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91.
BACKGROUND: The prognostic role of endothelial dysfunction, as evaluated by flow-mediated vasodilatation of the brachial artery, has been demonstrated in patients at very high risk. We aimed to investigate whether flow-mediated vasodilatation predicts cardiovascular events in uncomplicated hypertensive patients. METHODS AND RESULTS: A total of 172 prospectively identified uncomplicated hypertensive patients (age 56 +/- 8 years, 41% women, 48 with diabetes mellitus type 2) were studied. At baseline all patients were untreated and underwent baseline standard laboratory examination. A standard echocardiogram was performed for the evaluation of left ventricular anatomy and function and patients with systolic dysfunction or left ventricular wall motion abnormalities were excluded. Endothelial function was measured as flow-mediated vasodilatation of the brachial artery using high-resolution ultrasound. Patients were followed for 95 +/- 37 months (range 2-136 months). A first nonfatal or fatal cardiovascular event occurred in 32 patients. The incidence of cardiovascular events was 1.4 and 3.1 per 100 patient-years in patients with a flow-mediated vasodilatation below and above the median value (4.7%), respectively (P < 0.005 by the log-rank test). In Cox analysis, controlling for age, sex, glycemia, cholesterol, smoking, BMI, systolic and diastolic blood pressure at baseline and left ventricular mass index, a low flow-mediated vasodilatation conferred an increased risk of cardiovascular events (odds ratio 2.67, 95% confidence interval 1.17 to 6.1, P = 0.02). CONCLUSION: The presence of endothelial dysfunction, as evaluated by flow-mediated vasodilatation of the brachial artery, identifies hypertensive patients at increased risk of nonfatal and fatal cardiovascular events.  相似文献   
92.
Assessment of appropriateness of left ventricular mass (LVM) for a given workload may better stratify hypertensive patients. Inappropriate LVM may reflect the interaction of genetic and neurohumoral factors other than blood pressure playing a significant role in myocardial growth. Primary aldosteronism (PA) represents a clinical model useful in assessing the effect of aldosterone increase on LVM. The aim of this study was to evaluate the inappropriateness of LVM in patients with PA. In 125 patients with PA (54 females; adrenal hyperplasia in 73 and adenoma in 52 patients) and in 125 age-, sex-, and blood pressure-matched, essential hypertensive patients, echocardiography was performed. The appropriateness of LVM was calculated by the ratio of observed LVM to the predicted value using a reference equation. In all of the subjects plasma renin activity and aldosterone, as well as clinic and 24-hour blood pressure, were measured. The prevalence of inappropriate LVM was greater in patients with traditionally defined left ventricular hypertrophy (70% and 44%, respectively; P=0.02) but also in patients without left ventricular hypertrophy (17% and 9%, respectively; P=0.085). In PA patients, a correlation was observed between the ratio of observed:predicted LVM and the ratio of aldosterone:plasma renin activity levels (r=0.29; P=0.003) or the postinfusion aldosterone concentration (r=0.44; P=0.004; n=42). In conclusion, in patients with PA, the prevalence of inappropriate LVM is increased, even in the absence of traditionally defined left ventricular hypertrophy. The increase in aldosterone levels could contribute to the increase of LV mass exceeding the amount needed to compensate hemodynamic load.  相似文献   
93.
94.
Several studies in the literature investigated the association between temporomandibular disorders (TMD) and otogenous symptoms, like vertigo, tinnitus, otalgia and muffling, although the question of the existence of a cause-effect relationship is still controversial. Epidemiological findings showed that the prevalence of ear symptomatology in the general population is variable from 10% to 31%, and increases up to 85% in TMD patients. Based on these data, many attempts have been performed to describe the physiopathological interactions between aural symptoms and TMD, as a strict anatomical link exists between the structures of the ear and those of the stomatognathic system. Unfortunately, methodological weaknesses of most studies are evident so that the comparison of results is often difficult. Considering these premises, the present study critically reviewed the literature on this debated issue, discussing the main etiopathogenetic hypotheses, the features of ear symptomatology in TMD patients and its relationship with TMD treatment in order to present current suggestions about the relationship between aural and TMD symptoms. Suggestions for future researches have been also presented, since a full understanding of this plausible interaction will be an important factor in diagnosis making and treatment planning for both pathologies.  相似文献   
95.
BACKGROUND: A number of patients with chronic heart failure (CHF) have diastolic but not systolic dysfunction. This occurs particularly in the elderly and in hypertension, but the prevalence of diastolic dysfunction in elderly hypertensives without CHF has never been investigated systematically. METHODS AND RESULTS: The Assessment of PRevalence Observational Study of Diastolic Dysfunction (APROS-diadys) project was a cross-sectional observational study on elderly (age >/= 65 years) hypertensives without systolic dysfunction [left ventricular ejection fraction (LVEF) >/= 45%] consecutively attending hospital outpatient clinics in Italy, in order to establish the prevalence of echocardiographic signs of diastolic dysfunction according to various criteria, and to correlate them with a number of demographic and clinical characteristics. Primary criteria for diastolic dysfunction was an E/A ratio (ratio between transmitral peak velocities of E and A waves) < 0.7 or > 1.5 on echocardiographic Doppler examination. Secondary criteria were: E/A < 0.5 and deceleration time (DT) > 280 ms, or isovolumic relaxation time (IVRT) > 105 ms or pulmonary vein (PV) peak systolic/peak diastolic flow (S/D) ratio > 2.5 or PV atrial retrograde flow (PV A) > 35 cm/s. Throughout Italy, 27 447 patients were screened in 107 clinics, with 24 141 excluded according to protocol. Among the remaining 3336 patients, 754 (22.6%) had signs of CHF. After exclusion of 37 protocol violators, 2545 patients (49.0% men, mean age 70.3 years, 95.4% under antihypertensive treatment) were studied ultrasonographically. Diastolic dysfunction (primary criteria) was found in 649 (25.8%) patients. Multiple logistic regression analysis found age, gender, left ventricular mass, systolic and pulse pressures and midwall shortening fraction as significant covariates. Using secondary criteria, the prevalence of diastolic dysfunction was higher (45.6%), mostly because of IVRT > 105 ms or PVA flow > 35 cm/s. CONCLUSION: CHF and diastolic dysfunction are highly prevalent in elderly hypertensives attending hospital clinics.  相似文献   
96.
Though recent progress in multiple sclerosis (MS) treatment is remarkable, numerous unmet needs remain to be addressed often inducing patients to look for complementary and alternative medicines (CAM), especially herbal remedies (HR). HR use, scarcely investigated in MS, may cause adverse reactions (AR) and interfere with conventional treatment. We performed a survey aimed at evaluating use and attitudes towards HR and factor associated to HR use. Other CAM use and attitudes have been investigated as well. Multiple-choice questionnaires were distributed to MS out patients attending 14 Italian referral Centers. Multivariable logistic regression was used to identify HR use determinants. Present/past HR use for either MS or other diseases was reported in 35.6 % of 2419 cases (95 % CI 36.0–40.0 %). CAM use was reported in 42.5 % of cases. Independent predictors of HR use were represented by higher education, geographic area, dissatisfaction with conventional treatment of diseases other than MS and benefit perception from CAM use. Both HR and CAM use were not always disclosed to the healthcare professional. In conclusion, HR and other CAM appear to be popular among MS patients. The involvement of the healthcare professionals appears to be scarce with potential risk of AR or interference with conventional treatments.  相似文献   
97.
98.
Cytochrome P450 (CYP) enzymes of nasal tissue are relatively resistant to induction by classical inducers. In the present study, the effects of starvation on the expression of CYP1A, 2A, 2B, 2C, 2E, 2G, and 3A subfamilies in the nasal mucosa of rat were studied. Fasting for 72 hr caused an increase in 2E1-dependent p-nitrophenol hydroxylase and 1A-dependent ethoxy- (or methoxy) resorufin dealkylase activities, but did not affect either 2A-linked coumarin hydroxylase or the testosterone hydroxylase activity, the latter reaction being a marker of several CYPs including 2G1. Whereas increases in 2E1- and 1A- associated catalytic activities were accompanied by a concomitant increase in the corresponding apoproteins as determined by immunoblotting, immunoactive protein bands reactive with antibodies raised against rat 1A1, 2B1, 2C11, 3A1 or rabbit nasal 2A10/11 and 2G1 were not altered. Fasting also increased CYP2E1 and CYP1A2 on the mRNA level, but did not alter CYP1A1 mRNA as determined by hybridization with cDNA probes selective for these cytochromes. A reiterative administration of chlormethiazole, a specific inhibitor of 2E1 in liver, strongly inhibited many CYPs, including 2E1, 1A2, 2G1, and 2A in the nasal mucosa, but did not influence expression of 2B or 3A as determined by immunoblotting or catalytic activities. The chlormethiazole-mediated inhibition of 1A1 and 2E1 was demonstrated to be at the mRNA level. These results suggest that fasting induces the gene expression of 2E1 and 1A2 and that the mechanisms involved in the regulation of CYPs in the nasal mucosa are tissue-specific. The inducibility of the above-mentioned isoforms may have a significant role in the clearance of drugs and bioactivation of inhaled compounds.  相似文献   
99.
Elevated plasma homocyst(e)ine levels have prothrombotic and proatherosclerotic effects. Data from prospective studies indicated that plasma homocyst(e)ine acts as a modest independent predictor of coronary heart disease. At present, no conclusive data are available on the possible interaction between hyperhomocyst(e)inemia and hypertension and the occurrence of cardiovascular events. Recent longitudinal studies in high risk patients indicated that hyperhomocyst(e)inemia is strongly associated with recurrent cardiovascular events. However, this finding is not in line with the few available data from prospective studies, which failed to observe a protective role of homocyst(e)ine-lowering therapy in secondary prevention of cardiovascular events. Future results from ongoing larger trials are expected to provide more definitive answers concerning the need to support the routine use of folic acid in patients with CHD. Since the definitive impact of mild hyperhomocyst(e)inemia on coronary heart disease is still to be established, widespread determination of homocyst(e)ine levels is not needed in a general population at the present time. In contrast, knowledge of homocyst(e)inemia may be important for specific groups of individuals, such as high risk patients, and for those patients in whom traditional risk factors do not appear to account for an increased incidence of cardiovascular events.  相似文献   
100.
Subsequent to a genomic linkage study on Sardinian and Continental Italian families, we considered the possibility that some of the tested microsatellite markers showed association to MS. Markers selected on the basis of the data obtained in the original set of 70 multiplex families were tested for MS association in an additional set of 154 simplex families. A limited set of markers were further tested on an additional set of 100 simplex families. The results indicate the presence of a putative MS gene in 19q13.13.  相似文献   
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