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Two new T cell subsets may be involved in allergic rhinitis (AR) pathogenesis: Th17 and T regulatory cells, mainly producing IL-17 and TGF-β respectively. Successful Sublingual Immunotherapy (SLIT) induces relevant immunological changes, thus the aim of this study was to evaluate serum IL-17 and TGF-β levels in AR patients treated with SLIT for 2 years. Patients' blood samples were collected before initiating SLIT (baseline), three months after the end of the first pre-seasonal SLIT course, and at the end of the second pre-seasonal course. IL-17 was detectable only in the most severe allergic patients. SLIT significantly induced an increase in serum TGF-β levels. There was moreover a significant relationship between TGF-β and symptom severity and drug use at the end of the study. Therefore, this study provides clinically relevant evidence that two pre-seasonal SLIT courses may significantly affect serum TGF-β levels.  相似文献   
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OBJECTIVE: The effects of major lung resections on cardiac function in the medium and long term have not been thoroughly evaluated. We have studied right heart function with serial Doppler echocardiography in patients undergoing lobectomy and pneumonectomy during 4 years of follow-up after surgery. METHODS: Thirty-six patients undergoing lobectomy and 15 receiving pneumonectomy were evaluated with one- and two-dimensional Doppler standard transthoracic echocardiography before surgery and 1 week, 3 months, 6 months, 1 year, and 4 years postoperatively. We have studied the right midventricular diastolic diameter (RVDD), the right ventricle free wall thickness, the tricuspid valve insufficiency (TVI) and regurgitation jet (TRJ), and the pulmonary artery systolic pressure (PASP). RESULTS: None of the patients died within the first postoperative year. After lobectomy there were no significant modifications of any variable at any time. RVDD progressively increased after pneumonectomy (26.5+/-2.2mm preoperatively vs 34.3+/-7.6 at 4 years; p<0.001). Four years after surgery all patients undergoing pneumonectomy had moderate TVI while only 55% of patients receiving lobectomy showed it (low grade in 50% and moderate in 5%). In this group of patients PASP increased from 26.1+/-2.6 mmHg preoperatively to 34.3+/-7.6 mmHg at 4 years (p<0.00001). CONCLUSIONS: Right ventricle modifications are clearly evident after pneumonectomy and even if they do not show a clear clinical impact they should not be neglected.  相似文献   
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Pulmonary arterial hypertension (PAH) is a disease of the small vessels in which there is a substantial increase in pulmonary vascular resistance leading to right ventricle failure and death. Invasive haemodynamic evaluation is mandatory not only for diagnosis confirmation but also to address prognosis and eligibility for the use of calcium-channel blockers through an acute vasodilator challenge. Noninvasive surrogate response markers to the acute vasodilator test have been sought. In the present study, the relationship between pulmonary artery distensibility, assessed using magnetic resonance imaging (MRI), and response to acute vasodilator tests was investigated. In total, 19 patients diagnosed with idiopathic PAH without any specific treatment were evaluated. Within a 48-h window after pulmonary artery catheterisation, patients underwent cardiac MRI. Cardiac index, calculated after the determination (invasively and noninvasively) of cardiac output, showed excellent correlation, as did right atrial pressure and right ventricle ejection fraction. Pulmonary artery distensibility was significantly higher in responders. A receiver operating characteristic curve analysis has shown that 10% distensibility was able to differentiate responders from nonresponders with 100% sensitivity and 56% specificity. The present findings suggest that magnetic resonance imaging and pulmonary artery distensibility may be useful noninvasive tools for the evaluation of patients with pulmonary hypertension.  相似文献   
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We studied the effects of dipyridamole and RA-642 on the production of superoxide anions and on oxygen radicals-induced lipid peroxidation in lens tissue homogenates from normal rats and rats given dipyridamole or RA-642 intraperitoneally. Superoxide production was evaluated by phenazine methosulphate (PMS)-induced nitroblue tetrazolium (NBT) reduction and lipid peroxidation by ferrous sulfate and ascorbic acid (FeAs)-induced malondialdehyde (MDA) production. Dipyridamole and RA-642 showed an inhibitory effect on both assays in the experiments with lens tissue homogenates from untreated or treated rats. The extent of inhibition, however, was significantly higher in pyrimidopyrimidinic-treated rats (range of inhibition at different times of incubation was 18% versus 23-57% for dipyridamole and 14% versus 73-80% for RA-642 in the assay of MDA production, and 10% versus 33-37% for dipyridamole and 2.5% versus 11-32% for RA-642 in the assay of NBT reduction). Concentrations of dipyridamole and RA-642 in lens tissue from treated animals could not be determined (less than 0.001 micrograms/mg of tissue). Although both compounds inhibited lipid peroxidation induced by oxygen free radicals, the mechanism of action might include the role of adenosine as a mediator.  相似文献   
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Epidemiologic studies have shown that blood pressure increases more rapidly in middle-aged women than in middle-aged men. Whether or not ovarian failure contributes to this rapid rise is still not clear. In a follow-up study begun in 1979 and to continue for 10 years, the blood pressure of 193 healthy normotensive perimenopausal women, who lived in the mixed rural/industrial community of Ede, the Netherlands and who were initially aged between 49 and 56 years, was measured annually. During the course of the study, the onset of menopause of each participant could be established. Because of the mixed longitudinal design of the study, it was possible to evaluate the effects of both chronologic aging and time pre- or postmenopause on blood pressure. After the first seven years of follow-up, it was demonstrated that blood pressure did not increase in 168 women whose body weight was relatively stable. After multivariate analyses, systolic as well as diastolic pressure showed a significant negative relation (slope, 1.34 mmHg per year and 0.63 mmHg per year, respectively) with the years since menopause. On the other hand, the observed positive relation (slope, 0.81 mmHg per year) of systolic pressure with chronologic aging was not significant. No consistent association was found between diastolic pressure and chronologic aging. It is concluded that menopause cannot be regarded as a cause of hypertension; on the contrary, ovarian failure appears to have a protective effect on the increase in blood pressure as a result of chronologic aging. on the increase in blood pressure as a result of chronologic aging.  相似文献   
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