[Prognostic factors of mortality in the malignant biliary obstruction unresectable after the insertion of an endoscopic stent]. / Factores pronósticos de mortalidad en la estenosis biliar distal maligna irresecable después de la colocación de una prótesis endoscópica.

OBJECTIVE: To determine the factors prognostics of early mortality in the malignant billary estenosis after the endoscopic derivation. BACKGROUND DATA: The surgical, percutaneous or endoscopic derivation is the alternative of palliative treatment in the biliary obstruction unresectable. The factors prognostic the early mortality after surgical derivation are: hemoglobin < 10 g/dL, serum bilirubin > 10 mg/dL and serum albumin < 2.5 g/dL; for the percutaneous derivation they are the sanguineous urea more of 4.3 mmol/L and hemoglobin < 10.9 g/dL; whereas in the single endoscopic derivation type 3 of Bismuth and the infectious complications after the endoscopic colangiography and the absence of the clinical success were factors prognoses of early mortality. METHODS: Descriptive and retrospective analysis of 97 cases with malignant biliary obstruction. The factors were evaluated prognoses of early mortality. Univariated and bivaried analysis and of survival by the method of Kaplan-Meier was made curved. RESULTS: 97 cases were included that presented/displayed unresectable disease and had a biochemical control subsequent to the drainage. They were 58 women and 39 men. More frequent symptoms: ictericia, pain and prurito. 61 cases of distal obstruction and 36 with proximal obstruction. Twenty deaths (25.9%) happened within the 30 later days to the treatment. The bilirubin > 14 mg/dL and the proximal location were like predicting of early mortality. CONCLUSIONS: The obstruction biliary more frequent is located in choledocho distal and is of pancreatic origin. The main factors associated to early mortality are: the bilirubin > of 14 mg/dL and the proximal location reason why is important the suitable selection of patient candidates to endoscopic derivation. The survival is better in the distal obstruction.

Effects of high-salt diet on CYP450-4A omega-hydroxylase expression and active tone in mesenteric resistance arteries.

This study investigated the role of changes in the expression of the cytochrome P-450 4A (CYP450-4A) enzymes that produce 20-hydroxyeicosatetraenoic acid (20-HETE) in modulating the responses of rat mesenteric resistance arteries to norepinephrine (NE) and reduced Po(2) after short-term (3-day) changes in dietary salt intake. The CYP450-4A2, -4A3, and -4A8 isoforms were all detected by RT-PCR in arteries obtained from rats fed a high-salt (HS, 4% NaCl) diet, whereas only the CYP450-4A3 isoform was detected in vessels from rats fed a low-salt (LS, 0.4% NaCl) diet. Expression of the 51-kDa CYP450-4A protein was significantly increased by a HS diet. Inhibiting 20-HETE synthesis with 30 muM N-methylsulfonyl-12,12-dibromododec-11-enamide (DDMS) reduced the vasoconstrictor response to NE in arteries obtained from rats fed either a LS or HS diet, but NE sensitivity after DDMS treatment was significantly lower in vessels from rats on a HS diet. DDMS treatment also restored the vasodilator response to reduced Po(2) that was impaired in arteries from rats on a HS diet. These findings suggest that 1) a HS diet increases the expression of CYP450-4A enzymes in the mesenteric vasculature, 2) 20-HETE contributes to the vasoconstrictor response to NE in mesenteric resistance arteries, 3) the contribution of 20-HETE to the vasoconstrictor response to NE is greater in rats fed a HS diet than in rats fed a LS diet, and 4) upregulation of the production of 20-HETE contributes to the impaired dilation of mesenteric resistance arteries in response to hypoxia in rats fed a HS diet.

Expression of cytochrome P450-4A isoforms in the rat cremaster muscle microcirculation.

OBJECTIVE: This study sought to identify any specific cytochrome P450 (CYP450) -4A enzyme isoforms expressed in arterioles and/or the surrounding parenchymal tissue of the rat cremaster muscle. METHODS: RT-PCR was used to detect the presence of specific CYP450-4A isoforms in isolated muscle fibers and arterioles from the cremaster muscle of Sprague-Dawley rats; CYP450-4A protein expression was determined by Western blotting. RESULTS: CYP450-4A3 mRNA was expressed in isolated muscle fibers and in cremasteric arterioles, while CYP450-4A8 mRNA was expressed only in cremasteric arterioles. CYP450-4A1 and CYP450-4A2 mRNA were not expressed in arterioles and skeletal muscle cells, although all four isoforms were strongly expressed in the liver. CYP450-4A protein was detected in both the isolated muscle fibers and in the isolated arterioles. CONCLUSIONS: The present study identifies the specific pattern of cytochrome P450-4A isoform expression in arterioles and parenchymal cells of the skeletal muscle microcirculation, and supports the hypothesis that the cytochrome P-450 enzymes may play a role in the regulation of microvascular function in the skeletal muscle microcirculation.