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31.
Background Autosomal-dominant Alport syndrome is a recognized, but relatively uncommon, form of Alport syndrome. Recently, mutations in theCOL4A3 andCOL4A4 genes, which encode collagen type IV α3 and α4 chains, respectively, have been shown to cause the disease. However, the distribution of α(IV) chains has yet to be determined. Methods To clarify the renal distribution of α(IV) chains, immunohistochemistry of α1(IV) to α6(IV) chains was performed, using chain-specific monoclonal antibodies, raised by us, and an antigen retrieval procedure. Paraffin-embedded renal sections, obtained from 8 patients from 3 families with the disease, were examined. Results The distribution of all 6 α(IV) chains was not significantly different between the 8 patients and the controls. Collagen type IV α1 and α2 chains were ubiquitously expressed, while α3 to α6 chains were detected in the basement membranes of the glomerulus and Bowman's capsule, and/or part of the tubular basement membranes. Conclusions Our findings contrast with those of X-linked and autosomal-recessive Alport syndrome. The distribution pattern of α(IV) chains may provide a useful means of distinguishing the different forms of Alport syndrome.  相似文献   
32.
The distribution of α1–6 chains of type IV collagen (α1–6(IV)) in human fetal kidneys was examined by indirect immunofluorescence. By 11 weeks of gestation, α1, 2, 3, 4, and 6(IV) were already present, but α5(IV) appeared relatively late, at 21 weeks. α1(IV) and α2(IV) were present in all basement membranes, α3(IV) and α4(IV) were restricted to the glomerular basement membrane and parts of the tubular basement membrane. α5(IV) was distributed in the glomerular basement membrane, Bowman’s capsule, and parts of the tubular basement membrane. α6(IV) was present in the Bowman’s capsule, parts of the tubular basement membrane, and occurred in parts of the glomerular basement membrane at the early capillary loop stage, but disappeared during the later capillary loop stage. Received October 23, 1997; received in revised form and accepted February 6, 1998  相似文献   
33.
Whether hemoglobin (Hb) encapsulated liposomes have vasoconstrictive activity remains controversial. We therefore examined the vascular activity of a liposome Hb, Neo red cell (NRC), in a simple in vitro model of Langendorff perfusion of the rat heart using Krebs-Henseleit (KH) solution as the perfusate. In the KH solution, NRC (Hb at 1 mg/ml), however, induced an immediate and abnormal increase in perfusion pressure. Histological examinations revealed that embolisms were the likely cause of this disturbance. Inorganic crystals formed by the mixing of NRC with the perfusate were a possible source of the embolisms. We found that the addition of bovine serum albumin to the perfusate was effective in avoiding embolic events. This protocol was used to compare the vasoconstrictive properties of unmodified bovine Hb and NRC. Unmodified bovine Hb (1 mg/ml) caused an increase in perfusion pressure and a decrease in the duration of bradykinin-induced relaxation. In contrast, NRC (Hb at 1 mg/ml) had no such vasoconstrictive effects. These results provide the first information regarding perfusion of the circulatory vascular bed by NRC and further evidence that the encapsulation of Hb into liposomes is an effective approach to modulate Hb-related vasoconstrictive activity.  相似文献   
34.
OBJECTIVE: The risk of stroke caused by dislodgment of loose atheromatous plaque or mural emboli is increased by cross-clamping of the aorta. Some patients undergo descending thoracic aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. The objective of this study was to determine the influence of proximal aortic cross-clamping in arteriosclerotic aneurysm or dissecting aneurysm repair. METHODS: Between May 1984 and May 2003, 81 patients underwent elective surgery for distal arch or descending aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. To evaluate the influence of the proximal aortic cross-clamping, patients were divided into two groups: patients who had undergone arteriosclerotic aneurysm repair (group I, n=25) and patients who had undergone dissecting aneurysm repair (group II, n=56). RESULTS: Eight (9.9%) of the 81 patients had a stroke. Six strokes occurred in operations for arteriosclerotic aneurysm repair group I and two strokes occurred in operations for dissecting aneurysm repair group II (24 vs 3.6%; p=0.009). In-hospital mortality rates were 12% in group I and 8.9% in group II (p=0.70). Major postoperative complications included renal failure requiring hemodialysis (in 4.2% of the patients in group I and in 8.3% of the patients in group II, p=0.99) and pulmonary complication (in 20% of the patients in group I and in 16% of the patients in group II, p=0.67). CONCLUSION: Cross-clamping between head vessels should be avoided if at all possible when operating on patients who have arteriosclerotic descending thoracic aneurysms.  相似文献   
35.
BACKGROUND: Vascular endothelial growth factor (VEGF), a major angiogenic factor, mediates a variety of disease conditions through promotion of angiogenesis. It also plays a critical role as a potent proinflammatory cytokine in a variety of physiologic and pathologic immune responses. In the present study, we evaluated the expression of VEGF in hepatic warm ischemia-reperfusion (I/R) injury and examined the effect of recombinant human (rh)VEGF administration in an established murine model. METHOD: The expression of VEGF in the liver was assessed by quantitative real-time polymerase chain reaction and immunohistochemistry during I/R injury using 70% partial hepatic ischemia model. The effect of rhVEGF administration on I/R injury was evaluated by measuring liver function and histology. In addition, local inducible nitric oxide synthase (iNOS) and endothelial NO synthase expressions were examined to address the underlying mechanisms. RESULTS: The local expression of VEGF was significantly up-regulated at 2 hours after reperfusion after 60 minutes of ischemia compared with that in the naive liver. VEGF was expressed predominantly in CD11b+ cells infiltrating into the ischemic liver. The administration of rhVEGF had a significant protective effect on ischemic injury in the liver. This effect was associated with the up-regulation of iNOS expression in the rhVEGF-treated liver. CONCLUSION: We demonstrate a dual role of VEGF in hepatic warm I/R injury. Although endogenous VEGF is expressed and functional to initiate hepatic I/R injury, exogenous rhVEGF has a beneficial effect on the ischemic liver. These data may provide new insights into the role of VEGF as well as pathophysiology of hepatic I/R injury.  相似文献   
36.

Purpose

We devised a simple dichotomous classification system and showed sufficient reproducibility to indicate treatment strategies for peritoneal metastasis of colorectal cancer.

Methods

We included 67 patients with peritoneal metastasis of colorectal cancer and classified them according to the largest lesion size, number of lesions and number of regional peritoneal metastases. The oncological data were recorded and compared.

Results

According to the univariate analyses, the prognoses were significantly better in patients with ≤3 disseminated lesions than in those with ≥4, and in patients with disseminated lesions in only one region than in those with ≥2 lesions. A multivariate analysis showed that primary tumor resection and the presence of peritoneal metastases in only one region were favorable factors for the patient survival. Patients with disseminated lesions in only one region (localized group) and those with nonlocalized lesions had three-year survival rates of 45.6 and 12.2 %, respectively. Finally, primary tumor resection improved the prognoses in both the localized and nonlocalized groups.

Conclusions

Colorectal cancer patients were categorized into localized and nonlocalized groups according to the number of regions with peritoneal metastasis, and significant prognostic associations were demonstrated. Subsequent analyses of the oncological data suggested that primary tumor resection contributes to an improved prognosis in all patients with synchronous peritoneal metastases.
  相似文献   
37.
Background  Bile acid has an important role in protecting immune systems related to gut-associated lymphoid tissue. This study was designed to evaluate the effects of internal biliary drainage after a pancreaticoduodenectomy (PD) on postoperative nutrition and complications in a randomized study. Methods  The authors compared the morbidity, mortality, and postoperative nutritional status of 46 patients who had a hepaticojejunostomy (HJ) with a stented external biliary drainage (group E) or with a non-stented internal biliary drainage (group I) after a PD. Results  Systemic infection was recognized in four patients in group E, while no patients in group I. Transthyretin at postoperative 28 days in group I was 15.6 ± 6.2, higher than that in group E. Retinol-binding protein at postoperative 28 days in group I was 2.6 ± 1.0 and also higher than that in group E. Conclusion  HJ with no-stented internal biliary drainage was not associated with systemic infections and mortality, but showed the possibility of improving nutritional status.  相似文献   
38.
Purpose  Restorative proctocolectomy has become the most common surgical option for patients with familial adenomatous polyposis (FAP). However, adenomas may develop in the ileal pouch mucosa over time, and even carcinoma in the pouch has been reported. Our aim was to evaluate the prevalence, nature, and etiology of ileal pouch and nonpouch adenomas and carcinoma in patients with FAP. Patients and methods  This was a retrospective study of 31 FAP patients with Kock’s continent ileostomy (Kock; n = 8), ileorectal anastomosis (IRA; n = 7), and ileal pouch–anal anastomosis (IPAA) (n = 16). All patients were followed with a standardized protocol including chromoendoscopy and biopsies of visible polyps in the ileal pouch and nonpouch mucosa. Results  Sixteen of 24 pouch patients (Kock and IPAA) developed adenomas in the ileal pouch mucosa, and all patients with IRA developed adenomas in the rectal mucosa. The prevalence of ileal adenomas was significantly higher in pouch patients than in IRA patients (P = 0.002). Only one patient with Kock showed adenoma in the prepouch area. Two cases of adenocarcinomas and one case of advanced adenoma were found in the ileal pouch mucosa. Conclusion  Our results show a high frequency of adenomas in the ileal pouch mucosa, with evolution into carcinoma in some patients. Regular endoscopic surveillance of the pouch is recommended at a frequency similar to that for the rectal mucosa after IRA in pouch patients with FAP.  相似文献   
39.
We report a case of bladder hernia. A 68-year-old man was admitted to our hospital for the management of prostate cancer. An egg-sized soft mass was palpated at his right inguinal region. Magnetic resonance imaging and cystography revealed that the mass was a bladder hernia. During radical prostatectomy, we had to resect the bladder hernia for safe regional lymphadenectomy. This hernia was the extraperitoneal type. The stage of prostate cancer was pT3b N0 M0. This is the third reported case of inguinal bladder hernia associated with prostate cancer in Japan.  相似文献   
40.
We report what seems to be the second documented case of perineal hernia after laparoscopic abdominoperineal resection (APR) and describe its successful repair with transperineal intraperitoneal mesh. An 89-year-old woman complained of a large, painful perineal swelling 4 months after APR for rectal cancer. Computed tomography (CT) showed small intestine protruding through the pelvic floor into the perineal area. However, opening of the hernia sac revealed no intra-abdominal adhesions. An oval, 8 × 12 cm Bard Composix Kugel Patch (Davol, Cranston, RI, USA) was inserted into the intraperitoneal space and secured over the defect in the pelvic floor; then firmly attached to the pelvic wall with 16 interrupted nonabsorbable sutures. There has been no sign of hernia recurrence in 10 months of follow-up. We speculate that because laparoscopic surgery is minimally invasive, fewer postoperative adhesions in the abdominal cavity can result in the small bowel sliding more readily into the perineal area. Based on our experience, perineal hernia after laparoscopic APR can be repaired easily and effectively with a Composix Kugel Patch.  相似文献   
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