Avaliação bioquímica da isquemia cerebral focal, não associada à reperfusão, por oclusão da artéria cerebral média em ratos

Cerebral ischemia is an important event in clinical and surgical neurological practice since it is one of the diseases that most compromise the human species. In the present study 40 adult rats were submitted to periods of focal ischemia of 30, 60 and 90 min without reperfusion and animals submitted to a sham procedure were used as controls. We analyzed the levels of ATP, malondialdehyde and caspase-3. No significant differences in the biochemical measurements were observed between the right and left brain hemispheres of the same animal in each experimental group. Reduced ATP levels were observed after the three periods of ischemia compared to the sham group. No significant increase in malondialdehyde or caspase-3 levels was observed. Despite significant changes in ATP levels, the results indicated cell viability in the ischemic region as shown by the low rates of lipid peroxidation and apoptosis, findings probably related to the lack of reperfusion.Isquemia cerebral é um acontecimento importante na prática neurológica clínica e cirúrgica, uma vez que é uma das doenças que mais comprometem a espécie humana. No presente estudo 40 ratos adultos foram submetidos a períodos de isquemia focal de 30, 60 e 90 min e como controle foram utilizados animais do grupo sham. Foram analisados os níveis de ATP, malondialdeído e caspase-3. Nenhuma diferença significativa nas dosagens bioquímicas foram observadas entre os hemisférios cerebrais direito e esquerdo do mesmo animal em cada grupo experimental. Foi observada redução nos níveis de ATP após os três períodos de isquemia, em comparação com o grupo sham. Nenhum aumento significativo dos níveis de malondialdeído ou caspase-3 foi observado. Apesar das alterações significativas nos níveis ATP, os resultados indicaram viabilidade celular na região isquêmica como demonstrado pela baixa taxa de peroxidação lipídica e apoptose, achados que provavelmente estão relacionados com a falta de reperfusão

Expressão da apoptose em enxertos de veias safenas humana para restauração do fluxo sanguíneo coronariano por derivação

OBJECTIVE: To investigate the possible role of apoptosis on brief distensions of human saphenous veins at different pressures. METHODS: Fresh isolated grafts of human saphenous vein were assigned as control or distended (D) for fifteen seconds at 100, 200 and 300 mmHg. The degree of apoptotic caspases 3, 8, 9 and anti-apoptotic protein Bcl-2 expression were assessed by immunohistochemistry. RESULTS: Fresh isolated segments of distended human saphenous veins presented similar apoptotic protein expression when compared with control veins. However, the Bcl-2 expression was significantly higher in the 300 mmHg distended segments compared with the control vein. CONCLUSION: These findings show that intact segments of human saphenous veins submitted to distensions at different pressures have similar apoptotic proteins expression when compared with non-distended control veins. Therefore, brief distensions commonly performed during surgical harvesting do not trigger apoptosis, and probably are not involved on the physiopathological mechanisms that lead to graft failureOBJETIVO: Investigar o possível papel da apoptose em distensões breves de veias safenas humanas em diferentes pressões. MÉTODOS: Segmentos frescos isolados de veia safena humana foram distribuídos em 4 grupos: controle ou distendidos (D) por quinze segundos a 100, 200 e 300 mmHg. O grau de apoptose das caspases 3, 8, 9 e expressão da proteína anti-apoptótica Bcl-2 foram avaliados por imuno-histoquímica. RESULTADOS: Segmentos frescos distendidos isolados de veias safenas humanas apresentaram expressão protéica para apoptose similar às veias controle. No entanto, a expressão de Bcl-2 foi significativamente maior nos segmentos distendidos a 300 mmHg, quando comparados à veia controle. CONCLUSÃO: Estes achados demonstram que segmentos intactos de veias safenas humanas submetidos a distensões em diferentes pressões têm expressão de proteínas apoptóticas similares quando comparados com veias controle nãodistendidas. Por conseguinte, breves distensões comumente realizadas durante a coleta cirúrgica não ativam o processo de apoptose e, provavelmente, não estão envolvidas em mecanismos fisiopatológicos que levam à falência do enxertoFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)(FAEPA) Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (USP) - Fundação de Apoio ao Ensino, Pesquisa e Assistência do Hospital das Clínica

Morphological examination of the epididymal duct in the dog

The epithelium lining of the epididymal duct is pseudostratified columnar and the cell population is comprised of principal, basal, and apical cells. The stroma periductal, is a well developed framework surrounding the tubule. Epididymal epithelial heights were maximal in the initial segment and minimal in the tail. Luminal diameter was just the reverse of the last pattern, e.g., it increased along the length of the duct.O ducto epididimário, no cão, acha-se revestido por epitélio colunar pseudoestratificado, com população celular constituída por células principais, basais e apicais, presentes em todas as regiões. Este epitélio é circundado pelo estroma peritubular. O epitélio do segmento inicial epididimário possui a maior altura, que diminui progressivamente em direção à cauda epididimária. Ocorre um aumento progressivo do lúmen tubular através das diferentes regiões, sendo maior na região da cauda epididimária, configurando um local de estocagem de espermatozóides

Expressão de caspase-3 e Bcl-2 em glioblastomas: um estudo imunohistoquímico

The unfavorable prognosis of malignant gliomas can also be explained by the incomplete knowledge of their molecular pathways. Studies regarding the regulatory process of apoptosis in glioblastoma (GBM), the most common malignant glioma, are few, and better knowledge of the expression of pro and anti-apoptotic proteins could collaborate with the development of new treatments founded on molecular basis. The objective of this study was to evaluate by immunohistochemistry the expression of caspase-3 and Bcl-2 in 30 samples of GBMs. The expression of caspase-3 (mean 17.67%) was lower than Bcl-2 (mean 30.92%), a statistically significant result (p<0.0001), suggesting low apoptotic activity in these tumors. Other studies of proteins related to the intrinsic and extrinsic pathway of apoptosis are required to provide additional information of this mechanism in GBMs.O prognóstico desfavorável dos gliomas malignos também pode ser explicado pelo pouco conhecimento dos seus mecanismos moleculares. Estudos relacionados à regulação do processo de apoptose em glioblastoma (GBM), o glioma maligno mais comum, são poucos, e o melhor conhecimento da expressão de proteínas pró e anti-apoptóticas poderia colaborar com o desenvolvimento de novos tratamentos fundamentados sobre a base molecular. O objetivo deste estudo foi avaliar por imunohistoquímica, a expressão de caspase-3 e Bcl-2 em 30 amostras de GBM. A expressão de caspase-3 (média de 17,67%) foi menor que a de Bcl-2 (média de 30,92%), com resultado estatisticamente significante (p<0.0001), sugerindo menor atividade apoptótica nestes tumores. Outros estudos envolvendo proteínas relacionadas à via extrínseca e intrínseca da apoptose são necessários para fornecer informações complementares deste mecanismo em GBMs

Molecular Profiling Reveals Biologically Discrete Subsets and Pathways of Progression in Diffuse Glioma

Therapy development for adult diffuse glioma is hindered by incomplete knowledge of somatic glioma driving alterations and suboptimal disease classification. We defined the complete set of genes associated with 1,122 diffuse grade II-III-IV gliomas from The Cancer Genome Atlas and used molecular profiles to improve disease classification, identify molecular correlations, and provide insights into the progression from low- to high-grade disease. Whole-genome sequencing data analysis determined that ATRX but not TERT promoter mutations are associated with increased telomere length. Recent advances in glioma classification based on IDH mutation and 1p/19q co-deletion status were recapitulated through analysis of DNA methylation profiles, which identified clinically relevant molecular subsets. A subtype of IDH mutant glioma was associated with DNA demethylation and poor outcome; a group of IDH-wild-type diffuse glioma showed molecular similarity to pilocytic astrocytoma and relatively favorable survival. Understanding of cohesive disease groups may aid improved clinical outcomes

Integrated genomic characterization of oesophageal carcinoma

Oesophageal cancers are prominent worldwide; however, there are few targeted therapies and survival rates for these cancers remain dismal. Here we performed a comprehensive molecular analysis of 164 carcinomas of the oesophagus derived from Western and Eastern populations. Beyond known histopathological and epidemiologic distinctions, molecular features differentiated oesophageal squamous cell carcinomas from oesophageal adenocarcinomas. Oesophageal squamous cell carcinomas resembled squamous carcinomas of other organs more than they did oesophageal adenocarcinomas. Our analyses identified three molecular subclasses of oesophageal squamous cell carcinomas, but none showed evidence for an aetiological role of human papillomavirus. Squamous cell carcinomas showed frequent genomic amplifications of CCND1 and SOX2 and/or TP63, whereas ERBB2, VEGFA and GATA4 and GATA6 were more commonly amplified in adenocarcinomas. Oesophageal adenocarcinomas strongly resembled the chromosomally unstable variant of gastric adenocarcinoma, suggesting that these cancers could be considered a single disease entity. However, some molecular features, including DNA hypermethylation, occurred disproportionally in oesophageal adenocarcinomas. These data provide a framework to facilitate more rational categorization of these tumours and a foundation for new therapies

Integrated genomic characterization of pancreatic ductal adenocarcinoma

We performed integrated genomic, transcriptomic, and proteomic profiling of 150 pancreatic ductal adenocarcinoma (PDAC) specimens, including samples with characteristic low neoplastic cellularity. Deep whole-exome sequencing revealed recurrent somatic mutations in KRAS, TP53, CDKN2A, SMAD4, RNF43, ARID1A, TGFβR2, GNAS, RREB1, and PBRM1. KRAS wild-type tumors harbored alterations in other oncogenic drivers, including GNAS, BRAF, CTNNB1, and additional RAS pathway genes. A subset of tumors harbored multiple KRAS mutations, with some showing evidence of biallelic mutations. Protein profiling identified a favorable prognosis subset with low epithelial-mesenchymal transition and high MTOR pathway scores. Associations of non-coding RNAs with tumor-specific mRNA subtypes were also identified. Our integrated multi-platform analysis reveals a complex molecular landscape of PDAC and provides a roadmap for precision medicine