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2.
J Med Internet Res ; 22(10): e21955, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32924962

RESUMO

BACKGROUND: The Great COVID-19 Shutdown aimed to eliminate or slow the spread of SARS-CoV-2, the virus that causes COVID-19. The United States has no national policy, leaving states to independently implement public health guidelines that are predicated on a sustained decline in COVID-19 cases. Operationalization of "sustained decline" varies by state and county. Existing models of COVID-19 transmission rely on parameters such as case estimates or R0 and are dependent on intensive data collection efforts. Static statistical models do not capture all of the relevant dynamics required to measure sustained declines. Moreover, existing COVID-19 models use data that are subject to significant measurement error and contamination. OBJECTIVE: This study will generate novel metrics of speed, acceleration, jerk, and 7-day lag in the speed of COVID-19 transmission using state government tallies of SARS-CoV-2 infections, including state-level dynamics of SARS-CoV-2 infections. This study provides the prototype for a global surveillance system to inform public health practice, including novel standardized metrics of COVID-19 transmission, for use in combination with traditional surveillance tools. METHODS: Dynamic panel data models were estimated with the Arellano-Bond estimator using the generalized method of moments. This statistical technique allows for the control of a variety of deficiencies in the existing data. Tests of the validity of the model and statistical techniques were applied. RESULTS: The statistical approach was validated based on the regression results, which determined recent changes in the pattern of infection. During the weeks of August 17-23 and August 24-30, 2020, there were substantial regional differences in the evolution of the US pandemic. Census regions 1 and 2 were relatively quiet with a small but significant persistence effect that remained relatively unchanged from the prior 2 weeks. Census region 3 was sensitive to the number of tests administered, with a high constant rate of cases. A weekly special analysis showed that these results were driven by states with a high number of positive test reports from universities. Census region 4 had a high constant number of cases and a significantly increased persistence effect during the week of August 24-30. This change represents an increase in the transmission model R value for that week and is consistent with a re-emergence of the pandemic. CONCLUSIONS: Reopening the United States comes with three certainties: (1) the "social" end of the pandemic and reopening are going to occur before the "medical" end even while the pandemic is growing. We need improved standardized surveillance techniques to inform leaders when it is safe to open sections of the country; (2) varying public health policies and guidelines unnecessarily result in varying degrees of transmission and outbreaks; and (3) even those states most successful in containing the pandemic continue to see a small but constant stream of new cases daily.


Assuntos
Controle de Doenças Transmissíveis/legislação & jurisprudência , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Política de Saúde , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Informática em Saúde Pública/métodos , Betacoronavirus , Controle de Doenças Transmissíveis/métodos , Humanos , Modelos Estatísticos , Pandemias , Saúde Pública , Padrões de Referência , Análise de Regressão , Estados Unidos
3.
Lima; Perú. Ministerio de Salud; 20200800. 184 p. ilus, tab.
Monografia em Espanhol | LILACS, MINSAPERU | ID: biblio-1117777

RESUMO

El documento Política Nacional Multisectorial de Salud al 2030, contiene los antecedentes, la base legal en la cual se sustenta, la metodología seguida, diagnóstico, los objetivos, provisión de servicios y estándares, para culminar en el seguimiento y la evaluación.


Assuntos
Peru , Política , Padrões de Referência , Saúde , Diagnóstico , Política de Inovação e Desenvolvimento , Metodologia
4.
Nucl Med Commun ; 41(9): 965-976, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32796486

RESUMO

OBJECTIVES: The aim of this study was to characterize national variation in radionuclide calibrator activity response to a single National Institute of Standards and Technology (NIST) traceable reference Ge source used as a surrogate for F at clinical PET centres in England using National Physical Laboratory approved techniques. METHODS: Readings from 20 instruments at 13 centres using local F and Ge factor settings were recorded with the source located in vial and syringe positions. Ten repeat measurements were conducted to investigate repeatability using % coefficient of variability (COV). Comparison ratios to investigate accuracy were made between calibrator responses and decay-corrected NISTref reference activity for syringe and vial position measurements. RESULTS: The maximum %COV was 0.79%, while 90, 95 and 80% of calibrators conformed to 5% accuracy for F syringe, Ge syringe and Ge vial position readings, respectively. We revealed a trend towards reduced bias in measurements using Veenstra devices for F and using Capintec devices for Ge factor settings. CONCLUSIONS: This study demonstrated good repeatability in local device measurements. In total, 70% of English calibrators tested and 88% of all measurements performed achieved 5% accuracy. While statistically significant bias was exhibited between different vendor equipment dependent upon radioisotope selected, our study recommends regular traceability checks for optimum instrument performance conducted within National Metrology Institutes guidelines.


Assuntos
Germânio , Tomografia por Emissão de Pósitrons/normas , Radioisótopos , Compostos Radiofarmacêuticos/análise , Algoritmos , Calibragem , Inglaterra , Radioisótopos de Flúor/análise , Humanos , Imagens de Fantasmas , Padrões de Referência , Reprodutibilidade dos Testes , Seringas
5.
PLoS One ; 15(8): e0238064, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841285

RESUMO

BACKGROUND: Inappropriate prescribing in the elderly is a critical issue in primary care, causing a higher risk of Adverse Drug Reactions (ADRs) and resulting in major patient safety concerns. At international level, many tools have been developed to identify Potentially Inappropriate Medications (PIMs). OBJECTIVE: The aim of this study was the application of Beers, Screening Tool of Older People's Prescriptions (STOPP)/Screening Tool to Alert to Right Treatment (START) and Improving Prescribing in the Elderly Tool (IPET) criteria as key tool to improve the quality of prescribing. METHODS: A retrospective study was conducted using the aforementioned criteria. Two different cohorts of elderly patients were enrolled between January 2015 and December 2016, 1800 at admission and 1466 at hospital stay. The index of each criterion divided by politherapy were correlated with comorbidities (Pearson correlation). A comparison was made between admission and hospital stay through a Student's t test of the average of the index. RESULTS: The Proton Pump Inhibitors (PPIs) were the most prescribed PIMs according Beers criteria in both patient cohorts (56%). The most detected drug-drug and drug-disease interactions at admission and at hospital stay were 3 or more drugs active on the Central Nervous System (CNS) as they can predispose to fall-risk. The most detected PIMs with STOPP criteria at admission were PPIs administered for more than 8 weeks. Inhaled ß2-agonists or antimuscarinics were the most prescribed Potential Prescription Omissions (PPOs) according to START criteria. Nonsteroidal Anti-inflammatory Drugs (NSAIDs) in patients with high blood pressure were the most detected PIMs according to IPET criteria during hospital stay. A significant correlation between the comorbidities and the all index at hospital stay, while at admission there was no significant correlation for Beers and IPET index. CONCLUSION: The prescriptive criteria were a useful tool for assessing the quality of prescriptions in the geriatric population and identifying their critical issues.


Assuntos
Prescrições de Medicamentos/normas , Medicina Baseada em Evidências , Geriatria , Admissão do Paciente/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Prescrição Inadequada/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Padrões de Referência
6.
PLoS Genet ; 16(8): e1008927, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797036

RESUMO

The genetic control of gene expression is a core component of human physiology. For the past several years, transcriptome-wide association studies have leveraged large datasets of linked genotype and RNA sequencing information to create a powerful gene-based test of association that has been used in dozens of studies. While numerous discoveries have been made, the populations in the training data are overwhelmingly of European descent, and little is known about the generalizability of these models to other populations. Here, we test for cross-population generalizability of gene expression prediction models using a dataset of African American individuals with RNA-Seq data in whole blood. We find that the default models trained in large datasets such as GTEx and DGN fare poorly in African Americans, with a notable reduction in prediction accuracy when compared to European Americans. We replicate these limitations in cross-population generalizability using the five populations in the GEUVADIS dataset. Via realistic simulations of both populations and gene expression, we show that accurate cross-population generalizability of transcriptome prediction only arises when eQTL architecture is substantially shared across populations. In contrast, models with non-identical eQTLs showed patterns similar to real-world data. Therefore, generating RNA-Seq data in diverse populations is a critical step towards multi-ethnic utility of gene expression prediction.


Assuntos
Afro-Americanos/genética , Estudo de Associação Genômica Ampla/métodos , Modelos Genéticos , Transcriptoma , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Estudo de Associação Genômica Ampla/normas , Humanos , Locos de Características Quantitativas , RNA-Seq/métodos , RNA-Seq/normas , Padrões de Referência
7.
Nat Protoc ; 15(9): 2788-2812, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32770154

RESUMO

Flow cytometry has recently established itself as a tool to track short-term dynamics in microbial community assembly and link those dynamics with ecological parameters. However, instrumental configurations of commercial cytometers and variability introduced through differential handling of the cells and instruments frequently cause data set variability at the single-cell level. This is especially pronounced with microorganisms, which are in the lower range of optical resolution. Although alignment beads are valuable to generally minimize instrumental noise and align overall machine settings, an artificial microbial cytometric mock community (mCMC) is mandatory for validating lab workflows and enabling comparison of data between experiments, thus representing a necessary reference standard for the reproducible cytometric characterization of microbial communities, especially in long-term studies. In this study, the mock community consisted of two Gram-positive and two Gram-negative bacterial strains, which can be assembled with respective subsets of cells, including spores, in any selected ratio or concentration. The preparation of the four strains takes a maximum of 5 d, and the stains are storable with either PFA/ethanol fixation at -20 °C or drying at 4 °C for at least 6 months. Starting from this stock, an mCMC can be assembled within 1 h. Fluorescence staining methods are presented and representatively applied with two high-resolution cell sorters and three benchtop flow cytometers. Benchmarked data sets allow the use of bioinformatic evaluation procedures to decode community behavior or convey qualified cell sorting decisions for subsequent high-resolution sequencing or proteomic routines.


Assuntos
Bactérias/citologia , Técnicas Citológicas/normas , Microbiota , Biologia Computacional , Padrões de Referência , Reprodutibilidade dos Testes
8.
J Chromatogr A ; 1627: 461387, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823095

RESUMO

A simple and efficient magnetic solid-phase extraction (MSPE) method was established with magnetic covalent organic framework (COF) as adsorbent to enrich organophosphorus pesticides from fatty milk samples, followed by the sensitive determination via LC-MS/MS. The key parameters influencing the MSPE efficiency were comprehensively investigated to afford an optimized procedure. All the target analytes could be captured directly by magnetic COF from milk without protein precipitation, making the pretreatment rapid and convenient. Systematic method validation demonstrated its satisfactory linearity, recoveries (80.0-105 %), and precision (RSDs <12.3 %). The method limits of quantification were 0.2-0.5 µg L-1. A comparison experiment to the reported solid-phase extraction fully verified the present MSPE more rapid, accurate, and environment-friendly. Furthermore, FT-IR and XPS analysis were performed to reveal the adsorption mechanisms of magnetic COF to organophosphorus pesticides, which could offer guidance on the rational design of COF adsorbent for various target analytes.


Assuntos
Fenômenos Magnéticos , Estruturas Metalorgânicas/química , Leite/química , Compostos Organofosforados/análise , Praguicidas/análise , Extração em Fase Sólida/métodos , Acetonitrilos/análise , Adsorção , Animais , Limite de Detecção , Espectroscopia Fotoeletrônica , Padrões de Referência , Reprodutibilidade dos Testes , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier
9.
PLoS One ; 15(8): e0236898, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785280

RESUMO

The development of fungal fruiting bodies from a hyphal thallus is inducible under low temperature (cold stress). The molecular mechanism has been subject to surprisingly few studies. Analysis of gene expression level has become an important means to study gene function and its regulation mechanism. But identification of reference genes (RGs) stability under cold stress have not been reported in famous medicinal mushroom-forming fungi Cordyceps militaris. Herein, 12 candidate RGs had been systematically validated under cold stress in C. militaris. Three different algorithms, geNorm, NormFinder and BestKeeper were applied to evaluate the expression stability of the RGs. Our results showed that UBC and UBQ were the most stable RGs for cold treatments in short and long periods, respectively. 2 RGs (UBC and PP2A) and 3 RGs (UBQ, TUB and CYP) were the suitable RGs for cold treatments in short and long periods, respectively. Moreover, target genes, two-component-system histidine kinase genes, were selected to validate the most and least stable RGs under cold treatment, which indicated that use of unstable expressed genes as RGs leads to biased results. Our results provide a good starting point for accurate reverse transcriptase quantitative polymerase chain reaction normalization by using UBC and UBQ in C. militaris under cold stress and better support for understanding the mechanism of response to cold stress and fruiting body formation in C. militaris and other mushroom-forming fungi in future research.


Assuntos
Resposta ao Choque Frio/genética , Cordyceps/genética , Cordyceps/fisiologia , Perfilação da Expressão Gênica/normas , Histidina Quinase/genética , Cordyceps/enzimologia , Padrões de Referência
10.
J Chromatogr A ; 1626: 461328, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797818

RESUMO

Ferric oxide/carbon (Fe2O3@C) was fabricated via direct carbonization of metal-organic framework of iron (MOF-235) under argon atmosphere. The magnetic Fe2O3 nanoparticles are evenly embedded in porous carbon matrix, while original morphology of MOF-235 was well-maintained. The synthesized Fe2O3@C was used as magnetic sorbent for extracting five benzoylurea insecticides (BUs). The materials exhibited excellent extraction performance, which benefited not only from the strong π-π interaction and hydrophobic interaction (π-conjugated system), but also to the abundant adsorption sites and flexible transport channel (the interconnected 3D porous structure). A three-factor-three-level Box-Behnken design (BBD) was selected to optimize three greatly influential parameters: amount of adsorbent (A), desorption time (B) and volume of desorption solvent (C) by response surface methodology. The established method coupled to HPLC-UV detection showed wide linearity with the range of 0.2-450 µg•L-1, relatively low limits of detection (0.05-0.10 µg•L-1) with the relative standard deviation (RSD) (n = 7) lower t than 5.47%. Moreover, the proposed method was successfully applied to analyze BUs in tea samples and investigate the removal effect of different washing on BUs residues from tea leaf. These results indicated that the synthesized Fe2O3@C is a promising adsorbent material for magnetic solid phase extraction of BUs at trace concentrations from tea samples.


Assuntos
Inseticidas/análise , Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Chá/química , Ureia/análise , Adsorção , Carbono/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/normas , Compostos Férricos/química , Inseticidas/isolamento & purificação , Inseticidas/normas , Limite de Detecção , Porosidade , Padrões de Referência , Extração em Fase Sólida , Espectrofotometria Ultravioleta , Chá/metabolismo , Ureia/análogos & derivados , Ureia/isolamento & purificação , Ureia/normas
11.
J Chromatogr A ; 1626: 461333, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797819

RESUMO

The ultra-trace determination of nicotine and its 4 major metabolites (cotinine, nornicotine, norcotinine and anabasine) from rabbit plasma was achieved by a newly developed solid phase microextraction-liquid chromatography-tandem mass spectrometry method. Extraction of the target analytes was performed with hydrophilic/lipophilic balance-polyacrylonitrile SPME fibers. Dual fiber extraction was necessary to guarantee improved recovery at parts-per-trillion levels. Liquid chromatographic analysis was achieved in a 6-min run using a C18 (1.9 µm C18, 50 mm x 2.1 mm) column with a mobile phase flow rate of 0.4 mL/min. Tandem mass spectrometry was used for detection and quantification in positive electrospray ionization (ESI+) mode for all the targeted analytes. Two stable isotope-labeled internal standards were used for signal correction and accurate quantification. The mass spectrometer with laminar flow ion flux transport, guaranteed improved signal stability, minimal contamination of the ion guide and reproducibility into the first quadrupole analyzer. The method was validated in line with the Food and Drug Administration (FDA) guidelines for bioanalytical method validation. The results met the acceptance criteria as proposed by the FDA: accuracy was tested at 0.35, 10 and 75 µg L - 1 and ranged between 98.3-112.2% for nicotine, 94.1-101.9% for cotinine, 94.7-107.0% for nornicotine, 81.1-107.2% for norcotinine and 94.3-115.2% for anabasine, with precision up to 14.2%. Stability tests indicated that all the targeted analytes were stable in the desorption solution for at least 1 week. LOQs ranged from 0.05 to 1 µg L-1. The method was successfully applied to analyze plasma samples obtained from rabbits following transdermal application of a smoking cessation formulation loaded with solid lipid nanoparticles containing a nicotine-stearic acid conjugate.


Assuntos
Nicotina/sangue , Anabasina/sangue , Anabasina/isolamento & purificação , Anabasina/normas , Animais , Cromatografia Líquida de Alta Pressão/normas , Cotinina/análogos & derivados , Cotinina/sangue , Cotinina/isolamento & purificação , Cotinina/normas , Marcação por Isótopo , Limite de Detecção , Nicotina/análogos & derivados , Nicotina/isolamento & purificação , Nicotina/metabolismo , Nicotina/normas , Coelhos , Padrões de Referência , Reprodutibilidade dos Testes , Abandono do Hábito de Fumar , Microextração em Fase Sólida , Espectrometria de Massas em Tandem/normas , Fatores de Tempo
12.
Nat Commun ; 11(1): 3966, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769990

RESUMO

Prompt identification of acute coronary syndrome is a challenge in clinical practice. The 12-lead electrocardiogram (ECG) is readily available during initial patient evaluation, but current rule-based interpretation approaches lack sufficient accuracy. Here we report machine learning-based methods for the prediction of underlying acute myocardial ischemia in patients with chest pain. Using 554 temporal-spatial features of the 12-lead ECG, we train and test multiple classifiers on two independent prospective patient cohorts (n = 1244). While maintaining higher negative predictive value, our final fusion model achieves 52% gain in sensitivity compared to commercial interpretation software and 37% gain in sensitivity compared to experienced clinicians. Such an ultra-early, ECG-based clinical decision support tool, when combined with the judgment of trained emergency personnel, would help to improve clinical outcomes and reduce unnecessary costs in patients with chest pain.


Assuntos
Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/diagnóstico , Eletrocardiografia , Hospitais , Aprendizado de Máquina , Algoritmos , Bases de Dados como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Padrões de Referência
13.
Biologicals ; 67: 69-74, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: covidwho-712934

RESUMO

This second International Alliance for Biological Standardization COVID-19 webinar brought together a broad range of international stakeholders, including academia, regulators, funders and industry, with a considerable participation from low- and middle-income countries, to discuss the use of controlled human infection models to accelerate development and market authorization assessment of a vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Desenvolvimento de Medicamentos/ética , Experimentação Humana/ética , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/uso terapêutico , Desenvolvimento de Medicamentos/legislação & jurisprudência , Experimentação Humana/legislação & jurisprudência , Humanos , Controle de Qualidade , Padrões de Referência
14.
Biologicals ; 67: 69-74, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32829985

RESUMO

This second International Alliance for Biological Standardization COVID-19 webinar brought together a broad range of international stakeholders, including academia, regulators, funders and industry, with a considerable participation from low- and middle-income countries, to discuss the use of controlled human infection models to accelerate development and market authorization assessment of a vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Desenvolvimento de Medicamentos/ética , Experimentação Humana/ética , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/uso terapêutico , Desenvolvimento de Medicamentos/legislação & jurisprudência , Experimentação Humana/legislação & jurisprudência , Humanos , Controle de Qualidade , Padrões de Referência
15.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(4): 338-342, 2020 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-32762210

RESUMO

According to users and places, blood glucose monitoring systems(BGMSs) can be divided into self-monitoring blood glucose test systems(SMBGs) and Point-of-Care Blood Glucose monitoring systems(POC-BGMSs). The Food and Drug Administration(FDA) believes that standards for SMBGs and POC-BGMSs should be different because of different operators, different use environments, different intendance uses and different applicable populations. Now the international standards for evaluating BGMSs include ISO 15197:2013 issued by International Organization for Standardization(ISO), two guidelines on blood glucose monitoring systems issued by FDA, and POCT12-A3 guidelines issued by the American Association for Clinical and Laboratory Standardization(CLSI), ISO standard and FDA guideline-OTC are applicable in SMBGs, CLSI guideline and FDA guideline-POCTI2-A3 are suitable for POC-BGMSs. By analyzing the accuracy evaluation processes of BGMSs based on four standard documents, it is found that the accuracy evaluation of medical BGMSs is more stringent. It is proposed that SMBGs and POC-BGMSs should be supervised separately.


Assuntos
Automonitorização da Glicemia , Glicemia , Sistemas Automatizados de Assistência Junto ao Leito , Padrões de Referência , Reprodutibilidade dos Testes , Estados Unidos , United States Food and Drug Administration
16.
PLoS One ; 15(8): e0236338, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785215

RESUMO

Dysregulation of BCL2 is a pathophysiology observed in haematological malignancies. For implementation of available treatment-options it is preferred to know the relative quantification of BCL2 mRNA with appropriate reference genes. For the choice of reference genes-(i) Reference Genes were selected by assessing variation of >60,000 genes from 4 RNA-seq datasets of haematological malignancies followed by filtering based on their GO biological process annotations and proximity of their chromosomal locations to known disease translocations. Selected genes were experimentally validated across various haematological malignancy samples followed by stability comparison using geNorm, NormFinder, BestKeeper and RefFinder. (ii) 43 commonly used Reference Genes were obtained from literature through extensive systematic review. Levels of BCL2 mRNA was assessed by qPCR normalized either by novel reference genes from this study or GAPDH, the most cited reference gene in literature and compared. The analysis showed PTCD2, PPP1R3B and FBXW9 to be the most unregulated genes across lymph-nodes, bone marrow and PBMC samples unlike the Reference Genes used in literature. BCL2 mRNA level shows a consistent higher expression in haematological malignancy patients when normalized by these novel Reference Genes as opposed to GAPDH, the most cited Reference Gene. These reference genes should also be applicable in qPCR platforms using Taqman probes and other model systems including cell lines and rodent models. Absence of sample from healthy-normal individual in diagnostic cases call for careful selection of Reference Genes for relative quantification of a biomarker by qPCR.BCL2 can be used as molecular diagnostics only if normalized with a set of reference genes with stable yet low levels of expression across different types of haematological malignancies.


Assuntos
Biomarcadores Tumorais/isolamento & purificação , Neoplasias Hematológicas/diagnóstico , Proteínas Proto-Oncogênicas c-bcl-2/isolamento & purificação , RNA Mensageiro/isolamento & purificação , RNA-Seq/normas , Animais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Medula Óssea/patologia , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Modelos Animais de Doenças , Estudos de Viabilidade , Regulação Neoplásica da Expressão Gênica , Genes Essenciais , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Humanos , Leucócitos Mononucleares , Proteínas Proto-Oncogênicas c-bcl-2/sangue , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/sangue , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real/normas , Padrões de Referência
17.
PLoS One ; 15(8): e0236147, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797082

RESUMO

PURPOSE: A variety of visual and psychometric tests have been developed for assessing on-road driving performance and fitness to drive. The diagnostic power of a state of the art psychometric test battery (Vienna Test System) combined with a set of standard visual parameters recommended for assessing fitness to drive is investigated using an on-road driving test. The study aimed to determine whether a psychometric test battery could predict older adults' on-road driving performance. The relevance of visual standards required by law is discussed. METHODS: Vision impairment is more prevalent in later adulthood and many studies on visual and cognitive impact on driving safety and performance therefore focus on adults above 60 years of age. We therefore acquired an extensive set of driving-related visual and psychometric performance parameters in a group of elderly drivers (N = 84, median age 69, SD 6.6 years). Visual assessment included foveal acuity, perimetric field size, and dynamic aspects of peripheral vision (termed "PP") in the computer-based Vienna Test System (VTS; Schuhfried), as well as letter contrast thresholds in foveal and parafoveal vision in a separate setup. A selection of psychometric driving-aptitude tests that demonstrated the battery's capacity to predict aspects of driving performance and safety were further conducted on the VTS. Driving performance was assessed in a standardized on-road driving test. Two independent observers rated driving performance using a fixed scoring system assessing the number of driving errors in pre-defined traffic situations. In addition, globalized driving competence scores were assigned on a 6-point scale. RESULTS: The test battery performed excellent in identification of good drivers but failed in the prediction of bad driving performance. Visual performance indicators required by German law were less indicative of driving ability than psychometric assessment. Selective and divided attention turned out to be much more important for predicting fitness to drive than either visual acuity, size of the visual field, or contrast sensitivity. CONCLUSION: Predicting fitness to drive by means of visual and psychometric tests is an ambitious challenge. On the one hand sensitivity of a multi-disciplinary test-battery is too low to predict reliable driving ability in diagnostic settings which require an unambiguous interpretation of test results for individual drivers. Low sensitivity and low predictive values are incompatible with that objective. On the other hand, the results are valuable for a routine screening of fitness to drive. For that case, the assessment of attentional abilities in particular appears to be promising. Performance measures of divided and selective attention showed themselves to be the most predictive for fitness to drive in a sample pre-screened for clear visual deficits. Visual performance parameters required by law, in contrast, had no meaningful impact on driving performance, indicating a gap between mandatory regulations of state authorities and research results. Our results suggest that visual acuity tests designed for clinical diagnosis and monitoring of eye diseases should not at all be the choice for a screening of fitness to drive.


Assuntos
Acidentes de Trânsito/prevenção & controle , Atenção/fisiologia , Condução de Veículo/legislação & jurisprudência , Psicometria/métodos , Campos Visuais/fisiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Condução de Veículo/psicologia , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Testes Visuais/normas , Pessoas com Deficiência Visual/legislação & jurisprudência , Pessoas com Deficiência Visual/psicologia
18.
J Chromatogr A ; 1626: 461354, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797834

RESUMO

The Al-doped mesoporous crystalline material-41 (Al-MCM-41) composite was prepared and applied as fiber coating material of headspace solid-phase microextraction (HS-SPME) for extraction of polycyclic aromatic hydrocarbons (PAHs) from human urine. Five PAHs including acenaphthene, fluorene, phenanthrene, anthracene, and pyrene are chosen as target analytes to evaluate the performance of the material by GC-FID analysis. The mesoporous Al-MCM-41 composite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption measurement, and thermogravimetric analysis. The parameters affecting the extraction efficiency of HS-SPME were investigated. Under the optimal conditions, the method exhibits ideal linearity for target analytes in the range of 0.3-600 ng⋅mL-1 with the coefficients (R2) equal or higher than 0.9906. The enrichment factors are calculated from 540 to 1760. The limits of detection (LODs) and limits of quantitation (LOQs) are between the ranges of 0.06-0.18 and 0.3-0.9 ng⋅mL-1, respectively. The relative standard deviations (RSDs) (n = 5) of intra-day and inter-day are in the ranges of 1.08-7.49% and 2.84-18.3% respectively. The fiber-to-fiber reproducibility (n = 3) is in the range of 6.47-13.9%. The method was successfully applied for the analysis of PAHs in human urine with reasonable recoveries which is ranging from 73.29 to 116.1%.


Assuntos
Alumínio/química , Hidrocarbonetos Policíclicos Aromáticos/urina , Dióxido de Silício/química , Microextração em Fase Sólida/métodos , Adsorção , Cristalização , Humanos , Limite de Detecção , Masculino , Concentração Osmolar , Porosidade , Padrões de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Difração de Raios X
19.
J Chromatogr A ; 1626: 461355, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797835

RESUMO

Quantification of the gas streams from chemical systems such as catalytic reactors are routinely performed by on-line gas chromatography. Gas chromatographs used for this purpose are typically provided with a combination of thermal conductivity (TCD) and flame ionization (FID) detectors to be able to detect and quantify both permanent gases; COx, N2, H2, etc., and hydrocarbons. However, the accuracy of the quantification is hindered by the intrinsic limitations of each type of detector. Namely, TCD has low sensitivity and FID does not detect permanent gases. Therefore, modern gas chromatographs include methanizer units to partially overcome this shortcoming by converting COx to methane. However, as far as these authors know, the literature has not presented an analytical method to characterize gas streams with high accuracy by the simultaneous use of a combination of a TCD-FID detection system provided with a methanizer. This work is an attempt to solve this problematic; it consists of the formulation of a mathematical model for the well-known external and internal standard quantification methods in gas chromatography. The analysis of the gas stream from a catalytic reactor performing the combustion of methane was used to validate the developed method. The concentration ranges of the analysed gases were: 0.8-7.7 vol% of CH4, CO2, and CO, 7.7-38.5 vol.% of O2, and 46.2-90.8 vol.% of N2 at a total flow of 130 mL min-1. It was found that the commonly applied external standard method leads not only to inaccurate quantification but also to physically meaningless carbon balances and conclusions on the behaviour of the selected model system. In contrast, the internal standard method led to a highly accurate quantification with a physically meaningful carbon balance. Considering these findings, this contribution also draws attention to the need for a thoughtful application of chromatographic methods when studying the reactivity of gas systems.


Assuntos
Cromatografia Gasosa/métodos , Gases/análise , Sistemas On-Line , Carbono/análise , Catálise , Ionização de Chama , Metano/análise , Oxigênio/análise , Padrões de Referência , Reprodutibilidade dos Testes , Condutividade Térmica
20.
J Chromatogr A ; 1626: 461370, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797849

RESUMO

Betacyanins, natural plant pigments, from Iresine herbstii Hook. ex Lindl. leaf extract were separated for the first time by high-speed countercurrent chromatography (HSCCC) in a highly polar solvent system composed of PrOH-ACN-(NH4)2SO4satd.soln-H2O (1.0:0.5:1.2:1.0; v/v/v/v) in the tail-to-head mode. The flow rate of the mobile phase was 2.0 ml/min and the column rotation speed was 860 rpm. The retention of the stationary phase was 81.0%. For the identification of separated betacyanins in the crude extract and in the HSCCC fractions, as well as for the molecular formulas and multi-step fragmentation pattern elucidation, liquid chromatography with tandem mass spectrometry and high-resolution ion-trap time-of-flight mass spectrometry were performed. The innovative application of the HSCCC system for fractionation of the betacyanins present in I. herbstii leaves enabled effective separation as well as preconcentration of the pigments for further low- and high-resolution LC-MS/MS analysis. HSCCC separation enabled identification of 22 betacyanins, of which 18 had not been detected previously in the leaves of I. herbstii, and four of these betacyanins (sinapoyl-gomphrenin and coumaroyl-gomphrenin as well as their epimers) were identified for the first time in the Iresine genus.


Assuntos
Amaranthaceae/química , Betacianinas/análise , Distribuição Contracorrente/métodos , Solventes/química , Amaranthaceae/metabolismo , Betacianinas/isolamento & purificação , Betacianinas/normas , Cromatografia Líquida de Alta Pressão/normas , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Padrões de Referência , Espectrometria de Massas em Tandem/normas
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