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61.
Ohta M  Ikeda M  Togo T  Suzuki S 《Microsurgery》2006,26(2):87-92
Soft-tissue reconstruction of the feet in diabetic patients with angiopathy, sensorial neuropathy, and immunopathy is a complicated problem. Until the mid-1980s, chronic foot ulcers in diabetic patients were treated conservatively, because flap surgery was regarded as too risky. However, in recent years, early debridement and flap coverage have become popular reconstructive methods for diabetic foot wounds. Several flap donor sites are available, depending on the nature of the defect. The deep inferior epigastric artery perforator (DIEP) flap is a relatively new flap that developed as a modification of the transverse rectus abdominis muscle (TRAM) flap. It provides a large amount of skin and subcutaneous tissue, without the donor-site morbidity of the ordinary TRAM flap. Furthermore, using the DIEP flap avoids the loss of major vessels. In this study, we report on the successful use of the DIEP flap in four cases of diabetic foot ulceration.  相似文献   
62.

Purpose

The aim of this study is to investigate the surgical outcomes of surgery for non-small cell lung cancer (NSCLC) in patients with coronary artery disease (CAD).

Methods

Among 805 patients who underwent surgery for NSCLC at our hospital within a recent 10-year period, 43 (5.3 %) had a history of CAD. We analyzed the surgical outcomes and risk factors for postoperative complications in these 43 patients.

Results

The postoperative mortality and morbidity rates were 2 and 42 %, respectively. The morbidity rate was significantly higher in the patients with CAD than in those without CAD (P < 0.01). Postoperative cerebrovascular or cardiovascular events occurred in four patients (9 %). Having two of the following was significantly associated with the development of postoperative complications: decreased cardiac function, respiratory dysfunction, or deteriorated renal function (p = 0.04). The 5-year overall and disease-free survival rates of the patients with CAD were 75.6 and 64.5 %, respectively; comparable with those of the patients without CAD; at 77.9 % and 72.5 %, respectively (p = 0.46 and 0.69).

Conclusions

Patients with NSCLC and a history of CAD are at higher risk of complications after pulmonary resection. Combined decreased organ function is a risk factor for postoperative complications. CAD did not influence the long-term outcomes of patients after pulmonary resection for NSCLC.
  相似文献   
63.
64.
BACKGROUND: A human thymoma is a thymic epithelial neoplasm and is characterized by its frequent association with myasthenia gravis. The histological characteristic of thymoma is coexistence of a large number of lymphocytes, including CD4(+)CD8(+) double positive T cells, phenotypes of the cortical thymocytes. To elucidate the role of these T lymphocytes in the pathogenesis of thymoma-associated myasthenia gravis, we examined the usage of alphabeta or gammadelta T cell receptor of the T lymphocytes in thymoma in conjunction with the positive selection event. MATERIALS AND METHODS: Thymomas were obtained from 28 patients. Nine patients were associated with myasthenia gravis. Lymphocytes were freshly isolated from the tumor tissue and were subjected to four-color flow cytometric analysis. RESULTS: The average proportion of TCRalphabeta(+) cells in thymomas associated with myasthenia gravis was 47.0% and was significantly higher (P = 0.0008) than that without myasthenia gravis (23.4%). Positive selection event was then examined in terms of CD69, a positive selection marker. The mean proportion of TCRalphabeta(+)CD69(+)CD4(+)CD8(-) cells in the myasthenic thymomas (8.22%) was significantly greater (P = 0.015) than the nonmyasthenic thymomas (2.99%). On the other hand, there was not a significant difference in the mean proportion of TCRalphabeta(+)CD69(+)CD4(-)CD8(+) cells between the myasthenic and the nonmyasthenic thymomas. CONCLUSIONS: The possible role of development of TCRalphabeta(+) T cells, especially the role of positive selection of TCRalphabeta(+)CD4(+)CD8(-) T cells in thymoma, was suggested in the pathogenesis of thymoma-associated myasthenia gravis.  相似文献   
65.
Lin CW  Yan F  Shimamura S  Barg S  Shyng SL 《Diabetes》2005,54(10):2852-2858
ATP-sensitive K(+) channels (K(ATP) channels) of pancreatic beta-cells play key roles in glucose-stimulated insulin secretion by linking metabolic signals to cell excitability. Membrane phosphoinositides, in particular phosphatidylinositol 4,5-bisphosphates (PIP(2)), stimulate K(ATP) channels and decrease channel sensitivity to ATP inhibition; as such, they have been postulated as critical regulators of K(ATP) channels and hence of insulin secretion in beta-cells. Here, we tested this hypothesis by manipulating the interactions between K(ATP) channels and membrane phospholipids in a beta-cell line, INS-1, and assessing how the manipulations affect membrane excitability and insulin secretion. We demonstrate that disruption of channel interactions with PIP(2) by overexpressing PIP(2)-insensitive channel subunits leads to membrane depolarization and elevated basal level insulin secretion at low glucose concentrations. By contrast, facilitation of channel interactions with PIP(2) by upregulating PIP(2) levels via overexpression of a lipid kinase, phosphatidylinositol 4-phosphate 5 kinase, decreases the ATP sensitivity of endogenous K(ATP) channels by approximately 26-fold and renders INS-1 cells hyperpolarized, unable to secrete insulin properly in the face of high glucose. Our results establish an important role of the interaction between membrane phosphoinositides and K(ATP) channels in regulating insulin secretion.  相似文献   
66.
We report an 18-month-old boy with the association of pectus excavatum and tetralogy of Fallot (TOF). We successfully performed simultaneous pectus repair using sternal elevation without any prosthetic support and total correction of TOF after a prior modified Blalock-Taussig shunt. Retracting a divided costo-sternal complex with a rectus abdominal flap away from the operative field before the cardiac operation provided excellent surgical exposure. The modified Blalock-Taussig shunt prior to the combined repair prevented life-threatening hypoxic spells during dissection of the deformed sternum and costochondral cartilages before institution of cardiopulmonary bypass.  相似文献   
67.
A 46-year-old man with anomalous origin of the left coronary artery from the pulmonary artery (Bland-White-Garland syndrome) is reported. We successfully performed coronary artery bypass grafting with the use of bilateral internal thoracic arteries and ligation of the anomalous left coronary artery. The patient was discharged from the hospital after an uneventful postoperative course and postoperative coronary angiography, which revealed patent internal thoracic arteries and no leakage of blood flow from the anomalous left coronary artery to the pulmonary artery. This surgical procedure is technically simple and useful for adult patients with Bland-White-Garland syndrome. To our knowledge, this is one of only a few reports on coronary artery bypass grafting with bilateral internal thoracic arteries as a treatment of Bland-White-Garland syndrome.  相似文献   
68.
BACKGROUND: Plasma adrenomedullin (AM) reflects cardiac dysfunction and predicts survival after myocardial infarction. The present study was designed to investigate whether the mature AM (mAM) reflects status of cardiac function, systemic blood volume, or inflammation in hemodialysis patients with cardiovascular disease, and whether mortality and additional cardiovascular morbidity can be predicted by mAM. METHODS: Plasma levels of mAM, atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), norepinephrine (NE), and C-reactive protein (CRP) before hemodialysis were measured in 67 chronic hemodialysis patients with cardiovascular disease, along with 2-dimensional and Doppler echocardiographic variables. RESULTS: By univariate regression analysis, mAM correlated negatively with pulmonary venous flow velocity ratio and left ventricular (LV) ejection fraction and positively with LV inflow velocity ratio, LV end-diastolic, end-systolic volume indexes, plasma CRP level, and removal fluid volume by ultrafiltration. Multivariate stepwise regression analysis revealed that mAM reflected all variables better than log [ANP], log [BNP], and log [NE]. During a 1-year follow-up period, 7 patients died and 8 had additional cardiovascular events. Event-free Kaplan-Meier curves based on the median mAM (4.55 pmol/L) showed that patients with high plasma mAM levels had higher mortality and morbidity than those with low plasma mAM levels (P = 0.0056). By Cox multivariate proportional hazard analysis, mAM was related to mortality and morbidity [hazard ratio (HR) 4.55, 95% CI 1.2-16.8, P= 0.023). CONCLUSION: Plasma mAM reflects cardiac dysfunction, excessive blood volume, and inflammation better than ANP, BNP, and NE, resulting in a predictor of mortality and cardiovascular morbidity in hemodialysis patients with cardiovascular disease.  相似文献   
69.
Studies were conducted to explore altered substrate utilization and metabolism in GLUT4 null mice. Liver fatty acid synthase mRNA and fatty acid synthesis rates were dramatically increased in GLUT4 null mice compared with control mice and were supported by increased rates of the pentose phosphate pathway oxidative phase and sterol regulatory binding protein mRNA expression. Increased GLUT2 protein content, glucokinase mRNA, and glucose-6-phosphate in GLUT4 null mice may provide substrate for the enhanced fatty acid synthesis. Increased fatty acid synthesis, however, did not lead to hepatic triglyceride accumulation in GLUT4 null mice because of increased hepatic triglyceride secretion rates. GLUT4 null mice rapidly cleared orally administered olive oil, had reduced serum triglyceride concentrations in the fed and the fasted state, and increased skeletal muscle lipoprotein lipase when compared with controls. Oleate oxidation rates were increased in GLUT4 null skeletal muscle in association with mitochondrial hyperplasia/hypertrophy. This study demonstrated that GLUT4 null mice had increased hepatic glucose uptake and conversion into triglyceride for subsequent use by muscle. The ability of GLUT4 null mice to alter hepatic carbohydrate and lipid metabolism to provide proper nutrients for peripheral tissues may explain (in part) their ability to resist diabetes when fed a normal diet.  相似文献   
70.
A 70-year-old man was transferred to our hospital with severe congestive heart failure and ventricular arrhythmia due to acute myocardial infarction. He had experienced chest pain 3 weeks previously and was admitted to another hospital for dyspnea, where he required assist ventilation, 1 week prior to the transfer. An echocardiogram revealed a broad anteroseptal infarction and very poor left ventricular function with an ejection fraction (EF) of 22%. He remained in a severe congestive heart failure condition despite a full administration of catecholamines. Coronary angiogram findings revealed an occlusion of the proximal left anterior descending coronary artery and 1 week later severe hypotension was suddenly presented. An echocardiogram showed pericardial effusion with signs of cardiac tamponade. A pericardiocentesis was performed and hemodynamic improvement was obtained for a short time, after which the patient underwent urgent open heart surgery. During the operation, exclusion of the anteroseptal akinetic area using an oval patch was performed under a cardiopulmonary bypass and ventricular fibrillation. Severe cardiac failure remained postoperatively and the patient could not be weaned from cardiopulmonary bypass, therefore, we implanted a percutaneous cardiopulmonary support (PCPS) and started intraaortic balloon pumping (IABP). The patient was weaned from PCPS at 26 days after surgery and from IABP at 30 days. Following hospital release, he has continued to do well without heart failure for 39 months after the operation.  相似文献   
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