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OBJECTIVE: The backward effects of left ventricular dysfunction include alterations in alveolar-capillary gas transfer and ventilation-perfusion coupling. Because the angiotensin-converting enzyme (ACE) is highly concentrated in the vascular endothelium of the lungs, we examined whether ACE inhibitors may influence the pulmonary function in patients with congestive heart failure. METHODS: In 20 patients with idiopathic cardiomyopathy, pulmonary function and exercise capacity were evaluated at baseline and 6 and 12 months after treatment with enalapril (10 mg twice a day) was started. The study also included 19 age- and sex-matched control subjects with mild primary hypertension and normal left ventricular function who were given enalapril as a standard treatment of high blood pressure. RESULTS: In congestive heart failure, forced expiratory volume in 1 second, vital capacity, and total lung capacity did not vary significantly with enalapril; alveolar-capillary diffusion of carbon monoxide (DL(CO)) increased toward normal; exercise tolerance time, peak exercise oxygen uptake (peak VO2), minute ventilation and tidal volume (peak VT) also increased; and the ratio of volume of dead space (VD) to VT (peak VD/VT) at peak exercise reduced. Changes in peak VO2 showed a direct correlation with those in DL(CO) and an inverse correlation with those in peak VD/VT. Results at 6 and 12 months were comparable. Enalapril did not affect these variables in the control population. CONCLUSIONS: In patients with idiopathic cardiomyopathy heart failure, but not in control subjects, gas transfer and ventilation-perfusion improved with ACE inhibition. These pulmonary changes may contribute to the associated increase in exercise tolerance.  相似文献   
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In the present investigation insulin-induced hypoglycemia was used as a powerful stimulus to rapidly release epinephrine from the adrenal medulla. Insulin injection raised epinephrine 16-fold and doubled norepinephrine plasma levels. The aim of this attempt was to induce beta-adrenergic receptors (beta-ARs) sequestration in vivo on mononuclear leukocytes (MNLs). The number of total and surface beta-ARs was significantly increased 30 minutes after insulin administration, with only partial recovery at 90 minutes. No detectable receptor sequestration was observed: surface receptors were about 90% of total receptors in all the conditions examined. Isoproterenol-stimulated cyclic adenosine monophosphate (cAMP) accumulation was also increased after 30 minutes (+66%) and 90 minutes (+65%) of insulin injection. Basal and forskolin-stimulated intracellular cAMP values were unchanged. We conclude that, even after a strong release of catecholamines, beta-AR redistribution cannot be demonstrated on MNLs.  相似文献   
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Prevalence and characteristics of brittle diabetes in Britain   总被引:3,自引:0,他引:3  
We investigated the prevalence and characteristics of 'brittle diabetes', defined as insulin-dependent diabetes mellitus associated with glycaemic instability of any type, leading to life disruption with recurrent and/or prolonged hospitalizations. A questionnaire was sent to all physicians and paediatricians running diabetic clinics in the UK, from lists held at the British Diabetic Association. A total of 414 brittle patients were reported (72% questionnaire return). Most were young (mean age +/- SD was 26 +/- 15 years), though there was a small peak at ages 60-70 years. There was an excess of females (66%) and overall clinic prevalence was 1.2 per 1000 diabetic patients and 2.9 per 1000 insulin-treated diabetic patients. On average, there was 1.0 brittle patient per diabetic clinic. The most common form of brittleness was recurrent ketoacidosis (59%), with 17% having predominant hypoglycaemia, and 24% mixed instability. Female excess was highest and mean age lowest in the recurrent ketoacidosis group, whilst the reverse was true for those with recurrent hypoglycaemia. Causes of brittleness were offered by 58% of consultants, and most (93%) considered various psychosocial problems as likely underlying factors. We conclude that brittle diabetes is a small but significant problem, currently affecting about 1 per 1000 diabetic patients. Most, but by no means all, are young females--often with recurrent ketoacidosis. Older age groups are more likely to have recurrent hypoglycaemic or mixed types of brittleness. Perceived causes of brittleness are usually psychosocial.   相似文献   
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SUMMARY Analysis of the age of onset of diabetes amongst insulin-treatedpatients in a large African diabetic clinic revealed a bimodaltype of distribution, 23 per cent having an age of onset before30 years and 77 per cent with onset at 30 years of age. All66 of the young insulin-treated group (21.7±4.8 years(mean±1 SD)), and a random selection of 50 older insulin-treatedpatients (49.7±10 years), were studied. The older groupwere better controlled (HbA1 8.4±1.7 per cent vs. 10.8±2.6per cent, p<0.001), on lower doses of insulin (49±23vs. 71±23 u/day, p<0.001) and had higher body massindex (26.0±5.6 vs. 21.8±3.5, p<0.001). SerumC-peptide (0.24±0.15 vs. 0.07±0.10 nmol/l, p<0.0001),and C-peptide/glucose ratio (2.57±2.65 vs. 0.56+0.98nmol/mmolx 102, p<0.001) were very significantly higher inolder patients. Patients with later onset disease thus had betterpreservation of pancreatic function, higher body mass indexand better glycaemic control on lower doses of insulin. Thesefeatures suggest that older insulin-treated patients could infact be ‘Type 2’ or non-insulin dependent patients,and the condition may be controllable with diet and/or oralhypoglycaemic agents, at least in some.  相似文献   
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Several levodopa/carbidopa intestinal gel (LCIG) studies showed a significant reduction of OFF time and a significant increase of ON time, as well as a reduction of dyskinesia, and improvement of non-motor symptoms and quality of life. However, few studies have been conducted in a large population for more than 3 years. Interim outcomes from GREENFIELD observational study on a large Italian cohort of advanced PD patients who started LCIG in routine care between 2007 and 2014, still on treatment at the enrollment, are presented. Comparison between baseline (before LCIG start) and visit 1 (at enrollment) is reported. Primary endpoint was Unified Parkinson’s Disease Rating Scale (UPDRS) IV Item 39; secondary endpoints were UPDRS I and II, as outcome of quality of life. Overall, 145 of 148 enrolled patients from 14 Movement Disorder Centers in Italy were evaluable with a mean LCIG treatment period of 1.38 ± 1.66 years at enrollment. Compared with baseline, the mean score regarding daily time spent in OFF (UPDRS IV Item 39) at visit 1 significantly decreased from 2.1 ± 0.8 to 0.9 ± 0.7 (57 % reduction vs baseline, P < 0.0001); UPDRS IV improved by 39 % (P < 0.0001); scores for dyskinesia duration and disability were reduced by 28 % (1.8 ± 1.0–1.3 ± 0.9; P < 0.0001) and 33 % (1.5 ± 1.1 to 1.0 ± 1.0; P < 0.0001), respectively; and the scores for painful dyskinesia and early morning dystonia were reduced by 56 % (0.9 ± 1.0–0.4 ± 0.7; P < 0.0001) and 25 % (0.4 ± 0.5–0.3 ± 0.5; P < 0.001), respectively. The preliminary results of this interim analysis support the efficacy of LCIG on motor complications and activities of daily living.  相似文献   
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Eleven consecutive patients with a first episode of acute optic neuritis were evaluated, using conventional and magnetization transfer (MT) magnetic resonance imaging (MRI), in order to assess the temporal evolution of optic nerve (ON) damage and to investigate the correlation of ON damage with visual outcome and electrophysiological parameters. Patients underwent neuroophthalmological, neurological, electrophysiological, and MRI assessments at baseline and after three and 12 months. ON volumes were measured on coronal T1-weighted images using a local thresholding segmentation technique. MT ratio (MTR) from the ON was derived from gradient echo images. No significant volume difference was detected between affected and healthy ON, both at baseline and follow-up. At baseline, mean MTR values were significantly higher in affected ON than in healthy ON (P =0.001), whereas at months 3 and 12, the mean MTR values were significantly reduced in the affected ON (P =0.02 and 0.003, respectively). Mean MTR of the affected ON, corrected for healthy ON values, progressively decreased over time (P =0.04 at month 3 and P =0.0012 at month 12). On the contrary, MTR values of healthy ON remained stable. No correlations were found between MTR measures and clinical or electrophysiological data. This study shows the presence of subtle pathological changes, possibly due to residual demyelination and subsequent additional demyelination and impaired remyelination, in the ON of patients with a first episode of optic neuritis. In the early phase of optic neuritis, MT MRI is more sensitive than atrophy measurements in detecting disease-related changes.  相似文献   
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Late restenosis following sirolimus-eluting stent implantation   总被引:1,自引:0,他引:1  
Despite encouraging results from randomized trials, concerns exist about long-term results of sirolimus-eluting stent implantation. We sought to determine whether in-stent restenosis occurring >1 year ("late") after sirolimus-eluting stent implantation is a real clinical entity. We analyzed data on all sirolimus-eluting stents implanted in our institution before March 2003. During the study period 928 lesions in 433 patients were treated. Angiographic follow-up was performed in 306 patients (70.6%) with 679 lesions (73.2%). Angiography after 1 year was performed only in symptomatic patients. We considered restenosis "early" if it occurred during the first year and late if after 1 year. Late restenosis required demonstration of a widely patent stent at 6 to 9 months, with repeat angiography after 1 year demonstrating restenosis. Restenosis occurred in 160 lesions overall (23.5%). Of the 31 (4.6%) that were documented after 1 year, 13 were excluded from analysis due to absence of 6- to 9-month angiography; the remaining 18 (2.6%, 1.7 to 4.2) fulfilled our criteria for late restenosis (median time of documentation 607 days, interquartile range 511 to 923). In conclusion, late restenosis is an infrequent but real entity; its existence implies we should not discount the possibility of restenosis as the cause of symptoms that develop >1 year after sirolimus-eluting stent implantation.  相似文献   
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