Conditional genome engineering reveals canonical and divergent roles for the Hus1 component of the 9-1-1 complex in the maintenance of the plastic genome of Leishmania.

Leishmania species are protozoan parasites whose remarkably plastic genome limits the establishment of effective genetic manipulation and leishmaniasis treatment. The strategies used by Leishmania to maintain its genome while allowing variability are not fully understood. Here, we used DiCre-mediated conditional gene deletion to show that HUS1, a component of the 9-1-1 (RAD9- RAD1-HUS1) complex, is essential and is required for a G2/M checkpoint. By analyzing genome wide instability in HUS1 ablated cells, HUS1 is shown to have a conserved role, by which it preserves genome stability, and also a divergent role, by which it promotes genome variability. These roles of HUS1 are related to distinct patterns of formation and resolution of single-stranded DNA and γH2A, throughout the cell cycle. Our findings suggest that Leishmania 9-1-1 subunits have evolved to co-opt canonical genomic maintenance and genomic variation functions. Hence, this study reveals a pivotal function of HUS1 in balancing genome stability and transmission in Leishmania. These findings may be relevant to understanding the evolution of genome maintenance and plasticity in other pathogens and eukaryote

Aspectos anatomopatológicos das neoplasias malignas renais: Anatomopathological aspects of malignant renal neoplasms

As neoplasias renais correspondem ao crescimento exacerbado de células tumorais no interior dos rins, classificadas como benignas ou malignas. Neste estudo será abordado sobre as neoplasias malignas renais, a qual correspondem a maior prevalência e são representadas pelo carcinoma de células renais e o tumor de Wilms, com a finalidade de descrever a respeito dos aspectos anatomopatológicos, disseminando informações para o diagnóstico e manejo precoce. O carcinoma de células renais é mais prevalente no sexo masculino, indivíduos mais velhos, geralmente assintomático, contribuindo para o diagnóstico tardio junto a existência de metástases e terapêutica irresponsiva. Não se trata de uma doença genética, sendo o caráter esporádico o predominante, neste contexto os fatores de risco, sobretudo o tabagismo em seguida de obesidade hemodiálise e doenças genéticas são potenciais desencadeantes da enfermidade. Os exames complementares associado a clínica, junto ao acompanhamento eleva a possibilidade de identificação antes de avanços metastáticos. O tumor de Wilms é típico de crianças, acometendo um ou ambos os rins, normalmente com alguma anomalia genética, sendo os sinais inespecíficos, mas sempre manifestando massa palpável e dor abdominal, a qual os métodos de imagem confirmam o diagnóstico e estimam o prognóstico deste. Neste contexto, elucida-se a transcendência que os aspectos anatomopatológicos das neoplasias malignas renais oferecem para a diagnose precoce, devido a escassez e inespecificidafe das manifestações clínicas. Logo, a junção do perfil de cada neoplasia abordado conduz ao manejo adequado e reduz a incidência de tratamentos agressivos e irresponsivos

Estabilidade de ácido ascórbico em sucos de frutas frescos sob diferentes formas de armazenamento

O ácido ascórbico é uma vitamina hidrossolúvel de importância nutricional há muito estabelecida, por sua atuação como cofator em diversos processos fisiológicos e como antioxidante. O ser humano depende da ingestão diária desse micronutriente, cujas principais fontes são as frutas e hortaliças. Por ser um nutriente menos estável, o ácido ascórbico sofre perdas no processamento e no armazenamento, influenciadas por diversos fatores, como pH, temperatura, presença de íons, etc. A literatura apresenta escasso material sobre a estabilidade de ácido ascórbico em armazenamento doméstico, além de haver poucas informações sobre essa vitamina em sucos frescos. A metodologia padrão de análise dessa vitamina em sucos é o Método Titulométrico de Tillmans, que pode apresentar ponto de viragem de difícil visualização. Neste trabalho, foram avaliadas a concentração e a estabilidade do ácido ascórbico de sucos comerciais recém-preparados de laranja, abacaxi com hortelã e melancia, armazenados sob refrigeração e em temperatura ambiente, por dois métodos titulométricos distintos. O método alternativo de análise (NBS) superestimou a concentração de ácido ascórbico das amostras. Não houve diferença significativa na estabilidade da vitamina em sucos armazenados em temperaturas entre 6 e 30ºC, no período testado. O ácido ascórbico foi estável por 24h no suco de laranja, porém apresentou decréscimo significativo após 8h de armazenamento nos sucos de abacaxi e melancia, possivelmente em virtude das diferenças de acidez inicial desses sucos. Em comparação com a literatura disponível, verificou-se que sucos frescos apresentaram menor estabilidade de ácido ascórbico do que sucos industrializados

Comparison of Muscle Strength, Aerobic Capacity and Body Composition between Healthy Adolescents and Those Living with HIV: A Systematic Review and Meta-Analysis

Background: The adverse effects of antiretroviral therapy associated with complications generated by human immunodeficiency virus (HIV) promote impairments in physical fitness in adolescents. Objective: To analyze the aerobic capacity, muscle strength, and body composition of adolescents living with HIV compared with a healthy population of the same age. Methods: Searches were performed in the MEDLINE, Embase, Web of Science, Scopus and SportDiscus databases until September 2019 and updated in April 2020. Eligibility Criteria: adolescents of both sexes in the age group from 10 to 19 years; living with HIV; cross-sectional, case–control, cohort studies; comparing with a healthy population. Mean differences and 95% Confidence intervals (CIs) were calculated using RevMan (software for systematic reviews). Results: Five articles were included, involving 197 adolescents living with HIV (16 to 18 years) and 185 without infection (13 to 18 years), with the sample in each study ranging from 15 to 65 adolescents. Aerobic capacity and muscle strength were reduced in adolescents with HIV, and body mass index was also significantly lower in this group. Conclusion: Adolescents living with HIV have impaired cardiorespiratory fitness, muscle strength, and body composition when compared to their uninfected peers. However, this systematic review provides limited evidence on the differences between the physical fitness outcomes of adolescents living with HIV compared to healthy adolescents

Diminishing benefits of urban living for children and adolescents’ growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified