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101.
Abstract

The cerebral control of bimanual movements is not completely understood. We investigated a 59-year-old, right-handed man who presented with an acute bimanual coordination deficit. Magnetic resonance imaging showed a lesion involving the entire corpus callosum, which was found on stereotactic biopsy to be an ischemic infarct. Paired-pulse transcranial magnetic stimulation indicated that the patient had a lack of interhemispheric inhibition, while intracortical inhibition in motor cortex of either side was normal. Functional magnetic resonance imaging showed activation of the left SMA, the bilateral motor cortex and anterior cerebellum during spontaneous bimanual thumb-index oppositions, which were uncoupled as evident from simultaneous electromyographic recordings. In contrast, when the bimanual thumb-index oppositions were cued by a visual stimulus, the movements of both hands were tightly correlated. This synchronized activity was accompanied by additional activations bilateral in lateral occipital cortex, dorsal premotor cortex and cerebellum. The data suggest that the visually cued movements of both hands were recoupled by action of a bihemispheric motor network.  相似文献   
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Aim: To identify predictors of negative in‐patient outcomes (prolonged hospital stay and death) in nursing home (NH) residents admitted to the hospital as medical emergencies. Methods: This was a retrospective patient series set at St James's Hospital (Dublin, Ireland). The participants were all NH patients requiring acute medical admission under the on‐call medical team between 1 January 2002 and 31 December 2010. Patient characteristics on admission, such as demographics, comorbidity level, major diagnostic categories, vital signs and laboratory profile, were measured. The outcomes of the study were prolonged hospital stay (≥30 days) and in‐hospital mortality. The characteristics of NH patients were compared with those of non‐NH patients aged ≥65 years. Multivariate analyses were based on generalized estimating equations and classification trees. Results: There were 55 763 acute medical admissions over the period, of which 1938 (3.5%) were from NH. As compared with non‐NH patients aged ≥65 years, NH patients had greater acute illness severity. NH patients had a median length of stay of 7 days, and 17% had a prolonged admission. Their overall mortality rate was 23%. However, the classification analysis showed substantial patient heterogeneity; the subgroup with the highest mortality (54%, n = 100) had positive serum troponin and a respiratory major diagnosis. The lowest mortality rate (4%) was seen in those without positive troponin, urea of 12 mmol/L or less, and albumin of more than 37 mg/L (n = 226). Conclusions: Simple serum markers, such as troponin, urea and albumin, might predict mortality in medically admitted NH patients. This might help health‐care practitioners to anticipate their clinical course at an early stage. Geriatr Gerontol Int 2012; ??: ??–??.  相似文献   
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?2012 Wiley Periodicals, Inc. Anthracycline treatments are hampered by dose-related cardiotoxicity, frequently leading to heart failure (HF) with a very poor prognosis. The authors report a case of a 19-year-old man developing HF after anthracycline treatment for Ewing sarcoma. Despite medical treatment, his condition deteriorated to terminal HF, leading to implantation of a mechanical left ventricular assist device (LVAD). His heart function recovered, allowing explantation of the device 14?months after implantation. Heart transplantation is often contraindicated in the first years after treatment for cancers, and LVAD as "bridge to recovery" may be warranted in similar patients.  相似文献   
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Purpose

Insulin is a commonly used additive in chondrogenic media for differentiating mesenchymal stem cells (MSCs). The indispensability of other bioactive factors like TGF-β or dexamethasone in these medium formulations has been shown, but the role of insulin is unclear. The purpose of this study was to investigate whether insulin is essential for MSC chondrogenesis and if there is a dose-dependent effect of insulin on MSC chondrogenesis.

Methods

We cultivated human MSCs in pellet culture in serum-free chondrogenic medium with insulin concentrations between 0 and 50 μg/ml and assessed the grade of chondrogenic differentiation by histological evaluation and determination of glycosaminoglycan (GAG), total collagen and DNA content. We further tested whether insulin can be delivered in an amount sufficient for MSC chondrogenesis via a drug delivery system in insulin-free medium.

Results

Chondrogenesis was not induced by standard chondrogenic medium without insulin and the expression of cartilage differentiation markers was dose-dependent at insulin concentrations between 0 and 10 μg/ml. An insulin concentration of 50 μg/ml had no additional effect compared with 10 μg/ml. Insulin was delivered by a release system into the cell culture under insulin-free conditions in an amount sufficient to induce chondrogenesis.

Conclusions

Insulin is essential for MSC chondrogenesis in this system and chondrogenic differentiation is influenced by insulin in a dose-dependent manner. Insulin can be provided in a sufficient amount by a drug delivery system. Therefore, insulin is a suitable and inexpensive indicator substance for testing drug release systems in vitro.  相似文献   
109.

Background

The Weight Loss Maintenance Trial tested strategies for maintenance of weight loss. Personal contact was superior to interactive technology and self-directed conditions.

Purpose

We aimed to identify behavioral mediators of the superior effect of personal contact vs. interactive technology and of personal contact vs. self-directed arms.

Methods

Overweight/obese adults at risk for cardiovascular disease (n?=?1,032) who lost at least 4 kg were randomized to personal contact, interactive technology, or self-directed. After 30 months, 880 participants had data on weight and behavioral strategies.

Results

Reported increase of intake of fruits and vegetables and physical activity and more frequent self-weighing met criteria as mediators of the better outcome of personal contact vs. interactive technology. Increased intake of fruits and vegetables, more frequent self-weighing, and decreased dessert consumption were mediators of the difference between personal contact vs. self-directed.

Conclusion

Inducing changes in the identified behaviors might yield better outcomes in future weight loss maintenance trials. (ClinicalTrials.gov number NCT00054925)  相似文献   
110.
As marijuana (MJ) legalization is increasing, kidney transplant programs must develop listing criteria for marijuana users. However, no data exist on the effect of MJ on kidney allograft outcomes, and there is no consensus on whether MJ use should be a contraindication to transplantation. We retrospectively reviewed 1225 kidney recipients from 2008 to 2013. Marijuana use was defined by positive urine toxicology screen and/or self‐reported recent use. The primary outcome was death at 1 year or graft failure (defined as GFR<20 mL/min/1.73 m2). The secondary outcome was graft function at 1 year. Using logistic regression analyses, we compared these outcomes between MJ users and non‐users. Marijuana use was not associated with worse primary outcomes by unadjusted (odds ratio 1.07, 95% CI 0.45–2.57, P=.87) or adjusted (odds ratio 0.79, 95% CI 0.28–2.28, P=.67) analysis. Ninety‐two percent of grafts functioned at 1 year. Among these, the mean creatinine (1.52, 95% CI 1.39–1.69 vs 1.46, 95% CI 1.42–1.49; P=.38) and MDRD GFR (50.7, 95% CI 45.6–56.5 vs 49.5, 95% CI 48.3–50.7; P=.65) were similar between groups. Isolated recreational MJ use is not associated with poorer patient or kidney allograft outcomes at 1 year. Therefore, recreational MJ use should not necessarily be considered a contraindication to kidney transplantation.  相似文献   
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