Navegando por Palavras-chave "Bacterial Translocation"

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    Estudo da translocação bacteriana em um modelo experimental de hipertensão porta aguda e crônica
    (Universidade Federal de São Paulo (UNIFESP), 2009-09-30) Toma, Ricardo Katsuya [UNIFESP]; Koh, Ivan Hong Jun [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Portal Hypertension (PH) is a Syndrome that clinically manifests with ascites, portosystemic encephalopathy and esophageal variceal hemorrhage, and is often associated with bacterial infections leading to death. Given the predominance of enteric bacterial origin in these infections, the causal factor has been attributed to the bacterial translocation (BT) phenomena. The aim of this study was to evaluate the role of the acute and chronic portal hypertension (APH and CPH) state on the BT process. Methods: Wistar EPM rats (n=62) were randomly distributed in 3 groups: BT, APH and CPH, with or without BT induction on the post-operative days 2 and 14, by oroduodenal inoculation [10 ml E. Coli R6, 107 or 1010 colony-forming units (CFU/ml)], which were confined in the small bowel for 2 hours period. Control groups (Sham groups) were injected with saline. The PH was induced by calibrated portal vein stenosis. Portal vein flow and spleen weight were monitored. Mesenteric lymph node (MLN), liver, spleen, lung, blood and peritoneal fluid (PF) samples were cultured. Results: When the APH factor was associated to the high inoculum BT induction (1010CFU/mL), both higher positive percentage and bacterial recovery index were seen at the extra-intestinal sites as well as to the lung and peritoneal fluid, sites usually free of BT-event. Besides, usually BT-negative low inoculum (107CFU/mL) was able to provoke translocation. In the CPH period, lower translocation-index was seen as compared to the APH phase with both inoculum. However, the translocation susceptibility to the peritoneal fluid persisted at the CPH period. Conclusion: 1) PH factor modified the intensity, threshold and pattern of bacterial allocation to the extraintestinal compartments under this BT-model. 2) The acute PH state favored BT-process as well as the lung and peritoneal cavity susceptibility to bacterial allocation. 3) The chronic PH state was less susceptible for BT-process as compared to acute PH phase, although, peritoneal cavity susceptibility to bacterial allocation persisted. 4) BT process differences between acute and chronic PH phases seemed to have relation with the time dependent hemodynamic adaptation.
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    Estudo das repercussões intestinais e sistêmicas secundárias à ressecção intestinal em ratos
    (Universidade Federal de São Paulo (UNIFESP), 2020-10-29) Toma, Ricardo Katsuya [UNIFESP]; Koh, Ivan Hong Jun [UNIFESP]; Universidade Federal de São Paulo
    Objective: The aim of this project was to study the intestinal and systemic repercussions secondary to intestinal resection. Method: Wistar-EPM-1 rats were divided into 5 groups: Group eVIC ( n = 5), submitted to ileocecal valve exclusion; Group RÍleo, n = 5), submitted to 50% distal resection of the small intestine and intestinal anastomosis; Group RÍleoeVIC (n = 5), submitted to 50% distal resection of the small intestine and intestinal anastomosis and exclusion of the ileocecal valve, Group RJejuno (n = 5 ), submitted to 50% proximal resection of the small intestine and intestinal anastomosis and; Naive group (n = 5). After 12 weeks, the intestine, liver and kidney microcirculation of the animals were monitored by SDF techniques and tissue perfusion by laser-doppler. Next, samples from the mesentery, liver, lung and intestine lymph nodes were collected for histological and microbiological study. The techniques evaluated the profile of microcirculatory dysfunction and tissue histology to establish the correlation between the findings. The techniques evaluated the profile of microcirculatory and tissue dysfunction to establish the correlation between the findings. Through the recovery of aerobic and / or facultative anaerobic Gram-negative bacteria, the bacterial concentration was monitored in the duodenum, remaining intestine, colon and feces to observe the occurrence of SCBI, and in the lymph node of the mesentery, liver and lung, to evaluate the occurrence of bacterial translocation. Results: Tissue damage was observed in the duodenum, liver, kidney and lungs in all groups that underwent surgical procedures, mainly in the RJejuno group, and less evident in eVIC. SCBI occurred in groups without the ileocecal valve (eVIC and RÍleo-eVIC), but mainly in the RJejuno group. Bacterial translocation occurred only for the mesentery lymph node with a low positivity index. The changes observed occurred in a proceduredependent manner and the changes were more intense after resection of the jejunal segment. Conclusions: The analysis of the results showed that resections of 50% of the small intestine promote lasting local and systemic inflammatory changes, associated with the imbalance of facultative aerobic and anaerobic Gram negative bacteria and microcirculatory dysfunction. In addition, intestinal resections of segments of the small intestine promote different local and systemic tissue repercussions, which were greater in jejunal resection compared to the ileum.