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81.
The present study employed enzyme-immunoassay to examine the effect of ethanol on endothelin-1 and/or -2(ET1 + 2) release from human umbilical vein endothelial cells. Thirty minutes of exposure to ethanol increased the release of immunoreactive ET1 + 2 from cultured endothelial cells in a dose-dependent manner. However, ethanol at concentrations of less than 400 mM did not induce any LDH release from the endothelial cells. Trypan blue exclusion test revealed that 400 mM solution of ethanol decreased the cell viability to 7.7%. Thus, ethanol was found to directly stimulate ET1 + 2 release from cultured human umbilical vein endothelial cells. This reaction of vascular endothelial cells against ethanol may be related to ethanol-induced cardiovascular diseases such as hypertension, myocardial infarction and stroke, as well as fatal alcohol syndrome.  相似文献   
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84.
The vascular type of Ehlers-Danlos syndrome (vEDS) is an autosomal dominant hereditary disease characterized by connective tissue fragility throughout the body, including the arteries, viscera, and gastrointestinal tract. We report a case in which we performed transvenous embolization (TVE) via direct superior ophthalmic vein (SOV) approach to treat a direct carotid-cavernous fistula (CCF) in a patient with Ehlers-Danlos syndrome (EDS). The patient was a 37-year-old woman who developed tinnitus in her left ear and a headache during examination in the outpatient clinic of another hospital in order to make a definitive diagnosis of vEDS, and she was referred to our hospital and examined. Based on the results of all of the studies she was diagnosed with a CCF. Conservative treatment was attempted, but was not very effective. Because of progressing aphasia, TVE was performed via the SOV direct cut. There were no intraoperative or postoperative complications. It has been reported that cerebral angiography is generally contraindicated in vEDS and that the morbimortality associated with endovascular treatment is very high. When performing treatment it is necessary to be sufficiently aware of the risks it entails.  相似文献   
85.
Phlebosclerotic colitis is a rare and recently known disease entity and its etiology is still to be elucidated. Some phlebosclerotic colitis cases are difficult to distinguish from collagenous colitis because of the similarity of pathological findings. In all Japanese case reports of phlebosclerotic colitis in which an association with the use of Chinese herbal medicine is suspected, sansisi (gardenia fruit) was included, suggesting pathogenesis of this disease. We report a case of phlebosclerotic colitis that wasdifficult to be distinguished from collagenous colitis, and an association with the use of Chinese herbal medicine was suspected as the cause of the disease.  相似文献   
86.
Aim: Endoscopic screening and removal of colorectal adenomas can reduce the incidence of colorectal cancer. However, given the possibility of adenoma recurrence, surveillance colonoscopy is currently recommended after the initial screening and removal of colorectal adenomas. Aberrant crypt foci (ACF) have been shown to serve as a reliable surrogate marker of colorectal carcinogenesis. In this study, the relationship between the number of ACF at the initial endoscopic polypectomy and the likelihood of colorectal adenoma recurrence after polypectomy were investigated. Methods: High‐magnification chromoscopic colonoscopy was performed in 82 subjects who underwent endoscopic polypectomy to identify ACF in the lower rectum. Surveillance colonoscopy was then performed 3 years after the baseline polypectomy at Yokohama City University Hospital. Results: The number of ACF was greater in patients who showed adenoma recurrence (7.88 ± 6.35) than in those who did not (2.19 ± 2.95) (P < 0.001). Receiver–operating curve analysis showed that the number of ACF was a highly specific predictor of the risk of adenoma recurrence. Conclusions: This is the first study conducted to investigate the relationship between the number of ACF after endoscopic polypectomy and the likelihood of recurrence of colorectal adenomas. These results suggest that the number of ACF is a useful predictor of the likelihood of colorectal adenoma recurrence.  相似文献   
87.
Growth hormone (GH) is known to have a pivotal role in the maintenance of skeletal muscle mass. Sarcopenia, the loss of skeletal muscle mass, is a common phenomenon in aging, and it is widely accepted that sarcopenia is largely attributed to age-related decline in GH secretion. In the present study, we tested if human growth hormone transgenic rats (GH-TG rats) whose plasma GH levels are maintained relatively low could be an appropriate model for sarcopenia. Analyses of GH-TG rats revealed that they exhibit skeletal muscle growth defect as well as atrophy of myofibers. The number of myofibers in tibialis anterior muscle was comparable to that of WT rats, while the proportion of type I slow myofibers in tibialis anterior muscle was increased in GH-TG rats after 5 months. Neither increased expression of ubiquitin ligases, MuRF1 and MAFbx, nor indication of apoptotic cell death was observed. Notably, myogenic differentiation potential of skeletal muscle progenitor cells in GH-TG rats was lower than WT rats, and this was accompanied by increased adipogenic potential. These results indicate that GH-TG rats could be a useful model to elucidate the mechanism of sarcopenia induced by reduced GH action and raised the possibility that decreased GH action may cause an alteration of differentiation potential of skeletal muscle progenitor cells.  相似文献   
88.
We report a 64-year-old woman with follicular thyroid cancer found by subacute bulbar palsy. Progressive bulbar palsy (PBP) was considered the most likely diagnosis, because no abnormal finding was detected on brain CT and blood test except for the decrease of free T4. An echogram of the thyroid revealed a small nodule which was shown to be class IIb by fine needle biopsy. However, 201Tl scintillation examination showed skull base metastasis. Follicular thyroid cancer sometimes seems to manifest as a distant metastasis with no clinically evident thyroid lesion. This case suggested the importance of a detailed survey for malignancy, when subacute bulbar palsy is seen.  相似文献   
89.
Differences in atherosclerotic profiles between patients with thoracic aortic aneurysm (TAA) and patients with abdominal aortic aneurysm (AAA) have not been studied. We retrospectively studied the clinical records of 343 consecutive patients (132 TAA and 211 AAA) who were admitted to our hospital for elective repair of aortic aneurysms between July 2001 and December 2004. Clinical variables were compared between patients with TAA and those with AAA by using a univariate analysis, and those achieving statistical significance were subsequently assessed in a multivariate analysis. The incidence of coronary artery disease (CAD) (53% vs 23%, p <0.0001), 3-vessel coronary disease (41% vs 10%, p <0.0001), male gender (86% vs 74%, p <0.01), smoker (88% vs 76%, p <0.01), chronic obstructive pulmonary disease (COPD) (30% vs 15%, p <0.01), and diabetes mellitus (39% vs 23%, p <0.01) were significantly higher in patients with AAA than in those with TAA. In contrast, the incidence of hypertension (91% vs 81%, p <0.05), saccular-type aneurysm (61% vs 7%, p <0.0001), and body mass index (24.1 +/- 3.1 vs 23.2 +/- 3.5, p <0.05) were significantly higher in patients with TAA than in those with AAA. Multivariate stepwise logistic analysis revealed that CAD (odds ratio [OR] 3.65; 95% confidence interval [CI] 2.12 to 6.42; p <0.0001), COPD (OR 2.05; 95% CI 1.11 to 3.89; p <0.05), and diabetes mellitus (OR 1.85; 95% CI 1.06 to 3.27; p <0.05) were associated with AAA, and that body mass index (OR 9.39; 95% CI 2.0 to 46.8; p <0.01), hypertension (OR 3.09; 95% CI 1.48 to 6.87; p <0.01), and cerebral infarction (OR 2.83; 95% CI 1.25 to 6.50; p <0.05) were associated with TAA. In conclusion, atherosclerotic profiles are significantly different between patients with TAA and patients with AAA. This result suggests the possibility that mechanisms underlying the development of aortic aneurysms may differ between TAA and AAA, and, from the perspective of prevention, provides further stimulus for the modification of key risk factors for atherosclerosis.  相似文献   
90.
The effect on GH secretion of GH-releasing factor (GRF), a 44-amino acid peptide recently isolated from a human pancreatic tumor (hpGRF), was examined in conscious male rabbits. During a 6-h period (1030-1630 h) of the control study individual rabbits exhibited pulsatile GH release with a surge at 1030-1200 h, a trough at 1200-1400 h, and a second peak at 1400-1630 h. Intravenous bolus injections of 1 and 10 micrograms hpGRF caused significant and dose-related increases in plasma GH during both the period of the trough (1300 h) and the surge (1530 h), although the GH responses were obviously higher during the latter than the former period. Passive immunization with anti-somatostatin (SRIF) sheep serum resulted in a prompt increase in plasma GH immediately after an injection of the antiserum. When 0.1, 1, and 10 micrograms hpGRF were successively injected iv at 1215, 1345, and 1515 h, respectively, maximum levels of plasma GH after hpGRF in anti-SRIF sheep serum-treated rabbits were significantly higher than in animals given normal sheep serum. The plasma GH responses to 10 micrograms hpGRF, given iv only once at 1515 h in normal sheep serum-treated animals, were not different from those to 10 micrograms hpGRF injected at 1515 h after the prior administration either of the smaller hpGRF dose (0.1 micrograms, 1215 h; 1 microgram, 1345 h), nor of the large dose (10 micrograms, 1100 h). These findings suggest the following: 1) that the secretion of GH is pulsatile in conscious, unrestrained male rabbits; 2) that hpGRF is a potent secretagogue for GH release in rabbits as well as other species; 3) that the magnitude of plasma GH response to hpGRF is different according to timing of the injection during the course of pulsatile GH secretion but is not influenced by the prior administration of hpGRF (no priming effect); and 4) that the responsiveness of plasma GH to hpGRF is affected by circulating endogenous SRIF.  相似文献   
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