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1.
J Nutr ; 154(7): 2326-2334, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38580209

RESUMO

BACKGROUND: Anemia prevalence estimates reported in population surveys can vary based on the blood specimen source (capillary or venous) and analytic device (hematology autoanalyzers or portable hemoglobinometers) used for hemoglobin (Hb) determination. OBJECTIVES: This study aimed to compare accuracy and precision of Hb measurement in three blood specimen types on three models of hemoglobinometers against the results from venous blood from the same individuals measured on automated analyzers (AAs). METHODS: This multisite (Cambodia, Ethiopia, Guatemala, Lebanon, Nigeria, and Tanzania) study assessed Hb measurements in paired venous and capillary blood specimens from apparently healthy women (aged 15-49 y) and children (aged 12-59 mo) using three HemoCue® Hb models (201+, 301, and 801). Measurements were compared against reference values: venous blood in hematology AA and adjusted via regression calibration or mean difference in HemoCue® Hb. Venous, capillary pool, and single-drop capillary blood specimens were assessed for accuracy and precision. RESULTS: Venous blood measured using HemoCue® Hb 301 exhibited a positive mean error, whereas responses in HemoCue® Hb 201+ and 801 were nondirectional compared with the reference. Adjustment with the reference harmonized mean errors for all devices across study sites to <1.0 g/L using venous blood. Precision was highest for venous blood (±5-16 g/L) in all sites, lowest for single-drop capillary (±9-37 g/L), and intermediate (±9-28 g/L) for capillary pool blood specimen. Imprecision differed across sites, especially with both capillary blood specimens, suggesting different levels of personnel skills. CONCLUSIONS: Findings suggest that venous blood is needed for accurate and precise Hb determination. Single-drop capillary blood use should be discouraged owing to high measurement variability. Further research should evaluate the viability and reliability of capillary pool blood for this purpose. Accuracy of HemoCue® Hb devices can be improved via standardization against results from venous blood assessed using AA.


Assuntos
Capilares , Hemoglobinas , Humanos , Feminino , Adolescente , Hemoglobinas/análise , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Pré-Escolar , Reprodutibilidade dos Testes , Lactente , Hemoglobinometria/instrumentação , Hemoglobinometria/métodos , Hemoglobinometria/normas , Masculino , Veias , Anemia/sangue , Anemia/diagnóstico , Coleta de Amostras Sanguíneas/métodos , Criança
2.
Comput Toxicol ; 9: 61-72, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31008414

RESUMO

The fields of toxicology and chemical risk assessment seek to reduce, and eventually replace, the use of animals for the prediction of toxicity in humans. In this context, physiologically based kinetic (PBK) modelling based on in vitro and in silico kinetic data has the potential to a play significant role in reducing animal testing, by providing a methodology capable of incorporating in vitro human data to facilitate the development of in vitro to in vivo extrapolation of hazard information. In the present article, we discuss the challenges in: 1) applying PBK modelling to support regulatory decision making under the toxicology and risk-assessment paradigm shift towards animal replacement; 2) constructing PBK models without in vivo animal kinetic data, while relying solely on in vitro or in silico methods for model parameterization; and 3) assessing the validity and credibility of PBK models built largely using non-animal data. The strengths, uncertainties, and limitations of PBK models developed using in vitro or in silico data are discussed in an effort to establish a higher degree of confidence in the application of such models in a regulatory context. The article summarises the outcome of an expert workshop hosted by the European Commission Joint Research Centre (EC-JRC) - European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), on "Physiologically-Based Kinetic modelling in risk assessment - reaching a whole new level in regulatory decision-making" held in Ispra, Italy, in November 2016, along with results from an international survey conducted in 2017 and recently reported activities occurring within the PBK modelling field. The discussions presented herein highlight the potential applications of next generation (NG)-PBK modelling, based on new data streams.

3.
JBI Database System Rev Implement Rep ; 15(7): 1778-1782, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28708741

RESUMO

REVIEW QUESTION/OBJECTIVE: The objective of this review is to identify and synthesize the best available evidence on the effect of mobile health (mHealth) interventions in antenatal care utilization and skilled birth attendance in low- and middle-income countries.More specifically, the review questions are as follows.


Assuntos
Tocologia/normas , Cuidado Pré-Natal/estatística & dados numéricos , Telemedicina/métodos , Feminino , Necessidades e Demandas de Serviços de Saúde/normas , Humanos , Serviços de Saúde Materna/tendências , Tocologia/tendências , Avaliação de Resultados em Cuidados de Saúde , Gravidez , Revisões Sistemáticas como Assunto
4.
ACS Appl Mater Interfaces ; 7(1): 94-100, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25475257

RESUMO

For inorganic thermoelectric materials, Seebeck coefficient and electrical conductivity are interdependent, and hence optimization of thermoelectric performance is challenging. In this work we show that thermoelectric performance of PEDOT:PSS can be enhanced by greatly improving its electrical conductivity in contrast to inorganic thermoelectric materials. Free-standing flexible and smooth PEDOT:PSS bulky papers were prepared using vacuum-assisted filtration. The electrical conductivity was enhanced to 640, 800, 1300, and 1900 S cm(-1) by treating PEDOT:PSS with ethylene glycol, polyethylene glycol, methanol, and formic acid, respectively. The Seebeck coefficient did not show significant variation with the tremendous conductivity enhancement being 21.4 and 20.6 µV K(-1) for ethylene glycol- and formic acid-treated papers, respectively. This is because secondary dopants, which increase electrical conductivity, do not change oxidation level of PEDOT. A maximum power factor of 80.6 µW m(-1) K(-2) was shown for formic acid-treated samples, while it was only 29.3 µW m(-1) K(-2) for ethylene glycol treatment. Coupled with intrinsically low thermal conductivity of PEDOT:PSS, ZT ≈ 0.32 was measured at room temperature using Harman method. We investigated the reasons behind the greatly enhanced thermoelectric performance.

5.
ACS Appl Mater Interfaces ; 6(4): 2292-9, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-24460075

RESUMO

We proposed a facile film treatment with formic acid to enhance the conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) by 4 orders of magnitude. The effect of formic acid concentration on conductivity was investigated; conductivity increased fast with increasing concentration up to 10 M and then increased slightly, the highest conductivity being 2050 S cm(-1) using 26 M concentration. Formic acid treated PEDOT:PSS films also exhibited very high transmittances. The mechanism of conductivity enhancement was explored through SEM, AFM, and XPS. Formic acid with its high dielectric constant screens the charge between PEDOT and PSS bringing about phase separation between them. Increased carrier concentration, removal of PSS from the film, morphology, and conformation change with elongated and better connected PEDOT chains are the main mechanisms of conductivity enhancement. ITO-free polymer solar cells were also fabricated using PEDOT:PSS electrodes treated with different concentrations of formic acid and showed equal performance to that of ITO electrodes. The concentrated acid treatment did not impair the desirable film properties as well as stability and performance of the solar cells.

6.
Clin Exp Pharmacol Physiol ; 40(3): 190-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23278368

RESUMO

The aim of the present study was to investigate the natural killer (NK) cell phenotype and function in chronic hepatitis B virus (HBV) patients and to study the effects of entecavir therapy (10 mg/day, p.o.) on these responses. Peripheral blood NK cells were collected from 18 chronic HBV patients and 14 healthy controls. The effect of entecavir therapy on the phenotype and function of NK cells in chronic HBV patients was characterized by flow cytometry analysis. Concentrations of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), HBV viral loads in both groups and potential associations between the frequency of peripheral NK cell subsets and clinical measures were determined. There was a significant reduction in the number of CD3(-)CD56(+) NK cells in chronic HBV patients compared with healthy controls. Furthermore, there were significant increases in the percentage of CD3(-)CD56(+)NKG2D(+) and CD3(-)CD56(+)NKP30(+) NK activating receptors in chronic HBV patients compared with healthy individuals, who exhibited downregulated expression following entecavir treatment. Spearman's correlation analysis revealed that there was a significant positive correlation between the percentage of NKG2D(+) and NKP30(+) NK cells and serum ALT levels. Characterization of NK cell degranulation indicated that the frequency of CD107a(+) NK cells in HBV patients (in response to K562 stimulation) was significantly greater than in healthy controls but decreased following entecavir treatment. Entecavir treatment of hepatitis B e antigen-positive chronic HBV-infected patients not only led to a reduction in HBV DNA loads and normalization of ALT and AST levels, but also resulted in the recovery of NK cell-mediated immunity.


Assuntos
Antivirais/uso terapêutico , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Imunidade Celular/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Receptores de Células Matadoras Naturais/biossíntese , Adulto , Antivirais/administração & dosagem , Complexo CD3/biossíntese , Antígeno CD56/biossíntese , Regulação para Baixo , Feminino , Citometria de Fluxo , Guanina/administração & dosagem , Guanina/uso terapêutico , Anticorpos Anti-Hepatite B/sangue , Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Subfamília K de Receptores Semelhantes a Lectina de Células NK/biossíntese , Receptor 3 Desencadeador da Citotoxicidade Natural/biossíntese , Resultado do Tratamento , Carga Viral , Adulto Jovem
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