The use of avian animal models has contributed to the understanding of many aspects of the ontogeny of the hematopoietic system in vertebrates. However, specific events that occur in the model itself are still unclear. There is a lack of consensus, among previous studies, about which is the intermediate site responsible for expansion and differentiation of hematopoietic cells, and the liver's contribution to the development of this system. Here we aimed to evaluate the presence of hematopoiesis in the yolk sac and liver in chickens, from the stages of intra-aortic clusters in the aorta-genital ridges-mesonephros (AGM) region until hatching, and how it relates to the establishment of the bone marrow. Gallus gallus domesticus L. embryos and their respective yolk sacs at embryonic day 3 (E3) and up to E21 were collected and processed according to standard histological techniques for paraffin embedding. The slides were stained with hematoxylin-eosin, Lennert's Giemsa, and Sirius Red at pH 10.2, and investigated by light microscopy. This study demonstrated that the yolk sac was a unique hematopoietic site between E4 and E12. Hematopoiesis occurred in the yolk sac and bone marrow between E13 and E20. The liver showed granulocytic differentiation in the connective tissue of portal spaces at E15 and onwards. The yolk sac showed expansion of erythrocytic and granulocytic lineages from E6 to E19, and E7 to E20, respectively. The results suggest that the yolk sac is the major intermediate erythropoietic and granulopoietic site where expansion and differentiation occur during chicken development. The hepatic hematopoiesis is restricted to the portal spaces and represented by the granulocytic lineage.
Stryphnodendron adstringens (Mart.) Coville (barbatimão) is a tree belonging to the Fabaceae family, and it is commonly found in the southeastern Brazilian cerrado. The stem bark of this tree is traditionally used as an anti-inflammatory and antiseptic agent to treat leucorrhea and diarrhea, as well as to promote wound healing (owing to the presence of proanthocyanidins). Proanthocyanidins were obtained from the ethanolic extract of S. adstringens stem bark and assessed by reversed phase-high performance liquid chromatography with an ultraviolet/diode array detector. The identified compounds included gallic acid, catechin, gallocatechin (GC), epigallocatechin, and epigallocatechin gallate (EGCG). The selected markers, GC and EGCG, were simultaneously used for chromatographic validation (linearity range: 30-330 ng, equivalent to 3-33 µg/mL; r>0.998). The method showed precision (intra-day relative standard deviation [RSD]: 1.72% for GC; 1.16% for EGCG; inter-day RSD: 1.74%-2.60% for both markers), accuracy, robustness, and selectivity. The limits of detection and quantitation were 0.29 µg/ml and 0.89 µg/ml for GC, and 0.88 µg/mL and 2.67 µg/mL for EGCG, respectively. In addition, S. obovatum was evaluated and showed an average of 12.2 µg/mL for GC (equivalent to 1.22% w/w) and 14.2 µg/mL for EGCG (equivalent to 1.42% w/w) in the ethanolic extract. The quantitative results were compared to those obtained for S. adstringens, which showed that the markers are present in both species.Uniterms:Stryphnodendron adstringens/phytochemistry. Fabaceae/phytochemistry. Barbatimão/extrato vegetal/evaluation. Proanthocyanidins/evaluation. RP-High performance liquid chromatography/análise quantitativa.Stryphnodendron adstringens (Mart.) Coville (barbatimão) é uma árvore da família Fabaceae encontrada no cerrado do sudeste do Brasil. As cascas do caule das espécies são tradicionalmente utilizadas como agente antiinflamatório e antisséptico para o tratamento de diarreia e leucorreia, bem como para promover a cicatrização de feridas, devido à presença de proantocianidinas. Estas substâncias obtidas a partir do extracto etanólico (EE) de cascas do caule de S. adstringens foram avaliadas por cromatografia líquida de alta eficiência de fase reversa. As substâncias identificadas foram ácido gálico, catequina, galocatequina (GC), epigalocatequina e galato de epigalocatequina (EGCG). Os marcadores selecionados, GC e EGCG, foram utilizados simultaneamente para validação cromatográfica (intervalo de linearidade 30-330 ng, equivalente a 3-33 µg/mL, r>0,998). O método mostrou precisão (intra-dia DPR 1,72% para GC; 1,16% para EGCG; inter-dia DPR 1,74%-2,60% para ambos os marcadores), exatidão, robustez e seletividade. Os limites de detecção e de quantificação de 0,29 µg/mL e 0,89 µg/mL para a GC, e 0,88 ng/mL e 2,67 µg/mL para EGCG, respectivamente. Outra espécie (S. obovatum) avaliada, mostrou valores médios 12,2 µg/mL de GC (equivalente a 1,22% p/p) e 14,2 µg/mL de EGCG (equivalente a 1,42% p/p) encontrados no EE. Os resultados quantitativo...
ABSTRACT:The purpose of this study was to screen the antioxidant activity of medicinal plant extracts from the Brazilian cerrado, through other methods than the total phenolic content and its correlation with the antioxidant activity. Ethanolic extracts of ten species were evaluated through three antioxidant assays, in vitro, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant activity and reducing power; and by using the Folin-Ciocalteu method the total phenolic content was determined. Ethanolic extracts of Stryphnodendron obovatum, Cecropia pachystachya and Duguetia furfuraceae showed strong antioxidant activity (IC 50 <5 µg mL -1 ) in the DPPH free radical scavenging assay; the species Vernonia phosphorea, Hymenaea stignocarpa and Jacaranda ulei may also be highlighted. These results were confirmed in the assays of total antioxidant capacity and reducing power. The extracts of S. obovatum and V. phosphorea showed an abundant phenolic content; therefore, the phenolic content may play a role in the antioxidant activity. These two species, traditionally used in Brazil, showed great power in these assay systems and may be a promising source for the development of natural antioxidants and future candidates for phytochemical and pharmacological studies in related diseases. Keywords
Trata-se de pesquisa documental-descritiva, com abordagem quantitativa que objetivou caracterizar o perfil das pessoas que tentaram suicídio, atendidas no Hospital de Emergência e Trauma em João Pessoa/PB. A amostra constituiu-se de 87 boletins de entrada e prontuários de pacientes com diagnóstico de tentativa de suicídio, entre janeiro a dezembro de 2005. Utilizou-se um formulário contendo informações referentes à idade, sexo e métodos usados para a tentativa do suicídio. Evidenciou-se que a faixa etária mais atingida foi entre 15 a 34 anos (66,6%) para ambos os sexos. As mulheres corresponderam a 53% e os homens representaram 47% dos casos. Os métodos mais utilizados para os homens foram: envenenamento (21,4%), arma branca (19%), ingestão medicamentosa (19%), salto/pulo (14,3%) e automutilação (9,5%). Para as mulheres ingestão medicamentosa (52,1%), envenenamento (37%) e salto/pulo (4,3%). Ressalta-se a necessidade de detectar o nível de periculosidade da intenção suicida e identificar os comportamentos de risco, com vistas a adotar medidas preventivas para novas tentativas.
The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system.
Yellow fever continues to be an important epidemiological problem in Africa and South America even though the disease can be controlled by vaccination. The vaccine has been produced since 1937 and is based on YFV 17DD chicken embryo infection. However, little is known about the histopathological background of virus infection and replication in this model. Here we show by morphological and molecular methods (brightfield and confocal microscopies, immunofluorescence, nested-PCR and sequencing) the kinetics of YFV 17DD infection in chicken embryos with 9 days of development, encompassing 24 to 96 hours post infection. Our principal findings indicate that the main cells involved in virus production are myoblasts with a mesenchymal shape, which also are the first cells to express virus proteins in Gallus gallus embryos at 48 hours after infection. At 72 hours post infection, we observed an increase of infected cells in embryos. Many sites are thus affected in the infection sequence, especially the skeletal muscle. We were also able to confirm an increase of nervous system infection at 96 hours post infection. Our data contribute to the comprehension of the pathogenesis of YF 17DD virus infection in Gallus gallus embryos.
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