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991.
A core feature of autism is the abnormal use of gaze to attribute mental states to others, and thus to predict others' behaviour. An untested idea is whether this dysfunction is confined to mental states having a propositional content, such as beliefs and desire or extends to motor intentional states which allow one to make inferences about the actions of others. This study used kinematics to examine the ability to use gaze to inform one about the motor states of another in normal and autistic children. In each trial two participants, a model and an observer, were seated facing each other at a table. In three experimental blocks the model was requested to grasp a stimulus, to gaze towards the same stimulus, and to gaze away from the stimulus without performing any action. The task for the observer was to grasp the stimulus after having watched the model perform her task. We observed that normal children showed facilitation effects in terms of movement speed following the observation of the model grasping or simply gazing at the object. In contrast, autistic children did not show any evidence of facilitation in these conditions. Neither normal nor autistic children showed evidence of facilitation when the model's gaze was not directed towards the stimulus. These findings demonstrate that, in contrast to normal children, children with autism fail to use information from the model's action or gaze to plan their subsequent action, and that in autism the inability to use of another person's gaze produces a lack of understanding of the motor intention of others.  相似文献   
992.
AIMS: This study assessed the impact of depression on mortality and quality of life of patients with kidney disease. MATERIAL: This study was conducted at Hospital S?o Lucas of Pontificia Universidade Católica of Rio Grande do Sul, Porto Alegre, Brazil, with a cohort of 125 patients seen from 1996 to 2004. (mean follow-up = 77.6 months). Patients undergoing renal replacement therapy were asked to fill in the Beck Depression Inventory (BDI). At the completion of follow-up, 72 patients were alive, and 56 answered the BDI and the Medical Outcome Study Short Form General Health Survey (SF-36) to assess quality of life. Main outcome measures were mortality and quality of life. RESULTS: Initial analysis showed that mortality was associated with age, treatment modality--continuous ambulatory peritoneal dialysis (CAPD) or hemodialysis (hd)--and depression. When controlling for age, gender, depression, and treatment modality in a multiple regression analysis, transplantation (tx), gender and age was associated with lower mortality. However, levels of depression at the end of follow-up were strongly associated with quality of life. CONCLUSIONS: Depression was not associated with mortality of patients with kidney disease when controlling for gender, age, and treatment modality. Transplantation was the main factor associated with lower mortality. Depression was, however, a strong predictor of quality of life. Number of depressive symptoms was directly associated with lower quality of life in most of the items of the SF-36.  相似文献   
993.
BACKGROUND: The purpose of this study was to compare an early behavioral intervention (EBI) with nonstructured standard physical care (routine care intervention [RCI]) in preventing antipsychotic-induced weight gain in drug-naive first-episode psychosis patients. METHOD: Sixty-one patients with a DSM-IV-diagnosed psychotic disorder were first randomly assigned to 3 different antipsychotic treatments (risperidone [N = 23], olanzapine [N = 18], and haloperidol [N = 21]) and subsequently randomly assigned to the intervention condition (EBI, N = 35) or RCI (N = 27). EBI was specifically designed to teach strategies to enhance control over factors associated with antipsychotic-induced weight gain and consisted of 8 flexible intervention modules that incorporated behavioral interventions, nutrition, and exercise. In the RCI group, patients were informed about potential weight gain and advised to increase their exercise and limit food intake. Body weight and body mass index were measured at baseline and then weekly for 3 months. In addition to change in weight and body mass index, a third outcome measure was the proportion of patients who had gained more than 7% of their body weight at 3 months. Participating patients were referred between August 2002 and September 2004. RESULTS: All 61 participants completed the study. Patients in the EBI group gained significantly less weight (mean = 4.1 kg, SD = 4.0) than those allocated to the RCI group (mean = 6.9 kg, SD = 4.5) (p < .01) during the 3-month follow-up period. Similar findings were obtained when both groups were compared on treatment-induced change in body mass index, which was significantly less in the EBI group than in the RCI group (1.40 vs. 2.39 kg/m2) (p < .01). Accordingly, significantly fewer patients in the EBI group (N = 11; 39.3%) than in the RCI group (N = 26; 78.8%) (p < .002) increased their baseline weight by more than 7%, the cutoff for clinically meaningful weight gain. CONCLUSIONS: EBI was effective in attenuating antipsychotic-induced weight gain in a drug-naive first-episode psychosis cohort. Patients displayed good adherence to this type of preventive intervention.  相似文献   
994.
995.

Background

Impairments in gluconeogenesis have been implicated in the pathophysiology of fasting hypoglycemia in medium-chain acyl-CoA dehydrogenase deficiency. However, whole body glucose and fat metabolism have never been studied in vivo.

Methods

Stable isotope methodology was applied to compare fat and glucose metabolism between four adult patients with MCADD and four matched controls both at rest and during 1.5 h of moderate-intensity exercise. Additionally, intramyocellular lipid and glycogen content and intramyocellular acylcarnitines were assessed in muscle biopsies collected prior to and immediately after cessation of exercise.

Results

At rest, plasma FFA turnover was significantly higher in patients with MCADD, whereas the plasma FFA concentrations did not differ between patients and controls. Blood glucose kinetics did not differ between groups both at rest and during exercise. Palmitate and FFA turnover, total fat and carbohydrate oxidation rates, the use of muscle glycogen and muscle derived triglycerides during exercise did not differ between patients and controls. Plasma FFA oxidation rates were significantly lower in patients at the latter stages of exercise. Free carnitine levels in muscle were lower in patients, whereas no differences were detected in muscle acetylcarnitine levels.

Conclusions

Whole-body or skeletal muscle glucose and fat metabolism were not impaired in adult patients with MCADD. This implies that MCADD is not rate limiting for energy production under the conditions studied. In addition, patients with MCADD have a higher FFA turnover rate after overnight fasting, which may stimulate ectopic lipid deposition and, as such, make them more susceptible for developing insulin resistance.  相似文献   
996.
With aging, an increased prevalence of a clustering of metabolic abnormalities has been observed. These abnormalities include obesity, dyslipidemia, hypertension, and insulin resistance and are collectively known as metabolic syndrome (MetS), a low-grade, systemic, inflammatory condition associated with an increased risk of cardiovascular disease, diabetes, and other adverse health outcomes. A number of studies have demonstrated that centenarians’ offspring have a significant survival advantage and a lower risk of developing the most important age-related diseases. They therefore represent one of the best models with which to study the familiar component of human longevity. The aim of this study was to determine if the offspring of centenarians (n = 265 subjects) showed a different prevalence of MetS in comparison to the offspring of non-long-lived parents (controls, n = 101 subjects). In addition, we assessed whether centenarians’ offspring showed particular features of MetS and a distinct regulation of circulating adipokines, cytokines, and metabolic mediators. Although the prevalence of MetS was quite similar both in the offspring of centenarians and the controls, MetS-affected centenarians’ offspring seemed healthier, more functionally fit, and had lower resistin levels. MetS prevalence did not change in centenarians’ offspring across resistin, IGF-1, and resistin/IGF-1 ratio tertiles. On the other hand, in controls, MetS prevalence strongly increased across resistin tertiles and in the third resistin/IGF-1 ratio tertile, indicating a dramatic increase in MetS prevalence when the ratio between these two factors is unbalanced, with high levels of resistin and low levels of IGF-1.  相似文献   
997.
998.
999.
The brain distribution of nonsteroidal aromatase inhibitors was investigated in mice to understand their interactions with brain aromatase. The brain-to-plasma ratio (Kp,brain, mL/g brain) of anastrozole was 0.0299 ± 0.0068, which was lower than that of letrozole (0.383 ± 0.048) and vorozole (0.185 ± 0.031) despite their similar physicochemical properties. The brain-to-plasma unbound concentration ratio of anastrozole, measured using microdialysis, was 0.118 ± 0.037 mL/g brain. In situ mouse brain perfusion also demonstrated that the uptake clearance [mL/(min·g brain)] of anastrozole by the brain (0.108 ± 0.018) was lower than that for letrozole and vorozole (0.422 ± 0.068 and 0.910 ± 0.152, respectively). Anastrozole and vorozole were transported by P-glycoprotein (P-gp) in vitro, whereas none of the compounds were transported by breast cancer resistance protein (BCRP). The Kp,brain of anastrozole and vorozole were increased by 12- and 3.3-fold, respectively, in Mdr1a/b/Bcrp(?/?) mice. IC50 (nM) of anastrozole and letrozole against human aromatase was 12.9 ± 0.7 and 3.59 ± 0.75, respectively. Taken together, these results suggest that active efflux mediated by P-gp at the blood–brain barrier limits the effect of anastrozole in the central nervous system, whereas vorozole and letrozole easily traverse the barrier.  相似文献   
1000.
Circulating tumor cells (CTC) harvested from peripheral blood have received significant interest as sources for serial sampling to gauge treatment efficacy. Nanotechnology and microfluidic based approaches are emerging to facilitate such analyses. While of considerable clinical importance, there is little information on how similar or different CTCs are from their shedding bulk tumors. In this clinical study, paired tumor fine needle aspirate and peripheral blood samples were obtained from cancer patients during image-guided biopsy. Using targeted magnetic nanoparticles and a point-of-care micro-NMR system, we compared selected biomarkers (EpCAM, EGFR, HER-2 and vimentin) in both CTC and fine needle biopsies of solid epithelial cancers. We show a weak correlation between each paired sample, suggesting that use of CTC as “liquid biopsies” and proxies to metastatic solid lesions could be misleading.From the Clinical EditorIn this clinical study, paired tumor fine needle aspirate and peripheral blood samples were obtained from patients with solid epithelial cancers during image-guided biopsy. Using targeted magnetic nanoparticles and a point-of-care micro-NMR system, the authors compared selected biomarkers in both circulating tumor cells (CTC) and fine needle biopsies, demonstrating a weak correlation between each paired sample, suggesting that use of CTC could be misleading in this context.  相似文献   
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