Comparison of renal ultrasonography and dimercaptosuccinic acid renal scintigraphy in febrile urinary tract infection.

PubMed

Ayazi, Parviz; Mahyar, Abolfazl; Noroozian, Elham; Esmailzadehha, Neda; Barikani, Ameneh

2015-12-01

Accurate and early diagnosis and appropriate treatment of patient with urinary tract infection (UTI) are essential for the prevention or restriction of permanent damage to the kidneys in children. The aim of this study was to compare renal ultrasonography (US) and dimercaptosuccinic acid (DMSA) renal scan in the diagnosis of patients with febrile urinary tract infection. This study involved the medical records of children with febrile urinary tract infection who were admitted to the children's hospital in Qazvin, Iran. Pyelonephritis was diagnosed on the basis of clinical symptoms, laboratory tests and abnormal DMSA renal scans. The criteria for abnormality of renal US were an increase or a decrease in diffuse or focal parenchymal echogenicity, loss of corticomedullary differentiation, kidney position irregularities, parenchymal reduction and increased kidney size. Of the 100 study patients, 23% had an abnormal US and 46% had an abnormal DMSA renal scan. Of the latter patients, 15 had concurrent abnormal US (P value ≤ 0.03, concordance rate: 18%). Renal US had a sensitivity of 32%, specificity of 85%, positive predictive value of 65% and negative predictive value of 60%. Of the 77 patients with normal US, 31 (40.2%) had an abnormal DMSA renal scan. Despite the benefits and accessibility of renal US, its value in the diagnosis of pyelonephritis is limited.

Vitamin C, glutathione, or lipoic acid did not decrease brain or kidney mercury in rats exposed to mercury vapor.

PubMed

Aposhian, H Vasken; Morgan, Daniel L; Queen, H L Sam; Maiorino, Richard M; Aposhian, Mary M

2003-01-01

Some medical practitioners prescribe GSH and vitamin C alone or in combination with DMPS or DMSA for patients with mercury exposure that is primarily due to the mercury vapor emitted by dental amalgams. This study tested the hypothesis that GSH, vitamin C, or lipoic acid alone or in combination with DMPS or DMSA would decrease brain mercury. Young rats were exposed to elemental mercury by individual nose cone, at the rate of 4.0 mg mercury per m3 air for 2 h per day for 7 consecutive days. After a 7-day equilibrium period, DMPS, DMSA, GSH, vitamin C, lipoic acid alone, or in combination was administered for 7 days and the brain and kidneys of the animals removed and analyzed for mercury by cold vapor atomic absorption. None of these regimens reduced the mercury content of the brain. Although DMPS or DMSA was effective in reducing kidney mercury concentrations, GSH, vitamin C, lipoic acid alone, or in combination were not. One must conclude that the palliative effect, if any, of GSH, vitamin C, or lipoic acid for treatment of mercury toxicity due to mercury vapor exposure does not involve mercury mobilization from the brain and kidney.

Safety and efficacy of oral DMSA therapy for children with autism spectrum disorders: Part A - Medical results

PubMed Central

Adams, James B; Baral, Matthew; Geis, Elizabeth; Mitchell, Jessica; Ingram, Julie; Hensley, Andrea; Zappia, Irene; Newmark, Sanford; Gehn, Eva; Rubin, Robert A; Mitchell, Ken; Bradstreet, Jeff; El-Dahr, Jane

2009-01-01

Background This study investigated the effect of oral dimercapto succinic acid (DMSA) therapy for children with autism spectrum disorders ages 3-8 years. Methods Phase 1 involved 65 children who received one round of DMSA (3 days). Participants who had high urinary excretion of toxic metals were selected to continue on to phase 2. In phase 2, 49 participants were randomly assigned in a double-blind design to receive an additional 6 rounds of either DMSA or placebo. Results DMSA greatly increased the excretion of lead, substantially increased excretion of tin and bismuth, and somewhat increased the excretion of thallium, mercury, antimony, and tungsten. There was some increase in urinary excretion of essential minerals, especially potassium and chromium. The Phase 1 single round of DMSA led to a dramatic normalization of RBC glutathione in almost all cases, and greatly improved abnormal platelet counts, suggesting a significant decrease in inflammation. Conclusion Overall, DMSA therapy seems to be reasonably safe, effective in removing several toxic metals (especially lead), dramatically effective in normalizing RBC glutathione, and effective in normalizing platelet counts. Only 1 round (3 days) was sufficient to improve glutathione and platelets. Additional rounds increased excretion of toxic metals. PMID:19852789

Cost and radiation exposure in the workup of febrile pediatric urinary tract infections.

PubMed

Michaud, Jason E; Gupta, Natasha; Baumgartner, Timothy S; Kim, Brian; Bosemani, Thangamadhan; Wang, Ming-Hsien

2016-06-15

Technetium-99m dimercaptosuccinic acid (DMSA) scans are often used in the evaluation of pediatric patients with febrile urinary tract infections (UTIs). Given the prevalence of febrile UTIs, we sought to quantify the cost, radiation exposure, and clinical utility of DMSA scans when compared with dedicated pediatric renal ultrasounds (RUSs). An institutional review board approved retrospective study of children under the age of 18 years evaluated at our institution for febrile UTIs between the years 2004-2013 was conducted. The patients had to meet all of the following inclusion criteria: a diagnosis of vesicoureteral reflux, a fever >38°C, a positive urine culture, and evaluation with a DMSA scan and RUS. A chart review was used to construct a cost analysis of technical and professional fees, radiographic results, and radiation dose equivalents. Overall, 104 children met the inclusion criteria. A total of 122 RUS and 135 DMSA scans were performed. The technical costs of a DMSA scan incurred a 35% cost premium as compared to an RUS. The average effective radiation dose of a single DMSA scan was 2.84 mSv. New radiographic findings were only identified on 7% of those patients who underwent greater than 1 DMSA scan. The utility of the unique information acquired from a DMSA scan as compared to a RUS in the evaluation of febrile UTI must be evaluated on an individual case-by-case basis given the increased direct costs and radiation exposure to the patient. Copyright © 2016 Elsevier Inc. All rights reserved.

Investigating febrile UTI in infants: is a cystogram necessary?

PubMed

Soccorso, G; Wagstaff, J; Blakey, K; Moss, G D; Broadley, P; Roberts, J P; Godbole, P

2010-04-01

Current imaging recommendations for investigating any infantile febrile urinary tract infection (UTI) are ultrasound scan (US), micturating cystourethrogram (MCUG) and dimercaptosuccinic acid (DMSA) scan. The aim of this retrospective cohort study was to determine the need and indications for MCUG in the investigation of a first febrile infantile UTI, as doubts have been raised over its benefit. Information on 427 infants who had undergone US, MCUG and DMSA following a first febrile UTI was prospectively recorded. The infants were divided into two groups: A (354) with normal renal US and B (73) with abnormal US. DMSA findings were correlated with findings on MCUG. Main outcome measures were incidence of recurrent UTIs, change in management or intervention as a result of MCUG, and outcome at discharge. Only 21/354 (6%) infants in Group A had both scarring on DMSA and vesicoureteric reflux (VUR), predominantly low-grade on MCUG. In Group B (abnormal US), 23/73 (32%) had scarring on DMSA and vesicoureteric reflux, predominantly high grade on MCUG. Of the infants with non-scarred kidneys, 73% had dilating reflux. Successful conservative treatment was performed in 423 infants, and 4 infants in Group B required surgery. We recommend US and DMSA in all infantile febrile UTI cases. Where US is normal, MCUG should be reserved for those cases with abnormal DMSA. Where US is abnormal, MCUG should be performed irrespective of findings on DMSA scan. A randomized prospective study is necessary to evaluate this further. Copyright © 2009 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Formation of Ag nanoframes with facilitation of dithiols.

PubMed

Cheng, Fong-Yu; Hu, Kuo-Wei; Yeh, Chen-Sheng

2012-03-01

Two-dimensional Ag nanoprisms readily formed Ag triangular nanoframes upon electron beam irradiation. Following meso-2, 3-dimercaptosuccinicacid (DMSA) ripening behavior, continuous electron beam exposure transformed a solid nanoplate into a core/void/shell morphology, which then evolved into a hollow nanoframe structure. TEM was used to observe the ripening and etching processes of Ag nanoprisms as a function of DMSA concentration and electron irradiation time. X-ray diffraction (XRD) and FT-IR analysis were conducted to characterize the Ag nanoprism structure and surface before and after treatment with DMSA. X-ray photoelectron spectroscopy (XPS) was used to determine surface chemical compositions and indicated DMSA was adsorbed on the Ag nanoprisms in the form of Ag(+)-S(-). Raman measurements provided evidence of a disulfide group on Ag nanoprisms. Similar organosulfur structures such as mercaptosuccinic acid and 2-mercaptoacetic acid were also studied with results suggesting that the two S-H groups of dithiol DMSA played the crucial role in nanoframe fabrication. Using the same strategy with DMSA, the nano-architecture can be extended to 2D nanodiscs yielding nanorings.

Recurrent urinary tract infections in young children: role of DMSA scintigraphy in detecting vesicoureteric reflux.

PubMed

Awais, Muhammad; Rehman, Abdul; Zaman, Maseeh Uz; Nadeem, Naila

2015-01-01

Performing micturiting cystourethrography (MCUG) in young children with recurrent urinary tract infections is controversial with discrepancy among the major guidelines. Previous studies have shown that a normal dimercaptosuccinic acid (DMSA) scintigraphy may avoid the need of performing MCUG for detecting vesicoureteric reflux in children with first febrile urinary tract infection. However, the role of DMSA for ruling out vesicoureteric reflux in children with recurrent urinary tract infections has not been studied. Approval from institutional ethical review committee was sought and the requirement of informed consent was waived. A total of 50 children under the age of 10 years with recurrent urinary tract infections underwent MCUG scan within 3 months of DMSA scan from January 2011 to September 2012 at our institution. Diagnosis of recurrent urinary tract infections and grading of vesicoureteric reflux was according to previously established standards. Abnormalities on DMSA scan - scarring, hydronephrosis and reduced differential renal function - were compared with presence of vesicoureteric reflux on MCUG. High-grade vesicoureteric reflux was noted on MCUG in 22 (44%) cases. The findings on DMSA included hydronephrosis and scarring in 25 (50%) and 25 (50%) cases, respectively. Abnormalities on DMSA scan for detecting the presence of high-grade vesicoureteric reflux on MCUG examination had sensitivity, specificity, positive and negative predictive values of 95.45%, 35.71%, 53.85% and 90.91%, respectively. The positive and negative likelihood ratios were 1.48 and 0.13 respectively. DMSA scan had high overall sensitivity and negative predictive value with a low negative likelihood ratio for ruling out high-grade vesicoureteric reflux on MCUG, which may obviate the need of invasive MCUG along with its associated drawbacks.

A moderate method for preparation DMSA coated Fe3O4 nanoparticles

NASA Astrophysics Data System (ADS)

Song, L. N.; Gu, N.; Zhang, Y.

2017-01-01

A moderate way to prepare water soluble magnetic Fe3O4 nanoparticles has been developed. Firstly, oleic acid coated Fe3O4 is prepared by coprecipitation. Second, oleic acid were replaced by 2,3-dimercaptosuccinnic acid (DMSA) to prepare DMSA/Fe3O4 in the mixed solution of n-hexane and acetone. After dialysis and filtration the DMSA/Fe3O4 can be transferred into distilled water to form stable Fe3O4 nanoparticle solutions. The TEM images indicated that the particles had spherical shape and the nanoparticles were found to be 12 nm with a relatively narrow size distribution with the hydrodynamic size of 30 nm. And the result of VSM shows that DMSA/Fe3O4 nanoparticles have a saturation magnetization of 31 emu/g. The IR spectra indicated that the iron oxide was located by carboxyl matrix.

Silymarin and dimercaptosuccinic acid ameliorate lead-induced nephrotoxicity and genotoxicity in rats.

PubMed

Alcaraz-Contreras, Y; Mendoza-Lozano, R P; Martínez-Alcaraz, E R; Martínez-Alfaro, M; Gallegos-Corona, M A; Ramírez-Morales, M A; Vázquez-Guevara, M A

2016-04-01

We studied the effect of silymarin and dimercaptosuccinic acid (DMSA), a chelating agent that was administered individually or in combination against lead (Pb) toxicity in rats. Wistar rats (200 ± 20) were randomly divided into five groups. Group A served as a control. Groups B-E were exposed to 2000 ppm of lead acetate in drinking water for 8 weeks. Group B served as a positive control. Group C received silymarin (100 mg kg(-1) orally) for 8 weeks. Group D received DMSA (75 mg kg(-1) orally) once daily for the last 5 days of treatment. Group E received DMSA and silymarin as groups C and D, respectively. The effect of Pb was evaluated and accordingly the treatments on blood lead levels (BLLs), renal system, and genotoxic effects were calculated using comet assay. The BLLs were significantly increased following the exposition of lead acetate. The administration of silymarin and DMSA provided reduction in BLLs. Silymarin and DMSA provided significant protection on the genotoxic effect of Pb. The toxic effect of Pb on kidneys was also studied. Our data suggest that silymarin and DMSA improve the renal histopathological lesions. © The Author(s) 2015.

Modelling dimercaptosuccinic acid (DMSA) plasma kinetics in humans.

PubMed

van Eijkeren, Jan C H; Olie, J Daniël N; Bradberry, Sally M; Vale, J Allister; de Vries, Irma; Meulenbelt, Jan; Hunault, Claudine C

2016-11-01

No kinetic models presently exist which simulate the effect of chelation therapy on lead blood concentrations in lead poisoning. Our aim was to develop a kinetic model that describes the kinetics of dimercaptosuccinic acid (DMSA; succimer), a commonly used chelating agent, that could be used in developing a lead chelating model. This was a kinetic modelling study. We used a two-compartment model, with a non-systemic gastrointestinal compartment (gut lumen) and the whole body as one systemic compartment. The only data available from the literature were used to calibrate the unknown model parameters. The calibrated model was then validated by comparing its predictions with measured data from three different experimental human studies. The model predicted total DMSA plasma and urine concentrations measured in three healthy volunteers after ingestion of DMSA 10 mg/kg. The model was then validated by using data from three other published studies; it predicted concentrations within a factor of two, representing inter-human variability. A simple kinetic model simulating the kinetics of DMSA in humans has been developed and validated. The interest of this model lies in the future potential to use it to predict blood lead concentrations in lead-poisoned patients treated with DMSA.

Biokinetics and dosimetric studies about 99mTc(V)-DMSA distribution.

PubMed

Correia, M B L; Magnata, S S L P; Silva, I M S; Catanho, M T J A; Lima, F F

2010-05-10

Research for radiodiagnostic agents should considerate biological critical parameters which will give own contribution on the absorbed dose. The dimercaptosuccinic acid (DMSA) labeled with (99m)Tc(V) is a radiopharmaceutical which has well established role in medullar thyroid carcinoma and has been proposed in evaluation of bone metastasis. This work studied the biokinetics and dosimetry of (99m)Tc(V)-DMSA by animal model. The (99m)Tc(V)-DMSA was prepared from a (III)DMSA kit alkalized. Mice (n=5) received (99m)Tc(V)DMSA i.v., they were sacrificed (30 min, 1h, 5h and 12h), the organs excised and the activities measured by a gamma counter. The results were evaluated based on %activity/g and the absorbed dose was estimated (MIRDOSE 3.0 program) by extrapolation of data from animal to human scale. The results showed the majority of organs reached the top uptake at 30 min, the greatest kidney uptake was (4.81 +/- 1.38)% activity/g, while the bone presented its highest uptake at 1h (5.49+/- 0.47)% activity/g, after 1h all the organs had activity exponential decrease. The biokinetic profile of (99m)Tc(V)-DMSA was well established, allowing quantifying of residence time, and the radiation dose estimates were made for this agent. About the absorbed dose, the preliminary results showed higher value to bone, being the soft tissue dose relatively low.

Interaction of chelating agents with cadmium in mice and rats.

PubMed Central

Eybl, V; Sýkora, J; Koutenský, J; Caisová, D; Schwartz, A; Mertl, F

1984-01-01

The influence of several chelating agents (CaDTPA, ZnDTPA, CaEDTA, ZnEDTA, DMSA, D-penicillamine and DMPS, DMP and DDC) on the acute toxicity of CdCl2 and on the whole body retention and tissue distribution of cadmium after the IV application of 115mCdCl2 was compared in mice. The chelating agents were applied immediately after the application of cadmium. CaDTPA, ZnDTPA and DMSA appeared to be the most effective antidotes. However, DMSA increased the amount of cadmium retained in kidneys. The treatment of cadmium-poisoned mice with the combination of DMSA (IP) and ZnDTPA (SC) (all the compounds were injected in equimolar dose) decreased the toxicity of cadmium more than treatment with one chelating agents (given in a 2:1 dose). However, by studying the effect of these chelating agents and their combination of the retention and distribution of Cd in mice, it was demonstrated that the combined application of the antidotes showed little or no improvement over the results obtained with the most effective of the individual components. In the urine of rats injected with CdCl2 and treated with the chelating agents (CaDTPA, ZnDTPA, DMSA), the presence of cadmium complexes was demonstrated. The formation of mixed ligand chelates in vivo was not proved. Experiments in mice given a single injection of 115mCd-labeled Cd complexes of DMPS, DMSA and DTPA showed a high retention of cadmium in the organisms after the IV application of CdDMPS and CdDMSA complexes. PMID:6734561

Evaluation of interobserver variability of parenchymal phase of Tc-99m mercaptoacetyltriglycine and Tc-99m dimercaptosuccinic acid renal scintigraphy

PubMed Central

Erdoğan, Zeynep; Abdülrezzak, Ümmühan; Silov, Güler; Özdal, Ayşegül; Turhal, Özgül

2014-01-01

Objective: The aim of this study was to investigate the variability in the interpretation of parenchymal abnormalities and to assess the differences in interpretation of routine renal scintigraphic findings on posterior view of technetium-99m dimercaptosuccinic acid (pvDMSA) scans and parenchymal phase of technetium-99m mercaptoacetyltriglycine (ppMAG3) scans by using standard criterions to make standardization and semiquantitative evaluation and to have more accurately correlation. Materials and Methods: Two experienced nuclear medicine physicians independently interpreted pvDMSA scans of 204 and ppMAG3 scans of 102 pediatric patients, retrospectively. Comparisons were made by visual inspection of pvDMSA scans, and ppMAG3 scans by using a grading system modified from Itoh et al. According to this, anatomical damage of the renal parenchyma was classified into six types: Grade 0-V. In the calculation of the agreement rates, Kendall correlation (tau-b) analysis was used. Results: According to our findings, excellent agreement was found for DMSA grade readings (DMSA-GR) (tau-b = 0.827) and good agreement for MAG3 grade readings (MAG3-GR) (tau-b = 0.790) between two observers. Most of clear parenchymal lesions detected on pvDMSA scans and ppMAG3 scans identified by observers equally. Studies with negative or minimal lesions reduced correlation degrees for both DMSA-GR and MAG3-GR. Conclusion: Our grading system can be used for standardization of the reports. We conclude that standardization of criteria and terminology in the interpretations may result in higher interobserver consistency, also improve low interobserver reproducibility and objectivity of renal scintigraphy reports. PMID:24761059

Metal chelators and neurotoxicity: lead, mercury, and arsenic.

PubMed

Bjørklund, Geir; Mutter, Joachim; Aaseth, Jan

2017-12-01

This article reviews the clinical use of the metal chelators sodium 2,3-dimercapto-1-propanesulfonate (DMPS), meso-2,3-dimercaptosuccinic acid (DMSA), and calcium disodium edetate (CaEDTA, calcium EDTA) in overexposure and poisonings with salts of lead (Pb), mercury (Hg), and arsenic (As). DMSA has considerably lower toxicity than the classic heavy metal antagonist BAL (2,3-dimercaptopropanol) and is also less toxic than DMPS. Because of its adverse effects, CaEDTA should be replaced by DMSA as the antidote of choice in treating moderate Pb poisoning. Combination therapy with BAL and CaEDTA was previously recommended in cases of severe acute Pb poisoning with encephalopathy. We suggest that BAL in such cases acted as a shuttling Pb transporter from the intra- to the extracellular space. The present paper discusses if a combination of the extracellularly distributed DMSA with the ionophore, Monensin may provide a less toxic combination for Pb mobilization by increasing both the efflux of intracellularly deposited Pb and the urinary Pb excretion. Anyhow, oral therapy with DMSA should be continued with several intermittent courses. DMPS and DMSA are also promising antidotes in Hg poisoning, whereas DMPS seems to be a more efficient agent against As poisoning. However, new insight indicates that a combination of low-dosed BAL plus DMPS could be a preferred antidotal therapy to obtain mobilization of the intracerebral deposits into the circulation for subsequent rapid urinary excretion.

Critical appraisal of the top-down approach for vesicoureteral reflux.

PubMed

Abdelhalim, Ahmed; Khoury, Antoine E

2017-06-01

Vesicoureteral reflux (VUR) has been linked to recurrent urinary tract infections (UTIs), renal scarring, hypertension, renal insufficiency and end-stage kidney disease. Different imaging strategies have been proposed to approach children presenting with UTI to sort out patients with significant VUR while minimizing patient morbidity, radiation exposure and financial burden. None of these imaging strategies is universally accepted. The"top-down approach" (TDA) aims at restricting the number of voiding cystourethrograms (VCUGs) and its associated morbidity while identifying patients with clinically-significant reflux. In this approach, children presenting with febrile UTIs are acutely investigated with dimercapto-succinic acid (DMSA) renal scans to identify patients with renal parenchymal inflammation. Those with evidence of renal affection are offered VCUG and late DMSA scan to identify VUR and permanent renal scarring, respectively. Although TDA could identify clinically-significant VUR with high sensitivity, it is not without limitations. The approach segregates patients based on the presence of DMSA cortical lesions omitting the morbidity and the economic burden of UTI. Additionally, some of DMSA lesions are attributed to congenital dysplasia and unrelated to UTI. Ionizing radiation exposure, financial costs, limited availability of DMSA scans in the acute setting, variability in interpreting the results and low yield of actionable findings on DMSA scans are some other limitations. In this review, we tried to address the drawbacks of the TDA and reinforce the value of patient-centered approach for VUR.

Critical appraisal of the top-down approach for vesicoureteral reflux

PubMed Central

Abdelhalim, Ahmed

2017-01-01

Vesicoureteral reflux (VUR) has been linked to recurrent urinary tract infections (UTIs), renal scarring, hypertension, renal insufficiency and end-stage kidney disease. Different imaging strategies have been proposed to approach children presenting with UTI to sort out patients with significant VUR while minimizing patient morbidity, radiation exposure and financial burden. None of these imaging strategies is universally accepted. The“top-down approach” (TDA) aims at restricting the number of voiding cystourethrograms (VCUGs) and its associated morbidity while identifying patients with clinically-significant reflux. In this approach, children presenting with febrile UTIs are acutely investigated with dimercapto-succinic acid (DMSA) renal scans to identify patients with renal parenchymal inflammation. Those with evidence of renal affection are offered VCUG and late DMSA scan to identify VUR and permanent renal scarring, respectively. Although TDA could identify clinically-significant VUR with high sensitivity, it is not without limitations. The approach segregates patients based on the presence of DMSA cortical lesions omitting the morbidity and the economic burden of UTI. Additionally, some of DMSA lesions are attributed to congenital dysplasia and unrelated to UTI. Ionizing radiation exposure, financial costs, limited availability of DMSA scans in the acute setting, variability in interpreting the results and low yield of actionable findings on DMSA scans are some other limitations. In this review, we tried to address the drawbacks of the TDA and reinforce the value of patient-centered approach for VUR. PMID:28612056

Automatic classification of DMSA scans using an artificial neural network

NASA Astrophysics Data System (ADS)

Wright, J. W.; Duguid, R.; Mckiddie, F.; Staff, R. T.

2014-04-01

DMSA imaging is carried out in nuclear medicine to assess the level of functional renal tissue in patients. This study investigated the use of an artificial neural network to perform diagnostic classification of these scans. Using the radiological report as the gold standard, the network was trained to classify DMSA scans as positive or negative for defects using a representative sample of 257 previously reported images. The trained network was then independently tested using a further 193 scans and achieved a binary classification accuracy of 95.9%. The performance of the network was compared with three qualified expert observers who were asked to grade each scan in the 193 image testing set on a six point defect scale, from ‘definitely normal’ to ‘definitely abnormal’. A receiver operating characteristic analysis comparison between a consensus operator, generated from the scores of the three expert observers, and the network revealed a statistically significant increase (α < 0.05) in performance between the network and operators. A further result from this work was that when suitably optimized, a negative predictive value of 100% for renal defects was achieved by the network, while still managing to identify 93% of the negative cases in the dataset. These results are encouraging for application of such a network as a screening tool or quality assurance assistant in clinical practice.

Images of liposarcoma using technetium-99m bleomycin and technetium (V)-99m DMSA

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

Ohta, H.; Shane, F.I.; Endo, K.

1986-12-01

The effectiveness of Tc-99m bleomycin (BLM) and Tc(V)-99m DMSA are compared with that of Ga-67 citrate, which is currently the most widely used agent. In four patients with lipomatous tumors, the clinical significance of tumor imaging with each of these three agents is discussed and compared. Results indicate that both Tc-99m BLM and Tc(V)-99m DMSA are superior in detecting the extension or localization of liposarcomas.

Naturally-Occurring DMSP Analogs as Potential Precursors of Dimethyl Sulfide (DMS) and Methanethiol (MeSH) in Coastal Seawater

NASA Astrophysics Data System (ADS)

Cordero, D.; Kiene, R. P.

2016-02-01

Dimethylsulfoniopropionate (DMSP) is an osmolyte produced by various macroalgae and phytoplankton in the marine environment. DMSP is known to be the main precursor for dimethyl sulfide (DMS), the major natural sulfur gas emitted from the oceans to the atmosphere. DMS contributes to formation and growth of sulfur-containing aerosols in our stratosphere. These aerosols influence Earth's solar radiation balance and potentially affect the formation of clouds, which could function as a counter-effect to global warming. Bacterioplankton are capable of converting DMSP into DMS via the enzyme DMSP lyase. But not all DMSP in the ocean is converted into DMS. A significant fraction of the DMSP available in the ocean is converted to methanethiol (MeSH) via the bacterial demethylation/demethiolation pathway, with a portion of the MeSH being assimilated as both a carbon and sulfur source. Here we test whether several other naturally-occurring dimethyl sulfonium compounds could be precursors of DMS and MeSH. To test this, we carried out experiments with estuarine water samples from Mobile Bay in the Northern Gulf of Mexico. After collection, unfiltered seawater and seawater filtrate samples, the later containing bacteria only, were treated with 50 nM additions of either 2-dimethylsulfononioacetate (DMSA) or S-Methylmethionine (SMM). After addition of the dimethyl sulfonium compounds, samples were analyzed for sulfur gases with Gas Chromatography-Flame Photometric Detection, using cryogenic-trapping techniques. Addition of DMSA resulted in an immediate increase in MeSH production in both seawater and seawater filtrate containing bacteria only, producing even more MeSH than DMSP. This suggests that DMSA is potentially a significant precursor for MeSH. DMS was not produced in significant amounts from DMSA. Addition of SMM resulted in low rates of both DMS and MeSH accumulation in both seawater samples, indicating that SMM may be a minor precursor for both gases compared to DMSP.

Effects of coating molecules on the magnetic heating properties of Au-Fe3O4 heterodimer nanoparticles

NASA Astrophysics Data System (ADS)

Yamamoto, Y.; Ogasawara, J.; Himukai, H.; Itoh, T.

2016-10-01

In this paper, we report the heating properties of gold-magnetite (Au-Fe3O4) heterodimer nanoparticles (NPs) subjected to an alternating magnetic field. The Au-Fe3O4 NPs coated with oleic acid and oleylamine (OA) were synthesized through a method that combines seed mediation and high-temperature decomposition. The coating was replaced with dimercaptosuccinic acid (DMSA) by the ligand-exchange method. The specific absorption rates (SARs) for the OA- and DMSA-coated Au-Fe3O4 NPs coated with OA and DMSA at room temperature were determined through the calorimetric and magnetometric methods. SAR depended on the square of the magnetic field H up to an H value of 4 kA/m. The absolute value of the SAR for DMSA-coated NPs is about fivefold higher than that of the OA-coated NPs. The AC magnetic hysteresis measurements showed the recovery of the magnetic volume and the decrease in the magnetic anisotropy of the DMSA-coated NPs relative to those of the OA-coated NPs. These results suggest that the protective agent influences the magnetic properties of magnetite NPs via gold NPs.

The adaptive approach for storage assignment by mining data of warehouse management system for distribution centres

NASA Astrophysics Data System (ADS)

Ming-Huang Chiang, David; Lin, Chia-Ping; Chen, Mu-Chen

2011-05-01

Among distribution centre operations, order picking has been reported to be the most labour-intensive activity. Sophisticated storage assignment policies adopted to reduce the travel distance of order picking have been explored in the literature. Unfortunately, previous research has been devoted to locating entire products from scratch. Instead, this study intends to propose an adaptive approach, a Data Mining-based Storage Assignment approach (DMSA), to find the optimal storage assignment for newly delivered products that need to be put away when there is vacant shelf space in a distribution centre. In the DMSA, a new association index (AIX) is developed to evaluate the fitness between the put away products and the unassigned storage locations by applying association rule mining. With AIX, the storage location assignment problem (SLAP) can be formulated and solved as a binary integer programming. To evaluate the performance of DMSA, a real-world order database of a distribution centre is obtained and used to compare the results from DMSA with a random assignment approach. It turns out that DMSA outperforms random assignment as the number of put away products and the proportion of put away products with high turnover rates increase.

Identifying Vulnerable Atherosclerotic Plaque in Rabbits Using DMSA-USPIO Enhanced Magnetic Resonance Imaging to Investigate the Effect of Atorvastatin

PubMed Central

Li, Dongye; Wu, Weiheng; Gong, Lei; Li, Yong; Zhang, Qingdui; Zhang, Tao; Zhang, Chao; Zhang, Yu

2015-01-01

Background Rupture of an atherosclerotic plaque is the primary cause of acute cardiovascular and cerebrovascular syndromes. Early and non-invasive detection of vulnerable atherosclerotic plaques (VP) would be significant in preventing some aspects of these syndromes. As a new contrast agent, dimercaptosuccinic acid (DMSA) modified ultra-small super paramagnetic iron oxide (USPIO) was synthesized and used to identify VP and rupture plaque by magnetic resonance imaging (MRI). Methods Atherosclerosis was induced in male New Zealand White rabbits by feeding a high cholesterol diet (n = 30). Group A with atherosclerosis plaque (n = 10) were controls. VP was established in groups B (n = 10) and C (n = 10) using balloon-induced endothelial injury of the abdominal aorta. Adenovirus-carrying p53 genes were injected into the aortic segments rich in plaques after 8 weeks. Group C was treated with atorvastatin for 8 weeks. Sixteen weeks later, all rabbits underwent pharmacological triggering, and imaging were taken daily for 5 d after DMSA-USPIO infusion. At the first day and before being killed, serum MMP-9, sCD40L, and other lipid indicators were measured. Results DMSA-USPIO particles accumulated in VP and rupture plaques. Rupture plaques appeared as areas of hyper-intensity on DMSA-USPIO enhanced MRI, especially T2*-weighted sequences, with a signal strength peaking at 96 h. The group given atorvastatin showed few DMSA-USPIO particles and had lower levels of serum indicators. MMP-9 and sCD40L levels in group B were significantly higher than in the other 2 groups (P <0.05). Conclusion After successfully establishing a VP model in rabbits, DMSA-USPIO was used to enhance MRI for clear identification of plaque inflammation and rupture. Rupture plaques were detectable in this way probably due to an activating inflammatory process. Atorvastatin reduced the inflammatory response and stabilizing VP possibly by decreasing MMP-9 and sCD40L levels. PMID:25973795

Delayed treatment of the first febrile urinary tract infection in early childhood increased the risk of renal scarring.

PubMed

Karavanaki, Kyriaki A; Soldatou, Alexandra; Koufadaki, Athina Maria; Tsentidis, Charalampos; Haliotis, Fotis A; Stefanidis, Constantinos J

2017-01-01

This study evaluated the controversial relationship between the duration of fever before treatment initiation (FBT) for a febrile urinary tract infection (UTI), with renal scarring based on dimercaptosuccinic acid scintigraphy (DMSA) findings. The inpatient records of 148 children under two years of age with a first episode of febrile UTI were analysed. Acute and repeat DMSA findings, and clinical and laboratory parameters were evaluated. Acute DMSA showed that 76 of the 148 children with a febrile UTI had renal lesions: 20 were mild, and 56 were moderate or severe. Repeat DMSA showed renal scarring in 34 patients. The only factors associated with the development of renal scars in the repeat DMSA were FBT of more than 72 hours, the presence and severity of vesicoureteral reflux and increased procalcitonin levels and absolute neutrophil counts. Multiple regression analysis showed that an FBT above 72 hours was the only significant factor that predicted renal scars. Delay in treatment initiation of 72 hours or more was a risk factor for permanent renal scars after the first episode of febrile UTI. Other associated factors were increased procalcitonin and absolute neutrophil count on admission and the presence and severity of vesicouretal reflux. ©2016 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

[Antagonism of total flavonoids from Chrysanthemum morifolium against lead induced oxidative injury in mice].

PubMed

Xia, Dao-zong; Lv, Gui-yuan; Yu, Xin-fens; Wang, Hui-ming; Yang, Qing

2008-12-01

To investigate antagonism effects of total flavonoids from Chrysanthemum morifolium. (TFCM) against lead induced oxidative injury. Ninety male mice were randomly divided into 9 groups. Mice except normal control group inject lead acetate every other day for 20 days. In the next 10 d, drugs were orally administrated to mice once a day. After the last aministration, mice were sacrificed and immediately subjected to necropsy. The concentration of lead, zinc and copper in blood, brain, liver and kidney were determined. The body weight, relative organ weight, antioxidant enzyme levels (GSH, GSH-Px, SOD and CAT) and lipid peroxidation products (MDA) were performed. TFCM might antagonize the decrease of body weight and the increase of organ weight/body weight ratio. The combined treatment with TFCM and DMSA can significantly lower the lead levels in blood, brain, liver and kidney. In contrast, lead concentration in mice treated with TFCM alone did not show significant change in these organs. The other trace elements such as zinc and copper had no significant decrease after TFCM or DMSA treatment. Middle and high-dose TFCM was more effective than DMSA in increasing the activity of GSH, GSH-Px, SOD, CAT and decreasing the concentration of MDA in mice brain. In addition, high-dose TFCM was more effective than DMSA in increasing the activity of GSH-Px, CAT and decreasing the concentration of MDA in mice liver and kidney. The combined treatment with TFCM and DMSA also can reverse lipid peroxidation and increase antioxidant enzyme levels in lead poisoning mice dose-dependently, and it had more beneficial effects than treatment with DMSA alone. TFCM might improve antioxidant defense system, reverse lipid peroxidation and protect brain, liver and kidney against lead induced oxidative damage in mice significantly.

EFFECT OF DMPS AND DMSA ON THE PLACENTAL AND FETAL DISPOSITION OF METHYLMERCURY

PubMed Central

Bridges, Christy C.; Joshee, Lucy; Zalups, Rudolfs K.

2009-01-01

Methylmercury (CH3Hg+) is a serious environmental toxicant. Exposure to this metal during pregnancy can cause serious neurological and developmental defects in a developing fetus. Surprisingly, little is known about the mechanisms by which mercuric ions are transported across the placenta. Although it has been shown that 2,3-dimercaptopropane-1-sulfonate (DMPS) and 2,3-dimercaptosuccinic acid (DMSA) are capable of extracting mercuric ions from various organs and cells, there is no evidence that they are able to extract mercury from placental or fetal tissues following maternal exposure to CH3Hg+. Therefore, the purpose of the current study was to evaluate the ability of DMPS and DMSA to extract mercuric ions from placental and fetal tissues following maternal exposure to CH3Hg+. Pregnant Wistar rats were exposed to CH3HgCl, containing [203Hg], on day 11 or day 17 of pregnancy and treated 24 h later with saline, DMPS or DMSA. Maternal organs, fetuses, and placentas were harvested 48 h after exposure to CH3HgCl. The disposition of mercuric ions in maternal organs and tissues was similar to that reported previously by our laboratory. The disposition of mercuric ions in placentas and fetuses appeared to be dependent upon the gestational age of the fetus. The fetal and placental burden of mercury increased as fetal age increased and was reduced by DMPS and DMSA, with DMPS being more effective. The disposition of mercury was examined in liver, total renal mass, and brain of fetuses harvested on gestational day 19. On a per gram tissue basis, the greatest amount of mercury was detected in the total renal mass of the fetus, followed by brain and liver. DMPS and DMSA reduced the burden of mercury in liver and brain while only DMPS was effective in the total renal mass. The results of the current study are the first to show that DMPS and DMSA are capable of extracting mercuric ions, not only from maternal tissues, but also from placental and fetal tissues following maternal exposure to CH3Hg+. PMID:19615742

Topical efficacy of dimercapto-chelating agents against lewisite-induced skin lesions in SKH-1 hairless mice

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

Mouret, Stéphane, E-mail: stephane.mouret@irba.fr; Wartelle, Julien; Emorine, Sandy

2013-10-15

Lewisite is a potent chemical warfare arsenical vesicant that can cause severe skin lesions. Today, lewisite exposure remains possible during demilitarization of old ammunitions and as a result of deliberate use. Although its cutaneous toxicity is not fully elucidated, a specific antidote exists, the British anti-lewisite (BAL, dimercaprol) but it is not without untoward effects. Analogs of BAL, less toxic, have been developed such as meso-2,3-dimercaptosuccinic acid (DMSA) and have been employed for the treatment of heavy metal poisoning. However, efficacy of DMSA against lewisite-induced skin lesions remains to be determined in comparison with BAL. We have thus evaluated inmore » this study the therapeutic efficacy of BAL and DMSA in two administration modes against skin lesions induced by lewisite vapor on SKH-1 hairless mice. Our data demonstrate a strong protective efficacy of topical application of dimercapto-chelating agents in contrast to a subcutaneous administration 1 h after lewisite exposure, with attenuation of wound size, necrosis and impairment of skin barrier function. The histological evaluation also confirms the efficacy of topical application by showing that treatments were effective in reversing lewisite-induced neutrophil infiltration. This protective effect was associated with an epidermal hyperplasia. However, for all the parameters studied, BAL was more effective than DMSA in reducing lewisite-induced skin injury. Together, these findings support the use of a topical form of dimercaprol-chelating agent against lewisite-induced skin lesion within the first hour after exposure to increase the therapeutic management and that BAL, despite its side-effects, should not be abandoned. - Highlights: • Topically applied dimercapto-chelating agents reduce lewisite-induced skin damage. • One topical application of BAL or DMSA is sufficient to reverse lewisite effects. • Topical BAL is more effective than DMSA to counteract lewisite-induced skin damage.« less

Acoustic radiation force impulse (ARFI) elastography for detection of renal damage in children.

PubMed

Göya, Cemil; Hamidi, Cihad; Ece, Aydın; Okur, Mehmet Hanifi; Taşdemir, Bekir; Çetinçakmak, Mehmet Güli; Hattapoğlu, Salih; Teke, Memik; Şahin, Cahit

2015-01-01

Acoustic radiation force impulse (ARFI) imaging is a promising method for noninvasive evaluation of the renal parenchyma. To investigate the contribution of ARFI quantitative US elastography for the detection of renal damage in kidneys with and without vesicoureteral reflux (VUR). One hundred seventy-six kidneys of 88 children (46 male, 42 female) who had been referred for voiding cystourethrography and 20 healthy controls were prospectively investigated. Patients were assessed according to severity of renal damage on dimercaptosuccinic acid (DMSA) scintigraphy. Ninety-eight age- and gender-matched healthy children constituted the control group. Quantitative shear wave velocity (SWV) measurements were performed in the upper and lower poles and in the interpolar region of each kidney. DMSA scintigraphy was performed in 62 children (124 kidneys). Comparisons of SWV values of kidneys with and without renal damage and/or VUR were done. Significantly higher SWV values were found in non-damaged kidneys. Severely damaged kidneys had the lowest SWV values (P < 0.001). High-grade (grade V-IV) refluxing kidneys had the lowest SWV values, while non-refluxing kidneys had the highest values (P < 0.05). Significant negative correlations were found between the mean quantitative US elastography values and DMSA scarring score (r = -0.788, P < 0.001) and VUR grade (r = -0.634, P < 0.001). SWV values of the control kidneys were significantly higher than those of damaged kidneys (P < 0.05). Our findings suggest decreasing SWV of renal units with increasing grades of vesicoureteric reflux, increasing DMSA-assessed renal damage and decreasing DMSA-assessed differential function.

99mTc-DMSA Uptake in a Sister Mary Joseph's Nodule From Ovarian Cancer.

PubMed

Naddaf, Sleiman; Azzumeea, Fahad; Fahad Alzayed, Mohammed

2016-12-01

A 50-year-old woman with ovarian cancer underwent Tc-DMSA scan to evaluate the functional status of the right hydronephrotic kidney. The images incidentally revealed a well-defined focus of mild radiotracer uptake at the midanterior abdominal wall, which correlated with a metastatic Sister Mary Joseph's nodule seen on CT performed a week earlier.

Urinary 8-hydroxy-2'-deoxyguanosine (8-oxodG) level can predict acute renal damage in young children with urinary tract infection.

PubMed

Chien, Jien-Wen; Wang, Lien-Yen; Cheng, Yu-Shan; Tsai, Yi-Giien; Liu, Chin-San

2014-06-01

There are no good biomarkers to predict renal parenchymal involvement in children with urinary tract infection (UTI). Children (N = 73) younger than 5 years with UTI were enrolled. Urinary levels of 8-hydroxy-2'-deoxyguanosine (8-oxodG) and total antioxidant capacity (TAC) were checked as markers of oxidative stress and antioxidant capacity, respectively. Tc99m-dimercaptosuccinic acid (DMSA) renal scintigraphy was used to find evidence of renal involvement. Patients with positive DMSA findings had higher levels of urinary 8-oxodG (p = 0.003) and higher urinary TAC (p = 0.001) than patients with normal DMSA findings. High level of urinary 8-oxodG may be a risk factor of severe renal damage.

Magnetic hyperthermia and pH-responsive effective drug delivery to the sub-cellular level of human breast cancer cells by modified CoFe2O4 nanoparticles.

PubMed

Oh, Yunok; Moorthy, Madhappan Santha; Manivasagan, Panchanathan; Bharathiraja, Subramaniyan; Oh, Junghwan

2017-02-01

Magnetic iron oxide nanoparticles (MNPs) have been extensively utilized in a wide range of biomedical applications including magnetic hyperthermia agent. To improve the efficiency of the MNPs in therapeutic applications, in this study, we have synthesized CoFe 2 O 4 nanoparticles and its surface was further functionalized with meso-2,3-dimercaptosuccinic acid (DMSA). The anticancer agent, Doxorubucin (DOX) was conjugated with CoFe 2 O 4 @DMSA nanoparticle to evaluate the combined effects of thermotherapy and chemotherapy. The drug delivery efficiency of the DOX loaded CoFe 2 O 4 @DMSA nanoparticles were examined based on magnetically triggered delivery of DOX into the subcellular level of cancer cells by using MDA-MB-231 cell line. The amine part of the DOX molecules were effectively attached through an electrostatic interactions and/or hydrogen bonding interactions with the carboxylic acid groups of the DMSA functionalities present onto the surface of the CoFe 2 O 4 nanoparticles. The DOX loaded CoFe 2 O 4 @DMSA nanoparticles can effectively uptake with cancer cells via typical endocytosis process. After endocytosis, DOX release from CoFe 2 O 4 nanoparticles was triggered by intracellular endosomal/lysosomal acidic environments and the localized heat can be generated under an alternating magnetic field (AMF). In the presence of AMF, the released DOX molecules were accumulated with high concentrations into the subcellular level at a desired sites and exhibited a synergistic effect of an enhanced cell cytotoxicity by the combined effects of thermal-chemotherapy. Importantly, pH- and thermal-responsive Dox-loaded CoFe 2 O 4 nanoparticles induced significant cellular apoptosis more efficiently mediated by active mitochondrial membrane and ROS generation than the free Dox. Thus, the Dox-loaded CoFe 2 O 4 @DMSA nanoparticles can be used as a potential therapeutic agent in cancer therapy by combining the thermo-chemotherapy techniques. Copyright © 2016. Published by Elsevier B.V.

Usefulness of analytical parameters in the management of paediatric patients with suspicion of acute pyelonephritis. Is procalcitonin reliable?

PubMed

Bañuelos-Andrío, L; Espino-Hernández, M; Ruperez-Lucas, M; Villar-Del Campo, M C; Romero-Carrasco, C I; Rodríguez-Caravaca, G

To investigate the usefulness of procalcitonin (PCT) and other analytical parameters (white blood cell count [WBC], C-reactive protein [CRP]) as markers of acute renal damage in children after a first febrile or afebrile urinary tract infection (UTI). A retrospective study was conducted on children with a first episode of UTI admitted between January 2009 to December 2011, and in whom serum PCT, CRP and white blood cell count were measured, as well as assessing the acute renal damage with renal scintigraphy with 99m Tc-DMSA (DMSA) within the first 72h after referral. A descriptive study was performed and ROC curves were plotted, with optimal cut-off points calculated for each parameter. The 101 enrolled patients were divided into two groups according to DMSA scintigraphy results, with 64 patients being classified with acute pyelonephritis (APN), and 37 with UTI. The mean WBC, CRP and PCT values were significantly higher in patients with APN with respect to normal acute DMSA. The area under the ROC curve was 0.862 for PCR, 0.774 for WBC, and 0.731 for PCT. The optimum statistical cut-off value for PCT was 0.285ng/ml (sensitivity 71.4% and specificity 75%). Although the mean levels of fever, WBC, CRP, and PCT were significantly increased in patients with APN than in those who had UTI, the sensitivity and specificity of these analytical parameters are unable to predict the existence of acute renal damage, making the contribution by renal DMSA scintigraphy essential. Copyright © 2016 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

A cluster of pediatric metallic mercury exposure cases treated with meso-2,3-dimercaptosuccinic acid (DMSA)

PubMed Central

Forman, J; Moline, J; Cernichiari, E; Sayegh, S; Torres, J C; Landrigan, M M; Hudson, J; Adel, H N; Landrigan, P J

2000-01-01

Nine children and their mother were exposed to vapors of metallic mercury. The source of the exposure appears to have been a 6-oz vial of mercury taken from a neighbor's home. The neighbor reportedly operated a business preparing mercury-filled amulets for practitioners of the Afro-Caribbean religion Santeria. At diagnosis, urinary mercury levels in the children ranged from 61 to 1,213 microg/g creatinine, with a geometric mean of 214.3 microg/m creatinine. All of the children were asymptomatic. To prevent development of neurotoxicity, we treated the children with oral meso-2,3-dimercaptosuccinic acid (DMSA). During chelation, the geometric mean urine level rose initially by 268% to 573.2 microg mercury/g creatinine (p<0.0005). At the 6-week follow-up examination after treatment, the geometric mean urine mercury level had fallen to 102.1 microg/g creatinine, which was 17.8% of the geometric mean level observed during treatment (p<0.0005) and 47.6% of the original baseline level (p<0.001). Thus, oral chelation with DMSA produced a significant mercury diuresis in these children. We observed no adverse side effects of treatment. DMSA appears to be an effective and safe chelating agent for treatment of pediatric overexposure to metallic mercury. Images Figure 1 PMID:10856034

Electroanalytical and isothermal calorimetric study of As(III) complexation by the metal poisoning remediators, 2,3-dimercapto-1-propanesulfonate and meso-2,3-dimercaptosuccinic acid.

PubMed

Cavanillas, Santiago; Chekmeneva, Elena; Ariño, Cristina; Díaz-Cruz, José Manuel; Esteban, Miquel

2012-10-09

A recently developed methodology, which combines voltammetry, ITC, ESI-MS and several chemometric tools, has been applied for the first time to the study of As(III) complexes. The ligands considered, DMSA and DMPS, are commonly used to treat heavy metal poisoning. The study yields a reliable and consistent picture of the binding of As(III) by the chelating therapy agents DMSA and DMPS providing an unambiguous description of the stoichiometries of the complexes (ML(2), with the occasional appearance of ML in the case of DMSA), both ligands have stability constants of the same order, with a logβ(2) of 9.2 and 9.8, respectively. These values confirm the potential efficiency of both ligands in the treatment of As(III) poisoning. Copyright © 2012 Elsevier B.V. All rights reserved.

Correction of differential renal function for asymmetric renal area ratio in unilateral hydronephrosis.

PubMed

Aktaş, Gul Ege; Sarıkaya, Ali

2015-11-01

Children with unilateral hydronephrosis are followed up with anteroposterior pelvic diameter (APD), hydronephrosis grade, mercaptoacetyltriglycine (MAG-3) drainage pattern and differential renal function (DRF). Indeterminate drainage preserved DRF in higher grades of hydronephrosis, in some situations, complicating the decision-making process. Due to an asymmetric renal area ratio, falsely negative DRF estimations can result in missed optimal surgery times. This study was designed to assess whether correcting the DRF estimation according to kidney area could reflect the clinical situation of a hydronephrotic kidney better than a classical DRF calculation, concurrently with the hydronephrosis grade, APD and MAG-3 drainage pattern. We reviewed the MAG-3, dimercaptosuccinic acid (DMSA) scans and ultrasonography (US) of 23 children (6 girls, 17 boys, mean age: 29 ± 50 months) with unilateral hydronephrosis. MAG-3 and DMSA scans were performed within 3 months (mean 25.4 ± 30.7 days). The closest US findings (mean 41.5 ± 28.2 days) were used. DMSA DRF estimations were obtained using the geometric mean method. Secondary calculations were performed to correct the counts (the total counts divided by the number of pixels in ROI) according to kidney area. The renogram patterns of patients were evaluated and separated into subgroups. The visual assessment of DMSA scans was noted and the hydronephrotic kidney was classified in comparison to the normal contralateral kidney's uptake. The correlations of the DRF values of classical and area-corrected methods with MAG-3 renogram patterns, the visual classification of DMSA scan, the hydronephrosis grade and the APD were assessed. DRF estimations of two methods were statistically different (p: 0.001). The categories of 12 hydronephrotic kidneys were changed. There were no correlations between classical DRF estimations and the hydronephrosis grade, APD, visual classification of the DMSA scan and uptake evaluation. The DRF distributions according to MAG-3 drainage patterns were not different. Area-corrected DRF estimations correlated with all: with an increasing hydronephrosis grade and APD, DRF estimations decreased and MAG-3 drainage patterns worsened. A decrease in DRF (< 45 %) was determined when APD was ≥ 10 mm. When APD was ≥ 26 mm, a reduction of DRF below 40 % was determined. Our results suggest that correcting DRF estimation for asymmetric renal area ratio in unilateral hydronephrosis can be more robust than the classical method, especially for higher grades of hydronephrotic kidneys, under equivocal circumstances.

'Targeted top down' approach for the investigation of UTI: A 10-year follow-up study in a cohort of 1000 children.

PubMed

Broadis, E; Kronfli, R; Flett, M E; Cascio, S; O'Toole, S J

2016-02-01

Investigations following urinary tract infection (UTI) aim to identify children who are prone to renal scarring, which may be preventable. In 2002, in an attempt to reduce unnecessary intervention, the present institution standardised the investigation of children with a confirmed UTI. This study aimed to identify the significance of urological abnormalities on investigations following a UTI in children, prior to the introduction of the National Institute for Health and Care Excellence (NICE) guidelines. Clinical information on the first 1000 patients was retrieved from a prospective UTI hospital database. The follow-up period was 10 years. There were 180 males and 820 females (M:F = 1:4.5). The median age of presentation was 5 years (range 11 days-16 years). A renal ultrasound (US) was performed on all patients, and was normal in 93% of cases (n = 889) (see Figure). Of the 7% who had an abnormal US (n = 71), 54 were female and 17 male (M:F = 1:3). A total of 372 DMSA scans were requested and 350 attended their appointment. Of these, 278 cases (79%) were reported as normal, while 72 had an abnormality documented. Of these 72 patients with abnormalities on DMSA scan, 49 had a repeat DMSA scan: 30 demonstrated permanent scarring, while the DMSA scan became normal in 19. Sixteen of the 278 patients whose DMSA scan was initially normal had a repeat DMSA scan due to symptoms, and all scans were normal. Twelve (1.2%) patients required surgical intervention: three underwent circumcision for recurrent UTIs; three underwent endoscopic treatment of VUR; one had a PUV resection; one underwent a cystoscopy; three had a pyeloplasty for pelvi-ureteric junction obstruction; and one had a ureteric reimplantation for vesico-ureteric junction obstruction. After initial investigations and management, 936 patients were discharged from the UTI clinic: 47 of them re-presented - 40 with recurrent UTIs and seven with dysuria. Thirty-five of the 47 children who re-presented with urological symptoms underwent a DMSA scan, which showed scarring in three (6%). Only 12% of children have a significant radiological abnormality picked up on investigation following a UTI. The present investigation approach differed from the NICE guidelines, where imaging is based on patient age and characteristics of the UTI. All children had a renal US, while DMSA scans were reserved for those children <1 year of age or those with upper tract symptoms. The present protocol recommended a renal US in all children presenting with a UTI. This promptly identified those with pelvi-ureteric junction obstruction and those with PUV, who all presented >6 months of age with a single UTI and, therefore, based on the NICE guidelines would not have undergone a renal US. Of the children who re-presented with further UTIs, a significant number were found to have dysfunctional voiding. As this link is well reported, it may be appropriate to screen for this in older children at initial presentation. Only three patients, who had a US at presentation, were subsequently found to have scarring on DMSA. After 10 years of follow-up, this could represent a false negative rate of 0.3% for the screening programme. None of the girls were found to have VUR or needed any surgical intervention, which suggested that early identification of the scarring might not have altered management. Few patients required surgical intervention, all of whom were identified early. No patient who re-presented required intervention. This would suggest that the present protocol is effective at picking up abnormalities that require surgical management. This study suggested that after a childhood UTI, the liberal use of renal ultrasound and a focused 'top down' approach to investigation is likely to identify the vast majority of children who require intervention. Copyright © 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

The study of the changes in the biochemical and mineral contents of bones of Catla catla due to lead intoxication.

PubMed

Palaniappan, P L R M; Krishnakumar, N; Vadivelu, M; Vijayasundaram, V

2010-02-01

In the present study, an attempt has been made to analyze the changes in the biochemical and mineral contents of lead-intoxicated bones of Catla catla at subchronic (15.5 ppm) exposure, and also to determine whether the effects of Pb intoxication can be reversed with the chelating agent meso 2, 3-dimercaptosuccinic acid (DMSA) on the bones of freshwater fingerlings Catla catla by using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and atomic absorption spectrophotometer techniques. The FT-IR spectra of the lead-exposed bones show significant alteration in the biochemical constituents. The XRD analysis showed a decrease in crystallinity due to lead exposure. Further, the Ca, Mg, and P contents of the lead-exposed bones were less than those of the control group, and there was an increase in the mineral contents of the bones after DMSA treatment. In conclusion, the present study suggests that the subchronic lead exposure results in severe loss of bone minerals. The overall decrease in the FT-IR band intensity of Pb-exposed bones relative to the control indicates a decrease in the biochemical constituents like proteins and lipids. The increase in the band intensity after treatment with chelating agent DMSA indicates increased biochemical constituents, showing that the subchronic effects of lead can be reversed by DMSA. The amide I bands observed at 1654 cm(-1) in the present study suggest that the protein is dominated by alpha-helical structure.

[Lead intoxication in a group of workers in Germany].

PubMed

Willi, R F; Felgenhauer, N; Eyer, F; Buters, J T; Zilker, T

2009-12-01

Seventeen East-European workers with a suspected lead-intoxication presented themselves to the Department of Toxicology. All of them had worked on the renovation of pylons of a high-tension line. The old paint, known to contain lead was removed with needle descalers. The patients had blood lead concentrations between 325 and 1124 microg/l, but no specific symptoms. The workers neglected the protective measures at their working-place. 12 of 17 workers had lead-concentrations above 400 microg/l (Reference < 90 microg/l). 10 of 17 patients showed an increased level of free protoporphyrins and all workers showed a decreased activity of delta-aminolaevulinacid-dehydratase (ALAD). Patients with lead-concentration above 700 microg/l were treated with the chelating agent meso-2,3-dimercaptosuccinic acid (DMSA) 3 x 200 mg/d for nine days. The patients with lead concentrations between 400 and 700 microg/l were treated which DMSA 3 x 100 mg/d. After the DMSA-treatment the lead-concentrations had dropped (p < 0.001). During the DMSA-therapy one patient had to be treated in the hospital because of a generalised allergic exanthema. We report seventeen patients with high lead concentration in their blood due to occupational exposure. The high blood lead levels showed that the workers had not been protected adequately. This examplifies that occupational lead exposure still occurs, also in Germany. By patients with unspecific symptoms connected with lead exposure a biomonitoring for lead is necessary.

Evaluation of the protective effect of agmatine against cisplatin nephrotoxicity with 99mTc-DMSA renal scintigraphy and cystatin-C.

PubMed

Salihoglu, Yavuz Sami; Elri, Tarik; Gulle, Kanat; Can, Murat; Aras, Mustafa; Ozacmak, Hale Sayan; Cabuk, Mehmet

2016-10-01

The aim of the current study was to investigate whether agmatine (AGM) has a protective effect against cisplatin-induced nephrotoxicity. Thirty-two rats were randomly divided into four groups: (1) Saline (control); (2) Cisplatin (CDDP; 7.5 mg/kg intraperitoneally); (3) Agmatine (AGM; 10 mg/kg intraperitoneally); (4) Cisplatin plus agmatine (CDDP + AGM). Agmatine was given before and two consecutive days after cisplatin injection. All the animals underwent renal scintigraphy with 99mTc-DMSA. The levels of serum creatinine, cystatin C, and blood urea nitrogen (BUN) were measured in addition to examination of the tissue samples with light microscopy. Acute renal injury was assessed with biochemical analyses, scintigraphic imaging, and histopathological evaluation. In the cisplatin group, the levels of BUN, creatinine, and cystatin C were significantly higher than that of the controls. Histopathological examination showed remarkable damage of tubular and glomerular structures. Additionally, cisplatin caused markedly decreased renal 99mTc-DMSA uptake. AGM administration improved renal functions. Serum creatinine, BUN, and cystatin C levels had a tendency to normalize and, scintigraphic and histopathological findings showed significantly less evidence of renal toxicity than those observed in animals receiving cisplatin alone. Our data indicate that AGM has a protective effect against cisplatin-induced nephrotoxicity. Therefore, it may improve the therapeutic index of cisplatin. In addition, the early renal damage induced by cisplatin and protective effects of AGM against cisplatin nephrotoxicity was accurately demonstrated with 99mTc-DMSA renal scintigraphy.

Case report: heavy metal burden presenting as Bartter syndrome.

PubMed

Crinnion, Walter J; Tran, Jessica Q

2010-12-01

Maternal transfer of heavy metals during fetal development or lactation possibly contributed to the clinical manifestations of Bartter syndrome and developmental delay in the offspring. An 11-month-old child diagnosed with Bartter syndrome and failure to thrive was treated concurrently for elevated metal burden while he was undergoing standard medical interventions. Treatment with body-weight doses of meso-2,3-dimercaptosuccinic acid (DMSA) reduced the body burden of lead, beryllium, copper, mercury, and cadmium at the three- and sixth-month follow-up tests. During the course of the six-month treatment, the patient gained 2.4 kg (5.2 lb) and grew approximately 9.5 cm (3.75 in). His weight shifted from significantly below the 5th percentile in weight to within the 5th percentile, and from below the 5th to within the 10th percentile for length. The child's acquisition of lead, beryllium, and copper correspond to his mother's history of stained glass assembly and occurred during fetal development or lactation, since there were no other identifiable sources that could have contributed to the heavy metal burden. Tests for known genetic mutations leading to Bartter syndrome were all negative. This case report highlights the potential benefit of DMSA for treatment of heavy metal body burden in infants who present with Bartter syndrome.

Prediction of Cortical Defect Using C-Reactive Protein and Urine Sodium to Potassium Ratio in Infants with Febrile Urinary Tract Infection

PubMed Central

Jung, Su Jin

2016-01-01

Purpose We investigated whether C-reactive protein (CRP) levels, urine protein-creatinine ratio (uProt/Cr), and urine electrolytes can be useful for discriminating acute pyelonephritis (APN) from other febrile illnesses or the presence of a cortical defect on 99mTc dimercaptosuccinic acid (DMSA) scanning (true APN) from its absence in infants with febrile urinary tract infection (UTI). Materials and Methods We examined 150 infants experiencing their first febrile UTI and 100 controls with other febrile illnesses consecutively admitted to our hospital from January 2010 to December 2012. Blood (CRP, electrolytes, Cr) and urine tests [uProt/Cr, electrolytes, and sodium-potassium ratio (uNa/K)] were performed upon admission. All infants with UTI underwent DMSA scans during admission. All data were compared between infants with UTI and controls and between infants with or without a cortical defect on DMSA scans. Using multiple logistic regression analysis, the ability of the parameters to predict true APN was analyzed. Results CRP levels and uProt/Cr were significantly higher in infants with true APN than in controls. uNa levels and uNa/K were significantly lower in infants with true APN than in controls. CRP levels and uNa/K were relevant factors for predicting true APN. The method using CRP levels, u-Prot/Cr, u-Na levels, and uNa/K had a sensitivity of 94%, specificity of 65%, positive predictive value of 60%, and negative predictive value of 95% for predicting true APN. Conclusion We conclude that these parameters are useful for discriminating APN from other febrile illnesses or discriminating true APN in infants with febrile UTI. PMID:26632389

The Effect of Ligands on FePt–Fe 3O 4 Core–Shell Magnetic Nanoparticles

DOE PAGES

Kim, Dong-Hyun; Tamada, Yoshinori; Ono, Teruo; ...

2014-03-01

FePt–Fe 3O 4 core–shell nanoparticles functionalized with 3,4-dihydroxyphenylacetic acid (DOPAC) and dimercaptosuccinic acid (DMSA) ligands were synthesized and characterized. We also found that the DOPAC ligand enhances the magnetic properties of the FePt–Fe 3O 4 particles, in comparison with the DMSA ligand, which induces the oxidation of the shell layer that causes a significant reduction of the saturation magnetization. We evaluated the synthesized magnetic nanoparticles for applications in magnetic hyperthermia and magnetic resonance imaging contrast enhancement.

Effects of meso-2,3-dimercaptosuccinic acid, potassium iodide and chlorophyll on lead accumulation in male mice.

PubMed

Xie, Ying; Zhou, Guifeng

2017-02-21

Lead (Pb) pollution is a serious public health problem all over the world, it especially plays severe damage role in children's health. Apart from reducing lead-induced damages, the decrease of lead accumulation is also critical. This study has been the first attempt to investigate effects of meso-2,3-dimercaptosuccinic acid (DMSA), potassium iodide (KI) and chlorophyll (Chl) on lead accumulation in male mice. Eighty healthy Kunming male mice were selected and divided randomly into 8 groups. They were treated with lead acetate (PbAc) intraperitoneally, individually and in combination with the DMSA, KI or Chl once daily for 5 days. Meanwhile, the control group was treated with normal saline during the whole exposure period. On 30th day, mice were sacrificed and lead concentrations were detected in the whole blood, livers, kidneys, and testicles of mice by means of the graphite furnace atomic absorption spectrometry. In comparison with the control group, lead concentrations increased in mice treated with the PbAc and DMSA, KI and Chl diminished lead accumulation in the whole blood, livers, and kidneys. Chl had specifically the same effects on lead concentrations in the testicles of male mice. Potassium iodide and Chl, as food additives, had the same effects as the DMSA to reduce lead accumulation in male mice effectively. Our results provided experimental evidence in vivo for the preventive measures of lead poisoning. Int J Occup Med Environ Health 2017;30(1):87-93. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Tc-99m Ethylenedicysteine and Tc-99m Dimercaptosuccinic Acid Scintigraphy-Comparison of the Two for Detection of Scarring and Differential Cortical Function.

PubMed

Dharmalingam, Anitha; Pawar, Shwetal U; Parelkar, Sandesh V; Shetye, Suruchi S; Ghorpade, Mangala K; Tilve, Gundu H

2017-01-01

The differential cortical function obtained by Tc-99m EC is comparable to that of Tc-99m DMSA. However, identification of scars on Tc-99m EC images needs to be studied. The aim of the study is to evaluate role of Tc-99m EC for detection of scarring and differential cortical function by comparing with Tc-99m DMSA. Prospective observational study of recurrent UTI; minimum 6 weeks after acute episode; when urine examination is negative for pus cells. Forty-seven children with normal positioned kidneys underwent Tc-99m EC and DMSA scintigraphy. The DRF and cortical phase images of both studies in the same image matrix size were evaluated by two independent observers for scarring; Tc-99m DMSA was considered as the gold standard. MS Excel 2007 and GraphPad Instat V3.1 and ROC analysis. There was no significant difference in the detection of scarring using two studies with Cohen's kappa coefficient (κ) 0.932. The sensitivity and specificity of Tc-99m EC for detection of scarring was 98.75% and 99.15%, respectively. There was good agreement between the differential cortical function calculated using two studies. The summed Tc-99m EC images with an acceptable high image contrast allow detection of cortical scarring in patients with normal kidney positions. It is an excellent single-modality comprehensive investigational agent for renal parenchymal defects, function, and excretion evaluation with the added advantages of lower cost, convenience, and low radiation exposure to the child.

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

Aburano, T.; Takayama, T.; Nakajima, K.

The three different methods to evaluate the alterations of split renal function following continued captopril treatment were studied in patients with hypertension. Five patients had unilateral and 2 had bilateral renal artery stenosis, and 13 had normal renal arteries. The studies were performed the day prior to receiving captopril (baseline), and 6th or 7th day following continued captorpril treatment (37.5mg or 75mg/day): Split effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) after injections of I-131 iodohippuran and Tc-99m DTPA were measured respectively by the methods using kidney counting corrected for depth and dose, described by Schlegel and Gates.more » And Tc-99m DMSA uptake was also evaluated qualitatively. In most of patients with renal artery stenosis, split GFR and Tc-99m DMSA uptake in the affected kidney were markedly decreased 6th or 7th day following continued captorpril treatment. These findings suggest that the captopril induced alterations of split renal function may be of importance for the diagnosis of renovascular hypertension. For this purpose, split GFR determination and Tc-99m DMSA study are more useful than split ERPF determination.« less

Description of 3,180 courses of chelation with dimercaptosuccinic acid in children ≤ 5 y with severe lead poisoning in Zamfara, Northern Nigeria: a retrospective analysis of programme data.

PubMed

Thurtle, Natalie; Greig, Jane; Cooney, Lauren; Amitai, Yona; Ariti, Cono; Brown, Mary Jean; Kosnett, Michael J; Moussally, Krystel; Sani-Gwarzo, Nasir; Akpan, Henry; Shanks, Leslie; Dargan, Paul I

2014-10-01

In 2010, Médecins Sans Frontières (MSF) discovered extensive lead poisoning impacting several thousand children in rural northern Nigeria. An estimated 400 fatalities had occurred over 3 mo. The US Centers for Disease Control and Prevention (CDC) confirmed widespread contamination from lead-rich ore being processed for gold, and environmental management was begun. MSF commenced a medical management programme that included treatment with the oral chelating agent 2,3-dimercaptosuccinic acid (DMSA, succimer). Here we describe and evaluate the changes in venous blood lead level (VBLL) associated with DMSA treatment in the largest cohort of children ≤ 5 y of age with severe paediatric lead intoxication reported to date to our knowledge. In a retrospective analysis of programme data, we describe change in VBLL after DMSA treatment courses in a cohort of 1,156 children ≤ 5 y of age who underwent between one and 15 courses of chelation treatment. Courses of DMSA of 19 or 28 d duration administered to children with VBLL ≥ 45 µg/dl were included. Impact of DMSA was calculated as end-course VBLL as a percentage of pre-course VBLL (ECP). Mixed model regression with nested random effects was used to evaluate the relative associations of covariates with ECP. Of 3,180 treatment courses administered, 36% and 6% of courses commenced with VBLL ≥ 80 µg/dl and ≥ 120 µg/dl, respectively. Overall mean ECP was 74.5% (95% CI 69.7%-79.7%); among 159 inpatient courses, ECP was 47.7% (95% CI 39.7%-57.3%). ECP after 19-d courses (n = 2,262) was lower in older children, first-ever courses, courses with a longer interval since a previous course, courses with more directly observed doses, and courses with higher pre-course VBLLs. Low haemoglobin was associated with higher ECP. Twenty children aged ≤ 5 y who commenced chelation died during the period studied, with lead poisoning a primary factor in six deaths. Monitoring of alanine transaminase (ALT), creatinine, and full blood count revealed moderate ALT elevation in <2.5% of courses. No clinically severe adverse drug effects were observed, and no laboratory findings required discontinuation of treatment. Limitations include that this was a retrospective analysis of clinical data, and unmeasured variables related to environmental exposures could not be accounted for. Oral DMSA was a pharmacodynamically effective chelating agent for the treatment of severe childhood lead poisoning in a resource-limited setting. Re-exposure to lead, despite efforts to remediate the environment, and non-adherence may have influenced the impact of outpatient treatment. Please see later in the article for the Editors' Summary.

Sectorial technetium-99m-dimercaptosuccinic acid scintigraphy for monitoring the effect of extracorporeal piezoelectric lithotripsy for calyceal calculi on regional renal function.

PubMed

Al-Tawheed, A; Al-Awadi, K A; Kehinde, E O; Loutfi, I; Abdul-Haleem, H; Al-Mohannadi, S

2003-01-01

To apply a semiquantitative method for analysis of technetium-99m-dimercaptosuccinic acid ((99m)Tc-DMSA) renal scintigraphy for monitoring the effect of extracorporeal piezoelectric lithotripsy (EPL) in patients with calyceal stones on regional kidney function and to check whether EPL had caused any deleterious effect on the target calyceal renal parenchymal function. Forty patients (mean age 35 years) suffering from calyceal stones documented by abdominal plain radiography, intravenous urogram or abdominal ultrasound were studied. All patients were treated by EPL. (99m)Tc-DMSA scan was performed before and 4 weeks after EPL. Sector analysis involved calculation of the relative function of the target calyx to the function of the ipsilateral kidney and the relative function of the treated kidney to global renal function. The stone sizes were 6-11 mm in diameter and 11 were located in the upper, 13 in the middle and 16 in the lower calyx. After EPL, the overall stone clearance rate was 85% (100% for calculi in the upper and middle calyces, 62% for lower calyces). The sector analysis did not show statistically significant change of the relative regional (calyceal) or whole kidney function between the pre- and post-EPL (99m)Tc-DMSA scans. Using sector analysis, EPL appeared to be a safe modality and its usage was not associated with any untoward effect on calyceal or whole kidney function. Sector analysis of (99m)Tc-DMSA renal scan is a simple semiquantitative method for monitoring regional changes of kidney function after EPL for treatment of calyceal stone. Copyright 2003 S. Karger AG, Basel

A study on evaluation of the dependences of the function and the shape in a 99 m Tc-DMSA renal scan on the difference in acquisition count

NASA Astrophysics Data System (ADS)

Dong, Kyung-Rae; Shim, Dong-Oh; Kim, Ho-Sung; Park, Yong-Soon; Chung, Woon-Kwan; Cho, Jae-Hwan

2013-02-01

In a nuclear medicine examination, methods to acquire a static image include the preset count method and the preset time method. The preset count method is used mainly in a static renal scan that utilizes 99 m Tc-DMSA (dimoercaptosuccinic acid) whereas the preset time method is used occasionally. When the preset count method is used, the same number of acquisition counts is acquired for each time, but the scan time varies. When the preset time method is used, the scan time is constant, but the number of counts acquired is not the same. Therefore, this study examined the dependence of the difference in information on the function and the shape of both sides of the kidneys on the counts acquired during a renal scan that utilizes 99 m Tc-DMSA. The study involved patients who had 40-60% relative function of one kidney among patients who underwent a 99 m Tc-DMSA renal scan in the Nuclear Medicine Department during the period from January 11 to March 31, 2012. A gamma camera was used to obtain the acquisition count continuously using 100,000 counts and 300,000 counts, and an acquisition time of 7 minutes (exceeding 300,000 counts). The function and the shape of the kidney were evaluated by measuring the relative function of both sides of the kidneys, the geometric mean, and the size of kidney before comparative analysis. According to the study results, neither the relative function nor the geometric mean of both sides of the kidneys varied significantly with the acquisition count. On the other hand, the size of the kidney tended to be larger with increasing acquisition count.

Accuracy of 99mTc (V)-Dimercaptosuccinic Acid Scintigraphy and Fecal Calprotectin Compared with Colonoscopy in Localizing Active Lesions in Inflammatory Bowel Disease

PubMed Central

Basirat, Vahid; Azizi, Zahra; Javid Anbardan, Sanam; Taghizadeh Asl, Mina; Farbod, Yasaman; Teimouri, Azam; Ebrahimi Daryani, Nasser

2016-01-01

INTRODUCTION Due to limitation of colonoscopy in assessing the entire bowel and patients’ intolerance in inflammatory bowel disease (IBD), in the current study, we aimed to prospectively compare the accuracy of 99mTc(V)-dimercaptosuccinic acid (DMSA) and fecal calprotectin with ileocolonoscopy as new methods for localizing inflammations. METHODS Current prospective study conducted between 2012 and 2014 on 30 patients with IBD attending Gastroenterology Clinic of Tehran University of Medical Sciences. Fecal calprotectin and disease activity were measured for all participants and all of them underwent 99mTc (V)-DMSA scintigraphy and colonoscopy. The accuracy of 99mTc (V)-DMSA scintigraphy and calprotectin in localizing bowel lesions were calculated. RESULTS A total of 22 patients with ulcerative colitis (UC) and 8 patients with Crohn’s disease (CD) were evaluated in our study. Sensitivity, positive likelihood ratio (PLR), and positive predictive value (PPV) of scintigraphy and calprotectin over colonoscopy in localization of UC lesions were 86.36%, 0.86%, 100.00% and 90.91%, 0.91, and 100.00%, respectively. Meanwhile, it showed 66.67% sensitivity and 81.25% specificity with PLR=3.56, negative likelihood ratio (NLR)=0.41, PPV=84.21%, and negative predictive value (NPV)= 61.90% in localizing lesions in patients with CD. The calprotectin level had sensitivity, PLR, and PPV of 90.00%, 0.90, and 100.00% in detecting active disease over colonoscopy, respectively. CONCLUSION The 99mTc (V)-DMSA scintigraphy would be an accurate method for detecting active inflammation in follow-up of patients with IBD and assessing response to treatment as a non-invasive and complementary method beside colonoscopy for more accurate diagnosis of CD or UC. PMID:27698971

Removal of heavy metals from aqueous systems with thiol functionalized superparamagnetic nanoparticles.

PubMed

Yantasee, Wassana; Warner, Cynthia L; Sangvanich, Thanapon; Addleman, R Shane; Carter, Timothy G; Wiacek, Robert J; Fryxell, Glen E; Timchalk, Charles; Warner, Marvin G

2007-07-15

We have shown that superparamagnetic iron oxide (Fe3O4) nanoparticles with a surface functionalization of dimercaptosuccinic acid (DMSA) are an effective sorbent material for toxic soft metals such as Hg, Ag, Pb, Cd, and Tl, which effectively bind to the DMSA ligands and for As, which binds to the iron oxide lattices. The nanoparticles are highly dispersible and stable in solutions, have a large surface area (114 m2/g), and have a high functional group content (1.8 mmol thiols/g). They are attracted to a magnetic field and can be separated from solution within a minute with a 1.2 T magnet. The chemical affinity, capacity, kinetics, and stability of the magnetic nanoparticles were compared to those of conventional resin based sorbents (GT-73), activated carbon, and nanoporous silica (SAMMS) of similar surface chemistries in river water, groundwater, seawater, and human blood and plasma. DMSA-Fe3O4 had a capacity of 227 mg of Hg/g, a 30-fold larger value than GT-73. The nanoparticles removed 99 wt% of 1 mg/L Pb within a minute, while it took over 10 and 120 min for Chelex-100 and GT-73 to remove 96% of Pb.

Description of 3,180 Courses of Chelation with Dimercaptosuccinic Acid in Children ≤5 y with Severe Lead Poisoning in Zamfara, Northern Nigeria: A Retrospective Analysis of Programme Data

PubMed Central

Thurtle, Natalie; Greig, Jane; Cooney, Lauren; Amitai, Yona; Ariti, Cono; Brown, Mary Jean; Kosnett, Michael J.; Moussally, Krystel; Sani-Gwarzo, Nasir; Akpan, Henry; Shanks, Leslie; Dargan, Paul I.

2014-01-01

Background In 2010, Médecins Sans Frontières (MSF) discovered extensive lead poisoning impacting several thousand children in rural northern Nigeria. An estimated 400 fatalities had occurred over 3 mo. The US Centers for Disease Control and Prevention (CDC) confirmed widespread contamination from lead-rich ore being processed for gold, and environmental management was begun. MSF commenced a medical management programme that included treatment with the oral chelating agent 2,3-dimercaptosuccinic acid (DMSA, succimer). Here we describe and evaluate the changes in venous blood lead level (VBLL) associated with DMSA treatment in the largest cohort of children ≤5 y of age with severe paediatric lead intoxication reported to date to our knowledge. Methods and Findings In a retrospective analysis of programme data, we describe change in VBLL after DMSA treatment courses in a cohort of 1,156 children ≤5 y of age who underwent between one and 15 courses of chelation treatment. Courses of DMSA of 19 or 28 d duration administered to children with VBLL ≥ 45 µg/dl were included. Impact of DMSA was calculated as end-course VBLL as a percentage of pre-course VBLL (ECP). Mixed model regression with nested random effects was used to evaluate the relative associations of covariates with ECP. Of 3,180 treatment courses administered, 36% and 6% of courses commenced with VBLL ≥ 80 µg/dl and ≥ 120 µg/dl, respectively. Overall mean ECP was 74.5% (95% CI 69.7%–79.7%); among 159 inpatient courses, ECP was 47.7% (95% CI 39.7%–57.3%). ECP after 19-d courses (n = 2,262) was lower in older children, first-ever courses, courses with a longer interval since a previous course, courses with more directly observed doses, and courses with higher pre-course VBLLs. Low haemoglobin was associated with higher ECP. Twenty children aged ≤5 y who commenced chelation died during the period studied, with lead poisoning a primary factor in six deaths. Monitoring of alanine transaminase (ALT), creatinine, and full blood count revealed moderate ALT elevation in <2.5% of courses. No clinically severe adverse drug effects were observed, and no laboratory findings required discontinuation of treatment. Limitations include that this was a retrospective analysis of clinical data, and unmeasured variables related to environmental exposures could not be accounted for. Conclusions Oral DMSA was a pharmacodynamically effective chelating agent for the treatment of severe childhood lead poisoning in a resource-limited setting. Re-exposure to lead, despite efforts to remediate the environment, and non-adherence may have influenced the impact of outpatient treatment. Please see later in the article for the Editors' Summary PMID:25291378

[Somatostatin receptor scintigraphy in medullary thyroid carcinomas, GEP and carcinoid tumors].

PubMed

Eising, E G; Farahati, J; Bier, D; Knust, E J; Reiners, C

1995-02-01

For this study, 24 patients with medullary thyroid cancer (MTC) and 10 with carcinoid-/GEP-tumours underwent scintigraphy with 123I-Tyr3-octreotide or 111In-DTPA-D-Phe1-octreotide (Octreoscan) or 99mTc-V-DMSA. Calcitonin and CEA were elevated in MTC patients, the other had tumour lesions on CT. Octreoscan-scintigraphy was positive in 68% of all suspicious cases. On the other hand, 123I-Tyr3-octreotide showed only rarely positive results. 99mTc-V-DMSA-scans in MTC patients were positive in 23%. Liver metastases could be seen only with Octreoscan in the non-MTC-group. These results showed better sensitivity of 111In-labelled octreotide.

Prevalence and risk factors for renal scars in children with febrile UTI and/or VUR: A cross-sectional observational study of 565 consecutive patients

PubMed Central

Snodgrass, Warren T.; Shah, Anjana; Yang, Mary; Kwon, Jeannie; Villanueva, Carlos; Traylor, Janelle; Pritzker, Karen; Nakonezny, Paul A.; Haley, Robert W.; Bush, Nicol Corbin

2013-01-01

Purpose To determine prevalence and risk factors for renal scar in children referred for urologic assessment of febrile UTI and/or VUR. Methods Pre-determined risk factors for renal scar were prospectively recorded in consecutive patients referred for UTI/VUR. Age, gender, VUR grade, and reported number of febrile and non-febrile UTIs were analyzed with logistic regression to determine risk for focal cortical defects on non-acute DMSA. Results Of 565 consecutive children, 24 (4%) had congenital renal dysplasia and 84 (15.5%) had focal defect(s). VUR, especially grades IV–V, recurrent febrile UTI, and older age increased risk. For any age child with the same number of UTIs, VUR increased odds of renal defect 5.4-fold (OR = 5.4, 95% CI = 2.7–10.6, AUC = 0.759). Conclusions Focal DMSA defects were present in 15.5% of 565 consecutive children referred for febrile UTI and/or VUR; 4% had presumed congenital reflux nephropathy without cortical defect. All VUR grades increased risk for these defects, as did recurrent febrile UTIs and older age. However, 43% with grades IV–V VUR and 76% with recurrent UTI had normal DMSA. PMID:23465483

Prevalence and risk factors for renal scars in children with febrile UTI and/or VUR: a cross-sectional observational study of 565 consecutive patients.

PubMed

Snodgrass, Warren T; Shah, Anjana; Yang, Mary; Kwon, Jeannie; Villanueva, Carlos; Traylor, Janelle; Pritzker, Karen; Nakonezny, Paul A; Haley, Robert W; Bush, Nicol Corbin

2013-12-01

To determine prevalence and risk factors for renal scar in children referred for urologic assessment of febrile UTI and/or VUR. Pre-determined risk factors for renal scar were prospectively recorded in consecutive patients referred for UTI/VUR. Age, gender, VUR grade, and reported number of febrile and non-febrile UTIs were analyzed with logistic regression to determine risk for focal cortical defects on non-acute DMSA. Of 565 consecutive children, 24 (4%) had congenital renal dysplasia and 84 (15.5%) had focal defect(s). VUR, especially grades IV-V, recurrent febrile UTI, and older age increased risk. For any age child with the same number of UTIs, VUR increased odds of renal defect 5.4-fold (OR = 5.4, 95% CI = 2.7-10.6, AUC = 0.759). Focal DMSA defects were present in 15.5% of 565 consecutive children referred for febrile UTI and/or VUR; 4% had presumed congenital reflux nephropathy without cortical defect. All VUR grades increased risk for these defects, as did recurrent febrile UTIs and older age. However, 43% with grades IV-V VUR and 76% with recurrent UTI had normal DMSA. Published by Elsevier Ltd.

Biotransformation of magnetic nanoparticles as a function of coating in a rat model

NASA Astrophysics Data System (ADS)

Ruiz, A.; Gutiérrez, L.; Cáceres-Vélez, P. R.; Santos, D.; Chaves, S. B.; Fascineli, M. L.; Garcia, M. P.; Azevedo, R. B.; Morales, M. P.

2015-10-01

Long-term in vivo studies in murine models have shown that DMSA-coated nanoparticles accumulate in spleen, liver and lung tissues during extended periods of time (at least up to 3 months) without any significant signs of toxicity detected. During that time, nanoparticles undergo a process of biotransformation either by reducing the size or the particle aggregation or both. Using a rat model, we have evaluated the transformations of magnetic nanoparticles injected at low doses. Particles with two different coatings, dimercaptosuccinic acid (NP-DMSA) and polyethylene glycol (NP-PEG-(NH2)2) have been administered to animals, to evaluate the role of coating in the degradation of the particles. We have found that low doses of magnetic nanoparticles are quickly metabolized by the animals. In fact, using a nanoparticle dose four times lower than in previous experiments, NP-DMSA were not observed 24 h after the administration either in the liver or in the lungs. Interestingly, an increased amount of ferritin, the iron storage protein, was observed in liver tissues from rats that were treated with the low dose of NP-DMSA in comparison with the control ones, suggesting a rapid metabolization of the particles into ferritin iron. On the other side we have found that, NP-PEG-(NH2)2 are still detectable in several organs 24 h after their administration at low doses. Probably, due to the longer circulation times of the NP-PEG-(NH2)2, there is a delay in the arrival of the particles to the tissue and this is the reason why we are able to see the particles 24 h post-administration. PEG coating could also be protecting the nanoparticles from rapid degradation of the reticuloendothelial system. Knowledge on the biodistribution, circulation time and degradation processes is required to gain a better understanding of the safety evaluation of this kind of nanomaterial for biomedical applications.

Urine interleukin-6, interleukin-8 and transforming growth factor β1 in infants with urinary tract infection and asymptomatic bacteriuria

PubMed Central

Krzemień, Grażyna; Turczyn, Agnieszka; Pańczyk-Tomaszewska, Małgorzata

2016-01-01

Introduction Urinary tract infection (UTI) occurs in 1.1% of girls and 1.4% of boys during the first year of life. Asymptomatic bacteriuria (ABU) is usually detected incidentally in 0.9% of girls and 2.5% of boys at this age. The aim of the study was to assess the usefulness of measurement of pro-inflammatory urine interleukin (IL)-6 and IL-8 concentrations and anti-inflammatory transforming growth factor β1 (TGF-β1) level in infants with febrile UTI, non-febrile UTI and ABU. Material and methods A total of 35 children, mean age 6.14 ±3.47 months, were divided into three groups: group I – febrile UTI (n = 13), group II – non-febrile UTI (n = 13) and group III – ABU (n = 9). At the time of enrollment urine IL-6, IL-8, TGF-β1 and serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood cell count (WBC) were measured. Renal ultrasound was performed in all children, 99mTc-dimercaptosuccinic acid scintigraphy (DMSA) and voiding cystourethrography in children with UTI. Results Urine concentrations of IL-6 and IL-8 were significantly higher in febrile UTI compared to those with non-febrile UTI and ABU (p < 0.5, p < 0.01) and positively correlated with CRP, ESR and WBC (p < 0.01). Urine levels of TGF-β1 were significantly higher in children with febrile UTI compared to those with ABU (p < 0.05) and positively correlated with WBC (p < 0.01). Inflammatory changes in the DMSA scan were detected in 66.6% of children with UTI. No significant difference in frequency of an abnormal DMSA scan compared to a normal scan was found in groups with febrile and non-febrile UTI. No relations between urine cytokines, systemic inflammatory markers and changes in DMSA scan were observed. The cutoff value for detection of inflammatory changes in the DMSA scan for IL-8 was 120 pg/mg creatinine (Cr) and 40 pg/mg Cr for TGF-β1. Based on this value, the sensitivity for IL-8 was 58.3%, specificity 100% and for TGF-β1 66.7% and 83.7%, respectively. Conclusions We found significant differences in children with febrile UTI and ABU regarding urine IL-6, IL-8 and TGF-β1 levels. Urine cytokines and systemic inflammatory markers do not differentiate between upper and lower UTI in infants. PMID:27833443

Ameliorative effects of Bacopa monniera on lead-induced oxidative stress in different regions of rat brain.

PubMed

Velaga, Manoj Kumar; Basuri, Charan Kumar; Robinson Taylor, Kendra S; Yallapragada, Prabhakara Rao; Rajanna, Sharada; Rajanna, Bettaiya

2014-07-01

Bacopa monniera is a rejuvenating herb for brain cells enhancing learning and cognitive ability. In the present investigation, the ameliorative effects of Bacopa monniera were examined against lead-induced oxidative stress in different regions of rat brain. Male rats were divided into five groups: control (1000 ppm sodium acetate) and exposed (1000 ppm lead acetate) for 4 weeks; DMSA (Meso-2,3-Dimercaptosuccinic acid)-treated (90 mg/kg body weight/day); Bacopa monniera-treated (BM) (10 mg/kg body weight/day) and a combination of BM + DMSA for seven consecutive days after 4 weeks of lead exposure. After treatment, the whole brain was isolated by sacrificing rats and four regions were separated namely cerebellum, hippocampus, frontal cortex and brain stem. Results indicated a significant (p < 0.05) increase in reactive oxygen species (ROS), lipid peroxidation products (LPP) and total protein carbonyl content (TPCC) in association with tissue metal content in all the four regions of brain for exposed group compared with their respective controls. However, the lead-induced ROS, LPP, TPCC and tissue metal content were lowered on treatment with Bacopa monniera, almost reaching the control group values in all the above brain regions compared to DMSA and a combination therapy. Results suggest that Bacopa monniera can mitigate the lead induced-oxidative stress tissue specifically by pharmacologic interventions which encompass both chelation as well as antioxidant functions.

Ultra-small particles of iron oxide as peroxidase for immunohistochemical detection

NASA Astrophysics Data System (ADS)

Wu, Yihang; Song, Mengjie; Xin, Zhuang; Zhang, Xiaoqing; Zhang, Yu; Wang, Chunyu; Li, Suyi; Gu, Ning

2011-06-01

Dimercaptosuccinic acid (DMSA) modified ultra-small particles of iron oxide (USPIO) were synthesized through a two-step process. The first step: oleic acid (OA) capped Fe3O4 (OA-USPIO) were synthesized by a novel oxidation coprecipitation method in H2O/DMSO mixing system, where DMSO acts as an oxidant simultaneously. The second step: OA was replaced by DMSA to obtain water-soluble nanoparticles. The as-synthesized nanoparticles were characterized by TEM, FTIR, TGA, VSM, DLS, EDS and UV-vis. Hydrodynamic sizes and Peroxidase-like catalytic activity of the nanoparticles were investigated. The hydrodynamic sizes of the nanoparticles (around 24.4 nm) were well suited to developing stable nanoprobes for bio-detection. The kinetic studies were performed to quantitatively evaluate the catalytic ability of the peroxidase-like nanoparticles. The calculated kinetic parameters indicated that the DMSA-USPIO possesses high catalytic activity. Based on the high activity, immunohistochemical experiments were established: using low-cost nanoparticles as the enzyme instead of expensive HRP, Nimotuzumab was conjugated onto the surface of the nanoparticles to construct a kind of ultra-small nanoprobe which was employed to detect epidermal growth factor receptor (EGFR) over-expressed on the membrane of esophageal cancer cell. The proper sizes of the probes and the result of membranous immunohistochemical staining suggest that the probes can be served as a useful diagnostic reagent for bio-detection.

Urinary tract infection in infants: a single-center clinical analysis in southern Taiwan.

PubMed

Wu, Jen-Hsi; Chiou, Yee-Hsuan; Chang, Jenn-Tzong; Wang, Hsiao-Ping; Chen, Ying-Yao; Hsieh, Kai-Sheng

2012-10-01

This study summarized the epidemiology, etiology, and susceptibility of pathogens to antibiotics, and specific characteristics in infants aged less than 4 months diagnosed with urinary tract infection in the past decade in Taiwan. The medical charts of patients aged less than 4 months admitted for urinary tract infection to Kaohsiung Veterans General Hospital between January 2001 and December 2009 were retrospectively reviewed. A total of 132 patients, with male predominance (68.9%), were enrolled. The top three pathogens were similar to those identified in previous studies in Taiwan. The most common pathogen, Escherichia coli (85.3%), was resistant to ampicillin (75.9%), followed by sulfamethoxazole/trimethoprim (31.7%), and cefazolin (28.5%). Dimercaptosuccinic acid (DMSA) renal scan revealed 34.5% positive findings, while the vesicoureteral reflux (VUR) rate was 37.8% by direct radionuclide voiding cystography and/or voiding cysto-urethrography. Positive DMSA findings significantly correlated with VUR (p<0.001) and higher C-reactive protein level (p<0.05). E coli was the most common pathogen in the present cohort, and the top three pathogens were similar to those found in general pediatric population in Taiwan. VUR was the most common genitourinary tract anomaly in this age group. Positive DMSA was well correlated with VUR and higher C-reactive protein level. Copyright © 2012. Published by Elsevier B.V.

An audit of RCP guidelines on DMSA scanning after urinary tract infection.

PubMed

Deshpande, P V; Jones, K V

2001-04-01

To assess the outcome of imaging investigations carried out in children with urinary tract infection (UTI), to compare the investigations with national guidelines, and to assess the impact on management. Retrospective review of inpatients and outpatients, aged 0-12 years, referred to the University Hospital of Wales Healthcare Trust between February 1997 and January 1998 with UTI. All children without bacterial evidence of UTI and children previously investigated for antenatal urological anomalies, major congenital anomalies, or UTI were excluded. A total of 164 children (51 boys, 113 girls) were included. Thirteen of 56 infants (23%) and 82/108 older children (76%) were diagnosed at home over one year. The prevalence of dilatation on ultrasound was 8%, renal scarring on dimercaptosuccinic acid (DMSA) scan was 11%, and vesicoureteric reflux (VUR) was 34% when investigations were carried out following guidelines published by the Royal College of Physicians. In children aged 1-6 years, the prevalence of scarring was 1/54 (2%) in those treated at home and 6/18 (33%) in inpatients. The low yield of positive results and lack of evidence of impact on management indicate that DMSA scanning, with all the implications of isotope exposure, intravenous injection, staff time, psychological trauma, and expense, could be omitted in children over 1 year with first simple UTI not sufficiently ill to be admitted to hospital. The low rate of detection of UTI in primary care in infants may represent under diagnosis.

Whole-cell bioreporters and risk assessment of environmental pollution: A proof-of-concept study using lead.

PubMed

Zhang, Xiaokai; Qin, Boqiang; Deng, Jianming; Wells, Mona

2017-10-01

As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment. We study a specific test case concerning the bioavailability of lead (Pb) in aqueous environments containing Pb-complexing ligands. Ligands studied include ethylene diamine tetra-acetic acid (EDTA), meso-2,3 dimercaptosuccinic acid (DMSA), leucine, methionine, cysteine, glutathione, and humic acid (HA), and we also performed experiments using natural water samples from Lake Tai (Taihu), the third largest lake in China. We find that EDTA, DMSA, cysteine, glutathione, and HA amendment significantly reduced Pb bioavailability with increasing ligand concentration according to a log-sigmoid trend. Increasing dissolved organic carbon in Taihu water also had the same effect, whereas leucine and methionine had no notable effect on bioavailability at the concentrations tested. We find that bioreporter results are in accord with the reduction of aqueous Pb 2+ that we expect from the relative complexation affinities of the different ligands tested. For EDTA and HA, for which reasonably accurate ionization and complexation constants are known, speciation modeling is in agreement with bioreporter response to within the level of uncertainty recognised as reasonable by the United States Environmental Protection Agency for speciation-based risk assessment applications. These findings represent a first step toward using bioreporter technology to streamline the biological confirmation or validation of speciation modeling for use in environmental risk assessment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Leishmanicidal activity of amphotericin B encapsulated in PLGA-DMSA nanoparticles to treat cutaneous leishmaniasis in C57BL/6 mice.

PubMed

de Carvalho, Ricardo Fontoura; Ribeiro, Ieler Ferreira; Miranda-Vilela, Ana Luisa; de Souza Filho, José; Martins, Olímpia Paschoal; Cintra e Silva, Débora de Oliveira; Tedesco, Antônio Cláudio; Lacava, Zulmira Guerrero Marques; Báo, Sônia Nair; Sampaio, Raimunda Nonata Ribeiro

2013-10-01

The major goal of this work was to design a new nanoparticle drug delivery system for desoxycholate amphotericin B (D-AMB), based on controlled particle size, looking for the most successful release of the active agents in order to achieve the best site-specific action of the drug at the therapeutically optimal rate and dose regimen. For this, AMB nanoencapsulated in poly(lactic-co-glycolic acid) (PLGA) and dimercaptosuccinic acid (DMSA) nanoparticles (Nano-D-AMB) has been developed, and its efficacy was evaluated in the treatment of experimental cutaneous leishmaniasis in C57BL/6 mice, to test if our nano-drug delivery system could favor the reduction of the dose frequency required to achieve the same therapeutic level of free D-AMB, and so, an extended dosing interval. Magnetic citrate-coated maghemite nanoparticles were added to this nanosystem (Nano-D-AMB-MG) aiming to increase controlled release of AMB by magnetohyperthermia. Female mice (N=6/group) were infected intradermally in the right footpad with promastigotes of Leishmania amazonensis in the metacyclic phase, receiving the following intraperitoneal treatments: 1% PBS for 10 consecutive days; D-AMB at 2 mg/kg/day for 10 days (totalizing 20 mg/kg/animal); Nano-D-AMB and Nano-D-AMB-MG at 6 mg/kg on the 1st, 4th and 7th days and at 2 mg/kg on the 10th day, also totalizing 20 mg/kg/animal by treatment end. The Nano-D-AMB-MG group was submitted to an AC magnetic field, allowing the induction of magnetohyperthermia. The evaluations were through paw diameter measurements; parasite number and cell viability were investigated by limiting dilution assay. D-AMB-coated PLGA-DMSA nanoparticles showed the same efficacy as free D-AMB to reduce paw diameter; however, the Nano-D-AMB treatment also promoted a significantly greater reduction in parasite number and cell viability compared with free D-AMB. The nano-drug AMB delivery system appeared more effective than free D-AMB therapy to reduce the dose frequency required to achieve the same therapeutic level. It thus favors a longer interval between doses, as expected with development of a new nano drug delivery system, and may be useful in the treatment of many different pathologies, from cancer to neurodegenerative diseases. Copyright © 2013 Elsevier Inc. All rights reserved.

The effect of vitamin E or vitamin A on the prevention of renal scarring in children with acute pyelonephritis.

PubMed

Sobouti, Behnam; Hooman, Nakysa; Movahed, Mansour

2013-02-01

Numerous factors may contribute to renal tissue injury after urinary tract infection. We have evaluated the effects of vitamins A or E supplementation in combination with antibiotics for the prevention of renal scarring in acute pyelonephritis. A simple non-blind randomized clinical trial was conducted on 61 children aged 1 month to 10 years between 2004 and 2006. The inclusion criteria were positive urine culture, clinical findings, and 99mTc-dimercaptosuccinic acid (DMSA) scintigraphy-based evidence in favor of acute pyelonephritis. The children were randomized into three treatment groups: 10-day treatment with only antibiotics (control group; n = 25) and 10-day treatment with supplements of vitamin A (n = 17) or vitamin E (n = 18) in addition to antibiotics during the acute phase of infection. The final analysis was performed after excluding male patients. Each patient was evaluated twice by 99mTc-DMSA scintigraphy performed at least 6 months apart. P < 0.05 was considered to be statistically significant. The analysis included 108 kidney units. The frequency of inflammation at the beginning of therapy was not significantly different in the three groups (63.3 % in vitamin A, 61 % in vitamin E, and 76.2 % in the control group). A worsening of lesions, based on the second 99mTc-DMSA scan, was observed in 42.5, 0, and 23.3 % of the control, vitamin E, and vitamin A patients, respectively (LR = 26.3, P < 0.001). Vitamins A or E supplements were effective in reducing renal scarring secondary to acute pyelonephritis.

Evaluation of 99mtechnetium-radiopharmaceutical binding to blood elements using different trichloroacetic acid concentrations.

PubMed

Freitas, R S; Gutfilen, B; da Fonseca, L M; Bernardo-Filho, M

1996-01-01

Secure determination of the binding of 99mTc-radiopharmaceuticals to plasma (P) and blood cell (BC) constituents can help to understand the biodistribution of radiophamaceuticals. The reported precipitation studies of blood with radiopharmaceuticals have shown that the results can not be easily compared between studies. We decided to determine the "gold standard" concentration of trichloroacetic acid (TCA) to evaluate the binding to blood elements for several radiopharmaceuticals used in routine nuclear medicine. We have studied phytic (99mTc-PHY), diethylenetriaminepentaacetic (99mTc-DTPA), glucoheptonic (99mTc-GHA) and dimercaptosuccinic (99mTc-DMSA) acids. Blood was incubated with radiopharmaceuticals, centrifuged and P and BC separated. Samples of P and BC were also precipitated with TCA concentrations (20.0, 10.0, 5.0, 1.0, 0.5 and 0.1 percent) and soluble (SF) and insoluble fractions (IF) were isolated. The percent radioactivity (percent rad) in IF-P depends on TCA concentration. It varied from 36.4 to 65.0 (99mTc-PHY), from 17.9 to 32.0 (99mTc-DTPA), from 11.5 to 38.8 (99mTc-GHA) and from 52.8 to 66.2 (99mTc-DMSA). The results for the binding of 99mTc-PHY to IF-P show that there was no differences in the percent rad when TCA concentrations of 0.1 to 1.0 percent were used. For 99mTc-DTPA, 5.0 percent is the best TCA concentration. For 99mTc-GHA, low values of percent rad bound to IF-P is found with TCA concentrations of 0.1, 0.5 and 1.0. Interestingly, with 99mTc-DMSA, high values of bound radioactivity are not dependent on TCA concentrations (0.1 to 10.0). Radioactivity in IF-BC depends on TCA concentration and it varied for 99mTc-PHY (80.1 to 54.1) and for 99mTc-GHA (85.5 to 61.7). With 99mTc-DTPA and with 99mTc-DMSA the percent rad in IF-BC seems independent of TCA concentration. We suggest that the evaluation of the binding of the various 99mTc-radiopharmaceuticals to blood constituents, using only one TCA concentration, should be avoided.

The role of serum and urine interleukin-8 on acute pyelonephritis and subsequent renal scarring in children.

PubMed

Sheu, Ji-Nan; Chen, Shan-Ming; Meng, Meng-Hsiao; Lue, Ko-Huang

2009-10-01

Interleukin (IL)-8 acts as a potent neutrophils chemoattractant responsible for the migration of neutrophils into the infected renal tissue to protect against invading pathogens. The aim of this study was to assess the role of IL-8 on acute-phase pyelonephritis and later renal scarring in children. A total of 124 children with a first-time febrile urinary tract infection (UTI) were studied. The diagnosis of acute pyelonephritis was confirmed by Tc-dimercaptosuccinic acid (DMSA) renal scan. Serum and urine samples were obtained from 124 children with UTI and 20 healthy children for IL-8 measurement. The 124 children were divided into acute pyelonephritis (n = 70) and lower UTI (n = 54) groups according to the results of DMSA scans. The initial serum and urine IL-8 values of children with acute pyelonephritis were significantly higher when compared with lower UTI and healthy controls (all P < 0.001). Renal scarring was seen in 26 (38.8%) of these 67 children with acute pyelonephritis at follow-up DMSA scans. Both the initial serum and urine IL-8 concentrations were significantly higher in children with renal scarring than in those without (both P < 0.001). The mean age of children with renal scarring was also significantly lower than those without scarring (P = 0.004). Multivariate analysis showed that the highest initial IL-8 values, age <20 months and reflux grades > or =III all were independent predictors of renal scarring. Those children younger than 2 years of age with the highest IL-8 concentrations during the acute phase of pyelonephritis as well as children with reflux grades of III or greater are at a high-risk for developing renal scarring in the future.

The results of different diagnostic imaging studies used in children with urinary tract infection

PubMed Central

Alghamdi, Ahmed Hassan; Ghamdi, Jameel Al; Al-Dammas, Ali

2015-01-01

Urinary tract infections (UTI) can cause significant renal scarring, which can be complicated by hypertension and renal impairment. This study describes the outcome of different imaging modalities in children with UTI and its relation to age, sex and type of UTI. Our objective was to describe the frequencies of different imaging studies, which were used to investigate children with UTI at King Fahad Hospital (KFH) between the years 2003 and 2008. This is a descriptive study of all children presenting with UTI at KFH from 2003 to 2008. The study population, 100 children, were divided into 3 age groups; first group (> 1 month to 2 years); second group (> 2 to 5 years), third group (> 5 to 12 years). All enrolled children were confirmed to have had UTI via urinary cultures. Ninety seven (97%) patients underwent renal ultrasonography (US), 77 (77%) had a 99mTc-dimercaptosuccinic acid (DMSA) scan within 2 months of presentation, and 60 (60%) patients underwent micturating cystourethrogram (MCUG), mainly those with an abnormal DMSA scan. A total of 100 patients screened, 10 (10%) were males and 90 (90%) were females, first age group constituted 10%, second age group was 25%, third age groups was 65%. E-coli was isolated in 84% of patients, 60% had recurrent UTI, 45% had pyelonephritis, 48.4% had abnormal renal US, 61% had an abnormal DMSA scan, and 26.6% had abnormal MCUG. UTI can cause significant morbidity in children if not managed properly. Imaging studies are useful in identifying children who require advanced medical intervention; however, such studies should be performed only when indicated. PMID:27493418

Utility of screening ultrasound after first febrile UTI among patients with clinically significant vesicoureteral reflux.

PubMed

Massanyi, Eric Z; Preece, Janae; Gupta, Angela; Lin, Susan M; Wang, Ming-Hsien

2013-10-01

To assess the sensitivity and negative predictive value (NPV) of screening renal and bladder ultrasound (RBUS) after initial febrile urinary tract infection (UTI) among patients with clinically significant vesicoureteral reflux (VUR). A retrospective review was performed of all children <2 years of age who presented with a febrile UTI between 2004 and 2011. The sensitivity and NPV of initial RBUS was calculated among patients who were found to have high-grade (IV-V) VUR. Additionally, initial RBUS among patients with evidence of photopenia on dimercaptosuccinic acid (DMSA) scan or who underwent surgical intervention were reviewed. One hundred forty-four patients with febrile UTI were identified; available RBUS, voiding cystourethrogram (VCUG), and DMSA results for each kidney were reviewed. One hundred fifty-eight kidneys had evidence of VUR on VCUG, and initial RBUS demonstrated abnormality in 25 (sensitivity 0.17). Forty-five kidneys had high-grade VUR and RBUS revealed abnormality in 16 (sensitivity 0.36). One hundred seventy-eight kidneys had no evidence of abnormality on initial RBUS, and 136 (76%) were found to have VUR (NPV 0.24), of which 31 had high-grade VUR (NPV 0.83). Seven kidneys had scarring on DMSA and initial RBUS was normal in 4 (57%). Twelve of 19 patients (63%) who eventually underwent surgical intervention had a normal initial RBUS. RBUS has poor sensitivity and NPV for detecting high-grade VUR in patients <2 years who present with a febrile UTI. A significant number of patients who were diagnosed with high-grade VUR, renal scarring, or underwent surgical correction of VUR had a negative screening RBUS. Copyright © 2013 Elsevier Inc. All rights reserved.

The presence of lead decreases the availability of meso-2, 3-dimercaptosuccinic acid for analysis in the monobromobimane assay.

PubMed

Lever, S Z; Parsons, T L

1999-11-01

meso-2,3-Dimercaptosuccinic acid is a suitable chelating agent for routine pharmacotherapy of lead poisoning in children. Administration of meso-2,3-dimercaptosuccinic acid presumably permits complexation of lead in vivo, allowing excretion through urine or feces. Quantification of the lead is achieved independently from the analysis of meso-2,3-dimercaptosuccinic acid and metabolites from the monobromobimane assay. To date, no direct chemical characterization of the Pb species excreted in urine has been successful. Pharmacokinetic correlation of lead excretion with excretion of meso-2,3-dimercaptosuccinic acid and metabolites has been utilized as an indirect method to draw conclusions regarding the identity of the active chelating agent. In this study, we hypothesized that the Pb-coordinated thiols are not reactive with respect to monobromobimane, and thus, the active chelator contained in the lead complex escapes detection. We performed variations of the assay and found that (1) the fluorescence detector response for the meso-2,3-dimercaptosuccinic acid-monobromobimane adduct was clearly attenuated as a function of added Pb, (2) when meso-2, 3-dimercaptosuccinic acid and monobromobimane were mixed prior to the addition of lead, the lead had no effect on detector response, (3) the addition of dithiothreitol does not affect the ability of Pb to react with meso-2,3-dimercaptosuccinic acid and verifies that oxidation of meso-DMSA had not occurred, and (4) the addition of ethylenediaminetetraacetic acid to the assay reverses the result found in point 1, presumably through trans chelation of the Pb-DMSA complex. Indirect quantification of the Pb-DMSA complexes found in urine might be accomplished through modification of the standard monobromobimane assay for analysis of meso-2,3-dimercaptosuccinic acid.

Vitamin E as adjuvant treatment for urinary tract infection in girls with acute pyelonephritis.

PubMed

Yousefichaijan, Parsa; Kahbazi, Manigeh; Rasti, Sara; Rafeie, Mohammad; Sharafkhah, Mojtaba

2015-03-01

Vitamin E is a fat-soluble vitamin that functions as an antioxidant. The aim of this study was to investigate the effects of vitamins E supplementation in combination with antibiotics for the treatment of girls with acute pyelonephritis. This double-blinded randomized controlled trial was conducted on 152 girls aged 5 to 12 years with a first acute pyelonephritis episode based on technetium Tc 99m dimercaptosuccinic acid (99mTc-DMSA). They were randomized to receive a 14-day treatment with only antibiotics (control group; n = 76) and 14-day treatment with supplements of vitamin E (intervention group; n = 76) in addition to the antibiotics. Patients' clinical symptoms were monitored for 14 days and urine culture was performed 3 to 4 days and 7 to 10 days after the start of the treatment and its completion, respectively. All of the girls once underwent DMSA scan 4 to 6 months after the treatment. During the follow-up days, the mean frequency of fever (P = .01), urinary frequency (P = .001), urgency (P = .003), dribbling (P = .001), and urinary incontinence (P = .006) were significantly lower in the intervention group compared to the control group. There was no significant difference in the results of urine culture 3 to 4 days after the start of treatment (P = .16) and 7 to 10 days after its termination (P = .37). There was also no significant difference between the results of DMSA scan 4 to 6 months after the start of treatment (P = .31). Vitamin E supplementation has a significant effect in ameliorating sign and symptoms of UTI. However, further studies are recommended to confirm these findings.

[Renal scarring in children under 36 months hospitalised for acute pyelonephritis].

PubMed

Rodríguez Azor, Begoña; Ramos Fernández, José Miguel; Sánchiz Cárdenas, Sonia; Cordón Martínez, Ana; Carazo Gallego, Begoña; Moreno-Pérez, David; Urda Cardona, Antonio

2017-02-01

Acute pyelonephritis (APN) is one of the most common causes of serious bacterial infection in infants. Renal scarring is the most prevalent long-term complication. To review the incidence of renal scarring within 6 months after an episode of APN in children under 36 months and its relationship with imaging studies, clinical settings, and bacteriology. A retrospective study of previously healthy patients aged one to 36 months, admitted for a first episode of APN, with a minimum follow-up of 6 months. Demographic and clinical variables were collected along with bacteriology, renal and bladder ultrasound scan, voiding cystourethrography, DMSA-scintigraphy, and re-infection events. A total of 125 patients were included in the study, of which 60% were male, the large majority (92%) febrile, and due to E. coli (74.6%). There was a history of prenatal ultrasound scan changes in 15.4%. Ultrasound scan found dilation of the urinary tract in 22.1%. Voiding cystourethrography was performed on 70 patients: 54.3% no abnormalities, 12.8% vesicoureteral reflux (VUR) grade i-iii, and 32.9% iv-v grade VUR. Six patients had iv-v grade VUR with a normal ultrasound scan. Adherence to DMSA-scintigraphy at 6 months was only 61% of that indicated. Renal scarring was found in 44.3% of those in which it was performed (60 cases). Almost half (44%) DMSA-scintigraphy in children aged one to 36 months hospitalised for APN show renal scarring at 6 months, which was found to be associated with the re-infection events and the iv-v grade VUR. There was no relationship between scarring and the bacteriology or the elevations of inflammatory biochemical markers. Copyright © 2015 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

Renal cortical involvement in children with first UTI: does it differ in the presence of primary VUR?

PubMed

Aktaş, Gül Ege; Inanir, Sabahat; Turoğlu, Halil Turgut

2008-12-01

The aim of this study was to investigate the influence of vesicoureteral reflux (VUR) on dimercaptosuccinic acid (DMSA) scintigraphic patterns in children with first symptomatic urinary tract infection (UTI). A total of 45 children with the diagnosis of first symptomatic UTI (28 girls, 17 boys, mean age 18 months, range 1 month-11 years) were reviewed. All DMSA scans were obtained within 2 months of bacteriologically proven UTI (median 21 days, mean 26 +/- 21, 14). After the exclusion of the patients with bilateral cortical lesions, 82 renal units were analyzed. The scintigraphic patterns included regional and global description of renal cortical abnormality (normal or decreased differential renal function, regional renal function (RRF), and the number and severity of cortical lesions). Vesicoureteral reflux was detected in 26 (32%) renal units (15 with grade 1-2, 11 with grade 3-4). Renal cortical abnormality was observed in 10 renal units without VUR (10/56, 17%) and 13 renal units with VUR (13/26: 50%). Of the 15 renal units, 5 with grade 1-2 VUR (5/15) and 8 of the 11 renal units with grade 3-4 VUR (8/11) had renal cortical involvement. The most common scintigraphic pattern in the patients without VUR was the preserved RRF (>or=45%) and two or fewer photon-deficient areas. On the other hand, a decreased RRF (<45) associated with cortical lesions was the most frequent finding in patients with refluxing kidneys (8/26, 30%), especially in those with grade 3-4 disease. This investigation showed that the presence of VUR affects DMSA patterns in children with first symptomatic UTI.

Positioning irrigation of contrast cystography for diagnosis of occult vesicoureteric reflux: association with technetium-99m dimercaptosuccinic acid scans.

PubMed

Berger, Christoph; Becker, Tanja; Koen, Mark; Zeino, Mazen; Fitz, Friedrich; Beheshti, Mohsen; Wolf-Kohlmeier, Iris; Haim, Silke; Riccabona, Marcus

2013-12-01

Positioning irrigation of contrast (PIC) cystography identifies occult or PIC vesicoureteral reflux (PIC-VUR) in children with recurrent febrile urinary tract infections (UTI) but no vesicoureteric reflux (VUR) on standard voiding cystourethrogram (VCUG). We sought to identify the relationship between PIC-VUR and renal scarring in technetium-99m dimercaptosuccinic acid (DMSA) scans. We retrospectively analysed PIC cystograms and DMSA scans for 154 kidneys in 81 children (65 girls; 16 boys; median age, 4.7 years; range, 0.9-15.2). Renal scarring was graded on a scale of 0-3. DMSA scans were pathologic in 66 patients (81%). Children had experienced mean 3.8 febrile UTI (range 1-25). Forty-seven (58%) children had a history of reflux, including 15 (19%) with previous anti-reflux operations. Indications for PIC cystography were recurrence of febrile UTI after either bilateral negative VCUG (66 children) or unilateral VUR (15 children) with contralateral/bilateral scarring or reflux that had changed sides in subsequent VCUGs. PIC-VUR was bilateral in 63, unilateral in 12, and absent in 6 children. Statistically significant associations between PIC-VUR grade and severity of renal scarring were identified in inter-individual (n = 77, p = 0.017) and intra-individual (refluxing vs. nonrefluxing kidney; n = 12, p = 0.008) analyses. After excluding patients with history of VUR, statistical significance was maintained in inter-individual analysis (n = 49; p = 0.018). The data suggest an association between PIC-VUR and severity of renal scarring, and legitimise the use of PIC cystography in children with renal scarring due to recurrent febrile UTI but negative findings on VCUG. Copyright © 2012 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

The Effect of Superparamagnetic Iron Oxide Nanoparticle Surface Charge on Antigen Cross-Presentation.

PubMed

Mou, Yongbin; Xing, Yun; Ren, Hongyan; Cui, Zhihua; Zhang, Yu; Yu, Guangjie; Urba, Walter J; Hu, Qingang; Hu, Hongming

2017-12-01

Magnetic nanoparticles (NPs) of superparamagnetic iron oxide (SPIO) have been explored for different kinds of applications in biomedicine, mechanics, and information. Here, we explored the synthetic SPIO NPs as an adjuvant on antigen cross-presentation ability by enhancing the intracellular delivery of antigens into antigen presenting cells (APCs). Particles with different chemical modifications and surface charges were used to study the mechanism of action of antigen delivery. Specifically, two types of magnetic NPs, γFe 2 O 3 /APTS (3-aminopropyltrimethoxysilane) NPs and γFe 2 O 3 /DMSA (meso-2, 3-Dimercaptosuccinic acid) NPs, with the same crystal structure, magnetic properties, and size distribution were prepared. Then, the promotion of T-cell activation via dendritic cells (DCs) was compared among different charged antigen coated NPs. Moreover, the activation of the autophagy, cytosolic delivery of the antigens, and antigen degradation mediated by the proteasome and lysosome were measured. Our results indicated that positive charged γFe 2 O 3 /APTS NPs, but not negative charged γFe 2 O 3 /DMSA NPs, enhanced the cross-presentation ability of DCs. Increased cross-presentation ability induced by γFe 2 O 3 /APTS NPs was associated with increased cytosolic antigen delivery. On the contrary, γFe 2 O 3 /DMSA NPs was associated with rapid autophagy. Overall, our results suggest that antigen delivered in cytoplasm induced by positive charged particles is beneficial for antigen cross-presentation and T-cell activation. NPs modified with different chemistries exhibit diverse biological properties and differ greatly in their adjuvant potentials. Thus, it should be carefully considered many different effects of NPs to design effective and safe adjuvants.

Renal Abnormalities Among Egyptian Children With Hemophilia A Using Renal Scintigraphy: Relation to Risk Factors and Disease Severity.

PubMed

Hamed, Ahmed Alsaeed; Shalaby, Mennatallah Hatem; El-Kinawy, Nihal Saad; Elamawy, Alaa Adel; Abd El-Ghany, Shereen Mohamed

2017-07-01

Many risk factors may contribute to renal disease in patients with hemophilia A. We aimed to evaluate functional and structural renal abnormalities among a group of Egyptian children with severe and moderate hemophilia A using technetium-99m diethylene triamine pentaacetic acid ( 99m Tc-DTPA) and technetium-99 m dimercaptusuccinic acid ( 99m Tc-DMSA) scan. We also aimed to determine the relation between these abnormalities and different risk factors and disease severity. Forty male patients, 16 with severe and 24 with moderate hemophilia A, were enrolled in this study. Their mean age was 10.2 ± 4.3 years (range, 5-17 years). Full history taking, clinical examination, laboratory, and radionuclide investigations including serum creatinine, blood urea nitrogen (BUN), urine analysis, creatinine clearance, 24-hour urinary protein, 99m Tc-DTPA scan, and 99m Tc-DMSA scan were performed to all enrolled patients. Serum creatinine and BUN were normal in all patients, and corrected creatinine clearance was diminished in 2 patients. However, 99m Tc-DTPA results yielded 19 (47.5%) patients with diminished glomerular filtration rate (GFR). Moreover, it showed that 14 (35%) had obstructive uropathy, 15 (37.5%) had obstructive nephropathy, while 11 (27.5%) patients showed normal scan. One patient had atrophy of 1 kidney on 99m Tc-DMSA scan. Among our cohort, 5 (12.5%) patients were hypertensive. Microscopic hematuria was detected in 14 (35%) patients while 72.5% had proteinuria. We found an association between hematuria and hypertension with diminished GFR. Despite normal kidney functions (serum creatinine and BUN), we found a high rate of diminished GFR and obstructive uropathy and nephropathy as detected by 99m Tc-DTPA scan among children with hemophilia A.

The Effect of Superparamagnetic Iron Oxide Nanoparticle Surface Charge on Antigen Cross-Presentation

NASA Astrophysics Data System (ADS)

Mou, Yongbin; Xing, Yun; Ren, Hongyan; Cui, Zhihua; Zhang, Yu; Yu, Guangjie; Urba, Walter J.; Hu, Qingang; Hu, Hongming

2017-01-01

Magnetic nanoparticles (NPs) of superparamagnetic iron oxide (SPIO) have been explored for different kinds of applications in biomedicine, mechanics, and information. Here, we explored the synthetic SPIO NPs as an adjuvant on antigen cross-presentation ability by enhancing the intracellular delivery of antigens into antigen presenting cells (APCs). Particles with different chemical modifications and surface charges were used to study the mechanism of action of antigen delivery. Specifically, two types of magnetic NPs, γFe2O3/APTS (3-aminopropyltrimethoxysilane) NPs and γFe2O3/DMSA (meso-2, 3-Dimercaptosuccinic acid) NPs, with the same crystal structure, magnetic properties, and size distribution were prepared. Then, the promotion of T-cell activation via dendritic cells (DCs) was compared among different charged antigen coated NPs. Moreover, the activation of the autophagy, cytosolic delivery of the antigens, and antigen degradation mediated by the proteasome and lysosome were measured. Our results indicated that positive charged γFe2O3/APTS NPs, but not negative charged γFe2O3/DMSA NPs, enhanced the cross-presentation ability of DCs. Increased cross-presentation ability induced by γFe2O3/APTS NPs was associated with increased cytosolic antigen delivery. On the contrary, γFe2O3/DMSA NPs was associated with rapid autophagy. Overall, our results suggest that antigen delivered in cytoplasm induced by positive charged particles is beneficial for antigen cross-presentation and T-cell activation. NPs modified with different chemistries exhibit diverse biological properties and differ greatly in their adjuvant potentials. Thus, it should be carefully considered many different effects of NPs to design effective and safe adjuvants.

Primary vesicoureteral reflux: A 26-year experience in a single centre.

PubMed

Vachvanichsanong, Prayong; Dissaneewate, Pornsak; McNeil, Edward

2016-04-01

To determine the nature of primary vesicoureteral reflux (VUR) and the association of VUR with hydronephrosis and renal damage. The medical records of children ≤ 15 years diagnosed with VUR, attending the Department of Pediatrics, Prince of Songkla University, Thailand between 1987 and 2013 were reviewed. Renal ultrasound and technetium-99m dimercaptosuccinic acid renal scan (DMSA) results were examined to determine the severity of hydronephrosis and renal damage, respectively. There were 177 boys and 211 girls. 350 (90.2%) were diagnosed following urinary tract infection (UTI). The median (IQR) age at diagnosis of first VUR was 7.6 (4.3-12.2) months in boys and 18.6 (9.0-46.6) months in girls (P < 0.001). Renal ultrasound was performed in 340 patients. Hydronephrosis was found in 105 patients and 135 kidneys and 22.5% VUR kidneys and 11.0% non-VUR kidneys (P = 0.01). The severity of hydronephrosis was associated with VUR grade (44.2% of grades IV and V VUR had hydronephrosis vs 11.9% of grades I-III VUR, P < 0.001). DMSA was performed in 332 patients. Abnormalities were found in 30.1% VUR kidneys and 4.1% non-VUR kidneys (P < 0.001). Abnormal DMSA results were strongly associated with VUR grade (17.8% for VUR grades I-III vs 60.5% for VUR grades IV and V, P < 0.001). Primary VUR in this group was most commonly diagnosed following investigation of UTI and detected during infancy, earlier in boys. Hydronephrosis and renal damage were associated with severity of VUR. © 2015 Asian Pacific Society of Nephrology.

Magnetic resonance voiding cystography in the diagnosis of vesicoureteral reflux: comparative study with voiding cystourethrography.

PubMed

Lee, Sang Kwon; Chang, Yongmin; Park, Noh Hyuck; Kim, Young Hwan; Woo, Seongku

2005-04-01

To evaluate the feasibility of magnetic resonance voiding cystography (MRVC) compared with voiding cystourethrography (VCUG) for detecting and grading vesicoureteral reflux (VUR). MRVC was performed upon 20 children referred for investigation of reflux. Either coronal T1-weighted spin-echo (SE) or gradient-echo (GE) (fast multiplanar spoiled gradient-echo (FMPSPGR) or turbo fast low-angle-shot (FLASH)) images were obtained before and after transurethral administration of gadolinium solution, and immediately after voiding. The findings of MRVC were compared with those of VCUG and technetium-99m ((99m)Tc) dimercaptosuccinic acid (DMSA) single-photon emission computed tomography (SPECT) performed within 6 months of MRVC. VUR was detected in 23 ureterorenal units (16 VURs by both methods, 5 VURs by VCUG, and 2 VURs by MRVC). With VCUG as the standard of reference, the sensitivity of MRVC was 76.2%; the specificity, 90.0%; the positive predictive value, 88.9%; and the negative predictive value, 78.3%. There was concordance between two methods regarding the grade of reflux in all 16 ureterorenal units with VUR detected by both methods. Of 40 kidneys, MRVC detected findings of renal damage or reflux nephropathy in 13 kidneys, and (99m)Tc DMSA renal SPECT detected findings of reflux nephropathy in 17 kidneys. Although MRVC is shown to have less sensitivity for VUR than VCUG, MRVC may represent a method of choice offering a safer nonradiation test that can additionally evaluate the kidneys for changes related to reflux nephropathy. Copyright 2005 Wiley-Liss, Inc.

Autism, an extreme challenge to integrative medicine. Part 2: medical management.

PubMed

Kidd, Parris M

2002-12-01

Autism and allied autistic spectrum disorders (ASD) present myriad behavioral, clinical, and biochemical abnormalities. Parental participation, advanced testing protocols, and eclectic treatment strategies have driven progress toward cure. Behavioral modification and structured education are beneficial but insufficient. Dietary restrictions, including removal of milk and other casein dairy products, wheat and other gluten sources, sugar, chocolate, preservatives, and food coloring are beneficial and prerequisite to benefit from other interventions. Individualized IgG or IgE testing can identify other troublesome foods but not non-immune mediated food sensitivities. Gastrointestinal improvement rests on controlling Candida and other parasites, and using probiotic bacteria and nutrients to correct dysbiosis and decrease gut permeability. Detoxification of mercury and other heavy metals by DMSA/DMPS chelation can have marked benefit. Documented sulfoxidation-sulfation inadequacies call for sulfur-sulfhydryl repletion and other liver p450 support. Many nutrient supplements are beneficial and well tolerated, including dimethylglycine (DMG) and a combination of pyridoxine (vitamin B6) and magnesium, both of which benefit roughly half of ASD cases. Vitamins A, B3, C, and folic acid; the minerals calcium and zinc; cod liver oil; and digestive enzymes, all offer benefit. Secretin, a triggering factor for digestion, is presently under investigation. Immune therapies (pentoxifyllin, intravenous immunoglobulin, transfer factor, and colostrum) benefit selected cases. Long-chain omega-3 fatty acids offer great promise. Current pharmaceuticals fail to benefit the primary symptoms and can have marked adverse effects. Individualized, in-depth clinical and laboratory assessments and integrative parent-physician-scientist cooperation are the keys to successful ASD management.

Profile of urinary tract infections in paediatric patients

PubMed Central

Gupta, Palak; Mandal, Jharna; Krishnamurthy, Sriram; Barathi, Deepak; Pandit, Nandini

2015-01-01

Background & objectives: This cross-sectional study was conducted at a tertiary care centre in Puducherry, south India, with the aim of finding the profile of the paediatric urinary tract infection (UTI), bacterial pathogens involved, and also to observe vesicoureteric reflux (VUR) and renal scarring in these patients. Methods: A total of 524 paediatric patients ≤13 yr, suspected to have UTI, were included in the study. Urine samples were collected, processed for uropathogen isolation and antibiotic susceptibility test was performed as per the Clinical and Laboratory Standards Institute (CLSI) guidelines. Thirty two culture proven children with UTI underwent micturating cysto-urethrography (MCU) and dimercaptosuccinic acid (DMSA) scanning was done for 69 children. Results: of the 524 children, 186 (35.4%) had culture proven UTI with 105 (56.4%) being infants, 50 (27.4%) between 1-5 yr, 30 (16.12%) between 5-13 yr and 129 (69.35%) males. Posterior urethral valve (PUV) was noted in three, hydronephrosis in one, VUR in 18 and renal scarring in 33. VUR as well as renal scarring were more in males >1 yr of age. A significant association (P=0.0054) was noted with a combined sensitivity and specificity of these investigations being 83 and 90 per cent, respectively of the MCU and DMSA scans for detecting VUR. Escherichia coli was the most common pathogen isolated, sensitive to nitrofurantoin, followed by cefoperazone-sulbactam, aminoglycosides and meropenem. Interpretation & conclusions: Our results indicate that UTI varies with age and gender and extensive evaluation is required in boys under one year of age with UTI. This study also highlights the better efficacy of aminoglycosides, cefoperazone-sulbactam and nitrofurantoin in vitro compared with meropenem in Gram–negative uropathogens. PMID:26112850

Porphyrinuria in childhood autistic disorder: Implications for environmental toxicity

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

Nataf, Robert; Skorupka, Corinne; Amet, Lorene

To address a possible environmental contribution to autism, we carried out a retrospective study on urinary porphyrin levels, a biomarker of environmental toxicity, in 269 children with neurodevelopmental and related disorders referred to a Paris clinic (2002-2004), including 106 with autistic disorder. Urinary porphyrin levels determined by high-performance liquid chromatography were compared between diagnostic groups including internal and external control groups. Coproporphyrin levels were elevated in children with autistic disorder relative to control groups. Elevation was maintained on normalization for age or to a control heme pathway metabolite (uroporphyrin) in the same samples. The elevation was significant (P < 0.001).more » Porphyrin levels were unchanged in Asperger's disorder, distinguishing it from autistic disorder. The atypical molecule precoproporphyrin, a specific indicator of heavy metal toxicity, was also elevated in autistic disorder (P < 0.001) but not significantly in Asperger's. A subgroup with autistic disorder was treated with oral dimercaptosuccinic acid (DMSA) with a view to heavy metal removal. Following DMSA there was a significant (P = 0.002) drop in urinary porphyrin excretion. These data implicate environmental toxicity in childhood autistic disorder.« less

Porphyrinuria in childhood autistic disorder: implications for environmental toxicity.

PubMed

Nataf, Robert; Skorupka, Corinne; Amet, Lorene; Lam, Alain; Springbett, Anthea; Lathe, Richard

2006-07-15

To address a possible environmental contribution to autism, we carried out a retrospective study on urinary porphyrin levels, a biomarker of environmental toxicity, in 269 children with neurodevelopmental and related disorders referred to a Paris clinic (2002-2004), including 106 with autistic disorder. Urinary porphyrin levels determined by high-performance liquid chromatography were compared between diagnostic groups including internal and external control groups. Coproporphyrin levels were elevated in children with autistic disorder relative to control groups. Elevation was maintained on normalization for age or to a control heme pathway metabolite (uroporphyrin) in the same samples. The elevation was significant (P < 0.001). Porphyrin levels were unchanged in Asperger's disorder, distinguishing it from autistic disorder. The atypical molecule precoproporphyrin, a specific indicator of heavy metal toxicity, was also elevated in autistic disorder (P < 0.001) but not significantly in Asperger's. A subgroup with autistic disorder was treated with oral dimercaptosuccinic acid (DMSA) with a view to heavy metal removal. Following DMSA there was a significant (P = 0.002) drop in urinary porphyrin excretion. These data implicate environmental toxicity in childhood autistic disorder.

Short communication: timeline of radiation-induced kidney function loss after stereotactic ablative body radiotherapy of renal cell carcinoma as evaluated by serial (99m)Tc-DMSA SPECT/CT.

PubMed

Jackson, Price; Foroudi, Farshad; Pham, Daniel; Hofman, Michael S; Hardcastle, Nicholas; Callahan, Jason; Kron, Tomas; Siva, Shankar

2014-11-26

Stereotactic ablative body radiotherapy (SABR) has been proposed as a definitive treatment for patients with inoperable primary renal cell carcinoma. However, there is little documentation detailing the radiobiological effects of hypofractionated radiation on healthy renal tissue. In this study we describe a methodology for assessment of regional change in renal function in response to single fraction SABR of 26 Gy. In a patient with a solitary kidney, detailed follow-up of kidney function post-treatment was determined through 3-dimensional SPECT/CT imaging and (51)Cr-EDTA measurements. Based on measurements of glomerular filtration rate, renal function declined rapidly by 34% at 3 months, plateaued at 43% loss at 12 months, with minimal further decrease to 49% of baseline by 18 months. The pattern of renal functional change in (99m)Tc-DMSA uptake on SPECT/CT imaging correlates with dose delivered. This study demonstrates a dose effect relationship of SABR with loss of kidney function.

Green Tea Increases the Concentration of Total Mercury in the Blood of Rats following an Oral Fish Tissue Bolus

PubMed Central

Freiser, Helene; Manganais, Christopher; Santerre, Charles R.

2015-01-01

Fish has many health benefits but is also the most common source of methylmercury. The bioavailability of methylmercury in fish may be affected by other meal components. In this study, the effect of green tea on the bioavailability of methylmercury from an oral bolus of fish muscle tissue was studied in rats and compared to a water treated control group and a group treated with meso-2,3-dimercaptosuccinic acid (DMSA), a compound used medically to chelate mercury. Rats were given a single oral dose of fish tissue via gavage and one of the treatments. Rats were given access to food for 3 h at 12 h intervals. They were dosed with each of the treatments with each meal. Blood samples were collected for 95 hours. Green tea significantly increased the concentration of total mercury in blood relative to the control, whereas DMSA significantly decreased it. In addition, feeding caused a slight increase in blood mercury for several meals following the initial dose. PMID:26301246

Paediatric Urinary Tract Infection: A Hospital Based Experience

PubMed Central

Wani, Khursheed Ahmed; Bhat, Javaid Ahmed; Parry, Nazir Ahmed; Shaheen, Lubna; Bhat, Sartaj Ali

2016-01-01

Introduction Paediatric Urinary Tract Infection (UTI) is one of the commonly encountered entities by paediatricians. Studies have shown easy vulnerability of paediatric urinary tract in any acute febrile illness and a miss in diagnosis could have long term consequences like renal scaring with its adverse effects. Bearing these evidence based preludes in view we designed our study to know the prevalence of UTI in Kashmir province. Aim Aim of the present study was to know the prevalence of UTI in febrile children and to know the sensitivity of different imaging modalities like Renal and Urinary Bladder Ultrasonography (RUS), Voiding Cystourethrography (VCUG) and Dimercaptosuccinic Acid (DMSA) scan in diagnosing UTI. Materials and Methods A total of 304 patients, between 2 months to 10 years, with axillary temperature of ≥ 100.4oF (38oC), who did not have a definite source for their fever and who were not on antibiotics were included in the study. Detailed history and through clinical examination was done to rule out any potential or definite focus of infection as per the predesigned proforma. Routine urine examination with culture and sensitivity, followed by RUS and VCUG was done in all patients where routine urine examination was suggestive of UTI. DMSA was done in only culture proven cases after 6 months to document the renal scarring. Results Out of 304 children, 140 were males and 164 were females, UTI was present in 40 patients who had fever without any apparent cause giving a prevalence of 13.2%. Escherichia coli (E. coli) were the commonest isolated organism, followed by Klebsiella and Citrobacter species. Renal and Urinary Bladder Ultrasonography (RUS) detected Vesicoureteral Reflux (VUR) in 25% (10/40) while VCUG showed VUR in 55% (22/40) giving a RUS sensitivity of 45% for detecting VUR. DMSA done only after 6 months in UTI diagnosed patients showed a renal scarring in 25% (10/40) patients. Conclusion Missing a febrile paediatric UTI, can prove a future catastrophe if not timely diagnosed and treated. PMID:27891414

[Urinary tract infections--pediatric urologist point of view].

PubMed

Baka-Ostrowska, Małgorzata

2008-01-01

Urinary tract infections (UTI) could present with different clinical forms dependent on intensity and localization of infection and child's age. The symptoms could be non specific in children. Condition that provoke to urinary stasis, especially voiding dysfunction is the favourable factor for UTI appearance. Gram-negative enteric bacteria is the most common pathogen. Urine culture is the basic investigation that allow to identify pathogen and its drug sensitiveness but simultaneous urinalysis is necessary to recognize the inflammation of urinary organs. In addition, the number of leukocytes gives an idea about inflammation intensity. Ultrasonographic (USG) scan is necessary to examine urostasis. DMSA study performed during febrile UTI allow to identify children with acute pyelonephritis and when repeated 6 months later - those with renal scars. A normal USG and DMSA scan during infection makes voiding cystourethrography (VCU) unnecessary in the primary examination. The presence of vesicoureteric reflux (VUR) not always predispose children to renal lesions. Early and appropriate treatment of UTI, especially during the first 24 hours, diminishes the likelihood of renal involvement during the acute phase of infection but does not prevent scar formation. The proper hygiene of the urethral meatus, voiding and drinking habits and preventing of constipation are crucial in UTI prophylaxis.

[Calculation of the partial function of the kidney with DMSA in pediatrics: is the evaluation of the geometric mean necessary?].

PubMed

Porn, U; Rossmüller, B; Alalp, S; Fischer, S; Dresel, S; Hahn, K

2001-08-01

For assessment of differential renal function (PF) by means of static renal scintigraphy with Tc-99m-dimercaptosuccinic acid (DMSA) the calculation of the geometric mean of counts from the anterior and posterior view is recommended. Of this retrospective study was to find out, if the anterior view is necessary to receive an accurate differential renal function by calculating the geometric mean compared to calculating PF using the counts of the posterior view only. 164 DMSA-scans of 151 children (86 f, 65 m) aged 16 d to 16 a (4.7 +/- 3.9 a) were reviewed. The scans were performed using a dual head gamma camera (Picker Prism 2000 XP, low energy ultra high resolution collimator, matrix 256 x 256, 300 kcts/view, Zoom: 1.6-2.0). Background corrected values from both kidneys anterior and posterior were obtained. Using region of interest technique PF was calculated using the counts of the dorsal view and compared with the calculated geometric mean [SQR(Ctsdors x Ctsventr)]. The differential function of the right kidney was significantly less when compared to the calculation of the geometric mean (p < 0.01). The mean difference between the PFgeom and the PFdors was 1.5 +/- 1.4%. A difference > or = 5% (5.0-9.5%) was obtained in only 6/164 scans (3.7%). Three of 6 patients presented with an underestimated PFdors due to dystopic kidneys on the left side in 2 patients and on the right side in one patient. The other 3 patients with a difference > 5% did not show any renal abnormality. The calculation of the PF from the posterior view only will give an underestimated value of the right kidney compared to the calculation of the geometric mean. This effect is not relevant for the calculation of the differential renal function in orthotopic kidneys, so that in these cases the anterior view is not necessary. However, geometric mean calculation to obtain reliable values for differential renal function should be applied in cases with an obvious anatomical abnormality.

[Imaging and follow-up of children with first febrile Urinary Tract Infection (UTI)].

PubMed

Grossman, Zachi; Miron, Dan

2009-10-01

Urinary tract infection (UTI) in children might, in a minority of cases, cause renal scarring and permanent damage. Known risk factors for renal damage are: obstruction to urinary flow, vesicoureteric reflux and recurrent infections. The current recommendations for imaging and follow-up of children with first febrile UTI include renal ultrasound to rule out anatomic abnormalities, particularly obstruction, cystography for possible diagnosis of vesicoureteric reflux, and prophylactic antibiotic therapy to prevent recurrent infections in children with detected reflux. DMSA renal scanning for the detection of renal scars is recommended as part of the imaging protocol by some institutions. Recently, published data doubts the importance of the various imaging techniques, as well as the effectiveness of prophylactic antibiotic therapy. In the current review, the role of renal ultrasound is examined, especially with regards to familiar data from fetal ultrasound. The complex relationship between vesicoureteric reflux and renal scarring is presented, with the possible implications on the importance of performing routine cystography and DMSA scanning after UTI. Studies questioning the effectiveness of prophylactic antibiotic therapy emphasize the importance of rapid diagnosis and therapy of suspected recurrent UTI as the preferred approach to prevent renal damage. Imaging studies are only recommended for high risk groups and not as a routine following UTI.

Magnetic resonance investigation of magnetic-labeled baker's yeast cells

NASA Astrophysics Data System (ADS)

Godoy Morais, J. P. M.; Azevedo, R. B.; Silva, L. P.; Lacava, Z. G. M.; Báo, S. N.; Silva, O.; Pelegrini, F.; Gansau, C.; Buske, N.; Safarik, I.; Safarikova, M.; Morais, P. C.

2004-05-01

In this study, the interaction of DMSA-coated magnetite nanoparticles (5 and 10 nm core-size) with Saccharomyces cerevisae was investigated using magnetic resonance (MR) and transmission electron microscopy (TEM). The TEM micrographs revealed magnetite nanoparticles attached externally to the cell wall. The MR data support the strong interaction among the nanoparticles supported by the cells. A remarkable shift in the resonance field was used as signature of particle attachment to the cell wall.

The presence of both horseshoe and a supernumerary kidney associated with coarctation of aorta.

PubMed

Unal, M; Erem, C; Serçe, K; Tuncer, C; Bostan, M; Gökçe, M

1995-01-01

Congenital urinary malformations associated with congenital heart disease are very rare. We present a case of horseshoe and supernumerary kidney associated with coarctation of aorta diagnosed by a combination of techniques of teleradiography, aortography, intravenous pyelography; ultrasonography, magnetic resonance imaging, and Dimercapto Succinic Acid (DMSA) and Diethylene Triamine Pentacetate (DTPA) imaging. This case represents the first reported instance of horseshoe and supernumerary kidney associated with coarctation of aorta.

Modeling the effect of succimer (DMSA; dimercaptosuccinic acid) chelation therapy in patients poisoned by lead.

PubMed

van Eijkeren, Jan C H; Olie, J Daniël N; Bradberry, Sally M; Vale, J Allister; de Vries, Irma; Clewell, Harvey J; Meulenbelt, Jan; Hunault, Claudine C

2017-02-01

Kinetic models could assist clinicians potentially in managing cases of lead poisoning. Several models exist that can simulate lead kinetics but none of them can predict the effect of chelation in lead poisoning. Our aim was to devise a model to predict the effect of succimer (dimercaptosuccinic acid; DMSA) chelation therapy on blood lead concentrations. We integrated a two-compartment kinetic succimer model into an existing PBPK lead model and produced a Chelation Lead Therapy (CLT) model. The accuracy of the model's predictions was assessed by simulating clinical observations in patients poisoned by lead and treated with succimer. The CLT model calculates blood lead concentrations as the sum of the background exposure and the acute or chronic lead poisoning. The latter was due either to ingestion of traditional remedies or occupational exposure to lead-polluted ambient air. The exposure duration was known. The blood lead concentrations predicted by the CLT model were compared to the measured blood lead concentrations. Pre-chelation blood lead concentrations ranged between 99 and 150 μg/dL. The model was able to simulate accurately the blood lead concentrations during and after succimer treatment. The pattern of urine lead excretion was successfully predicted in some patients, while poorly predicted in others. Our model is able to predict blood lead concentrations after succimer therapy, at least, in situations where the duration of lead exposure is known.

Combinational chelation therapy abrogates lead-induced neurodegeneration in rats.

PubMed

Pachauri, Vidhu; Saxena, Geetu; Mehta, Ashish; Mishra, Deepshikha; Flora, Swaran J S

2009-10-15

Lead, a ubiquitous and potent neurotoxicant causes oxidative stress which leads to numerous neurobehavioral and physiological alterations. The ability of lead to bind sulfhydryl groups or compete with calcium could be one of the reasons for its debilitating effects. In the present study, we addressed: i) if chelation therapy could circumvent the altered oxidative stress and prevent neuronal apoptosis in chronic lead-intoxicated rats, ii) whether chelation therapy could reverse biochemical and behavioral changes, and iii) if mono or combinational therapy with captopril (an antioxidant) and thiol chelating agents (DMSA/MiADMSA) is more effective than individual thiol chelator in lead-exposed rats. Results indicated that lead caused a significant increase in reactive oxygen species, nitric oxide, and intracellular free calcium levels along with altered behavioral abnormalities in locomotor activity, exploratory behavior, learning, and memory that were supported by changes in neurotransmitter levels. A fall in membrane potential, release of cytochrome c, and DNA damage indicated mitochondrial-dependent apoptosis. Most of these alterations showed significant recovery following combined therapy with captopril with MiADMSA and to a smaller extend with captopril+DMSA over monotherapy with these chelators. It could be concluded from our present results that co-administration of a potent antioxidant (like captopril) might be a better treatment protocol than monotherapy to counter lead-induced oxidative stress. The major highlight of the work is an interesting experimental evidence of the efficacy of combinational therapy using an antioxidant with a thiol chelator in reversing neurological dystrophy caused due to chronic lead exposure in rats.

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

Pachauri, Vidhu; Saxena, Geetu; Mehta, Ashish

Lead, a ubiquitous and potent neurotoxicant causes oxidative stress which leads to numerous neurobehavioral and physiological alterations. The ability of lead to bind sulfhydryl groups or compete with calcium could be one of the reasons for its debilitating effects. In the present study, we addressed: i) if chelation therapy could circumvent the altered oxidative stress and prevent neuronal apoptosis in chronic lead-intoxicated rats, ii) whether chelation therapy could reverse biochemical and behavioral changes, and iii) if mono or combinational therapy with captopril (an antioxidant) and thiol chelating agents (DMSA/MiADMSA) is more effective than individual thiol chelator in lead-exposed rats. Resultsmore » indicated that lead caused a significant increase in reactive oxygen species, nitric oxide, and intracellular free calcium levels along with altered behavioral abnormalities in locomotor activity, exploratory behavior, learning, and memory that were supported by changes in neurotransmitter levels. A fall in membrane potential, release of cytochrome c, and DNA damage indicated mitochondrial-dependent apoptosis. Most of these alterations showed significant recovery following combined therapy with captopril with MiADMSA and to a smaller extend with captopril + DMSA over monotherapy with these chelators. It could be concluded from our present results that co-administration of a potent antioxidant (like captopril) might be a better treatment protocol than monotherapy to counter lead-induced oxidative stress. The major highlight of the work is an interesting experimental evidence of the efficacy of combinational therapy using an antioxidant with a thiol chelator in reversing neurological dystrophy caused due to chronic lead exposure in rats.« less

Different cell responses induced by exposure to maghemite nanoparticles.

PubMed

Luengo, Yurena; Nardecchia, Stefania; Morales, María Puerto; Serrano, M Concepción

2013-12-07

Recent advances in nanotechnology have permitted the development of a wide repertoire of inorganic magnetic nanoparticles (NPs) with extensive promise for biomedical applications. Despite this remarkable potential, many questions still arise concerning the biocompatible nature of NPs when in contact with biological systems. Herein, we have investigated how controlled changes in the physicochemical properties of iron oxide NPs at their surface (i.e., surface charge and hydrodynamic size) affect, first, their interaction with cell media components and, subsequently, cell responses to NP exposure. For that purpose, we have prepared iron oxide NPs with three different coatings (i.e., dimercaptosuccinic acid - DMSA, (3-aminopropyl)triethoxysilane - APS and dextran) and explored the response of two different cell types, murine L929 fibroblasts and human Saos-2 osteoblasts, to their exposure. Interestingly, different cell responses were found depending on the NP concentration, surface charge and cell type. In this sense, neutral NPs, as those coated with dextran, induced negligible cell damage, as their cellular internalization was significantly reduced. In contrast, surface-charged NPs (i.e., those coated with DMSA and APS) caused significant cellular changes in viability, morphology and cell cycle under certain culture conditions, as a result of a more active cellular internalization. These results also revealed a particular cellular ability to detect and remember the original physicochemical properties of the NPs, despite the formation of a protein corona when incubated in culture media. Overall, conclusions from these studies are of crucial interest for future biomedical applications of iron oxide NPs.

Evaluation of nickel ferrite nanoparticles coated with oleylamine by NMR relaxation measurements and magnetic hyperthermia.

PubMed

Menelaou, M; Georgoula, K; Simeonidis, K; Dendrinou-Samara, C

2014-03-07

Nickel ferrite nanoparticles were synthesized via a facile solvothermal approach. Oleylamine (OAm) was used in all synthetic procedures as a stabilizing agent and solvent. By varying the polarity of the solvents, hydrophobic NiFe2O4 nanoparticles coated with OAm of relatively similar sizes (9-11.7 nm) and in a range of magnetization values (32.0-53.5 emu g(-1)) were obtained. The as-prepared hydrophobic nanoparticles were characterized by XRD, TEM, SEM, TGA and VSM and converted to hydrophilic by two different approaches. The addition of a positively charged ligand (cetyltrimethyl ammonium bromide, CTAB) and the ligand exchange procedure (2,3-dimercaptosuccinic acid, DMSA) have been successfully applied. The aqueous suspensions of NiFe2O4@CTAB and NiFe2O4@DMSA showed good colloidal stability after a long period of time. The different surface modification affected both the NMR relaxometric measurements and the hyperthermia effects. In both techniques CTAB modification demonstrated higher r2 relaxivity (278.9 s(-1) mM(-1) in an NMR spectrometer at 11.7 T) and SAR values (423.4 W g(-1) at an applied AC field with a particle concentration of 0.5 mg mL(-1)). The results indicate that a coating with a larger molecule as CTAB under the same size, shape and magnetization of NiFe2O4 NPs gave rise to NMR relaxometric properties and heating efficacy.

The impact of therapeutic delay time on acute scintigraphic lesion and ultimate scar formation in children with first febrile UTI.

PubMed

Oh, Mi Mi; Kim, Jin Wook; Park, Min Gu; Kim, Je Jong; Yoo, Kee Hwan; Moon, Du Geon

2012-03-01

We assessed the role of therapeutic delay time (TDT) in acute renal cortical scintigraphic lesion (ASL) and ultimate scar formation (USF) in children with first febrile UTI and whether it is affected by the presence of vesico-ureteral reflux (VUR). 230 children, 90 girls and 140 boys with first febrile UTI were included. Radiologic (USG, DMSA, and VCUG), clinical (age, gender, peak fever, therapeutic delay time) and laboratory (CBC with differential count, ANC (absolute neutrophil count), BUN, Creatinine, urine analysis, gram stain, culture, CRP and ESR) variables were analysed. DMSA was performed within 5 days and after six months. VCUG was performed after acute phase of UTI. The differences in TDT according to the presence of ASL, USF and VUR were assessed. And the correlation between ASL or USF with the duration of TDT was assessed. Of 230 patients enrolled, 142 patients had refluxing UTI and 88 patients had non-refluxing UTI. TDT was the risk factor associated with ASL and USF along with presence of VUR. TDT was longer in ASL positive group compared with the ASL negative group. Also USF group showed longer TDT compared with those without USF in both refluxing UTI and non refluxing UTI. The TDT was significantly shorter in USF group with the presence of VUR. Positive linear association was noted between prevalence of ASL and USF and duration of TDT. In conclusion, the impact of UTI on formation of USF may be enhanced by the presence of VUR with shorter duration of TDT.

A review of pitfalls and progress in chelation treatment of metal poisonings.

PubMed

Andersen, Ole; Aaseth, Jan

2016-12-01

Most acute and chronic human metal poisonings are due to oral or inhalation exposure. Almost 80% of published animal experiments on chelation in metal poisoning used single or repeated intraperitoneal, intramuscular or intravenous administration of metal and chelator, impeding extrapolation to clinical settings. Intramuscular administration of dimercaptopropanol (BAL) has until now been used in acute arsenic, lead, and mercury poisonings, but repeated BAL administration increased the brain uptake of As, Pb and Hg in experimental animals. Also, diethyl dithiocarbamate (DDC) has been used as antidote in acute experimental animal parenteral Cd poisoning, and both DDC and tetraethylthiuram disulfide (TTD, disulfiram, Antabuse) have been used in nickel allergic patients. However, even one dose of DDC given immediately after oral Cd or Ni increased their brain uptake considerably. The calcium salt of ethylenediamminetetraacetic acid (CaEDTA) but not dimercaptosuccinic acid (DMSA) increased the brain uptake of Pb. In oral Cd or Hg poisoning, early oral administration of DMSA or dimercaptopropane sulfonate (DMPS) increased survival and reduced intestinal metal uptake. Oral administration of Prussian Blue or resins with fixed chelating groups that are not absorbed offer chelation approaches for decorporation after oral exposure to various metals. Diethylenetriaminepentaacetic acid (DTPA) nebulizers for pulmonary chelation after inhalation exposure need further development. Also, combined chelation with more than one compound may offer extensive advances. Solid knowledge on the chemistry of metal chelates together with relevant animal experiments should guide development of chelation procedures to alleviate and not aggravate the clinical status of poisoned patients. Copyright © 2016 Elsevier GmbH. All rights reserved.

Urinary tract infection in small children: the evolution of renal damage over time.

PubMed

Swerkersson, Svante; Jodal, Ulf; Sixt, Rune; Stokland, Eira; Hansson, Sverker

2017-10-01

Our objective was to analyze the evolution of kidney damage over time in small children with urinary tract infection (UTI) and factors associated with progression of renal damage. From a cohort of 1003 children <2 years of age with first-time UTI, a retrospective analysis of 103 children was done. Children were selected because of renal damage at index 99m Tc-dimercaptosuccinic acid (DMSA) scintigraphy at least 3 months after UTI, and a late DMSA scan was performed after at least 2 years. Damage was classified as progression when there was a decline in differential renal function (DRF) by ≥4%, as regression when there was complete or partial resolution of uptake defects. Of 103 children, 20 showed progression, 20 regression, and 63 remained unchanged. There were no differences between groups regarding gender or age. In the progression group, 16/20 (80%) children had vesicoureteral reflux (VUR) grade III-V and 13 (65%) had recurrent UTI. In multivariable regression analysis, both VUR grade III-V and recurrent UTI were associated with progression. In the regression group, 16/20 (80%) had no VUR or grade I-II, and two (10%) had recurrent UTI. Most small children with febrile UTI do not develop renal damage and if they do the majority remain unchanged or regress over time. However, up to one-fifth of children with renal damage diagnosed after UTI are at risk of renal deterioration. These children are characterized by the presence of VUR grades III-V and recurrent febrile UTI and may benefit from follow-up.

Structural characterization of 1,3-propanedithiols that feature carboxylic acids: Homologues of mercury chelating agents ✩

PubMed Central

Sattler, Wesley; Palmer, Joshua H.; Bridges, Christy C.; Joshee, Lucy; Zalups, Rudolfs K.; Parkin, Gerard

2013-01-01

The molecular structures of a series of 1,3-propanedithiols that contain carboxylic acid groups, namely rac- and meso-2,4-dimercaptoglutaric acid (H4DMGA) and 2-carboxy-1,3-propanedithiol (H3DMCP), have been determined by X-ray diffraction. Each compound exhibits two centrosymmetric intermolecular hydrogen bonding interactions between pairs of carboxylic acid groups, which result in a dimeric structure for H3DMCP and a polymeric tape-like structure for rac- and meso-H4DMGA. Significantly, the hydrogen bonding motifs observed for rac- and meso-H4DMGA are very different to those observed for the 1,2-dithiol, rac-2,3-dimercaptosuccinic acid (rac-H4DMSA), in which the two oxygen atoms of each carboxylic acid group hydrogen bond to two different carboxylic acid groups, thereby resulting in a hydrogen bonded sheet-like structure rather than a tape. Density functional theory calculations indicate that 1,3-dithiolate coordination to mercury results in larger S–Hg–S bond angles than does 1,2-dithiolate coordination, but these angles are far from linear. As such, κ2-S2 coordination of these dithiolate ligands is expected to be associated with mercury coordination numbers of greater than two. In vivo studies demonstrate that both rac-H4DMGA and H3DMCP reduce the renal burden of mercury in rats, although the compounds are not as effective as either 2,3-dimercaptopropane-1-sulfonic acid (H3DMPS) or meso-H4DMSA. PMID:24187425

The role of fetal-maternal microchimerism as a natural-born healer in integrity improvement of maternal damaged kidney.

PubMed

Kajbafzadeh, Abdol-Mohammad; Sabetkish, Shabnam; Sabetkish, Nastaran

2018-01-01

To identify the fetal stem cell (FSC) response to maternal renal injury with emphasis on renal integrity improvement and Y chromosome detection in damaged maternal kidney. Eight non-green fluorescent protein (GFP) transgenic Sprague- Dawley rats were mated with GFP-positive transgenic male rats. Renal damage was induced on the right kidney at gestational day 11. The same procedure was performed in eight non-pregnant rats as control group. Three months after delivery, right nephrectomy was performed in order to evaluate the injured kidney. The fresh perfused kidneys were stained with anti-GFP antibody. Polymerase chain reaction (PCR) assay was also performed for the Y chromosome detection. Cell culture was performed to detect the GFP-positive cells. Technetium-99m-DMSA renal scan and single-photon emission computed tomography (SPECT) were performed after renal damage induction and 3 months later to evaluate the improvement of renal integrity. The presence of FSCs was confirmed by immune histochemical staining as well as immunofluorescent imaging of the damaged part. Gradient PCR of female rat purified DNA demonstrated the presence of Y-chromosome in the damaged maternal kidney. Moreover, the culture of kidney cells showed GPF- positive cells by immunofluorescence microscopy. The acute renal scar was repaired and the integrity of damaged kidney reached to near normal levels in experimental group as shown in DMSA scan. However, no significant improvement was observed in control group. FSC seems to be the main mechanism in repairing of the maternal renal injury during pregnancy as indicated by Y chromosome and GFP-positive cells in the sub-cultured medium. Copyright® by the International Brazilian Journal of Urology.

99mTc-EDDA/HYNIC-TOC in the management of medullary thyroid carcinoma.

PubMed

Parisella, Maria; D'Alessandria, Calogero; van de Bossche, Bieke; Chianelli, Marco; Ronga, Giuseppe; Papini, Enrico; Mikolajczak, Renata; Letizia, Claudio; De Toma, Giorgio; Veneziani, Augusto; Scopinaro, Francesco; Signore, Alberto

2004-04-01

An early diagnosis of distant metastases or local recurrences of medullary thyroid carcinoma (MTC) can be achieved by several conventional radiological modalities (e.g., ultrasonography, computed tomography [CT], and magnetic resonance imaging [MRI] as well as by radioisotopic procedures, such as positron emission tomography (PET), scintigraphy with different types of radiopharmaceuticals, and radiolabeled receptor-ligands in particular. The aim of this study was to evaluate the clinical utility of 99mTc-EDDA/HYNIC-TOC, a new octreotide derivative, to detect recurrences of disease or distant metastases in MTC. Images obtained of 5 patients with high levels of serum calcitonin were compared to findings obtained with other diagnostic procedures: 111In-octreotide, 99mTc-DMSA-V, 18F-flouro-D-deoxyglucose-PET, and CT/MRI. 99mTc-EDDA/HYNIC-TOC was positive in all patients and showed 15 areas of pathological uptake in the cervical and mediastinal regions. 111In-octreotide was positive in 3 of 3 patients and showed 4 areas, compared to 8 of 99mTc-EDDA/HYNIC-TOC. 99mTc-V-DMSA was positive in 3 of 4 patients but showed 6 pathological areas, compared to 13 of 99mTc-EDDA/HYNIC-TOC. 18F-FDG-PET was positive in 5 of 5 patients but showed only 11 areas, compared to 15 of 99mTc-EDDA/HYNIC-TOC. The CT scan was positive in only 2 patients. In conclusion, 99mTc-EDDA/HYNIC-TOC detected more sites of pathological uptake than other modalities, showed better imaging properties than 111In-octreotide, and might be the radiopharmaceutical of choice for providing a rationale for radioisotopic therapy.

A safe strategy to decrease fetal lead exposure in a woman with chronic intoxication.

PubMed

Leiba, Adi; Hu, Howard; Zheng, Amin; Kales, Stefanos N

2010-08-01

During pregnancy skeletal lead is mobilized by maternal bone turnover and can threaten fetal development. The exact strategy suggested to women of childbearing age, who were chronically exposed to lead, and, thus, have high bone lead burden, is not well established. We describe 4 years of follow-up of a 29-year-old woman with chronic lead intoxication. We (a) advised her to delay conception until 'toxicological clearance', (b) treated her with multiple courses of lead chelator, DMSA, and (c) prescribed oral calcium. Patient had low blood lead and protoporphyrin level during pregnancy until delivery. Delaying conception, lead chelation, and calcium supplementation can decrease fetal exposure.

Williams-Beuren syndrome associated with single kidney and nephrocalcinosis: a case report.

PubMed

Abidi, Kamel; Jellouli, Manel; Ben Rabeh, Rania; Hammi, Yousra; Gargah, Tahar

2015-01-01

Williams-Beuren syndrome is a rare neurodevelopmental disorder, characterized by congenital heart defects, abnormal facial features, mental retardation with specific cognitive and behavioral profile, growth hormone deficiency, renal and skeletal anomalies, inguinal hernia, infantile hypercalcaemia. We report a case with Williams-Beuren syndrome associated with a single kidney and nephrocalcinosis complicated by hypercalcaemia. A male infant, aged 20 months presented growth retardation associated with a psychomotor impairment, dysmorphic features and nephrocalcinosis. He had also hypercalciuria and hypercalcemia. Echocardiography was normal. DMSA renal scintigraphy showed a single functioning kidney. The FISH generated one ELN signal in 20 metaphases read and found the presence of ELN deletion, with compatible Williams-Beuren syndrome.

Post-elution concentration of (188)Re by an electrochemical method.

PubMed

Chakravarty, Rubel; Dash, Ashutosh; Pillai, M R A; Venkatesh, Meera

2010-12-01

High specific activity (188)Re required for nuclear medicine is mostly obtained from (188)W/(188)Re generators. As the parent radionuclide (188)W is of low specific activity (<185 GBq/g), a relatively large volume of 0.9% saline is required for the elution of (188)Re. Post-elution concentration is needed in order to increase the radioactive concentration of the eluted (188)Re. An electrochemical procedure to concentrate (188)Re suitable for the preparation of radiopharmaceuticals is developed. (188)Re eluted from an alumina generator could be concentrated approximately 100 fold, and it could be used to label DMSA and HEDP with >98% yield. Copyright 2010 Elsevier Ltd. All rights reserved.

Role of scintigraphy in urinary tract infection

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

Conway, J.J.

1988-10-01

There is controversy regarding the role of radiological imaging for urinary tract infection (UTI). The gold standard has been the intravenous pyelogram (IVP). Yet, the IVP has a very limited value with only about 25% of children with pyelonephritis demonstrating abnormalities. Ultrasound (US) has recently been advocated as a replacement for the poorly sensitive and poorly specific IVP. However, comparative studies between US and IVP indicate only an equivalent sensitivity and specificity. Cortical scintigraphy with Technetium-99m glucoheptonate (99mTc GH) or 99mTc dimercaptosuccinic acid (99mTc DMSA) has also been advocated as a means of differentiating parenchymal (pyelonephritis) from nonparenchymal (lower UTI)more » involvement in UTI. The clinical presentation may be misleading especially in the infant and child in whom an elevated temperature, flank pain, shaking chills, or an elevated sedimentation rate are often lacking. The clinician attempts to localize the site of infection for it has a direct bearing upon the therapy. A collecting system infection can often be eradicated with a single oral dose of an appropriate antibiotic, whereas renal parenchymal involvement requires IV therapy for an extended interval. Cortical scintigraphy can localize the site of infection with a high degree of accuracy. Recent studies report a sensitivity of 86% and specificity of 81% of pyelonephritis. This is in contrast to the IVP with a sensitivity of only 24% and US with a sensitivity of only 42%. The scintigraphic appearance of parenchymal infection of the kidney is a spectrum of minimal to gross defects reflecting the degree of histologic involvement that spans from a mild infection to frank abscess. Cortical scintigraphy can be used to monitor the evolution of scarring following infection. Cortical scintigraphy with 99mTc DMSA or 99mTc GH is the method of choice for the initial evaluation of UTI. 37 references.« less

[Should morphology of the upper pole in renal duplication with preserved function and associated ureterocele be taken into account during treatment planning?].

PubMed

Materny, Jacek; Chojnacka, Hanna; Urasińska, Elzbieta; Gawrych, Elzbieta

2011-01-01

The aim of this study was to assess structural changes of the upper pole in renal duplication with coexisting ureterocele with regard to primary and/or secondary lesions. These changes might be of importance in treatment planning. The material of this study consisted of clinical documentation and results of histopathology of 23 upper poles removed due to renal duplication with coexisting ureterocele. The qualification criterion was preserved function of the upper pole seen with 99mTc-DTPA (99mTechnetium diethylenetriaminepentaacetic acid)/99mTc-DMSA (99mTechnetium dimercaptosuccinic acid). Resection of the upper pole was indicated in patients with recurrent urinary tract infections and/or persistent vesicoureteral reflux to the lower pole following endoscopic surgery of the ureterocele and/or low function of the upper pole. Morphological lesions were classified as primary (dysplasia) or secondary lesions. The patients were operated at the Department of Pediatric and Oncologic Surgery, PMU, in 1990-2008. The study group consisted of 17 girls and 6 boys aged from 4 months to 9 years (mean 40 months). Recurrent urinary tract infections noted in 16 (70%) children were the most frequent indication for surgery. The preoperative mean function of the renal poles assessed with DTPA/DMSA represented 6% of the differential renal function. Dysplasia was identified in eight resected renal poles (34%) with coexisting secondary lesions in three of them. Secondary lesions only were seen in 15 poles (66%). There was no correlation between age and incidence of dysplasia during follow-up (Pearson's correlation coefficient r = 0.031). Secondary lesions are a quite frequent finding in resected upper poles. As 66% of the renal poles studied with histopathology revealed secondary lesions only, we believe that renal sparing treatment is justified in cases of urinary duplication with coexisting ureterocele.

Symptomatic urinary tract infection in preschool Australian children.

PubMed

Craig, J C; Irwig, L M; Knight, J F; Sureshkumar, P; Roy, L P

1998-04-01

To describe the demographic and clinical features, short-term outcomes, microbiology and renal tract abnormalities of a cohort of young Australian children with symptomatic urinary tract infection. A total of 304 children < 5 years with their first documented symptomatic urinary tract infection who presented consecutively to the Emergency Department of a paediatric hospital between March 1993 and December 1994 and without a known predisposing cause were identified and details of their acute illness were recorded. Renal tract sonography, micturating cystourethrography and Tc-99 m dimercaptosuccinic acid scintigraphy (DMSA) were routinely performed. Of those who presented with urinary tract infection, 169 were boys and 135 girls; 64% were less than 1 year of age. For children from the local community, the cumulative incidence of urinary tract infection within the first 5 years of life was estimated to be 1.9% for boys and 1.8% for girls. There were no significant differences in illness characteristics according to mode of referral or geographical locality. Presenting symptoms were generally nonspecific and not referrable to the urinary tract. There were no deaths. One per cent of children required ventilatory support, and bacteraemia occurred in 6%, all of whom were under 6 months of age. E. coli was the causal organism in 84%, and a high in vitro resistance to ampicillin/ amoxycillin (54%) was demonstrated by the pathogens isolated. Bacteriuria was eradicated in 99% with antimicrobial treatment. In this setting, the sensitivities of dipstick urinalysis (leucocyte esterase+/-nitrites) and pyuria on microscopy (>10 x 10(6) white cells L(-1)) were 85%. Abnormal DMSA scintigraphy was detected in 39%, vesicoureteric reflux in 28%, and obstructive uropathy in 1%. This study provides current and local data on a large sample of children <5 years with urinary tract infection, which are useful to clinicians who manage children at risk of the condition.

Cysteine analogues potentiate glucose-induced insulin release in vitro

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

Ammon, H.P.; Hehl, K.H.; Enz, G.

1986-12-01

In rat pancreatic islets, cysteine analogues, including glutathione, acetylcysteine, cysteamine, D-penicillamine, L-cysteine ethyl ester, and cysteine-potentiated glucose (11.1 mM) induced insulin secretion in a concentration-dependent manner. Their maximal effects were similar and occurred at approximately 0.05, 0.05, 0.1, 0.5, 1.0, 1.0 mM, respectively. At substimulatory glucose levels (2.8 mM), insulin release was not affected by these compounds. In contrast, thiol compounds, structurally different from cysteine and its analogues, such as mesna, tiopronin, meso-2,3-dimercaptosuccinic acid (DMSA), dimercaprol (BAL), beta-thio-D-glucose, as well as those cysteine analogues that lack a free-thiol group, including L-cystine, cystamine, D-penicillamine disulfide, S-carbocysteine, and S-carbamoyl-L-cysteine, did not enhancemore » insulin release at stimulatory glucose levels (11.1 mM); cystine (5 mM) was inhibitory. These in vitro data indicate that among the thiols tested here, only cysteine and its analogues potentiate glucose-induced insulin secretion, whereas thiols that are structurally not related to cysteine do not. This suggests that a cysteine moiety in the molecule is necessary for the insulinotropic effect. For their synergistic action to glucose, the availability of a sulfhydryl group is also a prerequisite. The maximal synergistic action is similar for all cysteine analogues tested, whereas the potency of action is different, suggesting similarity in the mechanism of action but differences in the affinity to the secretory system.« less

The effect of core and lanthanide ion dopants in sodium fluoride-based nanocrystals on phagocytic activity of human blood leukocytes

NASA Astrophysics Data System (ADS)

Sojka, Bartlomiej; Liskova, Aurelia; Kuricova, Miroslava; Banski, Mateusz; Misiewicz, Jan; Dusinska, Maria; Horvathova, Mira; Ilavska, Silvia; Szabova, Michaela; Rollerova, Eva; Podhorodecki, Artur; Tulinska, Jana

2017-02-01

Sodium fluoride-based β-NaLnF4 nanoparticles (NPs) doped with lanthanide ions are promising materials for application as luminescent markers in bio-imaging. In this work, the effect of NPs doped with yttrium (Y), gadolinium (Gd), europium (Eu), thulium (Tm), ytterbium (Yb) and terbium (Tb) ions on phagocytic activity of monocytes and granulocytes and the respiratory burst was examined. The surface functionalization of <10-nm NPs was performed according to our variation of patent pending ligand exchange method that resulted in meso-2,3-dimercaptosuccinic acid (DMSA) molecules on their surface. Y-core-based NCs were doped with Eu ions, which enabled them to be excited with UV light wavelengths. Cultures of human peripheral blood ( n = 8) were in vitro treated with five different concentrations of eight NPs for 24 h. In summary, neither type of nanoparticles is found toxic with respect to conducted test; however, some cause toxic effects (they have statistically significant deviations compared to reference) in some selected doses tested. Both core types of NPs (Y-core and Gd-core) impaired the phagocytic activity of monocytes the strongest, having minimal or none whatsoever influence on granulocytes and respiratory burst of phagocytic cells. The lowest toxicity was observed in Gd-core, Yb, Tm dopants and near-infrared nanoparticles. Clear dose-dependent effect of NPs on phagocytic activity of leukocytes and respiratory burst of cells was observed for limited number of samples.

Value of diuresis renography in the post-natal period of assumed physiological renal immaturity.

PubMed

Eising, E G; Bonzel, K E; Zander, C; Farahati, J; Reiners, C

1997-11-01

The aim of this study was to determine if it is possible to exclude renal obstruction using diuresis renography in the first 6 weeks of life (the period of physiological renal immaturity), thus avoiding unnecessary invasive procedures, such as the Whitaker test or surgery. Diuresis renography with 123I-hippuran was performed in 27 patients aged less than 6 weeks and in 50 older children who acted as a reference group (age 6 weeks to 1 year, n = 28; age 1-10 years, n = 22). All 27 patients had significant dilatation of the pelvicalyceal system on ultrasonography. Renal curves were evaluated by mathematical curve characteristics (split renal function, counts, T-max, etc.) as the visual grade of obstruction. Whole-kidney regions of interest were defined on images summed over 30 min; renal parenchyma on images summed over 5 min. The renal curves of 18/27 patients indicated tracer accumulation and led to frusemide administration. Only two patients showed no significant response to frusemide and had to be further investigated by the Whitaker test. The frequency of kidneys with no response to frusemide revealed no significant differences in the three groups. Whole-kidney evaluation resulted in an overestimation of obstruction in 9/150 kidneys, which matches the lower correlation to the DMSA separation values for this method of evaluation. In contrast with the literature, significant post-renal obstruction can be excluded by diuresis renography in most cases in spite of renal immaturity and can help to avoid invasive procedures.

Controversies Regarding Management of Vesico-ureteric Reflux.

PubMed

Babu, Ramesh; Chowdhary, Sujit

2017-07-01

The primary goal in the management of a child with urinary tract infection (UTI) is to prevent recurrence of UTI and acquired renal damage. Approximately 15% of children develop renal scarring after a first episode of febrile UTI. Vesico-ureteric reflux (VUR) is diagnosed in 30-40% of children imaged after first febrile UTI. The 'top-down' approach involving ultrasound and dimercaptosuccinic acid scan (DMSA) first after an appropriate interval following UTI, can help in avoiding voiding cystourethrogram (VCUG), an invasive test with higher radiation exposure. The majority view remains that VCUG should be done after the second attack of UTI in girls and first attack of UTI in boys. Although the evidence in favour of antibiotic prophylaxis remains doubtful in preventing renal scars associated with VUR, it remains the first line treatment for high-grade reflux (grade 3-5) with an aim to prevent UTI and allow spontaneous resolution of VUR. Early identification and appropriate treatment of associated bowel bladder dysfunction is an essential part of successful medical management of VUR. Endoscopic treatment of VUR, using a bulking agent, is useful in grade 3 VUR. The main controversy regarding intervention (endoscopic/open surgical intervention) involves absence of strong evidence for these interventions in reducing renal scarring on randomized controlled trials. However, several recent trials have found the surgical interventions to be effective in reducing recurrent pyelonephritis and repeated hospital admissions.

Assessment of organotin and tin-free antifouling paints contamination in the Korean coastal area.

PubMed

Lee, Mi-Ri-Nae; Kim, Un-Jung; Lee, In-Seok; Choi, Minkyu; Oh, Jeong-Eun

2015-10-15

Twelve organotins (methyl-, octyl-, butyl-, and phenyl-tin), and eight tin-free antifouling paints and their degradation products were measured in marine sediments from the Korean coastal area, and Busan and Ulsan bays, the largest harbor area in Korea. The total concentration of tin-free antifouling paints was two- to threefold higher than the total concentration of organotins. Principal component analysis was used to identify sites with relatively high levels of contamination in the inner bay area of Busan and Ulsan bays, which were separated from the coastal area. In Busan and Ulsan bays, chlorothalonil and DMSA were more dominant than in the coastal area. However, Sea-Nine 211 and total diurons, including their degradation products, were generally dominant in the Korean coastal area. The concentrations of tin and tin-free compounds were significantly different between the east and west coasts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Role of nuclear medicine in clinical urology and nephrology

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

Blaufox, M.D.; Fine, E.; Lee, H.B.

The application of radionuclide studies to nephrologic and urologic practice has reached a measurable degree of maturity during the past several years. In spite of this, the utilization of these techniques in many institutions in the United States continues to be far less frequent than one would expect from the clinical advantages. The aim of this editorial is to try to place the role of nuclear medicine in urology and nephrology in perspective. At the present time, in spite of the large number of renal agents that have been developed, there is no practical ideal radiopharmaceutical that can serve asmore » a universal agent. Arbitrarily, one may reduce the chief armamentarium to only four radiopharmaceuticals; technetium-99m DTPA, I-131 OIH (orthoiodohippurate), technetium-99m glucoheptonate and technetium-99m DMSA. These agents are discussed with their relative advantages and disadvantages.« less

Molecular imaging in neuroendocrine tumors: molecular uptake mechanisms and clinical results.

PubMed

Koopmans, Klaas P; Neels, Oliver N; Kema, Ido P; Elsinga, Philip H; Links, Thera P; de Vries, Elisabeth G E; Jager, Pieter L

2009-09-01

Neuroendocrine tumors can originate almost everywhere in the body and consist of a great variety of subtypes. This paper focuses on molecular imaging methods using nuclear medicine techniques in neuroendocrine tumors, coupling molecular uptake mechanisms of radiotracers with clinical results. A non-systematic review is presented on receptor based and metabolic imaging methods. Receptor-based imaging covers the molecular backgrounds of somatostatin, vaso-intestinal peptide (VIP), bombesin and cholecystokinin (CCK) receptors and their link with nuclear imaging. Imaging methods based on specific metabolic properties include meta-iodo-benzylguanide (MIBG) and dimercapto-sulphuric acid (DMSA-V) scintigraphy as well as more modern positron emission tomography (PET)-based methods using radio-labeled analogues of amino acids, glucose, dihydroxyphenylalanine (DOPA), dopamine and tryptophan. Diagnostic sensitivities are presented for each imaging method and for each neuroendocrine tumor subtype. Finally, a Forest plot analysis of diagnostic performance is presented for each tumor type in order to provide a comprehensive overview for clinical use.

[Multilocus Sequence Typing analysis of human Campylobacter coli in Granada (Spain)].

PubMed

Carrillo-Ávila, J A; Sorlózano-Puerto, A; Pérez-Ruiz, M; Gutiérrez-Fernández, J

2016-12-01

Different subtypes of Campylobacter spp. have been associated with diarrhoea and a Multilocus Sequence Typing (MLST) method has been performed for subtyping. In the present work, MLST was used to analyse the genetic diversity of eight strains of Campylobacter coli. Nineteen genetic markers were amplified for MLST analysis: AnsB, DmsA, ggt, Cj1585c, CJJ81176-1367/1371, Tlp7, cj1321-cj1326, fucP, cj0178, cj0755/cfrA, ceuE, pldA, cstII, cstIII. After comparing the obtained sequences with the Campylobacter MLST database, the allele numbers, sequence types (STs) and clonal complexes (CCs) were assigned. The 8 C. coli isolates yielded 4 different STs belonging to 2 CCs. Seven isolates belong to ST-828 clonal complex and only one isolate belong to ST-21. Two samples came from the same patient, but were isolated in two different periods of time. MLST can be useful for taxonomic characterization of C. coli isolates.

The role of overweight and obesity in urinary tract infection in children.

PubMed

Mahyar, Abolfazl; Ayazi, Parviz; Gholmohammadi, Parisa; Moshiri, Seyed Alireza; Oveisi, Sonia; Esmaeily, Shiva

2016-01-01

This study was conducted to determine the relationship between overweight/obesity and UTI in children. A comparison was made, in terms of overweight and obesity, between 135 children with UTI (case group) and 135 healthy children (control group). UTI was diagnosed through urine culture. Dimercaptosuccinic acid renal scanning (DMSA) was also used to distinguish between lower UTI and acute pyelonephritis. Overweight and obesity were determined based on standard body mass index (BMI) curves. There were 12 (8.8%) overweight and 26 (19.2%) obese children in the case group. Four (3.0%) overweight and five (3.7%) obese children were found in the control group. There was a significant difference between the two groups regarding overweight and obesity frequencies. However, no such difference existed between children with cystitis and acute pyelonephritis. This study showed a significant relationship between overweight/obesity and UTI. Therefore, overweight and obesity may play a role in the pathogenesis of UTI in children.

Renal tract abnormalities missed in a historical cohort of young children with UTI if the NICE and AAP imaging guidelines were applied.

PubMed

Narchi, Hassib; Marah, Muhaned; Khan, Asad Aziz; Al-Amri, Abdulla; Al-Shibli, Amar

2015-10-01

In a historical cohort of children with a urinary tract infection (UTI) who had already undergone all the imaging procedures, the aim was to determine renal tract abnormalities which would have been missed had we implemented the new guidelines from the National Institute for Health and Care Excellence in the United Kingdom (NICE) or the American Academy of Pediatrics (AAP). After a UTI episode, forty-three children (28 females, 65%) aged between 2 months and 2 years presenting at two general hospitals with a febrile UTI before 2008 underwent all the recommended imaging studies predating the new guidelines. Hydronephrosis was defined and graded according to the Society for Fetal Urology (SFU) classification. Hydronephrosis grade II (mild pelvicalyceal dilatation), grade III (moderate dilatation), and grade IV (gross dilatation with thinning of the renal cortex), duplication, vesicoureteral reflux (VUR) grade II and above, renal scarring and reduced renal uptake (<45%) on technetium-99m-labeled dimercaptosuccinic acid (DMSA) scintigraphy were considered significant abnormalities. We calculated the proportion of abnormalities which would have been missed had the new guidelines been used instead. The median of age was 7.6 months (mean 8.7, range 2-24 months), with the majority (n = 37, 86%) being under 1 year of age. Ultrasound (US) showed hydronephrosis in 14 (32%), all grade II. A voiding cystourethrogram (VCUG) was performed in all and showed VUR ≥ grade II in 16 (37%), including eight children (19%) where it was bilateral. DMSA scan showed scarring in 25 children (58%) of whom 11 (26%) had bilateral scars. Reduced differential renal uptake was present in 10 children (23%). Of the 29 children with normal US, 18 (62%) had renal scarring and nine (31%) had VUR ≥ grade II. The NICE guidelines would have missed 63% of the children with VUR ≥ grade II, including a high proportion of grades IV and V VUR, 44% of the children with renal scarring, and 20% of the children with decreased renal uptake, including some children with bilateral renal scarring and with decreased renal uptake. The AAP guidelines would have missed 56% of the children with VUR ≥ grade II, including a high proportion of grades IV and V VUR, and all children with renal scarring as well as those with decreased renal uptake. The prevalence of renal tract abnormalities missed by the new guidelines is high. They should be used with full awareness of their limitations. Copyright © 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Contribution of Auger/conversion electrons to renal side effects after radionuclide therapy: preclinical comparison of (161)Tb-folate and (177)Lu-folate.

PubMed

Haller, Stephanie; Pellegrini, Giovanni; Vermeulen, Christiaan; van der Meulen, Nicholas P; Köster, Ulli; Bernhardt, Peter; Schibli, Roger; Müller, Cristina

2016-12-01

The radiolanthanide (161)Tb has, in recent years, attracted increasing interest due to its favorable characteristics for medical application. (161)Tb exhibits similar properties to the widely-used therapeutic radionuclide (177)Lu. In contrast to (177)Lu, (161)Tb yields a significant number of short-ranging Auger/conversion electrons (≤50 keV) during its decay process. (161)Tb has been shown to be more effective for tumor therapy than (177)Lu if applied using the same activity. The purpose of this study was to investigate long-term damage to the kidneys after application of (161)Tb-folate and compare it to the renal effects caused by (177)Lu-folate. Renal side effects were investigated in nude mice after the application of different activities of (161)Tb-folate (10, 20, and 30 MBq per mouse) over a period of 8 months. Renal function was monitored by the determination of (99m)Tc-DMSA uptake in the kidneys and by measuring blood urea nitrogen and creatinine levels in the plasma. Histopathological analysis was performed by scoring of the tissue damage observed in HE-stained kidney sections from euthanized mice. Due to the co-emitted Auger/conversion electrons, the mean absorbed renal dose of (161)Tb-folate (3.0 Gy/MBq) was about 24 % higher than that of (177)Lu-folate (2.3 Gy/MBq). After application of (161)Tb-folate, kidney function was reduced in a dose- and time-dependent manner, as indicated by the decreased renal uptake of (99m)Tc-DMSA and the increased levels of blood urea nitrogen and creatinine. Similar results were obtained when (177)Lu-folate was applied at the same activity. Histopathological investigations confirmed comparable renal cortical damage after application of the same activities of (161)Tb-folate and (177)Lu-folate. This was characterized by collapsed tubules and enlarged glomeruli with fibrin deposition in moderately injured kidneys and glomerulosclerosis in severely damaged kidneys. Tb-folate induced dose-dependent radionephropathy over time, but did not result in more severe damage than (177)Lu-folate when applied at the same activity. These data are an indication that Auger/conversion electrons do not exacerbate overall renal damage after application with (161)Tb-folate as compared to (177)Lu-folate, even though they result in an increased dose deposition in the renal tissue. Global toxicity affecting other tissues than kidneys remains to be investigated after (161)Tb-based therapy, however.

Challenges and Opportunities for Testing Students Who Are Deaf or Hard of Hearing: Information for Educators on Creating Test Equity. Test Equity Considerations: Schools

ERIC Educational Resources Information Center

PEPNet-West, 2010

2010-01-01

For most students, test taking is a challenge. For students who are deaf or hard of hearing, classroom quizzes, tests, and exams are even more challenging. Standardized tests--The SAT, ACT, state proficiency tests, No Child Left Behind annual tests, and psychoeducational evaluations--present additional challenges for students who are deaf or hard…

Correlation of in vitro challenge testing with consumer use testing for cosmetic products.

PubMed Central

Brannan, D K; Dille, J C; Kaufman, D J

1987-01-01

An in vitro microbial challenge test has been developed to predict the likelihood of consumer contamination of cosmetic products. The challenge test involved inoculating product at four concentrations (30, 50, 70, and 100%) with microorganisms known to contaminate cosmetics. Elimination of these microorganisms at each concentration was followed over a 28-day period. The test was used to classify products as poorly preserved, marginally preserved, or well preserved. Consumer use testing was then used to determine whether the test predicted the risk of actual consumer contamination. Products classified by the challenge test as poorly preserved returned 46 to 90% contaminated after use. Products classified by the challenge test as well preserved returned with no contamination. Marginally preserved products returned with 0 to 21% of the used units contaminated. As a result, the challenge test described can be accurately used to predict the risk of consumer contamination of cosmetic products. PMID:3662517

[Four infants with upper urinary tract infection due to extended-spectrum bata lactamase (ESBL)-producing Escherichia coli].

PubMed

Hibino, Satoshi; Fukuchi, Kunihiko; Abe, Yoshifusa; Hoshino, Akihiro; Sakurai, Shunsuke; Mikawa, Takeshi; Fuke, Toshiya; Yoshida, Koichiro; Itabashi, Kazuo

2011-09-01

Bacteria producing extended-spectrum beta lactamase (ESBL) are detected mainly in adult urinary specimens, and are believed to cause hospital-acquired infection due to their resistance to many drugs. The incidence of community-acquired infection due to such bacteria is increasing, but few cases of infant upper urinary tract infection (UUTI) have been reported in Japan. We treated four infants with UUTI caused by ESBL-producing Escherichia coli, as determined by genotyping. Using medical records, we retrospectively evaluated the clinical course, antibiotic use and efficacy, antimicrobial susceptibility results, and the presence of underlying disease. One of the four had been previously hospitalized for occult bacteremia. Two developed UUTI after antibiotic treatment, indicating that previous antibiotic use may have been a risk factor in these cases. We could not identify the infection route in all cases. Two of the four had bilateral vesicoureteral reflux (VUR). Renal scintigraphy was done in three. Although an initial dimercaptosuccinic acid (DMSA) defect was detected in all four, only one had renal scarring. E. coli isolates from all four showed PCR signals for blaCTX-M-; one isolate positive for the blaCTX-M3 group and three positive for blaCTX-M14. Antimicrobial susceptibility test results showed all isolates to be resistant to cephalosporins, but discrepancies existed between antimicrobial susceptibility results and actual clinical efficacy. Clinically, cefazolin (CEZ) was effective in two subjects and ceftazidime (CAZ) effective in one. Panipenem/betamipron (PAPM/BP) was effective in one. None of the four developed sepsis or meningitis. Post hospitalization antibiotic prophylaxis showed that none of the four has had UUTI recur. Japan's ESBL-producing bacterial infection incidence is increasing, so medical professionals should watch for such UUTI even in first-case occurrence in infants.

Synthesis of a novel poly-thiolated magnetic nano-platform for heavy metal adsorption. Role of thiol and carboxyl functions

NASA Astrophysics Data System (ADS)

Odio, Oscar F.; Lartundo-Rojas, Luis; Palacios, Elia Guadalupe; Martínez, Ricardo; Reguera, Edilso

2016-11-01

We report a novel strategy for the synthesis of magnetic nano-platforms containing free thiol groups. It first involves the synthesis of a poly(acrylic acid) copolymer containing disulfide bridges between the linear chains through di-ester linkages, followed by the anchoring of this new ligand to magnetite nanoparticles using a ligand exchange reaction. Finally, free sbnd SH groups are obtained by treating the resulting disulfide-functionalized magnetic nano-system with tributyl phosphine as reducing agent. The characterization of the resulting 17 nm nanoparticles (Fe3O4@PAA-HEDred) by FTIR and TGA confirms the attachment of the copolymer through iron carboxylates. XRD, TEM and magnetic measurements indicate an increase in the inorganic core diameter and the occurrence of strong magnetic inter-particle interactions during the exchange reaction, although coercitivity and remanence drop to near zero at room temperature. Afterwards, Fe3O4@PAA-HEDred nanoparticles were tested as sorbent for Pb2+ and Cd2+ cations in aqueous media. XPS measurements were performed in order to unravel the role of both carboxyl and thiol functions in the adsorption process. For the sake of comparison, the same study was performed using bare Fe3O4 nanoparticles and a nanosystem with disulfide groups (Fe3O4@DMSA). The joint analysis of the Pb 4f, Cd 3d, Fe 2p and S 2p high resolution spectra for the nanostructured materials indicates that metal-sulfur interactions are dominant if free sbnd SH groups are present, but if not, the main adsorption route entails metal-carboxyl interactions. Even in presence of unbound thiol moieties, carboxyl groups participate due to favoured steric availability.

Transient Fanconi syndrome in two preterm infants with hydronephrosis and urinary tract infection.

PubMed

Tominaga, Takahiro; Sato, Takeshi; Ichihashi, Yosuke; Amano, Naoko; Kobayashi, Yasuaki; Awazu, Midori

2017-05-01

Type IV renal tubular acidosis is known to occur in obstructive uropathy with urinary tract infection. Fanconi syndrome, however, has not been described in these settings. We report two preterm infants who developed Fanconi syndrome associated with hydronephrosis and urinary tract infection. Patient 1 is a boy with 21 trisomy, bilateral renal hypoplasia and bilateral vesicoureteral reflux delivered at 35 weeks' gestation. At postnatal day 42, he developed Fanconi syndrome after urinary tract infection, which persisted until the surgical correction of vesicoureteral reflux. Patient 2 was delivered at 35 weeks' gestation. At postnatal day 9, he was admitted for severe dehydration. He had phimosis and ultrasonography showed left pelviectasis. Laboratory data were compatible with Fanconi syndrome, which resolved spontaneously after fluid therapy. Subsequently urine culture grew bacteria and treatment for infection and topical corticosteroid for phimosis were performed. DMSA scintigraphy performed later showed left renal scar. Tubular cell stretch, due to vesicoureteral reflux in Patient 1 and phimosis in Patient 2, and urinary tract infection in association with immaturity of tubules are thought to have caused Fanconi syndrome.

Current approaches of the management of mercury poisoning: need of the hour

PubMed Central

2014-01-01

Mercury poisoning cases have been reported in many parts of the world, resulting in many deaths every year. Mercury compounds are classified in different chemical types such as elemental, inorganic and organic forms. Long term exposure to mercury compounds from different sources e.g. water, food, soil and air lead to toxic effects on cardiovascular, pulmonary, urinary, gastrointestinal, neurological systems and skin. Mercury level can be measured in plasma, urine, feces and hair samples. Urinary concentration is a good indicator of poisoning of elemental and inorganic mercury, but organic mercury (e.g. methyl mercury) can be detected easily in feces. Gold nanoparticles (AuNPs) are a rapid, cheap and sensitive method for detection of thymine bound mercuric ions. Silver nanoparticles are used as a sensitive detector of low concentration Hg2+ ions in homogeneous aqueous solutions. Besides supportive therapy, British anti lewisite, dimercaprol (BAL), 2,3-dimercaptosuccinic acid (DMSA. succimer) and dimercaptopropanesulfoxid acid (DMPS) are currently used as chelating agents in mercury poisoning. Natural biologic scavengers such as algae, azolla and other aquatic plants possess the ability to uptake mercury traces from the environment. PMID:24888360

Plain radiography, renography, and 99mTc-DMSA renal scintigraphy before and after extracorporeal shock wave lithotripsy for urolithiasis.

PubMed

Munck, O; Gerquari, I; Møller, J T; Jensen, L I; Thomsen, H S

1992-11-01

Eighteen patients were evaluated before and 5 weeks after the first treatment with extracorporeal shock wave lithotripsy (ESWL) using abdominal plain radiography, 131I-hippuran probe renography, and 99mTc-dimercaptosuccinic acid scintigraphy. In 6 patients no urolithiasis was present on the post ESWL plain radiograph, in 7 the size had decreased, and in 5 the stone mass was unchanged. The renograms were within normal range in the 6 patients who were cured by ESWL, whereas this was the case for only 4 of the 12 who still had renal calculi. In 2 patients pelvic stones had descended into the ureter after ESWL, and the renograms indicated obstruction. Another 3 patients had ureteral stones, whereas in the remaining 7 patients only pelvic stones were found on the plain radiographs. In no patient did the scintigrams reveal scars. It is concluded that abdominal plain radiography of the urinary tract and probe renography are complementary and sufficient in the monitoring of patients with urolithiasis post ESWL.

Three new renal simulators for use in nuclear medicine

NASA Astrophysics Data System (ADS)

Dullius, Marcos; Fonseca, Mateus; Botelho, Marcelo; Cunha, Clêdison; Souza, Divanízia

2014-03-01

Renal scintigraphy is useful to provide both functional and anatomic information of renal flow of cortical functions and evaluation of pathological collecting system. The objective of this study was develop and evaluate the performance of three renal phantoms: Two anthropomorphic static and another dynamic. The static images of the anthropomorphic phantoms were used for comparison with static renal scintigraphy with 99mTc-DMSA in different concentrations. These static phantoms were manufactured in two ways: one was made of acrylic using as mold a human kidney preserved in formaldehyde and the second was built with ABS (acrylonitrile butadiene styrene) in a 3D printer. The dynamic renal phantom was constructed of acrylic to simulate renal dynamics in scintigraphy with 99mTc-DTPA. These phantoms were scanned with static and dynamic protocols and compared with clinical data. Using these phantoms it is possible to acquire similar renal images as in the clinical scintigraphy. Therefore, these new renal phantoms can be very effective for use in the quality control of renal scintigraphy, and image processing systems.

Diagnosis of penicillin allergy revisited: the value of case history, skin testing, specific IgE and prolonged challenge.

PubMed

Hjortlund, J; Mortz, C G; Skov, P S; Bindslev-Jensen, C

2013-08-01

Skin testing in duplicate, correlation between case history of immediate and nonimmediate reactions and challenge outcome and prolonged oral treatment with penicillin in the diagnostic evaluation of allergic reactions to β-lactam antibiotics, mimicking real-life situations, have only been addressed in few studies. A total of 342 patients suspected of having β-lactam allergy were investigated according to the European Network for Drug Allergy (ENDA) guidelines and patients found to be negative in the ENDA program were supplemented with a 7-day oral treatment with penicillin. Skin testing with penicillins was performed in duplicate. Patients with case histories of reactions to other β-lactams were also subsequently challenged with the culprit drug. Nineteen patients were IgE-sensitized to penicillin. Then, intracutaneous tests (ICTs) were performed, in which 35 patients tested positive for allergy, 21 with delayed and 14 with immediate reactions. Only three patients tested positive for the major (PPL) and/or minor (MDM) penicillin determinants, all being positive for penicillin G in ICT. The remaining 291 patients were challenged with penicillin: 10 tested positive in single-dose challenge and 23 tested positive in the 7-day challenge. A total of 17 of 78 patients with a negative penicillin challenge tested positive during challenges with other β-lactams. We found no correlation between case histories of immediate and nonimmediate reactions and reaction time during challenge. The data suggest that case history is often insufficient to discriminate between immediate reactors and nonimmediate reactors. A 7-day challenge with the culprit β-lactam may yield more positive reactions than the accepted one- or 2-day challenge. Interpretation of skin testing should be made with caution. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Testing Scientific Software: A Systematic Literature Review.

PubMed

Kanewala, Upulee; Bieman, James M

2014-10-01

Scientific software plays an important role in critical decision making, for example making weather predictions based on climate models, and computation of evidence for research publications. Recently, scientists have had to retract publications due to errors caused by software faults. Systematic testing can identify such faults in code. This study aims to identify specific challenges, proposed solutions, and unsolved problems faced when testing scientific software. We conducted a systematic literature survey to identify and analyze relevant literature. We identified 62 studies that provided relevant information about testing scientific software. We found that challenges faced when testing scientific software fall into two main categories: (1) testing challenges that occur due to characteristics of scientific software such as oracle problems and (2) testing challenges that occur due to cultural differences between scientists and the software engineering community such as viewing the code and the model that it implements as inseparable entities. In addition, we identified methods to potentially overcome these challenges and their limitations. Finally we describe unsolved challenges and how software engineering researchers and practitioners can help to overcome them. Scientific software presents special challenges for testing. Specifically, cultural differences between scientist developers and software engineers, along with the characteristics of the scientific software make testing more difficult. Existing techniques such as code clone detection can help to improve the testing process. Software engineers should consider special challenges posed by scientific software such as oracle problems when developing testing techniques.

Testing Scientific Software: A Systematic Literature Review

PubMed Central

Kanewala, Upulee; Bieman, James M.

2014-01-01

Context Scientific software plays an important role in critical decision making, for example making weather predictions based on climate models, and computation of evidence for research publications. Recently, scientists have had to retract publications due to errors caused by software faults. Systematic testing can identify such faults in code. Objective This study aims to identify specific challenges, proposed solutions, and unsolved problems faced when testing scientific software. Method We conducted a systematic literature survey to identify and analyze relevant literature. We identified 62 studies that provided relevant information about testing scientific software. Results We found that challenges faced when testing scientific software fall into two main categories: (1) testing challenges that occur due to characteristics of scientific software such as oracle problems and (2) testing challenges that occur due to cultural differences between scientists and the software engineering community such as viewing the code and the model that it implements as inseparable entities. In addition, we identified methods to potentially overcome these challenges and their limitations. Finally we describe unsolved challenges and how software engineering researchers and practitioners can help to overcome them. Conclusions Scientific software presents special challenges for testing. Specifically, cultural differences between scientist developers and software engineers, along with the characteristics of the scientific software make testing more difficult. Existing techniques such as code clone detection can help to improve the testing process. Software engineers should consider special challenges posed by scientific software such as oracle problems when developing testing techniques. PMID:25125798

Transcript profiling of the immunological interactions between Actinobacillus pleuropneumoniae serotype 7 and the host by dual RNA-seq.

PubMed

Li, Ping; Xu, Zhiwen; Sun, Xiangang; Yin, Yue; Fan, Yi; Zhao, Jun; Mao, Xiyu; Huang, Jianbo; Yang, Fan; Zhu, Ling

2017-09-12

The complexity of the pathogenic mechanism underlying the host immune response to Actinobacillus pleuropneumonia (App) makes the use of preventive measures difficult, and a more global view of the host-pathogen interactions and new insights into this process are urgently needed to reveal the pathogenic and immune mechanisms underlying App infection. Here, we infected specific pathogen-free Mus musculus with App serotype 7 by intranasal inoculation to construct an acute hemorrhagic pneumonia infection model and isolated the infected lungs for analysis of the interactions by dual RNA-seq. Four cDNA libraries were constructed, and 2428 differentially expressed genes (DEGs) of the host and 333 DEGs of App were detected. The host DEGs were mainly enriched in inflammatory signaling pathways, such as the TLR, NLR, RLR, BCR and TCR signaling pathways, resulting in large-scale cytokine up-regulation and thereby yielding a cytokine cascade for anti-infection and lung damage. The majority of the up-regulated cytokines are involved in the IL-23/IL-17 cytokine-regulated network, which is crucial for host defense against bacterial infection. The DEGs of App were mainly related to the transport and metabolism of energy and materials. Most of these genes are metabolic genes involved in anaerobic metabolism and important for challenging the host and adapting to the anaerobic stress conditions observed in acute hemorrhagic pneumonia. Some of these genes, such as adhE, dmsA, and aspA, might be potential virulence genes. In addition, the up-regulation of genes associated with peptidoglycan and urease synthesis and the restriction of major virulence genes might be immune evasion strategies of App. The regulation of metabolic genes and major virulence genes indicate that the dominant antigens might differ during the infection process and that vaccines based on these antigens might allow establishment of a precise and targeted immune response during the early phase of infection. Through an analysis of transcriptional data by dual RNA-seq, our study presents a novel global view of the interactions of App with its host and provides a basis for further study.

In Vitro Gluten Challenge Test for Celiac Disease Diagnosis.

PubMed

Khalesi, Maryam; Jafari, Seyed Ali; Kiani, Mohammadali; Picarelli, Antonio; Borghini, Raffaele; Sadeghi, Ramin; Eghtedar, Alireza; Ayatollahi, Hosein; Kianifar, Hamid R

2016-02-01

The in vitro gluten challenge test is an important diagnostic modality in celiac disease (CD), especially in patients who begin treatment with a gluten-free diet before adequate diagnostic workup or in cases with atypical CD. Available literature was reviewed regarding the accuracy of the in vitro gluten challenge test for CD diagnosis. MEDLINE, Scopus, and Google Scholar were searched, and studies that used serology and bowel biopsy as the criterion standard for diagnosis were included in our study. Data on authors, publication year, characteristics of the patient and control groups, patients' diet, duration of the gluten challenge test, histology findings, endomysial antibody (EMA) and anti-tissue transglutaminase (tTG) levels, CD markers, and intercellular cell adhesion molecule-1, and human leukocyte antigens before and after the gluten challenge test were extracted. Overall, 15 studies were included in this meta-analysis. Pooled sensitivity %/specificity % was 84/99 for EMA after the challenge, 52/96 for EMA without the challenge, 95.5/98.3 for anti-tTG after the challenge, and 95.1/98.3 for anti-tTG without the challenge test. Sensitivity/specificity for immunological markers were 89/97 for the percentage of CD25⁺-lamina propria lymphocytes, 96/91 for the percentage of CD3⁺-lamina propria lymphocytes, and 96.1/85.7 for the percentage of intercellular cell adhesion molecule-1-lamina propria lymphocytes. The factors that increased the sensitivity of EMA were longer test duration, and the evaluation of patients on a gluten-containing diet or short-term gluten-free diet. The in vitro gluten challenge test can be a useful part of the diagnostic workup of CD, rather than only a model to evaluate its mechanisms.

Challenging Tasks: What Happens When Challenging Tasks Are Used in Mixed Ability Middle School Mathematics Classrooms?

ERIC Educational Resources Information Center

Perkins, Karen

2016-01-01

The topics of decimals and polygons were taught to two classes by using challenging tasks, rather than the more conventional textbook approach. Students were given a pre-test and a post-test. A comparison between the two classes on the pre- and post-test was made. Prior to teaching through challenging tasks, students were surveyed about their…

NICE guidelines for imaging studies in children with UTI adequate only in boys under the age of 6 months.

PubMed

Ristola, Marko Tapani; Hurme, Timo

2013-03-01

The purpose of this study was to evaluate the applicability of the National Institute for Health and Clinical Excellence (NICE) guidelines for imaging studies in children under the age of three with first urinary tract infection (UTI). In our cohort of 112 patients, we gathered data regarding the occurrence of indications for ultrasonography (US) and voiding cystourethrography (VCUG) according to the NICE guidelines, dimercaptosuccinic acid (DMSA) scintigraphy examinations, UTI recurrence, antimicrobial prophylaxis (AMP), anti-reflux procedures, and other urological procedures. If the NICE guidelines had been applied, 13 of the 25 patients (52 %) with vesicoureteral reflux (VUR), including 6 of the 12 patients (50 %) with dilating VUR and 3 of the 4 patients who underwent endoscopic anti-reflux treatment, would have been missed, and a negative VCUG would have been avoided in 25 of the 42 patients (60 %) with no VUR. None of the missed diagnoses occurred in the younger boys' group. Based on these preliminary analyses, we feel that the NICE guidelines for imaging studies in children under 3 years old with UTI may be applicable to clinical use only in boys under 6 months of age. For other patients the guidelines were unsuccessful.

In vitro study on apoptotic cell death by effective magnetic hyperthermia with chitosan-coated MnFe2O4

NASA Astrophysics Data System (ADS)

Oh, Yunok; Lee, Nohyun; Kang, Hyun Wook; Oh, Junghwan

2016-03-01

Magnetic nanoparticles (MNPs) have been widely investigated as a hyperthermic agent for cancer treatment. In this study, thermally responsive Chitosan-coated MnFe2O4 (Chitosan-MnFe2O4) nanoparticles were developed to conduct localized magnetic hyperthermia for cancer treatment. Hydrophobic MnFe2O4 nanoparticles were synthesized via thermal decomposition and modified with 2,3-dimercaptosuccinic acid (DMSA) for further conjugation of chitosan. Chitosan-MnFe2O4 nanoparticles exhibited high magnetization and excellent biocompatibility along with low cell cytotoxicity. During magnetic hyperthermia treatment (MHT) with Chitosan-MnFe2O4 on MDA-MB 231 cancer cells, the targeted therapeutic temperature was achieved by directly controlling the strength of the external AC magnetic fields. In vitro Chitosan-MnFe2O4-assisted MHT at 42 °C led to drastic and irreversible changes in cell morphology and eventual cellular death in association with the induction of apoptosis through heat dissipation from the excited magnetic nanoparticles. Therefore, the Chitosan-MnFe2O4 nanoparticles with high biocompatibility and thermal capability can be an effective nano-mediated agent for MHT on cancer.

Managing Challenges in a Multi Contractor Project

NASA Technical Reports Server (NTRS)

King, Ron

2011-01-01

The presentation provides a project description, describes the integrated product team, and review project challenges. The challenges include programmatic, technical, basic drop tests, heavy drop tests, C-17 envelope expansion, and Ares I-X.

A retrospective comparison of false negative skin test rates in penicillin allergy, using pencilloyl-poly-lysine and minor determinants or Penicillin G, followed by open challenge.

PubMed

Rosenfield, Lana; Kalicinsky, Chrystyna; Warrington, Richard

2015-01-01

A history of penicillin allergy in patients is common, but only 10-15 % are truly allergic. While the gold standard for diagnosing penicillin allergy is challenge, it is not recommended that this be done without first carrying out diagnostic skin testing. This is carried out with the major determinant benzylpenicilloyl (PPL) and the minor determinant mixture (MDM), consisting of penilloate, penicilloate and Penicillin G. However, since availability of the MDM is limited, Penicillin G alone has been used. A retrospective chart review was carried out on patients tested for penicillin allergy in the Clinical Immunology and Allergy Clinic at the Health Sciences Centre, Winnipeg, Canada between 2005 and 2013. A total of 521 patients charts were reviewed, of whom 240 had skin testing, ImmunoCap(®) for IgE to Penicillin G and V and had oral challenges with penicillin, amoxicillin or cloxacillin. 17/240 (7.5 %) were skin test positive, 8 to PPL, 4 to MDM and 5 to Penicillin G. One was also positive on ImmunoCap(®) testing. Three patients had negative skin tests but weakly positive ImmunoCap(®). 222 patients with negative skin tests and serological tests were challenged. Of these, 12 patients reacted to challenge. Three of the challenges were equivocal. Of the nine patients with definite positive challenges, three were tested with Penicillin G and six with MDM. Therefore the false negative rates for testing were 2.3 % with PPL and Penicillin G and 6.97 % for PPL and MDM. The difference was not significant (p = 0.0856). In this group of patients with a history of penicillin allergy tested with the major determinant of benzyl penicillin and either MDM or Penicillin G, there was no difference in the rate of false negative testing, based on oral penicillin challenges. Therefore, Penicillin G can be safely used as an alternative to MDM in diagnosing penicillin allergy.

Prediction of challenge test results by flour-specific IgE and skin prick test in symptomatic bakers.

PubMed

van Kampen, V; Rabstein, S; Sander, I; Merget, R; Brüning, T; Broding, H C; Keller, C; Müsken, H; Overlack, A; Schultze-Werninghaus, G; Walusiak, J; Raulf-Heimsoth, M

2008-07-01

Wheat and rye flours are among the most important allergens causing occupational asthma. Usually, the diagnosis of baker's asthma is based on inhalation challenge tests with flours. To evaluate the relevance of flour-specific serum immunoglobulin E (IgE) and skin prick test (SPT) in the diagnosis of baker's asthma and to define flour-specific IgE concentrations and wheal sizes that allow a prediction of the outcome of challenge testing. Bronchial and nasal challenge tests with wheat (rye) flour were performed in 71 (95) symptomatic bakers. Determinations of flour-specific IgE as well as SPTs were performed in all subjects. Analyses included the calculation of sensitivity, specificity, positive (PPV) and negative predictive values (NPV) at different IgE concentrations and different wheal sizes, and receiver-operating characteristics (ROC) plots with the challenge result as gold standard. Thirty-seven bakers were positive in the challenge with wheat flour, while 63 were positive with rye flour. Depending on the flour-specific IgE concentrations (wheal size), PPV was 74-100% (74-100%) for wheat and 82-100% (91-100%) for rye flour, respectively. The minimal cut-off values with a PPV of 100% were 2.32 kU/l (5.0 mm) for wheat flour and 9.64 kU/l (4.5 mm) for rye flour. The shapes of the ROC plots were similar for wheat and rye flour. High concentrations of flour-specific IgE and clear SPT results in symptomatic bakers are good predictors for a positive challenge test. Challenge tests with flours may be avoided in strongly sensitized bakers.

Skin testing and oral penicillin challenge in patients with a history of remote penicillin allergy.

PubMed

Goldberg, Arnon; Confino-Cohen, Ronit

2008-01-01

Penicillin administration is usually contraindicated in penicillin-allergic patients with positive skin test results. To examine whether penicillin oral challenge for patients with a history of remote non-life-threatening allergic reaction to penicillin can be well tolerated irrespective of skin test results. In a prospective open-label trial, 8,702 individuals were screened between November 1998 and January 2000. Of 687 patients with a non-life-threatening allergic reaction to penicillin, occurring longer than 3 years earlier, 169 were enrolled. Regardless of the response to penicillin skin testing, patients received the usual 1-day dosage of penicillin and amoxicillin, on 2 separate occasions. Two to 6 years later, a follow-up was conducted to assess the outcomes of further penicillin administration. A total of 272 combined skin tests and oral challenges were performed on 169 patients. Among 137 challenges with a positive skin test result and 135 patients with a negative skin test result, 9 (6.6%) and 5 (3.7%) (P = .29), respectively, developed a mild rash to oral challenge. At follow-up, 2 to 6 years afterward, 3 of 55 patients (5.5%) who were given a full treatment course of penicillin developed a mild skin eruption. Positive penicillin skin test results for patients with a remote history of non-life-threatening allergic reaction to penicillin were not associated with a greater prevalence of adverse reactions to oral challenge with penicillin than negative results. Because skin testing is considered the gold standard and the safest method for predicting tolerance to penicillin administration, oral penicillin challenge may be used as a diagnostic method only in these specific patients when skin testing is not feasible.

Asthma control in patients on fixed dose combination evaluated with mannitol challenge test.

PubMed

Romberg, Kerstin A M; Berggren, Anna-Carin; Bjermer, Leif

2014-02-01

Asthma is often difficult to control and it is likely that not all patients are optimally treated. This study aimed to explore asthma control in adults receiving fixed dose combination (FDC) therapy. Control of asthma was assessed using the mannitol challenge test as a monitoring tool to see if this would give additional information compared to the asthma control test (ACT). The study was an open-label, prospective study on 98 adults prescribed with FDC therapies for at least three months. 74 patients considered that their asthma was well controlled. However, 60 patients had a positive mannitol challenge test (PD15 < 635 mg), and when those with a positive response to the short-acting β2-agonist (≥15%) after the mannitol challenge test were included, this increased to 64 patients (65%). Exploratory analysis determined that the spirometry parameters; FEV1/FVC and FEV1% of predicted, were statistically significant predictors of a positive mannitol challenge test. Co-morbid conditions such as concomitant upper airway involvement or eczema did not predict mannitol reactivity. Although most patients rated their asthma as well controlled, many provided a positive mannitol challenge test, suggesting the presence of underlying inflammation, despite treatment with fixed dose combination therapy. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Rapid diagnostic tests for malaria

PubMed Central

Daily, Jennifer; Hotte, Nora; Dolkart, Caitlin; Cunningham, Jane; Yadav, Prashant

2015-01-01

Abstract Maintaining quality, competitiveness and innovation in global health technology is a constant challenge for manufacturers, while affordability, access and equity are challenges for governments and international agencies. In this paper we discuss these issues with reference to rapid diagnostic tests for malaria. Strategies to control and eliminate malaria depend on early and accurate diagnosis. Rapid diagnostic tests for malaria require little training and equipment and can be performed by non-specialists in remote settings. Use of these tests has expanded significantly over the last few years, following recommendations to test all suspected malaria cases before treatment and the implementation of an evaluation programme to assess the performance of the malaria rapid diagnostic tests. Despite these gains, challenges exist that, if not addressed, could jeopardize the progress made to date. We discuss recent developments in rapid diagnostic tests for malaria, highlight some of the challenges and provide suggestions to address them. PMID:26668438

Challenge of COPD: Getting Tested

MedlinePlus

... please turn JavaScript on. Feature: The Challenge of COPD Getting Tested Past Issues / Fall 2014 Table of Contents Getting Tested Everyone at risk for COPD who has cough, sputum production, or shortness of ...

Transposon Mutagenesis Identified Chromosomal and Plasmid Genes Essential for Adaptation of the Marine Bacterium Dinoroseobacter shibae to Anaerobic Conditions

PubMed Central

Ebert, Matthias; Laaß, Sebastian; Burghartz, Melanie; Petersen, Jörn; Koßmehl, Sebastian; Wöhlbrand, Lars; Rabus, Ralf; Wittmann, Christoph; Jahn, Dieter

2013-01-01

Anaerobic growth and survival are integral parts of the life cycle of many marine bacteria. To identify genes essential for the anoxic life of Dinoroseobacter shibae, a transposon library was screened for strains impaired in anaerobic denitrifying growth. Transposon insertions in 35 chromosomal and 18 plasmid genes were detected. The essential contribution of plasmid genes to anaerobic growth was confirmed with plasmid-cured D. shibae strains. A combined transcriptome and proteome approach identified oxygen tension-regulated genes. Transposon insertion sites of a total of 1,527 mutants without an anaerobic growth phenotype were determined to identify anaerobically induced but not essential genes. A surprisingly small overlap of only three genes (napA, phaA, and the Na+/Pi antiporter gene Dshi_0543) between anaerobically essential and induced genes was found. Interestingly, transposon mutations in genes involved in dissimilatory and assimilatory nitrate reduction (napA, nasA) and corresponding cofactor biosynthesis (genomic moaB, moeB, and dsbC and plasmid-carried dsbD and ccmH) were found to cause anaerobic growth defects. In contrast, mutation of anaerobically induced genes encoding proteins required for the later denitrification steps (nirS, nirJ, nosD), dimethyl sulfoxide reduction (dmsA1), and fermentation (pdhB1, arcA, aceE, pta, acs) did not result in decreased anaerobic growth under the conditions tested. Additional essential components (ferredoxin, cccA) of the anaerobic electron transfer chain and central metabolism (pdhB) were identified. Another surprise was the importance of sodium gradient-dependent membrane processes and genomic rearrangements via viruses, transposons, and insertion sequence elements for anaerobic growth. These processes and the observed contributions of cell envelope restructuring (lysM, mipA, fadK), C4-dicarboxylate transport (dctM1, dctM3), and protease functions to anaerobic growth require further investigation to unravel the novel underlying adaptation strategies. PMID:23974024

Skin testing only with penicillin G in children with a history of penicillin allergy.

PubMed

Picard, Matthieu; Paradis, Louis; Bégin, Philippe; Paradis, Jean; Des Roches, Anne

2014-07-01

The absence of commercially available penicilloyl-polylysine (PPL) for most of the last decade severely hampered the practice of penicillin allergy evaluation because skin testing without PPL is reported to have a poor negative predictive value (NPV). To determine the safety and NPV of skin testing without PPL using only penicillin G followed by a 3-dose graded challenge to the incriminated penicillin in children with a history of penicillin allergy. Patients evaluated for a history of penicillin allergy at the CHU Sainte-Justine Allergy Clinic between December 2006 and December 2009 were skin tested only with penicillin G and underwent a 3-dose graded challenge to the culprit penicillin if the skin test result was negative. Among 563 patients skin tested to penicillin G, 185 (33%) had a positive skin test result. These patients had a shorter interval between the initial reaction and skin testing compared with patients with a negative skin test result (P = .03). A total of 375 of 378 patients (99%) with a negative skin test result were challenged and 18 (4.8%) reacted, translating into a NPV of 95.2% (95% confidence interval [CI], 92.5%-97.1%). Three of 17 patients with a history of anaphylaxis and a negative skin test result reacted to challenge (NPV, 82.4%; 95% CI, 59.0-93.8%). All challenge reactions were mild and resolved promptly with treatment. Among children with a history of penicillin allergy, skin testing only with penicillin G followed by a 3-dose graded challenge to the incriminated penicillin is safe and yields a good NPV. This approach could be useful when PPL is unavailable. Copyright © 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

WLCG scale testing during CMS data challenges

NASA Astrophysics Data System (ADS)

Gutsche, O.; Hajdu, C.

2008-07-01

The CMS computing model to process and analyze LHC collision data follows a data-location driven approach and is using the WLCG infrastructure to provide access to GRID resources. As a preparation for data taking, CMS tests its computing model during dedicated data challenges. An important part of the challenges is the test of the user analysis which poses a special challenge for the infrastructure with its random distributed access patterns. The CMS Remote Analysis Builder (CRAB) handles all interactions with the WLCG infrastructure transparently for the user. During the 2006 challenge, CMS set its goal to test the infrastructure at a scale of 50,000 user jobs per day using CRAB. Both direct submissions by individual users and automated submissions by robots were used to achieve this goal. A report will be given about the outcome of the user analysis part of the challenge using both the EGEE and OSG parts of the WLCG. In particular, the difference in submission between both GRID middlewares (resource broker vs. direct submission) will be discussed. In the end, an outlook for the 2007 data challenge is given.

A comparison of skin prick tests, intradermal skin tests, and specific IgE in the diagnosis of mouse allergy.

PubMed

Sharma, Hemant P; Wood, Robert A; Bravo, Andrea R; Matsui, Elizabeth C

2008-04-01

Mouse sensitization is assessed by using skin testing and serum levels of mouse allergen-specific IgE (m-IgE). However, it is unknown whether a positive skin test response or m-IgE result accurately identifies those with clinically relevant mouse sensitization. We sought to compare skin testing and m-IgE measurement in the diagnosis of mouse allergy. Sixty-nine mouse laboratory workers underwent skin prick tests (SPTs), intradermal tests (IDTs), and serum IgE measurements to mouse allergen, followed by nasal challenge to increasing concentrations of mouse allergen. Challenge response was assessed by nasal symptom score. Thirty-eight women and 31 men with a mean age of 30 years were studied. Forty-nine workers reported mouse-related symptoms, of whom 10 had positive m-IgE results and 12 had positive SPT responses. Fifteen had negative SPT responses but positive IDT responses. Positive nasal challenges were observed in 70% of workers with positive m-IgE results, 83% of workers with positive SPT responses, 33% of workers with negative SPT responses/positive IDT responses, and 0% of workers with negative IDT responses. SPTs performed best, having the highest positive and negative predictive values. Among participants with a positive challenge result, those with a positive SPT response or m-IgE result had a significantly lower challenge threshold than those with a positive IDT response (P = .01). Workers with a positive challenge result were more likely to have an increase in nasal eosinophilia after the challenge compared with those with a negative challenge result (P = .03). SPTs perform best in discriminating patients with and without mouse allergy. Mouse-specific IgE and IDTs appear to be less useful than SPTs in the diagnosis of mouse allergy.

42 CFR 410.18 - Diabetes screening tests.

Code of Federal Regulations, 2010 CFR

2010-10-01

... this subpart are met: (1) Fasting blood glucose test. (2) Post-glucose challenges including, but not...-pregnant adults, a 2-hour post glucose challenge test alone. (3) Other tests as determined by the Secretary... 42 Public Health 2 2010-10-01 2010-10-01 false Diabetes screening tests. 410.18 Section 410.18...

42 CFR 410.18 - Diabetes screening tests.

Code of Federal Regulations, 2014 CFR

2014-10-01

... this subpart are met: (1) Fasting blood glucose test. (2) Post-glucose challenges including, but not...-pregnant adults, a 2-hour post glucose challenge test alone. (3) Other tests as determined by the Secretary... 42 Public Health 2 2014-10-01 2014-10-01 false Diabetes screening tests. 410.18 Section 410.18...

42 CFR 410.18 - Diabetes screening tests.

Code of Federal Regulations, 2012 CFR

2012-10-01

... this subpart are met: (1) Fasting blood glucose test. (2) Post-glucose challenges including, but not...-pregnant adults, a 2-hour post glucose challenge test alone. (3) Other tests as determined by the Secretary... 42 Public Health 2 2012-10-01 2012-10-01 false Diabetes screening tests. 410.18 Section 410.18...

42 CFR 410.18 - Diabetes screening tests.

Code of Federal Regulations, 2013 CFR

2013-10-01

... this subpart are met: (1) Fasting blood glucose test. (2) Post-glucose challenges including, but not...-pregnant adults, a 2-hour post glucose challenge test alone. (3) Other tests as determined by the Secretary... 42 Public Health 2 2013-10-01 2013-10-01 false Diabetes screening tests. 410.18 Section 410.18...

42 CFR 410.18 - Diabetes screening tests.

Code of Federal Regulations, 2011 CFR

2011-10-01

... this subpart are met: (1) Fasting blood glucose test. (2) Post-glucose challenges including, but not...-pregnant adults, a 2-hour post glucose challenge test alone. (3) Other tests as determined by the Secretary... 42 Public Health 2 2011-10-01 2011-10-01 false Diabetes screening tests. 410.18 Section 410.18...

Cost-effectiveness of various methods of diagnosing hypersensitivity to Alternaria.

PubMed

Escudero, A I; Sánchez-Guerrero, I M; Mora, A M; Soriano, V; López, J D; García, F J; Negro, J M; Hernández, J; Pagán, J A

1993-01-01

This study was undertaken for two reasons: 1) It is more difficult to diagnose hypersensitivity to molds than to other allergens, so an evaluation of diagnostic tests was needed. 2) Alternaria is the principal cause of mold sensitization in our area. Sixty-six patients (20 +/- 4 years) were selected and divided into two groups. Group A was made up of patients with rhinitis and/or asthma due to Alternaria sensitization. Group B consisted of patients sensitized to other allergens and patients with nonrespiratory allergic disorders. Skin tests (prick and intradermal), challenge tests (conjunctival, nasal, and bronchial), and specific IgE determination were performed for all patients. A biologically standardized extract of Alternaria tenuis (Alergia e Inmunología Abelló, S. A., Madrid, Spain) obtained from a single batch was used for all tests. Our diagnostic criterion was a clinical history of rhinitis or asthma that coincided with the results of nasal/bronchial challenge. The diagnostic value of the other tests was compared to this criterion. In the group of rhinitic patients, skin tests and conjunctival challenge were more sensitive than specific IgE determination. In asthmatic patients, the most sensitive techniques were nasal and conjunctival challenges, followed by prick and intradermal skin tests, and, lastly, serum specific IgE determination. When rhinitis and asthma were considered jointly, the most sensitive test was conjunctival challenge, followed by skin-prick and intradermal tests. All tests had the same specificity, regardless of disorder. Nasal challenge was positive in all patients. Skin tests are easy to perform, cheap, non-traumatic for the patient, and sufficiently specific and sensitive for the diagnosis of Alternaria hypersensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Drug Testing Programs Face Snags and Legal Challenges.

ERIC Educational Resources Information Center

Cowart, Virginia S.

1988-01-01

A description of the problems that occurred with attempts to conduct drug tests at the 1987 Pan American games leads to a discussion of the legal challenges to drug testing and the need to establish a clear, effective, and fair policy for drug tests of athletes. (CB)

Oral challenge test with sodium metabisulfite in steroid-dependent asthmatic patients.

PubMed

Prieto, L; Juyol, M; Paricio, A; Martínez, M A; Palop, J; Castro, J

1988-01-01

Oral challenge tests were carried out with sodium metabisulfite solution doses of 0.5, 1, 10, 25, 50 mg and encapsulated doses of 100 and 200 mg, as well as with lactose-placebo, on 44 non-atopic patients with steroid-dependent bronchial asthma, without clinical evidence of intolerance to these agents. Only those patients with an acceptable and not very labile pulmonary function were tested. A single-blind challenge protocol was performed in 22 patients (sodium metabisulfite solutions at pH 2.2 to 2.6) and the positive responses were confirmed by double-blind challenge. The other 22 were tested directly in a double-blind manner (pH4). Initially, 6/44 presented a positive reaction. However, a careful analysis and the confirmation by double-blind challenge of the positive responses obtained with the single-blind test, allowed us to identify 4 false positive responses. Thus, the true prevalence of sulfite sensitivity in our population is 4.5%. A patient with intolerance to sulfite agents also suffered aspirin-induced asthma. The labile tendency of the pulmonary function of the asthmatic patients may have contributed to some false positive reactions and probably explain the very high prevalence found in some studies. It does not appear that the variations of pH decisively influence the result of the challenge test.

Swimming endurance of bull trout, lake trout, arctic char, and rainbow trout following challenge with Renibacterium salmoninarum

USGS Publications Warehouse

Jones, D.T.; Moffitt, C.M.

2004-01-01

We tested the swimming endurance of juvenile bull trout Salvelinus confluentus, lake trout S. namaycush, Arctic char S. alpinus, and rainbow trout Oncorhynchus mykiss at 9??C and 15??C to determine whether sublethal infection from a moderate challenge of Renibacterium salmoninarum administered months before testing affected the length of time fish could maintain a swimming speed of 5-6 body lengths per second in an experimental flume. Rainbow trout and Arctic char swam longer in trials than did bull trout or lake trout, regardless of challenge treatment. When we tested fish 14-23 weeks postchallenge, we found no measurable effect of R. salmoninarum on the swimming endurance of the study species except for bull trout, which showed a mixed response. We conducted additional trials with bull trout 5-8 weeks postchallenge to determine whether increasing the challenge dose would affect swimming endurance and hematocrit. In those tests, bull trout with clinical signs of disease and those exposed to the highest challenge doses had significantly reduced swimming endurance compared with unchallenged control fish. Fish hematocrit levels measured at the end of all swimming endurance tests varied among species and between test temperatures, and patterns were not always consistent between challenged and control fish.

Dissociation between history and challenge in patients with physical urticaria.

PubMed

Komarow, Hirsh D; Arceo, Sarah; Young, Michael; Nelson, Celeste; Metcalfe, Dean D

2014-01-01

Physical urticaria is a subtype of chronic urticaria induced by a physical stimulus. To evaluate the consistency between a history of physical urticaria and results of challenge testing. Seventy-six subjects, ages 3 to 77 years old, were referred with the diagnosis of a physical urticaria and were evaluated by using challenge testing directed toward the presenting diagnosis, yet included other stimuli based on history. The majority of subjects were tested to 3 or more stimuli, thus 294 provocation tests were performed. Fifty-seven subjects were surveyed for the status of their physical urticaria at least 1 year after initial evaluation. Of the 76 subjects with a positive history of a physical urticaria, 38% (n = 29) were challenge negative to the presenting diagnosis. Eight subjects within the challenge negative group reacted positively to additional testing, thus 28% (n = 21) remained negative to all challenge testing, which allowed discontinuation of medications and avoidance behavior. A negative challenge result was less likely with subjects who presented with cold-induced urticaria (25%), delayed pressure urticaria (25%), and dermatographism (29%), yet more common with cholinergic (65%) and solar urticaria (67%). A 1-year follow-up survey of 57 subjects was consistent with initial results. Nineteen of this subgroup were rechallenged for the presenting diagnosis, and the outcome was unchanged in 17 subjects and, in 2 subjects the urticaria had resolved. The diagnosis by history of a physical urticaria should be verified by testing whenever possible and particularly if the condition is judged as severe and thus requires both significant life-style changes and pharmacologic intervention. Published by Elsevier Inc.

Using a gluten oral food challenge protocol to improve diagnosis of wheat-dependent exercise-induced anaphylaxis.

PubMed

Brockow, Knut; Kneissl, Daniel; Valentini, Luzia; Zelger, Otto; Grosber, Martine; Kugler, Claudia; Werich, Martina; Darsow, Ulf; Matsuo, Hiroaki; Morita, Eishin; Ring, Johannes

2015-04-01

Oral wheat plus cofactors challenge tests in patients with wheat-dependent exercise-induced anaphylaxis (WDEIA) produce unreliable results. We sought to confirm WDEIA diagnosis by using oral gluten flour plus cofactors challenge, to determine the amount of gluten required to elicit symptoms, and to correlate these results with plasma gliadin levels, gastrointestinal permeability, and allergologic parameters. Sixteen of 34 patients with a history of WDEIA and ω5-gliadin IgE underwent prospective oral challenge tests with gluten with or without cofactors until objective symptoms developed. Gluten reaction threshold levels, plasma gliadin concentrations, gastrointestinal permeability, sensitivities and specificities for skin prick tests, and specific IgE levels were ascertained in patients and 38 control subjects. In 16 of 16 patients (8 female and 8 male patients; age, 23-76 years), WDEIA was confirmed by challenges with gluten alone (n = 4) or gluten plus cofactors (n = 12), including 4 patients with previous negative wheat challenge results. Higher gluten doses or acetylsalicylic acid (ASA) plus alcohol instead of physical exercise were cofactors in 2 retested patients. The cofactors ASA plus alcohol and exercise increased plasma gliadin levels (P < .03). Positive challenge results developed after a variable period of time at peak or when the plateau plasma gliadin level was attained. Positive plasma gliadin threshold levels differed by greater than 100-fold and ranged from 15 to 2111 pg/mL (median, 628 pg/mL). The clinical history, IgE gliadin level, and baseline gastrointestinal level were not predictive of the outcomes of the challenge tests. The challenge-confirmed sensitivity and specificity of gluten skin prick tests was 100% and 96%, respectively. Oral challenge with gluten alone or along with ASA and alcohol is a sensitive and specific test for the diagnosis of WDEIA. Exercise is not an essential trigger for the onset of symptoms in patients with WDEIA. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Critical evaluation of the EU-technical guidance on shelf-life studies for L. monocytogenes on RTE-foods: a case study for smoked salmon.

PubMed

Vermeulen, A; Devlieghere, F; De Loy-Hendrickx, A; Uyttendaele, M

2011-01-31

In November 2008, a technical guidance document on the challenge test protocol was published by the EU CRL (Community of Reference Laboratory) for L. monocytogenes. This document describes the practical aspects on the execution of a challenge test in order to comply to the EU Commission regulation N° 2073/2005 on microbiological criteria for foodstuff. In this guideline two approaches are specified. On the one hand challenge tests, based on actual data measurements at the beginning and end of the shelf-life of products stored under reasonably foreseen T-profile, are described. On the other hand, growth potential is calculated by predictive models using a validated maximum specific growth rate. The present study evaluates the two above mentioned approaches on cold smoked salmon, a typical risk product for L. monocytogenes. The focus is on: (i) the relative importance of intrabatch versus interbatch variability, (ii) the concept of a simple challenge test based on actual data at start and end of shelf life versus a modelling approach and (iii) the interpretation of challenge tests. Next to this, available tertiary models were used to estimate the growth potential of these products based on their initial physicochemical characteristics. From the results it could be concluded that in some batches considerable intrabatch variability was obtained. In general, however, the interbatch variability was significantly higher than intrabatch variability. Concerning the two above mentioned methods for challenge tests, it can be stated that the first approach (simple challenge test) can be set up rather rapidly and is cost-effective for SMEs (small and medium enterprises) but provides only a single isolated outcome. This implies that challenge tests should be redone if changes occur in composition or production process. The second (modelling) approach, using extended challenge tests to establish growth parameters needs larger set ups and more complicated data analysis, which makes them more expensive. Using available tertiary models has the major advantage that the most important intrinsic and extrinsic factors can be included for the prediction of the growth parameter. It was clear that product specific models, taking into account the interaction effects with background flora, performed the best. Regarding the challenge tests, it can be concluded that the best approach to choose will depend on the particular context as in the end both approaches will lead to the same conclusion. Copyright © 2010 Elsevier B.V. All rights reserved.

KSC-2009-6487

NASA Image and Video Library

2009-11-19

CAPE CANAVERAL, Fla. – At the Astronaut Hall of Fame near NASA’s Kennedy Space Center in Florida, Patrick Simpkins, director of Engineering at Kennedy, tries out a pair of space gloves for their dexterity and flexibility in a glove box at the 2009 Astronaut Glove Challenge, part of NASA’s Centennial Challenges Program. Looking over his shoulder is Kennedy Director Bob Cabana. The nationwide competition focused on developing improved pressure suit gloves for astronauts to use while working in space. During the challenge, the gloves were submitted to burst tests, joint force tests and tests to measure their dexterity and strength during operation in a glove box which simulates the vacuum of space. Centennial Challenges is NASA’s program of technology prizes for the citizen-inventor. The winning prize for the Glove Challenge is $250,000 provided by the Centennial Challenges Program. Photo credit: NASA/Kim Shiflett

KSC-2009-6488

NASA Image and Video Library

2009-11-19

CAPE CANAVERAL, Fla. – At the Astronaut Hall of Fame near NASA’s Kennedy Space Center in Florida, participants in the 2009 Astronaut Glove Challenge, part of NASA’s Centennial Challenges Program, pose for a group portrait. In the center of the front row are the winners, Ted Southern of Brooklyn, N.Y., at left, and Peter Homer of Southwest Harbor, Maine. The nationwide competition focused on developing improved pressure suit gloves for astronauts to use while working in space. During the challenge, the gloves were submitted to burst tests, joint force tests and tests to measure their dexterity and strength during operation in a glove box which simulates the vacuum of space. Centennial Challenges is NASA’s program of technology prizes for the citizen-inventor. The winning prize for the Glove Challenge is $250,000 provided by the Centennial Challenges Program. Photo credit: NASA/Kim Shiflett

Some considerations on the safety evaluation of nonviral microbial pesticides

PubMed Central

Shadduck, J. A.

1983-01-01

The tactics and rationale of maximum challenge safety tests for nonviral microbial pesticides have been reviewed. Maximum challenge tests and a tier approach to data collection for regulatory purposes offer the best opportunities to detect the acute effects of entomopathogenic organisms in mammals. Premature condemnation of promising organisms that are based on incomplete results of maximum challenge tests must be avoided. Further investigations should be conducted on the role of mammalian immune response in resistance to entomopathogenic organisms and on the value of medium- or long-term exposure tests. PMID:6601535

Developments in Test Facility and Data Networking for the Altitude Test Stand at the John C. Stennis Space Center: A General Overview

NASA Technical Reports Server (NTRS)

Hebert, Phillip W.

2008-01-01

NASA/SSC's Mission in Rocket Propulsion Testing Is to Acquire Test Performance Data for Verification, Validation and Qualification of Propulsion Systems Hardware: Accurate, Reliable, Comprehensive, and Timely. Data Acquisition in a Rocket Propulsion Test Environment Is Challenging: a) Severe Temporal Transient Dynamic Environments; b) Large Thermal Gradients; c) Vacuum to high pressure regimes. A-3 Test Stand Development is equally challenging with respect to accommodating vacuum environment, operation of a CSG system, and a large quantity of data system and control channels to determine proper engine performance as well as Test Stand operation. SSC is currently in the process of providing modernized DAS, Control Systems, Video, and network systems for the A-3 Test Stand to overcome these challenges.

Predictors of renal scar in children with urinary infection and vesicoureteral reflux.

PubMed

Soylu, Alper; Demir, Belde Kasap; Türkmen, Mehmet; Bekem, Ozlem; Saygi, Murat; Cakmakçi, Handan; Kavukçu, Salih

2008-12-01

We evaluated the predictors of renal scar in children with urinary tract infections (UTIs) having primary vesicoureteral reflux (VUR). Data of patients who were examined by dimercaptosuccinic acid (DMSA) scintigraphy between 1995 and 2005 were evaluated retrospectively. Gender, age, reflux grade, presence/development of scarring, breakthrough UTIs, and resolution of reflux, were recorded. The relation of gender, age and VUR grade to preformed scarring and the relation of gender, age, VUR grade, presence of preformed scarring, number of breakthrough UTIs and reflux resolution to new scarring were assessed. There were 138 patients [male/female (M/F) 53/85]. Multivariate analysis showed that male gender [odds ratio (OR) 2.5], age > or = 27 months in girls (OR 4.2) and grades IV-V reflux (OR 12.4) were independent indicators of renal scarring. On the other hand, only the presence of previous renal scarring was found to be an independent indicator for the development of new renal scar (OR 13.4). In conclusion, while the most predictive variables for the presence of renal scarring among children presenting with a UTI were male gender, age > or = 27 months in girls, and grades IV-V reflux, the best predictor of new scar formation was presence of previous renal scarring.

High incidence of vesicoureteric reflux in asymptomatic siblings of children with known reflux

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

Treves, S.T.; Van den Abbeele, A.D.; Davis, R.T.

1985-05-01

A significant occurrence of vesicoureteric reflux in siblings of children with reflux has been previously suggested. The purpose of this study was to evaluate the incidence of vesicoureteric reflux in asymptomatic siblings of children with vesicoureteric reflux using radionuclide voiding cystography (RNC). A random group of 52 siblings was studied. Their ages were from 2 mos. to 13 yrs. (mean 4 yrs.). Seventy-one percent were female and 29% male, RNC was performed with the patients supine, and Tc-99m pertechnetate (2mCi/1) was infused into the bladder by catheter. A computerized gamma camera recorded the filling and voiding phase of the studymore » at 1 frame/5 sec. Reflux was detected in 40% of the patients. It was bilateral in 17% and unilateral in 23% of the patients. Reflux was identified to the renal pelves in half of the patients. In two of these patients Tc-99m DMSA scans were obtained which revealed significant renal scarring. This study demonstrates the high incidence of reflux of various degrees in these asymptomatic siblings on high risk of developing significant renal disease. Identification and proper treatment of asymptomatic children with vesicoureteric reflux may help prevent the development of renal damage.« less

Automated Source-Code-Based Testing of Object-Oriented Software

NASA Astrophysics Data System (ADS)

Gerlich, Ralf; Gerlich, Rainer; Dietrich, Carsten

2014-08-01

With the advent of languages such as C++ and Java in mission- and safety-critical space on-board software, new challenges for testing and specifically automated testing arise. In this paper we discuss some of these challenges, consequences and solutions based on an experiment in automated source- code-based testing for C++.

Bronchial hyperresponsiveness testing in athletes of the Swiss Paralympic team

PubMed Central

2013-01-01

Background The aim of this study was to assess airway hyperresponsiveness to eucapnic voluntary hyperventilation and dry powder mannitol challenge in athletes aiming to participate at the Paralympic Games 2008 in Beijing, especially in athletes with spinal cord injury. Methods Forty-four athletes with a disability (27 with paraplegia (group 1), 3 with tetraplegia (group 2) and 14 with other disabilities such as blindness or single limb amputations (group 3) performed spirometry, skin prick testing, measurement of exhaled nitric oxide, eucapnic voluntary hyperventilation challenge test (EVH) and mannitol challenge test (MCT). A fall in FEV1 of ≥10% in either challenge test was deemed positive for exercise-induced bronchoconstriction. Results Fourteen (32%) athletes were atopic and 7 (16%) had a history of physician-diagnosed asthma. Absolute lung function values were significantly lower in patients of group 1 and 2 compared to group 3. Nine (20%) athletes were positive to EVH (8 paraplegics, 1 tetraplegic), and 8 (18%) athletes were positive to MCT (7 paraplegics, 1 tetraplegic). Fourteen (22.7%) subjects were positive to at least one challenge; only three athletes were positive to both tests. None of the athletes in group 3 had a positive test. Both challenge tests showed a significant association with physician-diagnosed asthma status (p = 0.0001). The positive and negative predictive value to diagnose physician-diagnosed asthma was 89% and 91% for EHV, and 75% and 86% for MCT, respectively. Conclusion EVH and MCT can be used to identify, but especially exclude asthma in Paralympic athletes. PMID:23845126

Multi-parameter comparison of a standardized mixed meal tolerance test in healthy and type 2 diabetic subjects: the PhenFlex challenge.

PubMed

Wopereis, Suzan; Stroeve, Johanna H M; Stafleu, Annette; Bakker, Gertruud C M; Burggraaf, Jacobus; van Erk, Marjan J; Pellis, Linette; Boessen, Ruud; Kardinaal, Alwine A F; van Ommen, Ben

2017-01-01

A key feature of metabolic health is the ability to adapt upon dietary perturbations. Recently, it was shown that metabolic challenge tests in combination with the new generation biomarkers allow the simultaneous quantification of major metabolic health processes. Currently, applied challenge tests are largely non-standardized. A systematic review defined an optimal nutritional challenge test, the "PhenFlex test" (PFT). This study aimed to prove that PFT modulates all relevant processes governing metabolic health thereby allowing to distinguish subjects with different metabolic health status. Therefore, 20 healthy and 20 type 2 diabetic (T2D) male subjects were challenged both by PFT and oral glucose tolerance test (OGTT). During the 8-h response time course, 132 parameters were quantified that report on 26 metabolic processes distributed over 7 organs (gut, liver, adipose, pancreas, vasculature, muscle, kidney) and systemic stress. In healthy subjects, 110 of the 132 parameters showed a time course response. Patients with T2D showed 18 parameters to be significantly different after overnight fasting compared to healthy subjects, while 58 parameters were different in the post-challenge time course after the PFT. This demonstrates the added value of PFT in distinguishing subjects with different health status. The OGTT and PFT response was highly comparable for glucose metabolism as identical amounts of glucose were present in both challenge tests. Yet the PFT reports on additional processes, including vasculature, systemic stress, and metabolic flexibility. The PFT enables the quantification of all relevant metabolic processes involved in maintaining or regaining homeostasis of metabolic health. Studying both healthy subjects and subjects with impaired metabolic health showed that the PFT revealed new processes laying underneath health. This study provides the first evidence towards adopting the PFT as gold standard in nutrition research.

Extending the Challenge-Hindrance Model of Occupational Stress: The Role of Appraisal

ERIC Educational Resources Information Center

Webster, Jennica R.; Beehr, Terry A.; Love, Kevin

2011-01-01

Interest regarding the challenge-hindrance occupational stress model has increased in recent years, however its theoretical foundation has not been tested. Drawing from the transactional theory of stress, this study tests the assumptions made in past research (1) that workload and responsibility are appraised as challenges and role ambiguity and…

KSC-2009-6491

NASA Image and Video Library

2009-11-19

CAPE CANAVERAL, Fla. – At the Astronaut Hall of Fame near NASA’s Kennedy Space Center in Florida, Anna Heiney, a Public Affairs support writer with Abacus Technology at Kennedy, tries out a pair of space gloves for their dexterity and flexibility in a glove box at the 2009 Astronaut Glove Challenge, part of NASA’s Centennial Challenges Program. Looking over his shoulder is Kennedy Director Bob Cabana. The nationwide competition focused on developing improved pressure suit gloves for astronauts to use while working in space. During the challenge, the gloves were submitted to burst tests, joint force tests and tests to measure their dexterity and strength during operation in a glove box which simulates the vacuum of space. Centennial Challenges is NASA’s program of technology prizes for the citizen-inventor. The winning prize for the Glove Challenge is $250,000 provided by the Centennial Challenges Program. Photo credit: NASA/Kim Shiflett

Testing Universal Design of a Public Media Website with Diverse Users.

PubMed

Chen, Weiqin; Kessel, Siri; Sanderson, Norun C; Tatara, Naoe

2016-01-01

Testing with users can identify more issues than other testing methods. Many researchers have argued for the importance of user testing in Universal Design. However, testing Universal Design with diverse users poses many challenges. In this paper we will share our experience with testing the Universal Design of a public media website with real users. We discuss the challenges faced and lessons learned in the process.

Mannitol challenge testing for asthma in a community cohort of young adults.

PubMed

White, Elisha C; de Klerk, Nicholas; Hantos, Zoltan; Priston, Monique; Hollams, Elysia M; James, Alan; Sly, Peter D; Holt, Patrick G; Hall, Graham L

2017-05-01

Mannitol challenge testing is an established tool for clinical asthma diagnosis, and can be performed outside of specialized respiratory laboratories. Despite applicability in both clinical and non-clinical populations, with different pre-test asthma probabilities, differences in diagnostic properties have not been well explored. This study aimed to quantify the diagnostic utility of mannitol challenge testing for asthma in a community cohort and a symptomatic wheezing subset of this cohort. During the 22-year follow-up of the Western Australian Pregnancy (Raine) Cohort, 772 participants (384 males) completed mannitol challenge and skin prick testing and respiratory health questionnaires, of whom 148 reporting wheeze in the past 12 months were included in a wheezing subset. Responsiveness to mannitol had low sensitivity (19%) and high specificity (97%) to identify current asthma in the complete cohort, with positive and negative predictive values (PPV and NPV) of 45% and 92%, respectively. Within the wheezing subset, sensitivity (19%) and specificity (94%) remained similar, but PPV increased to 79%, and NPV decreased to 52%. Our findings support previously reported high specificity and good PPV for mannitol challenge testing in symptomatic wheezing populations, and highlight the need for caution when interpreting mannitol test results in non-clinical populations. © 2016 Asian Pacific Society of Respirology.

New validated recipes for double-blind placebo-controlled low-dose food challenges.

PubMed

Winberg, Anna; Nordström, Lisbeth; Strinnholm, Åsa; Nylander, Annica; Jonsäll, Anette; Rönmark, Eva; West, Christina E

2013-05-01

Double-blind placebo-controlled food challenges are considered the most reliable method to diagnose or rule out food allergy. Despite this, there are few validated challenge recipes available. The present study aimed to validate new recipes for low-dose double-blind placebo-controlled food challenges in school children, by investigating whether there were any sensory differences between the active materials containing cow's milk, hen's egg, soy, wheat or cod, and the placebo materials. The challenge materials contained the same hypoallergenic amino acid-based product, with or without added food allergens. The test panels consisted of 275 school children, aged 8-10 and 14-15 yr, respectively, from five Swedish schools. Each participant tested at least one recipe. Standardized blinded triangle tests were performed to investigate whether any sensory differences could be detected between the active and placebo materials. In our final recipes, no significant differences could be detected between the active and placebo materials for any challenge food (p > 0.05). These results remained after stratification for age and gender. The taste of challenge materials was acceptable, and no unfavourable side effects related to test materials were observed. In summary, these new validated recipes for low-dose double-blinded food challenges contain common allergenic foods in childhood; cow's milk, hen's egg, soy, wheat and cod. All test materials contain the same liquid vehicle, which facilitates preparation and dosing. Our validated recipes increase the range of available recipes, and as they are easily prepared and dosed, they may facilitate the use of double-blind placebo-controlled food challenges in daily clinical practice. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Can conjunctival provocation test facilitate the diagnosis of food allergy in children?

PubMed

Krane Kvenshagen, B; Jacobsen, M; Halvorsen, R

2010-01-01

Food allergy is common in children, occurring in 5-7.5%. The diagnosis may, however, be difficult. Elevated IgE or positive skin prick test to a food allergen is often considered proof of allergy, but may represent sensitisation without clinical manifestations. For a precise diagnosis oral challenge is necessary, but this is often not performed because of risk of serious allergic reactions. The aim of this study was to evaluate whether conjunctival provocation test would facilitate the diagnosis of IgE-mediated food allergy. One hundred and forty-nine children with 174 possible diagnoses of food allergy were included. General examination, skin prick test and specific IgE were performed, as well as conjunctival provocation test of the suspected food allergen. Open food challenges and double-blind placebo controlled tests were performed in order to diagnose possible food allergy. Forty-six children with strongly positive conjunctival reactions (rubor, itching, oedema) to fifty food allergens were all proven to have allergy to the food in question. The children with negative conjunctival provocation tests showed no allergic reactions when challenged. We find that a strongly positive conjunctival reaction to a food allergen correlates well with true allergy. An oral challenge should be carefully performed. With a negative conjunctival test an oral challenge may safely be performed. Copyright © 2009 SEICAP. Published by Elsevier Espana. All rights reserved.

Bronchial reactions to exposure to welding fumes.

PubMed Central

Contreras, G R; Chan-Yeung, M

1997-01-01

OBJECTIVES: To study the airway response and its mechanism to welding fumes in six welders with respiratory symptoms. METHODS: Methacholine and welding challenge tests were carried out. The concentration of welding fumes during the exposure test was measured. On two subjects who developed bronchoconstricition to welding challenge, additional tests were carried out including prick, patch, and inhalation challenges with metal salt solutions. RESULTS: Three subjects developed immediate bronchial reaction to exposure to welding fume; one to mild steel and stainless steel welding, another to mild steel and galvanised welding, and one only to galvanised welding. They all had a moderate to pronounced degree of non-specific bronchial hyperresponsiveness. The concentration of fumes during welding tests, particularly to galvanised welding, was high. An inhalation challenge test with zinc chloride salt solution in two subjects who reacted to galvanised welding was negative. Prick and patch tests with zinc chloride were also negative. CONCLUSION: The airway response to welding in these subjects is non-specific and is due to irritation rather than to sensitisation. PMID:9538358

Bronchial reactions to exposure to welding fumes.

PubMed

Contreras, G R; Chan-Yeung, M

1997-11-01

To study the airway response and its mechanism to welding fumes in six welders with respiratory symptoms. Methacholine and welding challenge tests were carried out. The concentration of welding fumes during the exposure test was measured. On two subjects who developed bronchoconstricition to welding challenge, additional tests were carried out including prick, patch, and inhalation challenges with metal salt solutions. Three subjects developed immediate bronchial reaction to exposure to welding fume; one to mild steel and stainless steel welding, another to mild steel and galvanised welding, and one only to galvanised welding. They all had a moderate to pronounced degree of non-specific bronchial hyperresponsiveness. The concentration of fumes during welding tests, particularly to galvanised welding, was high. An inhalation challenge test with zinc chloride salt solution in two subjects who reacted to galvanised welding was negative. Prick and patch tests with zinc chloride were also negative. The airway response to welding in these subjects is non-specific and is due to irritation rather than to sensitisation.

Sensitization to Food Additives in Patients with Allergy: A Study Based on Skin Test and Open Oral Challenge.

PubMed

Moghtaderi, Mozhgan; Hejrati, Zinatosadat; Dehghani, Zahra; Dehghani, Faranak; Kolahi, Niloofar

2016-06-01

There has been a great increase in the consumption of various food additives in recent years. The purpose of this study was to identify the incidence of sensitization to food additives by using skin prick test in patients with allergy and to determine the concordance rate between positive skin tests and oral challenge in hypersensitivity to additives. This cross-sectional study included 125 (female 71, male 54) patients aged 2-76 years with allergy and 100 healthy individuals. Skin tests were performed in both patient and control groups with 25 fresh food additives. Among patients with allergy, 22.4% showed positive skin test at least to one of the applied materials. Skin test was negative to all tested food additives in control group. Oral food challenge was done in 28 patients with positive skin test, in whom 9 patients showed reaction to culprit (Concordance rate=32.1%). The present study suggested that about one-third of allergic patients with positive reaction to food additives showed positive oral challenge; it may be considered the potential utility of skin test to identify the role of food additives in patients with allergy.

Radiation Test Challenges for Scaled Commerical Memories

NASA Technical Reports Server (NTRS)

LaBel, Kenneth A.; Ladbury, Ray L.; Cohn, Lewis M.; Oldham, Timothy

2007-01-01

As sub-100nm CMOS technologies gather interest, the radiation effects performance of these technologies provide a significant challenge. In this talk, we shall discuss the radiation testing challenges as related to commercial memory devices. The focus will be on complex test and failure modes emerging in state-of-the-art Flash non-volatile memories (NVMs) and synchronous dynamic random access memories (SDRAMs), which are volatile. Due to their very high bit density, these device types are highly desirable for use in the natural space environment. In this presentation, we shall discuss these devices with emphasis on considerations for test and qualification methods required.

The space shuttle ascent vehicle aerodynamic challenges configuration design and data base development

NASA Technical Reports Server (NTRS)

Dill, C. C.; Young, J. C.; Roberts, B. B.; Craig, M. K.; Hamilton, J. T.; Boyle, W. W.

1985-01-01

The phase B Space Shuttle systems definition studies resulted in a generic configuration consisting of a delta wing orbiter, and two solid rocket boosters (SRB) attached to an external fuel tank (ET). The initial challenge facing the aerodynamic community was aerodynamically optimizing, within limits, this configuration. As the Shuttle program developed and the sensitivities of the vehicle to aerodynamics were better understood the requirements of the aerodynamic data base grew. Adequately characterizing the vehicle to support the various design studies exploded the size of the data base to proportions that created a data modeling/management challenge for the aerodynamicist. The ascent aerodynamic data base originated primarily from wind tunnel test results. The complexity of the configuration rendered conventional analytic methods of little use. Initial wind tunnel tests provided results which included undesirable effects from model support tructure, inadequate element proximity, and inadequate plume simulation. The challenge to improve the quality of test results by determining the extent of these undesirable effects and subsequently develop testing techniques to eliminate them was imposed on the aerodynamic community. The challenges to the ascent aerodynamics community documented are unique due to the aerodynamic complexity of the Shuttle launch. Never before was such a complex vehicle aerodynamically characterized. The challenges were met with innovative engineering analyses/methodology development and wind tunnel testing techniques.

Noninvasive Fetal ECG: the PhysioNet/Computing in Cardiology Challenge 2013.

PubMed

Silva, Ikaro; Behar, Joachim; Sameni, Reza; Zhu, Tingting; Oster, Julien; Clifford, Gari D; Moody, George B

2013-03-01

The PhysioNet/CinC 2013 Challenge aimed to stimulate rapid development and improvement of software for estimating fetal heart rate (FHR), fetal interbeat intervals (FRR), and fetal QT intervals (FQT), from multichannel recordings made using electrodes placed on the mother's abdomen. For the challenge, five data collections from a variety of sources were used to compile a large standardized database, which was divided into training, open test, and hidden test subsets. Gold-standard fetal QRS and QT interval annotations were developed using a novel crowd-sourcing framework. The challenge organizers used the hidden test subset to evaluate 91 open-source software entries submitted by 53 international teams of participants in three challenge events, estimating FHR, FRR, and FQT using the hidden test subset, which was not available for study by participants. Two additional events required only user-submitted QRS annotations to evaluate FHR and FRR estimation accuracy using the open test subset available to participants. The challenge yielded a total of 91 open-source software entries. The best of these achieved average estimation errors of 187bpm 2 for FHR, 20.9 ms for FRR, and 152.7 ms for FQT. The open data sets, scoring software, and open-source entries are available at PhysioNet for researchers interested on working on these problems.

Economic challenges associated with tuberculosis diagnostic development

PubMed Central

Hanrahan, Colleen F.; Shah, Maunank

2015-01-01

Tuberculosis remains a global health crisis in part due to underdiagnosis. Technological innovations are needed to improve diagnostic test accuracy and reduce the reliance on expensive laboratory infrastructure. However, there are significant economic challenges impeding the development and implementation of new diagnostics. The aim of this piece is to examine the current state of TB diagnostics, outline the unmet needs for new tests, and detail the economic challenges associated with development of new tests from the perspective of developers, policy makers and implementers. PMID:24766367

Economic challenges associated with tuberculosis diagnostic development.

PubMed

Hanrahan, Colleen F; Shah, Maunank

2014-08-01

Tuberculosis remains a global health crisis in part due to underdiagnosis. Technological innovations are needed to improve diagnostic test accuracy and reduce the reliance on expensive laboratory infrastructure. However, there are significant economic challenges impeding the development and implementation of new diagnostics. The aim of this piece is to examine the current state of TB diagnostics, outline the unmet needs for new tests, and detail the economic challenges associated with development of new tests from the perspective of developers, policy makers and implementers.

Universal penetration test apparatus with fluid penetration sensor

DOEpatents

Johnson, Phillip W.; Stampfer, Joseph F.; Bradley, Orvil D.

1999-01-01

A universal penetration test apparatus for measuring resistance of a material to a challenge fluid. The apparatus includes a pad saturated with the challenge fluid. The apparatus includes a compression assembly for compressing the material between the pad and a compression member. The apparatus also includes a sensor mechanism for automatically detecting when the challenge fluid penetrates the material.

KSC-2009-6474

NASA Image and Video Library

2009-11-19

CAPE CANAVERAL, Fla. – This newly designed glove, one of the entries in the 2009 Astronaut Glove Challenge, undergoes a joint force test the 2009 Astronaut Glove Challenge, part of NASA’s Centennial Challenges Program, at the Astronaut Hall of Fame near NASA’s Kennedy Space Center in Florida. The nationwide competition focused on developing improved pressure suit gloves for astronauts to use while working in space. During the challenge, inventors tested the gloves to measure dexterity and strength during operation in a glove box which simulates the vacuum of space. Centennial Challenges is NASA’s program of technology prizes for the citizen-inventor. The winning prize for the Glove Challenge is $250,000 provided by the Centennial Challenges Program. Photo credit: NASA/Kim Shiflett

ERS technical standard on bronchial challenge testing: general considerations and performance of methacholine challenge tests.

PubMed

Coates, Allan L; Wanger, Jack; Cockcroft, Donald W; Culver, Bruce H; Diamant, Zuzana; Gauvreau, Gail; Hall, Graham L; Hallstrand, Teal S; Horvath, Ildiko; de Jongh, Frans H C; Joos, Guy; Kaminsky, David A; Laube, Beth L; Leuppi, Joerg D; Sterk, Peter J

2017-05-01

This international task force report updates general considerations for bronchial challenge testing and the performance of the methacholine challenge test. There are notable changes from prior recommendations in order to accommodate newer delivery devices. Rather than basing the test result upon a methacholine concentration (provocative concentration (PC 20 ) causing a 20% fall in forced expiratory volume in 1 s (FEV 1 )), the new recommendations base the result upon the delivered dose of methacholine causing a 20% fall in FEV 1 (provocative dose (PD 20 )). This end-point allows comparable results from different devices or protocols, thus any suitable nebuliser or dosimeter may be used, so long as the delivery characteristics are known. Inhalation may be by tidal breathing using a breath-actuated or continuous nebuliser for 1 min (or more), or by a dosimeter with a suitable breath count. Tests requiring maximal inhalations to total lung capacity are not recommended because the bronchoprotective effect of a deep breath reduces the sensitivity of the test. Copyright ©ERS 2017.

Prevalence and challenge tests of Listeria monocytogenes in Belgian produced and retailed mayonnaise-based deli-salads, cooked meat products and smoked fish between 2005 and 2007.

PubMed

Uyttendaele, M; Busschaert, P; Valero, A; Geeraerd, A H; Vermeulen, A; Jacxsens, L; Goh, K K; De Loy, A; Van Impe, J F; Devlieghere, F

2009-07-31

Processed ready-to-eat (RTE) foods with a prolonged shelf-life under refrigeration are at risk products for listeriosis. This manuscript provides an overview of prevalence data (n=1974) and challenge tests (n=299) related to Listeria monocytogenes for three categories of RTE food i) mayonnaise-based deli-salads (1187 presence/absence tests and 182 challenge tests), ii) cooked meat products (639 presence/absence tests and 92 challenge tests), and iii) smoked fish (90 presence/absence tests and 25 challenge tests), based on data records obtained from various food business operators in Belgium in the frame of the validation and verification of their HACCP plans over the period 2005-2007. Overall, the prevalence of L. monocytogenes in these RTE foods in the present study was lower compared to former studies in Belgium. For mayonnaise-based deli-salads, in 80 out of 1187 samples (6.7%) the pathogen was detected in 25 g. L. monocytogenes positive samples were often associated with smoked fish deli-salads. Cooked meat products showed a 1.1% (n=639) prevalence of the pathogen. For both food categories, numbers per gram never exceeded 100 CFU. L. monocytogenes was detected in 27.8% (25/90) smoked fish samples, while 4/25 positive samples failed to comply to the 100 CFU/g limit set out in EU Regulation 2073/2005. Challenge testing showed growth potential in 18/182 (9.9%) deli-salads and 61/92 (66%) cooked meat products. Nevertheless, both for deli-salads and cooked meat products, appropriate product formulation and storage conditions based upon hurdle technology could guarantee no growth of L. monocytogenes throughout the shelf-life as specified by the food business operator. Challenge testing of smoked fish showed growth of L. monocytogenes in 12/25 samples stored for 3-4 weeks at 4 degrees C. Of 45 (non-inoculated) smoked fish samples (13 of which were initially positive in 25 g) which were subjected to shelf-life testing, numbers exceeded 100 CFU/g in only one sample after storage until the end of shelf-life. Predictive models, dedicated to and validated for a particular food category, taking into account the inhibitory effect of various factors in hurdle technology, provided predictions of growth potential of L. monocytogenes corresponding to observed growth in challenge testing. Based on the combined prevalence data and growth potential, mayonnaise-based deli-salads and cooked meat products can be classified as intermediate risk foods, smoked fish as a high risk food.

Evaluation of preservative efficacy in pharmaceutical products: the use of psychrotolerant, low-nutrient preferring microbes in challenge tests.

PubMed

Charnock, C; Otterholt, E

2012-10-01

Preservative efficacy in medicines is typically investigated using challenge tests. In such tests, the product is artificially contaminated with a high concentration of standard bacterial and fungal test strains such as Pseudomonas aeruginosa and Candida albicans. The rate and extent of reductions in inoculum viability over a specified period forms the basis for acceptance/rejection of preservative efficacy. None of the strains named for inclusion in the challenge test outlined in the European Pharmacopoeia are associated with the contamination of high-quality water used in pharmaceutical production. Alpha- and Betaproteobacteria are easily the most common microbes in waters intended for pharmaceutical production. In addition, none of the standard test strain panel prefer low-nutrient, dilute conditions or grow at or around refrigeration temperatures. This is important because the water activity and nutrient content of medicines can vary greatly and medicines are often stored cold. We investigate the relevance of these factors when testing preservative efficacy by including other strains in challenge tests. Psychrotolerant, low-nutrient preferring strains (Beta- and Alphaproteobacteria and a yeast) were isolated from pristine waters. These were compared in challenge tests with C. albicans and P. aeruginosa using different storage temperatures. Pharmaceutical products differing widely in water-content, pH and preservative systems were included in the study. Regardless of the type of medicine tested C. albicans always showed superior survival characteristics to the yeast isolate (Cryptococcus terricola). One of the three screened bacterial strains (a Sphingomonas sp.) survived significantly better than P. aeruginosa in all but one product tested. However, the results for all products taken together cannot easily be explained by reference to this strain's psychrotolerancy or its preference for dilute, low-nutrient environments. This study supports previous work indicating that the inclusion of wild-type test strains, in this instance strains that are suited to survival in high-quality waters, improves preservative efficacy tests. Use of a Sphingomonas sp. isolated from a pristine water as a challenge test strain, gave a more stringent indication of preservative efficacy in a wide range of pharmaceuticals than did P. aeruginosa. © 2012 Blackwell Publishing Ltd.

A study of myocardial perfusion in patients with panic disorder and low risk coronary artery disease after 35% CO2 challenge.

PubMed

Fleet, Richard; Foldes-Busque, Guillaume; Grégoire, Jean; Harel, François; Laurin, Catherine; Burelle, Denis; Lavoie, Kim

2014-01-01

We have previously reported that 35% CO2 challenge induced myocardial ischemia in 81% of coronary artery disease (CAD) patients with comorbid panic disorder (PD) and previous positive nuclear exercise stress tests. However, it is yet unclear whether this is the case among CAD patients with PD and normal nuclear exercise stress test results. We hypothesized that a potent mental stressor such as a panic challenge among CAD patients with PD would also induce ischemia in patients with normal exercise stress tests. Forty-one coronary artery disease patients with normal nuclear exercise stress tests (21 patients with PD and 20 without PD) were submitted to a well-established panic challenge test (with 1 vital capacity inhalation of a gas mixture containing 35% CO2 and 65% O2) and injected with Tc-99m-tetrofosmin (Myoview), upon inhalation. Single photon emission computed tomography imaging was used to assess per-panic challenge reversible myocardial ischemia and HR, BP, and a 12 lead ECG was continuously measured during the procedure. Fifty-eight percent of panic disorder patients (12/21) had a panic attack during the panic challenge vs 15% (3/20) of controls (p=0.005). Only 10% of patients in each group displayed myocardial ischemia per panic challenge. These findings suggest that panic attacks among panic disorder patients with lower-risk coronary artery disease may not confer a risk for myocardial ischemia. © 2013.

Food allergy in infants and children: clinical evaluation and management.

PubMed

Levy, Y; Kornbroth, B; Ofer, I; Garty, B Z; Danon, Y L

1994-12-01

A total of 122 infants and children up to age 17 (69 males and 53 females) who were referred for food allergy to the Pediatric Allergy and Clinical Immunology Unit were evaluated by complete history, emphasizing the implicated foods, clinical presentation and involvement of various organ systems, physical examination, and prick skin tests to food allergens. Fourteen infants with a history of egg white allergy and positive skin tests to egg white also underwent skin tests (prick and intradermal in 1:100 dilution) to measles-mumps-rubella (MMR) vaccine; 35 children under 3 years old had 41 oral challenges with the suspected foods; and 9 children over 3 years old had 12 oral challenges with the suspected foods. We found that cow milk/humanized milk formula, egg white, soybean, and peanut are the main allergenic foods in the pediatric population. Thirteen children had 13 positive oral challenges: 12 to cow milk/humanized milk formula and one to egg white. Symptoms reproduced by oral challenges included urticarial and erythematous rash, conjunctival itching, angioedema, abdominal pain, vomiting, diarrhea, and rhinorrhea. No anaphylactic shock was reported. Negative skin test has an excellent predictive accuracy for negative oral challenge with the suspected food in children > 3 years old. The negative predictive accuracy of cow milk skin test in children < 3 years was 73%. Positive skin test is not a good predictor of a clinical reaction to food. Oral food challenge performed cautiously in a medical setting is the "gold standard" for diagnosis. MMR vaccine can be safely administered to infants with egg white allergy after skin tests with the vaccine are performed.

Principles of Work Sample Testing. Volume I: A Non-Empirical Taxonomy of Test Uses; Volume II: Evaluation of Personnel Testing Programs; Volume III: Construction and Evaluation of Work Sample Tests; Volume IV: Generalizability.

ERIC Educational Resources Information Center

Guion, Robert M.; Ironson, Gail H.

Challenges to classical psychometric theory are examined in the context of a broader range of fundamental, derived, and intuitive measurements in psychology; the challenges include content-referenced testing, latent trait theory, and generalizability theory. A taxonomy of psychological measurement is developed, based on: (1) purposes of…

9 CFR 113.309 - Bovine Parainfluenza3 Vaccine.

Code of Federal Regulations, 2011 CFR

2011-01-01

...-challenge for serum antibody studies. (6) Satisfactory Test Criteria: (i) All virus isolations attempts... develop antibody titers of 1:32 or greater by day 6 ±2 days post-challenge. (8) A sequential test... parainfluenza, susceptible calves shall be used as test animals (20 vaccinates and five controls). Blood samples...

9 CFR 113.309 - Bovine Parainfluenza3 Vaccine.

Code of Federal Regulations, 2014 CFR

2014-01-01

...-challenge for serum antibody studies. (6) Satisfactory Test Criteria: (i) All virus isolations attempts... develop antibody titers of 1:32 or greater by day 6 ±2 days post-challenge. (8) A sequential test... parainfluenza, susceptible calves shall be used as test animals (20 vaccinates and five controls). Blood samples...

9 CFR 113.309 - Bovine Parainfluenza3 Vaccine.

Code of Federal Regulations, 2013 CFR

2013-01-01

...-challenge for serum antibody studies. (6) Satisfactory Test Criteria: (i) All virus isolations attempts... develop antibody titers of 1:32 or greater by day 6 ±2 days post-challenge. (8) A sequential test... parainfluenza, susceptible calves shall be used as test animals (20 vaccinates and five controls). Blood samples...

Advanced Electronics Technologies: Challenges for Radiation Effects Testing, Modeling, and Mitigation

NASA Technical Reports Server (NTRS)

LaBel, Kenneth A.; Cohn, Lewis M.

2005-01-01

Emerging Electronics Technologies include: 1) Changes in the commercial semiconductor world; 2) Radiation Effects Sources (A sample test constraint); and 3) Challenges to Radiation Testing and Modeling: a) IC Attributes-Radiation Effects Implication b) Fault Isolation c) Scaled Geometry d) Speed e) Modeling Shortfall f) Knowledge Status

Increasing HIV testing among African immigrants in ireland: challenges and opportunities.

PubMed

Adedimeji, Adebola A; Asibon, Aba; O'Connor, Gerard; Carson, Richard; Cowan, Ethan; McKinley, Philip; Leider, Jason; Mallon, Patrick; Calderon, Yvette

2015-02-01

In 2012, immigrants constitute 63% of new cases of heterosexually transmitted HIV among individuals born outside Ireland. Current strategies to encourage testing can be ineffective if immigrants perceive them as culturally insensitive. We obtained qualitative data to explore challenges to voluntary HIV-testing for immigrants in Ireland. Content analysis was undertaken to identify and describe pertinent themes. Widespread beliefs that HIV is primarily a disease of African immigrants were identified as challenges that constrain access to testing and care. The organization and location of testing services, attitude of health workers, and beliefs regarding mandatory HIV-testing for immigrants seeking access to welfare benefits were also identified. Immigrants in Ireland encounter a variety of structural, cultural and personal constraints to HIV testing. Opportunities exist in the Irish Health system to increase testing among immigrants through greater acknowledgement of cultural sensitivities of immigrant groups.

Affordable Electro-Magnetic Interference (EMI) Testing on Large Space Vehicles

NASA Technical Reports Server (NTRS)

Aldridge, Edward; Curry, Bruce; Scully, Robert

2015-01-01

Objective: Perform System-Level EMI testing of the Orion Exploration Flight Test-1 (EFT-1) spacecraft in situ in the Kennedy Space Center's Neil Armstrong Operations & Checkout (O&C) Facility in 6 days. The only way to execute the system-level EMI testing and meet this schedule challenge was to perform the EMI testing in situ in the Final Assembly & System Test (FAST) Cell in a reverberant mode, not the direct illumination mode originally planned. This required the unplanned construction of a Faraday Cage around the vehicle and FAST Cell structure. The presence of massive steel platforms created many challenges to developing an efficient screen room to contain the RF energy and yield an effective reverberant chamber. An initial effectiveness test showed marginal performance, but improvements implemented afterward resulted in the final test performing surprisingly well! The paper will explain the design, the challenges, and the changes that made the difference in performance!

Laboratory Information Systems in Molecular Diagnostics: Why Molecular Diagnostics Data are Different.

PubMed

Lee, Roy E; Henricks, Walter H; Sirintrapun, Sahussapont J

2016-03-01

Molecular diagnostic testing presents new challenges to information management that are yet to be sufficiently addressed by currently available information systems for the molecular laboratory. These challenges relate to unique aspects of molecular genetic testing: molecular test ordering, informed consent issues, diverse specimen types that encompass the full breadth of specimens handled by traditional anatomic and clinical pathology information systems, data structures and data elements specific to molecular testing, varied testing workflows and protocols, diverse instrument outputs, unique needs and requirements of molecular test reporting, and nuances related to the dissemination of molecular pathology test reports. By satisfactorily addressing these needs in molecular test data management, a laboratory information system designed for the unique needs of molecular diagnostics presents a compelling reason to migrate away from the current paper and spreadsheet information management that many molecular laboratories currently use. This paper reviews the issues and challenges of information management in the molecular diagnostics laboratory.

Universal penetration test apparatus with fluid penetration sensor

DOEpatents

Johnson, P.W.; Stampfer, J.F.; Bradley, O.D.

1999-02-02

A universal penetration test apparatus is described for measuring resistance of a material to a challenge fluid. The apparatus includes a pad saturated with the challenge fluid. The apparatus includes a compression assembly for compressing the material between the pad and a compression member. The apparatus also includes a sensor mechanism for automatically detecting when the challenge fluid penetrates the material. 23 figs.

KSC-2009-6494

NASA Image and Video Library

2009-11-19

CAPE CANAVERAL, Fla. - At the Astronaut Hall of Fame near NASA’s Kennedy Space Center in Florida, the winners of the 2009 Astronaut Glove Challenge, part of NASA’s Centennial Challenges Program, pose for a group photograph with their friends, family and the event organizers. From left are Caroline Homer and her father, Peter Homer, winner of the $250,000 first prize; Alan Hayes, chairman of Volanz Aerospace Inc.; Andy Petro, manager of NASA Centennial Challenges; Ted Southern, winner of the $100,000 second prize; his friend and glove tester Amy Miller; and Paul Secor, Secor Strategies LLC. The nationwide competition focused on developing improved pressure suit gloves for astronauts to use while working in space. During the challenge, the gloves were submitted to burst tests, joint force tests and tests to measure their dexterity and strength during operation in a glove box which simulates the vacuum of space. Centennial Challenges is NASA’s program of technology prizes for the citizen-inventor. The winning prize for the Glove Challenge is $250,000 provided by the Centennial Challenges Program. Photo credit: NASA/Kim Shiflett

Evaluation of colonoscopic allergen provocation as a diagnostic tool in dogs with proven food hypersensitivity reactions.

PubMed

Allenspach, K; Vaden, S L; Harris, T S; Gröne, A; Doherr, M G; Griot-Wenk, M E; Bischoff, S C; Gaschen, F

2006-01-01

To evaluate the colonoscopic allergen provocation (COLAP) test as a new tool for the diagnosis of IgE-mediated food allergy. Oral food challenges as well as COLAP testing were performed in a colony of nine research dogs with proven immediate-type food allergic reactions. In addition, COLAP was performed in five healthy dogs. When compared with the oral challenge test, COLAP accurately determined 18 of 23 (73 per cent) positive oral challenge reactions (73 per cent) in dogs with food allergies and was negative in the healthy dogs. The accuracy of this new test may be higher than that for gastric sensitivity testing. Therefore, COLAP holds promise as a new test to confirm the diagnosis of suspect IgE-mediated food allergy in dogs.

Validation of sterilizing grade filtration.

PubMed

Jornitz, M W; Meltzer, T H

2003-01-01

Validation consideration of sterilizing grade filters, namely 0.2 micron, changed when FDA voiced concerns about the validity of Bacterial Challenge tests performed in the past. Such validation exercises are nowadays considered to be filter qualification. Filter validation requires more thorough analysis, especially Bacterial Challenge testing with the actual drug product under process conditions. To do so, viability testing is a necessity to determine the Bacterial Challenge test methodology. Additionally to these two compulsory tests, other evaluations like extractable, adsorption and chemical compatibility tests should be considered. PDA Technical Report # 26, Sterilizing Filtration of Liquids, describes all parameters and aspects required for the comprehensive validation of filters. The report is a most helpful tool for validation of liquid filters used in the biopharmaceutical industry. It sets the cornerstones of validation requirements and other filtration considerations.

Development and validation of challenge materials for double-blind, placebo-controlled food challenges in children.

PubMed

Vlieg-Boerstra, Berber J; Bijleveld, Charles M A; van der Heide, Sicco; Beusekamp, Berta J; Wolt-Plompen, Saskia A A; Kukler, Jeanet; Brinkman, Joep; Duiverman, Eric J; Dubois, Anthony E J

2004-02-01

The use of double-blind, placebo-controlled food challenges (DBPCFCs) is considered the gold standard for the diagnosis of food allergy. Despite this, materials and methods used in DBPCFCs have not been standardized. The purpose of this study was to develop and validate recipes for use in DBPCFCs in children by using allergenic foods, preferably in their usual edible form. Recipes containing milk, soy, cooked egg, raw whole egg, peanut, hazelnut, and wheat were developed. For each food, placebo and active test food recipes were developed that met the requirements of acceptable taste, allowance of a challenge dose high enough to elicit reactions in an acceptable volume, optimal matrix ingredients, and good matching of sensory properties of placebo and active test food recipes. Validation was conducted on the basis of sensory tests for difference by using the triangle test and the paired comparison test. Recipes were first tested by volunteers from the hospital staff and subsequently by a professional panel of food tasters in a food laboratory designed for sensory testing. Recipes were considered to be validated if no statistically significant differences were found. Twenty-seven recipes were developed and found to be valid by the volunteer panel. Of these 27 recipes, 17 could be validated by the professional panel. Sensory testing with appropriate statistical analysis allows for objective validation of challenge materials. We recommend the use of professional tasters in the setting of a food laboratory for best results.

Food-additive-induced urticaria: a survey of 838 patients with recurrent chronic idiopathic urticaria.

PubMed

Di Lorenzo, Gabriele; Pacor, Maria Luisa; Mansueto, Pasquale; Martinelli, Nicola; Esposito-Pellitteri, Maria; Lo Bianco, Claudia; Ditta, Vito; Leto-Barone, Maria Stefania; Napoli, Nicola; Di Fede, Gaetana; Rini, Giovambattista; Corrocher, Roberto

2005-11-01

Recurrent chronic idiopathic urticaria (RCIU) is a common skin condition that affects 0.1-3% of the population in the USA and Europe and accounts for nearly 75% of all 'ordinary' chronic urticaria (CU) cases. We studied 838 consecutive patients with RCIU referred to hospital between 1998 and 2003. Patients with known causes of CU were excluded. Clinical history, physical examination, and symptom diaries were evaluated during two periods, a diet-free period (1 week) and a food-additive-free diet (FAFD) period (4 weeks), respectively, and two double-blind placebo-controlled (DBPC) challenges of six food additives were administered. The first DBPC challenge included a mixture of the six food additives (DBPCmixed) given to all patients. The second DBPC challenge comprised the single food additives, administered at increasing doses (DBPCsingle) to patients with a positive DBPCmixed test and 105 patients with a negative DBPCmixed test, as a control. The DBPCmixed challenge was positive in 116 patients. None of the 105 control patients had a positive DBPCsingle test. Only 31 DBPCsingle tests were positive in patients with positive DBPCmixed challenge. Twenty-four of the 116 patients showing a positive DBPCmixed challenge also had a positive DBPCsingle result. Our results confirmed that food additive hypersensitivity reactions occurred in few RCIU patients using DBPCsingle challenge. The combination of the results of FAFD and DBPCmixed challenge seems to be of considerable practical interest for allergists, internists and dermatologists, rather than the data of clinical history and the results of DBPCsingle challenge, in patients with RCIU. Copyright (c) 2005 S. Karger AG, Basel.

Occupational asthma induced by cephalosporins.

PubMed

Sastre, J; Quirce, S; Novalbos, A; Lluch-Bernal, M; Bombín, C; Umpiérrez, A

1999-05-01

A 20-yr-old pharmaceutical worker who developed attacks of shortness of breath and wheezing 9 months after beginning work on a process in which cefadroxil powder was bottled or encapsulated will be described. Skin test with cefaxodril was negative. Baseline spirometry and methacholine inhalation test were normal. A controlled bronchial challenge test was carried out in a closed-circuit system with assessment of respirable dust concentration. Exposure to cefadroxil powder at a mean concentration of 10 mg x m(-3) for 10 min elicited an isolated immediate asthmatic response, but no response was observed to control challenge with lactose. Single-blind oral challenge test with amoxicillin up to 500 mg was well tolerated, whereas the oral challenge with cephalexin (25 mg) elicited an immediate asthmatic response. This patient had developed occupational asthma caused by inhalation of cefadroxil as confirmed by specific inhalation test. Since she tolerated oral amoxicillin, a synthetic penicillin with the side-chain identical to that of cefadroxil, it seems that she may be sensitized to the dihydrothiazine ring of cephalosporins.

Eosinophilic airway disease in a patient with a negative skin prick test, but a positive patch test with platinum salts--implications for medical surveillance.

PubMed

Merget, Rolf; Fartasch, Manigé; Sander, Ingrid; Van Kampen, Vera; Raulf, Monika; Brüning, Thomas

2015-09-01

We present the case of a 52-year-old woman with a topic dermatitis since adolescence who developed work-related hand eczema, cough and runny nose 12 years after she had started working as a laboratory technician at a precious metals refinery. While skin prick test with sodium hexachloroplatinate (SPTPt ) was negative, patch testing with ammonium tetrachloroplatinate was positive after 24, 48, 72, and 96 hr. Inhalation challenge with sodium hexachloroplatinate yielded cough, mild shortness of breath, and a maximal decrease of FEV1 of 8% from baseline 24 hr after the challenge. Significant increases of bronchial hyperresponsiveness, exhaled nitric monoxide and sputum eosinophils were documented after the challenge. We conclude that eosinophilic airway disease due to platinum salts may occur in SPTPt negative subjects. Both, patch testing and inhalation challenge with platinum salts should be considered in SPT negative subjects with occupational exposure to precious metal salts and work-related allergic symptoms. © 2015 Wiley Periodicals, Inc.

USDA regulatory guidelines and practices for veterinary Leptospira vaccine potency testing.

PubMed

Srinivas, G B; Walker, A; Rippke, B

2013-09-01

Batch-release potency testing of leptospiral vaccines licensed by the United States Department of Agriculture (USDA) historically was conducted through animal vaccination-challenge models. The hamster vaccination-challenge assay was Codified in 1974 for bacterins containing Leptospira pomona, Leptospira icterohaemorrhagiae, and Leptospira canicola, and in 1975 for bacterins containing Leptospira grippotyphosa. In brief, 10 hamsters are vaccinated with a specified dilution of bacterin. After a holding period, the vaccinated hamsters, as well as nonvaccinated controls, are challenged with virulent Leptospira and observed for mortality. Eighty percent of vaccinated hamsters must survive in the face of a valid challenge. The high cost of the Codified tests, in terms of monetary expense and animal welfare, prompted the Center for Veterinary Biologics (CVB) to develop ELISA alternatives for them. Potency tests for other serogroups, such as Leptospira hardjo-bovis, that do not have Codified requirements for potency testing continue to be examined on a case-by-case basis. Published by Elsevier Ltd.

A Structured Career Intervention Program for Academically Challenged Students

ERIC Educational Resources Information Center

Salleh, Amla; Abdullah, Syed Mohamad; Mahmud, Zuria; Ghavifekr, Simin; Ishak, Noriah

2013-01-01

A study was carried out to test the effects of a 2-week structured intervention program on academically challenged students' career development. A quasi-experimental study was designed using pre-tests, post-tests, and a control group approach to examine the effects of the intervention program. Data were collected from both the experimental and…

Computer-Based Signing Accommodations: Comparing a Recorded Human with an Avatar

ERIC Educational Resources Information Center

Russell, Michael; Kavanaugh, Maureen; Masters, Jessica; Higgins, Jennifer; Hoffmann, Thomas

2009-01-01

Many students who are deaf or hard-of-hearing are eligible for a signing accommodation for state and other standardized tests. The signing accommodation, however, presents several challenges for testing programs that attempt to administer tests under standardized conditions. One potential solution for many of these challenges is the use of…

Continuing challenges for computer-based neuropsychological tests.

PubMed

Letz, Richard

2003-08-01

A number of issues critical to the development of computer-based neuropsychological testing systems that remain continuing challenges to their widespread use in occupational and environmental health are reviewed. Several computer-based neuropsychological testing systems have been developed over the last 20 years, and they have contributed substantially to the study of neurologic effects of a number of environmental exposures. However, many are no longer supported and do not run on contemporary personal computer operating systems. Issues that are continuing challenges for development of computer-based neuropsychological tests in environmental and occupational health are discussed: (1) some current technological trends that generally make test development more difficult; (2) lack of availability of usable speech recognition of the type required for computer-based testing systems; (3) implementing computer-based procedures and tasks that are improvements over, not just adaptations of, their manually-administered predecessors; (4) implementing tests of a wider range of memory functions than the limited range now available; (5) paying more attention to motivational influences that affect the reliability and validity of computer-based measurements; and (6) increasing the usability of and audience for computer-based systems. Partial solutions to some of these challenges are offered. The challenges posed by current technological trends are substantial and generally beyond the control of testing system developers. Widespread acceptance of the "tablet PC" and implementation of accurate small vocabulary, discrete, speaker-independent speech recognition would enable revolutionary improvements to computer-based testing systems, particularly for testing memory functions not covered in existing systems. Dynamic, adaptive procedures, particularly ones based on item-response theory (IRT) and computerized-adaptive testing (CAT) methods, will be implemented in new tests that will be more efficient, reliable, and valid than existing test procedures. These additional developments, along with implementation of innovative reporting formats, are necessary for more widespread acceptance of the testing systems.

Safely diagnosing clinically significant penicillin allergy using only penicilloyl-poly-lysine, penicillin, and oral amoxicillin.

PubMed

Macy, Eric; Ngor, Eunis W

2013-01-01

Penicillin skin testing is rarely used to undiagnose penicillin "allergy" in the United States, partially because of concern that commercially available materials are inadequate. We determined whether skin testing with only commercially available penicilloyl-poly-lysine and penicillin followed by an oral amoxicillin challenge, if skin test-negative, can safely identify clinically significant penicillin allergy. Five hundred sequential persons with positive history of penicillin "allergy" were evaluated by skin testing with penicilloyl-poly-lysine and penicillin between June 8, 2010, and March 29, 2012. All persons with negative skin tests were given an oral amoxicillin challenge and observed for 1 hour. Persons undergoing penicillin allergy testing were representative of all health plan members with penicillin allergy. Only 4 persons (0.8%; 95% CI, 0.32%-2.03%) had a positive skin test result. Only 4 persons (0.8%; 95% CI, 0.32%-2.03%) had an acute objective oral amoxicillin challenge reaction. Fifteen persons (3.0%; 95% CI, 1.83%-4.98%) had subjective oral challenge reactions, either acute transient itching or dizziness. All were women and 11 (73.3%) had multiple drug intolerance syndrome. None had severe reactions or objective signs. These were not considered to be positive challenge reactions. Sixty-eight subjects (13.6%) who were negative on testing were exposed to 88 courses of penicillins during 90 days of follow-up. New reactions were reported after 4 courses (4.5%), 3 (75%) occurring in subjects with multiple drug intolerance syndrome. Penicillin skin testing, using only penicilloyl-poly-lysine and penicillin, followed by oral amoxicillin challenge, if negative, can safely identify clinically significant IgE-mediated penicillin allergy in patients who use health care in the United States at this time. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

New Mass Properties Engineers Aerospace Ballasting Challenge Facilitated by the SAWE Community

NASA Technical Reports Server (NTRS)

Cutright, Amanda; Shaughnessy, Brendan

2010-01-01

The discipline of Mass Properties Engineering tends to find the engineers; not typically vice versa. In this case, two engineers quickly found their new responsibilities deep in many aspects of mass properties engineering and required to meet technical challenges in a fast paced environment. As part of NASA's Constellation Program, a series of flight tests will be conducted to evaluate components of the new spacecraft launch vehicles. One of these tests is the Pad Abort 1 (PA-1) flight test which will test the Launch Abort System (LAS), a system designed to provide escape for astronauts in the event of an emergency. The Flight Test Articles (FTA) used in this flight test are required to match mass properties corresponding to the operational vehicle, which has a continually evolving design. Additionally, since the structure and subsystems for the Orion Crew Module (CM) FTA are simplified versions of the final product, thousands of pounds of ballast are necessary to achieve the desired mass properties. These new mass properties engineers are responsible for many mass properties aspects in support of the flight test, including meeting the ballasting challenge for the CM Boilerplate FTA. SAWE expert and experienced mass properties engineers, both those that are directly on the team and many that supported via a variety of Society venues, significantly contributed to facilitating the success of addressing this particular mass properties ballasting challenge, in addition to many other challenges along the way. This paper discusses the details regarding the technical aspects of this particular mass properties challenge, as well as identifies recommendations for new mass properties engineers that were learned from the SAWE community along the way.

Immediate hypersensitivity to iodinated contrast media: diagnostic accuracy of skin tests and intravenous provocation test with low dose.

PubMed

Sesé, L; Gaouar, H; Autegarden, J-E; Alari, A; Amsler, E; Vial-Dupuy, A; Pecquet, C; Francès, C; Soria, A

2016-03-01

The diagnosis of HSR to iodinated contrast media (ICM) is challenging based on clinical history and skin tests. This study evaluates the negative predictive value (NPV) of skin tests and intravenous provocation test (IPT) with low-dose ICM in patients with suspected immediate hypersensitivity reaction (HSR) to ICM. Thirty-seven patients with suspected immediate hypersensitivity reaction to ICM were included retrospectively. Skin tests and a single-blind placebo-controlled intravenous provocation test (IPT) with low-dose iodinated contrast media (ICM) were performed. Skin tests with ICM were positive in five cases (one skin prick test and five intradermal test). Thirty-six patients were challenged successfully by IPT, and only one patient had a positive challenge result, with a grade I reaction by the Ring and Messmer classification. Ten of 23 patients followed up by telephone were re-exposed to a negative tested ICM during radiologic examination; two experienced a grade I immediate reaction. For immediate hypersensitivity reaction to ICM, the NPV for skin tests and IPT with low dose was 80% (95% CI 44-97%). © 2016 John Wiley & Sons Ltd.

Experimental intramammary inoculation with Mycoplasma bovis in vaccinated and unvaccinated cows: effect on milk production and milk quality.

PubMed Central

Boothby, J T; Jasper, D E; Thomas, C B

1986-01-01

The effect of vaccination on milk production was evaluated in vaccinated and control cows experimentally challenged in two of four quarters with live Mycoplasma bovis. During the first three weeks after experimental challenge, six of eight unchallenged quarters on vaccinated cows and seven of eight unchallenged quarters on control cows became infected. Most of these quarters secreted normal milk, with negative California Mastitis Test scores and maintained normal milk production throughout most of the study (although some quarters on control cows remained infected). All challenged quarters became infected, had strong California Mastitis Test reactions, and had a drastic (greater than 85%) loss in milk production. Thereafter, four of eight challenged quarters on control cows remained infected, had mostly positive California Mastitis Test scores, produced mostly normal-appearing milk, and recovered some productive capabilities. By the end of the study no M. bovis could be recovered from challenged quarters on vaccinated cows and the milk appeared mostly normal. The California Mastitis Test scores on these quarters, however, remained elevated and milk production remained very low. PMID:3756674

Predicting hypoxaemia during flights in children with cystic fibrosis

PubMed Central

Buchdahl, R; Babiker, A; Bush, A; Cramer, D

2001-01-01

BACKGROUND—We have previously suggested that it is possible to predict oxygen desaturation during flight in children with cystic fibrosis and chronic lung disease by non-invasive measurement of oxygen saturation following inhalation of 15% oxygen—the pre-flight hypoxic challenge. This study reports on the results of measurements over 5years.
METHODS—The study comprised a pre-flight hypoxic challenge measuring oxygen saturation by finger tip pulse oximetry (SpO2) during tidal breathing of 15% oxygen in nitrogen and spirometric testing 1 month before the flight followed by SpO2 measurements during intercontinental flights to and from holidays abroad with children in wake and sleep states.
RESULTS—Pre-flight tests were completed on 87 children with cystic fibrosis. Desaturation of <90% occurred in 10 children at some stage during the flight, three of whom received supplementary oxygen. Using a cut off SpO2 of 90%, the pre-flight hypoxic challenge correctly predicted desaturation in only two of these children. The sensitivity and specificity of the pre-flight hypoxic challenge were 20% and 99%, respectively, compared with 70% and 96% for spirometric tests (using a cut off for forced expiratory volume in 1 second (FEV1) of <50% predicted). Overall, pre-flight spirometric tests were a better predictor of desaturation during flight with the area under the Receiver Operating Characteristic (ROC) curve of 0.89 compared with 0.73 for the hypoxic challenge test.
CONCLUSIONS—In this group of subjects pre-flight spirometric testing was a better predictor of desaturation during flight than the pre-flight hypoxic challenge.

 PMID:11641514

Levodopa-Induced Changes in Electromyographic Patterns in Patients with Advanced Parkinson’s Disease

PubMed Central

Ruonala, Verneri; Pekkonen, Eero; Airaksinen, Olavi; Kankaanpää, Markku; Karjalainen, Pasi A; Rissanen, Saara M

2018-01-01

Levodopa medication is the most efficient treatment for motor symptoms of Parkinson’s disease (PD). Levodopa significantly alleviates rigidity, rest tremor, and bradykinesia in PD. The severity of motor symptoms can be graded with UPDRS-III scale. Levodopa challenge test is routinely used to assess patients’ eligibility to deep-brain stimulation (DBS) in PD. Feasible and objective measurements to assess motor symptoms of PD during levodopa challenge test would be helpful in unifying the treatment. Twelve patients with advanced PD who were candidates for DBS treatment were recruited to the study. Measurements were done in four phases before and after levodopa challenge test. Rest tremor and rigidity were evaluated using UPDRS-III score. Electromyographic (EMG) signals from biceps brachii and kinematic signals from forearm were recorded with wireless measurement setup. The patients performed two different tasks: arm isometric tension and arm passive flexion–extension. The electromyographic and the kinematic signals were analyzed with parametric, principal component, and spectrum-based approaches. The principal component approach for isometric tension EMG signals showed significant decline in characteristics related to PD during levodopa challenge test. The spectral approach on passive flexion–extension EMG signals showed a significant decrease on involuntary muscle activity during the levodopa challenge test. Both effects were stronger during the levodopa challenge test compared to that of patients’ personal medication. There were no significant changes in the parametric approach for EMG and kinematic signals during the measurement. The results show that a wireless and wearable measurement and analysis can be used to study the effect of levodopa medication in advanced Parkinson’s disease. PMID:29459845

The challenge of developmentally appropriate care: predictive genetic testing in young people for familial adenomatous polyposis.

PubMed

Duncan, Rony E; Gillam, Lynn; Savulescu, Julian; Williamson, Robert; Rogers, John G; Delatycki, Martin B

2010-03-01

Predictive genetic tests for familial adenomatous polyposis (FAP) are routinely offered to young people during early adolescence. While this is not controversial, due to the medical benefit conferred by the test, it is nonetheless challenging as a consequence of the stage of life of the young people, and the simultaneous involvement of multiple family members. Despite these challenges, it is possible to ensure that the test is offered in such a way that it actively acknowledges and facilitates young people's developing autonomy and psychosocial well-being. In this paper we present findings from ten in-depth interviews with young people who have undergone predictive genetic testing for FAP (four male, six female; five gene-positive, five gene-negative; aged 10-17 years at the time of their predictive test; aged 12-25 years at the time of their research interview). We present five themes that emerged from the interviews which highlight key ethical challenges associated with such testing. These are: (1) the significance of the test; (2) young people's lack of involvement in the decision to be tested; (3) young people's limited understanding; (4) provision of the blood test at the first visit; and (5) group testing of family members. We draw on these themes to make eight recommendations for future practice. Together, these recommendations highlight the importance of providing developmentally appropriate care to young people undergoing predictive genetic testing for FAP.

Repeated Challenge Studies: A Comparison of Union-Intersection Testing with Linear Modeling.

ERIC Educational Resources Information Center

Levine, Richard A.; Ohman, Pamela A.

1997-01-01

Challenge studies can be used to see whether there is a causal relationship between an agent of interest and a response. An approach based on union-intersection testing is presented that allows researchers to examine observations on a single subject and test the hypothesis of interest. An application using psychological data is presented. (SLD)

Wireless Instrumentation Systems for Flight Testing at NASA AFRC

NASA Technical Reports Server (NTRS)

Hang, Richard

2017-01-01

NASA Armstrong Flight Research Center is revolutionizing its traditional wired instrumentation systems with wireless technologies. This effort faces many technical challenges, such as spectrum compliance, time synchronization, power distribution and airworthiness. This presentation summarizes NASA AFRC's flight test capabilities with current conventional instrumentation methodology and highlights the technical challenges of wireless systems used for flight test research applications.

Radiation Testing on State-of-the-Art CMOS: Challenges, Plans, and Preliminary Results

NASA Technical Reports Server (NTRS)

LaBel, Kenneth A.; Cohn, Lewis M.

2009-01-01

At GOMAC 2007 and 2008, we discussed a variety of challenges for radiation testing of modern semiconductor devices and technologies [1, 2]. In this presentation, we provide more specific details in this on-going investigation focusing on out-of-the-box lessons observed for providing radiation effects assurances as well as preliminary test results.

Immunologic responses against hydrolyzed soy protein in dogs with experimentally induced soy hypersensitivity.

PubMed

Puigdemont, Anna; Brazís, Pilar; Serra, Montserrat; Fondati, Alessandra

2006-03-01

To assess whether dogs with experimentally induced type I hypersensitivity against soy protein would respond to soy hydrolysate and develop cutaneous or gastrointestinal tract reactions after intradermal and oral challenge exposure. 12 naïve Beagle pups (9 sensitized and 3 control dogs). 9 dogs were sensitized against soy protein by administration of allergens during a 90-day period. After the sensitization period, serum concentrations of soy-specific IgE were determined and an intradermal test was performed to confirm the dogs were sensitized against soy protein. An intradermal challenge test and an oral challenge test with native and hydrolyzed soy protein were conducted on 6 sensitized and 2 control dogs. High serum concentrations of soy-specific IgE and positive results for the intradermal test were observed for the 9 sensitized dogs after completion of the sesitization process. Sensitized dogs challenge exposed with hydrolyzed soy protein had a reduced inflammatory response after intradermal injection and no clinical response after an oral challenge exposure, compared with responses after intradermal and oral challenge exposure with native soy protein. Soy-sensitized dogs did not respond to oral administration of hydrolyzed soy protein. Thus, hydrolyzed soy protein may be useful in diets formulated for the management of dogs with adverse reactions to food.

Reducing animal experimentation in foot-and-mouth disease vaccine potency tests.

PubMed

Reeve, Richard; Cox, Sarah; Smitsaart, Eliana; Beascoechea, Claudia Perez; Haas, Bernd; Maradei, Eduardo; Haydon, Daniel T; Barnett, Paul

2011-07-26

The World Organisation for Animal Health (OIE) Terrestrial Manual and the European Pharmacopoeia (EP) still prescribe live challenge experiments for foot-and-mouth disease virus (FMDV) immunogenicity and vaccine potency tests. However, the EP allows for other validated tests for the latter, and specifically in vitro tests if a "satisfactory pass level" has been determined; serological replacements are also currently in use in South America. Much research has therefore focused on validating both ex vivo and in vitro tests to replace live challenge. However, insufficient attention has been given to the sensitivity and specificity of the "gold standard"in vivo test being replaced, despite this information being critical to determining what should be required of its replacement. This paper aims to redress this imbalance by examining the current live challenge tests and their associated statistics and determining the confidence that we can have in them, thereby setting a standard for candidate replacements. It determines that the statistics associated with the current EP PD(50) test are inappropriate given our domain knowledge, but that the OIE test statistics are satisfactory. However, it has also identified a new set of live animal challenge test regimes that provide similar sensitivity and specificity to all of the currently used OIE tests using fewer animals (16 including controls), and can also provide further savings in live animal experiments in exchange for small reductions in sensitivity and specificity. Copyright © 2011 Elsevier Ltd. All rights reserved.

Opportunities and strategies to further reduce animal use for Leptospira vaccine potency testing.

PubMed

Walker, A; Srinivas, G B

2013-09-01

Hamsters are routinely infected with virulent Leptospira for two purposes in the regulation of biologics: the performance of Codified potency tests and maintenance of challenge culture for the Codified potency tests. Options for reducing animal use in these processes were explored in a plenary lecture at the "International Workshop on Alternative Methods for Leptospira Vaccine Potency Testing: State of the Science and the Way Forward" held at the Center for Veterinary Biologics in September 2012. The use of validated in vitro potency assays such as those developed by the U.S. Department of Agriculture for Leptospira (L.) canicola, Leptospira grippotyphosa, Leptospira pomona, and Leptospira icterohaemorrhagiae rather than the Codified hamster vaccination-challenge assay was encouraged. Alternatives such as reduced animal numbers in the hamster vaccination-challenge testing were considered for problematic situations. Specifically, the merits of sharing challenge controls, reducing group sizes, and eliminating animals for concurrent challenge dose titration were assessed. Options for maintaining virulent, stable cultures without serial passage through hamsters or with decreased hamster use were also discussed. The maintenance of virulent Leptospira without the use of live animals is especially difficult since a reliable means to maintain virulence after multiple in vitro passages has not yet been identified. Published by Elsevier Ltd.

Evaluation of Food Allergy in Children by Skin Prick Tests with Commercial Extracts and Fresh Foods, Specific IgE and, Open Oral Food Challenge-Our Five Years Experience in Food Allergy Work-up.

PubMed

Zivanovic, Mirjana; Atanasković-Marković, Marina; Medjo, Biljana; Gavrović-Jankulović, Marija; Smiljanić, Katarina; Tmušić, Vladimir; Djurić, Vojislav

2017-04-01

IgE- mediated food allergy affects 6-8% of children. Our study aimed to define the correlations between the results obtained with skin prick tests (SPTs) using commercial extracts and fresh foods, and the correlations between these result and those obtained with specific IgE (sIgE) and/ or challenge. Children aged from 2 months to 6 years were recruited prospectively. Overall 571 children were positive to one food. In all children we performed  SPT using commercial extracts of suspected food and fresh foods and sIgE. If SPT and sIgE test results did not correspond to the history, we performed open oral food challenge. Sensitivity of SPT with commercial extracts for all tested food was poor (3-35%), while  sensitivity of fresh food skin prick tests (FFSPT) was excellent (50-100%), and showed correlation with open oral food challenge (p<0.001). Our results suggest that fresh food extracts are more effective in detecting sensitization and with levels of sIgE greater than class 3 could predict clinical reactivity, without the need for potentially hazardous food challenges.

Microbiological Challenge Testing for Listeria Monocytogenes in Ready-to-Eat Food: A Practical Approach.

PubMed

Spanu, Carlo; Scarano, Christian; Ibba, Michela; Pala, Carlo; Spanu, Vincenzo; De Santis, Enrico Pietro Luigi

2014-12-09

Food business operators (FBOs) are the primary responsible for the safety of food they place on the market. The definition and validation of the product's shelf-life is an essential part for ensuring microbiological safety of food and health of consumers. In the frame of the Regulation (EC) No 2073/2005 on microbiological criteria for foodstuffs, FBOs shall conduct shelf-life studies in order to assure that their food does not exceed the food safety criteria throughout the defined shelf-life. In particular this is required for ready-to-eat (RTE) food that supports the growth of Listeria monocytogenes . Among other studies, FBOs can rely on the conclusion drawn by microbiological challenge tests. A microbiological challenge test consists in the artificial contamination of a food with a pathogen microorganism and aims at simulating its behaviour during processing and distribution under the foreseen storage and handling conditions. A number of documents published by international health authorities and research institutions describes how to conduct challenge studies. The authors reviewed the existing literature and described the methodology for implementing such laboratory studies. All the main aspects for the conduction of L. monocytogenes microbiological challenge tests were considered, from the selection of the strains, preparation and choice of the inoculum level and method of contamination, to the experimental design and data interpretation. The objective of the present document is to provide an exhaustive and practical guideline for laboratories that want to implement L. monocytogenes challenge testing on RTE food.

Microbiological Challenge Testing for Listeria Monocytogenes in Ready-to-Eat Food: A Practical Approach

PubMed Central

Scarano, Christian; Ibba, Michela; Pala, Carlo; Spanu, Vincenzo; De Santis, Enrico Pietro Luigi

2014-01-01

Food business operators (FBOs) are the primary responsible for the safety of food they place on the market. The definition and validation of the product’s shelf-life is an essential part for ensuring microbiological safety of food and health of consumers. In the frame of the Regulation (EC) No 2073/2005 on microbiological criteria for foodstuffs, FBOs shall conduct shelf-life studies in order to assure that their food does not exceed the food safety criteria throughout the defined shelf-life. In particular this is required for ready-to-eat (RTE) food that supports the growth of Listeria monocytogenes. Among other studies, FBOs can rely on the conclusion drawn by microbiological challenge tests. A microbiological challenge test consists in the artificial contamination of a food with a pathogen microorganism and aims at simulating its behaviour during processing and distribution under the foreseen storage and handling conditions. A number of documents published by international health authorities and research institutions describes how to conduct challenge studies. The authors reviewed the existing literature and described the methodology for implementing such laboratory studies. All the main aspects for the conduction of L. monocytogenes microbiological challenge tests were considered, from the selection of the strains, preparation and choice of the inoculum level and method of contamination, to the experimental design and data interpretation. The objective of the present document is to provide an exhaustive and practical guideline for laboratories that want to implement L. monocytogenes challenge testing on RTE food. PMID:27800369

Allergy to cow's milk proteins: what contribution does hypersensitivity in skin tests have to this diagnosis?

PubMed

Costa, Aldo José Fernandes; Sarinho, Emanuel Sávio Cavalcanti; Motta, Maria Eugênia Farias Almeida; Gomes, Priscila Nogueira; de Oliveira de Melo, Sabrina Maria; da Silva, Giselia Alves Pontes

2011-02-01

Food allergy is an immunologically mediated adverse reaction to food protein. Cow's milk protein allergy (CMPA) is the most frequent type and is the one that is most difficult to diagnose. This study had the objective of analyzing the accuracy of hypersensitivity and specific IgE skin tests among children with CMPA and predominantly gastrointestinal clinical manifestations. The participants in this study were 192 children aged one and five (median of 2 yr). Among these, 122 underwent open oral challenge to the suspected food. After evaluating the sensitivity, specificity and positive and negative predictive values (respectively, PPV and NPV) of skin and specific IgE tests in relation to the gold standard (open oral challenge); all the children underwent the skin prick test (SPT), specific IgE test and atopy patch test (APT) for cow's milk, eggs, wheat and peanuts and the open oral challenge for the food to which the child was sensitive or had suspected sensitivity. Presence of food allergy was confirmed for 50 children (40.9%). Among these cases, 44/50 (88%) were of allergy to cow's milk protein. Children who presented a positive response to an oral challenge to cow's milk protein were considered to be cases, while the controls were children with negative response. Twenty-two of the 44 cases (50.0%) presented symptoms within the first 4 h after the challenge. The SPT presented 31.8% sensitivity, 90.3% specificity, 66.7% PPV and 68.4% NPV. The APT presented 25.0% sensitivity, 81.9% specificity, 45.8% PPV and 64.1% NPV. The specific IgE test presented, respectively, 20.5%, 88.9%, 52.9% and 64.6%. Despite the operational difficulty and the possible exposure risk, oral challenge is the best method for diagnosing CMPA, because of the low sensitivity and PPV of skin and specific IgE tests. © 2011 John Wiley & Sons A/S.

Implementation Considerations for Multisite Clinical Trials with Cognitive Neuroscience Tasks

PubMed Central

Keefe, Richard S. E.; Harvey, Philip D.

2008-01-01

Multisite clinical trials aimed at cognitive enhancement across various neuropsychiatric conditions have employed standard neuropsychological tests as outcome measures. While these tests have enjoyed wide clinical use and have proven reliable and predictive of functional disability, a number of implementation challenges have arisen when these tests are used in clinical trials. These issues are likely to be magnified in future studies when cognitive neuroscience (CN) procedures are explored in these trials, because in their current forms CN procedures are less standardized and more difficult to teach and monitor. For multisite trials, we anticipate that the most challenging issues will include assuring tester competence, monitoring tester performance, specific challenges with complex assessment methods, and having resources available for adequate monitoring of data quality. Suggestions for overcoming these implementation challenges are offered. PMID:18495645

Anticipating the Ethical Challenges of Psychiatric Genetic Testing.

PubMed

Appelbaum, Paul S; Benston, Shawna

2017-07-01

Genetic testing for mental illness is likely to become increasingly prevalent as the science behind it is refined. This article identifies anticipated ethical challenges for patients, psychiatrists, and genetic counselors and makes recommendations for addressing them. Many of the ethical challenges of psychiatric genetic testing are likely to stem from failures to comprehend the nature and implications of test results. Recent studies have identified gaps in the knowledge base of psychiatrists and genetic counselors, which limit their abilities to provide patients with appropriate education. A small number of studies have demonstrated the value of counseling in empowering patients to deal with relevant genetic information. Psychiatrists and other health professionals must be able to assist patients and families in making informed decisions about genetic testing and interpreting test results. Filling their knowledge gaps on these issues will be a critical step towards meeting these responsibilities.

Lessons in the Design and Characterization Testing of the Semi-Span Super-Sonic Transport (S4T) Wind-Tunnel Model

NASA Technical Reports Server (NTRS)

2012-01-01

This paper focuses on some of the more challenging design processes and characterization tests of the Semi-Span Super-Sonic Transport (S4T)-Active Controls Testbed (ACT). The model was successfully tested in four entries in the National Aeronautics and Space Administration Langley Transonic Dynamics Tunnel to satisfy the goals and objectives of the Fundamental Aeronautics Program Supersonic Project Aero-Propulso-Servo-Elastic effort. Due to the complexity of the S4T-ACT, only a small sample of the technical challenges for designing and characterizing the model will be presented. Specifically, the challenges encountered in designing the model include scaling the Technology Concept Airplane to model scale, designing the model fuselage, aileron actuator, and engine pylons. Characterization tests included full model ground vibration tests, wing stiffness measurements, geometry measurements, proof load testing, and measurement of fuselage static and dynamic properties.

Development of an objective gene expression panel as an alternative to self-reported symptom scores in human influenza challenge trials.

PubMed

Muller, Julius; Parizotto, Eneida; Antrobus, Richard; Francis, James; Bunce, Campbell; Stranks, Amanda; Nichols, Marshall; McClain, Micah; Hill, Adrian V S; Ramasamy, Adaikalavan; Gilbert, Sarah C

2017-06-08

Influenza challenge trials are important for vaccine efficacy testing. Currently, disease severity is determined by self-reported scores to a list of symptoms which can be highly subjective. A more objective measure would allow for improved data analysis. Twenty-one volunteers participated in an influenza challenge trial. We calculated the daily sum of scores (DSS) for a list of 16 influenza symptoms. Whole blood collected at baseline and 24, 48, 72 and 96 h post challenge was profiled on Illumina HT12v4 microarrays. Changes in gene expression most strongly correlated with DSS were selected to train a Random Forest model and tested on two independent test sets consisting of 41 individuals profiled on a different microarray platform and 33 volunteers assayed by qRT-PCR. 1456 probes are significantly associated with DSS at 1% false discovery rate. We selected 19 genes with the largest fold change to train a random forest model. We observed good concordance between predicted and actual scores in the first test set (r = 0.57; RMSE = -16.1%) with the greatest agreement achieved on samples collected approximately 72 h post challenge. Therefore, we assayed samples collected at baseline and 72 h post challenge in the second test set by qRT-PCR and observed good concordance (r = 0.81; RMSE = -36.1%). We developed a 19-gene qRT-PCR panel to predict DSS, validated on two independent datasets. A transcriptomics based panel could provide a more objective measure of symptom scoring in future influenza challenge studies. Trial registration Samples were obtained from a clinical trial with the ClinicalTrials.gov Identifier: NCT02014870, first registered on December 5, 2013.

High-Stakes Testing in the Warm Heart of Africa: The Challenges and Successes of the Malawi National Examinations Board

ERIC Educational Resources Information Center

Chakwera, Elias; Khembo, Dafter; Sireci, Stephen G.

2004-01-01

In the United States, tests are held to high standards of quality. In developing countries such as Malawi, psychometricians must deal with these same high standards as well as several additional pressures such as widespread cheating, test administration difficulties due to challenging landscapes and poor resources, difficulties in reliably scoring…

Measuring Ability, Speed, or Both? Challenges, Psychometric Solutions, and What Can Be Gained from Experimental Control

ERIC Educational Resources Information Center

Goldhammer, Frank

2015-01-01

The main challenge of ability tests relates to the difficulty of items, whereas speed tests demand that test takers complete very easy items quickly. This article proposes a conceptual framework to represent how performance depends on both between-person differences in speed and ability and the speed-ability compromise within persons. Related…

Practical challenges related to point of care testing.

PubMed

Shaw, Julie L V

2016-04-01

Point of care testing (POCT) refers to laboratory testing that occurs near to the patient, often at the patient bedside. POCT can be advantageous in situations requiring rapid turnaround time of test results for clinical decision making. There are many challenges associated with POCT, mainly related to quality assurance. POCT is performed by clinical staff rather than laboratory trained individuals which can lead to errors resulting from a lack of understanding of the importance of quality control and quality assurance practices. POCT is usually more expensive than testing performed in the central laboratory and requires a significant amount of support from the laboratory to ensure the quality testing and meet accreditation requirements. Here, specific challenges related to POCT compliance with accreditation standards are discussed along with strategies that can be used to overcome these challenges. These areas include: documentation of POCT orders, charting of POCT results as well as training and certification of individuals performing POCT. Factors to consider when implementing connectivity between POCT instruments and the electronic medical record are also discussed in detail and include: uni-directional versus bidirectional communication, linking patient demographic information with POCT software, the importance of positive patient identification and considering where to chart POCT results in the electronic medical record.

Procalcitonin for the early prediction of renal parenchymal involvement in children with UTI: preliminary results.

PubMed

Kotoula, Aggeliki; Gardikis, Stefanos; Tsalkidis, Aggelos; Mantadakis, Elpis; Zissimopoulos, Athanassios; Kambouri, Katerina; Deftereos, Savvas; Tripsianis, Gregorios; Manolas, Konstantinos; Chatzimichael, Athanassios; Vaos, George

2009-01-01

In order to establish the most reliable marker for distinguishing urinary tract infections (UTI) with and without renal parenchymal involvement (RPI), we recorded the clinical features and admission leukocyte count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum procalcitonin (PCT) in 57 children (including 43 girls) aged 2-108 months admitted with a first episode of UTI. RPI was evaluated by Tc-99m dimercaptosuccinic acid (DMSA) scintigraphy within 7 days of admission. To establish cut-off points for ESR, CRP, and PCT, we used receiver operating characteristics curves and compared the area under the curve for ESR, CRP, and PCT. Twenty-seven children were diagnosed as having RPI based on positive renal scintigraphy. A body temperature of >38 degrees C, a history of diarrhea, and poor oral intake were more common in patients with RPI. ESR, CRP, and PCT, but not leukocyte count, were significantly higher in patients with RPI (P < 0.001). PCT was more sensitive and specific for the diagnosis of upper versus lower UTI than ESR and CRP. Using a cut-off value of 0.85 ng/ml, PCT had the best performance, with sensitivity, specificity, and positive and negative predictive values of 89%, 97%, 96%, and 91% respectively. Serum PCT is a better marker than ESR, CRP, and leukocyte count for the early prediction of RPI in children with a first episode of UTI.

Renal preservation in children with neurogenic bladder-sphincter dysfunction followed in a national program.

PubMed

Wide, Peter; Glad Mattsson, Gunilla; Mattsson, Sven

2012-04-01

Neurogenic bladder-sphincter dysfunction (NBSD) constitutes the major reason for morbidity in children with spina bifida. The aim of this study was to identify risk factors for renal damage in children with NBSD followed according to the Swedish national guidelines. Records and cystometries from 6 to 16 years (median 11) follow up of 41 consecutive children born 1993-2003 with NBSD were evaluated. The children were divided into a high pressure group (baseline pressure above 30 cmH(2)O at maximal clean intermittent catheterization volume in at least two cystometries) and a low pressure group. Most children (34/41) were followed from birth. Although renal scarring on DMSA-scintigraphy was found in 5/41 children, all but one had normal renal function. Two already had renal scars on entering the follow-up program at age 2.5 and 3 years. Renal scarring was more frequent in the high pressure group (P < 0.01). Most children with renal scars (4/5) had a combination of low compliant bladder and insufficient compliance with treatment and follow up. High baseline pressure is confirmed as a risk factor that, in combination with complex social issues, creates a demanding situation for families and professionals. A structured early follow up with treatment compliance effectively prevents renal damage. Copyright © 2011 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Current limitations and recommendations to improve testing for the environmental assessment of endocrine active substances

EPA Science Inventory

In this paper existing regulatory frameworks and test systems for assessing potential endocrine-active chemicals are described, and associated challenges discussed, along with proposed approaches to address these challenges. Regulatory frameworks vary somewhat across organizatio...

The diagnosis of Brazil nut allergy using history, skin prick tests, serum-specific immunoglobulin E and food challenges.

PubMed

Ridout, S; Matthews, S; Gant, C; Twiselton, R; Dean, T; Arshad, S H

2006-02-01

Allergy to Brazil nut is a relatively common nut allergy and can be fatal. However, the evidence is lacking regarding the best approach to its diagnosis. We sought to determine the relative merits of history, skin prick testing, measurement of serum-specific IgE and challenge in the diagnosis of Brazil nut allergy. Fifty-six children and adults with a history of an allergic reaction to Brazil nut or evidence of sensitization were investigated by questionnaire (n=56), skin prick tests (SPTs) (n=53), measurement of serum-specific IgE to Brazil nut (n=54) and double-blind, placebo-controlled labial, and if necessary oral, challenges (n=19). Brazil nut allergy occurred in highly atopic individuals of any age with a strong family history of atopy. In 24 of 56 (43%), the history of an immediate reaction was sufficient to make a diagnosis with confidence and an oral challenge was considered unsafe. Of the 19 subjects undertaking the 'gold standard' test of a double-blind, placebo-controlled, food challenge, all six subjects with a SPT of at least 6 mm had a positive challenge and all three subjects with a SPT of 0 mm had a negative challenge. In the remaining 10 (53%) subjects, where SPT was between 1 and 5 mm and serum-specific IgE was less than 3.5 kU/L, an oral challenge was performed resulting in three positive and seven negative challenges. A combination of history, SPT and serum-specific IgE was adequate in achieving a diagnosis in the majority (77%) patients with suspected Brazil nut allergy. However, a doubtful history with SPT between 1 and 5 mm, or a serum-specific IgE less than 3.5 kU/L may require an oral challenge to help determine the risk of a Brazil nut allergic reaction.

The space shuttle launch vehicle aerodynamic verification challenges

NASA Technical Reports Server (NTRS)

Wallace, R. O.; Austin, L. D.; Hondros, J. G.; Surber, T. E.; Gaines, L. M.; Hamilton, J. T.

1985-01-01

The Space Shuttle aerodynamics and performance communities were challenged to verify the Space Shuttle vehicle (SSV) aerodynamics and system performance by flight measurements. Historically, launch vehicle flight test programs which faced these same challenges were unmanned instrumented flights of simple aerodynamically shaped vehicles. However, the manned SSV flight test program made these challenges more complex because of the unique aerodynamic configuration powered by the first man-rated solid rocket boosters (SRB). The analyses of flight data did not verify the aerodynamics or performance preflight predictions of the first flight of the Space Transportation System (STS-1). However, these analyses have defined the SSV aerodynamics and verified system performance. The aerodynamics community also was challenged to understand the discrepancy between the wind tunnel and flight defined aerodynamics. The preflight analysis challenges, the aerodynamic extraction challenges, and the postflight analyses challenges which led to the SSV system performance verification and which will lead to the verification of the operational ascent aerodynamics data base are presented.

Bronchial provocation tests in clinical practice.

PubMed

Borges, Marcos de Carvalho; Ferraz, Erica; Vianna, Elcio Oliveira

2011-01-01

Bronchial hyperresponsiveness, which consists of an exaggerated response of the airways to bronchoconstrictor stimuli, is one of the main characteristics of asthma, presented in nearly all asthmatic patients. Bronchial hyperresponsiveness may also be present in other diseases, such as allergic rhinitis, chronic obstructive pulmonary disease, cystic fibrosis, heart failure and respiratory infection, and with some medications, such as β-blockers. Bronchial provocation tests (also known as bronchial challenges) are used to evaluate bronchial responsiveness. These tests have become increasingly used over the last 20 years, with the development and validation of accurate, safe and reproducible tests, and with the publication of well-detailed protocols. Several stimuli can be used in a bronchial challenge, and they are classified as direct and indirect stimuli. There are many indications for a bronchial challenge. In this review, we discuss the main differences between direct and indirect stimuli, and the use of bronchial challenges in clinical practice, especially for confirming diagnoses of asthma, exercise-induced bronchoconstriction and cough-variant asthma, and for use among elite-level athletes.

Sesame allergy: role of specific IgE and skin-prick testing in predicting food challenge results.

PubMed

Permaul, Perdita; Stutius, Lisa M; Sheehan, William J; Rangsithienchai, Pitud; Walter, Jolan E; Twarog, Frank J; Young, Michael C; Scott, Jordan E; Schneider, Lynda C; Phipatanakul, Wanda

2009-01-01

There are conflicting data regarding the diagnostic value of sesame-specific IgE and sesame skin test. Currently, there are no established thresholds that predict clinical reactivity. We examined the correlation of sesame ImmunoCAP and skin-prick test (SPT) results with oral challenge outcomes in children suspected of having a sesame food allergy. We conducted a retrospective chart review of children, aged 2-12 years, receiving a sesame ImmunoCAP level, SPT, and food challenge from January 2004 to August 2008 at Children's Hospital Boston and affiliated allergy clinics. Food challenges were conducted in cases of questionable clinical history or a negative ImmunoCAP and/or negative SPT despite a convincing history. Thirty-three oral sesame challenges were conducted. Of the 33 challenges performed, 21% (n = 7) failed and 79% (n = 26) passed. A sesame-specific IgE level of > or = 7 kU(A)/L showed specificity of >90%. An SPT wheal size of > or = 6 mm showed specificity of >90%. Receiver operator characteristic (ROC) curve analysis for sesame-specific IgE revealed an area under the curve (AUC) of 0.56. ROC curve analysis for SPT wheal size revealed an AUC of 0.67. To our knowledge, this study represents the largest number of sesame challenges performed to evaluate the diagnostic value of both sesame-specific IgE and SPT. Based on our sample, both tests are not good predictors of true sesame allergy as determined by an oral challenge. We were unable to establish a threshold with a 95% positive predictive value for both sesame-specific IgE and SPT.

Patch Test Negative Generalized Dermatitis.

PubMed

Spiker, Alison; Mowad, Christen

2016-01-01

Allergic contact dermatitis is a common condition in dermatology. Patch testing is the criterion standard for diagnosis. However, dermatitis is not always caused by an allergen, and patch testing does not identify a culprit in every patient. Generalized dermatitis, defined as eczematous dermatitis affecting greater than 3 body sites, is often encountered in dermatology practice, especially patch test referral centers. Management for patients with generalized dermatitis who are patch test negative is challenging. The purpose of this article is to outline an approach to this challenging scenario and summarize the paucity of existing literature on patch test negative generalized dermatitis.

Comparison of spike and aerosol challenge tests for the recovery of viable influenza virus from non-woven fabrics.

PubMed

Zuo, Zhili; de Abin, Martha; Chander, Yogesh; Kuehn, Thomas H; Goyal, Sagar M; Pui, David Y H

2013-09-01

To experimentally determine the survival kinetics of influenza virus on personal protective equipment (PPE) and to evaluate the risk of virus transfer from PPE, it is important to compare the effects on virus recovery of the method used to contaminate the PPE with virus and the type of eluent used to recover it. Avian influenza virus (AIV) was applied as a liquid suspension (spike test) and as an aerosol to three types of non-woven fabrics [polypropylene (PP), polyester (PET), and polyamide (Nylon)] that are commonly used in the manufacture of PPE. This was followed by virus recovery using eight different eluents (phosphate-buffered saline, minimum essential medium, and 1.5% or 3.0% beef extract at pH 7, 8, or 9). For spike tests, no statistically significant difference was found in virus recovery using any of the eluents tested. Hydrophobic surfaces (PP and PET) yielded higher spiked virus recovery than hydrophilic Nylon. From all materials, the virus recovery was much lower in aerosol challenge tests than in spike tests. Significant differences were found in the recovery of viable AIV from non-woven fabrics between spike and aerosol challenge tests. The findings of this study demonstrate the need for realistic aerosol challenge tests rather than liquid spike tests in studies of virus survival on surfaces where airborne transmission of influenza virus may get involved. © 2013 John Wiley & Sons Ltd.

sIgE Ana o 1, 2 and 3 accurately distinguish tolerant from allergic children sensitized to cashew nuts.

PubMed

van der Valk, J P M; Gerth van Wijk, R; Vergouwe, Y; Steyerberg, E W; Reitsma, M; Wichers, H J; Savelkoul, H F J; Vlieg-Boerstra, B; de Groot, H; Dubois, A E J; de Jong, N W

2017-01-01

The double-blind, placebo-controlled food challenge test (DBPCFC) is the gold standard in cashew nut allergy. This test is costly, time consuming and not without side effects. Analysis of IgE reactivity to cashew nut components may reduce the need for food challenge tests. In a prospective and multicentre study, children with suspected cashew nut allergy underwent a DBPCFC with cashew nut. Specific IgE to cashew nut and to the components Ana o 1, 2 and 3 were determined. A skin prick test (SPT) with cashew nut extract was performed. The association between the outcome of the food challenge test and specific IgE to Ana o 1, 2 and 3 was assessed with logistic regression analyses, unadjusted and adjusted for other diagnostic variables. Discriminative ability was quantified with a concordance index (c). A total of 173 children (103 boys, 60%) with a median age of 9 years were included. About 79% had a positive challenge test outcome. A steep rise in the risk of a positive challenge was observed for specific IgE to each individual component Ana o 1, 2 and 3 with estimated risks up to approximately 100%. Median values of Ana o 1, 2, 3 were 1.29 kU/l (range 0-100 kU/l), 4.77 kU/l (range 0-100 kU/l) and 8.33 kU/l (range 0-100 kU/l) respectively and varied significantly (p < 0.001). Specific IgE to Ana o 1, 2 and 3 was better distinguished between cashew-allergic and tolerant children (c = 0.87, 0.85 and 0.89, respectively) than specific IgE to cashew nut or SPT (c = 0.76 and 0.83, respectively). The major cashew nut allergens Ana o 1, 2 and 3 are each individually predictive for the outcome of food challenge tests in cashew-allergic children. © 2016 John Wiley & Sons Ltd.

Modeling and design of challenge tests: Inflammatory and metabolic biomarker study examples.

PubMed

Gabrielsson, Johan; Hjorth, Stephan; Vogg, Barbara; Harlfinger, Stephanie; Gutierrez, Pablo Morentin; Peletier, Lambertus; Pehrson, Rikard; Davidsson, Pia

2015-01-25

Given the complexity of pharmacological challenge experiments, it is perhaps not surprising that design and analysis, and in turn interpretation and communication of results from a quantitative point of view, is often suboptimal. Here we report an inventory of common designs sampled from anti-inflammatory, respiratory and metabolic disease drug discovery studies, all of which are based on animal models of disease involving pharmacological and/or patho/physiological interaction challenges. The corresponding data are modeled and analyzed quantitatively, the merits of the respective approach discussed and inferences made with respect to future design improvements. Although our analysis is limited to these disease model examples, the challenge approach is generally applicable to the vast majority of pharmacological intervention studies. In the present five Case Studies results from pharmacodynamic effect models from different therapeutic areas were explored and analyzed according to five typical designs. Plasma exposures of test compounds were assayed by either liquid chromatography/mass spectrometry or ligand binding assays. To describe how drug intervention can regulate diverse processes, turnover models of test compound-challenger interaction, transduction processes, and biophase time courses were applied for biomarker response in eosinophil count, IL6 response, paw-swelling, TNFα response and glucose turnover in vivo. Case Study 1 shows results from intratracheal administration of Sephadex, which is a glucocorticoid-sensitive model of airway inflammation in rats. Eosinophils in bronchoalveolar fluid were obtained at different time points via destructive sampling and then regressed by the mixed-effects modeling. A biophase function of the Sephadex time course was inferred from the modeled eosinophil time courses. In Case Study 2, a mouse model showed that the time course of cytokine-induced IL1β challenge was altered with or without drug intervention. Anakinra reversed the IL1β induced cytokine IL6 response in a dose-dependent manner. This Case Study contained time courses of test compound (drug), challenger (IL1β) and cytokine response (IL6), which resulted in high parameter precision. Case Study 3 illustrates collagen-induced arthritis progression in the rat. Swelling scores (based on severity of hind paw swelling) were used to describe arthritis progression after the challenge and the inhibitory effect of two doses of an orally administered test compound. In Case Study 4, a cynomolgus monkey model for lipopolysaccharide LPS-induced TNFα synthesis and/or release was investigated. This model provides integrated information on pharmacokinetics and in vivo potency of the test compounds. Case Study 5 contains data from an oral glucose tolerance test in rats, where the challenger is the same as the pharmacodynamic response biomarker (glucose). It is therefore convenient to model the extra input of glucose simultaneously with baseline data and during intervention of a glucose-lowering compound at different dose levels. Typically time-series analyses of challenger- and biomarker-time data are necessary if an accurate and precise estimate of the pharmacodynamic properties of a test compound is sought. Erosion of data, resulting in the single-point assessment of drug action after a challenge test, should generally be avoided. This is particularly relevant for situations where one expects time-curve shifts, tolerance/rebound, impact of disease, or hormetic concentration-response relationships to occur. Copyright © 2014 Elsevier B.V. All rights reserved.

The Challenge Course Experience Questionnaire: A Facilitator's Assessment Tool

ERIC Educational Resources Information Center

Schary, David P.; Waldron, Alexis L.

2017-01-01

Challenge course programs influence a variety of psychological, social, and educational outcomes. Yet, many challenges exist when measuring challenge course outcomes like logistical constraints and a lack of specific assessment tools. This study piloted and tested an assessment tool designed for facilitators to measure participant outcomes in…

Expressive communication of children with autism: the use of challenging behaviour.

PubMed

Chiang, Hsu-Min

2008-11-01

There is a lack of empirical research investigating challenging behaviour in children with autism with severe speech impairments in naturalistic settings. The aim of the present study was to investigate challenging behaviour among Australian and Taiwanese children with autism who are non-verbal or have limited speech (i.e. less than five functional words) in school settings and to address the following questions: (1) What are the communicative characteristics (e.g. communicative functions, partners, activities and partner's responses) of challenging behaviour? (2) Do sample characteristics (e.g. age, severity of autism, adaptive behaviour level, the use of graphic symbols, the use of non-symbolic acts, the use of speech) associate with the amount of challenging behaviour? (3) Do cultural differences exist in communicative variables of challenging behaviour? Naturalistic observations were used to investigate challenging behaviour in children with autism. A total of 32 (17 Australian and 15 Taiwanese) children with autism who were non-verbal or had limited speech participated in the current study and each participant was videotaped for 2 h during his/her everyday school routines. Sixteen out of 32 children had challenging behaviour. Challenging behaviour was used for requesting and rejecting communicative functions. A paired-samples t-test revealed that no significant differences existed in the frequency of occurrence between request and reject. Challenging behaviour was directed to adults and peers. A paired-samples t-test revealed that challenging behaviour was directed to adults significantly more frequently than to peers. Communicative partners showed different responses (e.g. deny, no response, delivered, removed, acknowledge) to challenging behaviour. A repeated-measures analysis of variance (ANOVA) revealed a main effect for partner response. Deny was the most common response. Challenging behaviour occurred across a variety of classroom activities (e.g. academic activities, morning circle, morning tea, lunch, free time). A repeated-measures ANOVA revealed a main effect for activity. Challenging behaviour occurred most often during academic activities. A set of correlation analyses indicated a significant correlation existed between the use of graphic symbols and the amount of challenging behaviour. A series of Mann-Whitney U-tests revealed significant differences between Australian and Taiwanese children on the amount of challenging behaviour, communicative functions and partners. A Chi-squared test revealed that there were significantly more Australian children with autism who displayed challenging behaviour than Taiwanese children. The current study shows that a high proportion of children with autism with severe speech impairments used challenging behaviour as a form of expressive communication in their school environments. The findings from the present study may have implications for practitioners who work with children with autism.

D3R grand challenge 2015: Evaluation of protein-ligand pose and affinity predictions

NASA Astrophysics Data System (ADS)

Gathiaka, Symon; Liu, Shuai; Chiu, Michael; Yang, Huanwang; Stuckey, Jeanne A.; Kang, You Na; Delproposto, Jim; Kubish, Ginger; Dunbar, James B.; Carlson, Heather A.; Burley, Stephen K.; Walters, W. Patrick; Amaro, Rommie E.; Feher, Victoria A.; Gilson, Michael K.

2016-09-01

The Drug Design Data Resource (D3R) ran Grand Challenge 2015 between September 2015 and February 2016. Two targets served as the framework to test community docking and scoring methods: (1) HSP90, donated by AbbVie and the Community Structure Activity Resource (CSAR), and (2) MAP4K4, donated by Genentech. The challenges for both target datasets were conducted in two stages, with the first stage testing pose predictions and the capacity to rank compounds by affinity with minimal structural data; and the second stage testing methods for ranking compounds with knowledge of at least a subset of the ligand-protein poses. An additional sub-challenge provided small groups of chemically similar HSP90 compounds amenable to alchemical calculations of relative binding free energy. Unlike previous blinded Challenges, we did not provide cognate receptors or receptors prepared with hydrogens and likewise did not require a specified crystal structure to be used for pose or affinity prediction in Stage 1. Given the freedom to select from over 200 crystal structures of HSP90 in the PDB, participants employed workflows that tested not only core docking and scoring technologies, but also methods for addressing water-mediated ligand-protein interactions, binding pocket flexibility, and the optimal selection of protein structures for use in docking calculations. Nearly 40 participating groups submitted over 350 prediction sets for Grand Challenge 2015. This overview describes the datasets and the organization of the challenge components, summarizes the results across all submitted predictions, and considers broad conclusions that may be drawn from this collaborative community endeavor.

D3R Grand Challenge 2015: Evaluation of Protein-Ligand Pose and Affinity Predictions

PubMed Central

Gathiaka, Symon; Liu, Shuai; Chiu, Michael; Yang, Huanwang; Stuckey, Jeanne A; Kang, You Na; Delproposto, Jim; Kubish, Ginger; Dunbar, James B.; Carlson, Heather A.; Burley, Stephen K.; Walters, W. Patrick; Amaro, Rommie E.; Feher, Victoria A.; Gilson, Michael K.

2017-01-01

The Drug Design Data Resource (D3R) ran Grand Challenge 2015 between September 2015 and February 2016. Two targets served as the framework to test community docking and scoring methods: (i) HSP90, donated by AbbVie and the Community Structure Activity Resource (CSAR), and (ii) MAP4K4, donated by Genentech. The challenges for both target datasets were conducted in two stages, with the first stage testing pose predictions and the capacity to rank compounds by affinity with minimal structural data; and the second stage testing methods for ranking compounds with knowledge of at least a subset of the ligand-protein poses. An additional sub-challenge provided small groups of chemically similar HSP90 compounds amenable to alchemical calculations of relative binding free energy. Unlike previous blinded Challenges, we did not provide cognate receptors or receptors prepared with hydrogens and likewise did not require a specified crystal structure to be used for pose or affinity prediction in Stage 1. Given the freedom to select from over 200 crystal structures of HSP90 in the PDB, participants employed workflows that tested not only core docking and scoring technologies, but also methods for addressing water-mediated ligand-protein interactions, binding pocket flexibility, and the optimal selection of protein structures for use in docking calculations. Nearly 40 participating groups submitted over 350 prediction sets for Grand Challenge 2015. This overview describes the datasets and the organization of the challenge components, summarizes the results across all submitted predictions, and considers broad conclusions that may be drawn from this collaborative community endeavor. PMID:27696240

In vitro Alternative Methodologies for Central Nervous System Assessment: A Critique using Nanoscale Materials as an Example.

EPA Science Inventory

Identifying the potential health hazards to the central nervous system of a new family of materials presents many challenges. Whole-animal toxicity testing has been the tradition, but in vitro methods have been steadily gaining popularity. There are numerous challenges in testing...

Radiation Testing, Characterization and Qualification Challenges for Modern Microelectronics and Photonics Devices and Technologies

NASA Technical Reports Server (NTRS)

LaBel, Kenneth A.; Cohn, Lewis M.

2008-01-01

At an earlier conference we discussed a selection of the challenges for radiation testing of modern semiconductor devices focusing on state-of-the-art CMOS technologies. In this presentation, we extend this discussion focusing on the following areas: (1) Device packaging, (2) Evolving physical single even upset mechanisms, (3) Device complexity, and (4) the goal of understanding the limitations and interpretation of radiation testing results.

Validation of the cephalosporin intradermal skin test for predicting immediate hypersensitivity: a prospective study with drug challenge.

PubMed

Yoon, S-Y; Park, S Y; Kim, S; Lee, T; Lee, Y S; Kwon, H-S; Cho, Y S; Moon, H-B; Kim, T-B

2013-07-01

Cephalosporin is a major offending agent in terms of drug hypersensitivity along with penicillin. Cephalosporin intradermal skin tests (IDTs) have been widely used; however, their validity for predicting immediate hypersensitivity has not been studied. This study aimed to determine the predictive value of cephalosporin intradermal skin testing before administration of the drug. We prospectively conducted IDTs with four cephalosporins, one each of selected first-, second-, third-, or fourth-generation cephalosporins: ceftezol; cefotetan or cefamandole; ceftriaxone or cefotaxime; and flomoxef, respectively, as well as with penicillin G. After the skin test, whatever the result, one of the tested cephalosporins was administered intravenously and the patient was carefully observed. We recruited 1421 patients who required preoperative cephalosporins. Seventy-four patients (74/1421, 5.2%) were positive to at least one cephalosporin. However, none of responders had immediate hypersensitivity reactions after a challenge dose of the same or different cephalosporin, which were positive in the skin test. Four patients who suffered generalized urticaria and itching after challenge gave negative skin tests for the corresponding drug. The IDT for cephalosporin had a sensitivity of 0%, a specificity of 97.5%, a negative predictive value of 99.7%, and a positive predictive value (PPV) of 0%, when challenged with the same drugs that were positive in the skin test. Routine skin testing with a cephalosporin before its administration is not useful for predicting immediate hypersensitivity because of the extremely low sensitivity and PPV of the skin test (CRIS registration no. KCT0000455). © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Challenges of Cold Conditioning and Static Testing the Second Ares Demonstration Motor (DM-2)

NASA Technical Reports Server (NTRS)

Quinn, Shyla; Davis, Larry C.

2011-01-01

On August 31, 2010, a five-segment demonstration motor (DM) for the Ares program was successfully tested. A series of demonstration motors (DMs) will be tested in different conditioned environments to confirm they meet their design specifications. The second demonstration motor (DM-2) was the first cold motor. The motor needed to be subjected to sub-freezing temperatures for two months so that its internal propellant mean bulk temperature (PMBT) was approximately 40 F. Several challenges had to be overcome to make this a successful test. One challenge was to condition four field joints to get the O-rings approximately 32 F. This would be done by applying conditioning shrouds to externally cool each field joint after the test bay was pulled off. The purpose of this conditioning was to validate the new O-ring design and allow joint heaters to be eliminated. Another challenge was maintaining temperature requirements for components in the nozzle vectoring system. A separate heating system was used to warm these components during cold conditioning. There were 53 test objectives that required 764 channels of data to be recorded; 460 were specific to DM-2. This instrumentation had to be installed prior to conditioning, which meant the baseline process and timeline had to be modified to meet this time critical schedule.

Emerging Resistance, New Antimicrobial Agents  …  but No Tests! The Challenge of Antimicrobial Susceptibility Testing in the Current US Regulatory Landscape.

PubMed

Humphries, R M; Hindler, J A

2016-07-01

Accurate and timely performance of antimicrobial susceptibility testing (AST) by the clinical laboratory is paramount to combating antimicrobial resistance. The ability of laboratories in the United States to effectively perform ASTs is challenged by several factors. Some, such as new resistance mechanisms and the associated evolution of testing recommendations and breakpoints, are inevitable. Others are entirely man-made. These include unnecessarily strict US Food and Drug Administration (FDA) limitations on how commercial AST systems can be used for diagnostic testing, the absence of up-to-date performance data on these systems, and the lack of commercially available FDA-cleared tests for newer antimicrobial agents or for older agents with updated breakpoints. This viewpoint will highlight contemporary AST challenges faced by the clinical laboratory, and propose some solutions. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Challenges to Integrating Pharmacogenetic Testing into Medication Therapy Management

PubMed Central

Allen LaPointe, Nancy M.; Moaddeb, Jivan

2015-01-01

Background Some have proposed the integration of pharmacogenetic (PGx) testing into medication therapy management (MTM) to enable further refinement of treatment(s) to reduce risk of adverse responses and improve efficacy. PGx testing involves the analysis of genetic variants associated with therapeutic or adverse response and may be useful in enhancing the ability to identify ineffective and/or harmful drugs or drug combinations. This “enhanced” MTM might also reduce patient concerns about side effects and increase confidence that the medication is effective, addressing two key factors that impact patient adherence - concern and necessity. However, the feasibility and effectiveness of the integration of PGx testing into MTM in clinical practice has not yet been determined. Objectives In this paper, we consider some of the challenges to the integration and delivery of PGx testing in MTM services. What is already known about this subject While the addition of pharmacogenetic testing has been suggested, little literature exists exploring the challenges or feasibility of doing so. PMID:25803768

Aerodynamic challenges of ALT

NASA Technical Reports Server (NTRS)

Hooks, I.; Homan, D.; Romere, P. O.

1985-01-01

The approach and landing test (ALT) of the Space Shuttle Orbiter presented a number of unique challenges in the area of aerodynamics. The purpose of the ALT program was both to confirm the use of the Boeing 747 as a transport vehicle for ferrying the Orbiter across the country and to demonstrate the flight characteristics of the Orbiter in its approach and landing phase. Concerns for structural fatigue and performance dictated a tailcone be attached to the Orbiter for ferry and for the initial landing tests. The Orbiter with a tailcone attached presented additional challenges to the normal aft sting concept of wind tunnel testing. The landing tests required that the Orbiter be separated from the 747 at approximately 20,000 feet using aerodynamic forces to fly the vehicles apart. The concept required a complex test program to determine the relative effects of the two vehicles on each other. Also of concern, and tested, was the vortex wake created by the 747 and the means for the Orbiter to avoid it following separation.

Validation of novel recipes for double-blind, placebo-controlled food challenges in children and adults.

PubMed

Vlieg-Boerstra, B J; Herpertz, I; Pasker, L; van der Heide, S; Kukler, J; Jansink, C; Vaessen, W; Beusekamp, B J; Dubois, A E J

2011-07-01

In double-blind, placebo-controlled food challenges (DBPCFCs), the use of challenge materials in which blinding is validated is a prerequisite for obtaining true blinded conditions during the test procedure. Therefore, the aim of this study was to enlarge the available range of validated recipes for DBPCFCs to facilitate oral challenge tests in all age groups, including young children, while maximizing the top dose in an acceptable volume. Recipes were developed and subsequently validated by a panel recruited by a matching sensory test. The best 30% of candidates were selected to participate in sensory testing using the paired comparison test. For young children, three recipes with cow's milk and one recipe with peanut could be validated which may be utilized in DBPCFCs. For children older than 4 years and adults, one recipe with egg, two with peanut, one with hazelnut, and one with cashew nut were validated for use in DBPCFCs. All recipes contained larger amounts of allergenic foods than previously validated. These recipes increase the range of validated recipes for use in DBPCFCs in adults and children. © 2011 John Wiley & Sons A/S.

Expanding Access to Malaria Diagnosis through Retail Shops in Western Kenya: What Do Shop Workers Think?

PubMed

Rusk, Andria; Goodman, Catherine; Naanyu, Violet; Koech, Beatrice; Obala, Andrew; O'Meara, Wendy Prudhomme

2013-01-01

Background. The common symptoms of malaria reduce the specificity of clinical diagnosis. Presumptive treatment is conventional but can lead to overdiagnosis of malaria, delay of appropriate treatment, overprescription of antimalarials, and drug resistance. Routine use of diagnostic tests can address many of these concerns. Though treatment is often procured from retailers, there is low availability of rapid diagnostic tests for malaria (MRDTs), a simple, inexpensive, and accurate diagnostic solution. We know little about the challenges to expanding access to diagnostics through these outlets. Methods. To understand the perceptions of the benefits and challenges to selling rapid diagnostic tests for malaria, we conducted focus group discussions with antimalarial retailers who serve the residents of the Webuye Health and Demographic Surveillance Site in western Kenya. Results. Medicine retailers perceived MRDTs to be beneficial to their customers and businesses but also included cost, fear of the tests, risks of self-treatment, and regulatory concerns among the challenges to using and selling MRDTs. Conclusion. MRDTs represent a viable approach to increase access to malaria diagnostic testing. Medicine retailers are eager for MRDTs to be made available to them. However, certain challenges remain to implementation in retail outlets and should be addressed in advance.

Nonclinical safety testing of biopharmaceuticals--Addressing current challenges of these novel and emerging therapies.

PubMed

Brennan, Frank R; Baumann, Andreas; Blaich, Guenter; de Haan, Lolke; Fagg, Rajni; Kiessling, Andrea; Kronenberg, Sven; Locher, Mathias; Milton, Mark; Tibbitts, Jay; Ulrich, Peter; Weir, Lucinda

2015-10-01

Non-clinical safety testing of biopharmaceuticals can present significant challenges to human risk assessment with these often innovative and complex drugs. Hot Topics in this field were discussed recently at the 4th Annual European Biosafe General Membership meeting. In this feature article, the presentations and subsequent discussions from the main sessions are summarized. The topics covered include: (i) wanted versus unwanted immune activation, (ii) bi-specific protein scaffolds, (iii) use of Pharmacokinetic (PK)/Pharmacodynamic (PD) data to impact/optimize toxicology study design, (iv) cytokine release and challenges to human translation (v) safety testing of cell and gene therapies including chimeric antigen receptor T (CAR-T) cells and retroviral vectors and (vi) biopharmaceutical development strategies encompassing a range of diverse topics including optimizing entry of monoclonal antibodies (mAbs) into the brain, safety testing of therapeutic vaccines, non-clinical testing of biosimilars, infection in toxicology studies with immunomodulators and challenges to human risk assessment, maternal and infant anti-drug antibody (ADA) development and impact in non-human primate (NHP) developmental toxicity studies, and a summary of an NC3Rs workshop on the future vision for non-clinical safety assessment of biopharmaceuticals. Copyright © 2015 Elsevier Inc. All rights reserved.

The after breakfast 50-g, 1-hour glucose challenge test in urban Mexican pregnant women: its sensitivity and specificity evaluated by three diagnostic criteria for gestational diabetes mellitus.

PubMed

Espinosa de los Monteros, A; Parra, A; Hidalgo, R; Zambrana, M

1999-04-01

To study the sensitivity and specificity of the 50-g, 1-hour gestational glucose challenge test performed 1 to 2 hours after a non-standardized home breakfast in urban Mexican women by using three different gestational diabetes mellitus diagnostic criteria. Four hundred and forty-five consecutive women of 24-28 weeks gestation were studied. The glucose challenge test was performed in the fed state and a week later a fasting 100-g, 3-hours oral glucose tolerance test was carried out in all of them. Duplicate serum glucose concentrations were determined by a glucose-oxidase method. Sensitivity and specificity were calculated using three different diagnostic criteria for gestational diabetes mellitus. The glucose challenge test performed as indicated, with a cutoff of 7.8 mmol/L, had 88-89% sensitivity and 85-87% specificity when using as diagnostic criteria those proposed by the National Diabetes Data Group and by Carpenter & Coustan; by using Sacks et al. criteria, the values were 82% and 88%, respectively. Considering only pregnant women > or = 25 years of age, the sensitivity increased to 92% with the National Diabetes Data Group criteria. Pregnant women < 25 years of age had significantly lower blood glucose values than those with age > or = 25 years during the glucose tolerance test. For the general group the sensitivity of the glucose challenge test performed 1 to 2 hours after breakfast was similar, based on the National Diabetes Data Group and the Carpenter & Coustan's diagnostic criteria for gestational diabetes mellitus. However, when pregnant women > or = 25 years of age were considered, the use of the former criteria yielded a slightly better sensitivity.

The predictive value of specific immunoglobulin E levels in serum for the outcome of the development of tolerance in cow's milk allergy.

PubMed

Martorell, A; García Ara, M C; Plaza, A M; Boné, J; Nevot, S; Echeverria, L; Alonso, E; Garde, J

2008-01-01

Immunoglobulin E-mediated allergy to cow's milk protein (CMP) tends to subside over years of follow-up. The gold standard for detecting such allergy has been the oral challenge test. The development of some other test for determining the correct timing of the oral challenge test would avoid unnecessary patient discomfort. The aim of this study was to determine whether monitoring cow's milk (CM) specific IgE levels over time can be used as a predictor for determining when patients develop clinical tolerance. A prospective 4-year follow-up study was made of 170 patients with IgE-mediated allergy to CMP, involving periodic evaluations (12, 18, 24, 36 and 48 months) with the determination of casein and CM specific IgE on each visit, along with CM challenge testing. ROC curves were used to analyse the sensitivity, specificity and predictive values of the casein and CM specific IgE levels versus the challenge test outcomes at the different moments of follow-up. In the course of follow-up, 140 infants (82 %) became tolerant. Specific IgE levels to CM: 2.58, 2.5, 2.7, 2.26, 5 kU(A)/l and to casein: 0.97, 1.22, 3, 2.39, 2.73 kU(A)/l, respectively, predicted clinical reactivity (greatest diagnostic efficiency values) at the different analysed moments of follow-up (12, 18, 24, 36 and 48 months). Quantification of CMP specific IgE is a useful test for diagnosing symptomatic allergy to CM in the paediatric population, and could eliminate the need to perform oral challenges tests in a significant number of children.

Mud crab susceptibility to disease from white spot syndrome virus is species-dependent.

PubMed

Somboonna, Naraporn; Mangkalanan, Seksan; Udompetcharaporn, Attasit; Krittanai, Chartchai; Sritunyalucksana, Kallaya; Flegel, Tw

2010-11-20

Based on a report for one species (Scylla serrata), it is widely believed that mud crabs are relatively resistant to disease caused by white spot syndrome virus (WSSV). We tested this hypothesis by determining the degree of susceptibility in two species of mud crabs, Scylla olivacea and Scylla paramamosain, both of which were identified by mitochondrial 16 S ribosomal gene analysis. We compared single-dose and serial-dose WSSV challenges on S. olivacea and S. paramamosain. In a preliminary test using S. olivacea alone, a dose of 1 × 106 WSSV copies/g gave 100% mortality within 7 days. In a subsequent test, 17 S. olivacea and 13 S. paramamosain were divided into test and control groups for challenge with WSSV at 5 incremental, biweekly doses starting from 1 × 104 and ending at 5 × 106 copies/g. For 11 S. olivacea challenged, 3 specimens died at doses between 1 × 105 and 5 × 105 copies/g and none died for 2 weeks after the subsequent dose (1 × 106 copies/g) that was lethal within 7 days in the preliminary test. However, after the final challenge on day 56 (5 × 106 copies/g), the remaining 7 of 11 S. olivacea (63.64%) died within 2 weeks. There was no mortality in the buffer-injected control crabs. For 9 S. paramamosain challenged in the same way, 5 (55.56%) died after challenge doses between 1 × 104 and 5 × 105 copies/g, and none died for 2 weeks after the challenge dose of 1 × 106 copies/g. After the final challenge (5 × 106 copies/g) on day 56, no S. paramamosain died during 2 weeks after the challenge, and 2 of 9 WSSV-infected S. paramamosain (22.22%) remained alive together with the control crabs until the end of the test on day 106. Viral loads in these survivors were low when compared to those in the moribund crabs. S. olivacea and S. paramamosain show wide variation in response to challenge with WSSV. S. olivacea and S. paramamosain are susceptible to white spot disease, and S. olivacea is more susceptible than S. paramamosain. Based on our single-challenge and serial challenge results, and on previous published work showing that S. serrata is relatively unaffected by WSSV infection, we propose that susceptibility to white spot disease in the genus Scylla is species-dependent and may also be dose-history dependent. In practical terms for shrimp farmers, it means that S. olivacea and S. paramamosain may pose less threat as WSSV carriers than S. serrata. For crab farmers, our results suggest that rearing of S. serrata would be a better choice than S. paramamosain or S. olivacea in terms of avoiding losses from seasonal outbreaks of white spot disease.

Diagnostic accuracy of patch test in children with food allergy.

PubMed

Caglayan Sozmen, Sule; Povesi Dascola, Carlotta; Gioia, Edoardo; Mastrorilli, Carla; Rizzuti, Laura; Caffarelli, Carlo

2015-08-01

The gold standard test for confirming whether a child has clinical hypersensitivity reactions to foods is the oral food challenge. Therefore, there is increasing interest in simpler diagnostic markers of food allergy, especially in children, to avoid oral food challenge. The goal of this study was to assess the diagnostic accuracy of atopy patch test in comparison with oral food challenge. We investigated 243 children (mean age, 51 months) referred for evaluation of suspected egg or cow's milk allergy. Skin prick test and atopy patch test were carried out, and after a 2 weeks elimination diet, oral food challenge was performed. Two hundred and forty-three children underwent OFC to the suspected food. We found clinically relevant food allergies in 40 (65%) children to egg and in 22 (35%) to cow's milk. The sensitivity of skin prick test for both milk and egg was 92%, specificity 91%, positive predictive value 35%, and negative predictive value of 93%. Sensitivity, specificity, positive predictive value, and negative predictive value of atopy patch test for both milk and egg were 21%, 73%, 20%, and 74%, respectively. Our study suggests that there is insufficient evidence for the routine use of atopy patch test for the evaluation of egg and cow's milk allergy. OFC remains gold standard for the diagnosis of egg and milk allergy even in the presence of high costs in terms of both time and risks during application. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Symptoms, Diagnosis, and Treatment of Cow's Milk Allergy.

PubMed

Vandenplas, Yvan; Marchand, Johan; Meyns, Lien

2015-01-01

The diagnosis and management of cow's milk allergy (CMA) is a topic of debate because there are no specific symptoms and reliable diagnostic tests. Literature was searched using databases to find original papers and reviews on this topic. A "challenge test" is still recommended as the most specific and sensitive diagnostic test, although a positive challenge test does not proof the involvement of the immune system. Only in the rare case of anaphylaxis, the challenge tests is not recommended. The Cow's Milk Symptom Score (CoMiSS) is an awareness tool for health care professionals to better recognize symptoms caused by the ingestion of cow's milk, but still needs validation. Today, the recommended diagnostic approach consists of an elimination diet with an extensive cow's milk based hydrolysate, followed by a challenge test. Amino acid based formula is reserved for the severe cases. Rice hydrolysates are gaining popularity, because they have been shown to be effective, have a better acceptability, and to be cheaper than the extensive cow's milk based hydrolysates. Soy infant formula may offer an additional alternative option as reviews concluded that about 10-15% of infants allergic to cow's milk will also react to soy. Gastro-intestinal microbiota manipulation may be of additional benefit in the treatment of CMA. The development of rice hydrolysates challenge the use of Today, extensive cow's milk based extensive hydrolysates remain the first option for the majority of patients and amino acid formula for the most severe cases. Rice hydrolysates and soy infant formula are considered as second choice options.

Occupational asthma due to turpentine in art painter--case report.

PubMed

Dudek, Wojciech; Wittczak, Tomasz; Swierczyńska-Machura, Dominika; Walusiak-Skorupa, Jolanta; Pałczyński, Cezary

2009-01-01

Turpentine is a fluid obtained by distillation of wood resins containing mixture of terpens. It can act as an irritant and sensitiser. Most common health problem among workers exposed to turpentine is contact dermatitis. Little is know about turpentine to cause type I hypersensitivity reaction. We present a case of a 27-year old art painter using turpentine as a thinner for oil-based paints. She developed asthmatic reactions after 5 years of working with turpentine. A number of clinical procedures were performed, including clinical examination, routine laboratory tests, total serum IgE, skin prick tests to common aeroallergens, metal salts, oil-based paints and balsamic turpentine, resting spirometry test, histamine challenge, and a single-blind, placebo-controlled specific inhalation challenge with balsamic turpentine. Clinical findings and laboratory test results were normal but a significant bronchial hyperreactivity was found. During the specific challenge, dyspnoea and decreased forced expiratory volume (FEV1) were observed in late phase of asthmatic reaction. An increased proportion of eosinophils in induced sputum could also be noted 24 h after the challenge. Positive clinical response to the specific challenge as well as the morphological changes found in induced sputum served as the basis for diagnosing occupational asthma. To our knowledge, this is the first well-documented case of turpentine-induced occupational asthma.

Approach to evaluation and management of a patient with multiple food allergies.

PubMed

Bird, J Andrew

2016-01-01

Diagnosing food allergy is often challenging, and validated testing modalities are mostly limited to immunoglobulin E (IgE)-mediated reactions to foods. Use of food-specific IgE tests and skin prick tests in individuals without a history that supports an IgE-mediated reaction to the specific food being tested diminishes the predictive capabilities of the test. To review the literature regarding evaluation of patients with a concern for multiple food allergies and to demonstrate an evidence-based approach to diagnosis and management. A literature search was performed and articles identified as relevant based on the search terms "food allergy," "food allergy diagnosis," "skin prick test," "serum IgE test," "oral food challenge", and "food allergy management." Patients at risk of food allergy are often misdiagnosed and appropriate evaluation of patients with concern for food allergy includes taking a thorough diet history and reaction history, performing specific tests intentionally and when indicated, and conducting an oral food challenge in a safe environment by an experienced provider when test results are inconclusive. An evidence-based approach to diagnosing and managing a patient at risk of having a life-threatening food allergy is reviewed.

Decision making about healthcare-related tests and diagnostic test strategies. Paper 2: a review of methodological and practical challenges.

PubMed

Mustafa, Reem A; Wiercioch, Wojtek; Cheung, Adrienne; Prediger, Barbara; Brozek, Jan; Bossuyt, Patrick; Garg, Amit X; Lelgemann, Monika; Büehler, Diedrich; Schünemann, Holger J

2017-12-01

In this first of a series of five articles, we provide an overview of how and why healthcare-related tests and diagnostic strategies are currently applied. We also describe how our findings can be integrated with existing frameworks for making decisions that guide the use of healthcare-related tests and diagnostic strategies. We searched MEDLINE, references of identified articles, chapters in relevant textbooks, and identified articles citing classic literature on this topic. We provide updated frameworks for the potential roles and applications of tests with suggested definitions and practical examples. We also discuss study designs that are commonly used to assess tests' performance and the effects of tests on people's health. These designs include diagnostic randomized controlled trials and retrospective validation. We describe the utility of these and other currently suggested designs, which questions they can answer and which ones they cannot. In addition, we summarize the challenges unique to decision-making resulting from the use of tests. This overview highlights current challenges in the application of tests in decision-making in healthcare, provides clarifications, and informs the proposed solutions. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparison of diagnostic validity of mannitol and methacholine challenges and relationship to clinical status and airway inflammation in steroid-naïve asthmatic patients.

PubMed

Porpodis, Konstantinos; Domvri, Kalliopi; Kontakiotis, Theodoros; Fouka, Evangelia; Kontakioti, Eirini; Zarogoulidis, Konstantinos; Papakosta, Despina

2017-06-01

The purpose of this study was to demonstrate and compare the diagnostic validity of two bronchial challenges and to investigate their correlation with patient clinical status, atopy and inflammation markers. Eighty-eight patients, 47 women and 41 men, mean age 38.56 ± 16.73 years who presented with asthma related symptoms and were not on any anti-asthma medication, were challenged with mannitol and methacholine on separate days. Medical history regarding asthmatic symptoms, physical examination, skin prick tests and FeNO levels were also assessed. The clinical diagnosis of asthma was based on bronchodilator reversibility test. Sixty-seven patients were diagnosed with asthma and 21 without asthma. Both methacholine (P < 0.014) and mannitol (P < 0.000) challenges were significant in diagnosing asthma. The positive/negative predictive value was 93.33%/41.86% for methacholine, 97.72%/45.45% for mannitol and 97.05%/45.45%. for both methods assessed together. Worthy of note that 22% of asthmatics had both tests negative. There was a negative correlation between PC20 of methacholine and the FeNO level P < 0.001, and positive with the PD15 of mannitol P < 0.001 and the pre-test FEV 1 % pred P < 0.005, whereas PD15 of mannitol was negatively correlated with the FeNO level P < 0.001. Furthermore, dyspnea was the only asthmatic symptom associated with FeNO level P < 0.035 and the positivity of mannitol P < 0.014 and methacholine P < 0.04. Both challenge tests were equivalent in diagnosing asthma. Nevertheless, specificity appeared to be slightly higher in mannitol challenge.

Acanthamoeba: An Overview of the Challenges to the Development of a Consensus Methodology of Disinfection Efficacy Testing for Contact Lens Care Products.

PubMed

Brocious, Jeffrey; Tarver, Michelle E; Hampton, Denise; Eydelman, Malvina

2018-04-24

With the increasing incidence of more pathogens that can cause microbial keratitis (MK), it is necessary to periodically reassess disinfection multipurpose solutions testing requirements to ensure that relevant organisms to challenge them are being used. Current testing protocols have included common pathogens such as Pseudomonas aeruginosa, Staphylococcus aureus, Serratia marcescens, Candida albicans, and Fusarium solani but have omitted less common pathogens such as Acanthamoeba. Specifically, Acanthamoeba sp. has recently been identified as a prevalent cause of MK in certain countries. Developing an appropriate protocol for this unique organism presents a challenge, given its two distinct life stages, methods to grow the organism, encystment techniques, and many other parameters that can affect testing outcomes. Therefore, the appropriate combination of these parameters is crucial to developing a protocol that ensures consistent, accurate results. The FDA has recognized the importance of establishing a standardized testing protocol for this pathogen and embarked on research efforts to provide a recommended testing protocol for testing contact lens care products.

In vivo screening of candidate pretreatment compounds against cyanide using mice

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

Kiser, R.C.; Olson, C.T.; Menton, R.G.

1993-05-13

An in vivo screening procedure was established at Battelle's Medical Research and Evaluation Facility (MREF) to evaluate the efficacy of candidate pretreatment compounds in mice challenged with the blood agent, sodium cyanide (NaCN). Male albino mice of ICR outbred stock weighing between 22.5 and 27.5 g are challenged by intramuscular (i.m.) injection, at a volume of 0.5 mL/kg, of a dose of NaCN twice the LD50 of untreated mice as determined on that day of testing. Candidate drugs are tested at fractions of their LD50 or their limit of solubility in the most optimum vehicle and given intraperitoneally (i.p.) tomore » separate groups of mice at either 60 or 15 min prior to NaCN challenge. Sodium thiosulfate (1000 mg/kg)/sodium nitrite (100 mg/kg) controls are injected i.p. only at 60 min prior to challenge. A test compound is deemed effective if, at any of three concentrations tested, or at either pretreatment time, it is statistically more efficacious in preventing lethality than is a negative control substance (candidate compound vehicle).« less

Reversible obstructive sleep apnea caused by occupational exposure to guar gum dust.

PubMed

Leznoff, A; Haight, J S; Hoffstein, V

1986-05-01

This report describes a case of reversible obstructive sleep apnea caused by occupational exposure to an inhaled allergen, guar gum powder. The patient, a pet food plant employee, also experienced severe cough, rhinitis, and conjunctivitis. Skin tests confirmed the specific guar allergy. Pharyngeal cross-sectional area was smaller than normal. Pulmonary function studies, histamine challenge tests, nasal air-flow resistance measurements, and nocturnal polysomnography were performed on 3 separate occasions: while the patient was working at his usual occupation, at the end of a 3-wk holiday, and after a guar dust challenge in an inhalation chamber. Pulmonary function and histamine challenge tests were consistently normal. At the time of the initial tests, nasal resistance was elevated, and nocturnal polysomnography revealed obstructive sleep apnea. After absence from work, obstructive sleep apnea resolved, and the nasal resistance returned to normal. After challenge with guar gum dust, the patient developed increased resistance to nasal air flow, and obstructive sleep apnea reappeared. This case demonstrates that allergy can cause reversible obstructive sleep apnea and that occupational exposure should be considered in the assessment of patients with this disease.

Developing a modified preservative efficacy testing approach as a predictive tool for the evaluation of preservative systems in liquid home care products under variable test conditions.

PubMed

Hoyt, Anne L; Bushman, Don; Lewis, Nathan; Faber, Robert

2012-01-01

How can a formulator have confidence that a preservative system will perform as expected under adverse conditions? Extreme conditions that can lead to the development of "off odors" in the product can be a serious challenge for companies providing home care products in the global market. Formulation and stability testing occur under controlled parameters that simulate limited environmental conditions and microbial challenges are typically performed with a standard inoculum level. While this is an acceptable and dependable process, it does not necessarily assess how well a preservative system can perform under extreme environmental conditions or against unusually high levels of bacterial challenges. This is especially true when formulations are diluted and stored by the end-user. By modifying microbial challenge testing of a liquid dishwashing product to include unexpected dilution schemes, increased microbial assaults, and elevated temperatures, a pattern of preservative efficacy was established. The resulting approach proved to be a useful tool when developing use directions, recommended dilution levels, the overall surfactant system, preservative type, and storage restrictions.

An evaluation of short-term corticosteroid response in perennial allergic rhinitis using histamine and adenosine monophosphate nasal challenge

PubMed Central

Wilson, Andrew M; Sims, Erika J; Orr, Linda C; Robb, Fiona; Lipworth, Brian J

2003-01-01

Aims To evaluate the role of AMP nasal challenge as a measure of short-term treatment response in patients receiving intranasal corticosteroids. Adenosine monophosphate (AMP) challenge has been shown to be a good inflammatory surrogate in the lower airways, but it has not been properly evaluated as a nasal challenge test. Methods Fourteen patients with perennial allergic rhinitis (PAR) were randomized to receive 2 weeks treatment with placebo (PL) or 200 µg intranasal mometasone furoate (MF) once daily in a randomized single-blind crossover study. AMP (25–800 mg ml−1) and histamine (0.25–8 mg ml−1) nasal challenge testing were performed after each treatment period with 30% decrease in minimal cross-sectional area (MCA). Domiciliary symptom data were collected. Results There was a significant (P < 0.05) improvement in PC30 MCA and nasal volume with AMP but not with histamine comparing MF vs PL. This amounted to a 2.8 (95% CI 1.5, 4.0) and 0.7 (95% CI −0.5, 1.9) doubling-dose change for AMP and histamine challenges, respectively. There were significant (P < 0.05) improvements in nasal symptoms and quality of life. Conclusions AMP nasal challenge using acoustic rhinometry may be a useful test to assess short-term treatment response in patient with PAR. PMID:12680883

Toxcast and the Use of Human Relevant In Vitro Exposures ...

EPA Pesticide Factsheets

The path for incorporating new approach methods and technologies into quantitative chemical risk assessment poses a diverse set of scientific challenges. These challenges include sufficient coverage of toxicological mechanisms to meaningfully interpret negative test results, development of increasingly relevant test systems, computational modeling to integrate experimental data, putting results in a dose and exposure context, characterizing uncertainty, and efficient validation of the test systems and computational models. The presentation will cover progress at the U.S. EPA in systematically addressing each of these challenges and delivering more human-relevant risk-based assessments. This abstract does not necessarily reflect U.S. EPA policy. Presentation at the British Toxicological Society Annual Congress on ToxCast and the Use of Human Relevant In Vitro Exposures: Incorporating high-throughput exposure and toxicity testing data for 21st century risk assessments .

Inventory of college challenges for ethnic minority students: psychometric properties of a new instrument in Chinese Americans.

PubMed

Ying, Yu-Wen; Lee, Peter Allen; Tsai, Jeanne L

2004-11-01

The Inventory of College Challenges for Ethnic Minority Students (ICCEMS) is a newly developed instrument that assesses challenges faced by ethnic minority college students across a range of cultural, academic, social, and practical domains. The present study tested the ICCEMS among Chinese American students in an attempt to identify its factor structure and assess its psychometric properties. A total of 13 factor domains emerged. The Cronbach's alpha and 1-month test-retest reliability of the subscales and the overall scale supported their reliability. Both criterion and construct validities were also demonstrated. Chinese American college students faced the greatest challenges in terms of unclear career direction and academic demands. 2004 APA

In vivo diagnosis of allergic diseases--allergen provocation tests.

PubMed

Agache, I; Bilò, M; Braunstahl, G-J; Delgado, L; Demoly, P; Eigenmann, P; Gevaert, P; Gomes, E; Hellings, P; Horak, F; Muraro, A; Werfel, T; Jutel, M

2015-04-01

The allergen challenge test has been the mainstay of diagnosis of allergic diseases for a long time since it offers a direct proof of the clinical relevance of a particular allergen for the allergic disease symptoms and severity. Standardisation and availability for daily practice (including safety issues) are still to be refined but most of the challenge tests have safely crossed the border from research tools to diagnostic tests available for daily practice for a well trained clinical staff. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The association between socio-demographic marginalization and plasma glucose levels at diagnosis of gestational diabetes.

PubMed

Sampson, L; Dasgupta, K; Ross, N A

2014-12-01

We examined the association between socio-demographic marginalization and plasma glucose levels at diagnosis of gestational diabetes in a multi-ethnic and socio-economically diverse patient group. Medical charts at a Toronto gestational diabetes clinic were reviewed for women with a recorded pregnancy between 1 March 2006 and 26 April 2011. One-hour 50-g glucose challenge test values and postal code data were abstracted. Postal codes were merged with 2006 Canadian census data to compute neighbourhood-level ethnic concentration (% recent immigrants, % visible minorities) and material deprivation (% low education, % low income, single-parent households). We compared women in the highest neighbourhood quintiles for both ethnic concentration and material deprivation with all other women to explore an association between marginalization and diagnostic glucose levels. Multivariate regression models of glucose challenge test values and insulin prescription were adjusted for age, prior gestational diabetes, parity and diabetes family history. Among 531 patients with complete glucose challenge test data (mean 11.94 mmol/l, sd 1.83), those in the most marginalized neighbourhoods had 0.43 mmol/l higher glucose challenge test values (95% CI 0.08-0.78) compared with the rest of the study population. Other factors associated with higher glucose challenge test values were prior gestational diabetes (0.59 mmol/l increment, 95% CI 0.19-0.99) and diabetes family history (0.32 mmol/l increment, 95% CI -0.01 to 0.66). Each additional 1 mmol/l glucose challenge test result was associated with an increased likelihood of being prescribed insulin (odds ratio 1.33, 95% CI 1.17-1.51). Women living in the most materially deprived and ethnically concentrated neighbourhoods have higher glucose levels at diagnosis of gestational diabetes. They may need close monitoring for timely initiation of insulin. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

Evaluation of the filtration performance of NIOSH-approved N95 filtering facepiece respirators by photometric and number-based test methods.

PubMed

Rengasamy, Samy; Miller, Adam; Eimer, Benjamin C

2011-01-01

N95 particulate filtering facepiece respirators are certified by measuring penetration levels photometrically with a presumed severe case test method using charge neutralized NaCl aerosols at 85 L/min. However, penetration values obtained by photometric methods have not been compared with count-based methods using contemporary respirators composed of electrostatic filter media and challenged with both generated and ambient aerosols. To better understand the effects of key test parameters (e.g., particle charge, detection method), initial penetration levels for five N95 model filtering facepiece respirators were measured using NaCl aerosols with the aerosol challenge and test equipment employed in the NIOSH respirator certification method (photometric) and compared with an ultrafine condensation particle counter method (count based) for the same NaCl aerosols as well as for ambient room air particles. Penetrations using the NIOSH test method were several-fold less than the penetrations obtained by the ultrafine condensation particle counter for NaCl aerosols as well as for room particles indicating that penetration measurement based on particle counting offers a more difficult challenge than the photometric method, which lacks sensitivity for particles < 100 nm. All five N95 models showed the most penetrating particle size around 50 nm for room air particles with or without charge neutralization, and at 200 nm for singly charged NaCl monodisperse particles. Room air with fewer charged particles and an overwhelming number of neutral particles contributed to the most penetrating particle size in the 50 nm range, indicating that the charge state for the majority of test particles determines the MPPS. Data suggest that the NIOSH respirator certification protocol employing the photometric method may not be a more challenging aerosol test method. Filter penetrations can vary among workplaces with different particle size distributions, which suggests the need for the development of new or revised "more challenging" aerosol test methods for NIOSH certification of respirators.

Positive Skin Test or Specific IgE to Penicillin Does Not Reliably Predict Penicillin Allergy.

PubMed

Tannert, Line Kring; Mortz, Charlotte Gotthard; Skov, Per Stahl; Bindslev-Jensen, Carsten

According to guidelines, patients are diagnosed with penicillin allergy if skin test (ST) result or specific IgE (s-IgE) to penicillin is positive. However, the true sensitivity and specificity of these tests are presently not known. To investigate the clinical relevance of a positive ST result and positive s-IgE and to study the reproducibility of ST and s-IgE. A sample of convenience of 25 patients with positive penicillin ST results, antipenicillin s-IgE results, or both was challenged with their culprit penicillin. Further 19 patients were not challenged, but deemed allergic on the basis of a recent anaphylactic reaction or delayed reactions to skin testing. Another sample of convenience of 18 patients, 17 overlapping with the 25 challenged, with initial skin testing and s-IgE (median, 25; range, 3-121), months earlier (T -1 ), was repeat skin tested and had s-IgE measured (T 0 ), and then skin tested and had s-IgE measured 4 weeks later (T 1 ). Only 9 (36%) of 25 were challenge positive. There was an increased probability of being penicillin allergic if both ST result and s-IgE were positive at T 0 . Positive ST result or positive s-IgE alone did not predict penicillin allergy. Among the 18 patients repeatedly tested, 46.2% (12 of 25) of positive ST results at T -1 were reproducibly positive at T 0 . For s-IgE, 54.2% (14 of 24) positive measurements were still positive at T 0 and 7 converted to positive at T 1 . The best predictor for a clinically significant (IgE-mediated) penicillin allergy is a combination of a positive case history with simultaneous positive ST result and s-IgE or a positive challenge result. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

National Transonic Facility status

NASA Technical Reports Server (NTRS)

Mckinney, L. W.; Bruce, W. E., Jr.; Gloss, B. B.

1989-01-01

The National Transonic Facility (NTF) was operational in a combined checkout and test mode for about 3 years. During this time there were many challenges associated with movement of mechanical components, operation of instrumentation systems, and drying of insulation in the cryogenic environment. Most of these challenges were met to date along with completion of a basic flow calibration and aerodynamic tests of a number of configurations. Some of the major challenges resulting from cryogenic environment are reviewed with regard to hardware systems and data quality. Reynolds number effects on several configurations are also discussed.

Design evolution of the orbiter reaction control subsystem

NASA Technical Reports Server (NTRS)

Taeber, R. J.; Karakulko, W.; Belvins, D.; Hohmann, C.; Henderson, J.

1985-01-01

The challenges of space shuttle orbiter reaction control subsystem development began with selection of the propellant for the subsystem. Various concepts were evaluated before the current Earth storable, bipropellant combination was selected. Once that task was accomplished, additional challenges of designing the system to satisfy the wide range of requirements dictated by operating environments, reusability, and long life were met. Verification of system adequacy was achieved by means of a combination of analysis and test. The studies, the design efforts, and the test and analysis techniques employed in meeting the challenges are described.

Turbines, Wind Tunnels, and Teamwork: The 2017 Collegiate Wind Competition Technical Challenge

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

None

Ten college teams put their turbines to the test at the U.S. Department of Energy’s 2017 Collegiate Wind Competition Technical Challenge, held April 20–22 at the National Wind Technology Center (NWTC). The competition showcased a wide variety of turbine designs and highlighted the competitors’ brilliance, agility, and ingenuity. College students weren’t the only future wind energy experts at the NWTC that weekend: elementary and middle school students tested their turbines—crafted creatively from materials like soda bottles and aluminum foil—in the Colorado KidWind Challenge.

Temperature-mediated differences in bacterial kidney disease expression and survival in Renibacterium salmoninarum-challenged bull trout and other salmonids

USGS Publications Warehouse

Jones, D.T.; Moffitt, C.M.; Peters, K.K.

2007-01-01

Resource managers considering restoration and reconnection of watersheds to protect and enhance threatened populations of bull trout Salvelinus confluentus have little information about the consequences of bacterial kidney disease (BKD) caused by Renibacterium salmoninarum. To better understand the response of bull trout to R. salmoninarum challenge, we conducted several laboratory experiments at two water temperatures. The extent, severity, and lethality of BKD in bull trout were compared with those of similarly challenged lake trout S. namaycush, Arctic char S. alpinus, Chinook salmon Oncorhynchus tshawytscha, and rainbow trout O. mykiss. The lethal dose of bacterial cells necessary to induce 50% mortality (LD50) was 10-fold lower at the 15??C challenge than at the 9??C challenge. Of the species tested, bull trout were relatively resistant to BKD, Arctic char were the most susceptible among Salvelinus species, and Chinook salmon were the most susceptible among Oncorhynchus species tested. Mean time to death was more rapid for all fish tested at 15??C than for fish challenged at 9??C. These results suggest that infection of bull trout with BKD likely poses a low risk to successful restoration of threatened populations. ?? Copyright by the American Fisheries Society 2007.

Effect of lactose on oro-cecal transit in lactose digesters and maldigesters.

PubMed

He, T; Priebe, M G; Welling, G W; Vonk, R J

2006-10-01

The transit time of the small intestine, in addition to lactase activity, may influence lactose digestion and thus play a role in the occurrence of lactose intolerance. The objectives of this study were to investigate the effect of lactose on the oro-cecal transit time (OCTT) in lactose digesters and maldigesters as well as the possible mechanisms underlying these effects. Twenty-eight Chinese subjects and 16 Dutch subjects underwent one glucose and one lactose challenge in two single-blinded tests. Twenty of the Chinese subjects without complaints after the challenge then underwent another lactose challenge. A 6-h symptom score (SSC) was recorded, breath-hydrogen concentration was measured and OCTT after consumption of glucose and lactose was determined with the lactose-[13C] ureide breath test. The lactose digestion index (LDI) was determined in both the Dutch and 20 Chinese subjects with the 13C/2H-glucose test. Lactose digesters (n = 13) and maldigesters (n = 20) were classified based on the results of the LDI and the breath-hydrogen test. The OCTT after the lactose and glucose challenges did not differ in the digesters, whereas in the maldigesters the OCTT, after the lactose challenge, was shorter than that after glucose. There was no difference in OCTT after the glucose challenge between the maldigesters and the digesters. However, the OCTT after the lactose challenge in the maldigesters was shorter than that in the digesters. The LDI of the digesters was significantly higher than that of the maldigesters. The OCTT after the lactose challenge was not correlated to the LDI in the maldigesters nor in the digesters. Based on the SSC after the one glucose and two lactose challenges, a tolerant (n = 7) and an intolerant (n = 5) group were classified in the Chinese subjects. The two groups did not differ in their LDI or OCTT after the lactose challenge. The OCTT after the lactose challenge was not correlated to the SSC or the LDI. Lactose triggers a faster oro-cecal transit in lactose maldigesters, but not in digesters. However, this could not be explained by intestinal distension resulting from the osmotic load posed by maldigested lactose, and thus suggests a direct effect of lactose on intrinsic factors regulating intestinal motility.

Report of a consultation on the optimization of clinical challenge trials for evaluation of candidate blood stage malaria vaccines, 18-19 March 2009, Bethesda, MD, USA.

PubMed

Moorthy, V S; Diggs, C; Ferro, S; Good, M F; Herrera, S; Hill, A V; Imoukhuede, E B; Kumar, S; Loucq, C; Marsh, K; Ockenhouse, C F; Richie, T L; Sauerwein, R W

2009-09-25

Development and optimization of first generation malaria vaccine candidates has been facilitated by the existence of a well-established Plasmodium falciparum clinical challenge model in which infectious sporozoites are administered to human subjects via mosquito bite. While ideal for testing pre-erythrocytic stage vaccines, some researchers believe that the sporozoite challenge model is less appropriate for testing blood stage vaccines. Here we report a consultation, co-sponsored by PATH MVI, USAID, EMVI and WHO, where scientists from all institutions globally that have conducted such clinical challenges in recent years and representatives from regulatory agencies and funding agencies met to discuss clinical malaria challenge models. Participants discussed strengthening and harmonizing the sporozoite challenge model and considered the pros and cons of further developing a blood stage challenge possibly better suited for evaluating the efficacy of blood stage vaccines. This report summarizes major findings and recommendations, including an update on the Plasmodium vivax clinical challenge model, the prospects for performing experimental challenge trials in malaria endemic countries and an update on clinical safety data. While the focus of the meeting was on the optimization of clinical challenge models for evaluation of blood stage candidate malaria vaccines, many of the considerations are relevant for the application of challenge trials to other purposes.

Integration and Testing Challenges of Small, Multiple Satellite Missions: Experiences From The Space Technology 5 Project

NASA Technical Reports Server (NTRS)

Sauerwein, Timothy A.; Gostomski, Thomas

2007-01-01

This brief presentation describes the mechanical and electrical integration activities and environmental testing challenges of the Space Technology 5 (ST5) Project. Lessons learned during this process are highlighted, including performing mechanical activities serially to gain efficiency through repetition and performing electrical activities based on the level of subsystem expertise available.

A Framework for Evidence-Based Licensure of Adaptive Autonomous Systems

DTIC Science & Technology

2016-03-01

insights gleaned to DoD. The autonomy community has identified significant challenges associated with test, evaluation verification and validation of...licensure as a test, evaluation, verification , and validation (TEVV) framework that can address these challenges. IDA found that traditional...language requirements to testable (preferably machine testable) specifications • Design of architectures that treat development and verification of

Toxcast and the Use of Human Relevant In Vitro Exposures: Incorporating High-Throughput Exposure and Toxicity Testing Data for 21st Century Risk Assessments (British Toxicological Society Annual Congress)

EPA Science Inventory

The path for incorporating new approach methods and technologies into quantitative chemical risk assessment poses a diverse set of scientific challenges. These challenges include sufficient coverage of toxicological mechanisms to meaningfully interpret negative test results, dev...

Operational challenges in delivering CD4 diagnostics in sub-Saharan Africa.

PubMed

Thairu, L; Katzenstein, D; Israelski, D

2011-07-01

Access to reliable and low cost CD4 T-cell enumeration to stage illness and monitor anti-retroviral therapy remains elusive in resource-limited settings. We report challenges in delivering CD4 testing using the microcapillary Fluorescence-Activated Cell Sorter (FACS) methodology (Guava EasyCD4 instrument Guava Technologies, Hayward) in Burkina Faso and Zimbabwe. Resources, instruments, reagents, and training were provided to local laboratories within the existing infrastructure and data on CD4 were collected from routine laboratory testing. Challenges encountered included frequent instrument breakdown; poor manufacturer maintenance; difficulties in managing reagent stocks; high technician turnover; reliance on antiquated data management systems; redundant service provision; and lack of repeat testing in male HIV+ patients and in patients with higher CD4 counts after initial staging. While adopting newer, less expensive technologies such as fluorescent platforms and point of care tests can facilitate access to lower cost CD4 testing, our experience suggests that supply chain, corporate commitment to implementation, and community factors also require consideration.

The safety of the H1N1 influenza A vaccine in egg allergic individuals.

PubMed

Greenhawt, Matthew J; Chernin, Anna S; Howe, Laura; Li, James T; Sanders, Georgiana

2010-11-01

The safety of H1N1 vaccine is unknown in egg allergic (EA) recipients. To establish the safety of administering H1N1 vaccine and to evaluate the predictability of H1N1 skin testing in EA patients. In a controlled, prospective trial, H1N1 skin testing and vaccination was compared between EA patients (n = 105) and non-EA controls (n = 19). Those with negative H1N1 skin test results received a full H1N1 dose; those with a positive skin test result received a graded challenge (10%, 90%). Booster vaccine, if required, was given as a single dose from a different lot without prior testing. Prick and intradermal test results were positive in 3 (2.4%) of 124 and 41 (33.1%) of 124 study participants, respectively. Forty-one individuals received a 2-step graded vaccine challenge, including 13 of 25 with a history of egg anaphylaxis. No significant allergic reactions resulted from either method of vaccination or from subsequent booster doses. All study participants received the H1N1 vaccine without significant allergic reactions. Skin testing is unnecessary and does not predict vaccine tolerance. All study participants who received a graded challenge tolerated a single dose booster from a different, untested lot, including 7 individuals with a history of egg-induced anaphylaxis. We recommend administration of H1N1 vaccine to EA children without prior skin testing or graded challenge dosing. Copyright © 2010 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Clinical application of pharmacogenetics: focusing on practical issues.

PubMed

Chang, Matthew T; McCarthy, Jeanette J; Shin, Jaekyu

2015-01-01

Recent large-scale genetic-based studies have transformed the field of pharmacogenetics to identify, characterize and leverage genetic information to inform patient care. Genetic testing can be used to alter drug selection, optimize drug dosing and prevent unnecessary adverse events. As precision medicine becomes the mainstay in the clinic, it becomes critical for clinicians to utilize pharmacogenetics to guide patient care. One primary challenge is identifying patients where genetic tests that can potentially impact patient care. To address this challenge, our review highlights many practical issues clinicians may encounter: identifying candidate patients and clinical laboratories for pharmacogenetic testing, selecting highly curated resources to help asses test validity, reimbursing costs of pharmacogenetic tests, and interpreting of pharmacogenetic test results.

Occupational asthma caused by samba (Triplochiton scleroxylon) wood dust in a professional maker of wooden models of airplanes: a case study.

PubMed

Krawczyk-Szulc, Patrycja; Wiszniewska, Marta; Pałczyński, Cezary; Nowakowska-Świrta, Ewa; Kozak, Anna; Walusiak-Skorupa, Jolanta

2014-06-01

Wood dust is a known occupational allergen that may induce, in exposed workers, respiratory diseases including asthma and allergic rhinitis. Samba (obeche, Triplochiton scleroxylon) is a tropical tree, which grows in West Africa, therefore, Polish workers are rarely exposed to it. This paper describes a case of occupational asthma caused by samba wood dust. The patient with suspicion of occupational asthma due to wood dust was examined at the Department of Occupational Diseases and Clinical Toxicology in the Nofer Institute of Occupational Medicine. Clinical evaluation included: analysis of occupational history, skin prick tests (SPT) to common and occupational allergens, determination of serum specific IgE to occupational allergens, serial spirometry measurements, metacholine challenge test and specific inhalation challenge test with samba dust SPT and specific serum IgE assessment revealed sensitization to common and occupational allergens including samba. Spirometry measurements showed mild obstruction. Metacholine challenge test revealed a high level of bronchial hyperactivity. Specific inhalation challenge test was positive and cellular changes in nasal lavage and induced sputum confirmed allergic reaction to samba. IgE mediated allergy to samba wood dust was confirmed. This case report presents the first documented occupational asthma and rhinitis due to samba wood dust in wooden airplanes model maker in Poland.

Expanding Access to Malaria Diagnosis through Retail Shops in Western Kenya: What Do Shop Workers Think?

PubMed Central

Koech, Beatrice; Obala, Andrew; O'Meara, Wendy Prudhomme

2013-01-01

Background. The common symptoms of malaria reduce the specificity of clinical diagnosis. Presumptive treatment is conventional but can lead to overdiagnosis of malaria, delay of appropriate treatment, overprescription of antimalarials, and drug resistance. Routine use of diagnostic tests can address many of these concerns. Though treatment is often procured from retailers, there is low availability of rapid diagnostic tests for malaria (MRDTs), a simple, inexpensive, and accurate diagnostic solution. We know little about the challenges to expanding access to diagnostics through these outlets. Methods. To understand the perceptions of the benefits and challenges to selling rapid diagnostic tests for malaria, we conducted focus group discussions with antimalarial retailers who serve the residents of the Webuye Health and Demographic Surveillance Site in western Kenya. Results. Medicine retailers perceived MRDTs to be beneficial to their customers and businesses but also included cost, fear of the tests, risks of self-treatment, and regulatory concerns among the challenges to using and selling MRDTs. Conclusion. MRDTs represent a viable approach to increase access to malaria diagnostic testing. Medicine retailers are eager for MRDTs to be made available to them. However, certain challenges remain to implementation in retail outlets and should be addressed in advance. PMID:23766923

Clinical history as a predictor of penicillin skin test outcome.

PubMed

Wong, Benjamin B L; Keith, Paul K; Waserman, Susan

2006-08-01

Up to 10% of the population reports an "allergy" to penicillin, whereas approximately 1.1% has positive penicillin skin test results. Where penicillin skin tests are unavailable, some have advocated using history to decide whether to use a penicillin-related antibiotic. To determine if clinical history predicts penicillin skin test results. Retrospective medical record review of 94 consecutive patients who had previously taken penicillin referred for penicillin allergy. Case histories were taken, penicillin skin tests performed, and an oral challenge recommended if skin test results were negative. Of 91 cases studied, the average patient age was 27 years (range, 6 months to 82 years; 36% female). Fifty-two (57%) experienced hives as their main adverse reaction. Sixteen (18%) had at least 1 positive test result. Of this group, 9 had hives as their main symptom, whereas 1 had respiratory problems and 1 had angioedema. Most patients with positive skin test results had experienced their reaction at least 3 years ago. Regression analysis showed that age, sex, and clinical history, including type of reaction, time of reaction after penicillin ingestion, or time since the last reaction, were not associated with skin test positivity. Seventy-two (96%) of the 75 patients who had negative skin test results underwent oral challenge. Seventy had negative challenge results. The negative predictive value of a negative penicillin skin test result was 97%. Clinical history was not predictive of subsequent penicillin skin test results.

Entry, Descent, and Landing Mission Design for the Crew Exploration Vehicle Thermal Protection System Qualification Flight Test

NASA Technical Reports Server (NTRS)

Ivanov, Mark; Strauss, William; Maddock, Robert

2007-01-01

The TORCH team was challenged to generate the lowest cost mission design solution that meets the CEV aerothermal test objectives on a sub-scale flight article. The test objectives resulted from producing representative lunar return missions and observing the aerothermal envelopes of select surface locations on the CEV. From these aerothermal envelopes, two test boxes were established: one for high shear and one for high radiation. The unique and challenging trajectory design objective for the flight test was to fly through these aerothermal boxes in shear, pressure, heat flux, and radiation while also not over testing. These test boxes, and the max aerothermal limits, became the driving requirements for defining the mission design.

Economic evaluations of point of care testing strategies for active tuberculosis.

PubMed

Zwerling, Alice; Dowdy, David

2013-06-01

Point of care (POC) diagnostics are often hailed as having the potential to transform tuberculosis (TB) control efforts. However, POC testing is better conceptualized as a system of diagnosis and treatment, not simply a test that can provide rapid, deployable results. Economic evaluations may help decision makers allocate scarce resources for TB control, but evaluations of POC testing face unique challenges that include evaluating the full diagnostic system, incorporating implementation costs, translating diagnostic results into health and accounting for downstream treatment costs. For economic evaluations to reach their full potential as decision-making tools for POC testing in TB, these challenges must be understood and addressed.

AGONIST-MEDIATED AIRWAY CHALLENGE: CARDIOPULMONARY INTERACTIONS MODULATE GAS EXCHANGE AND RECOVERY

EPA Science Inventory

ABSTRACT
To better understand the early phase response (0-60 minutes) to airway challenge, we examined cardiopulmonary reactions during ovalbumin (OVA), histamine, and methacholine aerosol challenge tests in guinea pigs. Propranolol and 100% O2 were used to modify the reacti...

Improving Gram stain proficiency in hospital and satellite laboratories that do not have microbiology.

PubMed

Guarner, Jeannette; Street, Cassandra; Matlock, Margaret; Cole, Lisa; Brierre, Francoise

2017-03-01

Consolidation of laboratories has left many hospitals and satellite laboratories with minimal microbiologic testing. In many hospitals and satellite laboratories, Gram stains on primary specimens are still performed despite difficultly in maintaining proficiency. To maintain Gram stain proficiency at a community 450-bed hospital with an active emergency room we designed bimonthly challenges that require reporting Gram staining and morphology of different organisms. The challenges consist of five specimens prepared by the reference microbiology laboratory from cultures and primary specimens. Twenty to 23 medical laboratory scientists participate reading the challenges. Results from the challenges are discussed with each medical laboratory scientists. In addition, printed images from the challenges are presented at huddle to add microbiology knowledge. On the first three challenges, Gram staining was read correctly in 71%-77% of the time while morphology 53%-66%. In the last six challenges correct answers for Gram stain were 77%-99% while morphology 73%-96%. We observed statistically significant improvement when reading Gram stains by providing frequent challenges to medical laboratory scientists. The clinical importance of Gram stain results is emphasized during huddle presentations increasing knowledge and motivation to perform the test for patients.

Influence of Mechanical and Chemical Degradation in the Surface Roughness, Gloss, and Color of Microhybrid Composites.

PubMed

Lemos, Cleidiel Aa; Mauro, Silvio J; Dos Santos, Paulo H; Briso, Andre Lf; Fagundes, Ticiane C

2017-04-01

The aim of this study was to investigate the association of different degradations on the roughness, gloss, and color changes of microhybrid composites. Ten specimens were prepared for Charisma, Amelogen Plus, Point 4, and Opallis resins. Surfaces were polished and baseline measurements of roughness, gloss, and color were recorded. Specimens were then submitted to chemical and mechanical challenges, and the specimens were reevaluated. Roughness and gloss were analyzed by Kruskal -Wallis and Dunn's test (p < 0.05). Color change (ΔE) was analyzed by one-way analysis of variance and Tukey's tests (p < 0.05). The initial and final data were compared using the Wilcoxon test (p < 0.05). Spearman test checked the correlation between the roughness and gloss (p < 0.05). Regarding surface roughness and gloss, there was no difference between composites before challenges. However, all composites showed a significant increase of roughness after challenges, with highest values for Charisma. The gloss was influenced by challenges, evidencing the best gloss for Point 4. Charisma showed the highest value of color change. There was no correlation between surface roughness and gloss for the initial analysis, and after the challenges. Composites were influenced by association of challenges, and Charisma showed the highest changes for roughness, gloss, and color. The type of composite resin influenced the properties of materials, which are surface roughness, gloss, and color change. The dentist should be aware of the performance of different brands, to choose the correct required composite resin for each type of patient or region to be restored.

Fish allergy in atopic children.

PubMed

Peng, Y H; Shyur, S D; Chang, C L; Lai, C L; Chu, S H; Wu, W C; Wu, C Y

2001-12-01

The prevalence of fish allergy among 11 atopic children with elevated levels of specific immunoglobulin (Ig) E for cod was determined. None of the children had a history of fish allergy. All of the children had asthma and allergic rhinitis and 5 of them had also atopic dermatitis. The children underwent allergy skin tests (codfish, tuna, catfish, salmon, flounder, and bass), specific IgE tests (salmon, trout, tuna, eel, and mackerel), and food challenge tests. Skin tests in cod-specific IgE-positive children were positive for codfish in 4 children, tuna in 2, catfish in 2, salmon in 6, flounder in one, and bass in 2. Three children had elevated specific IgE for salmon, 5 for trout, 8 for tuna, 4 for eel, and 4 for mackerel. Oral fish challenge with 10 g of fish did not result in positive reaction in any of the children. In conclusion, a positive food challenge test provided the only definitive confirmation of fish allergy, whereas positive allergy skin tests or positive specific IgE tests were less reliable. Skin tests and in vitro specific IgE assays were not correlated with clinical symptoms of fish allergy, and the results of these 2 tests did not correlate with each other in this study.

Increased fall risk is associated with elevated co-contraction about the ankle during static balance challenges in older adults.

PubMed

Nelson-Wong, Erika; Appell, Ryan; McKay, Mike; Nawaz, Hannah; Roth, Joanna; Sigler, Robert; Third, Jacqueline; Walker, Mark

2012-04-01

Falls are a leading contributor to disability in older adults. Increased muscle co-contraction in the lower extremities during static and dynamic balance challenges has been associated with aging, and also with a history of falling. Co-contraction during static balance challenges has not been previously linked with performance on clinical tests designed to ascertain fall risk. The purpose of this study was to investigate the relationship between co-contraction about the ankle during static balance challenges with fall risk on a commonly used dynamic balance assessment, the Four Square Step Test (FSST). Twenty-three volunteers (mean age 73 years) performed a series of five static balance challenges (Romberg eyes open/closed, Sharpened Romberg eyes open/closed, and Single Leg Standing) with continuous electromyography (EMG) of bilateral tibialis anterior and gastrocnemius muscles. Participants then completed the FSST and were categorized as 'at-risk' or 'not-at-risk' to fall based on a cutoff time of 12 s. Co-contraction was quantified with co-contraction index (CCI). CCI during narrow base conditions was positively correlated with time to complete FSST. High CCIs during all static balance challenges with the exception of Romberg stance with eyes closed were predictive of being at-risk to fall based on FSST time, odds ratio 19.3. The authors conclude that co-contraction about the ankle during static balance challenges can be predictive of performance on a dynamic balance test.

Randomised controlled trial of three day versus 10 day intravenous antibiotics in acute pyelonephritis: effect on renal scarring

PubMed Central

Benador, D; Neuhaus, T; Papazyan, J; Willi, U; Engel-Bicik, I; Nadal, D; Slosman, D; Mermillod, B; Girardin, E

2001-01-01

BACKGROUND—Acute pyelonephritis often leaves children with permanent renal scarring.
AIMS—To compare the prevalence of scarring following initial treatment with antibiotics administered intravenously for 10 or three days.
METHODS—In a prospective two centre trial, 220 patients aged 3 months to 16 years with positive urine culture and acute renal lesions on initial DMSA scintigraphy, were randomly assigned to receive intravenous ceftriaxone (50 mg/kg once daily) for 10 or three days, followed by oral cefixime (4 mg/kg twice daily) to complete a 15 day course. After three months, scintigraphy was repeated in order to diagnose renal scars.
RESULTS—Renal scarring developed in 33% of the 110 children in the 10 day intravenous group and 36% of the 110 children in the three day group. Children older than 1 year had more renal scarring than infants (42% (54/129) and 24% (22/91), respectively). After adjustment for age, sex, duration of fever before treatment, degree of inflammation, presence of vesicoureteric reflux, and the patients' recruitment centres, there was no significant difference between the two treatments on renal scarring. During follow up, 15 children had recurrence of urinary infection with no significant difference between the two treatment groups.
CONCLUSION—In children with acute pyelonephritis, initial intravenous treatment for 10 days, compared with three days, does not significantly reduce the development of renal scarring.

 PMID:11207174

Lead poisoning from an unexpected source in a 4-month-old infant.

PubMed

Shannon, M

1998-06-01

Childhood lead poisoning is characteristically a disease that occurs between the second and third years of life, generally resulting from the child's ingestion of lead-based paint or dust. However, lead poisoning may also appear in the first year of life. The case of a 4-month-old infant is reported in which the preparation of infant formula in a lead-soldered samovar (urn) resulted in venous blood lead levels as high as 46 microg/dl. The samovar had been brought into the United States by the parents while on a visit to Iran. The infant was placed on chelation therapy with parenteral CaNa2EDTA followed by oral meso-2,3-dimercaptosuccinic acid (DMSA) and d-penicillamine. This resulted in a rapid and substantial reduction in the blood lead level. Lead poisoning in infancy may have unusual etiologies such as in utero transmission of lead by lead-poisoned women. Because sources of lead poisoning in infancy may be unusual, a detailed environmental investigation may be necessary to identify the exact source. Children exposed to lead in the first 2 years of life have a special vulnerability to the neurotoxicity of lead, with the risk of enduring developmental handicaps. Continued public health initiatives to remove lead from the environment, in conjunction with routine lead screening of young children, will be key in meeting the goal of the Centers for Disease Control and Prevention to eliminate childhood lead poisoning by the year 2011.

Lead poisoning from an unexpected source in a 4-month-old infant.

PubMed Central

Shannon, M

1998-01-01

Childhood lead poisoning is characteristically a disease that occurs between the second and third years of life, generally resulting from the child's ingestion of lead-based paint or dust. However, lead poisoning may also appear in the first year of life. The case of a 4-month-old infant is reported in which the preparation of infant formula in a lead-soldered samovar (urn) resulted in venous blood lead levels as high as 46 microg/dl. The samovar had been brought into the United States by the parents while on a visit to Iran. The infant was placed on chelation therapy with parenteral CaNa2EDTA followed by oral meso-2,3-dimercaptosuccinic acid (DMSA) and d-penicillamine. This resulted in a rapid and substantial reduction in the blood lead level. Lead poisoning in infancy may have unusual etiologies such as in utero transmission of lead by lead-poisoned women. Because sources of lead poisoning in infancy may be unusual, a detailed environmental investigation may be necessary to identify the exact source. Children exposed to lead in the first 2 years of life have a special vulnerability to the neurotoxicity of lead, with the risk of enduring developmental handicaps. Continued public health initiatives to remove lead from the environment, in conjunction with routine lead screening of young children, will be key in meeting the goal of the Centers for Disease Control and Prevention to eliminate childhood lead poisoning by the year 2011. Images Figure 1 PMID:9618346

[First urinary tract infection in healthy infants: epidemiology, diagnosis and treatment].

PubMed

Capdevila Cogul, E; Martín Ibáñez, I; Mainou Cid, C; Toral Rodríguez, E; Cols Roig Mf; Agut Quijano, T; Caritg Bosch, J; Camarasa Piqué, F

2001-10-01

Urinary tract infection (UTI) is one of the most common infections in infants. It presents certain peculiarities compared with other pediatric age groups in terms of symptomatology, diagnosis and the therapeutic approach employed to prevent sequels. To analyze the epidemiology, clinical and laboratory findings, etiology, diagnosis and treatment of first-time UTI in healthy infants. Between January and December 1999, we performed a retrospective study of 131 previously healthy infants admitted to our hospital with a diagnosis of first-time UTI. Demographic data, clinical characteristics, urine dipstick, urinalysis and urine culture (vesical catheterization), blood cell count and PCR, kidney ultrasonography, voiding cystourethrogram and DMSA scintigraphy were reviewed. We studied 131 patients (median age: 90 days). In infants younger than 30 days, UTI was more prevalent in males. The most frequent symptom was fever (73.3 %). Seventy-one patients fulfilled the criteria for acute pyelonephritis. The presence of nitrituria was low. Escherichia coli was isolated in 90.1 % of the patients. Voiding cystourethrogram detected vesicoureteric reflux in 18.4 % of the patients. Scintigraphy revealed renal scarring in 15.1 %. No significant correlations were found between renal scarring in late scintigraphy and a diagnosis of acute pyelonephritis and/or alterations in the cystourethrogram. Fever was the main symptom. E. coli was the most commonly isolated microorganism. Nitrituria had low sensitivity in infants. Ultrasonography had low specificity. Scintigraphy showed the highest sensitivity and specificity in the detection of renal scarring. Predictability improved when scintigraphy was performed a few months after acute infection.

Addressing the Analytic Challenges of Cross-Sectional Pediatric Pneumonia Etiology Data.

PubMed

Hammitt, Laura L; Feikin, Daniel R; Scott, J Anthony G; Zeger, Scott L; Murdoch, David R; O'Brien, Katherine L; Deloria Knoll, Maria

2017-06-15

Despite tremendous advances in diagnostic laboratory technology, identifying the pathogen(s) causing pneumonia remains challenging because the infected lung tissue cannot usually be sampled for testing. Consequently, to obtain information about pneumonia etiology, clinicians and researchers test specimens distant to the site of infection. These tests may lack sensitivity (eg, blood culture, which is only positive in a small proportion of children with pneumonia) and/or specificity (eg, detection of pathogens in upper respiratory tract specimens, which may indicate asymptomatic carriage or a less severe syndrome, such as upper respiratory infection). While highly sensitive nucleic acid detection methods and testing of multiple specimens improve sensitivity, multiple pathogens are often detected and this adds complexity to the interpretation as the etiologic significance of results may be unclear (ie, the pneumonia may be caused by none, one, some, or all of the pathogens detected). Some of these challenges can be addressed by adjusting positivity rates to account for poor sensitivity or incorporating test results from controls without pneumonia to account for poor specificity. However, no classical analytic methods can account for measurement error (ie, sensitivity and specificity) for multiple specimen types and integrate the results of measurements for multiple pathogens to produce an accurate understanding of etiology. We describe the major analytic challenges in determining pneumonia etiology and review how the common analytical approaches (eg, descriptive, case-control, attributable fraction, latent class analysis) address some but not all challenges. We demonstrate how these limitations necessitate a new, integrated analytical approach to pneumonia etiology data. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Addressing the Analytic Challenges of Cross-Sectional Pediatric Pneumonia Etiology Data

PubMed Central

Feikin, Daniel R.; Scott, J. Anthony G.; Zeger, Scott L.; Murdoch, David R.; O’Brien, Katherine L.; Deloria Knoll, Maria

2017-01-01

Abstract Despite tremendous advances in diagnostic laboratory technology, identifying the pathogen(s) causing pneumonia remains challenging because the infected lung tissue cannot usually be sampled for testing. Consequently, to obtain information about pneumonia etiology, clinicians and researchers test specimens distant to the site of infection. These tests may lack sensitivity (eg, blood culture, which is only positive in a small proportion of children with pneumonia) and/or specificity (eg, detection of pathogens in upper respiratory tract specimens, which may indicate asymptomatic carriage or a less severe syndrome, such as upper respiratory infection). While highly sensitive nucleic acid detection methods and testing of multiple specimens improve sensitivity, multiple pathogens are often detected and this adds complexity to the interpretation as the etiologic significance of results may be unclear (ie, the pneumonia may be caused by none, one, some, or all of the pathogens detected). Some of these challenges can be addressed by adjusting positivity rates to account for poor sensitivity or incorporating test results from controls without pneumonia to account for poor specificity. However, no classical analytic methods can account for measurement error (ie, sensitivity and specificity) for multiple specimen types and integrate the results of measurements for multiple pathogens to produce an accurate understanding of etiology. We describe the major analytic challenges in determining pneumonia etiology and review how the common analytical approaches (eg, descriptive, case-control, attributable fraction, latent class analysis) address some but not all challenges. We demonstrate how these limitations necessitate a new, integrated analytical approach to pneumonia etiology data. PMID:28575372

Challenger Anniversary Resource Tape

NASA Technical Reports Server (NTRS)

1996-01-01

This commemorative video marks the tenth anniversary, January 28, 1986, of the ninth Challenger flight and the seven astronauts onboard who died when the Challenger exploded 73 seconds into flight. The flight crew was comprised of Cmdr. Francis R. Scobee, Pilot Michael J. Smith, and Mission Specialists Judith A. Resnik, Ellison S. Onizuka, Ronald E. McNair, Gregory Jarvis (Hughes Aircraft representative), and S. Christie McAuliffe (teacher). The flight crew is shown performing preflight training, physiological tests, environmental tests, press conferences, prelaunch activities, and launch activities. The Challenger explosion is shown from both the launch site and from the control center. Various rescue operations, news coverage, and shots of the wreckage after salvage are also presented. President Ronald Reagan is shown giving a tribute at the memorial service for the flight crew. The video ends with a flyby salute and pictures of each of the members of the Challenger.

Glucose screening tests during pregnancy

MedlinePlus

Oral glucose tolerance test - pregnancy; OGTT - pregnancy; Glucose challenge test - pregnancy; Gestational diabetes - glucose screening ... first step, you will have a glucose screening test: You DO NOT need to prepare or change ...

Assessing Academic Challenges for Their Contribution to Cognitive Development.

ERIC Educational Resources Information Center

McCormick, David F.; Whittington, M. Susie

2000-01-01

Challenges (assignments, activities, tests) incorporated into agriculture classes were evaluated using Bloom's Taxonomy. The cognitive level varied by course and type of activity. Effectiveness depended on selecting challenges appropriate for the material, requiring higher-order thinking, and rewarding students for work at higher cognitive levels.…

[CHALLENGES IN THE DIAGNOSIS OF CUSHING'S SYNDROME IN THE MODERN ERA].

PubMed

Saiegh, Leonard; Sheikh-Ahmad, Mohammad; Reut, Maria; Jubran, Yousef; Shechner, Carmela

2015-12-01

Cushing's syndrome results from prolonged and excessive exposure to medically prescribed corticosteroids, or from excess endogenous cortisol secretion. When endogenous cortisol secretion is suspected, several screening tests are conducted in order to confirm or to rule out the diagnosis. In recent years, as the cut-off point of cortisol concentration on the 1 mg overnight dexamethasone suppression test was lowered, the prevalence of Cushing's syndrome has increased, and more cases of mild syndromes, with negative results on one or more screening tests, have increasingly been reported. In this paper, we will describe the various screening tests used for Cushing's syndrome, and will discuss their degree of sensitivity in the diagnosis of mild cases. We conclude that, in cases of mild syndromes, the sensitivity of some tests appears to be notably lower than has been reported. Until recently, the major challenge has been to distinguish between pseudo-Cushing's states and Cushing's syndrome. Today, however, the challenge has become to avoid misdiagnosis of mild cases, presenting with normal results on some screening tests. The sensitivity of urinary free cortisol seems to be lower than previously reported. Therefore, we recommend not to rely solely on this test in ruling out Cushing's syndrome.

Development of Cryogenic Engine for GSLV MkIII: Technological Challenges

NASA Astrophysics Data System (ADS)

Praveen, RS; Jayan, N.; Bijukumar, KS; Jayaprakash, J.; Narayanan, V.; Ayyappan, G.

2017-02-01

Cryogenic engine capable of delivering 200 kN thrust is being developed for the first time in the country by ISRO for powering the upper stage of GSLV Mk-III, the next generation launch vehicle of ISRO capable of launching four tonne class satellites to Geo-synchronous Transfer Orbit(GTO). Development of this engine started a decade ago when various sub-systems development and testing were taken up. Starting with injector element development, the design, realization and testing of the major sub-systems viz the gas generator, turbopumps, start-up system and thrust chamber have been successfully done in a phased manner before conducting a series of developmental tests in the integrated engine mode. Apart from the major sub-systems, many critical components like the igniter, control components etc were independently developed and qualified. During the development program many challenges were faced in almost all areas of propulsion engineering. Systems engineering of the engine was another key challenge in the realization. This paper gives an outlook on various technological challenges faced in the key areas related to the engine development, insight to the solutions and measures taken to overcome the challenges.

Fast Magnetotail Reconnection: Challenge to Global MHD Modeling

NASA Astrophysics Data System (ADS)

Kuznetsova, M. M.; Hesse, M.; Rastaetter, L.; Toth, G.; de Zeeuw, D.; Gombosi, T.

2005-05-01

Representation of fast magnetotail reconnection rates during substorm onset is one of the major challenges to global MHD modeling. Our previous comparative study of collisionless magnetic reconnection in GEM Challenge geometry demonstrated that the reconnection rate is controlled by ion nongyrotropic behavior near the reconnection site and that it can be described in terms of nongyrotropic corrections to the magnetic induction equation. To further test the approach we performed MHD simulations with nongyrotropic corrections of forced reconnection for the Newton Challenge setup. As a next step we employ the global MHD code BATSRUS and test different methods to model fast magnetotail reconnection rates by introducing non-ideal corrections to the induction equation in terms of nongyrotropic corrections, spatially localized resistivity, or current dependent resistivity. The BATSRUS adaptive grid structure allows to perform global simulations with spatial resolution near the reconnection site comparable with spatial resolution of local MHD simulations for the Newton Challenge. We select solar wind conditions which drive the accumulation of magnetic field in the tail lobes and subsequent magnetic reconnection and energy release. Testing the ability of global MHD models to describe magnetotail evolution during substroms is one of the elements of science based validation efforts at the Community Coordinated Modeling Center.

Student Design Challenges in Capillary Flow

NASA Technical Reports Server (NTRS)

Stocker, Dennis P.; Wollman, Andrew; Hall, Nancy R.; Weislogel, Mark; DeLombard, Richard

2016-01-01

For some grade 8-12 students, capillary flow has bridged the gap between the classroom and research facility, from normal gravity to microgravity. In the past four years, NASA and the Portland State University (PSU) have jointly challenged students to design test cells, using Computer-Aided Design (CAD), to study capillary action in microgravity as PSU has done on the International Space Station (ISS). Using the student-submitted CAD drawings, the test cells were manufactured by PSU and tested in their 2.1-second drop tower. The microgravity results were made available online for student analysis and reporting. Over 100 such experiments have been conducted, where there has been participation from 15 states plus a German school for the children of U.S. military personnel. In 2016, a related NASA challenge was held in partnership with the ASGSR, again, based on the research conducted by PSU. In this challenge, grade 9-12 students designed and built devices using capillary action to launch droplets as far as possible in NASAs 2.2 Second Drop Tower. Example results will be presented by students at this conference. The challenges engage students in ISS science and technology and can inspire them to pursue technical careers.

Simulating New Drop Test Vehicles and Test Techniques for the Orion CEV Parachute Assembly System

NASA Technical Reports Server (NTRS)

Morris, Aaron L.; Fraire, Usbaldo, Jr.; Bledsoe, Kristin J.; Ray, Eric; Moore, Jim W.; Olson, Leah M.

2011-01-01

The Crew Exploration Vehicle Parachute Assembly System (CPAS) project is engaged in a multi-year design and test campaign to qualify a parachute recovery system for human use on the Orion Spacecraft. Test and simulation techniques have evolved concurrently to keep up with the demands of a challenging and complex system. The primary simulations used for preflight predictions and post-test data reconstructions are Decelerator System Simulation (DSS), Decelerator System Simulation Application (DSSA), and Drop Test Vehicle Simulation (DTV-SIM). The goal of this paper is to provide a roadmap to future programs on the test technique challenges and obstacles involved in executing a large-scale, multi-year parachute test program. A focus on flight simulation modeling and correlation to test techniques executed to obtain parachute performance parameters are presented.

Challenges and solutions for high-volume testing of silicon photonics

NASA Astrophysics Data System (ADS)

Polster, Robert; Dai, Liang Yuan; Oikonomou, Michail; Cheng, Qixiang; Rumley, Sebastien; Bergman, Keren

2018-02-01

The first generation of silicon photonic products is now commercially available. While silicon photonics possesses key economic advantages over classical photonic platforms, it has yet to become a commercial success because these advantages can be fully realized only when high-volume testing of silicon photonic devices is made possible. We discuss the costs, challenges, and solutions of photonic chip testing as reported in the recent research literature. We define and propose three underlying paradigms that should be considered when creating photonic test structures: Design for Fast Coupling, Design for Minimal Taps, and Design for Parallel Testing. We underline that a coherent test methodology must be established prior to the design of test structures, and demonstrate how an optimized methodology dramatically reduces the burden when designing for test, by reducing the needed complexity of test structures.

ACToR – Aggregated Computational Toxicology Resource ...

EPA Pesticide Factsheets

This presentation reviews the US EPAs reaction to the challenge of the NRC on the future of toxicity testing through the development of the ACTor Project and the ToxRef database. This presentation reviews the US EPAs reaction to the challenge of the NRC on the future of toxicity testing through the development of the ACTor Project and the ToxRef database.

Limited Knowledge of Fraction Representations Differentiates Middle School Students with Mathematics Learning Disability (Dyscalculia) versus Low Mathematics Achievement

ERIC Educational Resources Information Center

Mazzocco, Michele M. M.; Myers, Gwen F.; Lewis, Katherine E.; Hanich, Laurie B.; Murphy, Melissa M.

2013-01-01

Fractions pose significant challenges for many children, but for some children those challenges persist into high school. Here we administered a fractions magnitude comparison test to 122 children, from Grades 4 to 8, to test whether their knowledge of fractions typically learned early in the sequence of formal math instruction (e.g., fractions…

Exit Exams, High-Stakes Testing, and Students with Disabilities: A Persistent Challenge

ERIC Educational Resources Information Center

Yell, Mitchell L.; Katsiyannis, Antonis; Collins, James C.; Losinski, Mickey

2012-01-01

The demands for accountability in education have led to an increase in high-stakes testing practices in public schools. Accountability can be seen at the high school level in the use of exit examinations (hereafter "exit exams") that students must pass to receive a diploma and graduate from high school. One of the most challenging issues…

Using Mathematics-Curriculum Based Measures to Predict Outcomes on the Mathematics Portion of the Mississippi Curriculum Test, Second Edition

ERIC Educational Resources Information Center

Hogan-Samuel, Eutrophia Lenora

2012-01-01

The nation is challenged with improving the mathematics achievement of its students. No Child Left Behind holds schools, districts, and states accountable for improving student achievement. Because high stakes tests are given at the end of the school year, schools are presented with the challenging task of developing or purchasing reliable…

Cross-protection between experimental anti-leptospirosis bacterins

PubMed Central

Dib, Cristina Corsi; Gonçales, Amane Paldês; de Morais, Zenaide Maria; de Souza, Gisele Oliveira; Miraglia, Fabiana; Abreu, Patricia Antonia Estima; Vasconcellos, Silvio Arruda

2014-01-01

We investigated the existence of cross-protection between two anti-leptospirosis monovalent experimental bacterins produced with two strains of Leptospira serogroup Pomona: Fromm strain of serovar Kennewicky, isolated from pigs in the United States, and strain GR6 of serovar Pomona isolated from pigs in Brazil. Both were added of aluminum hydroxide as an adjuvant. Experimental bacterins were tested with the hamster potency test in order to assess protection provided against the disease and against the establishment of kidney infection. Controls were polyvalent commercial vaccine produced with Leptospira strains isolated outside Brazil, which included a representative of Pomona serovar, or Sorensen solution added of aluminum hydroxide adjuvant. The challenge was performed with cross-strains of serogroup Pomona tested in accordance with international standards established for the potency test. After 21 days of the challenge, survivors were killed to evaluate the condition of Leptospira renal carrier. Experimental bacterins protected hamsters against homologous and heterologous strains, demonstrating the existence of cross-protection. The commercial vaccine protected the hamsters challenged with both strains, but there was a high proportion of animals diagnosed as renal carriers when the challenge was performed with strain GR6, isolated from pigs in Brazil. PMID:25477946

Replacement of fishmeal by spirulina Arthrospira platensis affects growth, immune related-gene expression in gibel carp (Carassius auratus gibelio var. CAS III), and its challenge against Aeromonas hydrophila infection.

PubMed

Cao, Shenping; Zhang, Peiyu; Zou, Tao; Fei, Shuzhan; Han, Dong; Jin, Junyan; Liu, Haokun; Yang, Yunxia; Zhu, Xiaoming; Xie, Shouqi

2018-05-15

The present study examined the effect of dietary spirulina, Arthrospira platensis on growth performance, blood physiological indices, immune-related gene expressions and resistance of juvenile gibel carp against Aeromonas hydrophila infection. Four isonitrogenous (360 g kg -1 ) and isolipidic (90 g kg -1 ) diets were formulated with containing different levels of spirulina powder of 0 g (SP0, the control diet), 3.38 g (SP3.38), 6.76 g (SP6.76) and 13.52 g (SP13.52) per 100 g diet to replace 0%, 25%, 50% and 100% of fishmeal protein, respectively. And each diet was randomly assigned to triplicate tanks (150-L capacity per each) and each tank was stocked with 22 fish (15.37 ± 0.06 g). Fish were fed one of the tested diets up to satiation twice a day for 46 days. A challenge test was carried out after the feeding trial by injecting Aeromonas hydrophila intraperitoneally for 7 days. The results showed that fish growth, feeding rate in groups SP3.38 and SP6.76 were significantly higher than those of groups SP0 and SP13.52 (P < 0.05). Feed efficiency and protein retention rate had no significant difference among all tested groups. Plasma superoxide dismutase and phagocyte activity of blood leukocytes significantly increased in the spirulina-fed fish groups at 12-h post the bacterial challenge (P < 0.05). Both pre and post challenge test, plasma lysozyme activities in spirulina-fed groups were significantly higher than that in the control group (P < 0.05). Plasma malondialdehyde got the lowest value in the SP13.52 group before and after the challenge test. The transcriptional levels of TLR2 (Toll like receptor 2), myeloid differentiation factor 88 (MyD88), Toll/IL-1 receptor domain-containing adaptor protein (TIRAP), interleukin-1β (IL-1β) and tumor necrosis factor-α1 (TNF-α1) in spleen and kidney significantly increased post the bacterial challenge compared to the pre challenge. And the relative expressions of the immune-related genes of spirulina-fed fish groups were higher than those of the control group before and after the challenge test. The 7-day cumulative survival rate after the bacterial challenge was highest in the SP3.38 group (P < 0.05). The present results indicated that low dietary inclusion of spirulina significantly enhanced the immune response of gibel carp partly through TLR2 pathway and 3.38% of dietary spirulina was recommended for the juveniles based on the growth and immune response. Copyright © 2018. Published by Elsevier Ltd.

Having Fun and Accepting Challenges Are Natural Instincts: Jigsaw Puzzles to Challenge Students and Test Their Abilities While Having Fun!

ERIC Educational Resources Information Center

Rodenbaugh, Hanna R.; Lujan, Heidi L.; Rodenbaugh, David W.; DiCarlo, Stephen E.

2014-01-01

Because jigsaw puzzles are fun, and challenging, students will endure and discover that persistence and grit are rewarded. Importantly, play and fun have a biological place just like sleep and dreams. Students also feel a sense of accomplishment when they have completed a puzzle. Importantly, the reward of mastering a challenge builds confidence…

Caffeine challenge test and panic disorder: a systematic literature review.

PubMed

Vilarim, Marina Machado; Rocha Araujo, Daniele Marano; Nardi, Antonio Egidio

2011-08-01

This systematic review aimed to examine the results of studies that have investigated the induction of panic attacks and/or the anxiogenic effect of the caffeine challenge test in patients with panic disorder. The literature search was performed in PubMed, Biblioteca Virtual em Saúde and the ISI Web of Knowledge. The words used for the search were caffeine, caffeine challenge test, panic disorder, panic attacks and anxiety disorder. In total, we selected eight randomized, double-blind studies where caffeine was administered orally, and none of them controlled for confounding factors in the analysis. The percentage of loss during follow-up ranged between 14.3% and 73.1%. The eight studies all showed a positive association between caffeine and anxiogenic effects and/or panic disorder.

Use of Genetic Testing for Primary Immunodeficiency Patients.

PubMed

Heimall, Jennifer R; Hagin, David; Hajjar, Joud; Henrickson, Sarah E; Hernandez-Trujillo, Hillary S; Tan, Yuval; Kobrynski, Lisa; Paris, Kenneth; Torgerson, Troy R; Verbsky, James W; Wasserman, Richard L; Hsieh, Elena W Y; Blessing, Jack J; Chou, Janet S; Lawrence, Monica G; Marsh, Rebecca A; Rosenzweig, Sergio D; Orange, Jordan S; Abraham, Roshini S

2018-04-01

Genetic testing plays a critical role in diagnosis for many primary immunodeficiency diseases. The goals of this report are to outline some of the challenges that clinical immunologists face routinely in the use of genetic testing for patient care. In addition, we provide a review of the types of genetic testing used in the diagnosis of PID, including their strengths and limitations. We describe the strengths and limitations of different genetic testing approaches for specific clinical contexts that raise concern for specific PID disorders in light of the challenges reported by the clinical immunologist members of the CIS in a recent membership survey. Finally, we delineate the CIS's recommendations for the use of genetic testing in light of these issues.

Research notes : solar powered markers not up to challenge.

DOT National Transportation Integrated Search

2008-06-01

ODOT performed preliminary tests on eight different models of solar powered raised pavement markers. These included environmental tests (extreme temperatures, immersion), optical performance tests, and observation tests. Federal Highway Administratio...

African American church-based HIV testing and linkage to care: assets, challenges and needs.

PubMed

Stewart, Jennifer M; Thompson, Keitra; Rogers, Christopher

2016-01-01

The US National HIV AIDS strategy promotes the use of faith communities to lessen the burden of HIV in African American communities. One specific strategy presented is the use of these non-traditional venues for HIV testing and co-location of services. African American churches can be at the forefront of this endeavour through the provision of HIV testing and linkage to care. However, there are few interventions to promote the churches' involvement in both HIV testing and linkage to care. We conducted 4 focus groups (n = 39 participants), 4 interviews and 116 surveys in a mixed-methods study to examine the feasibility of a church-based HIV testing and linkage to care intervention in Philadelphia, PA, USA. Our objectives were to examine: (1) available assets, (2) challenges and barriers and (3) needs associated with church-based HIV testing and linkage to care. Analyses revealed several factors of importance, including the role of the church as an access point for testing in low-income neighbourhoods, challenges in openly discussing the relationship between sexuality and HIV, and buy-in among church leadership. These findings can support intervention development and necessitate situating African American church-based HIV testing and linkage to care interventions within a multi-level framework.

Challenging Gait Conditions Predict 1-Year Decline in Gait Speed in Older Adults With Apparently Normal Gait

PubMed Central

Perera, Subashan; VanSwearingen, Jessie M.; Hile, Elizabeth S.; Wert, David M.; Studenski, Stephanie A.

2011-01-01

Background Mobility often is tested under a low challenge condition (ie, over a straight, uncluttered path), which often fails to identify early mobility difficulty. Tests of walking during challenging conditions may uncover mobility difficulty that is not identified with usual gait testing. Objective The purpose of this study was to determine whether gait during challenging conditions predicts decline in gait speed over 1 year in older people with apparently normal gait (ie, gait speed of ≥1.0 m/s). Design This was a prospective cohort study. Methods Seventy-one older adults (mean age=75.9 years) with a usual gait speed of ≥1.0 m/s participated. Gait was tested at baseline under 4 challenging conditions: (1) narrow walk (15 cm wide), (2) stepping over obstacles (15.24 cm [6 in] and 30.48 cm [12 in]), (3) simple walking while talking (WWT), and (4) complex WWT. Usual gait speed was recorded over a 4-m course at baseline and 1 year later. A 1-year change in gait speed was calculated, and participants were classified as declined (decreased ≥0.10 m/s, n=18), stable (changed <0.10 m/s, n=43), or improved (increased ≥0.10 m/s, n=10). Analysis of variance was used to compare challenging condition cost (usual − challenging condition gait speed difference) among the 3 groups. Results Participants who declined in the ensuing year had a greater narrow walk and obstacle walk cost than those who were stable or who improved in gait speed (narrow walk cost=0.43 versus 0.33 versus 0.22 m/s and obstacle walk cost=0.35 versus 0.26 versus 0.13 m/s). Simple and complex WWT cost did not differ among the groups. Limitations The participants who declined in gait speed over time walked the fastest, and those who improved walked the slowest at baseline; thus, the potential contribution of regression to the mean to the findings should not be overlooked. Conclusions In older adults with apparently normal gait, the assessment of gait during challenging conditions appears to uncover mobility difficulty that is not identified by usual gait testing. PMID:22003167

Design of Electrical Systems for Rocket Propulsion Test Facilities at the John C. Stennis Space Center

NASA Technical Reports Server (NTRS)

Hughes, Mark S.; Davis, Dawn M.; Bakker, Henry J.; Jensen, Scott L.

2007-01-01

This viewgraph presentation reviews the design of the electrical systems that are required for the testing of rockets at the Rocket Propulsion Facility at NASA Stennis Space Center (NASA SSC). NASA/SSC s Mission in Rocket Propulsion Testing Is to Acquire Test Performance Data for Verification, Validation and Qualification of Propulsion Systems Hardware. These must be accurate reliable comprehensive and timely. Data acquisition in a rocket propulsion test environment is challenging: severe temporal transient dynamic environments, large thermal gradients, vacuum to 15 ksi pressure regimes SSC has developed and employs DAS, control systems and control systems and robust instrumentation that effectively satisfies these challenges.

Benefit of the basophil activation test in deciding when to reintroduce cow's milk in allergic children.

PubMed

Rubio, A; Vivinus-Nébot, M; Bourrier, T; Saggio, B; Albertini, M; Bernard, A

2011-01-01

Oral challenges are required to establish the persistence or resolution of IgE-mediated cow's milk allergy (CMA). Determining the appropriate timing for challenging is the main difficulty. The benefit of the basophil activation test (BAT) in predicting a child's reaction to the oral challenge was evaluated and compared to the specific IgE and skin prick tests' (SPT) results. One hundred and twelve consecutive children with CMA admitted for an oral challenge to reassess their allergy were included. Allergen-induced basophil activation was detected as a CD63-upregulation by flow cytometry. Thirty-six children (32%) had a positive oral challenge. The percentage of activated basophils in patients with a positive challenge (mean = 20.9; SD = 18.8) was significantly higher than that of patients with a negative challenge (mean = 3.9; SD = 9.8, P < 0.0001), and was well correlated with the eliciting dose of cow's milk (P < 0.0001). The BAT had an efficiency of 90%, a sensitivity of 91%, a specificity of 90%, and positive and negative predictive values of 81% and 96% in detecting persistently allergic patients. The area under the ROC curve was 0.866. These scores were higher than those obtained with SPT and IgE values, whichever positivity cut-point was chosen. Referring to a decisional algorithm combining BAT, specific IgE and SPT allowed the correct identification of 94% of patients as tolerant or persistently allergic to cow's milk proteins (CMP) in our cohort. The BAT could be a valuable tool in the management of paediatric CMA in addition to specific IgE quantification and SPT, by contributing in determining whether an oral challenge can safely be undertaken. © 2010 John Wiley & Sons A/S.

The Impact of Challenging Geometry and Measurement Units on the Achievement of Grade 2 Students

ERIC Educational Resources Information Center

Gavin, M. Katherine; Casa, Tutita M.; Adelson, Jill L.; Firmender, Janine M.

2013-01-01

The primary goal of Project M[superscript 2] was to develop and field-test challenging geometry and measurement units for all K-2 students. This article reports on the achievement results for students in Grade 2 at 12 urban and suburban sites in 4 states using the Iowa Tests of Basic Skills (ITBS) mathematics concepts subtest and an open-response…

Using Project-Based Learning to Design, Build, and Test Student-Made Photometer by Measuring the Unknown Concentration of Colored Substances

ERIC Educational Resources Information Center

Diawati, Chansyanah; Liliasari; Setiabudi, Agus; Buchari

2018-01-01

Students learned the principles and practice of photometry through project-based learning. They addressed the challenge of measuring the unknown concentration of a colored substance using a photometer they were required to design, build, and test. Then, they used that instrument to carry out the experiment and fulfill the challenge. A photometer…

Thermal Protection for Mars Sample Return Earth Entry Vehicle: A Grand Challenge for Design Methodology and Reliability Verification

NASA Technical Reports Server (NTRS)

Venkatapathy, Ethiraj; Gage, Peter; Wright, Michael J.

2017-01-01

Mars Sample Return is our Grand Challenge for the coming decade. TPS (Thermal Protection System) nominal performance is not the key challenge. The main difficulty for designers is the need to verify unprecedented reliability for the entry system: current guidelines for prevention of backward contamination require that the probability of spores larger than 1 micron diameter escaping into the Earth environment be lower than 1 million for the entire system, and the allocation to TPS would be more stringent than that. For reference, the reliability allocation for Orion TPS is closer to 11000, and the demonstrated reliability for previous human Earth return systems was closer to 1100. Improving reliability by more than 3 orders of magnitude is a grand challenge indeed. The TPS community must embrace the possibility of new architectures that are focused on reliability above thermal performance and mass efficiency. MSR (Mars Sample Return) EEV (Earth Entry Vehicle) will be hit with MMOD (Micrometeoroid and Orbital Debris) prior to reentry. A chute-less aero-shell design which allows for self-righting shape was baselined in prior MSR studies, with the assumption that a passive system will maximize EEV robustness. Hence the aero-shell along with the TPS has to take ground impact and not break apart. System verification will require testing to establish ablative performance and thermal failure but also testing of damage from MMOD, and structural performance at ground impact. Mission requirements will demand analysis, testing and verification that are focused on establishing reliability of the design. In this proposed talk, we will focus on the grand challenge of MSR EEV TPS and the need for innovative approaches to address challenges in modeling, testing, manufacturing and verification.

Skin test sensitivity to mouse predicts allergic symptoms to nasal challenge in urban adults.

PubMed

Chong, Laura K; Ong, Mary Jane; Curtin-Brosnan, Jean; Matsui, Elizabeth C

2010-01-01

Epidemiologic studies have shown an association between mouse allergen exposure and asthma morbidity among urban populations, but confirmatory challenge studies in community populations have not been performed. This study was designed to examine the clinical relevance of mouse sensitization using a nasal challenge model. Forty-nine urban adults with asthma underwent skin-prick testing (SPT) and intradermal testing (IDT) with mouse epithelia extract. A positive SPT was defined as a net wheal size ≥3 mm and a positive IDT was defined as a net wheal size ≥6 mm using a 1:100 dilution of extract (1:10 w/v was obtained from Greer Laboratories (Lenoir, NC) as a single lot [Mus m 1 concentration = 2130 ng/mL]). Mouse-specific IgE (m-IgE) was measured by ImmunoCAP (Phadia, Uppsala, Sweden). Nasal challenge was performed with increasing concentrations of mouse epithelia extract and symptoms were assessed by visual analog scale. A positive challenge was defined as a 20-mm increase in the scale. The age range of the 49 participants was 18-50 years; 41% were men and 86% were black. Fourteen participants were SPT(+) to mouse, 15 participants were SPT(-) but (IDT(+)), and 20 participants were negative on both SPT(-) and IDT(-) (SPT(-)/IDT(-)). Sixty-four percent of the SPT(+) group, 40% of the IDT(+) group, and 20% of the SPT(-)/IDT(-) group had a positive nasal challenge. Sixty-seven percent (10/15) of those who were either SPT(+) or m-IgE(+) had a positive nasal challenge. SPT or the combination of SPT plus m-IgE performed best in diagnosing mouse allergy. The great majority of mouse-sensitized urban adults with asthma appear to have clinically relevant sensitization. Urban adults with asthma should be evaluated for mouse sensitization using SPT or SPT plus m-IgE testing.

Diagnostic challenges of childhood asthma.

PubMed

Bakirtas, Arzu

2017-01-01

Diagnosis of asthma in childhood is challenging. Both underdiagnosis and overdiagnosis of asthma are important issues. The present review gives information about challenging factors for an accurate diagnosis of childhood asthma. Although underdiagnosis of asthma in childhood has always been the most important diagnostic problem, overdiagnosis of asthma has also been increasingly recognized. This is probably due to diagnosis of asthma based on symptoms and signs alone. Demonstration of variable airflow obstruction by lung function tests is the most common asthma diagnostic tests used in practice and is therefore strongly recommended in children who can cooperate. Recently, an asthma guideline combining the clinical and economic evidences with sensitivity and specificity of diagnostic procedures was developed to improve accuracy of diagnosis and to avoid overdiagnosis. This guideline provided an algorithmic clinical and cost-effective approach and included fractional exhaled nitric oxide measurement as one of the diagnostic tests in addition to lung function. Diagnosis of asthma in children should be made by combining relevant history with at least two confirmatory diagnostic tests whenever possible. Diagnosis based on short-period treatment trials should be limited to young children who are unable to cooperate with these tests.

Status of Cognitive Testing of Adults in India

PubMed Central

Porrselvi, A. P.; Shankar, V.

2017-01-01

The assessment of cognitive function is a challenging yet an integral component of psychological, psychiatric, and neurological evaluation. Cognitive assessment tools either can be administered quickly for screening for neurocognitive disorders or can be comprehensive and detailed to identify cognitive deficits for the purpose of localization, diagnosis, and rehabilitation. This article is a comprehensive review of published research that discusses the current challenges for cognitive testing in India, available tools used for the assessment of cognitive function in India, and future directions for cognitive testing in India. PMID:29184333

Genetic testing in congenital heart disease: ethical considerations.

PubMed

Lin, Kimberly Y; D'Alessandro, Lisa C A; Goldmuntz, Elizabeth

2013-01-01

On March 16, 2012, the Ethics of the Heart 2012: Ethical and Policy Challenges in Pediatric and Adult Congenital Heart Disease Conference took place in Philadelphia, Pennsylvania. The first session focused on the ethics surrounding genetic testing in patients with congenital heart disease. Summarized here is the introductory presentation given by Dr Elizabeth Goldmuntz entitled "The Role of Genetic Testing in Congenital Heart Disease," followed by a case presentation given by Dr Lisa D'Alessandro. The case and the panel discussion that ensued highlight several ethical principles and challenges in this unique patient population.

Performances on the CogState and Standard Neuropsychological Batteries Among HIV Patients Without Dementia

PubMed Central

Overton, Edgar Turner; Kauwe, John S.K.; Paul, Rob; Tashima, Karen; Tate, David F.; Patel, Pragna; Carpenter, Chuck; Patty, David; Brooks, John T.; Clifford, David B

2013-01-01

HIV-associated neurocognitive disorders (HAND) remain prevalent but challenging to diagnose particularly among non-demented individuals. To determine whether a brief computerized battery correlates with formal neurocognitive testing, we identified 46 HIV-infected persons who had undergone both formal neurocognitive testing and a brief computerized battery. Simple detection tests correlated best with formal neuropsychological testing. By multivariable regression model, 53% of the variance in the composite Global Deficit Score was accounted for by elements from the brief computerized tool (p<0.01). These data confirm previous correlation data with the computerized battery, yet illustrate remaining challenges for neurocognitive screening. PMID:21877204

Managing the Mars Science Laboratory Thermal Vacuum Test for Safety and Success

NASA Technical Reports Server (NTRS)

Evans, Jordan P.

2010-01-01

The Mars Science Laboratory is a NASA/JPL mission to send the next generation of rover to Mars. Originally slated for launch in 2009, development problems led to a delay in the project until the next launch opportunity in 2011. Amidst the delay process, the Launch/Cruise Solar Thermal Vacuum Test was undertaken as risk reduction for the project. With varying maturity and capabilities of the flight and ground systems, undertaking the test in a safe manner presented many challenges. This paper describes the technical and management challenges and the actions undertaken that led to the ultimate safe and successful execution of the test.

Failure of introduction of food allergens after negative oral food challenge tests in children.

PubMed

van der Valk, J P M; Gerth van Wijk, R; Vergouwe, Y; de Jong, N W

2015-08-01

One of the purposes to perform an oral food challenge (FC) test is to avoid unnecessary elimination of food allergens. In case of a negative FC test result, the food can be introduced. It is, however, unknown if patients act according to the outcome of the test. This study evaluates the rate of introduction of peanut, hazelnut, cow's milk or hen's egg allergens after a negative FC test. We investigated the introduction rate of children (0-18 years) with a negative FC test visiting the Department of Allergology, Erasmus Medical Centre Rotterdam from 2008 till 2013 and the factors that influence the rate of introduction. Patients were asked to complete a comprehensive questionnaire about their FC test. In total, 157 (38% girls, mean age during challenge 6.9 years) participated in the study. Of these FC tests, 104 (56%) were followed by a successful introduction, 30 (16%) by a partly introduction (traces or processed foods) and 52 (28%) by a failed introduction. Peanut and hazelnut showed a statistically significant lower successful introduction rate. Age, gender, symptoms during FC test, dietary advice and time period to introduction significantly influenced the rate of introduction. One fourth of the children with failure of introducing foods experienced symptoms during the introduction. More than one quarter of all children with a negative FC test result did not introduce the food. The FC test in its current form does not achieve its objective for this group of children.

Sensory-Challenge Balance Exercises Improve Multisensory Reweighting in Fall-Prone Older Adults.

PubMed

Allison, Leslie K; Kiemel, Tim; Jeka, John J

2018-04-01

Multisensory reweighting (MSR) deficits in older adults contribute to fall risk. Sensory-challenge balance exercises may have value for addressing the MSR deficits in fall-prone older adults. The purpose of this study was to examine the effect of sensory-challenge balance exercises on MSR and clinical balance measures in fall-prone older adults. We used a quasi-experimental, repeated-measures, within-subjects design. Older adults with a history of falls underwent an 8-week baseline (control) period. This was followed by an 8-week intervention period that included 16 sensory-challenge balance exercise sessions performed with computerized balance training equipment. Measurements, taken twice before and once after intervention, included laboratory measures of MSR (center of mass gain and phase, position, and velocity variability) and clinical tests (Activities-specific Balance Confidence Scale, Berg Balance Scale, Sensory Organization Test, Limits of Stability test, and lower extremity strength and range of motion). Twenty adults 70 years of age and older with a history of falls completed all 16 sessions. Significant improvements were observed in laboratory-based MSR measures of touch gain (P = 0.006) and phase (P = 0.05), Berg Balance Scale (P = 0.002), Sensory Organization Test (P = 0.002), Limits of Stability Test (P = 0.001), and lower extremity strength scores (P = 0.005). Mean values of vision gain increased more than those for touch gain, but did not reach significance. A balance exercise program specifically targeting multisensory integration mechanisms improved MSR, balance, and lower extremity strength in this mechanistic study. These valuable findings provide the scientific rationale for sensory-challenge balance exercise to improve perception of body position and motion in space and potential reduction in fall risk.

Halothane and halothane/succinylcholine induced malignant hyperthermia (porcine stress syndrome) in a population of Ontario boars.

PubMed

Seeler, D C; McDonell, W N; Basrur, P K

1983-07-01

This paper recounts a study of the prevalence of malignant hyperthermia in a population of boars entering the Record of Performance Test Station at New Hamburg, Ontario over a period of ten months. The literature is briefly reviewed and an account of the present status of malignant hyperthermia (porcine stress syndrome) in Ontario boars using the halothane or halothane/succinylcholine screening tests is presented. It was determined in this population of boars that there was a 1.5% prevalence rate of malignant hyperthermia susceptible boars. This was based on a five minute halothane challenge carried out on 786 boars from 107 herds. The halothane reactors came from a total of eight herds or 7.5% of the total number of herds. A majority of 58.3% of the animals reacted after the three minute mark of the halothane challenge. In contrast, an 18.0% prevalence rate was determined using halothane/succinylcholine challenge on 123 boars. This further identified an additional eight herds with the problem, bringing the total to 16 or 15% of the total number of herds. It is suggested that the prevalence of malignant hyperthermia in Ontario breeding herds is much higher than was originally thought and that the halothane challenge is an inadequate screening test for this trait if the intention is to remove the genetic trait from the breeding herd. At the same time halothane challenge testing will identify those animals which have a strong susceptibility to the trait and if used on key breeding stock will help to maintain some control on the condition until a more definitive test is readily available.(ABSTRACT TRUNCATED AT 250 WORDS)

College Access Improves for Black Students but for Which Ones?

ERIC Educational Resources Information Center

Cokley, Kevin; Obaseki, Victor; Moran-Jackson, Karen; Jones, Leonie; Vohra-Gupta, Shetal

2016-01-01

The challenges for increasing opportunities and college access for black students typically focus on the traditional barriers related to academic preparation, the racial gap in standardized test scores, and dropping out of high school. While these challenges remain, new and emerging challenges to college access are also important to discuss. They…

Will learning to solve one-step equations pose a challenge to 8th grade students?

NASA Astrophysics Data System (ADS)

Ngu, Bing Hiong; Phan, Huy P.

2017-08-01

Assimilating multiple interactive elements simultaneously in working memory to allow understanding to occur, while solving an equation, would impose a high cognitive load. Element interactivity arises from the interaction between elements within and across operational and relational lines. Moreover, operating with special features (e.g. negative pronumeral) poses additional challenge to master equation solving skills. In an experiment, 41 8th grade students (girls = 16, boys = 25) sat for a pre-test, attended a session about equation solving, completed an acquisition phase which constituted the main intervention and were tested again in a post-test. The results showed that at post-test, students performed better on one-step equations tapping low rather than high element interactivity knowledge. In addition, students performed better on those one-step equations that contained no special features. Thus, both the degree of element interactivity and the operation with special features affect the challenge posed to 8th grade students on learning how to solve one-step equations.

CD-sens can be a reliable and easy-to-use complement in the diagnosis of allergic rhinitis.

PubMed

Nopp, A; Cardell, L O; Johansson, S G O

2013-01-01

A reproducible standard for a graded allergen response in allergic rhinitis is lacking. The aim was to evaluate basophil allergen threshold sensitivity, CD-sens, as a diagnostic complement to nasal allergen challenge. Twenty-six patients with a history of allergic rhinitis due to grass pollen were intranasally challenged and nasal symptom score and peak nasal inspiratory flow (PNIF) changes were determined after 15 min. A 20% decrease in PNIF or a symptom score ≥2 were considered a positive test. A blood sample for CD-sens was drawn before each challenge. Eighteen patients were tested twice. CD-sens agreed with the positive or negative nasal symptom score in 22/26 and PNIF in 24/26 patients. After the second challenge, 14/18 patients had the same symptom, 17/18 the same PNIF, while all had identical CD-sens classification. CD-sens appears to be a reproducible test for diagnosis of allergic rhinitis with great advantages also for follow-up of disease development and treatment effects. Copyright © 2012 S. Karger AG, Basel.

Mitigating Interconnection Challenges of the High Penetration Utility-Interconnected Photovoltaic (PV) in the Electrical Distribution Systems: Cooperative Research and Development Final Report, CRADA Number CRD-14-563

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

Chakraborty, Sudipta

Various interconnection challenges exist when connecting distributed PV into the electrical distribution grid in terms of safety, reliability, and stability of the electric power systems. Some of the urgent areas for research, as identified by inverter manufacturers, installers and utilities, are potential for transient overvoltage from PV inverters, multi-inverter anti-islanding, impact of smart inverters on volt-VAR support, impact of bidirectional power flow, and potential for distributed generation curtailment solutions to mitigate grid stability challenges. Under this project, NREL worked with SolarCity to address these challenges through research, testing and analysis at the Energy System Integration Facility (ESIF). Inverters from differentmore » manufacturers were tested at ESIF and NREL's unique power hardware-in-the-loop (PHIL) capability was utilized to evaluate various system-level impacts. Through the modeling, simulation, and testing, this project eliminated critical barriers on high PV penetration and directly supported the Department of Energy's SunShot goal of increasing the solar PV on the electrical grid.« less

Comparison the Serum STREM1 Levels Between Children with Upper and Lower UTI.

PubMed

Ehsanipour, Fahime; Noorbakhsh, Samileh; Zarabi, Vida; Movahedi, Zahra; Rahimzadeh, Nahid

2017-01-01

Pyelonephritis is the most common and important infection among Iranian pediatric population. Differentiation between upper and lower Urinary Tract Infection (UTI) is often difficult based on clinical data. Therefore, definite diagnosis is helpful for choosing appropriate antibiotic and decision for hospital admission. The main purpose of this study was todetermine the diagnostic value of serum STREM-1 level in children suspicious to UTI and differentiation of upper UTI and lower UTI. This prospective cross sectional study (2010-2011) was performed to evaluate and compare the serum level of STREM- 1 (pg. /ml) in 36 diagnosed UTI patients (24 upper and 12 lower UTI) with 25 normal children (without UTI) in Rasoul Akram hospital, Tehran, Iran. The mean age of studied children was 3.64 years; 24 male and 37 female. Urinary analysis and urine culture were performed for all UTI cases and only the positive cultured cases with the same microorganism were enrolled in the study. Distinguishing the upper from lower UTI was done on the basis of clinical manifestation and laboratory tests and confirmed by Imaging studies (ultra sonography /or DMSA scan). Blood sampling was taken from all children and centrifuged .The level of STREM-1 (pg /ml) in all sera was determined by Enzyme immunoassay technique (Human TREM-1 immunoassay Sandwich test, Quantikine, R&D systems, Minneapolis; USA). Cut-off levels for STREM-1 were illustrated by ROC curve. The p<0.05 was considered as significant for differences between groups. The mean of STREM -1level had significant difference between overall cases of UTI (427.72pg/ml) and controls (124.24 pg. /ml; P =0.000) ; with cutoff point 111.5 pg./ml ; it had 83.3% sensitivity; and 60 % specificity to distinguish UTI from control. Serum STREM -1 level had no significantly difference between the upper and lower UTI (500pg/ml vs. 283 pg. /ml, P value=0.1) with cutoff point 132 pg./ml it had 83.3% sensitivity ; and 60 % specificity to distinguish upper UTI from lower UTI. Our study demonstrates that even low amount of serum STREM-1 (111.5 pg./ml) has 83.3% sensitivity ; and 60 % specificity to distinguish the UTI from normal cases (P value =0.000) but higher level (132 pg./ml) was needed for definite diagnosis (83.3% sensitivity; 60 % specificity) of upper and lower UTI. It is concluded that serum STREM-1 level test is a valuable tool for early diagnosis of the normal cases with false positive urine culture, or in highly suspicious upper UTI cases with false negative urine culture. Indeed higher titer of this biomarker could be helpful for discriminating the upper from lower UTI. Therefore adding this new biologic marker (STREM-1) to previous ones (CRP, PCT) is suggested to prevent the unnecessary hospital admission and empiric antibiotic therapy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

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

None

In this project, three production home builders—K. Hovnanian Homes, David Weekley Homes, and Transformations, Inc.—partnered with Building America team Building Science Corporation to evaluate the certification of five test homes to the new DOE Challenge Home program performance standard (now DOE Zero Energy Ready Home program). The builders identified key benefits and barriers that impacted the certification of the test homes, and the likelihood of whether DOE Challenge Home certification would be pursued in future homes

Methodical Challenges Concerning the Draw-A-Scientist Test: A Critical View about the Assessment and Evaluation of Learners' Conceptions of Scientists

ERIC Educational Resources Information Center

Reinisch, Bianca; Krell, Moritz; Hergert, Susann; Gogolin, Sarah; Krüger, Dirk

2017-01-01

Students' and pre-service teachers' conceptions of scientists have been assessed in a variety of studies. One of the most commonly used instruments is the Draw-A-Scientist Test (DAST) which offers the advantage that no verbal skills are needed by the participants. In some studies, methodical challenges related to the DAST have been discussed; for…

Computational fragment-based screening using RosettaLigand: the SAMPL3 challenge

NASA Astrophysics Data System (ADS)

Kumar, Ashutosh; Zhang, Kam Y. J.

2012-05-01

SAMPL3 fragment based virtual screening challenge provides a valuable opportunity for researchers to test their programs, methods and screening protocols in a blind testing environment. We participated in SAMPL3 challenge and evaluated our virtual fragment screening protocol, which involves RosettaLigand as the core component by screening a 500 fragments Maybridge library against bovine pancreatic trypsin. Our study reaffirmed that the real test for any virtual screening approach would be in a blind testing environment. The analyses presented in this paper also showed that virtual screening performance can be improved, if a set of known active compounds is available and parameters and methods that yield better enrichment are selected. Our study also highlighted that to achieve accurate orientation and conformation of ligands within a binding site, selecting an appropriate method to calculate partial charges is important. Another finding is that using multiple receptor ensembles in docking does not always yield better enrichment than individual receptors. On the basis of our results and retrospective analyses from SAMPL3 fragment screening challenge we anticipate that chances of success in a fragment screening process could be increased significantly with careful selection of receptor structures, protein flexibility, sufficient conformational sampling within binding pocket and accurate assignment of ligand and protein partial charges.

Crowdsourcing the creation of image segmentation algorithms for connectomics.

PubMed

Arganda-Carreras, Ignacio; Turaga, Srinivas C; Berger, Daniel R; Cireşan, Dan; Giusti, Alessandro; Gambardella, Luca M; Schmidhuber, Jürgen; Laptev, Dmitry; Dwivedi, Sarvesh; Buhmann, Joachim M; Liu, Ting; Seyedhosseini, Mojtaba; Tasdizen, Tolga; Kamentsky, Lee; Burget, Radim; Uher, Vaclav; Tan, Xiao; Sun, Changming; Pham, Tuan D; Bas, Erhan; Uzunbas, Mustafa G; Cardona, Albert; Schindelin, Johannes; Seung, H Sebastian

2015-01-01

To stimulate progress in automating the reconstruction of neural circuits, we organized the first international challenge on 2D segmentation of electron microscopic (EM) images of the brain. Participants submitted boundary maps predicted for a test set of images, and were scored based on their agreement with a consensus of human expert annotations. The winning team had no prior experience with EM images, and employed a convolutional network. This "deep learning" approach has since become accepted as a standard for segmentation of EM images. The challenge has continued to accept submissions, and the best so far has resulted from cooperation between two teams. The challenge has probably saturated, as algorithms cannot progress beyond limits set by ambiguities inherent in 2D scoring and the size of the test dataset. Retrospective evaluation of the challenge scoring system reveals that it was not sufficiently robust to variations in the widths of neurite borders. We propose a solution to this problem, which should be useful for a future 3D segmentation challenge.

Addressing challenges to MMPI-2-RF-based testimony: questions and answers.

PubMed

Ben-Porath, Yossef S

2012-11-01

Introduction of a new version of a psychological test brings with it challenges that can be accentuated by the adversarial nature of the legal process. In the case of the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF), these challenges can be addressed by becoming familiar with the rationale for and the methods used in revising the inventory, the information contained in the test manuals, and the growing peer-reviewed literature on the test. Potential challenges to MMPI-2-RF-based testimony are identified in this article and discussed in question and answer format. The questions guiding this discussion are based on the Daubert factors, established in 1993 by the US Supreme Court as criteria for gauging the scientific validity of proffered expert testimony. The answers to these questions apply more broadly to testimony in depositions, pre-trial hearings, and at trial. Consideration of the MMPI-2-RF in light of the Daubert factors indicates that the instrument has been subjected to extensive empirical testing and that a substantial peer-reviewed literature is available to guide and support its use. Information about the known and potential rate of error associated with MMPI-2-RF scores is available, and standard procedures for administration, scoring, and interpretation of the inventory are detailed in the test administration manual. Indicators of MMPI-2-RF acceptance can be cited, and criticisms of the MMPI-2-RF can be addressed with information available in the test documents and an extensive, modern, and actively growing peer-reviewed literature.

Effect of Paneer and Cheese Consumption on Salivary Acidogenicity and Calcium Concentration: A Comparative Study.

PubMed

Somaraj, Vinej; Shenoy, Rekha P; Panchmal, Ganesh Shenoy; Jodalli, Praveen S; Sonde, Laxminarayan; Nagaraj, Kundapur

2018-01-01

To assess and compare the salivary pH reversal phenomenon and calcium concentration in subjects consuming paneer and cheese after an acidogenic challenge and also to compare the salivary pH measurements using pH strips and a portable pen-type pH meter. Sixty caries free undergraduate students were randomly selected and divided into two group: 1. paneer; 2. cheese. After determining the resting salivary pH using pH strips and a pen-type pH meter, participants were subjected to an acidogenic challenge (10% sucrose). Following consumption of test foods (10-gram cubes), salivary pH was measured at intervals of 5, 10, 15, 30 and 60 min to record the time taken for the salivary pH to return to baseline. Colorimetric salivary calcium concentration was estimated (Biochemical Analyzer) at baseline and after 60 min of test food consumption. The statistical tests used were Shapiro-Wilk's test for normality, repeated measures ANOVA, and the independent t-test. Test meals reversed the fall in pH after acidogenic challenge starting at 5 min and returning to baseline values after 30 min in both groups (p = 1.000). Colorimetric estimates showed higher salivary calcium concentrations with paneer (p < 0.001). The pen-type pH meter showed superior efficiency in terms of time (p < 0.001) compared to pH strips. The salivary pH reversal phenomenon was evident after consumption of both paneer and cheese following the acidogenic challenge. Consumption of paneer significantly increased salivary calcium concentration. The pen-type pH meter proved to be more efficient.

Caffeine challenge test in panic disorder and depression with panic attacks.

PubMed

Nardi, Antonio E; Lopes, Fabiana L; Valença, Alexandre M; Freire, Rafael C; Veras, André B; de-Melo-Neto, Valfrido L; Nascimento, Isabella; King, Anna Lucia; Mezzasalma, Marco A; Soares-Filho, Gastão L; Zin, Walter A

2007-01-01

Our aim was to observe if patients with panic disorder (PD) and patients with major depression with panic attacks (MDP) (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria) respond in a similar way to the induction of panic attacks by an oral caffeine challenge test. We randomly selected 29 patients with PD, 27 with MDP, 25 with major depression without panic attacks (MD), and 28 healthy volunteers. The patients had no psychotropic drug for at least a 4-week period. In a randomized double-blind experiment performed in 2 occasions 7 days apart, 480 mg caffeine and a caffeine-free (placebo) solution were administered in a coffee form and anxiety scales were applied before and after each test. A total of 58.6% (n = 17) of patients with PD, 44.4% (n = 12) of patients with MDP, 12.0% (n = 3) of patients with MD, and 7.1% (n= 2) of control subjects had a panic attack after the 480-mg caffeine challenge test (chi(2)(3) = 16.22, P = .001). The patients with PD and MDP were more sensitive to caffeine than were patients with MD and healthy volunteers. No panic attack was observed after the caffeine-free solution intake. The patients with MD had a lower heart rate response to the test than all the other groups (2-way analysis of variance, group by time interaction with Greenhouse-Geisser correction: F(3,762) = 2.85, P = .026). Our data suggest that there is an association between panic attacks, no matter if associated with PD or MDP, and hyperreactivity to an oral caffeine challenge test.

2016 ROVER CHALLENGE EVENTS

NASA Image and Video Library

2015-01-08

2016 ROVER CHALLENGE EVENTS AT THE U.S. SPACE AND ROCKET CENTER IN HUNTSVILLE, ALABAMA. NATIONAL AND INTERNATIONAL COLLEGE AND HIGH SCHOOL STUDENTS COME TOGETHER TO TEST THEIR ENGINEERING SKILLS OVER A SIMULATED OUTER PLANET OBSTACLE COURSE.

Direct-field acoustic testing of a flight system : logistics, challenges, and results.

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

Stasiunas, Eric Carl; Gurule, David Joseph; Babuska, Vit

2010-10-01

Before a spacecraft can be considered for launch, it must first survive environmental testing that simulates the launch environment. Typically, these simulations include vibration testing performed using an electro-dynamic shaker. For some spacecraft however, acoustic excitation may provide a more severe loading environment than base shaker excitation. Because this was the case for a Sandia Flight System, it was necessary to perform an acoustic test prior to launch in order to verify survival due to an acoustic environment. Typically, acoustic tests are performed in acoustic chambers, but because of scheduling, transportation, and cleanliness concerns, this was not possible. Instead, themore » test was performed as a direct field acoustic test (DFAT). This type of test consists of surrounding a test article with a wall of speakers and controlling the acoustic input using control microphones placed around the test item, with a closed-loop control system. Obtaining the desired acoustic input environment - proto-flight random noise input with an overall sound pressure level (OASPL) of 146.7 dB-with this technique presented a challenge due to several factors. An acoustic profile with this high OASPL had not knowingly been obtained using the DFAT technique prior to this test. In addition, the test was performed in a high-bay, where floor space and existing equipment constrained the speaker circle diameter. And finally, the Flight System had to be tested without contamination of the unit, which required a contamination bag enclosure of the test unit. This paper describes in detail the logistics, challenges, and results encountered while performing a high-OASPL, direct-field acoustic test on a contamination-sensitive Flight System in a high-bay environment.« less

Rapid Automated Antimicrobial Susceptibility Testing of Streptococcus pneumoniae by Use of the bioMerieux VITEK 2

PubMed Central

Jorgensen, James H.; Barry, Arthur L.; Traczewski, M. M.; Sahm, Daniel F.; McElmeel, M. Leticia; Crawford, Sharon A.

2000-01-01

The VITEK 2 is a new automated instrument for rapid organism identification and susceptibility testing. It has the capability of performing rapid susceptibility testing of Streptococcus pneumoniae with specially configured cards that contain enriched growth medium and antimicrobial agents relevant for this organism. The present study compared the results of testing of a group of 53 challenge strains of pneumococci with known resistance properties and a collection of clinical isolates examined in two study phases with a total of 402 and 416 isolates, respectively, with a prototype of the VITEK 2. Testing was conducted in three geographically separate laboratories; the challenge collection was tested by all three laboratories, and the unique clinical isolates were tested separately by the individual laboratories. The VITEK 2 results of tests with 10 antimicrobial agents were compared to the results generated by the National Committee for Clinical Laboratory Standards reference broth microdilution MIC test method. Excellent interlaboratory agreement was observed with the challenge strains. The overall agreement within a single twofold dilution of MICs defined by the VITEK 2 and reference method with the clinical isolates was 96.3%, although there were a number of off-scale MICs that could not be compared. The best agreement with the clinical isolates was achieved with ofloxacin and chloramphenicol (100%), and the lowest level of agreement among those drugs with sufficient on-scale MICs occurred with trimethoprim-sulfamethoxazole (89.7%). Overall there were 1.3% very major, 6.6% minor, and no major interpretive category errors encountered with the clinical isolates, although >80% of the minor interpretive errors involved only a single log2 dilution difference. The mean time for generation of susceptibility results with the clinical isolates was 8.1 h. The VITEK 2 provided rapid, reliable susceptibility category determinations with both the challenge and clinical isolates examined in this study. PMID:10921932

Removal of Viruses in Drinking Water- Ultrafiltration Module with a Cut Fiber, Dow Chemical Company - Dow Water & Process Solutions, SFD-2880 - Ultrafiltration Module

EPA Science Inventory

The purpose of this verification was a cut fiber challenge study for the Dow Chemical Company SFD-2880 UF membrane module. MS2 coliphage virus was the surrogate challenge organism. The challenge tests followed the requirements of the Department of Health Victoria (Australia) Dr...

Genetic Testing Integration Panels (GTIPs): A novel approach for considering integration of direct-to-consumer and other new genetic tests into patient care

PubMed Central

Uhlmann, Wendy R.; Sharp, Richard R.

2014-01-01

There has been a dramatic increase in the number of genetic tests available but few tests have practice guidelines. In addition, many tests have become available outside of genetics clinics through direct-to-consumer (DTC) companies and several offer tests not considered standard of care. To address several practical challenges associated with the rapid introduction of clinical and DTC genetic tests, we propose that genetic counselors and geneticists organize expert panels in their institutions to discuss the integration of new tests into patient care. We propose the establishment of Genetic Testing Integration Panels (GTIPs) to bring together local experts in medical genetics, genetic counseling, bioethics and law, health communication and clinical laboratory genetics. We describe key features of this approach and consider some of the potential advantages and limitations of using a GTIP to address the many clinical challenges raised by rapidly emerging clinical and DTC genetic tests. PMID:22246561

Challenges of CPAS Flight Testing

NASA Technical Reports Server (NTRS)

Ray, Eric S.; Morris, Aaron L.

2011-01-01

The Crew Exploration Vehicle Parachute Assembly System (CPAS) is being designed to land the Orion Crew Module (CM) at a safe rate of descent at splashdown via a series of Drogue, Pilot, and Main parachutes. Because Orion is considerably larger and heavier than Apollo, many of the flight test techniques developed during the Apollo program must be modified. The Apollo program had a dedicated C-133 aircraft, which was modified to allow a simple airdrop of "boilerplate" flight test vehicles. However, the CPAS program must use either commercial or military assets with minimal modifications to airframes or procedures. Conceptual envelopes from 2-Degree Of Freedom trajectories are presented for several existing and novel architectures. Ideally, the technique would deliver a representative capsule shape to the desired altitude and dynamic pressure at test initiation. However, compromises must be made on the characteristics of trajectories or the fidelity of test articles to production hardware. Most of the tests to date have used traditional pallet and weight tub or missile-shaped test vehicles. New test vehicles are being designed to better incorporate Orion structural components and deploy parachutes in a more representative fashion. The first attempt to test a capsule-shaped vehicle failed due to unexpected events while setting up the test condition through a series of complex procedures. In order to avoid the loss of another expensive test article which will delay the program, simpler deployment methods are being examined and more positive control of the vehicle will be maintained. Existing challenges include interfacing with parent aircraft, separating test vehicles, achieving test conditions, and landing within limited test ranges. All these challenges must be met within cost and schedule limits.

Selection of a discriminant and biorelevant in vitro dissolution test for the development of fenofibrate self-emulsifying lipid-based formulations.

PubMed

Pestieau, Aude; Krier, Fabrice; Brouwers, Adeline; Streel, Bruno; Evrard, Brigitte

2016-09-20

Fenofibrate, a BCS class II compound, has a low bioavailability especially when taken orally on an empty stomach. The challenge to find a new formulation for providing bioavailability, independent of food, is still ongoing. If the development of a suitable oral delivery formulation of BCS class II compounds is a frequent and great challenge to formulation scientists, the in vitro evaluation of these new formulations is also a great challenge. The purpose of this study was therefore to select an in vitro dissolution test that would be useful and as biorelevant as possible for the development of fenofibrate self-emulsifying lipid-based formulations. In this context, three different fenofibrate formulations, for which in vivo data are available in the literature, were tested using different dissolution tests until we found the one that was the most suitable. As part of this approach, we started with the simplest in vitro dissolution tests and progressed to tests that were increasingly more complex. The first tests were different single phase dissolution tests: a test under sink conditions based on the USP monograph, and different tests under non-sink conditions in non-biorelevant and biorelevant media. Given the inconclusive results obtained with these tests, biphasic dissolution systems were then tested: one with USP apparatus type II alone and another which combined USP apparatus types II and IV. This last combined test seemed the most suitable in vitro dissolution test for the development of the future fenofibrate lipid-based formulations we intend to develop in our own laboratory. Copyright © 2016 Elsevier B.V. All rights reserved.

Experimental PVC Material Challenge in Subjects with Occupational PVC Exposure

PubMed Central

Tuomainen, Anneli; Stark, Harri; Seuri, Markku; Hirvonen, Maija-Riitta; Linnainmaa, Markku; Sieppi, Anne; Tukiainen, Hannu

2006-01-01

Background Polyvinyl chloride (PVC) materials have been linked to asthma in several epidemiologic studies, but the possible causal factors remain unknown. Participants We challenged 10 subjects experimentally to degraded PVC products under controlled conditions. All of the subjects had previously experienced respiratory symptoms suspected to be caused by this kind of exposure in their work place. Five subjects had doctor-diagnosed asthma. Methods The subjects were exposed to degraded PVC material in an exposure chamber; a challenge with ceramic tile was used as the control test. We followed exhaled nitric oxide, nasal NO, lung functions, cytokines [tumor necrosis factor-α (TNF-α), interleukin-4 (IL-4), IL-6, and IL-12] and NO in nasal lavage fluid (NAL) during and after the exposures. We also measured 2-ethylhexanol in exhaled breath samples and NAL. Results On the morning after the PVC exposure, subjects reported respiratory tract symptoms significantly more often than they did after the control test (50% vs. 0%, respectively; p = 0.029; n = 10). We did not detect any changes in lung functions or levels of exhaled NO, nasal NO, or NO in NAL after PVC challenge compared with the control test. Cytokine levels increased after both exposures, with no statistically significant difference between situations. All of the exhaled breath samples collected during the PVC exposure contained 2-ethylhexanol. Conclusions PVC flooring challenge can evoke respiratory tract symptoms in exposed subjects. Our results do not support the hypothesis that PVC materials themselves evoke immediate asthmatic reactions. The chamber test used is well suited to this type of exposure study. PMID:16966097

Cognitive and Noncognitive Improvements Among ChalleNGe Cadets: A Survey of Seven Sites

DTIC Science & Technology

2016-06-01

Distribution unlimited Cognitive and Noncognitive Improvements Among ChalleNGe Cadets: A Survey of Seven Sites Lauren D. Malone and Jennifer R...completion and test score improvement. Using data on cadets’ scores on the Test of Adult Basic Education (TABE) and cadets’ responses to survey questions...total score. The sites also provided information on which cadets completed the program and cadets’ ages. In addition, we use data from a survey that

Education in Anti-Doping: The Art of Self-Imposed Constraints.

PubMed

Loland, Sigmund

2017-01-01

The pillars of anti-doping are detection, deterrence, and prevention. Detection takes the form of testing for banned substances. Deterrence builds on testing and gathering evidence. Athletes who test positive are exposed to penalties. The main tool of prevention is education. Education takes many forms and can be implemented in many ways. This chapter addresses the nature and challenges of current anti-doping education. Firstly, general goals of education and their connection to sport are discussed. Secondly, three normative interpretations of sport are presented, and their implications for anti-doping education are examined. Instrumentalist interpretations and interpretations with emphasis on performance and enhancement challenge the anti-doping campaign. A human excellence interpretation is advocated in which anti-doping is considered a consistent and integral part of sport. Thirdly, future challenges for anti-doping education are reflected upon. © 2017 S. Karger AG, Basel.

Barriers and Strategies Related to Qualitative Research on Genetic Ancestry Testing in Indigenous Communities.

PubMed

Blanchard, Jessica W; Tallbull, Gloria; Wolpert, Chantelle; Powell, Jill; Foster, Morris W; Royal, Charmaine

2017-07-01

Conducting genetics-related research with populations that have historically experienced considerable harm and little benefit from genetics research poses unique challenges for understanding community-based perceptions of new genetic technologies. This article identifies challenges and strategies for collecting qualitative data on the perceptions of direct-to-consumer (DTC) Genetic Ancestry tests (GAT) among diverse Indigenous communities. Based on a 3-year project related to perceptions, attitudes, and values associated with genetic ancestry testing among diverse Indigenous communities in Oklahoma, the engagement process revealed specific opportunities to improve the process of qualitative data collection related to GAT, and more broadly, to conduct genetics-related research with Indigenous communities in culturally and methodologically appropriate ways. Priority areas include issues related to participant recruitment and tribal advisory boards, challenges of self-identification as a recruitment mechanism, and the necessity of including Indigenous researchers in all aspects of the research process.

Space Environmental Effects Testing and Characterization of the Candidate Solar Sail Material Aluminized Mylar

NASA Technical Reports Server (NTRS)

Edwards, D. L.; Hubbs, W. S.; Wertz, G. E.; Alstatt, R.; Munafo, Paul (Technical Monitor)

2001-01-01

The usage of solar sails as a propellantless propulsion system has been proposed for many years. The technical challenges associated with solar sails are fabrication of ultralightweight films, deploying the sails and controlling the spacecraft. Integral to all these challenges is the mechanical property integrity of the sail while exposed to the harsh environment of space. This paper describes testing and characterization of a candidate solar sail material, Aluminized Mylar. This material was exposed to a simulated Geosynchronous Transfer Orbit (GTO) and evaluated by measuring thermooptical and mechanical property changes. Testing procedures and results are presented.

Radiation Testing, Characterization and Qualification Challenges for Modern Microelectronics and Photonics Devices and Technologies

NASA Technical Reports Server (NTRS)

LaBel, Kenneth A.; Cohn, Lewis M.

2008-01-01

At GOMAC 2007, we discussed a selection of the challenges for radiation testing of modern semiconductor devices focusing on state-of-the-art memory technologies. This included FLASH non-volatile memories (NVMs) and synchronous dynamic random access memories (SDRAMs). In this presentation, we extend this discussion in device packaging and complexity as well as single event upset (SEU) mechanisms using several technology areas as examples including: system-on-a-chip (SOC) devices and photonic or fiber optic systems. The underlying goal is intended to provoke thought for understanding the limitations and interpretation of radiation testing results.

Methotrexate Hypersensitivity Reactions in Pediatrics: Evaluation and Management

PubMed Central

Dilley, Meredith A.; Lee, Joyce P.; Broyles, Ana Dioun

2017-01-01

Reports of hypersensitivity reactions (HSRs) to MTX are limited to single case studies. We retrospectively reviewed HSRs to MTX during a 12-year period in our tertiary care pediatric center. Seven patients were evaluated for HSRs to MTX. Skin testing was positive in one of the 4 patients tested. One patient underwent successful graded challenge to MTX. Seventeen desensitizations to MTX were successfully performed in the other 6 patients. Skin testing, graded challenge, and desensitization were safe and effective procedures in the evaluation and management of patients with HSRs to MTX in our pediatric population. PMID:27786403

NASA Langley Distributed Propulsion VTOL Tilt-Wing Aircraft Testing, Modeling, Simulation, Control, and Flight Test Development

NASA Technical Reports Server (NTRS)

Rothhaar, Paul M.; Murphy, Patrick C.; Bacon, Barton J.; Gregory, Irene M.; Grauer, Jared A.; Busan, Ronald C.; Croom, Mark A.

2014-01-01

Control of complex Vertical Take-Off and Landing (VTOL) aircraft traversing from hovering to wing born flight mode and back poses notoriously difficult modeling, simulation, control, and flight-testing challenges. This paper provides an overview of the techniques and advances required to develop the GL-10 tilt-wing, tilt-tail, long endurance, VTOL aircraft control system. The GL-10 prototype's unusual and complex configuration requires application of state-of-the-art techniques and some significant advances in wind tunnel infrastructure automation, efficient Design Of Experiments (DOE) tunnel test techniques, modeling, multi-body equations of motion, multi-body actuator models, simulation, control algorithm design, and flight test avionics, testing, and analysis. The following compendium surveys key disciplines required to develop an effective control system for this challenging vehicle in this on-going effort.

Economic analysis of model validation for a challenge problem

DOE PAGES

Paez, Paul J.; Paez, Thomas L.; Hasselman, Timothy K.

2016-02-19

It is now commonplace for engineers to build mathematical models of the systems they are designing, building, or testing. And, it is nearly universally accepted that phenomenological models of physical systems must be validated prior to use for prediction in consequential scenarios. Yet, there are certain situations in which testing only or no testing and no modeling may be economically viable alternatives to modeling and its associated testing. This paper develops an economic framework within which benefit–cost can be evaluated for modeling and model validation relative to other options. The development is presented in terms of a challenge problem. Asmore » a result, we provide a numerical example that quantifies when modeling, calibration, and validation yield higher benefit–cost than a testing only or no modeling and no testing option.« less

Assemby, test, and launch operations for the Mars Exploration Rovers

NASA Technical Reports Server (NTRS)

Wallace, Matthew T.; Hardy, Paul V.; Romero, Raul A.; Salvo, Christopher G.; Shain, Thomas W.; Thompson, Arthur D.; Wirth, John W.

2005-01-01

In January of 2004, NASA's twin Mars rovers, Spirit and Opportunity, successfully landed on opposite sides of the Red Planet after a seven month Earth to Mars cruise period. Both vehicles have operated well beyond their 90 day primary mission design life requirements. The Assembly, Test, and Launch Operations (ATLO) program for these missions presented unique technical and schedule challenges to the team at the Jet Propulsion Laboratory (JPL). Among these challenges were a highly compressed schedule and late deliveries leading to extended double shift staffing, dual spacecraft operations requiring test program diversification and resource arbitration, multiple atypical test configurations for airbag/rocket landings and surface mobility testing, and verification of an exceptionally large number of separations, deployments, and mechanisms. This paper discusses the flight system test philosophies and approach, and presents lessons learned.

KSC-2009-6464

NASA Image and Video Library

2009-11-19

CAPE CANAVERAL, Fla. – This newly designed glove is one of the entries in the 2009 Astronaut Glove Challenge, part of NASA’s Centennial Challenges Program, at the Astronaut Hall of Fame near NASA’s Kennedy Space Center in Florida. The nationwide competition focused on developing improved pressure suit gloves for astronauts to use while working in space. During the challenge, inventors tested the gloves to measure dexterity and strength during operation in a glove box which simulates the vacuum of space. Centennial Challenges is NASA’s program of technology prizes for the citizen-inventor. The winning prize for the Glove Challenge is $250,000 provided by the Centennial Challenges Program. Photo credit: NASA/Kim Shiflett

Reusable Launch Vehicle Technology Program

NASA Technical Reports Server (NTRS)

Freeman, Delma C., Jr.; Talay, Theodore A.; Austin, R. Eugene

1996-01-01

Industry/NASA Reusable Launch Vehicle (RLV) Technology Program efforts are underway to design, test, and develop technologies and concepts for viable commercial launch systems that also satisfy national needs at acceptable recurring costs. Significant progress has been made in understanding the technical challenges of fully reusable launch systems and the accompanying management and operational approaches for achieving a low-cost program. This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33 and X-34 flight systems and associated technology programs. It addresses the specific technologies being tested that address the technical and operability challenges of reusable launch systems including reusable cryogenic propellant tanks, composite structures, thermal protection systems, improved propulsion, and subsystem operability enhancements. The recently concluded DC-XA test program demonstrated some of these technologies in ground and flight tests. Contracts were awarded recently for both the X-33 and X-34 flight demonstrator systems. The Orbital Sciences Corporation X-34 flight test vehicle will demonstrate an air-launched reusable vehicle capable of flight to speeds of Mach 8. The Lockheed-Martin X-33 flight test vehicle will expand the test envelope for critical technologies to flight speeds of Mach 15. A propulsion program to test the X-33 linear aerospike rocket engine using a NASA SR-71 high speed aircraft as a test bed is also discussed. The paper also describes the management and operational approaches that address the challenge of new cost-effective, reusable launch vehicle systems.

A new model for low-dose food challenge in children with allergy to milk or egg.

PubMed

Devenney, Irene; Norrman, Gunilla; Oldaeus, Göran; Strömberg, Leif; Fälth-Magnusson, Karin

2006-09-01

Atopic eczema and food allergy are common in early childhood. Children seem to gradually develop tolerance to milk and egg, and it is a relief for families when their child can tolerate small amounts of these basic foods, even if larger doses may still cause symptoms. To develop a model for low-dose oral food challenge, facilitating re-/introduction of milk or egg. In 39 children sensitized to milk and/or egg, we performed 52 challenges using a new standardized model for low-dose oral food challenge. The recipes were validated for blinding with sensorial tests. Four children challenged to milk had a positive challenge outcome. There were no significant differences with respect to family history, associated atopic manifestations, nutritional supply, eczema severity, or skin-prick test compared with the non-reacting children, but total and specific IgE values were significantly higher. All but two of the non-reacting children were able to introduce milk and egg into their diet without problems. We report recipes and a protocol to be used for standardized open and double-blind placebo-controlled low-dose food challenge in young children, enabling the introduction of small amounts of egg and milk into the diet during tolerance development.

Stability Testing of Herbal Drugs: Challenges, Regulatory Compliance and Perspectives.

PubMed

Bansal, Gulshan; Suthar, Nancy; Kaur, Jasmeen; Jain, Astha

2016-07-01

Stability testing is an important component of herbal drugs and products (HDPs) development process. Drugs regulatory agencies across the globe have recommended guidelines for the conduct of stability studies on HDPs, which require that stability data should be included in the product registration dossier. From the scientific viewpoint, numerous chemical constituents in an herbal drug are liable to varied chemical reactions under the influence of different conditions during its shelf life. These reactions can lead to altered chemical composition of HDP and consequently altered therapeutic profile. Many reports on stability testing of HDPs have appeared in literature since the last 10 years. A review of these reports reveals that there is wide variability in temperature (-80 to 100 °C), humidity (0-100%) and duration (a few hours-36 months) for stability assessment of HDPs. Of these, only 1% studies are conducted in compliance with the regulatory guidelines for stability testing. The present review is aimed at compiling all stability testing reports, understanding key challenges in stability testing of HDPs and suggesting possible solutions for these. The key challenges are classified as chemical complexity and biochemical composition variability in raw material, selection of marker(s) and influences of enzymes. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A computerized test battery for the assessment of cardiovascular reactivity.

PubMed

Debski, T T; Kamarck, T W; Jennings, J R; Young, L W; Eddy, M J; Zhang, Y X

1991-01-01

Recent evidence has suggested a possible relationship between the tendency to exhibit excessive cardiovascular reactions during psychological challenge and the risk of cardiovascular disease. Valid techniques for reliably assessing such reactions are, however, minimally available. A test battery for the assessment of cardiovascular reactivity to experimental challenge is currently being developed at the University of Pittsburgh in conjunction with the University of Miami and Duke University. An IBM-AT compatible microcomputer is being used for the concurrent collection of physiological data and presentation of the laboratory stressors. Digitized cardiovascular data being collected include EKG, Impedance Cardiogram (ICG), phonocardiogram, and a peripheral pulse wave measure. Blood pressure readings are also being collected and stored on disk. The computer presents three challenging video games, each designed to elicit cardiovascular reactions. Processing programs are being used and developed for the standardized scoring of the digitized signals. To assist in epidemiological research a mobile testing unit has been assembled for the easy administration of the test battery in varying geographical locations. The test battery being developed will increase the feasibility of epidemiological and clinical assessment of stress-induced cardiovascular responses which may substantiate a link between reactivity and cardiovascular disease.

A risk index for pediatric patients undergoing diagnostic imaging with 99mTc-dimercaptosuccinic acid that accounts for body habitus

NASA Astrophysics Data System (ADS)

O'Reilly, Shannon E.; Plyku, Donika; Sgouros, George; Fahey, Frederic H.; Treves, S. Ted; Frey, Eric C.; Bolch, Wesley E.

2016-03-01

Published guidelines for administered activity to pediatric patients undergoing diagnostic nuclear medicine imaging are currently obtained through expert consensus of the minimum values as a function of body weight as required to yield diagnostic quality images. We have previously shown that consideration of body habitus is also important in obtaining diagnostic quality images at the lowest administered activity. The objective of this study was to create a series of computational phantoms that realistically portray the anatomy of the pediatric patient population which can be used to develop and validate techniques to minimize radiation dose while maintaining adequate image quality. To achieve this objective, we have defined an imaging risk index that may be used in future studies to develop pediatric patient dosing guidelines. A population of 48 hybrid phantoms consisting of non-uniform B-spline surfaces and polygon meshes was generated. The representative ages included the newborn, 1 year, 5 year, 10 year and 15 year male and female. For each age, the phantoms were modeled at their 10th, 50th, and 90th height percentile each at a constant 50th weight percentile. To test the impact of kidney size, the newborn phantoms were modeled with the following three kidney volumes:  -15%, average, and  +15%. To illustrate the impact of different morphologies on dose optimization, we calculated the effective dose for each phantom using weight-based 99mTc-DMSA activity administration. For a given patient weight, body habitus had a considerable effect on effective dose. Substantial variations were observed in the risk index between the 10th and 90th percentile height phantoms from the 50th percentile phantoms for a given age, with the greatest difference being 18%. There was a dependence found between kidney size and risk of radiation induced kidney cancer, with the highest risk indices observed in newborns with the smallest kidneys. Overall, the phantoms and techniques in this study can be used to provide data to refine dosing guidelines for pediatric nuclear imaging studies while taking into account the effects on both radiation dose and image quality. This work was supported by:R01 EB013558 with the National Institute for Biomedical Imaging and Bioengineering (NIBIB).

Laboratory considerations of United States Pharmacopeia Chapter <71> sterility tests and its application to pharmaceutical compounding.

PubMed

Hyde, Tiffany D

2014-01-01

The purpose of this article is to describe United States Pharmacopeia Chapter <71> Sterility Tests from the perspective of Current Good Manufacturing Practices in order to aid compounding pharmacists in understanding the details and complexities that are required. Compounding pharmacists face a unique challenge in the industry today, with their compounding practice and the U.S. Food and Drug Administration trying to impose Current Good Manufacturing Practices guidelines. Naturally, this becomes a challenge to contract testing laboratories as well, as they are caught between the testing for non-Current Good Manufacturing Practices compounding standards and Current Good Manufacturing Practices manufacturing. It is important that the compounding pharmacist and their partner testing laboratory work closely together to ensure appropriate requirements are being met.

Staff in Services for People with Intellectual Disabilities: The Impact of Stress on Attributions of Challenging Behaviour

ERIC Educational Resources Information Center

Rose, D.; Rose, J.

2005-01-01

Background: There is a lack of a conceptual framework as to how stress and attribution variables interact and influence staff behaviour in response to challenging behaviour. To address this, a model is tested examining the impact of stress on attributions of challenging behaviour within Weiner's model of helping. Method: A total of 107 staff…

Oral glutamine challenge and magnetic resonance spectroscopy in three patients with congenital portosystemic shunts.

PubMed

Ortiz, María; Córdoba, Juan; Alonso, Juli; Rovira, Alex; Quiroga, Sergi; Jacas, Carlos; Esteban, Rafael; Guardia, Jaume

2004-03-01

Congenital portosystemic shunts are rare abnormalities of liver vasculature that can cause neurological symptoms, probably secondarily to the effects of the metabolism of ammonia in the brain. Our aim was to investigate the relationship between capillary blood ammonia after oral glutamine challenge and magnetic resonance spectroscopy in three patients with congenital portosystemic shunts. Neuropsychological tests, oral glutamine challenge and magnetic resonance spectroscopy were performed at baseline and after 6 months of follow-up in three patients with congenital portosystemic shunts. The results were compared to those obtained in a group of six cirrhotic patients with prior episodes of hepatic encephalopathy and healthy controls. Patients with congenital portosystemic shunts exhibited abnormalities of neuropsychological tests, magnetic resonance spectroscopy and a response to the oral glutamine challenge similar to those observed in patients with cirrhosis. The intensity of the rise of brain glutamine was correlated to the area under the curve of ammonia after the oral glutamine challenge (R=0.72). Neurological manifestations of patients with congenital portosystemic shunts are mediated through similar mechanisms that are involved in the pathogenesis of hepatic encephalopathy. The area under the curve appears to be the better parameter that defines the response to the oral glutamine challenge.

Effectiveness of touch and feel (TAF) technique on first aid measures for visually challenged.

PubMed

Mary, Helen; Sasikalaz, D; Venkatesan, Latha

2013-01-01

There is a common perception that a blind person cannot even help his own self. In order to challenge that view, a workshop for visually-impaired people to develop the skills to be independent and productive members of society was conceived. An experimental study was conducted at National Institute of Visually Handicapped, Chennai with the objective to assess the effectiveness of Touch and Feel (TAF) technique on first aid measures for the visually challenged. Total 25 visually challenged people were selected by non-probability purposive sampling technique and data was collected using demographic variable and structured knowledge questionnaire. The score obtained was categorised into three levels: inadequate (0-8), moderately adequate (8 - 17), adequate (17 -25). The study revealed that most of the visually challenged (40%) had inadequate knowledge, and 56 percent had moderately adequate and only few (4%) had adequate knowledge in the pre-test, whereas most (68%) of them had adequate knowledge in the post-test which is statistically significant at p < 0.000 with t-value 6.779. This proves that TAF technique was effective for the visually challenged. There was no association between the demographic variables and their level of knowledge regarding first aid.

Limited accessibility to HIV services for persons with disabilities living with HIV in Ghana, Uganda and Zambia.

PubMed

Tun, Waimar; Okal, Jerry; Schenk, Katie; Esantsi, Selina; Mutale, Felix; Kyeremaa, Rita Kusi; Ngirabakunzi, Edson; Asiah, Hilary; McClain-Nhlapo, Charlotte; Moono, Grimond

2016-01-01

Knowledge about experiences in accessing HIV services among persons with disabilities who are living with HIV in sub-Saharan Africa is limited. Although HIV transmission among persons with disabilities in Africa is increasingly acknowledged, there is a need to bring to life the experiences and voices from persons with disabilities living with HIV to raise awareness of programme implementers and policy makers about their barriers in accessing HIV services. This paper explores how the barriers faced by persons with disabilities living with HIV impede their ability to access HIV-related services and manage their disease. We conducted focus group discussions with 76 persons (41 females; 35 males) with physical, visual and/or hearing impairments who were living with HIV in Ghana, Uganda and Zambia (2012-2013). We explored challenges and facilitators at different levels (individual, psychosocial and structural) of access to HIV services. Transcripts were analyzed using a framework analysis approach. Persons with disabilities living with HIV encountered a wide variety of challenges in accessing HIV services. Delays in testing for HIV were common, with most waiting until they were sick to be tested. Reasons for delayed testing included challenges in getting to the health facilities, lack of information about HIV and testing, and HIV- and disability-related stigma. Barriers to HIV-related services, including care and treatment, at health facilities included lack of disability-friendly educational materials and sign interpreters, stigmatizing treatment by providers and other patients, lack of skills to provide tailored services to persons with disabilities living with HIV and physically inaccessible infrastructure, all of which make it extremely difficult for persons with disabilities to initiate and adhere to HIV treatment. Accessibility challenges were greater for women than men due to gender-related roles. Challenges were similar across the three countries. Favourable experiences in accessing HIV services were reported in Uganda and Zambia, where disability-tailored services were offered by non-governmental organizations and government facilities (Uganda only). Persons with disabilities living with HIV encounter many challenges in accessing HIV testing and continued care and treatment services. Changes are needed at every level to ensure accessibility of HIV services for persons with disabilities.

The diagnostic value of component-resolved diagnostics in peanut allergy in children attending a Regional Paediatric Allergology Clinic.

PubMed

van Veen, Leonieke N; Heron, Michiel; Batstra, Manou; van Haard, Paul M M; de Groot, Hans

2016-06-02

To date, diagnosing food allergies in children still presents a diagnostic dilemma, leading to uncertainty concerning the definite diagnosis of peanut allergy, as well as to the need for strict diets and the potential need for adrenalin auto-injectors. This uncertainty in particular is thought to contribute to a lower quality of life. In the diagnostic process double-blind food challenges are considered the gold standard, but they are time-consuming as well as potentially hazardous. Other diagnostic tests have been extensively studied and among these component-resolved diagnostics appeared to present a promising alternative: Ara h2, a peanut storage protein in previous studies showed to have a significant predictive value. Sixty-two out of 72 children, with suspected peanut allergy were analyzed using serum specific IgE and/or skin prick tests and specific IgE to several components of peanut (Ara h 1, 2, 3, 6, 8, 9). Subsequently, double-blind food challenges were performed. The correlation between the various diagnostic tests and the overall outcome of the double-blind food challenges were studied, in particular the severity of the reaction and the eliciting dose. The double-blind provocation with peanut was positive in 33 children (53 %). There was no relationship between the eliciting dose and the severity of the reaction. A statistically significant relationship was found between the skin prick test, specific IgE directed to peanut, Ara h 1, Ara h 2 or Ara h 6, and the outcome of the food challenge test, in terms of positive or negative (P < .001). However, we did not find any relationship between sensitisation to peanut extract or the different allergen components and the severity of the reaction or the eliciting dose. There was no correlation between IgE directed to Ara h 3, Ara h 8, Ara h 9 and the clinical outcome of the food challenge. This study shows that component-resolved diagnostics is not superior to specific IgE to peanut extract or to skin prick testing. At present, it cannot replace double-blind placebo-controlled food challenges for determination of the eliciting dose or the severity of the peanut allergy in our patient group.

Challenges for achieving safe and effective radical cure of Plasmodium vivax: a round table discussion of the APMEN Vivax Working Group.

PubMed

Thriemer, Kamala; Ley, Benedikt; Bobogare, Albino; Dysoley, Lek; Alam, Mohammad Shafiul; Pasaribu, Ayodhia P; Sattabongkot, Jetsumon; Jambert, Elodie; Domingo, Gonzalo J; Commons, Robert; Auburn, Sarah; Marfurt, Jutta; Devine, Angela; Aktaruzzaman, Mohammad M; Sohel, Nayeem; Namgay, Rinzin; Drukpa, Tobgyel; Sharma, Surender Nath; Sarawati, Elvieda; Samad, Iriani; Theodora, Minerva; Nambanya, Simone; Ounekham, Sonesay; Mudin, Rose Nanti Binti; Da Thakur, Garib; Makita, Leo Sora; Deray, Raffy; Lee, Sang-Eun; Boaz, Leonard; Danansuriya, Manjula N; Mudiyanselage, Santha D; Chinanonwait, Nipon; Kitchakarn, Suravadee; Nausien, Johnny; Naket, Esau; Duc, Thang Ngo; Do Manh, Ha; Hong, Young S; Cheng, Qin; Richards, Jack S; Kusriastuti, Rita; Satyagraha, Ari; Noviyanti, Rintis; Ding, Xavier C; Khan, Wasif Ali; Swe Phru, Ching; Guoding, Zhu; Qi, Gao; Kaneko, Akira; Miotto, Olivo; Nguitragool, Wang; Roobsoong, Wanlapa; Battle, Katherine; Howes, Rosalind E; Roca-Feltrer, Arantxa; Duparc, Stephan; Bhowmick, Ipsita Pal; Kenangalem, Enny; Bibit, Jo-Anne; Barry, Alyssa; Sintasath, David; Abeyasinghe, Rabindra; Sibley, Carol H; McCarthy, James; von Seidlein, Lorenz; Baird, J Kevin; Price, Ric N

2017-04-05

The delivery of safe and effective radical cure for Plasmodium vivax is one of the greatest challenges for achieving malaria elimination from the Asia-Pacific by 2030. During the annual meeting of the Asia Pacific Malaria Elimination Network Vivax Working Group in October 2016, a round table discussion was held to discuss the programmatic issues hindering the widespread use of primaquine (PQ) radical cure. Participants included 73 representatives from 16 partner countries and 33 institutional partners and other research institutes. In this meeting report, the key discussion points are presented and grouped into five themes: (i) current barriers for glucose-6-phosphate deficiency (G6PD) testing prior to PQ radical cure, (ii) necessary properties of G6PD tests for wide scale deployment, (iii) the promotion of G6PD testing, (iv) improving adherence to PQ regimens and (v) the challenges for future tafenoquine (TQ) roll out. Robust point of care (PoC) G6PD tests are needed, which are suitable and cost-effective for clinical settings with limited infrastructure. An affordable and competitive test price is needed, accompanied by sustainable funding for the product with appropriate training of healthcare staff, and robust quality control and assurance processes. In the absence of quantitative PoC G6PD tests, G6PD status can be gauged with qualitative diagnostics, however none of the available tests is currently sensitive enough to guide TQ treatment. TQ introduction will require overcoming additional challenges including the management of severely and intermediately G6PD deficient individuals. Robust strategies are needed to ensure that effective treatment practices can be deployed widely, and these should ensure that the caveats are outweighed by  the benefits of radical cure for both the patients and the community. Widespread access to quality controlled G6PD testing will be critical.

Top ten challenges when interfacing a laboratory information system to an electronic health record: Experience at a large academic medical center.

PubMed

Petrides, Athena K; Tanasijevic, Milenko J; Goonan, Ellen M; Landman, Adam B; Kantartjis, Michalis; Bates, David W; Melanson, Stacy E F

2017-10-01

Recent U.S. government regulations incentivize implementation of an electronic health record (EHR) with computerized order entry and structured results display. Many institutions have also chosen to interface their EHR to their laboratory information system (LIS). Reported long-term benefits include increased efficiency and improved quality and safety. In order to successfully implement an interfaced EHR-LIS, institutions must plan years in advance and anticipate the impact of an integrated system. It can be challenging to fully understand the technical, workflow and resource aspects and adequately prepare for a potentially protracted system implementation and the subsequent stabilization. We describe the top ten challenges that we encountered in our clinical laboratories following the implementation of an interfaced EHR-LIS and offer suggestions on how to overcome these challenges. This study was performed at a 777-bed, tertiary care center which recently implemented an interfaced EHR-LIS. Challenges were recorded during EHR-LIS implementation and stabilization and the authors describe the top ten. Our top ten challenges were selection and harmonization of test codes, detailed training for providers on test ordering, communication with EHR provider champions during the build process, fluid orders and collections, supporting specialized workflows, sufficient reports and metrics, increased volume of inpatient venipunctures, adequate resources during stabilization, unanticipated changes to laboratory workflow and ordering specimens for anatomic pathology. A few suggestions to overcome these challenges include regular meetings with clinical champions, advanced considerations of reports and metrics that will be needed, adequate training of laboratory staff on new workflows in the EHR and defining all tests including anatomic pathology in the LIS. EHR-LIS implementations have many challenges requiring institutions to adapt and develop new infrastructures. This article should be helpful to other institutions facing or undergoing a similar endeavor. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of contamination rates between preserved and preservative-free fluoroquinolone eyedrops.

PubMed

Kim, Mo Sae; Kim, Hong Kyun; Kim, Joon Mo; Choi, Chul Young

2013-03-01

To evaluate the antimicrobial effectiveness of preservative-free fluoroquinolone products compared with benzalkonium chloride containing fluoroquinolones using the challenge test provided by the United States Pharmacopeia (USP) and the in-use test. 1. Challenge test: to compare the growth of microorganisms between different fluoroquinolone preparations, four test organisms, including Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger were chosen among five microorganisms listed by USP 2004. The inoculated products were sampled for microbial survivors at days 7, 14, and 28 following initial inoculation at room temperature. The number of surviving organisms were calculated as a Log10 reduction from the original inocula. 2. In-use test: a total of 100 bottles were collected after instillation of preservative-free fluoroquinolone eyedrops in volunteer patients after 1 week of use. The remaining fluid and tips of the bottles were cultured. Colonies on the plates were counted at the end of the incubation period. All microorganisms were identified by Gram staining and biochemical assays. 1. Challenge test: preservative-free gatifloxacin and levofloxacin demonstrated a lower log reduction against A. niger than preserved fluoroquinolones and preservative-free moxifloxacin at all time points. 2. In-use test: There was no contamination identified on plates inoculated by preservative-free quinolone bottles after 1 week of use in this study. Physicians should be aware of the lower antifungal preservative effectiveness of some preservative-free fluoroquinolone preparations than preserved ones.

Jensen's Last Stand.

ERIC Educational Resources Information Center

Gould, Stephen Jay

1980-01-01

Challenges Jensen's arguments (set forth in the book "Bias in Mental Testing") that intelligence tests are scientifically unbiased and that IQ and other mental tests measure something called "intelligence" by refuting Jensen's reading of the psychometric research literature. (EF)

The Tests and the "Brightest." How Fair Are the College Boards?

ERIC Educational Resources Information Center

Fallows, James

1980-01-01

The role of standardized tests in American education is being challenged as many feel that they are unfair and actually reinforce and legitimize existing inequalities. The Educational Testing Service, the SAT, meritocracy, test coaching, and economic bias are discussed. (MLW)

40 CFR 141.719 - Additional filtration toolbox components.

Code of Federal Regulations, 2013 CFR

2013-07-01

... establish a quality control release value (QCRV) for a non-destructive performance test that demonstrates... test; and Cp = the filtrate concentration measured during the challenge test. Equivalent units must be... or the applicability of the non-destructive performance test and associated QCRV, additional...

40 CFR 141.719 - Additional filtration toolbox components.

Code of Federal Regulations, 2014 CFR

2014-07-01

... establish a quality control release value (QCRV) for a non-destructive performance test that demonstrates... test; and Cp = the filtrate concentration measured during the challenge test. Equivalent units must be... or the applicability of the non-destructive performance test and associated QCRV, additional...

40 CFR 141.719 - Additional filtration toolbox components.

Code of Federal Regulations, 2012 CFR

2012-07-01

... establish a quality control release value (QCRV) for a non-destructive performance test that demonstrates... test; and Cp = the filtrate concentration measured during the challenge test. Equivalent units must be... or the applicability of the non-destructive performance test and associated QCRV, additional...

Truth in Testing: Arguments Examined.

ERIC Educational Resources Information Center

Burns, Daniel J.

1981-01-01

Costs and benefits of New York's Truth-in-Testing law are reviewed and related to constitutional issues and fairness to test-makers as well as test-takers. Besides matters of cost and test question availability, challenges to the legislation also involve issues of due process, equal protection, and infringement of existing copyright laws. (MSE)

Word Families and Frequency Bands in Vocabulary Tests: Challenging Conventions

ERIC Educational Resources Information Center

Kremmel, Benjamin

2016-01-01

Vocabulary test development often appears to be based on the design principles of previous tests, without questioning or empirically examining the assumptions underlying those principles. Given the current proliferation of vocabulary tests, it seems timely for the field of vocabulary testing to problematize some of those traditionalised…

The Drug Testing of College Athletes.

ERIC Educational Resources Information Center

Leeson, Todd A.

1989-01-01

The paper examines the state of drug testing of college athletes and the challenges faced by the National Collegiate Athletic Association and university testing programs. State and federal litigation on drug testing is reviewed along with other issues in the drug-testing debate. Practical recommendations are offered to educational institutions.…

Preventive effect of a high fluoride toothpaste and arginine-carbonate toothpaste on dentinal tubules exposure followed by acid challenge: a dentine permeability evaluation

PubMed Central

2014-01-01

Background Considering the current high use of high fluoride toothpastes, the aim of the study was to quantify alterations in the root dentine permeability submitted to treatment with a high fluoride toothpaste and 8% arginine, calcium carbonate, sodium monofluorophosphate toothpaste as a preventive treatment for dentinal tubules exposure followed by acid challenge. Methods Thirty-third molars were sectioned below the cementoenamel. The root segments were connected to a hydraulic pressure apparatus to measure dentine permeability after the following sequential steps (n = 10 per group): I) Baseline; II) treatment with phosphoric acid for 30 s (maximum permeability); III) Toothbrushing (1 min) according to the experimental groups (G1- control; G2- 5000 ppm fluoride toothpaste; G3- 8% arginine-calcium carbonate toothpaste); IV) acid challenge for 5 min (orange juice). The data were converted into percentage, considering stage II as 100%. Results The results have shown a statistically significant decreasing on dentine permeability after treatment with toothpaste (Friedman test and Dunn’s post hoc test). Comparison among groups demonstrated a high increasing on dentine permeability when acid challenge was performed after toothbrushing with distilled water (control group) (Kruskal-Wallis and Dunn’s post hoc test). Conclusion The toothpaste treatment may provide sufficient resistance on dentine surface, preventing dentinal tubules exposure after acid challenge. PMID:24958423

D3R Grand Challenge 2: blind prediction of protein-ligand poses, affinity rankings, and relative binding free energies

NASA Astrophysics Data System (ADS)

Gaieb, Zied; Liu, Shuai; Gathiaka, Symon; Chiu, Michael; Yang, Huanwang; Shao, Chenghua; Feher, Victoria A.; Walters, W. Patrick; Kuhn, Bernd; Rudolph, Markus G.; Burley, Stephen K.; Gilson, Michael K.; Amaro, Rommie E.

2018-01-01

The Drug Design Data Resource (D3R) ran Grand Challenge 2 (GC2) from September 2016 through February 2017. This challenge was based on a dataset of structures and affinities for the nuclear receptor farnesoid X receptor (FXR), contributed by F. Hoffmann-La Roche. The dataset contained 102 IC50 values, spanning six orders of magnitude, and 36 high-resolution co-crystal structures with representatives of four major ligand classes. Strong global participation was evident, with 49 participants submitting 262 prediction submission packages in total. Procedurally, GC2 mimicked Grand Challenge 2015 (GC2015), with a Stage 1 subchallenge testing ligand pose prediction methods and ranking and scoring methods, and a Stage 2 subchallenge testing only ligand ranking and scoring methods after the release of all blinded co-crystal structures. Two smaller curated sets of 18 and 15 ligands were developed to test alchemical free energy methods. This overview summarizes all aspects of GC2, including the dataset details, challenge procedures, and participant results. We also consider implications for progress in the field, while highlighting methodological areas that merit continued development. Similar to GC2015, the outcome of GC2 underscores the pressing need for methods development in pose prediction, particularly for ligand scaffolds not currently represented in the Protein Data Bank (http://www.pdb.org), and in affinity ranking and scoring of bound ligands.

In vitro testing to diagnose venom allergy and monitor immunotherapy: a placebo-controlled, crossover trial.

PubMed

Brown, S G A; Haas, M A; Black, J A; Parameswaran, A; Woods, G M; Heddle, R J

2004-05-01

In people with a history of sting allergy, only prior reaction severity and older age are known to predict subsequent reaction risk. Furthermore, no diagnostic test other than a deliberate sting challenge has been found to identify people in whom venom immunotherapy (VIT) has been unsuccessful. We aimed to assess the utility of a number of in vitro tests to diagnose venom allergy and to monitor immunotherapy. During a double-blind randomized placebo-controlled crossover trial of Myrmecia pilosula ant VIT the following venom-specific tests were performed at enrolment, and at completion of treatment prior to a diagnostic sting challenge; leucocyte stimulation index (SI), IL-4 production, IgE RAST, histamine release test (HRT), leukotriene release test (LRT) and basophil activation test (BAT). Intradermal venom skin testing (VST) was also performed at trial entry. Only VST and HRT identified those at risk of sting anaphylaxis in the placebo group. Although IgE RAST, leucocyte SI and IL-4 production, LRT and BAT all correlated well with intradermal VSTs, they did not predict sting challenge outcome. After successful VIT, venom-induced leucocyte IL-4 production tended to fall, whereas IgE RAST increased and a natural decline in HRT reactivity was reversed. A confounding seasonal affect on laboratory results was suspected. The HRT warrants further assessment for diagnosis of venom allergy. Uninformative performance of the commercially available LRT and BAT tests may be due to pre-incubation with IL-3. None of the tests evaluated appear to be reliable markers of successful VIT.

Direct to consumer genetic testing-law and policy concerns in Ireland.

PubMed

de Paor, Aisling

2017-11-25

With rapid scientific and technological advances, the past few years has witnessed the emergence of a new genetic era and a growing understanding of the genetic make-up of human beings. These advances have propelled the introduction of companies offering direct to consumer (DTC) genetic testing, which facilitates the direct provision of such tests to consumers, (for example, via the internet). Although DTC genetic testing offers benefits by enhancing consumer accessibility to such technology, promoting proactive healthcare and increasing genetic awareness, it presents a myriad of challenges, from an ethical, legal and regulatory perspective. As DTC genetic testing usually eliminates the need for a medical professional in accessing genetic tests, this lack of professional guidance and counselling may result in misinterpretation and confusion regarding results. In addition, an evident concern relates to the scientific validity and quality of these tests. A further problem arising is the lack or inadequacy of regulation in this field. Despite the increasing accessibility of DTC genetic testing, this legislative vacuum is apparent in Ireland, where there is no concrete legislation. This article explores the main ethical, legal and regulatory issues arising with the advent of rapid advances in DTC genetic testing in Ireland. Further, with inevitable future advances in genetic science, as well as increasing internet accessibility, the challenges presented are likely to become more amplified. In consideration of the ethical and legal challenges, this paper highlights the regulation of DTC genetic testing as a growing concern in Ireland, recognising its importance to both the scientific community as well as in respect of enhancing consumer confidence in such technologies.

Quantitative genetics of taura syndrome resistance in pacific white shrimp (penaeus vannamei): a cure model approach

PubMed Central

2011-01-01

Background In aquaculture breeding, resistance against infectious diseases is commonly assessed as time until death under exposure to a pathogen. For some diseases, a fraction of the individuals may appear as "cured" (non-susceptible), and the resulting survival time may thus be a result of two confounded underlying traits, i.e., endurance (individual hazard) and susceptibility (whether at risk or not), which may be accounted for by fitting a cure survival model. We applied a cure model to survival data of Pacific white shrimp (Penaeus vannamei) challenged with the Taura syndrome virus, which is one of the major pathogens of Panaeid shrimp species. Methods In total, 15,261 individuals of 513 full-sib families from three generations were challenge-tested in 21 separate tests (tanks). All challenge-tests were run until mortality naturally ceased. Time-until-event data were analyzed with a mixed cure survival model using Gibbs sampling, treating susceptibility and endurance as separate genetic traits. Results Overall mortality at the end of test was 28%, while 38% of the population was considered susceptible to the disease. The estimated underlying heritability was high for susceptibility (0.41 ± 0.07), but low for endurance (0.07 ± 0.03). Furthermore, endurance and susceptibility were distinct genetic traits (rg = 0.22 ± 0.25). Estimated breeding values for endurance and susceptibility were only moderately correlated (0.50), while estimated breeding values from classical models for analysis of challenge-test survival (ignoring the cured fraction) were closely correlated with estimated breeding values for susceptibility, but less correlated with estimated breeding values for endurance. Conclusions For Taura syndrome resistance, endurance and susceptibility are apparently distinct genetic traits. However, genetic evaluation of susceptibility based on the cure model showed clear associations with standard genetic evaluations that ignore the cure fraction for these data. Using the current testing design, genetic variation in observed survival time and absolute survival at the end of test were most likely dominated by genetic variation in susceptibility. If the aim is to reduce susceptibility, earlier termination of the challenge-test or back-truncation of the follow-up period should be avoided, as this may shift focus of selection towards endurance rather than susceptibility. PMID:21418636

Passive Thermal Control Challenges for Future Exploration Missions

NASA Technical Reports Server (NTRS)

Rickman, Steven L.

2004-01-01

This slide presentation reviews the importance of developing passive thermal control for the future exploration missions envisioned in President Bush's call for human exploration of the Moon and Mars. Included in the presentation is a review of the conditions that make the thermal control very challenging on the Moon and Mars. With the future miniaturization of electronics components, power density and the associated challenges of electronics heat dissipation will provide new challenges. There is a challenge for improvement in modeling and analysis of thermal control systems, and for improved facilities to support testing of thermal-vacuum systems.

Towards the Experimental Assessment of the DQE in SPECT Scanners

NASA Astrophysics Data System (ADS)

Fountos, G. P.; Michail, C. M.

2017-11-01

The purpose of this work was to introduce the Detective Quantum Efficiency (DQE) in single photon emission computed tomography (SPECT) systems using a flood source. A Tc-99m-based flood source (Eγ = 140 keV) consisting of a radiopharmaceutical solution of dithiothreitol (DTT, 10-3 M)/Tc-99m(III)-DMSA, 40 mCi/40 ml bound to the grains of an Agfa MammoRay HDR Medical X-ray film) was prepared in laboratory. The source was placed between two PMMA blocks and images were obtained by using the brain tomographic acquisition protocol (DatScan-brain). The Modulation Transfer Function (MTF) was evaluated using the Iterative 2D algorithm. All imaging experiments were performed in a Siemens e-Cam gamma camera. The Normalized Noise Power spectra (NNPS) were obtained from the sagittal views of the source. The higher MTF values were obtained for the Flash Iterative 2D with 24 iterations and 20 subsets. The noise levels of the SPECT reconstructed images, in terms of the NNPS, were found to increase as the number of iterations increase. The behavior of the DQE was influenced by both MTF and NNPS. As the number of iterations was increased, higher MTF values were obtained, however with a parallel, increase of magnitude in image noise, as depicted from the NNPS results. DQE values, which were influenced by both MTF and NNPS, were found higher when the number of iterations results in resolution saturation. The method presented here is novel and easy to implement, requiring materials commonly found in clinical practice and can be useful in the quality control of SPECT scanners.

Evaluation of abnormal radiological findings in children aged 2 to 36 months followed by recurrent urinary tract infection: a retrospective study.

PubMed

Ozen, Cinar; Ertan, Pelin; Aras, Feray; Gumuser, Gul; Ozkol, Mine; Horasan Dinc, Gonul

2017-11-01

Our aim is to determine the rational usage of imaging techniques in order to prevent or minimize permanent renal damage in recurrent urinary tract infections (UTIs). This study was enrolled children aged between 2 and 36 months, following-up with the diagnosis of recurrent UTI. All children had ultrasonography (USG) and dimercaptosuccinic acid scanning, 39 of them had underwent on voiding cystourethrography. There were 133 children (87 girls, 46 boys) with the mean age of 32.82 ± 38.10 months included into the study. Forty-three kidney units were normal in ultrasonogram of which seven units had reflux whereas among 35 units with hydronephrosis 22 units had reflux. Sensitivity and specificity presence of hydronephrosis in ultrasonogram for prediction of reflux was 75.9% and 73.5%, respectively. There were 19 dilated ureters in ultrasonogram, and among them 14 had reflux. Sensitivity and specificity of presence with ureteral dilatation in ultrasonogram for prediction of reflux was found as 48.3% and 89.8%, respectively. The sensitivity of parenchymal thinning seen in ultrasonogram for the evaluation of renal parenchyma was 15.9%, whereas specificity was 98.2% .Sensitivity and specificity of dimercaptosuccinic acid for prediction of reflux was 51.6% and 72.3%, respectively. The normal ultrasonogram findings cannot rule out neither possibility of reflux presence nor development of renal scarring. Therefore, DMSA scanning has major role both in determination of parenchymal damage and prevention of scarring. Also we get an important result as ureteral dilatation seen in USG, related to presence of reflux.

Testing Methods for Challenging the National Wetland Plant List: Using Tsuga canadensis (L.) Carr. (Eastern Hemlock) as a Case Study

DTIC Science & Technology

2017-07-01

ESRI (Nature Conservancy and Environmental Systems Research Institute). 1994. Field Methods . In Field Methods for Vegetation Mapping: United States...ER D C/ CR RE L TR -1 7- 9 Wetlands Regulatory Assistance Program (WRAP) Testing Methods for Challenging the National Wetland Plant List...Robert W. Lichvar and Jennifer J. Goulet July 2017 Approved for public release; distribution is unlimited. The U.S. Army Engineer Research

[Occupational allergic "march". Rapid evolution of contact dermatitis to ammonium persulfate into airborne contact dermatitis with rhinitis and asthma in a hairdresser].

PubMed

Poltronieri, Anna; Patrini, L; Pigatto, P; Riboldi, L; Marsili, Chiara; Previdi, M; Margonari, M; Marraccini, P

2010-01-01

Hairdressers are exposed to irritants and allergenic compounds that may cause contact dermatitis, rhinitis and asthma. In this paper we describe the case of a female, age 33 years, who developed contact dermatitis after 10 years of exposure to ammonium persulfate. After 7 months of progressively extensive and persistent skin lesions, respiratory symptoms appeared that were related to the occupational exposure (on-off test). SIDAPA and specific occupational patch test for hairdressers and occupational challenge with ammonium persulfate were performed. Clinical parameters of inflammation, ECP (eosinophil cationic protein) and exhaled nitric oxide (FeNO) were detected before and after the specific bronchial challenge. The patch test was positive to ammonium persulfate (++), and bronchial challenge for ammonium persulfate showed a significant late response (FEV1 decrease--33%). Both FeNO and ECP showed a significant increase after 24 hours. Dermatitis, urticaria and angioedema occurred on the uncovered skin due to airborne contact. Topic steroids and anti-histaminic drugs resolved the clinical symptoms. Bronchial challenge is, in fact, considered to be the gold standard for the diagnosis of occupational asthma, although new inflammatory parameters can contribute to the diagnosis and can be useful for monitoring after a specific inhalation test with occupational agents. The described case summarizes the evolution from contact dermatitis to inhalation allergy, suggesting the occurrence of an allergic "march" for occupational allergy.

Secretory IgA as an indicator of oro-pharyngeal foot-and-mouth disease virus replication and as a tool for post vaccination surveillance.

PubMed

Parida, Satya; Anderson, John; Cox, Sarah J; Barnett, Paul V; Paton, David J

2006-02-20

A serotype-specific ELISA was developed to detect foot-and-mouth disease virus (FMDV) specific IgA antibody in the saliva of cattle, and the method was evaluated for its feasibility in detecting serotype O FMDV carrier animals, particularly amongst vaccinated cattle that had subsequently become sub-clinically infected. For this purpose, saliva samples were collected from naïve cattle (n = 173), FMDV challenged cattle (n = 10), FMDV vaccinated cattle (n = 40) and FMDV vaccinated-and-challenged cattle (n = 40). A subset of 29 cattle was sampled for 105-168 days after challenge. The FMDV infection status of each of the cattle was determined by virus isolation and RT-PCR tests on oesophago-pharyngeal fluids and the ability of the IgA test to detect viral infection and persistence was compared to an ELISA for the detection of serum antibodies against the 3ABC non-structural proteins of FMDV. Eleven out of twelve vaccinated cattle that were shown to be persistently infected with FMDV up to or beyond 28 days post challenge, were also detected by the IgA test on saliva. With some modification and further validation, this test could be useful in post-vaccination surveillance to help confirm the absence of sub-clinical infection in order to regain the FMD-free status of a region or country.

The 'think test': a further technique to elicit hyperventilation.

PubMed Central

Nixon, P G; Freeman, L J

1988-01-01

Hyperventilation can undermine cardiovascular homeostasis by generating autonomic imbalance, sympathetic dominance, hypokalaemia, and intracellular alkalosis with calcium ion shifts. The role of hyperventilation in episodic disorders such as arrhythmia and coronary vasospasm can be difficult to identify if the patient does not present in an attack and so a provocation challenge is required. Today, the standard challenge is the forced hyperventilation provocation test (FHPT). A capnograph enables the resting end-tidal PCO2 to be compared with the level 3 min after the period of overbreathing. We report the use of a patient-specific challenge. After the FHPT, the subject is invited to close his eyes and think about the circumstances of an attack, feelings and sensations experienced (breathing is not mentioned) or topics that were seen to disturb the rhythm of breathing when the medical history was taken. A fall of end-tidal PCO2 of 10 mmHg or more lasting at least one minute was taken as a positive response. Out of 57 patients with cardiovascular symptoms suggesting a hypocapnic influence, resting hypocapnia (end-tidal PCO2 = 30 mmHg) was present in 3 (5%). Of the remaining 54, the FHPT was positive in 16 (30%) and the 'think test' in 33 (61%). This suggests that patient-specific stimulation has advantages over an unspecific challenge in testing for episodic hypocapnia. PMID:3133476

Methodological strategies in using home sleep apnea testing in research and practice.

PubMed

Miller, Jennifer N; Schulz, Paula; Pozehl, Bunny; Fiedler, Douglas; Fial, Alissa; Berger, Ann M

2017-11-14

Home sleep apnea testing (HSAT) has increased due to improvements in technology, accessibility, and changes in third party reimbursement requirements. Research studies using HSAT have not consistently reported procedures and methodological challenges. This paper had two objectives: (1) summarize the literature on use of HSAT in research of adults and (2) identify methodological strategies to use in research and practice to standardize HSAT procedures and information. Search strategy included studies of participants undergoing sleep testing for OSA using HSAT. MEDLINE via PubMed, CINAHL, and Embase with the following search terms: "polysomnography," "home," "level III," "obstructive sleep apnea," and "out of center testing." Research articles that met inclusion criteria (n = 34) inconsistently reported methods and methodological challenges in terms of: (a) participant sampling; (b) instrumentation issues; (c) clinical variables; (d) data processing; and (e) patient acceptability. Ten methodological strategies were identified for adoption when using HSAT in research and practice. Future studies need to address the methodological challenges summarized in this paper as well as identify and report consistent HSAT procedures and information.

Allergenicity and safety of recombinant human C1 esterase inhibitor in patients with allergy to rabbit or cow's milk.

PubMed

van den Elzen, Mignon T; van Os-Medendorp, Harmieke; Röckmann-Helmbach, Heike; van Hoffen, Els; Lebens, Ans F M; van Doorn, Helma; Klemans, Rob J B; Bruijnzeel-Koomen, Carla A F M; Hack, C Erik; Kaufman, Leonard; Relan, Anurag; Knulst, André C

2016-08-01

Recombinant human C1 inhibitor (rhC1INH) for on-demand treatment of hereditary angioedema is purified from milk of transgenic rabbits. It contains low amounts (<0.002%) of host-related impurities, which could trigger hypersensitivity reactions in patients with rabbit allergy (RA) and/or cow's milk allergy (CMA). This study is an assessment of allergenicity and safety of rhC1INH in patients with RA and/or CMA. Patients with CMA and/or RA underwent skin prick test (SPT), intracutaneous test (ICT), and, when results for both were negative, subcutaneous (SC) challenge with up to 2100U (14 mL) rhC1INH. The negative predictive value of the skin test protocol was calculated, defined as the ratio of patients without systemic symptoms of hypersensitivity following SC challenge, over the number of patients having tested negative for both the SPT and the ICT. Adverse events after exposure to rhC1INH were recorded. Twenty-six patients with RA and/or CMA were enrolled. Twenty-four had negative SPT and ICT results for rhC1INH, whereas 2 had negative SPT result but positive ICT result to rhC1INH (only the highest concentration). Twenty-two patients with negative SPT and ICT results underwent SC challenge. None developed allergic symptoms. Local treatment-emergent adverse events occurred in 7 patients (32%) after SC challenge. In 5 these were considered drug related. All were mild. None of the patients with negative SPT and ICT results for rhC1INH had allergic symptoms during rhC1INH challenge. The negative predictive value of the combination of SPT and ICT for the outcome of the SC challenge was 100% (95% CI, 84.6%-100%). SC administration of rhC1INH was well tolerated. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Development and validation of a real-time TaqMan assay for the detection and enumeration of Pseudomonas fluorescens ATCC 13525 used as a challenge organism in testing of food equipments.

PubMed

Saha, Ratul; Bestervelt, Lorelle L; Donofrio, Robert S

2012-02-01

Pseudomonas fluorescens ATCC 13525 is used as the challenge organism to evaluate the efficacy of the clean-in-place (CIP) process of food equipment (automatic ice-maker) as per NSF/ANSI Standard 12. Traditional culturing methodology is presently used to determine the concentration of the challenge organism, which takes 48 h to confirm the cell density. Storage of the challenge preparation in the refrigerator might alter the cell density as P. fluorescens is capable of growing at 4 °C. Also, background organism can grow on the Pseudomonas F agar (PFA) used for the recovery of P. fluorescens thus affecting the results of the test. Real-time TaqMan assay targeting the cpn60 gene was developed for the enumeration and the identification of P. fluorescens because of its specificity, accuracy, and shorter turnaround time. The TaqMan primer-probe pair developed using the Allele ID® 7.0 probe design software was highly specific and sensitive for the target organism. The sensitivity of the assay was 10 colony forming units (CFU)/mL. The assay was also successful in determining the concentration of the challenge preparation within 2 h. Based on these observations, TaqMan assay targeting the cpn60 gene can be efficiently used for strain level identification and enumeration of bacteria. Pseudomonas fluorescens ATCC 13525 is used as a challenge organism in the efficacy testing of clean-in-place process of food equipments. Currently, culturing technique is used for its identification and estimation, which is not only time-consuming but also prone to error. Real-time TaqMan assay is more specific, sensitive, and accurate along with a shorter turnaround time compared to culturing techniques, thereby increasing the overall quality of the testing methodology to evaluate the clean-in-place process critical for the food industry to protect public health and safety. © 2012 Institute of Food Technologists®

Workshop proceedings: challenges and opportunities in evaluating protein allergenicity across biotechnology industries.

PubMed

Stagg, Nicola J; Ghantous, Hanan N; Ladics, Gregory S; House, Robert V; Gendel, Steven M; Hastings, Kenneth L

2013-01-01

A workshop entitled "Challenges and Opportunities in Evaluating Protein Allergenicity across Biotechnology Industries" was held at the 51st Annual Meeting of the Society of Toxicology (SOT) in San Francisco, California. The workshop was sponsored by the Biotechnology Specialty Section of SOT and was designed to present the science-based approaches used in biotechnology industries to evaluate and regulate protein allergenicity. A panel of experts from industry and government highlighted the allergenicity testing requirements and research in the agricultural, pharmaceutical/biopharma, and vaccine biotechnology industries and addressed challenges and opportunities for advancing the science of protein allergenicity. The main learning from the workshop was that immunoglobulin E-mediated allergenicity of biotechnology-derived products is difficult to assess without human data. The approaches currently being used to evaluate potential for allergenicity across biotechnology industries are very different and range from bioinformatics, in vitro serology, in vivo animal testing, in vitro and in vivo functional assays, and "biosimilar" assessments (ie, biotherapeutic equivalents to innovator products). The challenge remains with regard to the different or lack of regulatory requirements for allergenicity testing across industries, but the novel approaches being used with bioinformatics and biosimilars may lead to opportunities in the future to collaborate across biotechnology industries.

Individual and Collective Protection Program

DTIC Science & Technology

2007-11-30

98 8.2.1 PREPARATION OF STOCK SUSPENSION OF MS2 COLIPHAGE ...103 8.3.1 PROCEDURE FOR ASSAYING MS2 COLIPHAGE ...CHALLENGE NUMBER OF TEST MICROORGANISMS..................106 8.4.1 METHOD FOR DETERMINATION OF CHALLENGE NUMBER OF MS2 COLIPHAGE

42 CFR 493.959 - Immunohematology.

Code of Federal Regulations, 2014 CFR

2014-10-01

... challenges per testing event a program must provide for each analyte or test procedure is five. Analyte or... Compatibility testing Antibody identification (d) Evaluation of a laboratory's analyte or test performance. HHS... program must compare the laboratory's response for each analyte with the response that reflects agreement...

42 CFR 493.959 - Immunohematology.

Code of Federal Regulations, 2013 CFR

2013-10-01

... challenges per testing event a program must provide for each analyte or test procedure is five. Analyte or... Compatibility testing Antibody identification (d) Evaluation of a laboratory's analyte or test performance. HHS... program must compare the laboratory's response for each analyte with the response that reflects agreement...

42 CFR 493.959 - Immunohematology.

Code of Federal Regulations, 2012 CFR

2012-10-01

... challenges per testing event a program must provide for each analyte or test procedure is five. Analyte or... Compatibility testing Antibody identification (d) Evaluation of a laboratory's analyte or test performance. HHS... program must compare the laboratory's response for each analyte with the response that reflects agreement...

42 CFR 493.959 - Immunohematology.

Code of Federal Regulations, 2011 CFR

2011-10-01

... challenges per testing event a program must provide for each analyte or test procedure is five. Analyte or... Compatibility testing Antibody identification (d) Evaluation of a laboratory's analyte or test performance. HHS... program must compare the laboratory's response for each analyte with the response that reflects agreement...

Overview of Propellant Delivery Systems at the NASA John C. Stennis Space Center

NASA Technical Reports Server (NTRS)

Haselmaier, L. Haynes; Field, Robert E.; Ryan, Harry M.; Dickey, Jonathan C.

2006-01-01

A wide range of rocket propulsion test work occurs at he NASA John C. Stennis Space Center (SSC) including full-scale engine test activities at test facilities A-1, A-2, B-1 and B-2 as well as combustion device research and development activities at the E-Complex (E-1, E-2. E-3 and E-4) test facilities. One of the greatest challenges associated with operating a test facility is maintaining the health of the primary propellant system and test-critical support systems. The challenge emerges due to the fact that the operating conditions of the various system components are extreme (e.g., low temperatures, high pressures) and due to the fact that many of the components and systems are unique. The purpose of this paper is to briefly describe the experience and modeling techniques that are used to operate the unique test facilities at NASA SSC that continue to support successful propulsion testing.

Truth in Testing Legislation and Private Property Concepts.

ERIC Educational Resources Information Center

Burns, Daniel J.

1981-01-01

Truth in testing laws are subject to challenge on the grounds that they invade federally protected rights and interests of the test-makers through the due process clauses of the Constitution and federal copyright protections. (Author/MLF)

Test Driven Development of Scientific Models

NASA Technical Reports Server (NTRS)

Clune, Thomas L.

2014-01-01

Test-Driven Development (TDD), a software development process that promises many advantages for developer productivity and software reliability, has become widely accepted among professional software engineers. As the name suggests, TDD practitioners alternate between writing short automated tests and producing code that passes those tests. Although this overly simplified description will undoubtedly sound prohibitively burdensome to many uninitiated developers, the advent of powerful unit-testing frameworks greatly reduces the effort required to produce and routinely execute suites of tests. By testimony, many developers find TDD to be addicting after only a few days of exposure, and find it unthinkable to return to previous practices.After a brief overview of the TDD process and my experience in applying the methodology for development activities at Goddard, I will delve more deeply into some of the challenges that are posed by numerical and scientific software as well as tools and implementation approaches that should address those challenges.

Side effects induced by the acute levodopa challenge in Parkinson's Disease and atypical parkinsonisms.

PubMed

Vasta, Rosario; Nicoletti, Alessandra; Mostile, Giovanni; Dibilio, Valeria; Sciacca, Giorgia; Contrafatto, Donatella; Cicero, Calogero Edoardo; Raciti, Loredana; Luca, Antonina; Zappia, Mario

2017-01-01

Acute levodopa challenge may be performed to predict levodopa chronic responsiveness. The aim of the study was to investigate frequency of side effects during the acute levodopa challenge in PD and atypical parkinsonisms. We enrolled 34 de novo PD patients and 29 patients affected by atypical parkinsonisms (Multiple System Atrophy, MSA, n = 10; Progressive Supranuclear Palsy, PSP, n = 12 and Corticobasal Degeneration, CBD, n = 7) who underwent an acute levodopa challenge. Side effects occurring during test were recorded. Side effects were more frequent among atypical parkinsonisms as unique group when compared to PD patients (64.3% versus 23.5%; p-value 0.002) with an adjusted OR of 4.36 (95%CI 1.40-13.5). Each atypical parkinsonisms showed almost double occurrence of side effects (MSA 90%, PSP 41.7% and CBD 57%). Side effects during acute levodopa challenge may be frequent in atypical parkinsonisms. This information could be useful in order to better prepare the patient for the test. Furthermore, it could represent a useful cue in differential diagnosis with PD.

Challenges of using Hospital Information Systems by nurses: comparing academic and non-academic hospitals.

PubMed

Ahmadian, Leila; Dorosti, Nafise; Khajouei, Reza; Gohari, Sadrieh Hajesmaeel

2017-06-01

Hospital Information Systems (HIS) are used for easy access to information, improvement of documentation and reducing errors. Nonetheless, using these systems is faced with some barriers and obstacles. This study identifies the challenges and the obstacles of using these systems in the academic and non-academic hospitals in Kerman. This is a cross-sectional study which was carried out in 2015. The statistical population in this study consisted of the nurses who had been working in the academic and non-academic hospitals in Kerman. A questionnaire consisting of two sections was used. The first section consisted of the demographic information of the participants and the second section comprised 34 questions about the challenges of HIS use. Data were analyzed by the descriptive and statistical analysis (t-test, and ANOVA) using SPSS 19 software. The most common and important challenges in the academic hospitals were about human environment factors, particularly "negative attitude of society toward using HIS". In the non-academic hospitals, the most common and important challenges were related to human factors, and among them, "no incentive to use system" was the main factor. The results of the t-test method revealed that there was a significant relationship between gender and the mean score of challenges related to the organizational environment category in the academic hospitals and between familiarity with HIS and mean score of human environment factors (p<0.05). The results of the ANOVA test also revealed that the educational degree and work experience in the healthcare environment (years) in the academic hospitals have a significant relationship with the mean score related to the hardware challenges, as well, experience with HIS has a significant relationship, with the mean score related to the human challenges (p<0.05). The most important challenges in using the information systems are the factors related to the human environment and the human factors. The results of this study can bring a good perspective to the policy makers and the managers regarding obstacles of using HISs from the nurses' perspective, so that they can solve their problems and can successfully implement these systems.

Challenges in the delivery of public HIV testing and counselling (HTC) in Douala, Cameroon: providers perspectives and implications on quality of HTC services.

PubMed

Ngangue, Patrice; Gagnon, Marie-Pierre; Bedard, Emmanuelle

2017-04-08

The Cameroon government has made HIV testing and counselling (HTC) a priority in its HIV/AIDS strategic plan. However, there is a dearth of literature on the perspectives of providers on the quality of HTC services. The aim of this study was to explore challenges in the provision of HTC services and their implications on quality of HTC services in Douala's district hospitals. Two primary data collection methods supported by the Donabedian's model of healthcare were used to explain the challenges in the provision of HTC services and their implications on quality of HTC services. This consisted of semi-structured individual interviews with 6 nurses and 16 lay counsellors and a non-participant observation of the physical environment for HTC by site. The study sites were the prevention and voluntary testing and counselling centre (PVTCC) of the six district hospitals of the city of Douala. The study reveals concerns about confidentiality and privacy during the counselling sessions due to inadequate and limited space. An absence of consent, even verbal, was reported in one PVTCC. There is no specific accredited training curriculum that leads to a formal registration as a PVTCC staff, and some lay counsellors work without training. Lay counsellors carry the burden of HIV counselling, but the majority of them work for many years without remuneration and recognition. Another quality challenge is the high workload in the district hospitals' lab, which leads to long waiting times for HIV test results, thus contributing to failure to return for results. The findings of this study highlighted some issues such as lack of adequate space and equipment for HIV testing and counselling that hinder the quality of HTC services and should challenge the health authorities of Cameroon on the need to reorganize HTC services and create a national HIV quality assurance program.

Measurement of allergen-specific IgG in serum is of limited value for the management of dogs diagnosed with cutaneous adverse food reactions.

PubMed

Hagen-Plantinga, E A; Leistra, M H G; Sinke, J D; Vroom, M W; Savelkoul, H F J; Hendriks, W H

2017-02-01

Conflicting results have been reported in the literature in terms of the usefulness of serological testing for IgG against food allergens in dogs with cutaneous adverse food reaction (CAFR). The aim of the present study was to evaluate the suitability of a commercially available IgG ELISA for identifying food allergens in dogs, by challenging dogs with specific food ingredients, selected on the basis of IgG reactivity in serum samples. A total of 24 adult dogs with CAFR were enrolled into the study and 16 healthy dogs were included as a control group. Blood samples were obtained for measurement of specific IgG antibodies against 39 commonly used pet food ingredients by ELISA. Participating owners were surveyed to obtain information on their pet's dietary history. Eleven healthy control dogs and 12 dogs with CAFR were subsequently challenged in a blinded cross-over design experiment with both positive and negative food ingredients, selected on the basis of the ELISA test results. There was substantial individual variation in ELISA test results to the various food allergens, but no significant difference in IgG reactivity comparing the CAFR and control groups. None of the control dogs developed any clinical signs of an allergic reaction during the dietary challenge study. In the CAFR group, six of 12 dogs developed clinical signs after the negative challenge, and two of nine dogs developed clinical signs after the positive challenge. It was concluded that the ELISA test for dietary allergen-specific IgG is of limited value in the management of dogs with CAFR. Copyright © 2017 Elsevier Ltd. All rights reserved.

Syphilis testing practices in the Americas.

PubMed

Trinh, Thuy T; Kamb, Mary L; Luu, Minh; Ham, D Cal; Perez, Freddy

2017-09-01

To present the findings of the Pan American Health Organization's 2014 survey on syphilis testing policies and practices in the Americas. Representatives of national/regional reference and large, lower-level laboratories from 35 member states were invited to participate. A semi-structured, electronically administered questionnaire collected data on syphilis tests, algorithms, equipment/commodities, challenges faced and basic quality assurance (QA) strategies employed (i.e. daily controls, standard operating procedures, technician training, participating in external QA programmes, on-site evaluations). The 69 participating laboratories from 30 (86%) member states included 41 (59%) national/regional reference and 28 (41%) lower-level laboratories. Common syphilis tests conducted were the rapid plasma reagin (RPR) (62% of surveyed laboratories), venereal disease research laboratory (VDRL) (54%), fluorescent treponemal antibody absorption (FTA-ABS) (41%) and Treponema pallidum haemagglutination assay (TPHA) (32%). Only three facilities reported using direct detection methods, and 28 (41% overall, 32% of lower-level facilities) used rapid tests. Most laboratories (62%) used only traditional testing algorithms (non-treponemal screening and treponemal confirmatory testing); however, 12% used only a reverse sequence algorithm (treponemal test first), and 14% employed both algorithms. Another nine (12%) laboratories conducted only one type of serologic test. Although most reference (97%) and lower-level (89%) laboratories used at least one QA strategy, only 16% reported using all five basic strategies. Commonly reported challenges were stock-outs of essential reagents or commodities (46%), limited staff training (73%) and insufficient equipment (39%). Many reference and clinical laboratories in the Americas face challenges in conducting appropriate syphilis testing and in ensuring quality of testing. © 2017 John Wiley & Sons Ltd The Pan-American Health Organization retains copyright and all other rights in the manuscript of this article as submitted for publication.

Role of specific IgE and skin-prick testing in predicting food challenge results to baked egg.

PubMed

Cortot, Catherine F; Sheehan, William J; Permaul, Perdita; Friedlander, James L; Baxi, Sachin N; Gaffin, Jonathan M; Dioun, Anahita F; Hoffman, Elaine B; Schneider, Lynda C; Phipatanakul, Wanda

2012-01-01

Previous studies suggest that children with egg allergy may be able to tolerate baked egg. Reliable predictors of a successful baked egg challenge are not well established. We examined egg white-specific IgE levels, skin-prick test (SPT) results, and age as predictors of baked egg oral food challenge (OFC) outcomes. We conducted a retrospective chart review of children, aged 2-18 years, receiving an egg white-specific IgE level, SPT, and OFC to baked egg from 2008 to 2010. Fifty-two oral baked egg challenges were conducted. Of the 52 challenges, 83% (n = 43) passed and 17% (n = 9) failed, including 2 having anaphylaxis. Median SPT wheal size was 12 mm (range, 0-35 mm) for passed challenges and 17 mm (range, 10-30 mm) for failed challenges (p = 0.091). The negative predictive value for passing the OFC was 100% (9 of 9) if SPT wheal size was <10 mm. Median egg white-specific IgE was 2.02 kU/L (range, <0.35-13.00 kU/L) for passed challenges and 1.52 kU/L (range, 0.51-6.10 kU/L) for failed challenges (p = 0.660). Receiver operating characteristic (ROC) curve analysis for SPT revealed an area under the curve (AUC) of 0.64. ROC curve analysis for egg white-specific IgE revealed an AUC of 0.63. There was no significant difference in age between patients who failed and those who passed (median = 8.8 years versus 7.0 years; p = 0.721). Based on our sample, SPT, egg white-specific IgE and age are not good predictors of passing a baked egg challenge. However, there was a trend for more predictability with SPT wheal size.

Skin prick testing and peanut-specific IgE can predict peanut challenge outcomes in preschoolchildren with peanut sensitization.

PubMed

Johannsen, H; Nolan, R; Pascoe, E M; Cuthbert, P; Noble, V; Corderoy, T; Franzmann, A; Loh, R; Prescott, S L

2011-07-01

The rise in peanut allergy is a source of considerable burden in the community. A growing number of preschoolchildren have been identified as peanut sensitized in the course of investigation of other allergic conditions. Although many have never knowingly ingested peanuts and their clinical reactivity is not known, it has been common practice to place these children on avoidance diets for many years. To determine the utility of skin prick tests (SPT) and fluorescent-enzyme immunoassays (FEIA) for identifying either peanut allergy or tolerance in preschoolchildren with peanut sensitization. Forty-nine preschoolchildren (<5 years of age) with peanut sensitization (SPT ≥ 2 mm or peanut-specific IgE ≥ 0.35 kU/L) but unknown clinical reactivity had graded open peanut challenges reaching a total of 11 g. A positive challenge was defined as an objective IgE-mediated reaction during challenge or the 2-h observation. Forty-nine percent (24/49) of children had positive challenges. An SPT of >7 mm on the day of challenge predicted a positive challenge with a sensitivity of 83% and a negative predictive value (NPV) of 84%. An FEIA of >2.0 kU/L showed a sensitivity of 79% and an NPV of 80%. Predicting challenge outcome from a combination of SPT and FEIA (SPT >7 and/or FEIA >2 is positive) increased sensitivity to 96% and NPV to 95%. At least half of preschoolchildren with peanut sensitization and no antecedent history of peanut ingestion can tolerate peanuts. A SPT<7 mm and FEIA<2 kU/L identify children most likely to tolerate peanut, with only a 5% likelihood of failing an oral challenge. This study assists clinicians considering challenges in very young peanut-sensitized children. © 2011 Blackwell Publishing Ltd.

Enhancement of a small bowel obstruction model using the gastrografin® challenge test.

PubMed

Goussous, Naeem; Eiken, Patrick W; Bannon, Michael P; Zielinski, Martin D

2013-01-01

Based on a previous published data on small bowel obstruction (SBO), a management model for predicting the need for exploration has been adopted in our institution. In our model, patients presenting with three criteria-the history of obstipation, the presence of mesenteric edema, and the lack of small bowel fecalization on computed tomography (CT)-undergo exploration. Patients with two or less features were managed nonoperatively. An alternative tool for predicting need for operative intervention is Gastrografin (GG) challenge test. We hypothesized that the GG challenge test, when used in combination with our prior model, will decrease the rate of explorations in patients not meeting the criteria for immediate operation. An approval from IRB was obtained to review patients admitted with a diagnosis of SBO from November 2010 to September 2011. All patients presenting with signs of ischemia, patients with all three model criteria defined previously, and those who had an abdominal operation within 6 weeks of diagnosis were excluded. All patients had an abdominal/pelvic CT and GG challenge at the time of diagnosis. Patients were compared to historic controls managed without the GG challenge (from July to December 2009). Successful GG challenge was defined as the presence of contrast in the colon after a follow-up film or a bowel movement. Data were presented as medians or percentages; significance was considered at p < 0.05. One hundred and twenty-five patients with a diagnosis of small bowel obstruction were identified wherein 47 % were males. Fifty-three received a GG challenge (study), and 72 did not have a GG challenge (historic). There was no difference in age (70 vs 65 years), history of prior SBO (51 vs 49 %), history of diabetes mellitus (21 vs 18 %), history of malignancy (32 vs 39 %), or cardiac disease (30 vs 39 %). Both groups had similar number of previous abdominal operations (two vs two). The presence of mesenteric edema (68 vs 75 %), the lack of small bowel fecalization (47 vs 46 %), and a history of obstipation (25 vs 24 %) were similar in both groups. Patients in the study group had a lesser rate of abdominal exploration (25 vs 42 %, p = 0.05) and fewer complications (13 vs 31 %, p = 0.02) compared to the historic control group. There was equivalent incidence of ischemic bowel (4 vs 7 %), duration of hospital stay (4 vs 7 days), duration from admission to operation (2 vs 3 days), and mortality (8 vs 6 %); 44 patients had a successful GG challenge with nine failures. There was a greater rate of exploration in patients with a failed challenge compared to those with a successful challenge (89 vs 11 %, p < 0.01). The use of the GG challenge enhanced the SBO prediction model by decreasing the need for exploration in patients not meeting the criteria for immediate operation. Patients who failed the GG challenge test were much more likely to undergo an exploration.

Radiation Challenges for Electronics in the Vision for Space Exploration

NASA Technical Reports Server (NTRS)

LaBel, Kenneth A.

2006-01-01

The slides present a brief snapshot discussing electronics and exploration-related challenges. Radiation effects have been the prime target, however, electronic parts reliability issues must also be considered. Modern electronics are designed with a 3-5 year lifetime. Upscreening does not improve reliability, merely determines inherent levels. Testing costs are driven by device complexity; they increase tester complexity, beam requirements, and facility choices. Commercial devices may improve performance, but are not cost panaceas. There is need for a more cost-effective access to high energy heavy ion facilities such as NSCL and NSRL. Costs for capable test equipment can run more than $1M for full testing.

Neonatal endocrine emergencies: a primer for the emergency physician.

PubMed

Park, Elizabeth; Pearson, Nadia M; Pillow, M Tyson; Toledo, Alexander

2014-05-01

The resuscitation principles of securing the airway and stabilizing hemodynamics remain the same in any neonatal emergency. However, stabilizing endocrine disorders may prove especially challenging. Several organ systems are affected simultaneously and the clinical presentation can be subtle. Although not all-inclusive, the implementation of newborn screening tests has significantly reduced morbidity and mortality in neonates. Implementing routine screening tests worldwide and improving the accuracy of present tests remains the challenge for healthcare providers. With further study of these disorders and best treatment practices we can provide neonates presenting to the emergency department with the best possible outcomes. Copyright © 2014 Elsevier Inc. All rights reserved.

Exploring Equity Properties in Equating Using AP® Examinations. Research Report No. 2012-4

ERIC Educational Resources Information Center

Lee, Eunjung; Lee, Won-Chan; Brennan, Robert L.

2012-01-01

In almost all high-stakes testing programs, test equating is necessary to ensure that test scores across multiple test administrations are equivalent and can be used interchangeably. Test equating becomes even more challenging in mixed-format tests, such as Advanced Placement Program® (AP®) Exams, that contain both multiple-choice and constructed…

Regulatory toxicology in the twenty-first century: challenges, perspectives and possible solutions.

PubMed

Tralau, Tewes; Oelgeschläger, Michael; Gürtler, Rainer; Heinemeyer, Gerhard; Herzler, Matthias; Höfer, Thomas; Itter, Heike; Kuhl, Thomas; Lange, Nikola; Lorenz, Nicole; Müller-Graf, Christine; Pabel, Ulrike; Pirow, Ralph; Ritz, Vera; Schafft, Helmut; Schneider, Heiko; Schulz, Thomas; Schumacher, David; Zellmer, Sebastian; Fleur-Böl, Gaby; Greiner, Matthias; Lahrssen-Wiederholt, Monika; Lampen, Alfonso; Luch, Andreas; Schönfelder, Gilbert; Solecki, Roland; Wittkowski, Reiner; Hensel, Andreas

2015-06-01

The advent of new testing systems and "omics"-technologies has left regulatory toxicology facing one of the biggest challenges for decades. That is the question whether and how these methods can be used for regulatory purposes. The new methods undoubtedly enable regulators to address important open questions of toxicology such as species-specific toxicity, mixture toxicity, low-dose effects, endocrine effects or nanotoxicology, while promising faster and more efficient toxicity testing with the use of less animals. Consequently, the respective assays, methods and testing strategies are subject of several research programs worldwide. On the other hand, the practical application of such tests for regulatory purposes is a matter of ongoing debate. This document summarizes key aspects of this debate in the light of the European "regulatory status quo", while elucidating new perspectives for regulatory toxicity testing.

The Internationalization of Testing and New Models of Test Delivery on the Internet

ERIC Educational Resources Information Center

Bartram, Dave

2006-01-01

The Internet has opened up a whole new set of opportunities for advancing the science of psychometrics and the technology of testing. It has also created some new challenges for those of us involved in test design and testing. In particular, we are seeing impacts from internationalization of testing and new models for test delivery. These are…

Design Challenges Encountered in a Propulsion-Controlled Aircraft Flight Test Program

NASA Technical Reports Server (NTRS)

Maine, Trindel; Burken, John; Burcham, Frank; Schaefer, Peter

1994-01-01

The NASA Dryden Flight Research Center conducted flight tests of a propulsion-controlled aircraft system on an F-15 airplane. This system was designed to explore the feasibility of providing safe emergency landing capability using only the engines to provide flight control in the event of a catastrophic loss of conventional flight controls. Control laws were designed to control the flightpath and bank angle using only commands to the throttles. Although the program was highly successful, this paper highlights some of the challenges associated with using engine thrust as a control effector. These challenges include slow engine response time, poorly modeled nonlinear engine dynamics, unmodeled inlet-airframe interactions, and difficulties with ground effect and gust rejection. Flight and simulation data illustrate these difficulties.

Challenges in Rotorcraft Acoustic Flight Prediction and Validation

NASA Technical Reports Server (NTRS)

Boyd, D. Douglas, Jr.

2003-01-01

Challenges associated with rotorcraft acoustic flight prediction and validation are examined. First, an outline of a state-of-the-art rotorcraft aeroacoustic prediction methodology is presented. Components including rotorcraft aeromechanics, high resolution reconstruction, and rotorcraft acoustic prediction arc discussed. Next, to illustrate challenges and issues involved, a case study is presented in which an analysis of flight data from a specific XV-15 tiltrotor acoustic flight test is discussed in detail. Issues related to validation of methodologies using flight test data are discussed. Primary flight parameters such as velocity, altitude, and attitude are discussed and compared for repeated flight conditions. Other measured steady state flight conditions are examined for consistency and steadiness. A representative example prediction is presented and suggestions are made for future research.

Structural Analysis of a Tablet PC Based Language Test

ERIC Educational Resources Information Center

Magal Royo, Teresa; Garcia Laborda, Jesus; Gimenez Lopez, Jose Luis; Otero de Juan, Nuria

2015-01-01

Ubiquitous language learning and testing has become a new challenging trend. Budget constraints in Europe and the rest of the world have made this way of delivery very attractive for materials designers as well as language testing organizations. Ubiquitous testing has a very especial interest in low and medium stakes language testing in which…

The Current Often Implemented Fitness Tests in Physical Education Programs: Problems and Future Directions

ERIC Educational Resources Information Center

Keating, Xiaofen Deng

2003-01-01

This paper aims to examine current nationwide youth fitness test programs, address problems embedded in the programs, and possible solutions. The current Fitnessgram, President's Challenge, and YMCA youth fitness test programs were selected to represent nationwide youth fitness test programs. Sponsors of the nationwide youth fitness test programs…

Can interpreting sediment toxicity tests a mega sites benefit from novel approaches to normalization to address batching of tests?

EPA Science Inventory

Sediment toxicity tests are a key tool used in Ecological Risk Assessments for contaminated sediment sites. Interpreting test results and defining toxicity is often a challenge. This is particularly true at mega sites where the testing regime is large, and by necessity performed ...

Aerothermodynamics of Blunt Body Entry Vehicles. Chapter 3

NASA Technical Reports Server (NTRS)

Hollis, Brian R.; Borrelli, Salvatore

2011-01-01

In this chapter, the aerothermodynamic phenomena of blunt body entry vehicles are discussed. Four topics will be considered that present challenges to current computational modeling techniques for blunt body environments: turbulent flow, non-equilibrium flow, rarefied flow, and radiation transport. Examples of comparisons between computational tools to ground and flight-test data will be presented in order to illustrate the challenges existing in the numerical modeling of each of these phenomena and to provide test cases for evaluation of Computational Fluid Dynamics (CFD) code predictions.

Aerothermodynamics of blunt body entry vehicles

NASA Astrophysics Data System (ADS)

Hollis, Brian R.; Borrelli, Salvatore

2012-01-01

In this chapter, the aerothermodynamic phenomena of blunt body entry vehicles are discussed. Four topics will be considered that present challenges to current computational modeling techniques for blunt body environments: turbulent flow, non-equilibrium flow, rarefied flow, and radiation transport. Examples of comparisons between computational tools to ground and flight-test data will be presented in order to illustrate the challenges existing in the numerical modeling of each of these phenomena and to provide test cases for evaluation of computational fluid dynamics (CFD) code predictions.

Preclinical molecular imaging: development of instrumentation for translational research with small laboratory animals.

PubMed

Mejia, Jorge; Miranda, Ana Claudia Camargo; Durante, Ana Claudia Ranucci; Oliveira, Larissa Rolim de; Barboza, Marycel Rosa Felisa Figols de; Rosell, Katerin Taboada; Jardim, Daniele Pereira; Campos, Alexandre Holthausen; Reis, Marilia Alves Dos; Catanoso, Marcela Forli; Galvis-Alonso, Orfa Yineth; Cabral, Francisco Romero

2016-01-01

To present the result of upgrading a clinical gamma-camera to be used to obtain in vivo tomographic images of small animal organs, and its application to register cardiac, renal and neurological images. An updated version of the miniSPECT upgrading device was built, which is composed of mechanical, electronic and software subsystems. The device was attached to a Discovery VH (General Electric Healthcare) gamma-camera, which was retired from the clinical service and installed at the Centro de Imagem Pré-Clínica of the Hospital Israelita Albert Einstein. The combined system was characterized, determining operational parameters, such as spatial resolution, magnification, maximum acceptable target size, number of projections, and acquisition and reconstruction times. Images were obtained with 0.5mm spatial resolution, with acquisition and reconstruction times between 30 and 45 minutes, using iterative reconstruction with 10 to 20 iterations and 4 projection subsets. The system was validated acquiring in vivo tomographic images of the heart, kidneys and brain of normal animals (mice and adult rats), using the radiopharmaceuticals technetium-labeled hexakis-2-methoxy-isobutyl isonitrile (99mTc-Sestamibi), technetium-labeled dimercaptosuccinic acid (99mTc-DMSA) and technetium-labeled hexamethyl propyleneamine oxime (99mTc-HMPAO). This kind of application, which consists in the adaptation for an alternative objective of already existing instrumentation, resulted in a low-cost infrastructure option, allowing to carry out large scale in vivo studies with enhanced quality in several areas, such as neurology, nephrology, cardiology, among others. Apresentar o resultado da adaptação de uma gama câmara clínica para uso dedicado na obtenção de imagens tomográficas in vivo de órgãos de pequenos animais de experimentação, e de sua aplicação na obtenção de imagens cardíacas, renais e neurológicas. Foi construída uma versão atualizada do dispositivo de adaptação miniSPECT, composto por três subsistemas: mecânico, eletrônico e de software. O dispositivo foi montado em uma câmara Discovery VH da General Electric Healthcare, retirada do serviço clínico e instalada no Centro de Imagem Pré-Clínica do Hospital Israelita Albert Einstein. O sistema combinado foi caracterizado, determinando parâmetros de funcionamento como resolução espacial, magnificação, limites de tamanho dos alvos de estudo, número de projeções, tempo de registro e tempo de reconstrução das imagens tomográficas. Foram obtidas imagens com resolução espacial de até 0,5mm, com tempos de registro e reconstrução de 30 a 45 minutos, utilizando reconstrução iterativa com 10 a 20 iterações e 4 subconjuntos de projeções. O sistema foi validado obtendo imagens tomográficas in vivo do coração, dos rins e do cérebro de animais normais (camundongos e ratos adultos), utilizando os radiofármacos hexaquis-2-metoxi-isobutil-isonitrila marcado com 99mTc (Sestamibi-99mTc), ácido dimercaptosuccínico marcado com 99mTc (DMSA-99mTc) e hexametil-propileno-amina-oxima marcada com 99mTc (HMPAO-99mTc). Este tipo de aplicação, que consiste na adaptação para um objetivo alternativo de instrumentação já existente, constituiu-se em uma opção de infraestrutura de baixo custo, que permite realizar estudos in vivo em larga escala, com qualidade aprimorada, em áreas diversas, como neurologia, nefrologia, cardiologia, entre outras.

Recent diagnostic and therapeutic approaches to prenatally and perinatally diagnosed hydronephrosis and their implementation in the University Clinical Hospital Mostar.

PubMed

Mandić, Vjekoslav; Martinović, Vlatka; Kvesić, Ante; Bukvić, Nado; Skitarelić, Nataša; Brekalo, Zdrinko; Ivanković, Krunoslav; Šetka, Violeta

2015-03-01

A shift of the diagnostics of urological malformations towards the fetal age by means of ultrasound, especially hydronephrosis which, apart from reflux, is the most frequent developmental urological disorder, opened many dilemmas and debates. In the course of more than three decades the application of this diagnostic approach to the problem of hydrone- phrosis became a routine clinical practice in all modern clinics. In this paper we present the problems related to this diagnostic method and its delayed application in the Mostar University Clinical Hospital. Along with the exposition of a general approach to the problem of hydronephrosis we briefly present our modest collection of cases which points to the most recent trend of a vigorous medical development in this region, despite unfavorable overall conditions which prevailed so far. The observation included 56 children with prenatal, perinatal and early age determination of pyelon dilatation by means of ultrasonic exploration who were treated surgically. Of this number 32 (57.14%) were male, and 24 (42.86%) female children. Of the observed patients 56 had unilateral and 6 had bilateral pyelon dilatation so that 62 kidneys in all were observed and treated. The dilatation was determined prenatally in 24 (38.7%) out of 62 kidneys observed in all, in 7 (11.29%) the disorder was observed perinatally and in remaining 31 cases (49.9%) it manifested during early childhood, school age, even at the age of pre-puberty. Of the children with prenatally and perinatally determined dilatation, in 14 (45.16%) out of 31 (100.0%) observed kidneys the ap radius of the dilated pyelon was between 10-15 mm, and in 17 (54.84%) more than 15 mm. Along with other examinations (MAG3 and DMSA) the patients were followed-up by ultrasonic exploration of the observed kidney for 6 to 30 (average 18) months after postnatal diagnosis; the ultrasonic exploration was repeated in intervals of 6 months. Within 12 months of birth surgical intervention on the pyeloureteral junction was done on all 17 kidneys with an ap radius of the pyelon greater than 15 mm, as well as on 4 kidneys in which ap radius was between 10 and 15 mm. In other 10 kidneys with prenatally and perinatally determined ap radius of 10 to 15 mm the follow-up period was 25 to 30 months (average 275). As the examinations (ultrasound, MAG3 and DMSA) even after this period showed no signs of regression of the dilatation, nor an improvement in patency this provided an indication for surgical intervention with the aim of establishing a normal flow across the pyeloureteral junction. Antibiotic prophylaxis was not applied systematically, but in a targeted manner if the uroinfection was confirmed clinically and in the lab. Through the presentation of cases we demonstrate the relationship of earlier and more recent procedures in the treatment of hydronephrosis in the gravitational area of the Mostar University Clinical Hospital. The fact that some children were subjected to surgical treatment due to hydronephrosis at the time of pre-puberty reflects earlier views on this clinical entity. The successfulness of surgical treatment of hydronephrosis in the observed patients is complete and comparable to medically more developed environments, and our diagnostic capabilities are getting close to that level too. We specially wish to stress the recent introduction of ultrasonic examination of pregnant women and foetus in the third trimester with the aim of an early detection of anomalies and malformations of the urotract as an indicator of a marked medical devel- opment. On the global level there are still inconclusive and opposing opinions on this subject, as is seen in recent literature. The controversies relate to the diagnostics as well as to therapy.

Skin prick testing predicts peanut challenge outcome in previously allergic or sensitized children with low serum peanut-specific IgE antibody concentration.

PubMed

Nolan, Richard C; Richmond, Peter; Prescott, Susan L; Mallon, Dominic F; Gong, Grace; Franzmann, Annkathrin M; Naidoo, Rama; Loh, Richard K S

2007-05-01

Peanut allergy is transient in some children but it is not clear whether quantitating peanut-specific IgE by Skin Prick Test (SPT) adds additional information to fluorescent-enzyme immunoassay (FEIA) in discriminating between allergic and tolerant children. To investigate whether SPT with a commercial extract or fresh foods adds additional predictive information for peanut challenge in children with a low FEIA (<10 k UA/L) who were previously sensitized, or allergic to peanuts. Children from a hospital-based allergy service who were previously sensitized or allergic to peanuts were invited to undergo a peanut challenge unless they had a serum peanut-specific IgE>10 k UA/L, a previous severe reaction, or a recent reaction to peanuts (within two years). SPT with a commercial extract, raw and roasted saline soaked peanuts was performed immediately prior to open challenge in hospital with increasing quantity of peanuts until total of 26.7 g of peanut was consumed. A positive challenge consisted of an objective IgE mediated reaction occurring during the observation period. 54 children (median age of 6.3 years) were admitted for a challenge. Nineteen challenges were positive, 27 negative, five were indeterminate and three did not proceed after SPT. Commercial and fresh food extracts provided similar diagnostic information. A wheal diameter of >or=7 mm of the commercial extract predicted an allergic outcome with specificity 97%, positive predictive value 93% and sensitivity 83%. There was a tendency for an increase in SPT wheal since initial diagnosis in children who remained allergic to peanuts while it decreased in those with a negative challenge. The outcome of a peanut challenge in peanut sensitized or previously allergic children with a low FEIA can be predicted by SPT. In this cohort, not challenging children with a SPT wheal of >or=7 mm would have avoided 15 of 18 positive challenges and denied a challenge to one out of 27 tolerant children.

Technical Challenges for a Comprehensive Test Ban: A historical perspective to frame the future (Invited)

NASA Astrophysics Data System (ADS)

Wallace, T. C.

2013-12-01

In the summer of 1958 scientists from the Soviet block and the US allies met in Geneva to discuss what it would take to monitor a forerunner to a Comprehensive Test Ban Treaty at the 'Conference of Experts to Study the Possibility of Detecting Violations of a Possible Agreement on Suspension of Nuclear Tests'. Although armed with a limited resume of observations, the conference recommended a multi-phenomenology approach (air sampling, acoustics, seismic and electromagnetic) deployed it a network of 170 sites scattered across the Northern Hemisphere, and hypothesized a detection threshold of 1kt for atmospheric tests and 5kt for underground explosions. The conference recommendations spurred vigorous debate, with strong disagreement with the stated detection hypothesis. Nevertheless, the technical challenges posed lead to a very focused effort to improve facilities, methodologies and, most importantly, research and development on event detection, location and identification. In the ensuing 50 years the various challenges arose and were eventually 'solved'; these included quantifying yield determination to enter a Limited Threshold Test Ban, monitoring broad areas of emerging nuclear nations, and after the mid-1990s lowering the global detection threshold to sub-kiloton levels for underground tests. Today there is both an international monitoring regime (ie, the International Monitoring System, or IMS) and a group of countries that have their own national technical means (NTM). The challenges for the international regime are evolving; the IMS has established itself as a very credible monitoring system, but the demand of a CTBT to detect and identify a 'nuclear test' of diminished size (zero yield) poses new technical hurdles. These include signal processing and understanding limits of resolution, location accuracy, integration of heterogeneous data, and accurately characterizing anomalous events. It is possible to extrapolate past technical advances to predict what should be available by 2020; detection of coupled explosions to 100s of tons for all continental areas, as well as a probabilistic assessment of event identification.

Occupational allergy to aquarium fish food: red midge larva, freshwater shrimp, and earthworm. A clinical and immunological study.

PubMed

Meseguer Arce, J; Villajos, I M Sánchez-Guerrero; Iraola, V; Carnés, J; Fernández Caldas, E

2013-01-01

Chironomids seem to be the main cause of occupational allergy to aquarium fish food. The aim of this study was to investigate the pattern of occupational sensitization to 3 different arthropod species used as components of aquarium fish food. The study sample comprised 8 workers from a fish food packing department. The control group comprised 40 atopic patients (20 of whom were allergic to mites). We performed prick tests with extracts of red midge larva (Chironomus thummi), freshwater shrimp (Gammarus species), earthworm (Tubifex species), and other arthropod species and a battery of common inhalant allergens. We measured peak expiratory flow rate (PEFR) and specific immunoglobulin (Ig) E and performed a methacholine challenge test, nasal challenge test, and immunoblotting. Cross-reactivity analyses were completed using immunoblotting and CAP inhibition. Prick test results were positive to red midge larvae in 7 patients (87.5%), Gammarus in 5 (62.5%), Tubifex in 3 (37.5%), and mites in 6 (75%). In the mite-allergic controls, 30% had positive prick test results to red midge larvae. PEFR decreased > or = 20% during the packing process in all patients, and in 1 patient it indicated a dual asthmatic response. Methacholine challenge test results were positive in all participants. Nasal challenge tests were performed in 4 patients, and the results were positive. Specific IgE to red midge larvae was detected in 62.5%, Gammarus in 50%, and Tubifex in 16%. Bands of approximately 14-15 kDa and 31 kDa were observed in Gammarus and red midge larvae extracts. Cross-reactivity assays demonstrated that Gammarus totally inhibited red midge larvae, while Tubifex did so partially. Dermatophagoides pteronyssinus showed very low inhibitory capacity. Aquarium fish food arthropods are potent allergens with an elevated prevalence of sensitization and variable degree of crossreactivity. This is the first report of occupational allergy to Tubifex. More data are necessary to identify and characterize the responsible allergens.

Fabrication and testing of U–7Mo monolithic plate fuel with Zircaloy cladding

DOE PAGES

Pasqualini, E. E.; Robinson, A. B.; Porter, D. L.; ...

2016-07-15

The Materials Management and Minimization program is developing fuel designs to replace highly enriched fuel with fuels of low enrichment. In the most challenging cases, U–(7–10wt%)Mo monolithic plate fuel are proposed. The chosen design includes aluminum-alloy cladding, which provides some challenges in fabrication and fuel/cladding interaction in service. We investigated zircaloy cladding, specifically Zry–4as an alternative cladding, and development of a fabrication method was performed by researchers with the Comisión Nacionalde Energia Atómica (CNEA) in Argentina, resulting in test fuel plates (Zry–4 clad U–7Mo) which were subsequently tested in the Advanced Test Reactor in Idaho. Because Zry–4 and U–(7–10)Mo havemore » similar high-temperature mechanical properties, fabrication was simplified in that the fuel foil and cladding could be co-rolled and bonded. The challenge was to prevent a thermal-expansion mismatch which could destroy the fuel/cladding bond before complete bonding was achieved; the solution was to prevent the composites from cooling significantly between roll passes. Our final product performed very well in-reactor, showing good bonding, very little fuel/cladding interaction, either from fabrication or in-reactor testing, and little swelling, especially no detectable heterogeneous bubble formation at the fuel/cladding interface tested to a fission density of up to 2.54E+21« less

Sequential Design of Experiments to Maximize Learning from Carbon Capture Pilot Plant Testing

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

Soepyan, Frits B.; Morgan, Joshua C.; Omell, Benjamin P.

Pilot plant test campaigns can be expensive and time-consuming. Therefore, it is of interest to maximize the amount of learning and the efficiency of the test campaign given the limited number of experiments that can be conducted. This work investigates the use of sequential design of experiments (SDOE) to overcome these challenges by demonstrating its usefulness for a recent solvent-based CO2 capture plant test campaign. Unlike traditional design of experiments methods, SDOE regularly uses information from ongoing experiments to determine the optimum locations in the design space for subsequent runs within the same experiment. However, there are challenges that needmore » to be addressed, including reducing the high computational burden to efficiently update the model, and the need to incorporate the methodology into a computational tool. We address these challenges by applying SDOE in combination with a software tool, the Framework for Optimization, Quantification of Uncertainty and Surrogates (FOQUS) (Miller et al., 2014a, 2016, 2017). The results of applying SDOE on a pilot plant test campaign for CO2 capture suggests that relative to traditional design of experiments methods, SDOE can more effectively reduce the uncertainty of the model, thus decreasing technical risk. Future work includes integrating SDOE into FOQUS and using SDOE to support additional large-scale pilot plant test campaigns.« less

Fabrication and testing of U–7Mo monolithic plate fuel with Zircaloy cladding

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

Pasqualini, E. E.; Robinson, A. B.; Porter, D. L.

The Materials Management and Minimization program is developing fuel designs to replace highly enriched fuel with fuels of low enrichment. In the most challenging cases, U–(7–10wt%)Mo monolithic plate fuel are proposed. The chosen design includes aluminum-alloy cladding, which provides some challenges in fabrication and fuel/cladding interaction in service. We investigated zircaloy cladding, specifically Zry–4as an alternative cladding, and development of a fabrication method was performed by researchers with the Comisión Nacionalde Energia Atómica (CNEA) in Argentina, resulting in test fuel plates (Zry–4 clad U–7Mo) which were subsequently tested in the Advanced Test Reactor in Idaho. Because Zry–4 and U–(7–10)Mo havemore » similar high-temperature mechanical properties, fabrication was simplified in that the fuel foil and cladding could be co-rolled and bonded. The challenge was to prevent a thermal-expansion mismatch which could destroy the fuel/cladding bond before complete bonding was achieved; the solution was to prevent the composites from cooling significantly between roll passes. Our final product performed very well in-reactor, showing good bonding, very little fuel/cladding interaction, either from fabrication or in-reactor testing, and little swelling, especially no detectable heterogeneous bubble formation at the fuel/cladding interface tested to a fission density of up to 2.54E+21« less

"It Can Promote an Existential Crisis": Factors Influencing Pap Test Acceptability and Utilization Among Transmasculine Individuals.

PubMed

Peitzmeier, Sarah M; Agénor, Madina; Bernstein, Ida M; McDowell, Michal; Alizaga, Natalie M; Reisner, Sari L; Pardee, Dana J; Potter, Jennifer

2017-12-01

Transmasculine (i.e., female-to-male transgender) individuals have lower rates of cervical cancer screening than nontransgender women and often report negative experiences with the Pap test. Deciding to undergo screening and the test experience itself are characterized by the following processes: negotiating identity as the patient, provider, and insurance company wrestle with the degree of (in)congruence between a patient's masculine gender identity and their conception of the Pap test as feminine; bargaining for health as a Pap test may be required to obtain medical transition services or avoid undesired health outcomes; withstanding acute challenges during the Pap test to body, identity, and privacy; or reframing challenges as affirmation. The degree of distress triggered by the Pap test varied from "routine" to traumatic. Participants affirmed that a trusted, trans-competent health care provider could significantly reduce barriers to regular and satisfactory cervical cancer screening. Data are from 32 in-depth interviews conducted in Boston, Massachusetts, with transmasculine individuals; a modified grounded theory approach informed the analysis.

DEVELOPMENT, DESIGN AND CONSUMER TESTING OF MARKETABLE RESIDENTIAL LED LIGHT LUMINAIRES

EPA Science Inventory

Developing marketable LED luminaires poses challenges, even though LEDs are energy-efficient and an ecological alternative to conventionally lighting. Challenges include: perceptions that the color rendition of LEDs is unacceptable to the public; numbers of LEDs must be grou...

Assessing EDCs in the Field: Challenges and New Approaches

EPA Science Inventory

Assessing the occurrence and effects of EDCs in the environment can be challenging from a number of perspectives. For example, conventional analytical approaches and/or toxicity tests may not be appropriate to detecting very potent chemicals that impact specific pathways, and oft...

Testing Like William the Conqueror: Cultural and Instrumental Uses of Examinations

ERIC Educational Resources Information Center

Dorn, Sherman

2014-01-01

The spread of academic testing for accountability purposes in multiple countries has obscured at least two historical purposes of academic testing: community ritual and management of the social structure. Testing for accountability is very different from the purpose of academic challenges one can identify in community "examinations" in…

Test Fairness and Toulmin's Argument Structure

ERIC Educational Resources Information Center

Kunnan, Antony John

2010-01-01

This paper presents the author's response to Xiaoming Xi's article titled "How do we go about investigating test fairness?" In this response, the author focuses on test fairness and Toulmin's model of argument structure, Xi's proposal, and the challenges the proposal brings. Xi proposes an approach to investigating test fairness to guide…

Culturally Sensitive Career Assessment: A Quandary. ERIC Digest No. 210.

ERIC Educational Resources Information Center

Austin, James T.

Multicultural perspectives on assessment challenge traditional perspectives by advancing an additional source of variation in test responses that is presumed to escape test developers and test users. Increasing and convergent evidence from multiple sources indicates the following types of ethnocentric errors in test development, administration,…

EALUATION OF COGNITIVE FUNCTION IN WEANLING RATS: A REVIEW OF METHODS SUITABLE FOR CHEMICAL SCREENING

EPA Science Inventory

Current developmental neurotoxicity (DNT) tests that are used for environmental agents call for cognitive testing around the age of weaning as well as adulthood. There are challenges associated with testing weanling rodents that are not present with testing older subjects, inclu...

Towards a Rigorous Assessment of Systems Biology Models: The DREAM3 Challenges

PubMed Central

Prill, Robert J.; Marbach, Daniel; Saez-Rodriguez, Julio; Sorger, Peter K.; Alexopoulos, Leonidas G.; Xue, Xiaowei; Clarke, Neil D.; Altan-Bonnet, Gregoire; Stolovitzky, Gustavo

2010-01-01

Background Systems biology has embraced computational modeling in response to the quantitative nature and increasing scale of contemporary data sets. The onslaught of data is accelerating as molecular profiling technology evolves. The Dialogue for Reverse Engineering Assessments and Methods (DREAM) is a community effort to catalyze discussion about the design, application, and assessment of systems biology models through annual reverse-engineering challenges. Methodology and Principal Findings We describe our assessments of the four challenges associated with the third DREAM conference which came to be known as the DREAM3 challenges: signaling cascade identification, signaling response prediction, gene expression prediction, and the DREAM3 in silico network challenge. The challenges, based on anonymized data sets, tested participants in network inference and prediction of measurements. Forty teams submitted 413 predicted networks and measurement test sets. Overall, a handful of best-performer teams were identified, while a majority of teams made predictions that were equivalent to random. Counterintuitively, combining the predictions of multiple teams (including the weaker teams) can in some cases improve predictive power beyond that of any single method. Conclusions DREAM provides valuable feedback to practitioners of systems biology modeling. Lessons learned from the predictions of the community provide much-needed context for interpreting claims of efficacy of algorithms described in the scientific literature. PMID:20186320

Evaluation of the performance and response of the bacharach TLV sniffer and H-Nu photoionization gas analyzer to common hydrocarbon solvents.

PubMed

Chelton, C F; Zakraysek, N; Lautner, G M; Confer, R G

1983-10-01

Two direct reading instruments, the H-Nu PI 101 photoionization analyzer and the J.W. Bacharach TLV Sniffer, were evaluated under laboratory conditions to determine their performance characteristics when challenged by vapors of common hydrocarbon solvent mixtures. Each instrument was evaluated against the manufacturer's recommended test solvent for rise time, fall time, noise, span drift, zero drift, position sensitivity, battery life, and recharge time. The precision, accuracy, and operating linear range were also determined for the test solvents and some petroleum solvent mixtures which are common refinery products. For these latter mixtures, correction factors are presented which allow for an improved estimate of ambient concentrations when monitoring with each of these instruments. All tests except operating humidity range were performed by challenging each instrument with a known concentration of hydrocarbon generated by evaporating calculated liquid volumes into a static chamber. Humidity tests were performed using a dynamic dilution apparatus generating a fixed concentration of hydrocarbon while relative humidity was varied. Concentrations in both systems were verified by gas injection into gas chromatograph. Each instrument performed well when challenged by manufacturers' recommended test solvents. Humidity was shown to influence each instrument's readings. Also, the instruments were shown to have application as monitors of airborne concentrations of common hydrocarbon solvent mixtures.

Fabrication and testing of U-7Mo monolithic plate fuel with Zircaloy cladding

NASA Astrophysics Data System (ADS)

Pasqualini, E. E.; Robinson, A. B.; Porter, D. L.; Wachs, D. M.; Finlay, M. R.

2016-10-01

Nuclear fuel designs are being developed to replace highly enriched fuel used in research and test reactors with fuels of low enrichment. In the most challenging cases, U-(7-10 wt%)Mo monolithic plate fuels are proposed. One of the considered designs includes aluminum-alloy cladding, which provides some challenges in fabrication and fuel/cladding interaction during service. Zircaloy cladding, specifically Zry-4, was investigated as an alternative cladding, and development of a fabrication method was performed by researchers with the Comisión Nacionalde Energia Atómica (CNEA) in Argentina, resulting in test fuel plates (Zry-4 clad U-7Mo) which were subsequently tested in the Advanced Test Reactor in Idaho. Because Zry-4 and U-(7-10)Mo have similar high-temperature mechanical properties, fabrication was simplified in that the fuel foil and cladding could be co-rolled and bonded. The challenge was to prevent a thermal-expansion mismatch, which could destroy the fuel/cladding bond before complete bonding was achieved; the solution was to prevent the composites from cooling significantly during or between roll passes. The final product performed very well in-reactor, showing good bonding, very little fuel/cladding interaction-either from fabrication or in-reactor testing-and little swelling, especially no detectable heterogeneous bubble formation at the fuel/cladding interface tested to a fission density of up to 2.7E+21 (average) fissions/cm3, 3.8E+21 (peak).

International collaborative studies on potency assays of diphtheria and tetanus toxoids.

PubMed

Van Ramshorst, J D; Sundaresan, T K; Outschoorn, A S

1972-01-01

Collaborative studies showed that relative potency assays for a particular type of diphtheria toxoid (adsorbed) and for tetanus toxoid (plain and adsorbed) gave very similar results, whether the assays were carried out by toxin challenge or by antitoxin titration after immunization of experimental animals with graded doses of toxoid. The same numerical results were obtained with a scoring system as with a system based on survivals only. Although skin tests were used on a very limited scale in these studies, it seems likely that they could replace lethal tests for the diphtheria challenge assays.For both tetanus and diphtheria, the adsorbed toxoid gave a higher relative potency when combined with other antigens than as a single toxoid. Both mice and guinea-pigs were used for the lethal challenge test of adsorbed tetanus toxoid. For the single tetanus toxoid the results were the same, but for the combined toxoid (DPT vaccine) the mouse assay results were about twice those of guinea-pig assays.

International collaborative studies on potency assays of diphtheria and tetanus toxoids

PubMed Central

van Ramshorst, J. D.; Sundaresan, T. K.; Outschoorn, A. S.

1972-01-01

Collaborative studies showed that relative potency assays for a particular type of diphtheria toxoid (adsorbed) and for tetanus toxoid (plain and adsorbed) gave very similar results, whether the assays were carried out by toxin challenge or by antitoxin titration after immunization of experimental animals with graded doses of toxoid. The same numerical results were obtained with a scoring system as with a system based on survivals only. Although skin tests were used on a very limited scale in these studies, it seems likely that they could replace lethal tests for the diphtheria challenge assays. For both tetanus and diphtheria, the adsorbed toxoid gave a higher relative potency when combined with other antigens than as a single toxoid. Both mice and guinea-pigs were used for the lethal challenge test of adsorbed tetanus toxoid. For the single tetanus toxoid the results were the same, but for the combined toxoid (DPT vaccine) the mouse assay results were about twice those of guinea-pig assays. PMID:4537488

CHALLENGES IN SETTING UP QUALITY CONTROL IN DIAGNOSTIC RADIOLOGY FACILITIES IN NIGERIA.

PubMed

Inyang, S O; Egbe, N O; Ekpo, E

2015-01-01

The Nigerian Nuclear Regulatory Authority (NNRA) was established to regulate and control the use of radioactive and radiation emitting sources in Nigeria. Quality control (QC) on diagnostic radiology equipment form part of the fundamental requirements for the authorization of diagnostic radiology facilities in the Country. Some quality control tests (output, exposure linearity and reproducibility) were measured on the x-ray machines in the facilities that took part in the study. Questionnaire was developed to evaluate the frequencies at which QC tests were conducted in the facilities and the challenges in setting up QC. Results show great variation in the values of the QC parameters measured. Inadequate cooperation by facilities management, lack of QC equipment and insufficient staff form the major challenges in setting up QC in the facilities under study. The responses on the frequencies at which QC tests should be conducted did not correspond to the recommended standards; indicating that personnel were not familiar with QC implementation and may require further training on QC.

Ability evaluation by binary tests: Problems, challenges & recent advances

NASA Astrophysics Data System (ADS)

Bashkansky, E.; Turetsky, V.

2016-11-01

Binary tests designed to measure abilities of objects under test (OUTs) are widely used in different fields of measurement theory and practice. The number of test items in such tests is usually very limited. The response to each test item provides only one bit of information per OUT. The problem of correct ability assessment is even more complicated, when the levels of difficulty of the test items are unknown beforehand. This fact makes the search for effective ways of planning and processing the results of such tests highly relevant. In recent years, there has been some progress in this direction, generated by both the development of computational tools and the emergence of new ideas. The latter are associated with the use of so-called “scale invariant item response models”. Together with maximum likelihood estimation (MLE) approach, they helped to solve some problems of engineering and proficiency testing. However, several issues related to the assessment of uncertainties, replications scheduling, the use of placebo, as well as evaluation of multidimensional abilities still present a challenge for researchers. The authors attempt to outline the ways to solve the above problems.

A study to assess whether fixed-width beam walking provides sufficient challenge to assess balance ability across lower limb prosthesis users.

PubMed

Sawers, Andrew; Hafner, Brian J

2018-04-01

To evaluate the feasibility of fixed-width beam walking for assessing balance in lower limb prosthesis users. Cross-sectional. Laboratory. Lower limb prosthesis users. Participants attempted 10 walking trials on three fixed-width beams (18.6, 8.60, and 4.01 wide; 5.5 m long; 3.8 cm high). Beam-walking performance was quantified using the distance walked to balance failure. Heuristic rules applied to each participant's beam-walking distance to classify each beam as "too easy," "too hard," or "appropriately challenging" and determine whether any single beam provided an appropriate challenge to all participants. The number of trials needed to achieve stable beam-walking performance was quantified for appropriately challenging beams by identifying the last inflection point in the slope of each participant's trial-by-trial cumulative performance record. In all, 30 unilateral lower limb prosthesis users participated in the study. Each of the fixed-width beams was either too easy or too hard for at least 33% of the sample. Thus, no single beam was appropriately challenging for all participants. Beam-walking performance was stable by trial 8 for all participants and by trial 6 for 90% of participants. There was no significant difference in the number of trials needed to achieve stable performance among beams ( P = 0.74). Results suggest that a clinical beam-walking test would require multiple beams to evaluate balance across a range of lower limb prosthesis users, emphasizing the need for adaptive or progressively challenging balance tests. While the administrative burden of a multiple-beam balance test may limit clinical feasibility, alternatives to ease this administrative burden are proposed.

Commercialisation of Biomarker Tests for Mental Illnesses: Advances and Obstacles.

PubMed

Chan, Man K; Cooper, Jason D; Bahn, Sabine

2015-12-01

Substantial strides have been made in the field of biomarker research for mental illnesses over the past few decades. However, no US FDA-cleared blood-based biomarker tests have been translated into routine clinical practice. Here, we review the challenges associated with commercialisation of research findings and discuss how these challenges can impede scientific impact and progress. Overall evidence indicates that a lack of research funding and poor reproducibility of findings were the most important obstacles to commercialization of biomarker tests. Fraud, pre-analytical and analytical limitations, and inappropriate statistical analysis are major contributors to poor reproducibility. Increasingly, these issues are acknowledged and actions are being taken to improve data validity, raising the hope that robust biomarker tests will become available in the foreseeable future. Copyright © 2015 Elsevier Ltd. All rights reserved.

Clinical Uncertainties, Health Service Challenges, and Ethical Complexities of HIV “Test-and-Treat”: A Systematic Review

PubMed Central

Shah, Kavita R.; Sarma, Karthik V.; Mahajan, Anish P.

2013-01-01

Despite the HIV “test-and-treat” strategy’s promise, questions about its clinical rationale, operational feasibility, and ethical appropriateness have led to vigorous debate in the global HIV community. We performed a systematic review of the literature published between January 2009 and May 2012 using PubMed, SCOPUS, Global Health, Web of Science, BIOSIS, Cochrane CENTRAL, EBSCO Africa-Wide Information, and EBSCO CINAHL Plus databases to summarize clinical uncertainties, health service challenges, and ethical complexities that may affect the test-and-treat strategy’s success. A thoughtful approach to research and implementation to address clinical and health service questions and meaningful community engagement regarding ethical complexities may bring us closer to safe, feasible, and effective test-and-treat implementation. PMID:23597344

Biomarker Testing for Personalized Therapy in Lung Cancer in Low- and Middle-Income Countries.

PubMed

Hirsch, Fred R; Zaric, Bojan; Rabea, Ahmed; Thongprasert, Sumitra; Lertprasertsuke, Nirush; Dalurzo, Mercedes Liliana; Varella-Garcia, Marileila

2017-01-01

There have been many important advances in personalized therapy for patients with lung cancer, particularly for those with advanced disease. Molecular testing is crucial for implementation of personalized therapy. Although the United States and many Western countries have come far in the implementation of personalized therapy for lung cancer, there are substantial challenges for low- and middle-income countries (LMICs). Globally, the LMICs display great heterogeneity in the pattern of implementation of molecular testing and targeted therapy. The current review presents an attempt to identify the challenges and obstacles for the implementation of molecular testing and the use of targeted therapies in these areas. Lack of infrastructure, lack of technical expertise, economic factors, and lack of access to new drugs are among the substantial barriers.

Diagnosis of food allergies: the impact of oral food challenge testing.

PubMed

Ito, Komei

2013-01-01

A diagnosis of food allergies should be made based on the observation of allergic symptoms following the intake of suspected foods and the presence of allergen-specific IgE antibodies. The oral food challenge (OFC) test is the most reliable clinical procedure for diagnosing food allergies. Specific IgE testing of allergen components as well as classical crude allergen extracts helps to make a more specific diagnosis of food allergies. The Japanese Society of Pediatric Allergy and Clinical Immunology issued the 'Japanese Pediatric Guideline for Food Allergy 2012' to provide information regarding the standardized diagnosis and management of food allergies. This review summarizes recent progress in the diagnosis of food allergies, focusing on the use of specific IgE tests and the OFC procedure in accordance with the Japanese guidelines.

Immune tolerance to drugs. I. Long-term tolerability of rokitamycin in patients with antibiotics hypersensitivity.

PubMed

Nettis, E; Colanardi, M C; Di Paola, R; Mangialardi, G; Ferrannini, A; Tursi, A

2003-08-01

Macrolides are considered one of the safest anti-infective groups in clinical use and are well-tolerated as alternative antibiotics in patients with a previous adverse reaction to other classes of antibiotics. However there is scarce information in the literature about their long-term tolerability. The present study was performed to determine whether the results of a challenge test with rokitamycin could predict the response to ingestion of rokitamycin during illness. The study was carried out on 335 patients, who experienced adverse reactions to one or more antibiotics. All patients received peroral challenges with rokitamycin (granules or capsules). On the first day patients received a number of placebo doses equivalent to the rokitamycin doses. One week later, the test was administered by increasing doses of rokitamycin at 60 min intervals until the common daily therapeutic dose of 406.25mg was reached (31.25-93.75-125-156.25mg). A questionnaire was distributed to all subjects. In particular, subjects were asked to clarify any reactive symptom they had developed after ingestion of the drug. It was found that only 3.1% (4/129) of subjects, who used this drug, reported adverse reactions: three experienced urticaria/angioedema and one patient experienced erythema multiforme during treatment. This study, points out a low percentage of adverse reactions to rokitamycin after a negative challenge test, thus, emphasizing both safety and good predictive value as a challenge test.

Blood DNA methylation biomarkers predict clinical reactivity in food-sensitized infants.

PubMed

Martino, David; Dang, Thanh; Sexton-Oates, Alexandra; Prescott, Susan; Tang, Mimi L K; Dharmage, Shyamali; Gurrin, Lyle; Koplin, Jennifer; Ponsonby, Anne-Louise; Allen, Katrina J; Saffery, Richard

2015-05-01

The diagnosis of food allergy (FA) can be challenging because approximately half of food-sensitized patients are asymptomatic. Current diagnostic tests are excellent makers of sensitization but poor predictors of clinical reactivity. Thus oral food challenges (OFCs) are required to determine a patient's risk of reactivity. We sought to discover genomic biomarkers of clinical FA with utility for predicting food challenge outcomes. Genome-wide DNA methylation (DNAm) profiling was performed on blood mononuclear cells from volunteers who had undergone objective OFCs, concurrent skin prick tests, and specific IgE tests. Fifty-eight food-sensitized patients (aged 11-15 months) were assessed, half of whom were clinically reactive. Thirteen nonallergic control subjects were also assessed. Reproducibility was assessed in an additional 48 samples by using methylation data from an independent population of patients with clinical FA. Using a supervised learning approach, we discovered a DNAm signature of 96 CpG sites that predict clinical outcomes. Diagnostic scores were derived from these 96 methylation sites, and cutoffs were determined in a sensitivity analysis. Methylation biomarkers outperformed allergen-specific IgE and skin prick tests for predicting OFC outcomes. FA status was correctly predicted in the replication cohort with an accuracy of 79.2%. DNAm biomarkers with clinical utility for predicting food challenge outcomes are readily detectable in blood. The development of this technology in detailed follow-up studies will yield highly innovative diagnostic assays. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Using the Rasch Model to Determine Equivalence of Forms In the Trilingual Lollipop Readiness Test

ERIC Educational Resources Information Center

Lang, W. Steve; Chew, Alex L.; Crownover, Carol; Wilkerson, Judy R.

2007-01-01

Determining the cross-cultural equivalence of multilingual tests is a challenge that is more complex than simple horizontal equating of test forms. This study examines the functioning of a trilingual test of preschool readiness to determine the equivalence. Different forms of the test have previously been examined using classical statistical…

Legal Challenges to Testing--Larry P.: A Case in Point.

ERIC Educational Resources Information Center

Lambert, Nadine M.

Several major issues were raised against intelligence testing by the plaintiffs in Larry P. versus Wilson Riles. It was argued that since California used intelligence tests to ascertain who should be placed in programs for the educable mentally retarded (EMR), and since blacks performed less well on the tests than whites, it was the tests which…

Measuring College Students' Reading Comprehension Ability Using Cloze Tests

ERIC Educational Resources Information Center

Williams, Rihana Shiri; Ari, Omer; Santamaria, Carmen Nicole

2011-01-01

Recent investigations challenge the construct validity of sustained silent reading tests. Performance of two groups of post-secondary students (e.g. struggling and non-struggling) on a sustained silent reading test and two types of cloze test (i.e. maze and open-ended) was compared in order to identify the test format that contributes greater…

Effects of Concept Map Extraction and a Test-Based Diagnostic Environment on Learning Achievement and Learners' Perceptions

ERIC Educational Resources Information Center

Lin, Yu-Shih; Chang, Yi-Chun; Liew, Keng-Hou; Chu, Chih-Ping

2016-01-01

Computerised testing and diagnostics are critical challenges within an e-learning environment, where the learners can assess their learning performance through tests. However, a test result based on only a single score is insufficient information to provide a full picture of learning performance. In addition, because test results implicitly…

Test Equity for Individuals Who Are Deaf or Hard of Hearing. PEPNet Test Equity Summit

ERIC Educational Resources Information Center

PEPNet-West, 2010

2010-01-01

This paper presents the highlights of the 2008 Test Equity Summit held in Bloomfield, Colorado last August 6-8, 2008. The 2008 Test Equity Summit convened by the Postsecondary Education Programs Network (PEPNet) identified and examined problems, challenges, and issues that academic and psychoeducational tests pose for individuals who are deaf or…

Cross-species extrapolation of chemical effects: Challenges and new insights

EPA Science Inventory

One of the greatest uncertainties in chemical risk assessment is extrapolation of effects from tested to untested species. While this undoubtedly is a challenge in the human health arena, species extrapolation is a particularly daunting task in ecological assessments, where it is...

Commentary: Pediatric eHealth Interventions: Common Challenges During Development, Implementation, and Dissemination

PubMed Central

Steele, Ric G.; Connelly, Mark A.; Palermo, Tonya M.; Ritterband, Lee M.

2014-01-01

Objective To provide an overview of common challenges that pediatric eHealth researchers may encounter when planning, developing, testing, and disseminating eHealth interventions along with proposed solutions for addressing these challenges. Methods The article draws on the existing eHealth literature and the authors’ collective experience in pediatric eHealth research. Results and conclusions The challenges associated with eHealth interventions and their proposed solutions are multifaceted and cut across a number of areas from eHealth program development through dissemination. Collaboration with a range of individuals (e.g., multidisciplinary colleagues, commercial entities, primary stakeholders) is the key to eHealth intervention success. To ensure adequate resources for design, development, and planning for sustainability, a number of public and private sources of funding are available. A study design that addresses ethical concerns and security issues is critical to ensure scientific integrity and intervention dissemination. Table I summarizes key issues to consider during eHealth intervention development, testing, and dissemination. PMID:24816766

Radiation Testing and Evaluation Issues for Modern Integrated Circuits

NASA Technical Reports Server (NTRS)

LaBel, Kenneth A.; Cohn, Lew M.

2005-01-01

Abstract. Changes in modern integrated circuit (IC) technologies have modified the way we approach and conduct radiation tolerance and testing of electronics. These changes include scaling of geometries, new materials, new packaging technologies, and overall speed and device complexity challenges. In this short course section, we will identify and discuss these issues as they impact radiation testing, modeling, and effects mitigation of modern integrated circuits. The focus will be on CMOS-based technologies, however, other high performance technologies will be discussed where appropriate. The effects of concern will be: Single-Event Effects (SEE) and steady state total ionizing dose (TID) IC response. However, due to the growing use of opto-electronics in space systems issues concerning displacement damage testing will also be considered. This short course section is not intended to provide detailed "how-to-test" information, but simply provide a snapshot of current challenges and some of the approaches being considered.

Need for new technologies for detection of adventitious agents in vaccines and other biological products.

PubMed

Mallet, Laurent; Gisonni-Lex, Lucy

2014-01-01

From an industrial perspective, the conventional in vitro and in vivo assays used for detection of viral contaminants have shown their limitations, as illustrated by the unfortunate detection of porcine circovirus contamination in a licensed rotavirus vaccine. This contamination event illustrates the gaps within the existing adventitious agent strategy and the potential use of new broader molecular detection methods. This paper serves to summarize current testing approaches and challenges, along with opportunities for the use of these new technologies. Testing of biological products is required to ensure the safety of patients. Recently, a licensed vaccine was found to be contaminated with a virus. This contamination did not cause a safety concern to the patients; however, it highlights the need for using new testing methods to control our biological products. This paper introduces the benefits of these new tests and outlines the challenges with the current tests. © PDA, Inc. 2014.

Cross refractoriness between sodium metabisulphite and exercise induced asthma.

PubMed Central

Pavord, I.; Lazarowicz, H.; Inchley, D.; Baldwin, D.; Knox, A.; Tattersfield, A.

1994-01-01

BACKGROUND--Exercise and inhaled sodium metabisulphite are thought to cause bronchoconstriction in asthma through different mechanisms. The response to both stimuli becomes refractory with repeat challenge. The mechanism of refractoriness is unclear, although depletion of mast cell derived mediators or neurotransmitters has been suggested. Recent studies suggest a common mechanism involving release of inhibitory prostaglandins. If this is true, exercise and sodium metabisulphite induced bronchoconstriction should show cross refractoriness. METHODS--Thirteen subjects with mild asthma and previously established exercise and sodium metabisulphite induced bronchoconstriction performed two sodium metabisulphite challenges (giving a single dose previously shown to cause a 20% fall in FEV1) on one study day, and two exercise tests on another. The second challenge proceeded after recovery (FEV1 > 95% baseline) from the first. Subjects then attended on two further occasions when an exercise test was performed after sodium metabisulphite and a sodium metabisulphite challenge after exercise. RESULTS--When expressed as the percentage reduction in the area under the change in percentage FEV1 curve over 20 minutes (AUC) the response to exercise was reduced by a mean 62.3% (95% CI 46.5% to 78.1%) following a first exercise challenge, and by 50.7% (95% CI 27.8% to 73.6%) following a sodium metabisulphite challenge. The response to a sodium metabisulphite challenge was reduced by a mean of 80.2% (95% CI 68.9% to 91.5%) when it followed a sodium metabisulphite challenge, and by 37.3% (95% CI 15.1% to 59.5%) following an exercise challenge. CONCLUSION--This study shows some cross refractoriness between exercise and sodium metabisulphite induced bronchoconstriction, in keeping with a partially shared mechanism of refractoriness. PMID:8202881

Predicting food challenge outcomes for baked milk: role of specific IgE and skin prick testing.

PubMed

Bartnikas, Lisa M; Sheehan, William J; Hoffman, Elaine B; Permaul, Perdita; Dioun, Anahita F; Friedlander, James; Baxi, Sachin N; Schneider, Lynda C; Phipatanakul, Wanda

2012-11-01

Cow's milk allergy is the most common food allergy in childhood. Many children with IgE-mediated cow's milk allergy may tolerate baked milk products, but few data exist on predictors of outcomes of baked milk challenges. To determine the relation of milk protein allergen specific IgE (sIgE) levels and skin prick test (SPT) wheal size with baked milk challenge outcomes. A retrospective medical record review was conducted of 35 baked milk challenges. SPT results, sIgE levels, demographic characteristics, and food challenge results were analyzed. Thirty-five children underwent open challenges to baked milk and 29 (83%) passed. Of those who failed, 3 (50%) passed the initial clinic challenge but developed symptoms to ongoing exposure at home, days to months later. One child who ultimately failed at home required epinephrine. Compared with those who passed, children who failed were younger (median age, 8.9 and 3.7 years, respectively; P = .02). Children with a milk SPT wheal less than 12 mm were more than 90% likely to pass a baked milk challenge, and no child with a milk SPT wheal less than 7 mm failed a baked milk challenge. We were also able to establish more than 90% predictive values for passing baked milk challenges with a casein SPT wheal of 9 mm, a milk sIgE level of 1.0 kU/L, and a casein sIgE level of 0.9 kU/L. Most children allergic to cow's milk tolerated baked milk. Milk protein SPT wheal may be more reliable than sIgE level in predicting outcomes of baked milk challenges. It is important to be aware of the possibility of late reactions to ongoing baked milk exposure. Copyright © 2012 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Diagnosis of Ebola Virus Disease: Past, Present, and Future

PubMed Central

Brooks, Tim J. G.

2016-01-01

SUMMARY Laboratory diagnosis of Ebola virus disease plays a critical role in outbreak response efforts; however, establishing safe and expeditious testing strategies for this high-biosafety-level pathogen in resource-poor environments remains extremely challenging. Since the discovery of Ebola virus in 1976 via traditional viral culture techniques and electron microscopy, diagnostic methodologies have trended toward faster, more accurate molecular assays. Importantly, technological advances have been paired with increasing efforts to support decentralized diagnostic testing capacity that can be deployed at or near the point of patient care. The unprecedented scope of the 2014-2015 West Africa Ebola epidemic spurred tremendous innovation in this arena, and a variety of new diagnostic platforms that have the potential both to immediately improve ongoing surveillance efforts in West Africa and to transform future outbreak responses have reached the field. In this review, we describe the evolution of Ebola virus disease diagnostic testing and efforts to deploy field diagnostic laboratories in prior outbreaks. We then explore the diagnostic challenges pervading the 2014-2015 epidemic and provide a comprehensive examination of novel diagnostic tests that are likely to address some of these challenges moving forward. PMID:27413095

Occupational Rhinoconjunctivitis due to Maize in a Snack Processor: A Cross-Reactivity Study Between Lipid Transfer Proteins From Different Cereals and Peach.

PubMed

Guillen, Daiana; Barranco, Pilar; Palacín, Arantxa; Quirce, Santiago

2014-09-01

We report the case of a snack processor who developed occupational rhinoconjunctivitis due to maize brand exposure during the extrusion process, and who experienced abdominal pain upon drinking beer. The allergens implicated and the cross-reactivity between non-specific lipid transfer proteins (LTPs) from different cereals and peach were investigated. Skin prick tests and specific IgE to cereal flours, pulmonary functions tests and specific conjunctival and inhalation challenges to maize extract were performed. In vitro studies included IgE immunoblotting and ELISA inhibition assays. Skin prick tests with maize flour, maize brand and wheat flour extracts were positive, whereas serum specific IgE was positive only to maize flour. Specific inhalation challenge (SIC) to maize flour did not elicit an asthmatic reaction; however, conjunctival challenge test with the same extract was positive. Patient's serum recognized IgE-binding bands in the maize and beer extracts corresponding to LTPs. In the ELISA inhibition assays, a significant degree of allergenic cross-reactivity was found between maize and beer LTPs, whereas no cross-reactivity was observed between maize LTP and wheat and peach LTPs.

Narrowing beam-walking is a clinically feasible approach for assessing balance ability in lower-limb prosthesis users.

PubMed

Sawers, Andrew; Hafner, Brian J

2018-05-08

Challenging clinical balance tests are needed to expose balance deficits in lower-limb prost-hesis users. This study examined whether narrowing beam-walking could overcome conceptual and practical limitations identified in fixed-width beam-walking. Cross-sectional. Unilateral lower-limb prosthesis users. Participants walked 10 times along a low, narrowing beam. Performance was quantified using the normalized distance walked. Heuristic rules were applied to determine whether the narrowing beam task was "too easy," "too hard," or "appropriately challenging" for each participant. Linear regression and Bland-Altman plots were used to determine whether combinations of the first 5 trials could predict participants' stable beam-walking performance. Forty unilateral lower-limb prosthesis users participated. Narrowing beam-walking was appropriately challenging for 98% of participants. Performance stabilized for 93% of participants within 5 trials, while 62% were stable across all trials. The mean of trials 3-5 accurately predicted stable performance. A clinical narrowing beam-walking test is likely to challenge a range of lower-limb prosthesis users, have minimal administrative burden, and exhibit no floor or ceiling effects. Narrowing beam-walking is therefore a clinically viable method to evaluate lower-limb prosthesis users' balance ability, but requires psychometric testing before it is used to assess fall risk.

New test method for the evaluation of the preservation efficacy of soaps at very alkaline pH made by saponification.

PubMed

Témoin-Fardini, S; Servant, J; Sellam, S

2017-10-01

The aim of this study was to develop a test method to evaluate the preservation efficacy for a specific product, a very high-alkaline liquid soap (pH around 10) made by a saponification process. Several manufacturers have experienced contamination issues with these high-pH soaps despite passing a classic preservative efficacy challenge test or even a multi-inoculation challenge test. Bacteria were isolated from contaminated soaps and were identified using 16S rRNA gene sequencing. High-alkaline-pH unpreserved soaps were tested using the Thor Personal Care internal multichallenge test method (TM206) with classical microorganisms and then with the bacterial strains isolated from various contaminated soaps (TM768). Preservatives were added to these soaps and assessed for their efficacy using the newly developed test. Four different species of bacteria (Nesterenkonia lacusekhoensis, Dermacoccus sp., Halomonas sp. and Roseomonas sp.) were identified by sequencing among the contaminants of the various soaps tested. Among these, only one bacterial species, Nesterenkonia lacusekhoensis, appeared to be responsible for the specific contamination of these high-alkaline soaps. Thus, one specific wild-type strain of Nesterenkonia lacusekhoensis, named as strain 768, was used in a new multi-inoculation test (TM768). Unlike the single inoculation challenge test, the multi-inoculation test using the Nesterenkonia strain 768 was able to predict the sensitivity of a product towards this bacterium. Among the 27 different preservatives tested, 10 were able to protect the formula against contamination with this bacterium. This study enabled the development of a test method to evaluate the efficacy of preservation using a specific bacterium, Nesterenkonia lacusekhoensis, responsible for the contamination of very alkaline soaps made by saponification and identify an appropriate preservative system. © 2017 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Ares I Flight Control System Overview

NASA Technical Reports Server (NTRS)

Hall, Charles; Lee, Chong; Jackson, Mark; Whorton, Mark; West, mark; Brandon, Jay; Hall, Rob A.; Jang, Jimmy; Bedrossian, Naz; Compton, Jimmy;

Interrogating HIV integrase for compounds that bind- a SAMPL challenge

NASA Astrophysics Data System (ADS)

Peat, Thomas S.; Dolezal, Olan; Newman, Janet; Mobley, David; Deadman, John J.

2014-04-01

Tremendous gains and novel methods are often developed when people are challenged to do something new or difficult. This process is enhanced when people compete against each other-this can be seen in sport as well as in science and technology (e.g. the space race). The SAMPL challenges, like the CASP challenges, aim to challenge modellers and software developers to develop new ways of looking at molecular interactions so the community as a whole can progress in the accurate prediction of these interactions. In order for this challenge to occur, data must be supplied so the prospective test can be done. We have supplied unpublished data related to a drug discovery program run several years ago on HIV integrase for the SAMPL4 challenge. This paper describes the methods used to obtain these data and the chemistry involved.

Limited accessibility to HIV services for persons with disabilities living with HIV in Ghana, Uganda and Zambia

PubMed Central

Tun, Waimar; Okal, Jerry; Schenk, Katie; Esantsi, Selina; Mutale, Felix; Kyeremaa, Rita Kusi; Ngirabakunzi, Edson; Asiah, Hilary; McClain-Nhlapo, Charlotte; Moono, Grimond

2016-01-01

Introduction Knowledge about experiences in accessing HIV services among persons with disabilities who are living with HIV in sub-Saharan Africa is limited. Although HIV transmission among persons with disabilities in Africa is increasingly acknowledged, there is a need to bring to life the experiences and voices from persons with disabilities living with HIV to raise awareness of programme implementers and policy makers about their barriers in accessing HIV services. This paper explores how the barriers faced by persons with disabilities living with HIV impede their ability to access HIV-related services and manage their disease. Methods We conducted focus group discussions with 76 persons (41 females; 35 males) with physical, visual and/or hearing impairments who were living with HIV in Ghana, Uganda and Zambia (2012–2013). We explored challenges and facilitators at different levels (individual, psychosocial and structural) of access to HIV services. Transcripts were analyzed using a framework analysis approach. Results Persons with disabilities living with HIV encountered a wide variety of challenges in accessing HIV services. Delays in testing for HIV were common, with most waiting until they were sick to be tested. Reasons for delayed testing included challenges in getting to the health facilities, lack of information about HIV and testing, and HIV- and disability-related stigma. Barriers to HIV-related services, including care and treatment, at health facilities included lack of disability-friendly educational materials and sign interpreters, stigmatizing treatment by providers and other patients, lack of skills to provide tailored services to persons with disabilities living with HIV and physically inaccessible infrastructure, all of which make it extremely difficult for persons with disabilities to initiate and adhere to HIV treatment. Accessibility challenges were greater for women than men due to gender-related roles. Challenges were similar across the three countries. Favourable experiences in accessing HIV services were reported in Uganda and Zambia, where disability-tailored services were offered by non-governmental organizations and government facilities (Uganda only). Conclusions Persons with disabilities living with HIV encounter many challenges in accessing HIV testing and continued care and treatment services. Changes are needed at every level to ensure accessibility of HIV services for persons with disabilities. PMID:27443266