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Background contextGadolinium-enhanced magnetic resonance imaging (Gd-MRI) is often performed in the evaluation of patients with persistent sciatica after lumbar disc surgery. However, correlation between enhancement and clinical findings is debated, and limited data are available regarding the reliability of enhancement findings.PurposeTo evaluate the reliability of Gd-MRI findings and their correlation with clinical findings in patients with sciatica.Study designProspective observational evaluation of patients who were enrolled in a randomized trial with 1-year follow-up.Patients samplePatients with 6- to 12-week sciatica, who participated in a multicentre randomized clinical trial comparing an early surgery strategy with prolonged conservative care with surgery if needed. In total 204 patients underwent Gd-MRI at baseline and after 1 year.Outcome measuresPatients were assessed by means of the Roland Disability Questionnaire (RDQ) for sciatica, visual analog scale (VAS) for leg pain, and patient-reported perceived recovery at 1 year. Kappa coefficients were used to assess interobserver reliability.MethodsIn total, 204 patients underwent Gd-MRI at baseline and after 1 year. Magnetic resonance imaging findings were correlated to the outcome measures using the Mann-Whitney U test for continuous data and Fisher exact tests for categorical data.ResultsPoor-to-moderate agreement was observed regarding Gd enhancement of the herniated disc and compressed nerve root (kappa<0.41), which was in contrast with excellent interobserver agreement of the disc level of the herniated disc and compressed nerve root (kappa>0.95). Of the 59 patients with an enhancing herniated disc at 1 year, 86% reported recovery compared with 100% of the 12 patients with nonenhancing herniated discs (p=.34). Of the 12 patients with enhancement of the most affected nerve root at 1 year, 83% reported recovery compared with 85% of the 192 patients with no enhancement (p=.69). Patients with and without enhancing herniated discs or nerve roots at 1 year reported comparable outcomes on RDQ and VAS-leg pain.ConclusionsReliability of Gd-MRI findings was poor-to-moderate and no correlation was observed between enhancement and clinical findings at 1-year follow-up.  相似文献   
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Background

Reversible posterior leukoencephalopathy syndrome (RPLS) is radiologically characterized by symmetrical subcortical areas of vasogenic edema that are preferentially parieto-occipital, and it typically resolves after appropriate treatment.

Case Report

We present a patient with strikingly unilateral RPLS that developed 21 days after coiling of an anterior communicating artery aneurysm and several days of triple-H therapy. Cortical and subcortical vasogenic edema and enhancement developed only in the left hemisphere, with a pattern suggesting RPLS. After 7 months the lesions had nearly completely resolved.

Conclusions

The pathophysiological mechanism underlying RPLS is still not well understood, which makes it difficult to explain the unilateral appearance in this case. Since the imaging findings may be confused with other conditions such as ischemia, recognition of RPLS after coiling is necessary in order to avoid inadequate treatment.  相似文献   
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OBJECTIVE: To search for novel genes contributing to adiposity in familial combined hyperlipidemia (FCH), a disorder characterized by abdominal obesity, hyperlipidemia and insulin resistance, using a 10cM genome-wide scan. DESIGN: Plasma leptin and soluble tumor necrosis factor receptor superfamily members 1A and 1B (sTNFRSF1A and sTNFRSF1B, also known as sTNFR1 and sTNFR2) were analyzed as unadjusted and adjusted quantitative phenotypes of adiposity, in addition to body mass index (BMI), in multipoint and single-point analyses. In the second stage of analysis, an important chromosome 1 positional candidate gene, the leptin receptor (LEPR), was studied. SUBJECTS: Eighteen Dutch pedigrees with familial combined hyperlipidemia (FCH) (n= 198) were analyzed to search for chromosomal regions harboring genes contributing to adiposity. RESULTS: Multipoint analysis of the genome scan data identified linkage (log of odds, LOD, 3.4) of leptin levels to a chromosomal region defined by D1S3728 and D1S1665, flanking the leptin receptor (LEPR) gene by approximately 9 and 3 cM, respectively. The LOD score decreased to 1.8 with age- and gender-adjusted leptin levels. Notably, BMI also mapped to this region with an LOD score of 1.2 (adjusted BMI: LOD 0.5). Two polymorphic DNA markers in LEPR and their haplotypes revealed linkage to unadjusted and adjusted BMI and leptin, and an association with leptin levels was found as well. In addition, the marker D8S1110 showed linkage (LOD 2.8) with unadjusted plasma concentrations of soluble TNFRSF1A. BMI gave a LOD score of 0.6. Moreover, a chromosome 10 q-ter locus, AFM198ZB, showed linkage with adjusted BMI (LOD 3.3). CONCLUSION: These data provide evidence that a human chromosome 1 locus, harboring the LEPR gene, contributes to plasma leptin concentrations, adiposity and body weight in humans affected with this insulin resistant dyslipidemic syndrome. Novel loci on chromosome 8 and 10 qter need further study.  相似文献   
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This paper critically reviews the reported relationships between malnutrition and learning. Since malnutrition is not randomly distributed in the social system, the relationships between malnutrition and intellectual development are often confounded by the relationship between social class and malnutrition. The psychological consequences of malnutrition which have been reported are similar to those for social isolation among infants, and isolation may be a confounding factor in the development of infants hospitalized for malnutrition. The older malnourished child may be cut off from important learning opportunities, both by lack of energy to pay attention to these opportunities and by living in settings in which the opportunities do not exist. He may acquire a self concept and be responded to by others in ways which further inhibit his development. While few data exist on the effects of hunger, they may be similar to those of malnutrition. In addition, because those who are hungry are stigmatized, others may treat the child labeled “hungry” in ways which prevent his adequate social and psychological development.  相似文献   
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Aims/hypothesis

The hyperglycaemic clamp technique and the frequently sampled IVGTT are unsuitable techniques to assess beta cell function (BCF) in large cohorts. Therefore, the aim of this study was to evaluate the discriminatory ability of simple OGTT-based BCF indices for prediction of prediabetes (meaning impaired fasting glucose and/or impaired glucose tolerance) and type 2 diabetes.

Methods

Glucose metabolism status was assessed by 2 h 75 g OGTT at baseline (n?=?476, mean age 59.2 years, 38.7% women) and after 7 years of follow-up (n?=?416) in the Cohort on Diabetes and Atherosclerosis Maastricht (CODAM) study (1999–2009). Baseline plasma glucose, insulin and C-peptide values during OGTTs were used to calculate 21 simple indices of BCF. Disposition indices (BCF index × Matsuda index), to compensate for the prevailing level of insulin resistance, were calculated for the BCF indices with the best discriminatory abilities. The discriminatory ability of the BCF indices was estimated by the area under the receiver operating characteristics curve (ROC AUC) with an outcome of incident prediabetes (n?=?73) or type 2 diabetes (n?=?60 and n?=?18 cases, respectively, in individuals who were non-diabetic or had normal glucose metabolism at baseline).

Results

For incident prediabetes (n?=?73), all ROC AUCs were less than 70%, whereas for incident type 2 diabetes, I30/I0, CP30/CP0, ΔI30/ΔG30, ΔCP30/ΔG30 (where I, CP and G are the plasma concentrations of insulin, C-peptide and glucose, respectively, at the times indicated), and corrected insulin response at 30 min had ROC AUCs over 70%. In at-baseline non-diabetic individuals, disposition indices ΔI30/ΔG30, ΔCP30/ΔG30 and corrected insulin response at 30 min had ROC AUCs of over 80% for incident type 2 diabetes. Moreover, these BCF disposition indices had significantly better discriminatory abilities for incident type 2 diabetes than the Matsuda index alone.

Conclusions/interpretation

BCF indices reflecting early-phase insulin secretion have the best ability to discriminate individuals who will develop prediabetes and type 2 diabetes. Of these, ΔCP30/ΔG30, often referred to as the C-peptidogenic index, performed consistently well.
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