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PubMed1997

[Comparative validation of manual and automated methods for mixing and volume control of total blood samples].

During blood collection, agitation and volume limitations are critical to ensure thorough mixing of the blood with the anticoagulant and obtention of the predetermined volume. These 2 factors are essential to prevent blood activation and to obtain well standardized blood products. The objective of this study was to compare the quality of the blood collected using 2 types of collection method: tripping of a scale at a predetermined volume limit of 450 mL in the presence of manual agitation, and the 3 blood collection monitors currently available in France. A minimum of 100 collection procedures was performed for each of the 4 methods tested. Results were found to be equivalent using either the manual or the automated procedures with regard to both the accuracy and reproducibility of the blood volumes obtained and the collection times and flow rates. The characteristics of the red blood cell concentrates, platelet concentrates and plasma units prepared from the first 30 collections of each group were assessed and compared to regulatory requirements. The quality of all these products was found to be comparable to that currently observed at quality control and no product was rejected at the release control for reasons of poor collection. An assessment of the practicability of the different methods showed that the automated devices are subject to practical difficulties involving transport and battery loading. In addition, the cost of this equipment is approximately 5 times higher than that of the scales. In conclusion, the results of this study show that in our hands, no significant advantage could be expected from the use of automated blood collection monitors as compared to simple scales with manual mixing. These results further raise the question of the applicability to labile blood products of the comparative validations currently accepted in the pharmaceutical industry, in order to allow the use of correctly validated alternative methods.

Automation↗
PubMed1990

Evaluation of HLA-class II identity between unrelated individuals by serological typing, DNA-RFLP method, and mixed lymphocyte reaction.

Seven groups, each consisting of two to nine unrelated HLA-A, -B, and -DR serologically identical individuals, were analyzed by DNA-restriction fragment length polymorphism (RFLP) and mixed lymphocyte reactions (MLR) in order to evaluate HLA-class II identity between unrelated individuals and to assess the importance of HLA-class II incompatibilities detected by DNA-RFLP in the allogeneic reactions. It is clear that DNA-RFLP represents a powerful typing method for HLA-DR, -DQ, and -DP since the combinations of the RFLP band patterns define all the serological specificities and most of the cellular specificities to give a highly accurate typing. This report shows that an HLA-DP incompatibility induces proliferation in primary mixed lymphocyte culture (MLC) between unrelated HLA-A, -B, -DR, -DQ, and -DW identical individuals, which may suggest the importance of this molecule as a transplantation antigen, especially for unrelated bone marrow transplantations. Still, an isolated HLA-DPw4/HLA-DP a disparity did not induce any proliferation in MLC. Moreover, our results show that DQw7 (w3)/DQw8 (w3) disparity associated with HLA-DR4 represents a nonfunctional incompatibility in MLR. The HLA-Dw subtypes of HLA-DR specificities can induce a high proliferative response in MLC. The HLA-Dw subtypes of HLA-DR specificities can induce a high proliferative response in MLC. Finally, DNA-RFLP typing represents a reliable method for the selection of histocompatible donor-recipient pairs and could potentially reduce many logistic problems and delays in live-donor transplantation, especially for unrelated bone marrow transplantation.

Base Sequence↗
PubMed2005

A unified mixed-model method for association mapping that accounts for multiple levels of relatedness.

As population structure can result in spurious associations, it has constrained the use of association studies in human and plant genetics. Association mapping, however, holds great promise if true signals of functional association can be separated from the vast number of false signals generated by population structure. We have developed a unified mixed-model approach to account for multiple levels of relatedness simultaneously as detected by random genetic markers. We applied this new approach to two samples: a family-based sample of 14 human families, for quantitative gene expression dissection, and a sample of 277 diverse maize inbred lines with complex familial relationships and population structure, for quantitative trait dissection. Our method demonstrates improved control of both type I and type II error rates over other methods. As this new method crosses the boundary between family-based and structured association samples, it provides a powerful complement to currently available methods for association mapping.

Gene Expression↗
PubMed2006

A snore extraction method from mixed sound for a mobile snore recorder.

This paper presents a snore recorder that can separate snores from their delayed mixtures. This is useful to study the snore sounds of individuals when these sounds occur in a normal in-home sleeping environment, where two people are sleeping together and both produce sounds. Based on methods for blind source separation, we give a snore separator that solves the blind delayed source separation problem and provide a performance index to monitor its convergence. The separated snores can be analyzed to detect symptoms of sleep apnea prior to polysomnography or as a monitoring device after polysomnography has been performed. Experimental results show good performance of the snore separator.

Algorithms↗
PubMed2025

Systems Factors Contributing to Racial/Ethnic Disparities in Maternal Health: A Systematic Review.

INTRODUCTION: Despite ongoing efforts to reduce adverse maternal outcomes, including maternal mortality and severe maternal morbidity, racial/ethnic disparities in outcomes persist in high-income countries, including the United States (US) and Canada. Limited research has examined hospital-level factors that may drive disparities and contribute to adverse outcomes. This systematic review summarizes factors within the health system contributing to adverse outcomes and racial/ethnic disparities in the US and Canada to inform future policies and practices. METHOD: We searched SCOPUS, PubMed, EBSCOhost, and ProQuest Healthcare Administration for studies that reported hospital-level factors contributing to adverse maternal outcomes and racial/ethnic disparities. The review followed a two-stage screening process. The risk of bias of the included studies was evaluated using the Mixed Methods Appraisal Tool. The System Engineering Initiative for Patient Safety (SEIPS) 2.0 framework guided the identification and categorization of factors. RESULTS: Of 2441 studies retrieved, 30 met the inclusion criteria. Twenty-eight studies were conducted in the US, and 2 were conducted in Canada. The review included 16 qualitative, 11 quantitative, and 3 mixed-methods studies. We identified 60 factors associated with different system components, including person(s) (12%), tasks (28%), tools and technology (7%), internal environment (10%), organization (28%), and external environment (15%). Shortage of resources, including staffing, poor care coordination, and discriminatory organizational practices, were key factors described in the studies. CONCLUSION: Addressing health system factors in addition to broader societal factors is important to reduce adverse outcomes and promote equity for all women and birthing persons.

Humans↗
PubMed2026

Nursing students' perspective of dignity: A systematic review.

AIM: This review synthesizes research on nursing students' perceptions of dignity shaped by education and clinical experiences. BACKGROUND: Respect for human dignity is central to nursing ethics. While dignity is well studied in patient care, less focus has been given to how nursing students perceive and experience dignity during their education. DESIGN: A systematic review of quantitative, qualitative, and mixed-methods studies. METHODS: A comprehensive search was conducted across the Medline, PubMed, ScienceDirect, Scopus, and Web of Science databases for English-language studies published from 2000 to 2025. Quality was assessed using the Joanna Briggs Institute Critical Appraisal Checklist and the Mixed Methods Appraisal. Tool. Data were synthesized thematically. Reporting followed PRISMA guidelines. RESULTS: A total of 24 articles were included. Students viewed patient dignity as linked to respect, privacy, and autonomy. Although students had solid theoretical knowledge, they encountered institutional and professional barriers in delivering dignified care. Supportive environments and participation in decision-making enhanced their sense of dignity. Finally, educational strategies such as role-playing, simulations, and empathy exercises enhanced emotional and psychosocial awareness. CONCLUSIONS: These findings indicate that dignity is crucial in shaping nursing students' professional identity and ethical awareness throughout their education. Reinforcing ethical values and dignity in nursing education is essential for high-quality care.

Humans↗
PubMed1993

A modified method of mixed lymphocyte reaction: establishment of the assay system and its application to extracts of fungal cultures.

A modified mixed lymphocyte reaction (MLR) assay was developed to screen immunosuppressive agents. In the MLR, irradiation of splenocytes with UV light was employed for the preparation of stimulator cells, and the highest response was observed with the combination of splenocytes of C3H/He mice as a stimulator and those of C57BL/6 as a responder. The blastogenesis of the responder cells was quantified by a colorimetric method using MTT in 96-well microculture plates. For screening immunosuppressive substances, the MLR in combination with a cytotoxicity test can distinguish immunosuppressors from cytotoxic agents. The applications of this assay system to extracts of fungal culture was also described.

Animals↗
PubMed2004

Effect of drug-loading methods on drug load, encapsulation efficiency and release properties of alginate/poly-L-arginine/chitosan ternary complex microcapsules.

The drug-loaded alginate/poly-L-arginine/chitosan ternary complex microcapsules were prepared by mixing method, absorption method and the combined method of mixing and absorption, respectively. The effect of drug-loading methods on drug load, the encapsulation efficiency and the release properties of the complex microcapsules were investigated. The results showed that the absorption process is a dominating factor to greatly increase the drug load of Hb into microcapsules. Upon loading Hb into microcapsules by combined method of mixing and absorption, the drug load (19.9%) is up to the maximum value, and the encapsulation efficiency is 93.8%. Moreover, the drug release is a zero-order kinetics process for the ternary complex microcapsules made by mixing. For the complex microcapsules made by absorption, the drug release is a first-order kinetics. However, for the complex microcapsules made by combining the mixing and the absorption, the drug release obeys a first-order kinetics during the first eighteen hours, changing afterwards to a zero-order kinetics process. Effect of drug-loading methods on drug load and encapsulation efficiency of alginate/poly-L-arginine/chitosan ternary complex microcapsules.

Alginates↗
PubMed2005

Finite element modeling of coupled diffusion with partitioning in transdermal drug delivery.

The finite element method is employed to simulate two-dimensional (axisymmetric) drug diffusion from a finite drug reservoir into the skin. The numerical formulation is based on a general mathematical model for multicomponent nonlinear diffusion that takes into account the coupling effects between the different components. The presence of several diffusing components is crucial, as many transdermal drug delivery formulations contain one or more permeation enhancers in addition to the drug. The coupling between the drug and permeation enhancer(s) results in nonlinear diffusion with concentration-dependent diffusivities of the various components. The framework is suitable for modeling both linear and nonlinear, single- and multicomponent diffusions, however, as it reduces to the correct formulation simply by setting the relevant parameters to zero. In addition, we show that partitioning of the penetrants from the reservoir into the skin can be treated in a straightforward manner in this framework using the mixed method. Partitioning at interface boundaries poses some difficulty with the standard finite element method as it creates a discontinuity in the concentration variable at the interface. To our knowledge, nonlinear (concentration-dependent) partitioning in diffusion problems has not been treated numerically before, and we demonstrate that nonlinear partitioning may have an important role in the effect of permeation enhancers. The mixed method that we adopt includes the flux at the interface explicitly in the formulation, allowing the modeling of concentration-dependent partitioning of the permeants between the reservoir and the skin as well as constant (linear) partitioning. The result is a versatile finite element framework suitable for modeling both linear and nonlinear diffusions in heterogeneous media where the diffusivities and partition coefficients may vary in each subregion.

Administration, Cutaneous↗
PubMed2002

Comparison of methods to obtain a liquid phase in marine sediment toxicity bioassays with Paracentrotus lividus sea urchin embryos.

Sediment toxicity bioassays using planktonic organisms are widespread tools in environmental quality assessment, but they have limitations because the method for extracting and diluting the liquid phase may affect the final toxicity. The present study compares the toxicity on sea urchin embryos and larvae of elutriates and pore water obtained from intertidal sediments by various methods. The effects of mixing method, dilution protocol, aeration, and pH adjustment of the pore water are discussed. For a quantitative assessment of toxicity, a posteriori dilution of the elutriate yielded results comparable to mixing the equivalent proportions of sediment and sea water. The highest sensitivity was found by using pore water. Rotator mixing in air-tight closed flasks was a second-best choice. In both cases the geochemical parameters of the liquid phases obtained were not suitable for the incubation of water-column organisms. To avoid the environmentally irrelevant toxicity caused by these natural conditions typical of highly reduced sediments, gentle aeration or dilution with O2-saturated control sea water is necessary prior to testing, despite the unavoidable changes in redox conditions. Measuring length of 48-h-old larvae improves the sensitivity and the discriminating power of the test.

Animals↗
PubMed1998

A mixed culture recovery method indicates that enteric bacteria do not enter the viable but nonculturable state.

A new method, called the mixed culture recovery (MCR) method, has been developed to determine whether recovery of culturable bacterial cells from a population of largely nonculturable cells is due to resuscitation of the nonculturable cells from a viable but nonculturable state or simply to growth of residual culturable cells. The MCR method addresses this issue in that it involves the mixing of two easily distinguishable strains (e.g., lactose positive and negative) in such a way that large numbers of nonculturable cells of both strains are present together with a small number of culturable cells of only one strain, performing a nutrient addition resuscitation procedure, and then plating the cells to determine whether both cell types are recoverable. In repeated experiments with strains of Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis, Enterobacter aerogenes, and Salmonella choleraesuis, only cells of the culturable strain were recovered after application of various resuscitation techniques. These results suggest that the nonculturable cells were dead and that the apparent resuscitation was merely due to the growth of the remaining culturable cells.

Colony Count, Microbial↗
PubMed2006

Stakeholder-focused evaluation of an online course for health care providers.

INTRODUCTION: Different people who have a stake or interest in a training course (stakeholders) may have markedly different definitions of what constitutes "training success" and how they will use evaluation results. METHODS: Stakeholders at multiple levels within and outside of the organization guided the development of an evaluation plan for a Web-based training course on hemochromatosis. Stakeholder interests and values were reflected in the type, level, and rigor of evaluation methods selected. Our mixed-method evaluation design emphasized small sample sizes and repeated measures. RESULTS: Limited resources for evaluation were leveraged by focusing on the data needs of key stakeholders, understanding how they wanted to use evaluation results, and collecting data needed for stakeholder decision making. Regular feedback to key stakeholders provided opportunities for updating the course evaluation plan to meet emerging needs for new or different information. Early and repeated involvement of stakeholders in the evaluation process also helped build support for the final product. Involving patient advocacy groups, managers, and representative course participants improved the course and enhanced product dissemination. DISCUSSION: For training courses, evaluation planning is an opportunity to tailor methods and data collection to meet the information needs of particular stakeholders. Rigorous evaluation research of every training course may be infeasible or unwarranted; however, course evaluations can be improved by good planning. A stakeholder-focused approach can build a picture of the results and impact of training while fostering the practical use of evaluation data.

Centers for Disease Control and Prevention, U.S.↗
PubMed1989

Differences in the approaches of the doctor, manager, politician and social scientist in health care controversies--hospital case-mix management methods: an illustration of the manager's approach in health care controversies.

Resource allocation methods in health care are one of the major sources of controversies between managers, doctors, politicians and social scientists. In the past 10 years, an important innovation has appeared in hospital management and payment methods: case based systems, the most well known being the Diagnostic Related Group (DRG), that have been used for 5 years by Medicare in the U.S.A. to pay for hospital care. Through the analysis of the diffusion of DRGs in the U.S.A. and in France, we support the idea that DRGs are a typical illustration of the managerial approach to health care. They represent a significant breach in professional autonomy through the introduction of bureaucratic rationality. We also show how scientific controversies are structured by the dynamics of the diffusion of case based management systems.

Analysis of Variance↗