Ciência médica e poliomielite no Brasil na primeira metade do século XX

O artigo analisa os dilemas da ciência médica diante da ameaça da poliomielite até a década de 1950, quando a bacteriologia elaborou um novo modelo e uma vacina eficaz para a doença. Argumenta que, como o modelo proposto por Simon Flexner na década de 1910, apresentava muitas fragilidades, médicos e autoridades sanitárias noBrasil recorriam a modelos diversos para explicar a doença e responder à ansiedade coletiva, especialmente em momentos epidêmicos

Reduced occurrence of programmed cell death and gliosis in the retinas of juvenile rabbits after short-term treatment with intravitreous bevacizumab

OBJECTIVE: Bevacizumab has been widely used as a vascular endothelial growth factor antagonist in the treatment of retinal vasoproliferative disorders in adults and, more recently, in infants with retinopathy of prematurity. Recently, it has been proposed that vascular endothelial growth factor acts as a protective factor for neurons and glial cells, particularly in developing nervous tissue. The purpose of this study was to investigate the effects of bevacizumab on the developing retinas of juvenile rabbits. METHODS: Juvenile rabbits received bevacizumab intravitreously in one eye; the other eye acted as an untreated control. Slit-lamp and fundoscopic examinations were performed both prior to and seven days after treatment. At the same time, retina samples were analyzed using immunohistochemistry to detect autophagy and apoptosis as well as proliferation and glial reactivity. Morphometric analyses were performed, and the data were analyzed using the Mann-Whitney U test. RESULTS: No clinical abnormalities were observed in either treated or untreated eyes. However, immunohistochemical analyses revealed a reduction in the occurrence of programmed cell death and increases in both proliferation and reactivity in the bevacizumab-treated group compared with the untreated group. CONCLUSIONS: Bevacizumab appears to alter programmed cell death patterns and promote gliosis in the developing retinas of rabbits; therefore, it should be used with caution in developing eye

Insight into organoselenium compounds as photosynthesis inhibitors / Investigação dos compostos de organosselênio como inibidores da fotossíntese

The post-emergent herbicidal activities of diphenyl diselenide (A1) and 1,2-bis(4-chlorophenyl)diselenide (A2) were evaluated against Senna obtusifolia and Ipomoea grandifolia plants. On the S. obtusifolia experiment, compound A1 showed the best activity at 100 µM, increasing basic fluorescence parameters F0, F0/FM and FJ by 36%, 30% and 58%, respectively, indicating the reduction of energy transfer from the antenna complex to the reaction centers. Additionally, compound A1 reduced the plant vitality index parameters PIabs, PI(CSm), PSI0 and PHI(E0) by 49%, 45%, 24% and 18%, respectively, suggesting that the redox reactions of the electron transport chain through QA- were interrupted, indicating that compound A1 directly interfered on the PSII electron transport. On the I. grandifolia experiment, compound A2 showed the best result at 200 µM, increasing the parameter F0/FM 21% and reducing the parameters FV, FJ and FI by 14, 9% and 16%, respectively, compared to control. Compound A2 also reduced the parameters ABS/CSM, TR0/CSM and ET0/CSM by 19%, 24% and 25%, respectively, indicating a decrease in the absorbed and trapped energy on the active reaction centers in the cross section. Furthermore, the best result on phytotoxicity experiment was achieved for compound A2 in I. grandifolia weed at 100 µM and 200 µM, reducing the root length by 49% and 32%, respectively. Compound A1 reduced the shoot length by 21% at 200 µM of S. obtusifolia weed. These phytotoxic results corroborate the PSII inhibitory activities demonstrated by the Chl a fluorescence assay, indicating that A1 and A2 have a selective action as a post-emergent herbicide

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Aspectos anatomopatológicos do paciente portador de Pneumonia: Anatomopathological aspects of the patient with Pneumonia

A pneumonia condiz a uma condensação inflamatória aguda dos alvéolos e/ou infiltração tecidual intersticial pulmonar que resulta da ação de células inflamatórias em resposta a injúrias de um determinado agente microbiano. A patologia conforme o local de aquisição, o padrão de comprometimento, o agente etiológico são determinantes para o quadro clínico, lesões e achados radiográficos. O seguinte artigo objetivou descrever através da revisão bibliográfica, os aspectos gerais da pneumonia com foco em abordar os aspectos anatomopatológicos desta enfermidade. Trata-se  de  um  estudo qualitativo  de  revisão  narrativa,  elaborado  para  abordar  sobre os aspectos anatomopatológicos do paciente portador de pneumonia.  É composta por uma análise ampla da literatura, e com uma metodologia rigorosa e replicável ao nível de reprodução de dados e questões quantitativas para resoluções específicas.  Conforme as informações disponíveis na literatura, elucida-se que os pulmões contam com um aparato de mecanismos de defesa. Mas, mediante injúrias e agentes agressores geram um desequilíbrios e posteriormente originam condições que favorecem doenças respiratórias. A pneumonia possui vários agentes etiológicos, e de acordo com este, distintos padrões de acometimento pulmonar e achados radiográficos irão se manifestar