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981.
We investigated the effects of viral infection on Tissue Factor (TF) expression and activity in mice within the myocardium to understand increased thrombosis during myocarditis. Mice were infected with coxsackie virus B3 (CVB3) and the hearts were collected at day 4, 8 and 28 post infection (p.i.). Myocardial TF expression and cellular activity as well as plasma activity were analyzed from CVB3 infected mice by Western blot, chromogenic Factor Xa generation assay, in situ staining for active TF and immunohistochemistry. In addition to TF expression, hemodynamic parameters were measured during the time course of infection. Furthermore, we analyzed myocardial tissues from patients with suspected inflammatory cardiomyopathy. TF protein expression was maximally 5-fold elevated 8 days p.i. in mice and remained increased on day 28 p.i. (P < 0.001 vs. non-infected controls). Alterations in TF expression were associated with fibrin deposits within the myocardium. The TF pathway inhibitor protein expression in the myocardium was not altered during myocarditis. Active cellular TF co-localized with CD3 positive cells and VCAM-1 positive endothelial cells in the myocardium. The TF expression was positively correlated with the amount of infiltrating CD3 and Mac3 positive cells (Spearman-Rho ρ = 0.749 P < 0.0001 for CD3+ and ρ = 0.775 P < 0.0001 for Mac3+; N = 35). Increased myocardial TF expression was associated with a 2-fold elevated plasma activity (P < 0.05 vs. non-infected controls). In the human hearts, the TF expression correlated postively with an endothelial cell activation marker (ρ = 0.523 P < 0.0001 for CD62E; N = 54). Viral myocarditis is a hypercoagulative state which is associated with increased myocardial TF expression and activity. Upregulation of TF contributes to a systemic activation of the coagulation cascade.  相似文献   
982.

Purpose of Review

This review aims to examine gender differences in both the epidemiology and pathophysiology of hypertension and to explore gender peculiarities on the effects of antihypertensive agents in decreasing BP and CV events.

Recent Findings

Men and women differ in prevalence, awareness, and control rate of hypertension in an age-dependent manner. Studies suggest that sex hormones changes play a pivotal role in the pathophysiology of hypertension in postmenopausal women. Estrogens influence the vascular system inducing vasodilatation, inhibiting vascular remodeling processes, and modulating the renin-angiotensin aldosterone system and the sympathetic system. This leads to a protective effect on arterial stiffness during reproductive age that is dramatically reversed after menopause.

Summary

Data on the efficacy of antihypertensive therapy between genders are conflicting, and the underrepresentation of aged women in large clinical trials could influence the results. Therefore, further clinical research is needed to uncover potential gender differences in hypertension to promote the development of a gender-oriented approach to antihypertensive treatment.
  相似文献   
983.
This experiment was designed to determinemechanisms of change in nonadrenergic, noncholinergic(NANC) inhibitory neurons in the ileum after small boweltransplantation (SBT) in the rat and whether nitric oxide (NO) serves as an important NANCinhibitory neurotransmitter in the rat ileum. Eightgroups of rats (N 8 rats/group) were studied:neurally intact unoperated controls; rats one week afteranesthesia and sham celiotomy; and separate groups one andeight weeks after either 40 min of cold ischemia of thejejunoileum, combined jejunal and ileal intestinaltransection/reanastomosis, or orthotopic SBT of the entire jejunoileum. Contractile activitywas evaluated in full-thickness ileal circular musclestrips under isometric conditions. Spontaneous activitydid not differ among groups. In all groups, exogenous NO, NG-monomethyl-L-arginine(L-NMMA, an NO synthase inhibitor), and methylene blue(soluble guanylate cyclase inhibitor) had no effect onspontaneous activity, while 8-bromocyclic guanosinemonophosphate (8Br-cGMP) inhibited contractile activity inall groups. Low frequency (2-10 Hz) electrical fieldstimulation (EFS) inhibited contractile activity only incontrol and SBT groups; L-NMMA and methylene blue did not alter the response to EFS in any group.These results suggest that each aspect of the SBTprocedure, ischemia/reperfusion injury, disruption ofenteric neural continuity by intestinal transection, and extrinsic denervation, alter function ofenteric ileal inhibitory neurons separately early (oneweek) after operation. NO, a known inhibitoryneurotransmitter in other gut regions, does not affectileal circular muscle in neurally intact tissue normediate functional changes in inhibitory nerve functionnor smooth muscle contractility after SBT.  相似文献   
984.
985.
OBJECTIVES: To determine the prognostic role of orthostatic hypotension for cardiovascular disease (CVD) and all‐cause mortality in elderly people. DESIGN: Prospective study. SETTING: Community based. PARTICIPANTS: Five thousand sixty‐four subjects from the Rotterdam study aged 55 and older. MEASUREMENTS: Orthostatic hypotension was measured using a Dinamap automatic blood pressure recorder. Orthostatic hypotension is defined as a decline in systolic blood pressure of 20 mmHg or more or a decline in diastolic blood pressure of 10 mmHg or more from supine to standing position at any of three measurements taken 1, 2, and 3 minutes after standing. RESULTS: At baseline, 901 subjects had orthostatic hypotension. During follow‐up, 668 subjects had coronary heart disease (CHD) (mean follow‐up 6.0 ± 3.5 years), and 1,835 subjects died (mean follow‐up period 7.8 ± 3.8 years). Orthostatic hypotension increased the risk of CHD (hazard ratio (HR)=1.31, 95% confidence interval (CI)=1.08–1.57) and all‐cause mortality (HR=1.22, 95% CI=1.09–1.36), in models adjusted for age and sex. The risk was slightly lower after additional adjustment for cardiovascular risk factors. In analyses stratified for age, the HRs for all‐cause mortality were 1.80 (95% CI 1.25–2.60), 1.13 (0.89–1.42), and 1.27 (95% CI=1.11–1.44), in the first, second, and third tertile of age, respectively. CONCLUSION: Orthostatic hypotension increases the risk of CHD and all‐cause mortality in elderly people. The risk of CVD and mortality is strongest in younger and very old subjects.  相似文献   
986.
Transesophageal overdrive atrial pacing is effective and safe for atrial flutter termination. The influence of antiarrhythmic drug therapy on this procedure is controversial. In this study, we investigated whether oral propafenone may facilitate this procedure. Thirty patients with type I atrial flutter were randomized into 2 groups in which transesophageal pacing was attempted: group A, without treatment; and group B, after oral administration of propafenone 600 mg. Transesophageal pacing was effective in interrupting atrial flutter in 53% of patients (8 of 15) in group A and in 87% of patients (13 of 15) in group B. A significant lengthening of the flutter cycle was observed with respect to the baseline in patients given propafenone (261 ± 23 vs 217 ± 25, p < 0.01). Sinus rhythm resumed at a shorter paced cycle in group A patients (166 ± 13 vs 187 ± 14 ms, p < 0.01). The transesophageal threshold for stable atrial capture was significantly lower in group A (20.5 ± 0.2 vs 23.3 ± 1.2, p < 0.01). In no patient was the threshold for atrial capture higher than the pain threshold. We did not observe abrupt enhancement of atrioventricular conduction. We conclude that propafenone is effective and safe when used with transesophageal pacing in the termination of atrial flutter. The slowing effect of the drug on intraatrial conduction and the possible stabilizing effect on the reentry circuit appear to be outweighed by the positive effect of propafenone on the excitable gap of the circuit, facilitating its capture and accounting for the beneficial effect of the drug on arrhythmia termination.  相似文献   
987.
988.
BACKGROUND: Duodenal duplication cysts are rare congenital anomalies. Symptomatic cases have classically been treated by surgical resection, which can be complex because of the close proximity of the cysts to the papilla. OBJECTIVE: To describe a series of 8 patients with symptomatic duodenal duplication cysts who were treated endoscopically, with a special focus on the long-term outcome. DESIGN: Retrospective case series. SETTING: Three tertiary-care European academic hospitals. PATIENTS: Eight patients, age 8 to 72 years, were treated endoscopically for symptomatic intraluminal duodenal duplication cysts between 1981 and 2006. Seven patients presented with acute pancreatitis, and one patient presented with jaundice. INTERVENTION: Endoscopic incision and marsupialization of the cysts was performed by using a variety of endoscopic tools (needle-knife and regular sphincterotomes, cystotomes, and polypectomy snares). MAIN OUTCOME MEASUREMENTS: Technical success of endoscopic intervention and long-term clinical recurrence of symptoms. RESULTS: No major complications occurred. All patients remained asymptomatic at a median follow-up of 7.3 years. LIMITATIONS: Retrospective study; the small number of patients. CONCLUSIONS: The endoscopic treatment of symptomatic intraluminal duodenal duplication cysts is a safe and effective technique, with excellent long-term results. It represents a minimally invasive alternative to surgical resection and might be considered the preferred therapeutic modality for these cases.  相似文献   
989.
Percutaneous revascularization of saphenous vein grafts (SVGs) remains a challenging task. Drug-eluting stents (DESs) have been shown to decrease the incidence of restenosis in de novo native coronary artery lesions. However, their clinical value in SVGs remains to be established. We compared long-term clinical outcomes of percutaneous coronary intervention with DESs and bare metal stents (BMSs) for de novo lesions in SVGs. In a large prospective, multicenter registry, 360 patients underwent stenting of a de novo lesion in SVGs using BMSs (288 patients) or DESs (72 patients). Incidence of major adverse cardiac events (MACEs), including all-cause mortality, reinfarction, and target vessel revascularization, was recorded at a 12-month follow-up. Compared with the DES group, patients receiving BMSs were more likely to be men, to have chronic renal insufficiency or higher Charlson scores, but less likely to have undergone previous percutaneous coronary intervention. Incidence of MACEs at 12-month follow-up was similar in the 2 groups (17.8% in DES group vs 20.3% in BMS group, respectively, p = 0.460). Cox regression analysis identified age, chronic renal failure, cardiogenic shock at presentation, and ostial location of stenosis as independent predictors of long-term MACEs. In conclusion, our data suggest that rates of 12-month MACEs associated with the use of DESs and BMSs are similar in patients undergoing treatment of de novo lesions in SVGs.  相似文献   
990.
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