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1.
San Salvador; MINSAL; sept. 28, 2024. 12 p. ilus.
Não convencional em Espanhol | BISSAL, LILACS | ID: biblio-1566994

RESUMO

El objetivo de la ruta es establecer las pautas formales, respecto a la atención integral en salud en las niñas, niños y adolescentes, ayudando a optimizar las acciones, disminuir costos, incrementar la satisfacción de los usuarios, así como mejorar la productividad y competitividad del personal de salud. En razón de lo anterior presentamos la ruta de trabajo, para la adecuación de la normativa técnica, producto del trabajo de las diferentes dependencias vinculadas directa e indirectamente a la atención en salud a niñas, niños y adolescentes


The objective of the route is to establish formal guidelines regarding comprehensive health care in the girls, boys and adolescents, helping to optimize actions, reduce costs, increase user satisfaction, as well as improving the productivity and competitiveness of health personnel. Due to the above, we present the work route, for the adaptation of the technical regulations, product of the work of the different agencies linked directly and indirectly to care in health for girls, boys and adolescents


Assuntos
Padrões de Referência , Jurisprudência , El Salvador
2.
Sci Rep ; 14(1): 19259, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164314

RESUMO

Radiomics features (RFs) serve as quantitative metrics to characterize shape, density/intensity, and texture patterns in radiological images. Despite their promise, RFs exhibit reproducibility challenges across acquisition settings, thus limiting implementation into clinical practice. In this investigation, we evaluate the effects of different CT scanners and CT acquisition protocols (KV, mA, field-of-view, and reconstruction kernel settings) on RFs extracted from lumbar vertebrae of a cadaveric trunk. Employing univariate and multivariate Generalized Linear Models (GLM), we evaluated the impact of each acquisition parameter on RFs. Our findings indicate that variations in mA had negligible effects on RFs, while alterations in kV resulted in exponential changes in several RFs, notably First Order (94.4%), GLCM (87.5%), and NGTDM (100%). Moreover, we demonstrated that a tailored GLM model was superior to the ComBat algorithm in harmonizing CT images. GLM achieved R2 > 0.90 in 21 RFs (19.6%), contrasting ComBat's mean R2 above 0.90 in only 1 RF (0.9%). This pioneering study unveils the effects of CT acquisition parameters on bone RFs in cadaveric specimens, highlighting significant variations across parameters and scanner datasets. The proposed GLM model presents a robust solution for mitigating these differences, potentially advancing harmonization efforts in Radiomics-based studies across diverse CT protocols and vendors.


Assuntos
Cadáver , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Vértebras Lombares/diagnóstico por imagem , Reprodutibilidade dos Testes , Padrões de Referência , Radiômica
3.
Sci Rep ; 14(1): 17828, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090210

RESUMO

The liver plays a vital role in lipid synthesis and metabolism in poultry. To study the functional genes more effectively, it is essential to screen of reliable reference genes in the chicken liver, including females, males, embryos, as well as the Leghorn Male Hepatoma (LMH) cell line. Traditional reference gene screening involves selecting commonly used housekeeping genes (HKGs) for RT-qPCR experiments and using different algorithms to identify the most stable ones. However, this approach is limited in selecting the best reference gene from a small pool of HKGs. High-throughput sequencing technology may offer a solution to this limitation. This study aimed to identify the most consistently expressed genes by utilizing multiple published RNA-seq data of chicken liver and LMH cells. Subsequently, the stability of the newly identified reference genes was assessed in comparison to previously validated stable poultry liver expressed reference genes and the commonly employed HKGs using RT-qPCR. The findings indicated that there is a higher degree of similarity in stable expression genes between female and male liver (such as LSM14A and CDC40). In embryonic liver, the optimal new reference genes were SUDS3, TRIM33, and ERAL1. For LMH cells, the optimal new reference genes were ALDH9A1, UGGT1, and C21H1orf174. However, it is noteworthy that most HKGs did not exhibit stable expression across multiple samples, indicating potential instability under diverse conditions. Furthermore, RT-qPCR experiments proved that the stable expression genes identified from RNA-seq data outperformed commonly used HKGs and certain validated reference genes specific to poultry liver. Over all, this study successfully identified new stable reference genes in chicken liver and LMH cells using RNA-seq data, offering researchers a wider range of reference gene options for RT-qPCR in diverse situations.


Assuntos
Galinhas , Genes Essenciais , Fígado , Reação em Cadeia da Polimerase em Tempo Real , Padrões de Referência , Animais , Galinhas/genética , Fígado/metabolismo , Masculino , Feminino , Reação em Cadeia da Polimerase em Tempo Real/normas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Perfilação da Expressão Gênica/normas , Perfilação da Expressão Gênica/métodos , Linhagem Celular Tumoral , Embrião de Galinha
4.
Artigo em Inglês | MEDLINE | ID: mdl-39094679

RESUMO

MicroRNAs play crucial regulatory roles in various aspects of development and physiology, including environmental adaptation and stress responses in teleosts. RT-qPCR is the most commonly used method for studying microRNA expression, with the accuracy and reliability of results depending on the use of an appropriate reference gene for normalization. This study aimed to evaluate seven miRNAs (U6, Let-7a, miR-23a, miR-25-3, miR-103, miR-99-5, and miR-455) expression stability in different tissues of Nile tilapia subjected to osmotic stress. Fish were divided into two groups: a control and an experimental group, raised in 0 and 12 ppt salinity water respectively. After 21 days, brain, gills, liver, and posterior intestine were collected for analysis. Different mathematical algorithms (geNorm, NormFinder, BestKeeper, and the comparative ΔCt method) were employed to identify the most suitable reference miRNAs. The results indicate that the miR-455/miR-23a combination is a robust reference for normalizing miRNA expression levels in studies of osmotic stress responses in Nile tilapia. The stability of miRNA expression can vary depending on specific stress conditions and biological processes, underscoring the necessity of selecting appropriate normalizing miRNAs for each experimental context. This study identifies reliable reference genes for future RT-qPCR analyses of miRNA expression, thereby enhancing our understanding of molecular responses in fish to environmental challenges. These insights are fundamental to the development of new technologies for the improved management and sustainability of aquaculture practices.


Assuntos
Ciclídeos , MicroRNAs , Pressão Osmótica , Reação em Cadeia da Polimerase em Tempo Real , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Ciclídeos/genética , Ciclídeos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/normas , Padrões de Referência
5.
Mol Biol Rep ; 51(1): 922, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39162931

RESUMO

BACKGROUND: A correct and stably expressing reference gene is prerequisite for successful quantitative real-time PCR (qRT-PCR). Investigating gene expression profiling during flower development could enhance our understanding of the molecular mechanisms of flower formation and fertility in Lycium. METHODS AND RESULTS: In this study, 11 candidate reference genes in Lycium flower development were selected from transcriptome sequence data and evaluated with five traditional housekeeping genes from previous studies based on qRT-PCR amplification. Comparing the expression stability result of 16 candidate genes using GeNorm, NormFinder, BestKeeper, and Delta Ct algorithms, Lba04g01649 and Lba12g02820 were validated as the optimal reference genes for the flower development of Lycium. CONCLUSIONS: The reference genes identified in this study would improve the accuracy of qRT-PCR quantification of target gene expression in Lycium flower development and facilitate future functional genomics studies on flower development. This research could lay the foundation for the study of the reproduction and development of the Lycium flower.


Assuntos
Flores , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Lycium , Reação em Cadeia da Polimerase em Tempo Real , Padrões de Referência , Lycium/genética , Lycium/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Regulação da Expressão Gênica de Plantas/genética , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Transcriptoma/genética , Genes Essenciais/genética , Hibridização Genética
6.
BMC Genomics ; 25(1): 697, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014352

RESUMO

BACKGROUND: Real-time quantitative PCR (RT-qPCR) is one of the most widely used gene expression analyses for validating RNA-seq data. This technique requires reference genes that are stable and highly expressed, at least across the different biological conditions present in the transcriptome. Reference and variable candidate gene selection is often neglected, leading to misinterpretation of the results. RESULTS: We developed a software named "Gene Selector for Validation" (GSV), which identifies the best reference and variable candidate genes for validation within a quantitative transcriptome. This tool also filters the candidate genes concerning the RT-qPCR assay detection limit. GSV was compared with other software using synthetic datasets and performed better, removing stable low-expression genes from the reference candidate list and creating the variable-expression validation list. GSV software was used on a real case, an Aedes aegypti transcriptome. The top GSV reference candidate genes were selected for RT-qPCR analysis, confirming that eiF1A and eiF3j were the most stable genes tested. The tool also confirmed that traditional mosquito reference genes were less stable in the analyzed samples, highlighting the possibility of inappropriate choices. A meta-transcriptome dataset with more than ninety thousand genes was also processed successfully. CONCLUSION: The GSV tool is a time and cost-effective tool that can be used to select reference and validation candidate genes from the biological conditions present in transcriptomic data.


Assuntos
Reação em Cadeia da Polimerase em Tempo Real , Padrões de Referência , Software , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Animais , RNA-Seq/métodos , RNA-Seq/normas , Perfilação da Expressão Gênica/métodos , Transcriptoma
7.
Commun Biol ; 7(1): 873, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020054

RESUMO

Causal gene discovery methods are often evaluated using reference sets of causal genes, which are treated as gold standards (GS) for the purposes of evaluation. However, evaluation methods typically treat genes not in the GS positive set as known negatives rather than unknowns. This leads to inaccurate estimates of sensitivity, specificity, and AUC. Labeling biases in GS gene sets can also lead to inaccurate ordering of alternative causal gene discovery methods. We argue that the evaluation of causal gene discovery methods should rely on statistical techniques like those used for variant discovery rather than on comparison with GS gene sets.


Assuntos
Padrões de Referência , Humanos , Bases de Dados Genéticas
8.
Biometrics ; 80(3)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38994641

RESUMO

This article addresses the challenge of estimating receiver operating characteristic (ROC) curves and the areas under these curves (AUC) in the context of an imperfect gold standard, a common issue in diagnostic accuracy studies. We delve into the nonparametric identification and estimation of ROC curves and AUCs when the reference standard for disease status is prone to error. Our approach hinges on the known or estimable accuracy of this imperfect reference standard and the conditional independent assumption, under which we demonstrate the identifiability of ROC curves and propose a nonparametric estimation method. In cases where the accuracy of the imperfect reference standard remains unknown, we establish that while ROC curves are unidentifiable, the sign of the difference between two AUCs is identifiable. This insight leads us to develop a hypothesis-testing method for assessing the relative superiority of AUCs. Compared to the existing methods, the proposed methods are nonparametric so that they do not rely on the parametric model assumptions. In addition, they are applicable to both the ROC/AUC analysis of continuous biomarkers and the AUC analysis of ordinal biomarkers. Our theoretical results and simulation studies validate the proposed methods, which we further illustrate through application in two real-world diagnostic studies.


Assuntos
Área Sob a Curva , Simulação por Computador , Curva ROC , Humanos , Padrões de Referência , Estatísticas não Paramétricas , Biomarcadores/análise , Modelos Estatísticos
9.
Pharmeur Bio Sci Notes ; 2024: 76-89, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38949845

RESUMO

The level of anti-D antibodies in human immunoglobulin products for intravenous administration (IVIG) is controlled by the direct haemagglutination method prescribed by the European Pharmacopoeia (Ph. Eur.) that requires 2 control reference reagents. The World Health Organization (WHO) positive control International Reference Reagent (IRR; 02/228) with a nominal titre of 8 defines the highest acceptable titre, while the negative control preparation (02/226) has a nominal titre of <2. Working reference preparations (04/132 and 04/140) were subsequently established as Biological Reference Preparations (BRPs) for the Ph. Eur., and for distribution by the United States Food and Drug Administration (US FDA) and the National Institute for Biological Standards and Control (NIBSC). Due to diminishing stocks of these working reference preparations across the 3 institutions, a joint international study was organised to establish harmonised replacement batches. Sixteen laboratories contributed data to the study to evaluate positive and negative candidate replacement batches (13/148 and 12/300, respectively) against the WHO positive and negative control IRRs and the current working reference preparations (BRPs). The results show that the candidate reference preparations (13/148 and 12/300) are indistinguishable from the corresponding IRRs and current BRPs. The candidate preparations 13/148 and 12/300 were adopted by the Ph. Eur. Commission as Immunoglobulin (anti-D antibodies test) BRP batch 2 and Immunoglobulin (anti-D antibodies test negative control) BRP batch 2 with nominal haemagglutination titres of 8 and <2, respectively. The same materials were also adopted as NIBSC and US FDA reference preparations, thus ensuring full harmonisation.


Assuntos
Padrões de Referência , Humanos , Imunoglobulinas Intravenosas/normas , Imunoglobulinas Intravenosas/farmacologia , Imunoglobulinas Intravenosas/análise , Imunoglobulina rho(D) , Química Farmacêutica/normas , Química Farmacêutica/métodos
10.
Pharmeur Bio Sci Notes ; 2024: 106-126, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39010792

RESUMO

An international collaborative study was jointly organised by the World Health Organization (WHO) and the European Directorate for the Quality of Medicines & HealthCare (EDQM) to establish the WHO 3rd International Standard (IS) for Prekallikrein activator (PKA) and European Pharmacopoeia (Ph. Eur.) PKA in albumin Biological Reference Preparation (BRP) batch 7. Twenty-six laboratories took part in the study to calibrate these replacement batches, as well as an additional reserve batch for the WHO IS, against the current WHO 2nd IS for PKA (02/168). Ph. Eur. PKA in albumin BRP batch 6 was also included to evaluate the continuity of the consecutive batches of BRP. The centrally calculated overall Huber's means based on the results from laboratories with at least two valid assays were 29.6 and 29.6 IU/ampoule for the candidate WHO 3rd IS (Sample A) and reserve batch (Sample B), and were 38.4 and 37.0 IU/vial for the current BRP batch 6 (Sample C) and the candidate BRP batch 7 (Sample D). The intra-laboratory variation expressed as coefficient of variation (CV) ranged between 1.4 and 16.6 %. The inter-laboratory variation expressed as CV based on Huber's means ranged between 4.4 and 5.4 %. The Huber's mean activity of Sample D against Sample C was 36.6 IU/vial with a CV of 1.7 %. These results confirm the good continuity of the consecutive batches of BRP. Based on the results of this study, it is recommended to establish Sample A as the WHO 3rd IS for PKA with an assigned potency of 30 IU/ampoule and Sample D as the Ph. Eur. PKA in albumin BRP batch 7 with an assigned potency of 37 IU/vial. Sample B is intended to be kept as a future reserve replacement WHO IS.


Assuntos
Padrões de Referência , Organização Mundial da Saúde , Humanos , Europa (Continente) , Cooperação Internacional , Albuminas/normas , Farmacopeias como Assunto/normas
11.
Eur J Orthod ; 46(4)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39066623

RESUMO

BACKGROUND: The robustness and credibility of RT-qPCR results are critically dependent on the selection of suitable reference genes. However, the mineralization of the extracellular matrix can alter the intracellular tension and energy metabolism within cells, potentially impacting the expression of traditional reference genes, namely Actb and Gapdh. OBJECTIVE: To methodically identify appropriate reference genes for research focused on mouse cementoblast mineralization. MATERIALS AND METHODS: Time-series transcriptomic data of mouse cementoblast mineralization were used. To ensure expression stability and medium to high expression levels, three specific criteria were applied to select potential reference genes. The expression stability of these genes was ranked based on the DI index (1/coefficient of variation) to identify the top six potential reference genes. RT-qPCR validation was performed on these top six candidates, comparing their performance against six previously used reference genes (Rpl22, Ppib, Gusb, Rplp0, Actb, and Gapdh). Cq values of these 12 genes were analyzed by RefFinder to get a stability ranking. RESULTS: A total of 4418 (12.27%) genes met the selection criteria. Among them, Rab5if, Chmp4b, Birc5, Pea15a, Nudc, Supt4a were identified as candidate reference genes. RefFinder analyses revealed that two candidates (Birc5 and Nudc) exhibited superior performance compared to previously used reference genes. LIMITATIONS: RefFinder's stability ranking does not consider the influence of primer efficiency. CONCLUSIONS AND IMPLICATIONS: We propose Birc5 and Nudc as candidate reference genes for RT-qPCR studies investigating mouse cementoblast mineralization and cementum repair.


Assuntos
Cemento Dentário , Reação em Cadeia da Polimerase em Tempo Real , Survivina , Animais , Camundongos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Survivina/genética , Padrões de Referência , RNA-Seq/métodos , RNA-Seq/normas , Calcificação Fisiológica/genética
12.
Funct Plant Biol ; 512024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39038159

RESUMO

CONSTANS-LIKE (COL ) genes are a key signalling molecule that regulates plant growth and development during the photoperiod. Our preliminary experiments showed that the photoperiod greatly influence the formation of Tetrastigma hemsleyanum root tubers. In this study, we examined the oscillation patterns and expression characteristics of COL genes in leaves of T. hemsleyanum under different photoperiod conditions. Six genes were selected as candidate reference genes for further analyses: (1) 18S ribosomal RNA (18S rRNA ); (2) α-tubulin (TUBA ); (3) 30S ribosomal RNA (30S rRNA ); (4) TATA binding protein (TBP ); (5) elongation factor 1α (EF-1α ); and (6) RNA polymerase II (RPII ). The geNorm, NormFinder, and BestKeeper software programs were used to evaluate expression stability. Two ThCOL genes were screened in the T. hemsleyanum transcriptome library, and their expression patterns under different photoperiod conditions were analysed using quantitative reverse transcription PCR. The genes EF-1α , TUBA , and 18S rRNA were used to analyse the expression profiles of CONSTANS genes (ThCOL4 and ThCOL5 ) under different photoperiods. The expression peaks of ThCOL4 and ThCOL5 appeared at different times, demonstrating that their oscillation patterns were influenced by the photoperiod. We speculate that these two ThCOL genes may be involved in different biological processes.


Assuntos
Regulação da Expressão Gênica de Plantas , Fotoperíodo , Proteínas de Plantas , Vitaceae , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Vitaceae/genética , Genes de Plantas , Perfilação da Expressão Gênica , Folhas de Planta/genética , Folhas de Planta/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Padrões de Referência
13.
J Clin Lab Anal ; 38(13-14): e25082, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39072781

RESUMO

In vivo studies offer a detailed understanding of organism functioning, surpassing the insights provided by in vitro studies. These experiments are crucial for comprehending disease emergence, progression, and associated mechanisms in humans, as well as for developing treatments. When choosing experimental models, factors such as genomic similarity, physiological relevance, ethical appropriateness, and economic feasibility must be considered. Standardized protocols enhance the reliability, and reproducibility of scientific methods, promoting the assessment of research in the scientific literature. Researchers conducting embryo studies should establish and document standardized protocols for increased data comparability. Standardization is vital for scientific validity, reproducibility, and comparability in both in vivo and in vitro studies, ensuring the accuracy and reliability of experimental results and advancing scientific knowledge.


Assuntos
Embrião de Mamíferos , Humanos , Animais , Técnicas de Cultura Embrionária/normas , Técnicas de Cultura Embrionária/métodos , Padrões de Referência , Modelos Biológicos , Reprodutibilidade dos Testes , Pesquisas com Embriões/ética
14.
Anal Bioanal Chem ; 416(22): 4897-4906, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38953919

RESUMO

A candidate reference measurement procedure (RMP) for serum theophylline via isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. With a single-step precipitation pretreatment and a 6-min gradient elution, the method achieved baseline separation of theophylline and its analogs on a C18-packed column. A bracketing calibration method was used to ensure repeatable signal intensity and high measurement precision. The intra-assay and inter-assay imprecisions were 1.06%, 0.84%, 0.72% and 0.47%, 0.41%, 0.25% at concentrations of 4.22 µg/mL (23.40 µmol/L), 8.45 µg/mL (46.90 µmol/L), and 15.21 µg/mL (84.43 µmol/L), respectively. Recoveries ranged from 99.35 to 102.34%. The limit of detection (LoD) was 2 ng/mL, and the lowest limit of quantification (LLoQ) was 5 ng/mL. The linearity range extended from 0.47 to 60 µg/mL (2.61-333.04 µmol/L). No ion suppression and carry-over (< 0.68%) were observed. The relative bias for this candidate RMP that participated in 2023 External Quality Control for Reference Laboratories (RELA) conducted by the International Federation of Clinical Chemistry (IFCC) was within a range of 0.17 to 0.93%. Furthermore, two clinical immunoassay systems were compared with this candidate RMP, demonstrating good correlations. The results of the Trueness Verification Plan indicate significant differences among routine systems, highlighting the need for standardization efforts. The developed candidate RMP for serum theophylline serves as a precise reference baseline for standardizing clinical systems and assigning values to reference materials.


Assuntos
Limite de Detecção , Espectrometria de Massas em Tandem , Teofilina , Teofilina/sangue , Espectrometria de Massas em Tandem/métodos , Humanos , Calibragem , Cromatografia Líquida/métodos , Padrões de Referência , Técnicas de Diluição do Indicador , Reprodutibilidade dos Testes
15.
J Environ Radioact ; 278: 107499, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39079350

RESUMO

Certified reference material (CRM) for natural (40K,210Pb,210Po,226Ra,228Ra,228Th,230Th,232Th,234U,235U, and238U) and anthropogenic (137Cs,239+240Pu, and241Am) radionuclides in marine sediment from the Baltic Sea (IAEA-465) has been developed. Information values are given for 238Pu,239Pu and240Pu. Altogether 27 laboratories participated in this exercise. Radiometric (alpha-spectrometry, gamma-spectrometry and beta counting, as well as mass spectrometry (ICP-MS and AMS) techniques were applied in measurements. The CRM is intended to be used for Quality Assurance/Quality Control of radionuclide analyses, for the development and validation of analytical methods, for the development of reference methods and for training purposes.


Assuntos
Sedimentos Geológicos , Monitoramento de Radiação , Poluentes Radioativos da Água , Sedimentos Geológicos/química , Poluentes Radioativos da Água/análise , Plutônio/análise , Padrões de Referência , Radioisótopos/análise , Radioisótopos de Césio/análise , Tório/análise
16.
J Pharm Biomed Anal ; 249: 116344, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39053096

RESUMO

The performance of analytical test methods is critical to ensure decisions that affect efficacy and quality of pharmaceutical products are based on accurate and reliable results. As described in USP <1220> and advocated for in ICH Q14, continued verification of critical method attributes linked to bias and precision is essential to ensure method performance throughout the lifecycle of an analytical test method. As continued verification programs for analytical methods within the pharmaceutical industry mature, additional monitoring tools are required to deliver robust and cost-effective verification programs. Herein, a novel methodology is presented to evaluated analytical method variability directly from results generated during routine method execution. The implementation of the methodology is demonstrated for a small molecule liquid chromatographic assay method utilizing a single-point external reference calibration. Approaches to reduce the required data to be collected and broaden the applicability of the methodology to a wide range of analytical methods is described. Finally, the application of the methodology to method development activities is discussed to aid in the identification of variability sources and effectively select replication strategies, thus allowing a holistic understanding of method variability throughout the entirety of the method lifecycle.


Assuntos
Controle de Qualidade , Calibragem , Reprodutibilidade dos Testes , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Cromatografia Líquida/métodos , Padrões de Referência , Indústria Farmacêutica/métodos , Técnicas de Química Analítica/métodos
17.
Nat Commun ; 15(1): 6167, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039053

RESUMO

Translating RNA-seq into clinical diagnostics requires ensuring the reliability and cross-laboratory consistency of detecting clinically relevant subtle differential expressions, such as those between different disease subtypes or stages. As part of the Quartet project, we present an RNA-seq benchmarking study across 45 laboratories using the Quartet and MAQC reference samples spiked with ERCC controls. Based on multiple types of 'ground truth', we systematically assess the real-world RNA-seq performance and investigate the influencing factors involved in 26 experimental processes and 140 bioinformatics pipelines. Here we show greater inter-laboratory variations in detecting subtle differential expressions among the Quartet samples. Experimental factors including mRNA enrichment and strandedness, and each bioinformatics step, emerge as primary sources of variations in gene expression. We underscore the profound influence of experimental execution, and provide best practice recommendations for experimental designs, strategies for filtering low-expression genes, and the optimal gene annotation and analysis pipelines. In summary, this study lays the foundation for developing and quality control of RNA-seq for clinical diagnostic purposes.


Assuntos
Benchmarking , Biologia Computacional , Controle de Qualidade , RNA-Seq , Padrões de Referência , Benchmarking/métodos , Humanos , RNA-Seq/métodos , RNA-Seq/normas , Biologia Computacional/métodos , Reprodutibilidade dos Testes , Análise de Sequência de RNA/métodos , Análise de Sequência de RNA/normas , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
18.
Pharmeur Bio Sci Notes ; 2024: 90-105, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38967620

RESUMO

Human immunoglobulin products are used for the treatment of a number of diseases, such as primary or secondary immunodeficiencies and autoimmune conditions due to the complete absence of antibodies or the production of defective immunoglobulins. Quality control of human immunoglobulin products is essential to ensure therapeutic functionality and safety. This includes testing for Fc function and anticomplementary activity (ACA), as well as verification of appropriate molecular size distribution using size-exclusion chromatography as prescribed in the European Pharmacopoeia (Ph. Eur.) monographs 0338, 0918, 2788 and 1928. To this end, specific biological reference preparations (BRPs) must be used. Stocks of the Ph. Eur. Human immunoglobulin (molecular size) BRP were running low and therefore a collaborative study was run by the European Directorate for the Quality of Medicines & HealthCare (EDQM), under the aegis of the Biological Standardisation Programme, to calibrate replacement batches. Eighteen laboratories, including manufacturers and Official Medicines Control Laboratories, took part in the study. Three batches of candidate BRPs were assessed and compared to Ph. Eur. Human immunoglobulin (molecular size) BRP 3 to ensure continuity. Based on the study results, the candidate BRPs were adopted by the Ph. Eur. Commission as Ph. Eur. Human immunoglobulin (molecular size) BRP batch 4, 5 and 6.


Assuntos
Imunoglobulinas , Controle de Qualidade , Humanos , Imunoglobulinas/análise , Padrões de Referência , Cromatografia em Gel/normas , Peso Molecular , Europa (Continente)
20.
J Am Soc Mass Spectrom ; 35(8): 1726-1732, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38953246

RESUMO

Extracts prepared from the seeds of the medicinal plant milk thistle [Silybum marianum (L.) Gaertn. (Asteraceae)] are widely used as dietary supplements due to anti-inflammatory, antitumor, and hepatoprotective effects. Called silymarin, the main components of lipophilic extracts of milk thistle seeds are flavonoids and flavonolignans including silybin A, silybin B, isosilybin A, isosilybin B, silydianin, silychristin, taxifolin, and 2,3-dehydrosilybins. The aim of this study was to develop a method based on UHPLC-MS/MS for the chemical authentication and standardization of milk thistle silymarin. Validation included the method of standard addition to account for the lack of a blank matrix. Potential matrix effects were investigated by analyzing silymarin standards dissolved only in the initial UHPLC mobile phase. Measurements of six flavonolignans and taxifolin in the milk thistle extract using UHPLC-MS/MS with standard addition or external standard calibration produced similar results for all analytes except silydianin and 2,3-dehydrosilybin B, which showed significant peak enhancement during negative ion electrospray due to botanical matrix effects. The UHPLC-MS/MS-based method of standard addition requires <10 min per injection and is suitable for the standardization of silymarin from milk thistle in support of preclinical and clinical studies of safety and efficacy.


Assuntos
Extratos Vegetais , Silybum marianum , Silimarina , Espectrometria de Massas em Tandem , Silybum marianum/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Extratos Vegetais/análise , Silimarina/análise , Silimarina/química , Silimarina/análogos & derivados , Reprodutibilidade dos Testes , Flavonolignanos/análise , Flavonolignanos/química , Flavonolignanos/normas , Padrões de Referência , Limite de Detecção , Quercetina/análogos & derivados
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