28 research outputs found
Resveratrol and radiation biological effects
Resveratrol is a phytoalexin, a phenolic compound present in wines and several plants. This compound is related to a broad spectrum of biological activities such as antioxidant and anticarcinogenic effects that are very important in prevention of cancer, cardiovascular diseases and other diseases caused by oxidative processes. Over the last years, biological effects of ionizing radiation in the presence of resveratrol have been studied in different cell cultures. The aim of this study was to verify the effect of gamma radiation on mouse connective tissue cells (NCTC clone 929) in culture in the presence of trans-resveratrol. Cell viabilities were analyzed by neutral red uptake assay. The results demonstrated in vitro the radioprotective effect of trans-resveratrol on cell culture and it was more pronounced when cell culture was irradiated at 500-800 Gy doses in the presence of resveratrol concentrations between 12.5 and 25 μM. These results provide evidence that trans-resveratrol alters the cellular response to ionizing radiation, expanding the knowledge of resveratrol biological properties in physiological and pathological processes, contributing to the development of future studies about the possibility of including resveratrol and its derivatives in dietary supplements given to cancer patients during radiotherapy
Avaliação da biocompatibilidade de implantes mamários de silicone esterilizados por calor seco e pelo óxido de etileno
Os implantes mamários de silicone têm sido empregados, tanto nas cirurgias de aumento de mama, quanto na reconstrução do tecido mamário. A segurança biológica deste tipo de implante deve ser garantida, pois, em função da esterilização estes materiais, podem sofrer alterações oriundas dos processos esterilizantes por comprometimento da estrutura química dos polímeros. O objetivo deste trabalho consistiu na avaliação da biocompatibilidade de implantes mamários preenchidos com gel de silicone, de superfície lisa e texturizada submetidos à esterilização por calor seco e óxido de etileno. Empregou-se, para tanto, método in vitro, avaliando a citotoxicidade pelo método de captura do vermelho neutro, utilizando a linhagem celular NCTC clone 929. Os resultados obtidos demonstraram não haver comprometimento da biocompatibilidade dos biomateriais submetidos aos dois processos (calor seco e óxido de etileno), assim como comprovaram a eficácia de ambos na esterilização dos implantes.Silicone breast implants have been widely used for mammary augmentation and reconstruction surgery. Biological safety of these implants can be altered by sterilization methods. This study consisted of the biocompatibility assessment of smooth and textured silicone gel breast implants sterilized by dry-heat and ethylene oxide through cell viability, employing neutral red uptake method. The NCTC clone 929 cell were employed and the results showed no cytotoxicity of implants after both sterilization processes
Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama
Do materials sterilized using gamma rays become toxic when re-sterilized in ethylene oxide? This question guided the objective of this study, which was to investigate the potential cytotoxic effect of PVC sterilized by gamma radiation and re-sterilized with EO by the agar diffusion method in cell cultures. Nine PVC tubes were subjected to gamma radiation sterilization and were re-sterilized in EO. The tubes were divided into a total of 81 units of analysis that were tested so as to represent the internal and external surfaces and mass of each tube. It was concluded that the PVC materials sterilized in gamma radiation and re-sterilized in EO are not cytotoxic.Los materiales esterilizados con rayos gama, al ser re-esterilizados en óxido de etileno (EO), ¿forman substancias tóxicas? Esta pregunta orientó el objetivo del presente estudio, que fue investigar el potencial efecto citotóxico del PVC esterilizado en radiación gamma y re-esterilizado en EO por el método de difusión en agar en cultivos celulares. Nueve tubos de PVC fueron sometidos a esterilización por radiación gamma y re-esterilizados en EO. Se les aplicaron en total 81 unidades de análisis, las cuales fueron testeadas de manera tal de representar las superficies internas, externas y la masa de cada tubo. Se concluyó en que los materiales de PVC esterilizados con Radiación Gamma y, posteriormente, con EO, no son citotóxicos.Materiais esterilizados em raios gama, ao serem re-esterilizados em óxido de etileno (EO), formam substâncias tóxicas? Esta questão norteou o objetivo deste estudo, que foi investigar o potencial efeito citotóxico do PVC esterilizado em radiação gama e re-esterilizado em EO pelo método da difusão em ágar em culturas celulares. Nove tubos de PVC foram submetidos à esterilização em radiação gama e re-esterilizados em EO. Os tubos foram divididos em um total de 81 unidades de análise, que foram testadas de forma a representar as superfícies internas, externas e massa de cada tubo. Concluiu-se que os materiais de PVC esterilizados em Radiação Gama e consecutivamente re-esterilizados em EO não são citotóxicos
Determination of the biological reactivity of ketoconazole in shampoo: draize eye test and cytotoxity test
Cetoconazol é um agente antifúngico, que pode ser incorporado em diferentes formas farmacêuticas, como, por exemplo, xampus e cremes. O objetivo do trabalho foi avaliar a segurança biológica in vivo (teste de irritação ocular) e in vitro (teste de citotoxicidade) do xampu de cetoconazol degradado sob ação da luz. Para tanto, a formulação foi exposta à radiação UV-C (254 nm) e foram empregados dois métodos para a determinação quantitativa do cetoconazol: CLAE e ensaio microbiológico. Os resultados demonstraram alteração do cetoconazol em presença da luz - presença de picos secundários no cromatograma e diminuição da atividade antifúngica - entretanto, não demonstraram alteração na segurança biológica entre xampu de cetoconazol e xampu de cetoconazol contendo produtos de degradação.Ketoconazole is an antifungal agent and can be incorporated into several dosage forms, as an example it could be mentioned shampoos and creams. The aim of this work was to assess the biological reactivity in vivo (Draize eye test) and in vitro (cytotoxity test) of ketoconazole in shampoo degradeted under action of light. The formulation was exposed to UV-C (254 nm) radiation and two methods were used for the quantitative determination of ketoconazole: HPLC and microbiological assay. The results showed alteration in ketoconazole in presence of light - secondary peaks in chromatogram and decrease in antifungal activity - however, no alteration on the biological reactivity between ketoconazole shampoo and ketoconazole shampoo containing degradation products was observed
Surtos de vírus Vaccinia-like nos Estados de São Paulo e Goiás, Brasil: detecção, isolamento e identificação viral
Since October 2001, the Adolfo Lutz Institute has been receiving vesicular fluids and scab specimens of patients from Paraíba Valley region in the São Paulo and Minas Gerais States and from São Patricio Valley, in the Goiás State. Epidemiological data suggested that the outbreaks were caused by Cowpox virus or Vaccinia virus. Most of the patients are dairy milkers that had vesiculo-pustular lesions on the hands, arms, forearms, and some of them, on the face. Virus particles with orthopoxvirus morphology were detected by direct electron microscopy (DEM) in samples of 49 (66.21%) patients of a total of 74 analyzed. Viruses were isolated in Vero cell culture and on chorioallantoic membrane (CAM) of embryonated chicken eggs. Among 21 samples submitted to PCR using primers for hemagglutinin (HA) gene, 19 were positive. Restriction digestion with TaqI resulted in four characteristic Vaccinia virus fragments. HA nucleotide sequences showed 99.9% similarity with Cantagalo virus, described as a strain of Vaccinia virus. The only difference observed was the substitution of one nucleotide in the position 616 leading to change in one amino acid of the protein in the position 206. The phylogenetic analysis showed that the isolates clustered together with Cantagalo virus, other Vaccinia strains and Rabbitpox virus.A partir de outubro de 2001, o Instituto Adolfo Lutz tem recebido amostras de líquido vesicular e crostas de lesões de pele de pacientes das regiões do Vale do Paraíba, Estado de São Paulo e do Vale do São Patricio, Estado de Goiás. Os dados clínicos e epidemiológicos sugeriam que os surtos poderiam ser causados por Cowpox virus ou Vaccinia virus. A maioria dos pacientes era ordenhadores que tinham lesões vesicopustulares nas mãos, braços, antebraços e alguns na face. A análise por microscopia eletrônica direta (MED) detectou partículas com morfologia de vírus do gênero Orthopoxvirus em amostras de 49 (66,21%) pacientes dos 74 analisados. Os vírus foram isolados em membrana corioalantóide (MCA) de ovo embrionado de galinha e em linhagem celular Vero com confirmação por MED e PCR. Das 21 amostras de lesões submetidas ao PCR utilizando iniciadores para o gene da hemaglutinina (HA), 19 foram positivas. A digestão por enzima de restrição TaqI resultou em quatro fragmentos característicos de Vaccinia virus. A análise nucleotídica do seqüenciamento revelou que esses vírus apresentam 99,9% de similaridade com o Cantagalo virus, descrito como uma cepa de Vaccinia virus, havendo apenas alteração de um nucleotídeo na posição 616 com mudança de um aminoácido na proteína na posição 206. A análise filogenética mostrou que os isolados se agruparam junto aos Cantagalo virus, outras cepas de Vaccinia virus e Rabbitpox virus
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
O impacto do último enxágue na citotoxicidade de produtos críticos passíveis de processamento
RESUMO Objetivo Avaliar a citotoxicidade de produtos submetidos à contaminação desafio, limpeza baseada em procedimento operacional padrão (POP) validado e enxágue final em diferentes tipos de água: de torneira, deionizada, destilada, tratada por osmose reversa e ultrapurificada. Método Estudo experimental e laboratorial. Foram utilizadas como amostras 130 cânulas de hidrodissecção, 26 por grupo experimental, caracterizados, de acordo com a água utilizada no último enxágue. As amostras foram submetidas à contaminação desafio interna e externamente por uma solução contendo 20% sangue de carneiro desfibrinado e 80% de Cloreto de Sódio a 0,9%. Em seguida, tiveram o lúmen preenchido por solução viscoelástica, permanecendo em contato com o contaminante por 50 minutos, sendo então, processadas, de acordo com um POP validado. A citotoxicidade foi avaliada pela captura do corante vital vermelho neutro. Resultados Ausência de citotoxicidade nos extratos das amostras. Conclusão As amostras não demonstraram citotoxicidade, independentemente da qualidade de água utilizada no último enxágue. Os resultados apresentados puderam ser alcançados unicamente por meio do uso de um procedimento operacional padrão de limpeza validado, baseado em literatura científica, em recomendações oficiais e na legislação relacionada
O impacto do último enxágue na citotoxicidade de produtos críticos passíveis de processamento
RESUMO Objetivo Avaliar a citotoxicidade de produtos submetidos à contaminação desafio, limpeza baseada em procedimento operacional padrão (POP) validado e enxágue final em diferentes tipos de água: de torneira, deionizada, destilada, tratada por osmose reversa e ultrapurificada. Método Estudo experimental e laboratorial. Foram utilizadas como amostras 130 cânulas de hidrodissecção, 26 por grupo experimental, caracterizados, de acordo com a água utilizada no último enxágue. As amostras foram submetidas à contaminação desafio interna e externamente por uma solução contendo 20% sangue de carneiro desfibrinado e 80% de Cloreto de Sódio a 0,9%. Em seguida, tiveram o lúmen preenchido por solução viscoelástica, permanecendo em contato com o contaminante por 50 minutos, sendo então, processadas, de acordo com um POP validado. A citotoxicidade foi avaliada pela captura do corante vital vermelho neutro. Resultados Ausência de citotoxicidade nos extratos das amostras. Conclusão As amostras não demonstraram citotoxicidade, independentemente da qualidade de água utilizada no último enxágue. Os resultados apresentados puderam ser alcançados unicamente por meio do uso de um procedimento operacional padrão de limpeza validado, baseado em literatura científica, em recomendações oficiais e na legislação relacionada