RESUMEN
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak posed a challenge for diagnostic laboratories worldwide, with low-middle income countries (LMICs) being the most affected. The polymerase chain reaction (PCR) is the gold standard method for detecting SARS-CoV-2 infection. However, the challenge with this method is that it is expensive, which has resulted in under-testing for SARS-CoV-2 infection in many LMICs. Hence, this study aimed to compare and evaluate alternative methods for the mass testing of SARS-CoV-2 infection in laboratories with limited resources to identify cost-effective, faster, and accurate alternatives to the internationally approved kits. A total of 50 residual nasopharyngeal swab samples were used for evaluation and comparison between internationally approved kits (Thermo Fisher PureLink™ RNA Isolation Kit and Thermo Fisher TaqPath™ COVID-19 Assay Kit) and alternative methods (three RNA extraction and four commercial SARS-CoV-2 RT-PCR assay kits) in terms of the cost analysis, diagnostic accuracy, and turnaround time. In terms of performance, all of the alternative RNA extraction methods evaluated were comparable to the internationally approved kits but were more cost-effective (Lucigen QuickExtract™ RNA Extraction Kit, Bosphore EX-Tract Dry Swab RNA Solution and Sonicator method) and four commercial SARS-CoV-2 RT-PCR assay kits (Nucleic Acid COVID-19 Test Kit (SARS-CoV-2), abTESTM COVID-19 qPCR I Kit, PCL COVID19 Speedy RT-PCR Kit, and PCLMD nCoV One-Step RT-PCR Kit) with a sensitivity range of 76-100% and specificity of 96-100%. The cost per sample was reduced by more than 50% when compared to internationally approved kits. When compared to the Thermo Fisher PureLink™ Kit and Thermo Fisher TaqPath™ COVID-19 Assay Kit, the alternative methods had a faster turnaround time, indicating that laboratories with limited resources may be able to process more samples in a day. The above-mentioned cost-effective, fast, and accurate evaluated alternative methods can be used in routine diagnostic laboratories with limited resources for mass testing for SARS-CoV-2 because these were comparable to the internationally approved kits, Thermo Fisher PureLink™ Kit and Thermo Fisher TaqPath™ COVID-19 Assay Kit. The implementation of alternative methods will be the most cost-effective option for testing SARS-CoV-2 infection in LMICs.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Prueba de COVID-19 , Laboratorios , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Background: Diagnostic and therapeutic algorithms given by various societies for hepatitis B are fragmented and complex. The clinico-epidemiologic spectrum of hepatitis B is not studied with large-scale data from our region. We aimed to develop a comprehensive algorithm for the treatment of hepatitis B and study its clinico-epidemiological spectrum. Methods: From 2014-2019, the clinico-laboratory data of hepatitis B surface antigen (HbsAg)-positive patients were prospectively recorded. King George's Medical University hepatitis B therapeutic algorithm (KGHeBTA) was developed on the basis of the standard existing guidelines. The prevalence of different clinical stages of HBsAg-positive patients was calculated and their treatment records reviewed. Testing circumstances and risk factors were noted. Results: Among 1,508 data record sheets, 421 were complete. According to the KGHeBTA algorithm, 221 had detectable hepatitis B virus DNA. 21% were cirrhotic and 79% non-cirrhotic. 72% were incidentally detected asymptomatic hepatitis B, 7% were hepatitis B with acute symptoms, 0.7% were acute hepatitis B, and 22% were chronic hepatitis B. 20% patients were eligible for antivirals and 80% patients were not eligible. 32% patients were actually treated with antivirals due to the inclusion of some special indications as pregnancy and family history. Screening during various medical illnesses (40%) was the most common and during health camps (0.2%), the least common testing approach. Road-side shaving (52%) was the most common and intravenous drug abuse (0.2%) and the least common risk factor for the detection of hepatitis B in our data pool. Conclusions: HBsAg-positive patients can be easily worked up and treated based on the proposed algorithm (KGHeBTA). About one fourth to one fifth of all HBsAg-positive patients were eligible and treated with oral antivirals. Most of the patients were incidentally detected asymptomatic hepatitis B screened during medical illnesses. Roadside shaving and intravenous drug abuse were the most and the least common risk factors.
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Animal experimentation has been fundamental in biological and biomedical research. To guarantee the maximum quality, efficacy and/or safety of products intended for the use in humans in vivo testing is necessary; however, for over 60 years, alternative methods have been developed in response to the necessity to reduce the number of animals used in experimentation, to guarantee their welfare; resorting to animal models only when strictly necessary. The three Rs (Replacement, Reduction, and Refinement), seek to ensure the rational and respectful use of laboratory animals and maintain an adequate projection in terms of bioethical considerations. This article describes different approaches to apply 3Rs in preclinical experimentation for either research or regulatory purposes.
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Alternativas al Uso de Animales/métodos , Simulación por Computador , Evaluación Preclínica de Medicamentos , Técnicas In Vitro , Animales , Investigación Biomédica , Aprobación de Drogas , Desarrollo de MedicamentosRESUMEN
The ongoing debate concerning the regulation of endocrine disruptors, has increasingly led to questions concerning the current testing of chemicals and whether this is adequate for the assessment of potential endocrine disrupting effects. This paper describes the current testing approaches for plant protection product (PPP) active substances in the European Union and the United States and how they relate to the assessment of endocrine disrupting properties for human and environmental health. This includes a discussion of whether the current testing approaches cover modalities other than the estrogen, androgen, thyroid and steroidogenesis (EATS) pathways, sensitive windows of exposure, adequate assessment of human endocrine disorders and wildlife species, and the determination of thresholds for endocrine disruption. It is concluded, that the scope and nature of the core and triggered data requirements for PPP active substances are scientifically robust to address adverse effects mediated through endocrine mode(s) of action and to characterise these effects in terms of dose response.
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Agroquímicos/toxicidad , Disruptores Endocrinos/toxicidad , Regulación Gubernamental , Legislación como Asunto/tendencias , Toxicología/legislación & jurisprudencia , Toxicología/métodos , Animales , Animales Salvajes , Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Contaminación Ambiental/legislación & jurisprudencia , HumanosRESUMEN
Positive results in the Ames/E. coli bacterial mutagenicity assay create a significant hurdle for the development of new products/drugs and as a result, most companies drop mutagenic ingredients from further development. One important consequence of this is that the understanding of the human relevance of chemicals that are positive in the Ames assay is not increasing at the pace seen with ingredients that are positive in the other in vitro genotoxicity assays. Recent advances in defining thresholds for mutagenic carcinogens, along with new assays for measuring mutagenicity in vivo suggests it is time to direct more attention to the holy grail of clearly defining practical approaches to address positive results in the Ames assay. To stimulate further discussion and research in this area, a review of the most current thinking on approaches for dealing with Ames positive results is provided along with some suggestions for the way forward.