33 results on '"Plasma chemistry"'
Search Results
2. Plasmavigilance-Adverse events among US Source plasma donors.
- Author
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Schreiber GB, Becker M, Fransen M, Hershman J, Lenart J, Song G, and Simon T
- Subjects
- Adult, Age Factors, Blood Volume, Female, Humans, Hypotension etiology, Male, Phlebotomy adverse effects, Risk Factors, Sex Factors, United States, Blood Donors, Blood Specimen Collection adverse effects, Plasma chemistry
- Abstract
Background: Source plasma (SP) is the primary starting material for 87% of plasma-derived medicinal products globally. Plasmavigilance is a program designed to collect, analyze, and monitor donor adverse events (AEs) across the SP collection industry. Donor retention depends on donors having a safe and satisfactory experience. This study analyzes AE rates and SP donor characteristics that may be predictors of an AE., Study Design and Methods: Donation data for 1.1 million donors making 12,183,182 SP donations over a 4-month period were analyzed. This represented approximately 72% of the donations collected by the U.S. plasma industry. The Standard for Recording Donor Adverse Events was used for AE definitions and classifications., Results: The overall AE rate was 15.85/10
4 donations. The two AEs with the highest rates were Hypotensive and Phlebotomy events (8.32 and 5.91/104 donations, respectively). Females had higher overall AE rates than males (25.76 vs. 9.85/104 donations), and first-time donors had higher overall AE rates than repeat donors (136.66 vs. 12.37/104 donations). Weight, body mass index, age, and pre-donation estimated blood volume also were predictors of AE., Discussion: SP donors have low AE rates with 90% being events classified as Hypotensive or Phlebotomy. Special attention and mitigation strategies should be directed to donors who are young, lightweight (between 100 and 124 pounds), female, or first-time donors to further reduce the incidence of AE, continue to ensure the donor has a safe experience, and facilitate donor retention., (© 2021 Plasma Protein Therapeutics Association. Transfusion published by Wiley Periodicals LLC on behalf of AABB.)- Published
- 2021
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3. Supply and demand for plasma-derived medicinal products - A critical reassessment amid the COVID-19 pandemic.
- Author
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Hartmann J and Klein HG
- Subjects
- Biological Products blood, Biological Products isolation & purification, Blood Donors statistics & numerical data, COVID-19 blood, COVID-19 therapy, History, 21st Century, Humans, Immunization, Passive, Immunoglobulins, Intravenous blood, Immunoglobulins, Intravenous isolation & purification, Needs Assessment, Nomograms, Pandemics, Plasma chemistry, Time Factors, United States epidemiology, COVID-19 Serotherapy, Biological Products supply & distribution, Blood Banks organization & administration, Blood Banks standards, Blood Banks statistics & numerical data, Blood Banks supply & distribution, Blood Donors supply & distribution, COVID-19 epidemiology, Health Services Needs and Demand organization & administration, Health Services Needs and Demand standards, Health Services Needs and Demand statistics & numerical data
- Published
- 2020
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4. Distinct Fecal and Plasma Metabolites in Children with Autism Spectrum Disorders and Their Modulation after Microbiota Transfer Therapy.
- Author
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Kang DW, Adams JB, Vargason T, Santiago M, Hahn J, and Krajmalnik-Brown R
- Subjects
- Child, Chromatography, Liquid, Cohort Studies, Gastrointestinal Microbiome, Humans, Metabolome, United States, Autism Spectrum Disorder metabolism, Autism Spectrum Disorder therapy, Fecal Microbiota Transplantation, Feces chemistry, Plasma chemistry
- Abstract
Accumulating evidence has strengthened a link between dysbiotic gut microbiota and autism. Fecal microbiota transplant (FMT) is a promising therapy to repair dysbiotic gut microbiota. We previously performed intensive FMT called microbiota transfer therapy (MTT) for children with autism spectrum disorders (ASD) and observed a substantial improvement of gastrointestinal and behavioral symptoms. We also reported modulation of the gut microbiome toward a healthy one. In this study, we report comprehensive metabolite profiles from plasma and fecal samples of the children who participated in the MTT trial. With 619 plasma metabolites detected, we found that the autism group had distinctive metabolic profiles at baseline. Eight metabolites (nicotinamide riboside, IMP, iminodiacetate, methylsuccinate, galactonate, valylglycine, sarcosine, and leucylglycine) were significantly lower in the ASD group at baseline, while caprylate and heptanoate were significantly higher in the ASD group. MTT drove global shifts in plasma profiles across various metabolic features, including nicotinate/nicotinamide and purine metabolism. In contrast, for 669 fecal metabolites detected, when correcting for multiple hypotheses, no metabolite was significantly different at baseline. Although not statistically significant, p -cresol sulfate was relatively higher in the ASD group at baseline, and after MTT, the levels decreased and were similar to levels in typically developing (TD) controls. p -Cresol sulfate levels were inversely correlated with Desulfovibrio , suggesting a potential role of Desulfovibrio on p -cresol sulfate modulation. Further studies of metabolites in a larger ASD cohort, before and after MTT, are warranted, as well as clinical trials of other therapies to address the metabolic changes which MTT was not able to correct. IMPORTANCE Despite the prevalence of autism and its extensive impact on our society, no U.S. Food and Drug Administration-approved treatment is available for this complex neurobiological disorder. Based on mounting evidences that support a link between autism and the gut microbiome, we previously performed a pioneering open-label clinical trial using intensive fecal microbiota transplant. The therapy significantly improved gastrointestinal and behavioral symptoms. Comprehensive metabolomic measurements in this study showed that children with autism spectrum disorder (ASD) had different levels of many plasma metabolites at baseline compared to those in typically developing children. Microbiota transfer therapy (MTT) had a systemic effect, resulting in substantial changes in plasma metabolites, driving a number of metabolites to be more similar to those from typically developing children. Our results provide evidence that changes in metabolites are one mechanism of the gut-brain connection mediated by the gut microbiota and offer plausible clinical evidence for a promising autism treatment and biomarkers., (Copyright © 2020 Kang et al.)
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- 2020
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5. Evidence lags behind excitement over blood plasma as a coronavirus treatment.
- Author
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Ledford H
- Subjects
- Antibodies, Neutralizing immunology, Antibodies, Neutralizing therapeutic use, COVID-19, Clinical Trials as Topic standards, Compassionate Use Trials, Hemorrhagic Fever, Ebola immunology, Hemorrhagic Fever, Ebola therapy, Humans, Immunization, Passive, Pandemics, Plasma chemistry, Reproducibility of Results, United States, United States Food and Drug Administration, COVID-19 Serotherapy, Convalescence, Coronavirus Infections immunology, Coronavirus Infections therapy, Evidence-Based Medicine, Plasma immunology, Pneumonia, Viral immunology, Pneumonia, Viral therapy, Uncertainty
- Published
- 2020
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6. Determination of Cytochrome P450 Isoenzyme 2D6 (CYP2D6) Genotypes and Pharmacogenomic Impact on Primaquine Metabolism in an Active-Duty US Military Population.
- Author
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Spring MD, Sousa JC, Li Q, Darko CA, Morrison MN, Marcsisin SR, Mills KT, Potter BM, Paolino KM, Twomey PS, Moon JE, Tosh DM, Cicatelli SB, Froude JW, Pybus BS, Oliver TG, McCarthy WF, Waters NC, Smith PL, Reichard GA, and Bennett JW
- Subjects
- Administration, Oral, Adolescent, Adult, Antimalarials administration & dosage, Antimalarials pharmacokinetics, Blood Chemical Analysis, Chromatography, High Pressure Liquid, Cohort Studies, Female, Humans, Male, Mass Spectrometry, Middle Aged, Military Personnel, Phenotype, Plasma chemistry, Primaquine administration & dosage, Primaquine pharmacokinetics, United States, Urinalysis, Urine chemistry, Young Adult, Antimalarials metabolism, Cytochrome P-450 CYP2D6 genetics, Cytochrome P-450 CYP2D6 metabolism, Genotype, Primaquine metabolism
- Abstract
Background: Plasmodium vivax malaria requires a 2-week course of primaquine (PQ) for radical cure. Evidence suggests that the hepatic isoenzyme cytochrome P450 2D6 (CYP2D6) is the key enzyme required to convert PQ into its active metabolite., Methods: CYP2D6 genotypes and phenotypes of 550 service personnel were determined, and the pharmacokinetics (PK) of a 30-mg oral dose of PQ was measured in 45 volunteers. Blood and urine samples were collected, with PQ and metabolites were measured using ultraperformance liquid chromatography with mass spectrometry., Results: Seventy-six CYP2D6 genotypes were characterized for 530 service personnel. Of the 515 personnel for whom a single phenotype was predicted, 58% had a normal metabolizer (NM) phenotype, 35% had an intermediate metabolizer (IM) phenotype, 5% had a poor metabolizer (PM) phenotype, and 2% had an ultrametabolizer phenotype. The median PQ area under the concentration time curve from 0 to ∞ was lower for the NM phenotype as compared to the IM or PM phenotypes. The novel 5,6-ortho-quinone was detected in urine but not plasma from all personnel with the NM phenotype., Conclusion: The plasma PK profile suggests PQ metabolism is decreased in personnel with the IM or PM phenotypes as compared to those with the NM phenotype. The finding of 5,6-ortho-quinone, the stable surrogate for the unstable 5-hydroxyprimaquine metabolite, almost exclusively in personnel with the NM phenotype, compared with sporadic or no production in those with the IM or PM phenotypes, provides further evidence for the role of CYP2D6 in radical cure., Clinical Trials Registration: NCT02960568., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.)
- Published
- 2019
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7. Phase 2a Safety, Pharmacokinetics, and Acceptability of Dapivirine Vaginal Rings in US Postmenopausal Women.
- Author
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Chen BA, Zhang J, Gundacker HM, Hendrix CW, Hoesley CJ, Salata RA, Dezzutti CS, van der Straten A, Hall WB, Jacobson CE, Johnson S, McGowan I, Nel AM, Soto-Torres L, and Marzinke MA
- Subjects
- Aged, Anti-HIV Agents administration & dosage, Double-Blind Method, Drug-Related Side Effects and Adverse Reactions epidemiology, Female, Humans, Middle Aged, Patient Acceptance of Health Care statistics & numerical data, Placebos administration & dosage, Plasma chemistry, Pyrimidines administration & dosage, United States, Anti-HIV Agents adverse effects, Anti-HIV Agents pharmacokinetics, Contraceptive Devices, Female, Postmenopause, Pyrimidines adverse effects, Pyrimidines pharmacokinetics
- Abstract
Background: Postmenopausal women have unique sociobiological human immunodeficiency virus (HIV) risks. We evaluated the safety, pharmacokinetics, and acceptability of a microbicide dapivirine (DPV) vaginal ring (VR) versus placebo in postmenopausal women., Methods: We enrolled 96 HIV-negative postmenopausal US women in a phase 2a double-blind, randomized (3:1) trial of monthly VRs containing 25 mg DPV or placebo used continuously for 12 weeks. We assessed safety by adverse events (AEs). DPV concentrations were quantified in plasma and vaginal fluid. Steady-state concentrations were analyzed at 4, 8, and 12 weeks using repeated measures ANOVA. We assessed acceptability by self-report., Results: We found no differences in the proportion of women with related grade 2 or higher reproductive system AEs (DPV: 6/72 (8%), placebo: 3/24 (13%), P = .68) or grade 3 or higher AEs (DPV: 4/72 (6%), placebo: 0/24 (0%), P = .57). In the DPV arm, 2/72 (3%) declined to resume product use due to AEs. Median DPV concentrations in plasma (262.0 pg/mL at week 12) and vaginal fluid (40.6 ng/mg at week 12) were constant over 12 weeks and exceeded the in vitro 50% effective concentration by 5000-fold in vaginal fluid by week 4. VR acceptability was high; 84/93 (90%) "very much liked or liked" the VR., Conclusions: DPV VRs were safe, well tolerated, and acceptable in postmenopausal women. Plasma concentrations were comparable to published data on DPV use in reproductive-age women (median plasma concentration: 264 pg/mL). Given the reassuring safety and pharmacokinetic data, the DPV VR is promising for preexposure prophylaxis in postmenopausal women., Clinical Trials Registration: NCT02010593., (© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
- Published
- 2019
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8. Variability of ciprofloxacin pharmacokinetics in children: impact on dose range in sickle cell patients.
- Author
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Facchin A, Bui S, Leroux S, Nacka F, Koehl B, Maksoud E, Fayon M, and Jacqz-Aigrain E
- Subjects
- Child, Child, Preschool, Chromatography, High Pressure Liquid, Female, Humans, Infant, Infant, Newborn, Male, Metabolic Clearance Rate, Plasma chemistry, United States, Anemia, Sickle Cell, Anti-Bacterial Agents administration & dosage, Anti-Bacterial Agents pharmacokinetics, Ciprofloxacin administration & dosage, Ciprofloxacin pharmacokinetics
- Abstract
Objectives: To determine the ciprofloxacin population pharmacokinetics in paediatric patients and the impact of underlying disease and evaluate the appropriateness of current dosage regimens., Patients and Methods: Plasma concentrations of ciprofloxacin from children treated with ciprofloxacin were measured by HPLC. The pharmacokinetic population analysis was performed using NONMEM v7.2 (Icon Development Solutions, USA)., Results: Two datasets were combined and 128 plasma concentrations in 60 patients aged 5.6 years (range 0.3-18.9), treated with a median daily dose of 30.0 mg/kg (range 6.5-52.0) presenting with sickle cell disease (SCD; n = 20, 33%), haemopathy (n = 15, 25%), cystic fibrosis (CF; n = 3, 5%) and other diseases (n = 22, 37%) were analysed. Data were best described by a two-compartment model with first-order elimination. Ciprofloxacin clearance (mean ± SD) was 0.81 ± 0.30 L/h/kg, increased allometrically with weight, decreased with increasing creatinine concentration, was 89% higher in SCD compared with non-SCD patients and increased by 0.95 L/h/kg per year of age. The volume of distribution was 6.9 L/kg and depended only on the weight. Monte Carlo simulations were performed separately in SCD and non-SCD patients to target an AUC/MIC ratio >125 at steady-state, required for antibacterial efficacy, and recommendations of dosing regimens were proposed., Conclusions: In addition to known covariates, ciprofloxacin clearance is greater in SCD children compared with non-SCD patients. The dosing of this agent needs to be adapted to this subgroup of patients.
- Published
- 2018
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9. Elvitegravir/cobicistat pharmacokinetics in pregnant and postpartum women with HIV.
- Author
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Momper JD, Best BM, Wang J, Capparelli EV, Stek A, Barr E, Badell ML, Acosta EP, Purswani M, Smith E, Chakhtoura N, Park K, Burchett S, Shapiro DE, and Mirochnick M
- Subjects
- Administration, Oral, Adult, Anti-HIV Agents administration & dosage, Chromatography, Liquid, Cobicistat administration & dosage, Female, Humans, Infant, Newborn, Middle Aged, Plasma chemistry, Prospective Studies, Quinolones administration & dosage, Tandem Mass Spectrometry, United States, Young Adult, Anti-HIV Agents pharmacokinetics, Cobicistat pharmacokinetics, HIV Infections drug therapy, Postpartum Period, Pregnancy, Pregnancy Complications, Infectious drug therapy, Quinolones pharmacokinetics
- Abstract
Objective: To evaluate elvitegravir and cobicistat pharmacokinetics during pregnancy compared with postpartum and in infant washout samples after delivery., Design: Nonrandomized, open-label, parallel-group, multicenter phase-IV prospective study of antiretroviral pharmacokinetics in HIV-infected pregnant women and their children in the United States., Methods: Intensive steady-state 24-h pharmacokinetic profiles after 150 mg of elvitegravir and 150 mg of cobicistat given orally in fixed dose combination once-daily were performed during the second trimester, third trimester, and postpartum. Infant washout samples were collected after birth. Elvitegravir and cobicistat were measured in plasma by a validated liquid chromatography with tandem mass spectrometry assay with a lower quantitation limit of 10 ng/ml. A two-tailed Wilcoxon signed-rank test (α = 0.10) was employed for paired within-participant comparisons., Results: Thirty pregnant women taking elvitegravir and cobicistat once-daily enrolled in the study. Compared with paired postpartum data, elvitegravir AUC0-24 was 24% lower in the second trimester [n = 14, P = 0.058, geometric mean ratios (GMR) = 0.76, 90% confidence interval (CI) 0.57-1.0] and 44% lower in the third trimester (n = 24, P = 0.0001, GMR = 0.56, 90% CI 0.42-0.73), while cobicistat AUC0-24 was 44% lower in the second trimester (n = 14, P = 0.0085, GMR = 0.56, 90% CI 0.37-0.85) and 59% lower in the third trimester (n = 24, P < 0.0001, GMR = 0.41, 90% CI 0.30-0.57). Median cord blood elvitegravir concentration was 540.6 ng/ml and the median ratio of cord blood to maternal plasma elvitegravir concentrations was 0.91., Conclusion: Standard elvitegravir and cobicistat dosing during pregnancy results in significantly lower exposure which may increase the risk of virologic failure and mother-to-child transmission. Additional studies are needed to optimize elvitegravir and cobicistat dosing regimens in pregnant women.
- Published
- 2018
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10. Concentrations of fluoride in water and plasma for US children and adolescents: Data from NHANES 2013-2014.
- Author
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Jain RB
- Subjects
- Adolescent, Age Distribution, Child, Child, Preschool, Female, Fluorides blood, Health Surveys, Hispanic or Latino statistics & numerical data, Humans, Infant, Male, Nutrition Surveys, Sex Factors, Tobacco Smoke Pollution statistics & numerical data, United States ethnology, Fluorides analysis, Plasma chemistry, Water chemistry
- Abstract
For the first time, for 2013-2014, as part of ongoing National Health and Nutrition Examination Survey, data for fluoride concentrations in water and plasma for U.S. children and adolescents were released in the public domain. This study was undertaken to investigate how fluoride concentrations vary in water and plasma with age, gender, race/ethnicity, housing ownership, use of prescription fluoride drops and/or tablets, exposure to environmental tobacco smoke, and recent use of tobacco products (among adolescents). Fluoride concentrations in water were found to be lower among those aged 3-5 years than those aged 6-11 years (p=0.02), lower for non-Hispanic Asians than Hispanics (p=0.04) among 3-5 years old, lower for non-Hispanic Asians than non-Hispanic blacks (p=0.04) among 6-11 years old, and lower for those who used prescription fluoride drops and/or tablets than those who did not (p≤0.048) among 12-19 years old. Adjusted fluoride concentrations in plasma were found to be lower for females than males (p<0.01) among those aged 6-11 years, lower for Hispanics than non-Hispanic whites (p<0.01) among those aged 12-19 years, and lower for those who used prescription fluoride drops and/or tablets than those who did not (p=0.03) among 12-15 years old. Recent smokers were found to have higher fluoride concentration (p=0.03) in plasma than non-smoker adolescents. Over 60% of the children aged 6-11 years and adolescents aged 12-19 years were at the risk of developing dental caries/decay. About 30% of the children were at the risk of dental fluorosis., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
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11. Comparing plasma, serum and whole blood indium concentrations from workers at an indium-tin oxide (ITO) production facility.
- Author
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Harvey RR, Virji MA, Edwards NT, and Cummings KJ
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- Environmental Monitoring methods, Humans, Manufacturing and Industrial Facilities, National Institute for Occupational Safety and Health, U.S., Plasma chemistry, Serum chemistry, United States, Indium blood, Occupational Exposure analysis, Tin Compounds blood
- Abstract
Objective: Occupational exposure to indium compounds including indium-tin oxide (ITO) can result in potentially fatal indium lung disease. We compared plasma, serum and whole blood indium concentrations (In
P , InS and InB ) from workers at a single ITO production facility to assess the comparability of these matrices used for biological monitoring of indium exposure., Method: InP , InS and InB were measured using inductively coupled mass spectrometry from consenting workers at an ITO production facility with specimen collection occurring during June-July 2014. Matched pairs from workers were assessed to determine the matrix relationships using the Pearson correlation, paired t-tests, per cent difference, linear regression and κ statistics., Results: Indium matrices were collected from 80 workers. Mean (SD) InP , InS and InB were 3.48 (3.84), 3.90 (4.15) and 4.66 (5.32) mcg/L, respectively. The InS -InP difference was 14%; InS was higher in all but two workers. InP and InS were highly correlated (r=>0.99). The InB -InS difference was 19%; InB was higher in 85% of workers. The InB -InP difference was 34%; InB was higher in 66% of workers. InB was highly correlated with both InP and InS (r=0.97 and 0.96, respectively). κ Statistics were 0.84, 0.83 and 0.82 for InP , InS and InB , respectively, for individuals with each matrix ≥1 mcg/L (p<0.01)., Conclusions: While all matrices were highly correlated, we encourage the use of InP and InS to reliably compare studies across different populations using different matrices. The higher per cent difference and increased variability of InB may limit its utility in comparisons with InP and InS in different populations., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)- Published
- 2016
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12. A Preview of the 2004 Winter Conference on Plasma Spectrochemistry.
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Grégoire, D. Conrad
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- *
CONFERENCES & conventions , *SPECTRUM analysis , *PLASMA chemistry - Abstract
Presents a preview of the 2004 Winter Plasma Spectrochemistry Conference in Florida. Developments in plasma spectrochemistry and analysis; Program of activities; Projected number of attendees during the conference; Topics to be discuss. INSETS: Preliminary Program Summary;Short Courses.
- Published
- 2003
13. Treatment of multidrug-resistant Pseudomonas aeruginosa with ceftolozane/tazobactam in a critically ill patient receiving continuous venovenous haemodiafiltration.
- Author
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Kuti JL, Ghazi IM, Quintiliani R Jr, Shore E, and Nicolau DP
- Subjects
- Aged, Anti-Infective Agents, Urinary pharmacokinetics, Cephalosporins pharmacokinetics, Chromatography, High Pressure Liquid, Critical Illness, Humans, Male, Penicillanic Acid administration & dosage, Penicillanic Acid pharmacokinetics, Plasma chemistry, Pseudomonas Infections microbiology, Pseudomonas aeruginosa isolation & purification, Tazobactam, Treatment Outcome, United States, beta-Lactamase Inhibitors pharmacokinetics, Anti-Infective Agents, Urinary administration & dosage, Cephalosporins administration & dosage, Drug Resistance, Multiple, Bacterial, Hemofiltration, Penicillanic Acid analogs & derivatives, Pseudomonas Infections drug therapy, Pseudomonas aeruginosa drug effects, beta-Lactamase Inhibitors administration & dosage
- Published
- 2016
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14. Assessment of total silver and silver nanoparticle extraction from medical devices.
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Sussman EM, Jayanti P, Dair BJ, and Casey BJ
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- Humans, Materials Testing, Metal Nanoparticles analysis, Metal Nanoparticles chemistry, Metal Nanoparticles ultrastructure, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Nephelometry and Turbidimetry, Particle Size, Plasma chemistry, Rheology, Risk Assessment, Silver analysis, Silver chemistry, Sodium Chloride chemistry, Solubility, Spectrophotometry, Spectrophotometry, Atomic, Surface Properties, United States, United States Food and Drug Administration, Water chemistry, Bandages adverse effects, Catheters adverse effects, Metal Nanoparticles toxicity, Silver toxicity
- Abstract
There is concern over the release of silver nanoparticles (AgNPs) from medical devices due to their potential toxicological consequences inside the body. Towards developing the exposure component of a risk assessment model, the purpose of this study was to determine the amount and physical form of silver released from medical devices. Scanning electron microscopy was used to confirm that three of five marketed medical devices contained nanosilver coatings (mean feature sizes 115-341 nm). Aqueous device extracts (water, saline and human plasma) were analyzed with inductively coupled plasma mass spectrometry, ultraviolet-visible spectroscopy, dynamic light scattering, transmission electron microscopy, and nanoparticle tracking analysis. The amount of silver extracted from the devices ranged from 1 × 10(-1) to 1 × 10(6) ng/cm(2) (conditions ranged from 37 to 50 °C, over one hour to seven days). The results further indicated that one of the five devices (labeled MD1) released significantly more AgNPs than the other devices. This data suggests that some but not all devices that are formulated with nanosilver may release detectable levels of AgNPs upon extraction. Further work is underway to quantitate the proportion of silver released as AgNPs and to incorporate this data into a risk assessment for AgNP exposure from medical devices., (Published by Elsevier Ltd.)
- Published
- 2015
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15. Longitudinal Survey of Carotenoids in Human Milk from Urban Cohorts in China, Mexico, and the USA.
- Author
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Lipkie TE, Morrow AL, Jouni ZE, McMahon RJ, and Ferruzzi MG
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- Adult, China, Chromatography, High Pressure Liquid, Female, Humans, Infant, Infant, Newborn, Longitudinal Studies, Mexico, Middle Aged, Plasma chemistry, United States, Urban Population, Young Adult, Carotenoids analysis, Milk, Human chemistry, Postpartum Period
- Abstract
Emerging evidence indicates that carotenoids may have particular roles in infant nutrition and development, yet data on the profile and bioavailability of carotenoids from human milk remain sparse. Milk was longitudinally collected at 2, 4, 13, and 26 weeks postpartum from twenty mothers each in China, Mexico, and the USA in the Global Exploration of Human Milk Study (n = 60 donors, n = 240 samples). Maternal and neonatal plasma was analyzed for carotenoids from the USA cohort at 4 weeks postpartum. Carotenoids were analyzed by HPLC and total lipids by Creamatocrit. Across all countries and lactation stages, the top four carotenoids were lutein (median 114.4 nmol/L), β-carotene (49.4 nmol/L), β-cryptoxanthin (33.8 nmol/L), and lycopene (33.7 nmol/L). Non-provitamin A carotenoids (nmol/L) and total lipids (g/L) decreased (p<0.05) with increasing lactation stage, except the provitamin A carotenoids α- and β-cryptoxanthin and β-carotene did not significantly change (p>0.05) with lactation stage. Total carotenoid content and lutein content were greatest from China, yet lycopene was lowest from China (p<0.0001). Lutein, β-cryptoxanthin, and β-carotene, and lycopene concentrations in milk were significantly correlated to maternal plasma and neonatal plasma concentrations (p<0.05), with the exception that lycopene was not significantly associated between human milk and neonatal plasma (p>0.3). This enhanced understanding of neonatal exposure to carotenoids during development may help guide dietary recommendations and design of human milk mimetics.
- Published
- 2015
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16. Impact of body weight and missed doses on lopinavir concentrations with standard and increased lopinavir/ritonavir doses during late pregnancy.
- Author
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Cressey TR, Urien S, Capparelli EV, Best BM, Buranabanjasatean S, Limtrakul A, Rawangban B, Sabsanong P, Treluyer JM, Jourdain G, Stek A, Lallemant M, and Mirochnick M
- Subjects
- Adolescent, Adult, Anti-HIV Agents pharmacokinetics, Body Weight, Clinical Trials as Topic, Female, Humans, Lopinavir pharmacokinetics, Monte Carlo Method, Plasma chemistry, Pregnancy, Prospective Studies, Ritonavir pharmacokinetics, Thailand, Treatment Outcome, United States, Young Adult, Anti-HIV Agents administration & dosage, HIV Infections drug therapy, Infectious Disease Transmission, Vertical prevention & control, Lopinavir administration & dosage, Pregnancy Complications, Infectious drug therapy, Ritonavir administration & dosage
- Abstract
Objectives: To assess the influence of body weight and missed doses on lopinavir pharmacokinetics with standard and increased doses of lopinavir/ritonavir melt extrusion tablets during late pregnancy., Patients and Methods: Lopinavir concentration data during the third trimester of pregnancy were pooled from clinical trials in Thailand (NCT00409591) and the USA (NCT00042289). A total of 154 HIV-infected pregnant women receiving either 400/100 mg (standard) or 600/150 mg (increased) twice daily had lopinavir plasma concentration data available. Population parameters were estimated using non-linear mixed-effects regression models. Monte Carlo simulations were performed to estimate the probability of achieving target lopinavir trough concentrations (>1.0 mg/L) with standard and increased doses of lopinavir/ritonavir during pregnancy., Results: The median (range) age, weight and gestational age were 28 years (18-43), 62 kg (45-123) and 33 weeks (29-38), respectively. Body weight influenced lopinavir oral clearance (CL/F) and volume of distribution (V/F). Population estimates of lopinavir CL/F and V/F were 6.21 L/h/70 kg and 52.6 L/70 kg, respectively. Based on simulations, the highest risk of subtherapeutic trough concentrations was for women weighing >100 kg using the standard dose (∼ 7%), while the risk was <2% with the 600/150 mg dose for women weighing 40-130 kg. After a missed dose, 61% of women have lopinavir concentrations below target prior to the next dose with the standard dose compared with 42% with the increased dose., Conclusions: Standard dosing provides adequate lopinavir trough concentrations for the majority of pregnant women but increased doses may be preferable for women weighing >100 kg and with a history of lopinavir/ritonavir use and/or adherence issues., (© The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2015
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17. Plasma first in the field for postinjury hemorrhagic shock.
- Author
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Moore EE, Chin TL, Chapman MC, Gonzalez E, Moore HB, Silliman CC, Hansen KC, Sauaia A, and Banerjee A
- Subjects
- Blood Coagulation, Emergency Medical Services, Emergency Medicine methods, Hemorrhage prevention & control, Humans, Military Personnel, Treatment Outcome, United States, Wounds and Injuries therapy, Blood Component Transfusion methods, Plasma chemistry, Resuscitation methods, Shock, Hemorrhagic complications, Shock, Hemorrhagic therapy
- Abstract
Hemorrhage is the most preventable cause of death in civilian and military trauma, and despite tremendous advances in patient transport in the field, survival within the first hour has changed little over the past 40 years. The pathogenesis of trauma-induced coagulopathy is multifactorial, but most authorities believe there is an early depletion of clotting factors. While fresh frozen plasma delivered early in the emergency department has been shown to be beneficial, the rapid onset of trauma-induced coagulopathy suggests advancing this concept to the scene may improve patient outcome. The purpose of this report was to describe the rationale and design of a randomized trial to test the hypothesis that prehospital "plasma-first" resuscitation will benefit the critically injured patient. The rationale includes the possibility that plasma-first resuscitation may be advantageous beyond direct effects on clotting capacity. The study design is based on a ground ambulance system that allows rapid prehospital thawing of frozen plasma.
- Published
- 2014
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18. Specific protein content of pools of plasma for fractionation from different sources: impact of frequency of donations.
- Author
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Laub R, Baurin S, Timmerman D, Branckaert T, and Strengers P
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- Antibodies, Bacterial blood, Antibodies, Bacterial chemistry, Antibodies, Viral analysis, Antibodies, Viral blood, Blood Proteins analysis, Europe, Humans, Immunoglobulin G analysis, Immunoglobulin G blood, Parvovirus B19, Human, Plasma chemistry, Streptococcus pneumoniae, United States, Blood Donors, Blood Proteins metabolism, Plasma metabolism
- Abstract
Background and Objectives: Plasma pools for the production of human plasma medicinal products are distinguished according to the collection method (recovered or apheresis plasma) and the donor remuneration status. National regulations and the physical status of the donor determine the donation frequency and plasma volume per session. Relevant protein contents of different types of pools have not fully been compared., Materials and Methods: We compared the levels of total protein, 15 main relevant plasma protein markers, and anti-B19 and anti-Streptococcus pneumoniae IgG in single-type pools of donations from different countries (Belgium, Finland, France, the Netherlands, Germany, United States). Both recovered plasma from non-remunerated donors and apheresis plasma from remunerated and non-remunerated donors were studied., Results: Pools from paid US high-frequency, high-volume plasmapheresis donors showed significantly lower total protein (-9%), albumin (-15%), total IgG (-24%), IgM (-28%), hemopexin (-11%) and retinol-binding protein (-10%) but higher C1-inhibitor, pre-albumin and C-reactive protein contents than pools from unpaid European Union (EU) or US whole-blood or plasmapheresis donors. In contrast to pools from compensated EU plasmapheresis donors, pools from unpaid whole-blood or plasmapheresis donors showed no significant differences, whatever the collection method or country. Reductions in specific protein contents correlated well with protein half-life., Conclusion: These results should be taken into account with regard to donor health management and protein recovery., (© 2010 The Author(s). Vox Sanguinis © 2010 International Society of Blood Transfusion.)
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- 2010
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19. Accumulation of neutral lipids in peripheral blood mononuclear cells as a distinctive trait of Alzheimer patients and asymptomatic subjects at risk of disease.
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Pani A, Mandas A, Diaz G, Abete C, Cocco PL, Angius F, Brundu A, Muçaka N, Pais ME, Saba A, Barberini L, Zaru C, Palmas M, Putzu PF, Mocali A, Paoletti F, La Colla P, and Dessì S
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers, Cholesterol, HDL blood, Female, Humans, Intelligence Tests, Male, Middle Aged, Plasma chemistry, Severity of Illness Index, Statistics as Topic, United States, Young Adult, Alzheimer Disease pathology, Leukocytes, Mononuclear metabolism, Phospholipids metabolism
- Abstract
Background: Alzheimer's disease is the most common progressive neurodegenerative disease. In recent years, numerous progresses in the discovery of novel Alzheimer's disease molecular biomarkers in brain as well as in biological fluids have been made. Among them, those involving lipid metabolism are emerging as potential candidates. In particular, an accumulation of neutral lipids was recently found by us in skin fibroblasts from Alzheimer's disease patients. Therefore, with the aim to assess whether peripheral alterations in cholesterol homeostasis might be relevant in Alzheimer's disease development and progression, in the present study we analyzed lipid metabolism in plasma and peripheral blood mononuclear cells from Alzheimer's disease patients and from their first-degree relatives., Methods: Blood samples were obtained from 93 patients with probable Alzheimer's disease and from 91 of their first-degree relatives. As controls we utilized 57, cognitively normal, over-65 year-old volunteers and 113 blood donors aged 21-66 years, respectively. Data are reported as mean +/- standard error. Statistical calculations were performed using the statistical analysis software Origin 8.0 version. Data analysis was done using the Student t-test and the Pearson test., Results: Data reported here show high neutral lipid levels and increased ACAT-1 protein in about 85% of peripheral blood mononuclear cells freshly isolated (ex vivo) from patients with probable sporadic Alzheimer's disease compared to about 7% of cognitively normal age-matched controls. A significant reduction in high density lipoprotein-cholesterol levels in plasma from Alzheimer's disease blood samples was also observed. Additionally, correlation analyses reveal a negative correlation between high density lipoprotein-cholesterol and cognitive capacity, as determined by Mini Mental State Examination, as well as between high density lipoprotein-cholesterol and neutral lipid accumulation. We observed great variability in the neutral lipid-peripheral blood mononuclear cells data and in plasma lipid analysis of the subjects enrolled as Alzheimer's disease-first-degree relatives. However, about 30% of them tend to display a peripheral metabolic cholesterol pattern similar to that exhibited by Alzheimer's disease patients., Conclusion: We suggest that neutral lipid-peripheral blood mononuclear cells and plasma high density lipoprotein-cholesterol determinations might be of interest to outline a distinctive metabolic profile applying to both Alzheimer's disease patients and asymptomatic subjects at higher risk of disease.
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- 2009
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20. Severe eczema vaccinatum in a household contact of a smallpox vaccinee.
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Vora S, Damon I, Fulginiti V, Weber SG, Kahana M, Stein SL, Gerber SI, Garcia-Houchins S, Lederman E, Hruby D, Collins L, Scott D, Thompson K, Barson JV, Regnery R, Hughes C, Daum RS, Li Y, Zhao H, Smith S, Braden Z, Karem K, Olson V, Davidson W, Trindade G, Bolken T, Jordan R, Tien D, and Marcinak J
- Subjects
- Antibodies, Viral blood, Antibodies, Viral therapeutic use, Benzamides therapeutic use, Child, Preschool, Cidofovir, Cytosine analogs & derivatives, Cytosine therapeutic use, DNA, Viral blood, Dermatitis, Atopic complications, Family Health, Female, Humans, Immunoglobulin G blood, Immunoglobulin M blood, Immunoglobulins, Intravenous therapeutic use, Isoindoles therapeutic use, Kaposi Varicelliform Eruption pathology, Kaposi Varicelliform Eruption surgery, Male, Organophosphonates therapeutic use, Plasma chemistry, Skin Transplantation, United States, Kaposi Varicelliform Eruption drug therapy, Smallpox Vaccine
- Abstract
Background: We report the first confirmed case of eczema vaccinatum in the United States related to smallpox vaccination since routine vaccination was discontinued in 1972. A 28-month-old child with refractory atopic dermatitis developed eczema vaccinatum after exposure to his father, a member of the US military who had recently received smallpox vaccine. The father had a history of inactive eczema but reportedly reacted normally to the vaccine. The child's mother also developed contact vaccinia infection., Methods: Treatment of the child included vaccinia immune globulin administered intravenously, used for the first time in a pediatric patient; cidofovir, never previously used for human vaccinia infection; and ST-246, an investigational agent being studied for the treatment of orthopoxvirus infection. Serological response to vaccinia virus and viral DNA levels, correlated with clinical events, were utilized to monitor the course of disease and to guide therapy. Burn patient-type management was required, including skin grafts., Results: The child was discharged from the hospital after 48 days and has recovered with no apparent systemic sequelae or significant scarring., Conclusion: This case illustrates the need for careful screening prior to administration of smallpox vaccine and awareness by clinicians of the ongoing vaccination program and the potential risk for severe adverse events related to vaccinia virus.
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- 2008
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21. Reliability of plasma carotenoid biomarkers and its relation to study power.
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Al-Delaimy WK, Natarajan L, Sun X, Rock CL, and Pierce JP
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- Aged, Breast Neoplasms, Carotenoids administration & dosage, Cohort Studies, Epidemiologic Research Design, Female, Fruit, Humans, Middle Aged, Models, Statistical, Randomized Controlled Trials as Topic, Reproducibility of Results, Sensitivity and Specificity, United States, Vegetables, Biomarkers blood, Carotenoids blood, Plasma chemistry
- Abstract
Background: The reliability of biomarkers profoundly impacts validity of their use in epidemiology and can have serious implications for study power and the ability to find true associations. We assessed reliability of plasma carotenoid levels over time and how it could influence study power through sample size and effect-size., Methods: Plasma carotenoid levels were measured in a cohort study of 1323 women participating in the control arm of the Women's Healthy Eating and Living Study. We compared mean plasma levels at baseline, year 1, and year 4 of the study for alpha-carotene, beta-carotene, lycopene, lutein, and beta-cryptoxanthin. Reliability of these levels over time was assessed by Spearman correlations and intraclass correlation., Results: We found limited variation in mean levels between any 2 time points. Variation did not exceed 8% for lycopene, lutein, and beta-cryptoxanthin, 15% for alpha-carotene, and 18% for beta-carotene. Spearman correlations for individual carotenoids over time varied between 0.50 and 0.80, with lycopene having the lowest correlation. Intraclass correlations ranged from 0.47 to 0.66 for carotenoids., Conclusion: Intraclass correlations for plasma carotenoids over a period of several years are acceptable for epidemiologic studies. However, such variation is enough to decrease statistical power and increase the sample size needed to detect a given effect.
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- 2008
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22. Are quality differences responsible for different adverse reactions reported for SD-plasma from USA and Europe?
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Salge-Bartels U, Breitner-Ruddock S, Hunfeld A, Seitz R, and Heiden M
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- Blood Coagulation Factors analysis, Complement C3a analysis, Europe, Fibrin analysis, Humans, Lipoprotein(a) analysis, Plasma chemistry, Protein S analysis, Thromboembolism etiology, United States, Plasma Exchange adverse effects, Plasma Exchange standards
- Abstract
Thromboembolic adverse reactions reported after transfusion of SD-plasma in the United States (US) prompted us to perform a comparative study with SD-plasma from the US and the European (EU) market. In SD-plasma from US, residual tri-N-butyl phosphate was found, and citrate concentrations were lower than in EU-plasma. Except for substantial losses of FV, FVIII and antiplasmin found for all SD-plasmas, clotting factor activities were mainly retained. However, for SD-plasma from US, markedly elevated concentrations of lipoprotein (a) [Lp(a)], fibrin monomer and a particularly high degree of complement activation (C3a des-Arg) were observed. Furthermore, pronounced differences were found for protein S. Although SD-plasma pools from US contained nearly normal concentrations of free and bound protein S antigen, protein S activities were almost completely absent. In contrast to this, SD-plasma from EU showed a moderate loss of both protein S activity and free antigen. Antitrypsin inhibitor activities were much more diminished in SD-plasma from US than from EU. In view of a possible thrombogenicity of SD-plasma from US, the loss of protein S and elevated Lp(a) concentrations could be of significance. The very high levels of C3a des-Arg in US plasma could possibly have an additional effect, through priming platelet activation after transfusion.
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- 2006
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23. Analytic bias of thyroid function tests: analysis of a College of American Pathologists fresh frozen serum pool by 3900 clinical laboratories.
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Steele BW, Wang E, Klee GG, Thienpont LM, Soldin SJ, Sokoll LJ, Winter WE, Fuhrman SA, and Elin RJ
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- Calibration standards, Clinical Laboratory Techniques standards, Data Collection standards, Data Collection statistics & numerical data, Humans, Observer Variation, Thyrotropin blood, Thyroxine blood, Triiodothyronine blood, United States, Pathology, Clinical standards, Plasma chemistry, Thyroid Function Tests standards, Thyroid Function Tests statistics & numerical data
- Abstract
Context: In proficiency testing surveys, there are differences in the values reported by users of various analytic methods. Two contributors to this variation are calibrator bias and matrix effects of proficiency testing materials., Objectives: (1) To quantify the biases of the analytic methods used to measure thyroid-stimulating hormone, thyroxine, triiodothyronine, free thyroxine, and free triiodothyronine levels; (2) to determine if these biases are within allowable limits; and (3) to ascertain if proficiency testing materials correctly identify these biases., Design: A fresh frozen serum specimen was mailed as part of the 2003 College of American Pathologists Ligand and Chemistry surveys. The means and SDs for each analytic method were determined for this sample as well as for a proficiency testing sample from both surveys. In the fresh frozen serum sample, target values for thyroxine and triiodothyronine were determined by isotope dilution/liquid chromatography/tandem mass spectrometry. All other target values in the study were the median of the means obtained for the various analytic methods., Main Outcome Measures: Calibration biases were calculated by comparing the mean of each analytic method with the appropriate target values. These biases were evaluated against limits based on intra- and interindividual biological variation. Matrix effects of proficiency testing materials were assessed by comparing the rank of highest to lowest analytic method means (Spearman rank test) for each analyte., Participants: Approximately 3900 clinical laboratories were enrolled in the College of American Pathologists Chemistry and Ligand surveys., Results: The number of methods in the Ligand Survey that failed to meet the goals for bias was 7 of 17 for thyroid-stimulating hormone and 11 of 13 for free thyroxine. The failure rates were 12 of 16 methods for thyroxine, 8 of 11 for triiodothyronine, and 9 of 11 for free triiodothyronine. The means of the analytic method for the proficiency testing material correlated significantly (P < .05) only with the fresh frozen serum means for thyroxine and thyroid-stimulating hormone in the Chemistry Survey and free triiodothyronine in the Ligand Survey., Conclusions: A majority of the methods used in thyroid function testing have biases that limit their clinical utility. Traditional proficiency testing materials do not adequately reflect these biases.
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- 2005
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24. Comparison of fresh frozen serum to traditional proficiency testing material in a College of American Pathologists survey for ferritin, folate, and vitamin B12.
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Bock JL, Endres DB, Elin RJ, Wang E, Rosenzweig B, and Klee GG
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- Clinical Laboratory Techniques statistics & numerical data, Data Collection standards, Data Collection statistics & numerical data, Humans, Observer Variation, United States, Clinical Laboratory Techniques methods, Clinical Laboratory Techniques standards, Ferritins blood, Folic Acid blood, Pathology, Clinical standards, Plasma chemistry, Vitamin B 12 blood
- Abstract
Context: Comparison of different analytical methods in proficiency surveys may be affected by the artificial nature of the survey material., Objective: To compare intermethod differences in proficiency survey results between 2 types of survey material, conventional proficiency testing material (PTM) and fresh frozen human serum (FFS), for 3 markers of anemia: ferritin, folate, and vitamin B12., Design: Data were gathered from a 2003 survey event in the College of American Pathologists Ligand ("K") Series, in which the specimens to be tested by each participating laboratory included 1 vial of FFS and 2 vials of PTM with different analyte concentrations. The more than 1600 laboratories subscribing to the survey were not advised as to the nature of the specimens., Main Outcome Measures: The bias of each method relative to the median of method means for each analyte and each type of survey material, and the interlaboratory coefficient of variation for each method., Results: For each of the 3 analytes, moderate to large method biases were observed. For ferritin, method biases correlated strongly between comparable PTM and FFS specimens (Spearman r = 0.863, P < .001), whereas virtually no correlation was found for folate (r = -0.224, P = .48), and a marginally significant correlation existed for B12 (r = 0.55, P = .049)., Conclusions: With ferritin, proficiency survey performance of PTM is similar to that of FFS, implying that method biases relate mainly to calibration. With folate and to a lesser extent with B12, PTM and FFS exhibit different method biases, implying that the biases reflect analyte heterogeneity and/or matrix effects.
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- 2005
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25. Comparison of pooled fresh frozen serum to proficiency testing material in College of American Pathologists surveys: cortisol and immunoglobulin E.
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Palmer-Toy DE, Wang E, Winter WE, Soldin SJ, Klee GG, Howanitz JH, and Elin RJ
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- Clinical Laboratory Techniques standards, Data Collection methods, Data Collection statistics & numerical data, Humans, Observer Variation, Prospective Studies, Single-Blind Method, United States, Hydrocortisone blood, Immunoglobulin E blood, Pathology, Clinical standards, Plasma chemistry
- Abstract
Context: The College of American Pathologists (CAP) provides proficiency testing (PT) surveys to laboratories around the world., Objectives: To compare diagnostic assay methods for serum/plasma cortisol and immunoglobulin (Ig) E in terms of their bias and precision, to determine how well CAP PT specimens simulate human serum, and to reassess proficiency test grading criteria in light of these findings., Design: A participant-blinded, prospective trial. One vial of pooled fresh frozen serum (FFS) and 4 different admixtures of PT material (PTM) were sent to laboratories participating in PT surveys., Participants: Laboratories providing cortisol (>1000) or IgE (>230) results among the subscribers to the CAP surveys, Ligand (General) 2003, set K/KN-A and Chemistry 2003, set C-C., Main Outcome Measures: The main outcome measures were (1) bias among laboratories using the same method (peer groups), defined relative to the median of method means (MedMM); (2) imprecision as measured by the SD and coefficient of variation (CV) about each method mean; and (3) total error across laboratories for the FFS cortisol results, defined as |Bias Relative to Reference Method| + 2 SD., Results: Cortisol method biases, relative to MedMM, ranged from -22% to 9% for the FFS challenge and from -24% to 36% for comparable PTM challenges. The method biases, relative to the reference method, ranged from -3% to 19% for the FFS challenge. The cortisol method CVs ranged from 4.2% to 13.6% for the FFS challenge and from 4.7% to 12.7% for comparable PTM challenges. Total error across laboratories ranged from 1.4 to 6.9 microg/dL (39 to 190 nmol/L) for the FFS challenge. Immunoglobulin E method biases, relative to MedMM, ranged from -8% to 9% for the FFS challenge and from -7% to 5% for comparable PTM challenges. The IgE method CVs ranged from 3.6% to 6.7% for the FFS challenge and from 3.4% to 9.8% for comparable PTM challenges., Conclusions: The bias for cortisol results was less with FFS than with PTM, but imprecision was comparable. The FFS MedMM was 8.5% higher than the reference value. Fresh frozen serum and PTM bias and imprecision for IgE methods were each less than 10%. Because some of the methods demonstrated greater bias when analyzing PTM than FFS, peer group grading of both these analytes is appropriate.
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- 2005
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26. Creatinine measurement: state of the art in accuracy and interlaboratory harmonization.
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Miller WG, Myers GL, Ashwood ER, Killeen AA, Wang E, Thienpont LM, and Siekmann L
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- Bacteriological Techniques methods, Bacteriological Techniques statistics & numerical data, Clinical Laboratory Techniques instrumentation, Clinical Laboratory Techniques standards, Data Collection methods, Data Collection statistics & numerical data, Glomerular Filtration Rate, Humans, Observer Variation, Plasma chemistry, Plasma metabolism, Plasma microbiology, United States, Creatinine blood, Pathology, Clinical standards
- Abstract
Context: The National Kidney Disease Education Program recommends calculating glomerular filtration rate from serum creatinine concentration. Accurate creatinine measurements are necessary for this calculation., Objective: To evaluate the state of the art in measuring serum creatinine, as well as the ability of a proficiency testing program to measure bias for individual laboratories and method peer groups., Design: A fresh-frozen, off-the-clot pooled serum specimen plus 4 conventional specimens were sent to participants in the College of American Pathologists Chemistry Survey for assay of creatinine. Creatinine concentrations were assigned by isotope dilution mass spectrometry reference measurement procedures., Participants: Clinical laboratories with an acceptable result for all 5 survey specimens (n = 5624)., Results: The fresh frozen serum (FFS) specimen had a creatinine concentration of 0.902 mg/dL (79.7 micromol/L). Mean bias for 50 instrument-method peer groups varied from -0.06 to 0.31 mg/dL (-5.3 to 27.4 micromol/L), with 30 (60%) of 50 peer groups having significant bias (P < .001). The bias variability was related to instrument manufacturer (P < or = .001) rather than method type (P = .02) with 24 (63%) of 38 alkaline picric acid methods and with 6 (50%) of 12 enzymatic methods having significant biases. Two conventional specimens had creatinine concentrations of 0.795 and 2.205 mg/dL (70.3 and 194.9 micromol/L) and had apparent survey biases significantly different (P < .001) from that of the FFS specimen for 34 (68%) and 35 (70%) of 50 peer groups, respectively., Conclusions: Thirty of 50 peer groups had significant bias for creatinine. Bias was primarily associated with instrument manufacturer, not with type of method used. Proficiency testing using a commutable specimen measured participant bias versus a reference measurement procedure and provided trueness surveillance of instrument-method peer groups.
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- 2005
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27. Total long-term within-laboratory precision of cortisol, ferritin, thyroxine, free thyroxine, and thyroid-stimulating hormone assays based on a College of American Pathologists fresh frozen serum study: do available methods meet medical needs for precision?
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Steele BW, Wang E, Palmer-Toy DE, Killeen AA, Elin RJ, and Klee GG
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- Clinical Laboratory Techniques statistics & numerical data, Data Collection standards, Data Collection statistics & numerical data, Humans, Observer Variation, United States, Clinical Laboratory Techniques standards, Ferritins blood, Hydrocortisone blood, Pathology, Clinical standards, Plasma chemistry, Thyrotropin blood, Thyroxine blood, Time
- Abstract
Context: It is important that the total long-term precision of laboratory methods meet the medical needs of the patients being served., Objectives: To determine the long-term within- and between-laboratory variation of cortisol, ferritin, thyroxine, free thyroxine, and thyroid-stimulating hormone measurements using commonly available methods and to determine if these variations are within accepted medical needs., Design: Two vials of pooled frozen serum were mailed 6 months apart to laboratories participating in 2 separate College of American Pathologists surveys. The data from those laboratories that analyzed an analyte in both surveys were used to determine for each method the total variance and the within- and between-laboratory components., Setting: The study included the A mailing of the 2003 College of American Pathologists Ligand Survey and the C mailing of the Chemistry Survey., Main Outcome Measures: For each analyte, total variance was partitioned into within- and between-laboratory components for each analytic method. The within-laboratory variations were then compared with imprecision criteria based on biological variation., Participants: The laboratories that reported results on the same analyte using the same method in both surveys., Results: For each analyte, the median of the long-term within-laboratory variances of each peer group was 78% to 95% of its total-survey variance, and the median long-term within-laboratory coefficients of variation varied from 5.1% to 7.6%. The number of methods that met within-laboratory imprecision goals based on biological criteria were 5 of 5 for cortisol; 5 of 7 for ferritin; 0 of 7 for thyroxine and free thyroxine; and 8 of 8 for thyroid-stimulating hormone., Conclusions: For all analytes tested, the total within-laboratory component of variance was the major source of variability in this study. In addition, there are several methods, especially for thyroxine and free thyroxine, that may not meet analytic goals in terms of their imprecision.
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- 2005
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28. A comparison of human chorionic gonadotropin- related components in fresh frozen serum with the proficiency testing material used by the College of American Pathologists.
- Author
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Knight GJ, Palomaki GE, Klee GG, Schreiber WE, and Cole LA
- Subjects
- Clinical Laboratory Techniques statistics & numerical data, Data Collection standards, Data Collection statistics & numerical data, Humans, Observer Variation, United States, Chorionic Gonadotropin blood, Chorionic Gonadotropin, beta Subunit, Human blood, Clinical Laboratory Techniques methods, Clinical Laboratory Techniques standards, Pathology, Clinical standards, Plasma chemistry
- Abstract
Context: As part of a College of American Pathologists (CAP) proficiency testing survey, a comparison is made between human chorionic gonadotropin (hCG) results from an actual patient pool and a similarly targeted artificial sample. The goal is to gain insight into the possible source(s) of bias attributable to the proficiency testing material (PTM) with a view toward creating more appropriate survey materials., Objective: To compare hCG and related variants in a pool of fresh frozen sera (FFS) with that found in PTM., Design: The 2003 CAP K/KN-A Survey included a FFS specimen along with admixtures of PTM. The FFS (K-02) and 1 PTM admixture (K-01) had similar mean hCG values. Five hCG-related analytes were measured on these 2 samples by a reference laboratory., Participants: Approximately 1800 clinical laboratories and diagnostic test kit manufacturers participated in the K/ KN-A Survey., Main Outcome Measures: Method imprecision (coefficient of variation) and method bias (relative difference between peer group mean and all-method median) were computed for the 2 samples. Differences were evaluated with respect to hCG-related analytes levels., Results: All-method hCG results were 12.9 mIU/mL (12.9 IU/L) for the PTM material and 21.6 mIU/mL (21.6 IU/L) for the FFS material. Method biases for 14 manufacturers were greater for PTM than for FFS (-40% to +35% and -16% to +23%). Twelve of 14 methods had higher coefficients of variation on PTM. Total hCG and free beta hCG measurements by the reference laboratory were 14.1 mIU/ mL (14.1 IU/L) for the PTM material and 18.5 mIU/mL (18.5 U/L) for the FFS material (FFS), and 2.4 (PTM) and 0.7 (FFS) mIU/mL (2.4 and 0.7 IU/L), respectively. On a molar basis, free beta represented 17% and 4% of the total hCG, respectively. Levels of hyperglycosylated hCG, nicked hCG, and beta core fragment were not measurable in either sample., Conclusions: It is unlikely that the hCG added to the PTM is the source of the increased bias and variability. The main difference is a 3-fold increase in free beta found in the PTM, but methods previously found to strongly react with free beta were not systematically elevated. The biases between manufacturers found for the FFS specimen are likely attributable to calibration differences.
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- 2005
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29. Comparison of fresh frozen serum to proficiency testing material in College of American Pathologists surveys: alpha-fetoprotein, carcinoembryonic antigen, human chorionic gonadotropin, and prostate-specific antigen.
- Author
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Schreiber WE, Endres DB, McDowell GA, Palomaki GE, Elin RJ, Klee GG, and Wang E
- Subjects
- Clinical Laboratory Techniques statistics & numerical data, Data Collection standards, Data Collection statistics & numerical data, Humans, Immunoassay methods, Immunoassay standards, Immunoassay statistics & numerical data, Observer Variation, United States, Carcinoembryonic Antigen blood, Chorionic Gonadotropin blood, Clinical Laboratory Techniques methods, Clinical Laboratory Techniques standards, Pathology, Clinical standards, Plasma chemistry, Prostate-Specific Antigen blood, alpha-Fetoproteins metabolism
- Abstract
Context: Most proficiency testing materials (PTM) contain an artificial matrix that may cause immunoassays to perform differently with this material than with clinical samples. We hypothesized that matrix effects would be reduced by using fresh frozen serum (FFS)., Objective: To compare the performance of an FFS pool to standard PTM for measurement of alpha-fetoprotein, carcinoembryonic antigen, human chorionic gonadotropin (hCG), and prostate-specific antigen (PSA)., Design: One FFS specimen and 4 different admixtures of PTM were distributed in the 2003 College of American Pathologists K/KN-A (for alpha-fetoprotein, carcinoembryonic antigen, hCG, and total and free PSA) and C-C (hCG only) Surveys., Participants: The number of laboratories that participated in the surveys varied from a low of 288 (free PSA, K/KN-A Survey) to a high of 2659 (hCG, C-C Survey)., Main Outcome Measures: Method imprecision and method bias were compared between the FFS specimen and the standard PTM specimen with the closest value. Method imprecision was determined by calculating the coefficients of variation for each method and for all methods combined. Bias was defined as the proportional difference between peer-group mean and the median of all method means., Results: The FFS specimen gave significantly higher imprecision than PTM for the analytes alpha-fetoprotein, carcinoembryonic antigen, total PSA, and free PSA. For hCG, no substantial imprecision differences were observed in both surveys. Bias was significantly greater for the alpha-fetoprotein, carcinoembryonic antigen, and total PSA assays and significantly lower for the hCG and free PSA assays when comparing the FFS with the PTM., Conclusions: Fresh frozen serum did not provide consistently lower imprecision or bias than standard PTM in a survey of commonly ordered tumor markers.
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- 2005
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30. Viral safety evaluation of plasma-derived therapeutic products.
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Farshid M
- Subjects
- Animals, Humans, Plasma chemistry, Plasma virology, Safety, United States, Biological Products isolation & purification, Biological Products standards, Viruses isolation & purification
- Abstract
The viral safety of plasma-derived products, in the U.S., is ensured by a complementary approach consisting of donor screening for high-risk activities or history, donor testing for relevant blood-borne viruses, and the inclusion of viral clearance steps in the manufacturing process. Thus, any manufacturing process for the production of plasma-derived products should be validated for its capacity to clear viruses. This validation is performed by using small-scale laboratory models that mimic the actual manufacturing process with regard to its critical operating parameters and performance characteristics. In addition, there are a number of validation components that are deemed essential for obtaining reliable viral validation data. These include: (i) validation of the small-scale model to establish its relevance to the actual process; (ii) choice of viruses in performing spiking experiments; (iii) reliability and validity of the assays used to determine viral titer in the test articles and (iv) calculation of total log reductions in the validated steps.
- Published
- 2004
31. The impact of the intensity of serial automated plasmapheresis and the speed of deep-freezing on the quality of plasma.
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Hellstern P, Bach J, Haubelt H, Hitzler WE, Mathis S, and Vogt A
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- Blood Banks, Blood Coagulation Factors analysis, Blood Proteins analysis, Citric Acid analysis, Cryopreservation methods, Germany, Humans, Immunoglobulin G analysis, Plasma chemistry, Practice Guidelines as Topic, United States, Blood Preservation methods, Plasmapheresis instrumentation, Plasmapheresis methods
- Abstract
Background: Data are lacking on the impact that the intensity of serial donor plasmapheresis has on the quality of source plasma. A study was conducted to examine the quality of source plasma produced by intensive plasmapheresis and slow deep-freezing and to compare it to source plasma manufactured by moderate plasmapheresis and rapid freezing., Study Design and Methods: Seventy-five plasma samples from intensive plasmapheresis programs (Group 1) and 75 plasma units from moderate plasmapheresis programs (Group 2) were examined. The plasma had been deep-frozen either slowly at -30 degrees C in walk-in freezers (Group 1) or rapidly within 1 hour to a core temperature below -30 degrees C (Group 2). Determinations were made of the plasma levels of citrate; total protein; albumin; IgG; fibrinogen; factors II, V, VII, VIII, and IX; vWF; antithrombin; protein C; D-dimers; and prothrombin fragments 1+ 2., Results: Plasma units of Group 2 contained substantially greater levels of citrate, IgG, FVIII, and FV than samples of Group 1 (p<0.0001). Plasma levels of total protein, albumin, and fibrinogen also were higher in Group 2 (p<0.0001, p = 0.007, and p = 0.006, respectively). Neither plasmapheresis intensity nor freezing procedure had any influence on the levels of factors II, VII, and IX, antithrombin, or protein C. There was no evidence of substantial coagulation activation in the plasma units of either group. However, higher FVIII clotting activity/chromogenic substrate activity ratios in rapidly frozen plasmas and a significant correlation between these ratios and prothrombin fragment 1+ 2 levels suggest that rapid freezing yields both more native FVIII and greater partial activation of FVIII., Conclusion: Source plasma collected from donors undergoing intensified plasmapheresis contains markedly lower levels of IgG than plasma units produced by moderate serial plasmapheresis. The combination of intensified plasmapheresis and slower freezing of source plasma results in substantially lower levels of FV and FVIII than does moderate plasmapheresis with rapid freezing. Prospective studies should establish the optimum conditions required for the safe and economic production of source plasma for fractionation.
- Published
- 2001
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32. Diphtheria antitoxin levels in US blood and plasma donors.
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Gupta RK, Griffin P Jr, Xu J, Rivera R, Thompson C, and Siber GR
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- Animals, Chlorocebus aethiops, Diphtheria Toxoid blood, Enzyme-Linked Immunosorbent Assay methods, Humans, Immunoglobulin G blood, Neutralization Tests methods, Tetanus Toxoid, United States, Vero Cells, Blood Donors, Diphtheria Antitoxin blood, Plasma chemistry
- Abstract
Plasma samples from 500 blood donors were titrated for diphtheria antitoxin (DAT) by the toxin neutralization (TN) test. Only 1.6% of donors had <0.01 IU/mL DAT, the minimum protective level against diphtheria; 15% had levels between 0.01 and <0.1 IU/mL, indicating basic protection, and 83.4% had levels > or =0.1 IU, indicating full protection. Three hundred fifty samples were studied by ELISA for diphtheria toxoid IgG antibodies to assess the utility of the assay as a quick, convenient method for evaluating diphtheria immunity. Although the correlation between TN and ELISA titers for the 350 samples was high (r = .80), there was no correlation (r = .07) for samples with antitoxin titers <0.1 IU/mL, the level of special interest for serosurveys for protection. Titration of 62 immune globulin samples (prepared from 1957 to 1994) showed that DAT levels in Massachusetts blood donors increased concurrently with increased use of tetanus-diphtheria vaccine in the state.
- Published
- 1996
- Full Text
- View/download PDF
33. Electrifying research destroys pollutants that cause smog.
- Author
-
Belsie, Laurent
- Subjects
- *
PLASMA chemistry , *AIR pollution - Abstract
Discusses Los Alamos National Laboratory researcher Louis Rosocha's nonthermal plasma technology solution to handling pollutants that cause smog and air pollution. Use of the technology on volatile organic compounds (VOCs); Results of scientists' experiments with plasma technology on a contaminated site at McClellan Air Force Base in California; Advantages over incinerators.
- Published
- 1996
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