR) for the system under studied. We then find a tight corresponding lower bound which converges to the same limit as the theoretical upper bound and develop an optimal power allocation (OPA) technique with mean channel gains to minimize the SER. Simulation results show that our scheme outperforms the equal power allocation (EPA) scheme and is tight to the theoretical approximation based on the SER upper bound in high SNR for different number of relays.

Predictors of kidney biopsy complication among patients with systemic lupus erythematosus.

PubMed

Chen, T K; Estrella, M M; Fine, D M

2012-07-01

Kidney biopsy is essential for the diagnosis and management of lupus nephritis. The risk of bleeding complication, however, is not defined in the systemic lupus erythematosus population. A retrospective cohort study was conducted to determine predictors of major and minor complications among patients with systemic lupus erythematosus undergoing percutaneous ultrasound-guided kidney biopsy. Major complications included bleeding necessitating intervention, hypotension requiring vasopressors or higher level of care or death. Minor complications included moderate or large (≥ 4 cm in largest diameter) perinephric hematoma, gross hematuria or voiding difficulties. All patients were observed for at least 23 h post-procedure. The overall incidence of bleeding was 10.5% (2.7% major, 7.8% minor). Adjusted logistic regression showed that for every 10,000 cells/mm(3) decrease in platelet count, risk for major and any complication increased by 27% (odds ratio 1.27; 95% confidence intervals 1.06-1.51; p = 0.01) and 8% (odds ratio 1.08; 95% confidence intervals 1.02-1.15; p = 0.01), respectively. Patients with a platelet count <150,000 cells/mm(3) were 30 times more likely to experience a major complication (p = 0.002). Other candidate predictors, including steroid exposure, kidney function, hematocrit and histopathology, were not significant. Kidney biopsies are well tolerated in patients with systemic lupus erythematosus. However, patients with pre-biopsy platelet counts <150,000 cells/mm(3) are at markedly increased risk for a major bleeding complication.