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1.
Damus–Kaye–Stansel procedure is a useful method to relieve the systemic ventricular outflow tract obstruction in functionally univentricular heart. Regurgitation of pulmonary valve and recurrence of systemic ventricular outflow obstruction are the major concerns at the late phase of this procedure. Modification of original Damus–Kaye–Stansel procedure that can prevent the use of prosthetic materials is evaluated. The modified Damus–Kaye–Stansel procedure using aortic flap technique was performed in eight patients with functionally univentricular heart. Patients’ ages ranged from 3 to 28 months (mean 14 months). Follow-up period was 37 months as a mean (9–71 months), and the follow-up was complete. There was no operative mortality and no late death. In addition, there was no recurrence of systemic ventricular outflow tract obstruction throughout the follow-up period. Regurgitation of the pulmonary valve estimated by echocardiography at the latest follow-up was none to trivial in seven patients and mild in one. The modified Damus–Kaye–Stansel procedure using aortic flap technique is a safe, useful and reproducible technique to solve systemic ventricular outflow tract obstruction in functionally univentricular heart, and it can be an alternative for original technique or the so-called double-barrel modification.  相似文献   
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Serum carcinoembryonic antigen (CEA), immunosuppressive acidic protein (IAP) and C-reactive protein (CRP) levels were measured in patients with adult T cell leukemia (ATL) in order to clarify their significance in this disease. Mean (+/- SD) serum CEA levels in 11 patients with acute ATL (3.1 +/- 1.3 ng/ml) and 7 patients with smoldering ATL (3.1 +/- 0.5 ng/ml) were significantly higher than in sera of 222 healthy controls (2.4 +/- 1.3 ng/ml). However, the levels in 7 patients with chronic ATL and healthy controls showed no differences. On the other hand, mean (+/- SD) serum IAP levels in patients with acute ATL (928 +/- 395 micrograms/ml), chronic ATL (487 +/- 125 micrograms/ml) and smoldering ATL (429 +/- 90 micrograms/ml) were significantly higher than in sera of healthy controls (359 +/- 103 micrograms/ml). However, the levels in patients with smoldering ATL and healthy controls showed no differences. Serum IAP levels in crisis in chronic and smoldering ATL were similar to those in patients with acute ATL. 85% of ATL patients with IAP levels above 500 micrograms/ml had CRP levels above 1+. Serum CEA, IAP and CRP levels were serially measured in a number of patients. Serum IAP and CRP levels reflected each patient's clinical course more than serum CEA levels. Overall the simultaneous measurements of serum CEA, IAP and CRP levels revealed a potential usefulness for determination of ATL subtype, and serum IAP and CRP levels may provide a way to evaluate the effectiveness of chemotherapy.  相似文献   
3.
Insulin hypersensitivity in mice lacking the V1b vasopressin receptor   总被引:1,自引:0,他引:1  
We have reported that [Arg8]-vasopressin-stimulated insulin release is blunted in islet cells isolated from V1b receptor-deficient ( V1bR −/−) mice. In this study, we used V1bR −/− mice to examine the physiological role of the V1b receptor in regulating blood glucose levels in vivo , and we found that the fasting plasma glucose, insulin and glucagon levels were lower in V1bR −/− mice than in wild-type ( V1bR +/+) mice. Next, we evaluated glucose tolerance by performing an intraperitoneal glucose tolerance test (GTT). The plasma glucose and insulin levels during the GTT were lower in V1bR −/− mice than in V1bR +/+ mice. An insulin tolerance test (ITT) revealed that, after insulin administration, plasma glucose levels were lower in V1bR −/− mice than in V1bR +/+ mice. In addition, a hyperinsulinaemic–euglycaemic clamp study showed that the glucose infusion rate was increased in V1bR −/− mice, indicating that insulin sensitivity was enhanced at the in vivo level in V1bR −/− mice. Furthermore, we found that the V1b receptor was expressed in white adipose tissue and that insulin-stimulated phosphorylation of Akt as an important signaling molecule was increased in adipocytes isolated from V1bR −/− mice. Thus, the blockade of the V1b receptor could result, at least in part, in enhanced insulin sensitivity by altering insulin signalling in adipocytes.  相似文献   
4.
The present study includes a histopathological and immunohistochemical study of 4 cases of diffuse hyperplasia of gastric argyrophil cells. The mode of proliferation of these cells and the production of hormone by these cells have been documented. The distribution of microacinar nests composed of argyrophil cells was thought to be related to chronic gastritis in which there are atrophy of mucosa and intestinal metaplasia. In the case in which these nests were found only in the corpus ventriculi, there was intestinal metaplasia throughout the stomach. On the other hand, in the case in which these nests appeared only in the pyloric area, atrophy of the mucosa with mild intestinal metaplasia was observed only in the pyloric area. The microacinar nests composed of argyrophil cells were distributed in the deep mucosa at the basal portion of the glands in the area with intestinal metaplasia. Serial sections revealed a sprout composed of argyrophil cells budding from the gland with intestinal metaplastic changes. The sprout buds out from the growth zone of glands with Intestinal metaplasia and then becomes isolated and gives rise to reactive hyperplasia. The peptide hormone contained in these cells differs according to the mucosal environments. Cells containing gastrin were observed in the pyloric area, but not in the corpus ventriculi where there was marked intestinal metaplasia. The cells in this area were assumed to contain other hormones.  相似文献   
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Bacteria produce many types of hemolysin that induce diarrhea by mechanisms that are not completely understood. Aeromonas sobria hemolysin (ASH) is a major virulence factor produced by A. sobria, a human pathogen that causes diarrhea. Since epithelial cells in the intestine are the primary targets of hemolysin, we investigated the effects of ASH on ion transport in human colonic epithelial (Caco-2) cells. ASH increased short-circuit currents (Isc) in a dose-dependent manner, and it also activated a 125I efflux from Caco-2 cells. ASH-induced Isc increases and 125I efflux activations were both suppressed by low Ca2+ levels in the extracellular solution or by pretreatment with the Ca2+ chlelator BAPTA-AM. Intracellular Ca2+ levels were increased by ASH in a biphasic fashion characterized by a rapid sharp increase (peak 1) followed by a sustained low plateau (peak 2). ASH-induced peak 1 was inhibited by pretreatment with pertussis toxin, indicating that Ca2+ was mobilized from intracellular stores, and peak 2 was induced by an influx of extracellular Ca2+. Peak 2 but not peak 1 was related to Cl- secretion. These results indicate that ASH activates Ca2+-dependent Cl- secretion.  相似文献   
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The structural organization and 5'-flanking region of the mouse V1a and V1b vasopressin receptor genes were determined. The mouse V1a receptor gene was located within an 8-kb XbaI fragment, and the mouse V1b receptor gene was located within a 14-kb EcoRV fragment. Both genes were comprised of two coding exons that were separated by a 2.3-kb and a 8.0-kb intron, respectively, located before the respective seventh transmembrane domain of the receptor sequence. The availability of these genes would allow us to study the functional role of V1a and V1b receptors by disrupting the gene in mice.  相似文献   
10.
Prolidase deficiency is an autosomal recessive disorder with highly variable symptoms, including mental retardation, skin lesions, and abnormalities of collagenous tissues. In Japanese female siblings with polypeptide negative prolidase deficiency, and with different degrees of severity of skin lesions, we noted an abnormal mRNA with skipping of 192 bp sequence corresponding to exon 14 in lymphoblastoid cells taken from these patients. Transfection and expression analyses using the mutant prolidase cDNA revealed that a mutant protein translated from the abnormal mRNA had an Mr of 49,000 and was enzymatically inactive. A 774-bp deletion, including exon 14 was noted in the prolidase gene. The deletion had termini within short, direct repeats ranging in size of 7 bp (CCACCCT). The "slipped mispairing" mechanism may predominate in the generation of the deletion at this locus. This mutation caused a 192-bp in-frame deletion of prolidase mRNA and was inherited from the consanguineous parents. The same mutation caused a different degree of clinical phenotype of prolidase deficiency in this family, therefore factor(s) not related to the PEPD gene product also contribute to development of the clinical symptoms. Identification of mutations in the PEPD gene from subjects with prolidase deficiency provides further insight into the physiological role and structure-function relationship of this biologically important enzyme.  相似文献   
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