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971.
972.
973.
974.
Maria T. Rinaudo Magda Curto Ivana Rabbone Marco Piccinini Renato Bruno Silvia Mioletti Silvia Gamba 《Journal of diabetes and its complications》1994,8(4):221-225
In circulating lymphocytes from patients with non-insulin-dependent diabetes mellitus (NIDDM) subnormal pyruvate dehydrogenase (PDH) activity returns to normal following patient treatment with sulfonylurea (gliclazide*, 80 mg twice daily/5 weeks). Moreover, in vitro in cells from diabetic patients exposed to insulin at 50 μU/mL PDH activation also occurs; in cells of controls the same happens for insulin at 5 μU/mL, whereas at 50 μU/mL inhibition takes place. Therefore, the low PDH activity in cells of NIDDM patients might be caused by defective insulin control on the enzyme and its recovery in gliclazide-treated patients by drug-mediated removal of the defect. The validity of the hypothesis was verified in this study where cells of NIDDM patients before and after gliclazide treatment were exposed, in vitro, to insulin at 5 and 50 μU/mL and then tested for PDH activity. In such conditions, the profile of PDH behavior in treated patients was no longer comparable to that in untreated patients but closer to that in euglycemic controls, thus supporting the view that the recovery of PDH activity in NIDDM patients following gliclazide treatment might be the expression of an additional effect that the drug would have in these patients, aimed to renew cell responsiveness to insulin. 相似文献
975.
976.
Differential expression of connective tissue growth factor in inflammatory bowel disease 总被引:2,自引:0,他引:2
di Mola FF Di Sebastiano P Gardini A Innocenti P Zimmermann A Büchler MW Friess H 《Digestion》2004,69(4):245-253
Inflammatory bowel disease consists of Crohn's disease (CD) and ulcerative colitis (UC). A major clinical problem in some patients is to differentiate clearly between these entities, which is important when planning appropriate medical and surgical treatment. Connective tissue growth factor (CTGF), a novel peptide involved in fibrotic disorders, was analyzed in the present study in CD and UC patients to evaluate its possible role in these two disorders. Twenty-five normal human intestinal tissue samples were obtained through an organ donor program. CD tissues were obtained from 28 individuals undergoing partial intestinal resection (17 small bowel; 11 large bowel) due to complications of the disease. UC tissue samples were obtained from 16 patients undergoing colectomy due to complications of the disease. Expression of CTGF was studied by Northern blot analysis. In situ hybridization was used to localize mRNA moieties in the tissue samples. Northern blot analysis revealed an average 5-fold increase in CTGF mRNA expression in 89% (25/28) of CD tissue samples by comparison with normal controls (p < 0.0001). In contrast, in UC samples CTGF mRNA levels were comparable to those of normal controls. However, UC tissue samples exhibited enhanced TGF-beta1 mRNA levels (4-fold; p < 0.05). In situ hybridization in CD samples showed CTGF mRNA localized especially in fibroblasts within the submucosal layer, around lymph follicles and in some areas of intense damage in the proximity of the luminal surface, whereas inflammatory cells were devoid of any CTGF mRNA signal. The present data indicate that CTGF plays a different role in IBD and might be useful, especially in those cases with unusual disease presentation, to better differentiate UC and CD. In addition, our data indicate a crucial role for CTGF in CD, where fibrosis and stenosis are frequent complications that require surgery. 相似文献
977.
Domenico G. Della Rocca MD Michele Magnocavallo MD Veronica N. Natale MPH Carola Gianni MD PhD Sanghamitra Mohanty MD Chintan Trivedi MD MPH Carlo Lavalle MD Giovanni B. Forleo MD PhD Nicola Tarantino MD Jorge Romero MD Xiadong Zhang MD Mohamed Bassiouny MD Amin Al-Ahmad MD David J. Burkhardt MD Joseph G. Gallinghouse MD Javier E. Sanchez MD Rodney P. Horton MD Luigi Di Biase MD PhD Andrea Natale MD 《Journal of cardiovascular electrophysiology》2021,32(9):2441-2450
978.
Paraskevi Petrakopoulou Lydia Anthopoulou Michael Muscholl Volker Klauss Wolfgang von Scheidt Peter Uberfuhr Bruno M Meiser Bruno Reichart Michael Weis 《Journal of the American College of Cardiology》2006,47(8):1622-1629
OBJECTIVES: This study aimed to compare changes in coronary endothelial function, systemic endothelin-1 (ET-1) levels, and vascular remodeling in heart transplant recipients randomized to cyclosporin A (CyA) or tacrolimus (Tac) immunosuppression. BACKGROUND: Functional endothelial abnormalities and intimal thickening are sensitive measures of early cardiac allograft vasculopathy (CAV). METHODS: The randomized, prospective study was performed in two groups of 22 patients, maintained on Tac or CyA and mycophenolate mofetil immunosuppression, 1 and 12 months after heart transplantation. We investigated epicardial luminal diameter, coronary blood flow velocity, and ET-1 plasma levels at 1 and 12 months after transplantation. Structural coronary alterations were determined using intravascular ultrasound. RESULTS: Epicardial vasomotor function at baseline and during follow-up was comparable between the groups. Deterioration of microvascular endothelial function during follow-up was significantly enhanced in the CyA versus Tac group (p < 0.05). Circulating ET-1 concentration increased in the CyA group but significantly decreased over time in the Tac group (CyA +17% vs. Tac -25%; p < 0.05). The time-dependent increase in mean intimal area was significantly enhanced in the CyA versus Tac group, whereas the vessel area significantly increased during follow-up in the Tac compared with the CyA group. CONCLUSIONS: Epicardial endothelial function is comparable between CyA- and Tac-treated patients. Microvascular endothelial function deteriorates more in CyA-treated patients, a finding that correlates with enhanced ET-1 concentration and an increased intimal area during follow-up. The mean vessel area in the Tac group increased over time, indicating positive vascular remodeling. Tac is superior to CyA with respect to microvascular endothelial function, intimal thickening, and vascular remodeling. 相似文献
979.
Tumour necrosis factor alpha upregulates platelet CD40L in patients with heart failure 总被引:1,自引:0,他引:1
Pignatelli P Cangemi R Celestini A Carnevale R Polimeni L Martini A Ferro D Loffredo L Violi F 《Cardiovascular research》2008,78(3):515-522
AIMS: Patients with heart failure (HF) have elevated values of the pro-inflammatory protein CD40L but the underlying mechanism is unclear. This study was performed to evaluate the interplay between tumour necrosis factor alpha (TNFalpha) and CD40L in HF. METHODS AND RESULTS: In patients with HF (n=86) and healthy subjects (HS, n=43), plasma levels of soluble CD40L (sCD40L), TNFalpha, soluble receptors of TNFalpha such as soluble TNF receptors I and II (sTNFR1 and sTNFR2), and 8OH-dG, a marker of oxidative stress, were determined. Also, an in vitro study was performed by determining platelet CD40L regulation upon platelet stimulation with TNFalpha. Compared with HS, HF patients had higher plasma values of sCD40L, TNFalpha, sTNFR1 and sTNFR2, and higher platelet expression of TNFR1 and TNFR2 with a progressive increase from NYHA I to NYHA IV classification. sCD40L significantly correlated with TNFalpha, sTNFR1, and sTNFR2; plasma levels of TNFalpha significantly correlated with sCD40L. Incubation of platelets from HF patients with a TNFalpha receptor inhibitor significantly decreased platelet CD40L expression. The in vitro study demonstrated that TNFalpha significantly increased CD40L expression, an effect weakly influenced by aspirin but significantly reduced by AACOCF3, an inhibitor of PLA(2), apocynin, an inhibitor of NADPH oxidase, or staurosporine, an inhibitor of PKC. CONCLUSION: The study shows that in HF patients, platelet CD40L is upregulated by TNFalpha via a cyclooxygenase-1-independent, arachidonic acid-mediated oxidative stress mechanism. 相似文献
980.
Bravo G Duguet AM Dubois MF Delpierre C Vellas B 《Journal of cross-cultural gerontology》2008,23(3):239-253
The authors first describe the rules enacted in Quebec and France to protect adults with decisional impairment who may be approached by investigators to participate in research protocols. They then present two consecutive postal surveys conducted among Quebec and French researchers in aging and designed to (1) assess their knowledge of the legal provisions implemented to protect decisionally incapable adults, (2) elicit their opinions regarding the person best suited to provide substitute consent for research participation, and (3) document their conduct related to obtaining consent for prospective subjects with impaired decisional capacity. Knowledge of the legislation governing substitute consent was poor, even more so among French than Quebec researchers (p < 0.001). In both samples, the majority of respondents felt that the substitute decision-maker does not have to be legally appointed when the study poses little risk to the participant. Practice data revealed a certain discrepancy between the conduct of researchers in aging and the legal provisions regarding consent for research purposes that prevail in their jurisdictions. These findings underscore the need to better educate clinical investigators about existing measures to protect prospective subjects who lack decisional capacity. They also provide some support for allowing close relatives to consent to research participation on behalf of older adults who are unable to consent by themselves and have not been appointed a legal representative. 相似文献