A técnica de coloração AgNOR para regiões organizadoras de nucléolos (NORs) é caracterizada por marcar proteínas ligadas ao ácido ribonucléico ribossômico, avaliando a proliferação celular. O ...objetivo do trabalho foi estudar a morfometria ovariana e a validade da técnica AgNOR na proliferação de células saudáveis das estruturas ovarianas em ovelhas mestiças. Foram colhidos 102 pares de ovários e mensurou-se o diâmetro do maior folículo de cada ovário. Do maior corpo lúteo (CL), o diâmetro e a largura foram mensurados, classificando-os em: incluso, protruso, maciço e cavitário, seguidos por coloração AgNOR. O nível de significância foi de 5% (R Statistical System). Houve diferença (p<0,05) para o diâmetro do maior folículo entre os lados direito (OD): 4,2±2,3mm e esquerdo (OE): 3,6±2,2mm. Houve correlação (p<0,01) entre as NORs da teca interna (TI) e externa (TE): OD (0,46) e OE (0,61); NORs da granulosa e TI: OD (0,54) e OE (0,59); e entre NORs da granulosa e TE: OD (0,34) e OE (0,38). Conclui-se que a quantificação das NORs foi apropriada para o estudo da determinação do potencial de proliferação das estruturas ovarianas, a qual foi similar para os lados direito e esquerdo.
Estimating the size of the coronavirus disease 2019 (COVID-19) pandemic and the infection severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is made challenging by ...inconsistencies in the available data. The number of deaths associated with COVID-19 is often used as a key indicator for the size of the epidemic, but the observed number of deaths represents only a minority of all infections
. In addition, the heterogeneous burdens in nursing homes and the variable reporting of deaths of older individuals can hinder direct comparisons of mortality rates and the underlying levels of transmission across countries
. Here we use age-specific COVID-19-associated death data from 45 countries and the results of 22 seroprevalence studies to investigate the consistency of infection and fatality patterns across multiple countries. We find that the age distribution of deaths in younger age groups (less than 65 years of age) is very consistent across different settings and demonstrate how these data can provide robust estimates of the share of the population that has been infected. We estimate that the infection fatality ratio is lowest among 5-9-year-old children, with a log-linear increase by age among individuals older than 30 years. Population age structures and heterogeneous burdens in nursing homes explain some but not all of the heterogeneity between countries in infection fatality ratios. Among the 45 countries included in our analysis, we estimate that approximately 5% of these populations had been infected by 1 September 2020, and that much higher transmission rates have probably occurred in a number of Latin American countries. This simple modelling framework can help countries to assess the progression of the pandemic and can be applied in any scenario for which reliable age-specific death data are available.
In enteric viral infections, such as those with rotavirus and norovirus, individual viral particles shed in stool are considered the optimal units of fecal-oral transmission. We reveal that ...rotaviruses and noroviruses are also shed in stool as viral clusters enclosed within vesicles that deliver a high inoculum to the receiving host. Cultured cells non-lytically release rotaviruses and noroviruses inside extracellular vesicles. In addition, stools of infected hosts contain norovirus and rotavirus within vesicles of exosomal or plasma membrane origin. These vesicles remain intact during fecal-oral transmission and thereby transport multiple viral particles collectively to the next host, enhancing both the MOI and disease severity. Vesicle-cloaked viruses are non-negligible populations in stool and have a disproportionately larger contribution to infectivity than free viruses. Our findings indicate that vesicle-cloaked viruses are highly virulent units of fecal-oral transmission and highlight a need for antivirals targeting vesicles and virus clustering.
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•Rotaviruses and noroviruses are shed in stool as viral clusters inside vesicles•Vesicles containing virus clusters remain intact during fecal-oral transmission•Vesicles achieve a high MOI and induce severe disease•Vesicle-cloaked viral clusters are more virulent units than free viral particles
Freely disseminating standalone viral particles are considered the optimal agents for spreading infection. Santiana et al. discover that enteric viruses are also shed in feces as viral clusters cloaked in vesicles. These virus-containing vesicles are a more potent infectious form that enhances the MOI and disease severity.
In this paper, the influence of culture conditions (irradiance, temperature, pH, and dissolved oxygen) on the photosynthesis rate of
Scenedesmus almeriensis
cultures is analyzed. Short-run ...experiments were performed to study cell response to variations in culture conditions, which take place in changing environments such as outdoor photobioreactors. Experiments were performed by subjecting diluted samples of cells to different levels of irradiance, temperature, pH, and dissolved oxygen concentration. Results demonstrate the existence of photoinhibition phenomena at irradiances higher than 1,000 μE/m
2
s; in addition to reduced photosynthesis rates at inadequate temperatures or pH—the optimal values being 35 °C and 8, respectively. Moreover, photosynthesis rate reduction at dissolved oxygen concentrations above 20 mg/l is demonstrated. Data have been used to develop an integrated model based on considering the simultaneous influence of irradiance, temperature, pH, and dissolved oxygen. The model fits the experimental results in the range of culture conditions tested, and it was validated using data obtained by the simultaneous variation of two of the modified variables. Furthermore, the model fits experimental results obtained from an outdoor culture of
S. almeriensis
performed in an open raceway reactor. Results demonstrate that photosynthetic efficiency is modified as a function of culture conditions, and can be used to determine the proximity of culture conditions to optimal values. Optimal conditions found (
T
= 35 °C, pH = 8, dissolved oxygen concentration <20 mg/l) allows to maximize the use of light by the cells. The developed model is a powerful tool for the optimal design and management of microalgae-based processes, especially outdoors, where the cultures are subject to daily culture condition variations.
To assess the feasibility of the menstrual cup for short-term management of urinary leakage among women with vesicovaginal fistula (VVF).
A repeated measures design compared volume of leakage with ...and without the cup via a 2-hr pad test among women with VVF seeking surgical repair at a health facility in Ghana. Subsequently a gynecological exam was administered to assess safety outcomes, followed by a questionnaire to assess acceptability and perceived efficacy. A paired t-test was used to analyze reduction of leakage in ml, and percent reduction was reported. Study limitations include observer bias while evaluating adverse outcomes and the possibility of social desirability bias during questionnaire administration that might overestimate the effect of the cup and women's acceptability.
Of the 32 patients screened, 11 were eligible (100% consent rate). At baseline, mean (±SD) leakage in ml was 63.2 (±49.2) (95% CI: 30.2-96.3) over two hours, while the mean leakage over two hours of use of the cup was 16.8 (±16.5) (95% CI: 5.7-27.9). The mean difference of 46.4 (±52.1) ml with use of the cup (95% CI: 11.4-81.4) was statistically significant (p = 0.02). With the cup, women experienced an average 61.0% (±37.4) (95% CI: 35.9-86.2) leakage reduction, a difference 10/11 users (91.0%) perceived in reduced leakage. One participant, reporting four previous surgical attempts, experienced a 78.7% leakage reduction. Acceptability was high-women could easily insert (8/11), remove (8/11), and comfortably wear (11/11) the cup and most (10/11) would recommend it. No adverse effects attributable to the intervention were observed on exam, although some women perceived difficulties with insertion and removal. Data collection tools were appropriate with slight modification advised.
A larger trial is warranted for a more robust evaluation of the menstrual cup for management of urinary leakage due to VVF among women who have not yet accessed surgery or for whom surgery was not successful.
Living with extremely low-income is an important risk factor for HIV/AIDS and can be mitigated by conditional cash transfers. Using a cohort of 22.7 million low-income individuals during 9 years, we ...evaluated the effects of the world's largest conditional cash transfer, the Programa Bolsa Família, on HIV/AIDS-related outcomes. Exposure to Programa Bolsa Família was associated with reduced AIDS incidence by 41% (RR:0.59; 95%CI:0.57-0.61), mortality by 39% (RR:0.61; 95%CI:0.57-0.64), and case fatality rates by 25% (RR:0.75; 95%CI:0.66-0.85) in the cohort, and Programa Bolsa Família effects were considerably stronger among individuals of extremely low-income reduction of 55% for incidence (RR:0.45, 95% CI:0.42-0.47), 54% mortality (RR:0.46, 95% CI:0.42-0.49), and 37% case-fatality (RR:0.63, 95% CI:0.51 -0.76), decreasing gradually until having no effect in individuals with higher incomes. Similar effects were observed on HIV notification. Programa Bolsa Família impact was also stronger among women and adolescents. Several sensitivity and triangulation analyses demonstrated the robustness of the results. Conditional cash transfers can significantly reduce AIDS morbidity and mortality in extremely vulnerable populations and should be considered an essential intervention to achieve AIDS-related sustainable development goals by 2030.
A major mosquito-borne viral disease outbreak caused by Zika virus (ZIKV) occurred in Bahia, Brazil, in 2015, largely due to transmission by the mosquito, Aedes aegypti (L.). Detecting ZIKV in field ...samples of Ae. aegypti has proven problematic in some locations, suggesting other mosquito species might be contributing to the spread of ZIKV. In this study, several (five) adult Aedes albopictus (Skuse) mosquitoes that emerged from a 2015 field collection of eggs from Camaçari, Bahia, Brazil, were positive for ZIKV RNA; however, attempts to isolate live virus were not successful. Results from this study suggest that field-collected Ae. albopictus eggs may contain ZIKV RNA that require further tests for infectious ZIKV. There is a need to investigate the role of Ae. albopictus in the ZIKV infection process in Brazil and to study the potential presence of vertical and sexual transmission of ZIKV in this species.
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