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1.
A case of infantile Krabbe's disease was first recognised as areas of relatively increased density on CT in the thalamus lateral geniculate body and dentate nucleus. These sites were subsequently shown on MRI to have a paramagnetic effect, being characterised by short T2 and T1. Subsequent examinations showed development of atrophy and high signal in white matter.  相似文献   
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OBJECTIVES: LDL-cholesterol particles from hypertensive patients exhibit enhanced susceptibility to in vitro oxidation, an abnormality thought to increase cardiovascular risk. We tested whether blood pressure (BP) normalization can reverse this abnormality. DESIGN: Double-blind, randomized pharmacological intervention trial. SETTING: Clinical research centre. Subjects. A total of 29 nondiabetic, normolipidaemic patients with essential hypertension (BP= 151 +/- 3/99 +/- 1 mmHg) and 11 normotensive controls (BP=125 +/- 3/85 +/- 1 mmHg) matched for gender, age, obesity, glucose tolerance and lipid profile. Intervention. Anti-hypertensive treatment for 3 months with a calcium-antagonist in randomized combination with either an ACE inhibitor or a beta-blocker. MAIN OUTCOME MEASURES: Lag phase of copper-induced LDL oxidation, cell-mediated (human umbilical vein endothelium) generation of malondialdehyde (MDA) by LDL and vitamin E content in LDL. RESULTS: At baseline in hypertensives versus controls, lag phase was shorter (89 +/- 3 vs. 107 +/- 6 min, P < 0.04), MDA generation was higher (5.8 +/- 0.1 vs. 5.1 +/- 0.2 nmol L(-1), P=0.002), and vitamin E was reduced (6.40 +/- 0.05 vs. 6.67 +/- 0.11 microg mg(-1), P=0.03). At 3 months, BP was normalized (124 +/- 3/81 +/- 1, P < 0.0001 vs. baseline, P=ns versus controls), lag phase was prolonged (to 98 +/- 3 min, P=0.0005), MDA generation was reduced (5.6 +/- 0.1 nmol L-1, P = 0.001), and vitamin E was increased (6.53 +/- 0.05 microg mg(-1), P=0.003), with no significant differences between the randomized groups. CONCLUSIONS: In nondiabetic, nonobese, normolipidaemic patients with essential hypertension, LDL susceptibility to copper- and cell-mediated oxidation is increased. BP normalization is associated with a significant improvement, but not a full reversal, of this abnormality.  相似文献   
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Since recent findings suggest a relationship between reduction in adipose tissue blood flow (ATBF) and metabolic or vascular complications in obese patients (Ob-pts), increase in ATBF may be considered as a further goal in the treatment of obesity, besides fat mass reduction. Therefore, this preliminary study aimed at assess subcutaneous ATBF and vasomotion in morbidly obese patients and whether sustained weight loss induced by Roux-en-Y gastric bypass (RYGB) affects the same parameters. Using laser-Doppler flowmetry (LDF) and spectral Fourier analysis, subcutaneous ATBF was measured and subcutaneous ATBF oscillations (ATBF-O) were analyzed - within three frequency intervals related to vasomotion - in 16 Ob-pts, before and about one year after RYGB, and in 10 lean, healthy control subjects (CS). Before RYGB, Ob-Pts showed an important reduction in subcutaneous ATBF compared to CS (4.8 ± 2.7 PU vs 79.9 ± 34.5 PU, respectively; p < 0.0001), as well as higher normalized power spectral density (N-PSD) values of subcutaneous ATBF-O, - related to vasomotion. One year after RYGB, sustained weight loss in Ob-pts was associated with a slight but significant increase in subcutaneous ATBF (10.0 ± 6.6 PU, p < 0.05) and with almost complete normalization in N-PSD values of ATBF-O, related to vasomotion, compared to before RYGB. The slight subcutaneous ATBF increase, we observed in Ob-pts after sustained weight loss, moves toward a desirable goal. This finding suggests verifying whether an even more sustained weight loss in Ob-pts could determine a greater increase in subcutaneous ATBF and/or, more importantly, it could also determine a significant increase in visceral ATBF.  相似文献   
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BackgroundThe gene encoding catechol-O-methyltransferase (COMT) has been suggested as a candidate for Alzheimer-related psychosis (AD-P) susceptibility, and an association between AD-P and a functional valine to methionine polymorphism has been reported.ObjectiveThe aim of this study was to assess the genetic contribution of other COMT variants to the risk of AD-P.MethodsTwo hundred and forty-six AD patients underwent clinical and neuropsychological examination as well as an evaluation of behavioural and psychiatric disturbances. They were subsequently divided into two subgroups according to the presence (AD-P) or the absence (AD-nP) of psychotic symptoms. Four single-nucleotide polymorphisms (SNPs) within COMT gene were evaluated, i.e. rs737865, rs737864, intron 1 C2754delC, and the well-known valine/methionine variant (rs4680). Analyses were performed on the single locus and pairwise disequilibrium of loci, and multi-locus haplotype.ResultsThe individual SNP analysis confirmed an association for the valine/methionine variant with AD-P. Haplotype analyses revealed that the alleles at four loci (rs737865, rs737864, intron 1 C2754delC, rs4680) interacted to create the risk of psychosis in AD, as A-C-C-G haplotype (OR = 2.08, 95% CI = 1.02–4.27, P = 0.044) and G-C-delC-G haplotype (OR = 2.54, 95% CI = 1.32–4.90, P = 0.006) in respect to the most common and not-at-risk A-C-C-A haplotype which was significantly overrepresented in AD-P.ConclusionsThe present findings provide evidence of COMT genetic variations’ role in the susceptibility to AD-related psychosis. The observation of a haplotype effect of different polymorphisms within the COMT gene puts emphasis on the usefulness of haplotype analysis in better defining individualized genetic risk profiles in AD.  相似文献   
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A comparative study of the in vitro antioxidant activity of statins   总被引:11,自引:0,他引:11  
Background: Treatment of hypercholesterolemia with statins is remarkably effective in cardiovascular prevention. This has led to the hypothesis that these drugs may act on the atherosclerotic plaque by mechanism(s) independent of the reduction of serum cholesterol levels. The aim of this study was to assess the total antioxidant activity of the most prescribed statins: fluvastatin, atorvastatin, pravastatin and simvastatin. Methods: We measured the in vitro antioxidant activity of statins as their ability to antagonize the oxidation of -keto-γ-methiolbutyric acid by both hydroxyl and peroxyl radicals. The results are expressed as Total Oxyradical Scavenging Capacity (TOSC) units. Uric acid and Trolox were used as the reference antioxidants. Results: The scavenging capacity towards hydroxyl radicals was highest for simvastatin (3375±112 U/mg), a value 270.2% higher (P<0.0001) compared to uric acid (reference antioxidant vs. hydroxyl radicals, 1249±71 U/mg). Among the tested statins, fluvastatin exhibited the highest anti-peroxyl radical antioxidant capacity (8755±187 U/mg) which appeared 50% lower (P<0.0001) compared to Trolox (reference antioxidant vs. peroxyl radicals, 17 460±379 U/mg). Conclusions: All the statins tested have intrinsic antioxidant activity with both anti-hydroxyl and peroxyl radical activity. Simvastatin was the most effective as an anti-hydroxyl radical antioxidant and fluvastatin as an anti-peroxyl radical antioxidant.  相似文献   
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PURPOSE: To investigate ictal muscular phenomena characterizing symptomatic infantile spasms (ISs) and their relation to ictal EEG. METHODS: Four children with severe encephalopathy, neurologic impairment, and refractory ISs related to different dysplastic lesions, underwent videopolygraphic recordings collecting surface electromyogram (EMG) activity from several cranial and limb muscles to evaluate the pattern of muscular recruitment, duration, and side-to-side asymmetry of ISs. Acquired data were stored for off-line analysis by a computerized polygraphic system. RESULTS: Spasms were characterized by a complex pattern of muscular activation. A constant or rostrocaudal propagation pattern was lacking in all patients. Intervals between the onset of EMG activity in different muscles in each spasm were very long: 相似文献   
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VEPs were examined in ALL patients in order to test their usefulness in the detection of early and late CNS changes due to combined cranial X-irradiation and chemotherapy. The results suggest that: a)in patients free from self limited somnolence syndrome and visual symptoms, the VEP latency may be increased, probably because of early subclinical CNS changes due to cranial irradiation. b)late CNS changes (detected by routine neurological examination, EEG and CAT) seem to be correlated with increased VEP latency, even in the absence of visual symptoms.  相似文献   
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Functional microcirculatory aspects of burned sites were examined including areas of self-healed burns, and grafted areas. Donor areas were also examined. In 10 patients with burns in the lower limbs, both self-healed and with grafts, the microcirculatory response was evaluated by Laser Doppler flowmetry (LDF) measuring for each site the resting flux at 36 degrees, the postural venular-arteriolar reflex (VAR) and the flux at 41 degrees (heating). The first evaluation was carried out on discharge, and subsequently at approximately 45 day intervals during uniform therapy follow-up (elastocompression). The burn-affected area (self-healed, graft) and those donor areas present should increase resting flux by comparison with control areas. This was particularly so in the self-healed burn, which does however tend to converge in time towards control values. Response to stress tests (VAR and heating) presents percentage variations similar to normal skin in the various areas, with the exception of the grafted areas which present a reduced response in the 1st weeks following engraftment. No significant differences in response to heating were detected. It can be suggested that these differences are due to anatomic variations in revascularization and healing in the different areas as well as to alterations in microvascular innervation and local response to vasoactive substances.  相似文献   
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