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991.
Advanced glycation end (AGE)-products, a complex and heterogeneous group of compounds, have been implicated in diabetes-related long-term complications. Up to the present, only few data exist about serum levels of the AGE-proteins N- epsilon -carboxymethyllysine (CML) and pentosidine in selection-free populations of patients with type 1 and insulin-treated type 2 diabetes mellitus. In the present 10-year, population-based trial of patients with insulin-treated diabetes mellitus, serum CML and pentosidine levels were examined in correlation to the patients' quality of diabetes control and the prevalence of diabetes-related long-term complications. Jena's St. Vincent Trial (JEVIN) was started in 1989/1990. At this time, a centralised diabetes care system existed. After the baseline examination of 190 patients (83% of the target population) with insulin-treated diabetes mellitus, follow-up examinations were performed in 1994/1995 and 1999/2000. In 1994/1995, the CML concentration in patients with type 1/type 2 diabetes mellitus was 1096.47+/-405.50/1136.43+/-405.24 ng/ml. In 1999/2000, it was significantly lower (727.49+/-342.91 ng/ml, P=.033/743.76+/-312.47 ng/ml, P<.0001). The same tendency showed the AGE-protein pentosidine (type 1: 1994/1995 203.18+/-118.88 vs. 1999/2000 156.59+/-104.84 pmol/ml [P=.029], type 2: 1994/1995 189.72+/-67.66 vs. 1999/2000 151.54+/-127.73 pmol/ml [P=.020]). Parallel to the decrease in the mean concentration of the AGE-products CML and pentosidine mean HbA1c improved and the prevalence of diabetic long-term complications (retino-, neuro-, and nephropathy) remained comparable 1999/2000-1989/1990. Comparing the data of 1999/2000 with those from 1994/1995, there was not only a substantial improvement in patients' quality of diabetes control but also a decrease in the concentration of AGE-products. In patients with diabetes mellitus, the AGE-products seem to be mainly influenced by the quality of diabetes control. However, the most important parameter reflecting the risk for development and progression of diabetes-related long-term complications seems not to be the AGE-products, but patients' HbA1c.  相似文献   
992.
OBJECTIVE: To evaluate the relationship between the cerebral tissue oxygenation index measured by near-infrared spectroscopy and central venous oxygen saturation (SvO2) after corrective surgery of congenital heart defects in children. DESIGN: Prospective observational clinical study. SETTING: A tertiary neonatal and paediatric intensive care unit for paediatric cardiology. PATIENTS: Neonates and children consecutively admitted to the paediatric cardiology intensive care unit after corrective surgery of non-cyanotic congenital heart defects. MEASUREMENTS AND RESULTS: Forty-three children were studied. Cerebral tissue oxygenation index, measured non-invasively by near-infrared spectroscopy, was compared to SvO2, measured by a catheter placed in the right atrium, and to haemodynamic and respiratory parameters. Pearson's correlation coefficients and p values were calculated. Simultaneously measured values for SvO2 (62.2+/-9.8%, 39.8-80.4%) and cerebral tissue oxygenation index (56.7+/-8.8%, 35.8-71.2%) showed a significant correlation ( r=0.52, p<0.001). CONCLUSION: Cerebral tissue oxygenation index and SvO2 are not interchangeable parameters, but cerebral tissue oxygenation index reflects the haemodynamic influence on cerebral oxygenation after cardiovascular surgery. Further work is necessary to confirm the clinical role of continuous non-invasive measurement of cerebral tissue oxygenation index with regard to the variations of global systemic oxygen consumption after cardiac surgery in children.  相似文献   
993.
994.
Objective Intrathecal bolus administration of nitric oxide donors and calcium channel antagonists has been proposed to reduce cerebral vasospasm (CVS) in animal subarachnoid hemorrhage (SAH) models. Intrathecal continuous administration of these substances for CVS prevention has not been extensively evaluated. This study compared the efficacy of continuous intrathecal infusions of the NO donor glyceroltrinitrate and nimodipine in preventing delayed CVS associated with SAH in an animal model in vivo. Methods New Zealand White rabbits were randomly assigned to six groups: no SAH/NaCl, no SAH/NO, no SAH/nimodipine, SAH/NaCl, SAH/NO, or SAH/nimodipine. Glyceroltrinitrate (GTN) at 0.5 μg/μl (0.5 μl/h) or nimodipine at 0.2 μg/μl (10 μl/h) or NaCl was continuously infused into the cisterna magna via an Alzet osmotic pump from day 0 to day 5 after injection of 1.0 ml autologous blood. The magnitude of spasm in the basilar artery was determined by comparison of pre- and posttreatment angiography and was calculated as proportional change in intraluminal diameter based on automatic measurements. Results A total of 55 experiments and 110 angiograms were performed. SAH was associated with vasoconstriction of the basilar artery (SAH/NaCl group 19.85 ± 2.94%). Continuous intrathecal injection of GTN and nimodipine prevented SAH-induced CVS. There was significant prevention of CVS in animals treated with GTN (SAH/NO group 5.93 ± 5.2%, n = 11) and nimodipine (SAH/nimodipine group: 0.55 ± 2.66%, n = 9). There was no significant difference between the treatment groups and controls in prevention of CVS. Conclusions This study demonstrates that prophylactic continuous intrathecal administration of either GTN or nimodipine equally prevents SAH-associated CVS in an animal model. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. This study was supported by the Cerebrovascular Research Fund from the Departments of Neurosurgery and Intensive Care Medicine (account no. 34-160), University of Berne, Switzerland.  相似文献   
995.
AIM: To investigate the c-kit expression in biliary tract cancer cell lines and histological sections from patients with extrahepatic cholangiocarcinoma (CC) and to evaluate the efficacy of in vitro and in vitro treatment with imatinib mesilate. METHODS: The protein expression of c-kit in the human biliary tract cancer cell lines Mz-ChA-2 and EGI-1 and histological sections from 19 patients with extrahepatic CC was assessed by immunoblotting, immunocytochemistry, and immunohistochemistry. The anti-proliferative effect of imatinib mesilate on biliary tract cancer cell lines Mz-ChA-2 and EGI-1 was studied in vitro by automated cell counting. In addition, immunodeficient NMRI mice (TaconicTM) were subcutaneously injected with 5×106 cells of cell lines MzChA-2 and EGI-1. After having reached a tumour volume of 200 mm3, daily treatment was started intra peritonea I ly with imatinib mesilate at a dose of 50 mg/kg or normal saline (NS). Tumor volume was calculated with a Vernier caliper. After 14 d, mice were sacrificed with tumors excised and tumor mass determined. RESULTS: Immunoblotting revealed presence of c-kit in Mz-ChA-2 and absence in EGI-1 cells. Immunocytochemistry with c-kit antibodies displayed a cytoplasmatic and membraneous localization of receptor protein in Mz-ChA-2 cells and absence of c-kit in EGI-1 cells, c-kit was expressed in 7 of 19 (37%) extrahepatic human CC tissue samples, 2 showed a moderate and 5 a rather weak immunostaining. Imatinib mesilate at a low concentration of 5μmol/L caused a significant growth inhibition in the c-kit positive cell line Mz-ChA-2 (31%), but not in the c-kit negative cell line EGI-1 (0%) (P<0.05). Imatinib mesilate at an intermediate concentration of 10μmol/L inhibited cellular growth of both cell lines (51% vs 57%). Imatinib mesilate at a higher concentration of 20μmol/L seemed to have a general toxic effect on both cell lines. The IC50 values were 9.7μmol/L and 11μmol/L, respectively. After 14 d of in vitro treatment with imatinib mesilate, using the chimeric mouse model, c-kit positive Mz-ChA-2 tumors had a significantly reduced volume and mass as compared to NS treatment (P< 0.05). In contrast to that, treatment of mice bearing c-kit negative EGI-1 tumors did not result in any change of tumor volume and mass as compared to NS treatment. CONCLUSION: c-kit expression is detectable at a moderate to low protein level in biliary tract cancer. Imatinib mesilate exerts marked effects on tumor growth in vitro and in vitro dependent on the level of c-kit expression.  相似文献   
996.
997.

Background

The pathogenesis of diverticular disease (DD) is considered to be multifactorial and involves intestinal motor disturbances and an underlying enteric neuromuscular pathology. While an enteric neuropathy has been well documented, actual studies on concomitant alterations of the enteric musculature are limited. This study is aimed at reassessing the smooth muscle tissue by histological, ultrastructural and molecular-biological approaches.

Methods

Full-thickness sigmoid specimens were obtained from patients with DD (n = 20) and controls (n = 19). Morphometric analysis was performed to evaluate the thickness and connective tissue index of the circular and longitudinal muscle layers as well as the myenteric plexus. Structural alterations were determined by light and transmission electron microscopy. mRNA profiles of components of the contractile smooth muscle apparatus including smooth muscle α-actin, smoothelin, histone deacetylase 8, and smooth muscle myosin heavy chain (SMMHC) were assessed by qPCR. Altered gene expression levels were confirmed at protein level by immunohistochemistry.

Results

Compared to controls, patients with DD showed (1) increased thickness of the circular and longitudinal muscle layers, (2) architectural alterations of smooth muscle cells, (3) increased connective tissue index of the longitudinal muscle layer, (4) focally reduced density of myofilaments at ultrastructural level, (5) specific down-regulation of SMMHC mRNA levels, (6) decreased immunoreactivity of SMMHC, (7) oligo-neuronal hypoganglionosis.

Conclusions

DD is associated with distinct structural and functional alterations of the enteric musculature. The enteric myopathy is characterized by disturbed muscular architecture, connective tissue replacement and loss of specific myofilaments and thus may contribute to the pathogenesis and progression of DD.  相似文献   
998.
Hemobilia is a rare cause of acute upper gastrointestinal bleeding and is often associated with a history of hepatic or biliary tract injury, tumor growth, hepatic artery aneurysm, cholecystitis, or hepatic abscess. We report a case of a 76-year-old patient with massive hemobilia due to intrahepatic bleeding from the segment 8 hepatic artery without evidence of a true aneurysm, abscess, or metastatic disease 4 weeks following pylorus-preserving total pancreatectomy for pancreatic cancer. Gastroduodenoscopy suggested hemorrhage from the duodenojejunostomy but failed to achieve hemostasis, and the patient underwent exploratory laparotomy. It was realized intraoperatively that the bleeding originated from the intrahepatic biliary tract. Bleeding was controlled by blocking the right hepatic bile duct with a Fogarty catheter and subsequent transarterial embolization. Computed tomography did not reveal any local liver or vascular pathology. Retrospectively, the cause of delayed profuse hemobilia was most likely a traumatic intrahepatic pseudoaneurysm following endoscopic bile duct stenting 3 weeks before the pancreatectomy. The reported case is exceptional and of particular interest because of the absence of a typical history or cause of hemobilia, preoperative misleading diagnostic results in an altered anatomic situation, and the operative management to achieve bleeding control in this emergency setting.  相似文献   
999.
OBJECTIVE: Hyperandrogenism is a central feature of the polycystic ovary syndrome (PCOS) and might worsen insulin resistance (IR) often seen in PCOS. Androgens act through the androgen receptor (AR). A polymorphic CAG repeat sequence within the AR gene was reported to modulate its transactivation activity. Therefore, we investigated a putative interaction between testosterone and the CAG repeat length polymorphism with respect to IR. DESIGN: In 63 PCOS women with normal glucose tolerance free testosterone, the biallelic CAG repeat length and a multiplicative interaction term were investigated by multiple linear regression analysis for an association with IR as indicated by the homeostasis model assessment of IR (HOMA-IR). RESULTS: Free testosterone was correlated with HOMA-IR. The impact of testosterone on HOMA-IR was modified by the AR CAG length as indicated by an interaction term. This interaction remained significant after adjustment for smoking, age and body mass index. While there was a positive association of free testosterone with HOMA-IR, the interaction term was inversely associated. The model, which explained 42.5% of the variation of HOMA-IR predicted that in carriers of short CAG lengths, an increase in testosterone increased IR. This effect attenuated with rising biallelic CAG length until it turns into the opposite at a CAG length longer than 23. The results were confirmed by using CIGMA as another measure of IR. CONCLUSIONS: The association between testosterone and IR is modified by the CAG repeat polymorphism within the AR. Therefore, the evaluation of testosterone effects on IR seems to require consideration of the AR CAG repeat polymorphism in PCOS women.  相似文献   
1000.
PURPOSE: To evaluate the short-term outcome of patients who underwent carotid stenting with the routine use of cerebral protection devices. METHODS: In five centers, 808 successful stent procedures (of 815 attempted) were performed in 753 patients (557 [74%] men; mean [+/- SD] age, 70 +/- 8 years). Cerebral protection involved distal filter devices (n=640), occlusive distal balloons (n=144), or proximal balloon protection (n=24). RESULTS: The protection device was positioned successfully in 793 (98.2%) of the 808 attempted vessels. Neurologic complications occurred within 30 days after 46 procedures (5.6%), including seven major strokes, 17 minor strokes, and 22 transient ischemic attacks. There were four deaths (one following a major stroke). The 30-day incidence of stroke and death was 3.3% (27/815). The rate of stroke or death was 3.8% (8/213) for symptomatic lesions and 3.2% (19/602) for asymptomatic lesions (P=0.87), and 3.4% (25/729) in patients aged <80 years and 2% (2/86) in those aged > or =80 years (P=0.81). Protection device-related vascular complications, none of which led to neurologic symptoms, occurred after nine procedures (1.1%). CONCLUSION: In this uncontrolled study, routine cerebral protection during carotid artery stenting was technically feasible and clinically safe. The incidence of major neurologic complications in this study was lower than in previous reports of carotid artery stenting without cerebral protection.  相似文献   
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