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101.
BackgroundMyotonic dystrophy type 1 (DM1) is a complex life-limiting neuromuscular disorder characterized by severe skeletal muscle atrophy, weakness, and cardiorespiratory defects. Exercised DM1 mice exhibit numerous physiological benefits that are underpinned by reduced CUG foci and improved alternative splicing. However, the efficacy of physical activity in patients is unknown.MethodsEleven genetically diagnosed DM1 patients were recruited to examine the extent to which 12 weeks of cycling can recuperate clinical and physiological metrics. Furthermore, we studied the underlying molecular mechanisms through which exercise elicits benefits in skeletal muscle of DM1 patients.RESULTSDM1 was associated with impaired muscle function, fitness, and lung capacity. Cycling evoked several clinical, physical, and metabolic advantages in DM1 patients. We highlight that exercise-induced molecular and cellular alterations in patients do not conform with previously published data in murine models and propose a significant role of mitochondrial function in DM1 pathology. Finally, we discovered a subset of small nucleolar RNAs (snoRNAs) that correlated to indicators of disease severity.ConclusionWith no available cures, our data support the efficacy of exercise as a primary intervention to partially mitigate the clinical progression of DM1. Additionally, we provide evidence for the involvement of snoRNAs and other noncoding RNAs in DM1 pathophysiology.Trial registrationThis trial was approved by the HiREB committee (no. 7901) and registered under ClinicalTrials.gov (NCT04187482).FundingNeil and Leanne Petroff. Canadian Institutes of Health Research Foundation (no. 143325).  相似文献   
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Stearns V  Beebe KL  Iyengar M  Dube E 《JAMA》2003,289(21):2827-2834
Context  Standard therapy for hot flashes has been hormone replacement with estradiol or progestational agents, but recent data suggest that antidepressants inhibiting serotonin reuptake may also be effective. Objective  To evaluate a selective serotonin reuptake inhibitor (paroxetine controlled release [CR]) in treating the vasomotor symptoms displayed by a general cross-section of menopausal women. Design and Setting  Randomized, double-blind, placebo-controlled, parallel group study conducted across 17 US sites, including urban, suburban, and rural clinics. Patients  A total of 165 menopausal women aged 18 years or older experiencing at least 2 to 3 daily hot flashes and must have discontinued any hormone replacement therapy for at least 6 weeks. Women were excluded if they had any signs of active cancer or were undergoing chemotherapy or radiation therapy. Intervention  After a 1-week placebo run-in phase, study participants were randomized to receive placebo or receive 12.5 mg/d or 25.0 mg/d of paroxetine CR (in a 1:1:1 ratio) for 6 weeks. Main Outcome Measures  Mean change from baseline to week 6 in the daily hot flash composite score (frequency x severity). Results  Fifty-six participants were randomly assigned to receive placebo and 51 to receive 12.5 mg/d and 58 to receive 25.0 mg/d of paroxetine CR. The mean reductions in the hot flash frequency composite score from baseline to week 6 were statistically significantly greater for those receiving paroxetine CR than for those receiving placebo. By week 6, the mean daily hot flash frequency went from 7.1 to 3.8 (mean reduction, 3.3) for those in the 12.5-mg/d and from 6.4 to 3.2 (mean reduction, 3.2) for those in the 25-mg/d paroxetine CR groups and from 6.6 to 4.8 (mean reduction, 1.8) for those in the placebo group. Mean placebo-adjusted reduction in hot flash composite scores were -4.7 (95% confidence interval, - 8.1 to -1.3; P = .007) comparing 12.5-mg/d paroxetine CR with placebo; and -3.6 (95% confidence interval, -6.8 to -0.4; P = .03) comparing 25.0-mg/d paroxetine CR with placebo. This corresponded to median reductions of 62.2% for those in the 12.5-mg/d and 64.6% for those in the 25.0-mg/d paroxetine CR groups compared with 37.8% for those in the placebo group. Conclusion  Paroxetine CR may be an effective and acceptable alternative to hormone replacement and other therapies in treating menopausal hot flash symptoms.   相似文献   
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A number of small-molecule poly (ADP-ribose) polymerase (PARP) inhibitors are currently undergoing advanced clinical trials. Determining the distribution and target inhibitory activity of these drugs in individual subjects, however, has proven problematic. Here, we used a PARP agent for positron emission tomography-computed tomography (PET-CT) imaging (18F-BO), which we developed based on the Olaparib scaffold using rapid bioorthogonal conjugation chemistries. We show that the bioorthogonal 18F modification of the parent molecule is simple, highly efficient, and well tolerated, resulting in a half maximal inhibitory concentration (IC50) of 17.9 ± 1.1 nM. Intravital imaging showed ubiquitous distribution of the drug and uptake into cancer cells, with ultimate localization within the nucleus, all of which were inhibitable. Whole-body PET-CT imaging showed tumoral uptake of the drug, which decreased significantly, after a daily dose of Olaparib. Standard 18F-fludeoxyglucose imaging, however, failed to detect such therapy-induced changes. This research represents a step toward developing a more generic approach for the rapid codevelopment of companion imaging agents based on small-molecule therapeutic inhibitors.  相似文献   
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Physical activity in early midlife has important implications for women's health. The present cross-sectional study investigated the relation of purposiveness to leisure-time physical activity, as mediated by health investment, in a sample of women in early midlife. Participants were 211 women between the ages of 35 and 45 years (mean 40.55 years, SD = 3.11) who responded to the second wave of the study of Midlife Development in the United States. Participants were originally selected by means of a nationally representative random-digit-dialing procedure. A structural equation analysis of data with latent variables was conducted with MPLUS. Purposiveness was indexed by measures of purpose in life, personal growth, and future planning. Health investment was indexed by thought and effort committed to health and the extent to which individuals worked hard to stay healthy. Leisure-time physical activity was indexed by both moderate and vigorous leisure-time activity. Results, controlling for sociodemographic factors, showed that purposiveness was associated with more physical activity and that the relation between purposiveness and leisure-time physical activity was fully mediated by health investment. These results suggest that women with a sense of purpose may be better able to achieve acceptable levels of physical activity.  相似文献   
107.
Leaves of the tropical tree Moringa oleifera are widely promoted in areas of chronic malnutrition as nutritional supplements for weaning infants and nursing mothers. Adoption, in these circumstances may hinge upon taste, which can vary greatly amongst cultivars. It is widely assumed that this taste variation is primarily germplasm-dependent, and results from the breakdown of glucosinolates to isothiocyanates. Leaves of 30 accessions, grown at a single field plot, were sampled 3 times over the course of a year. Taste, assessed in a masked protocol, was not related to glucosinolate content of the leaves.  相似文献   
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