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The current study was designed to further clarify the influence of brain morphology, sleep oscillatory activity and age on memory consolidation. Specifically, we hypothesized, that a smaller volume of hippocampus, parahippocampal and medial prefrontal cortex negatively impacts declarative, but not procedural, memory consolidation. Explorative analyses were conducted to demonstrate whether a decrease in slow‐wave activity negatively impacts declarative memory consolidation, and whether these factors mediate age effects on memory consolidation. Thirty‐eight healthy participants underwent an acquisition session in the evening and a retrieval session in the morning after night‐time sleep with polysomnographic monitoring. Declarative memory was assessed with the paired‐associate word list task, while procedural memory was tested using the mirror‐tracing task. All participants underwent high‐resolution magnetic resonance imaging. Participants with smaller hippocampal, parahippocampal and medial prefrontal cortex volumes displayed a reduced overnight declarative, but not procedural memory consolidation. Mediation analyses showed significant age effects on overnight declarative memory consolidation, but no significant mediation effects of brain morphology on this association. Further mediation analyses showed that the effects of age and brain morphology on overnight declarative memory consolidation were not mediated by polysomnographic variables or sleep electroencephalogram spectral power variables. Thus, the results suggest that the association between age, specific brain area volume and overnight memory consolidation is highly relevant, but does not necessarily depend on slow‐wave sleep as previously conceptualized.  相似文献   
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Multiple risk factors for rheumatoid arthritis (RA) have been studied, but there is a dearth of research on occupational noise, which is highly prevalent in the United States (U.S.). This study aimed to determine whether occupational noise exposure was associated with an elevated risk of prevalent RA in the U.S. general population. Data from the 2011 to 2012 cross-sectional, population-based National Health and Nutrition Examination Survey were used for secondary analysis. Self-reported lifetime exposure to very loud noise was linked to self-reported doctor-diagnosed RA in a sample of 4192 participants. Weighted logistic regression was used to obtain nationally representative prevalence odds ratios (OR). The main and fully adjusted models yielded OR = 3.98 (95% CI: 1.74, 9.11) and OR = 2.84 (95% CI: 1.23, 6.57) for participants exposed for ≥ 15 years compared to never exposed participants. Excluding those diagnosed with RA more than five years before the interview, the effect dropped to OR = 3.67 (95% CI: 1.06, 12.75) in the main model, and was no longer significant in the fully adjusted model (OR = 2.68, 95% CI: 0.80, 8.96). The only significant effect modifier was race/ethnicity, with higher risk in Non-Hispanic whites. To conclude, long-term occupational noise exposure might be a modifiable risk factor for RA, but currently, the evidence base is very thin and tenuous.  相似文献   
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The heavy chain 1 of cytoplasmic dynein (DYNC1H1) is responsible for movement of the motor complex along microtubules and recruitment of dynein components. Mutations in DYNC1H1 are associated with spinal muscular atrophy (SMA), hereditary motor and sensory neuropathy (HMSN), cortical malformations, or a combination of these. Combining linkage analysis and whole‐exome sequencing, we identified a novel dominant defect in the DYNC1H1 tail domain (c.1792C>T, p.Arg598Cys) causing axonal HMSN. Mutation analysis of the tail region in 355 patients identified a de novo mutation (c.791G>T, p.Arg264Leu) in an isolated SMA patient. Her phenotype was more severe than previously described, characterized by multiple congenital contractures and delayed motor milestones, without brain malformations. The mutations in DYNC1H1 increase the interaction with its adaptor BICD2. This relates to previous studies on BICD2 mutations causing a highly similar phenotype. Our findings broaden the genetic heterogeneity and refine the clinical spectrum of DYNC1H1, and have implications for molecular diagnostics of motor neuron diseases.  相似文献   
17.

Background

Poststroke distal lower limb spasticity impairs mobility, limiting activities of daily living and requiring additional caregiver time.

Objective

To evaluate the efficacy, safety, and sustained benefit of onabotulinumtoxinA in adults with poststroke lower limb spasticity (PSLLS).

Design

A multicenter, randomized, double-blind, phase 3, placebo-controlled trial (NCT01575054).

Setting

Sixty study centers across North America, Europe, Russia, the United Kingdom, and South Korea.

Patients

Adult patients (18-65 years of age) with PSLLS (Modified Ashworth Scale [MAS] ≥3) of the ankle plantar flexors and the most recent stroke ≥3 months before study enrollment.

Interventions

During the open-label phase, patients received ≤3 onabotulinumtoxinA treatments (≤400 U) or placebo at approximately 12-week intervals. Treatments were into the ankle plantar flexors (onabotulinumtoxinA 300 U into ankle plantar flexors; ≤100 U, optional lower limb muscles).

Main Outcome Measurements

The double-blind primary endpoint was MAS change from baseline (average score at weeks 4 and 6). Secondary measures included physician-assessed Clinical Global Impression of Change (CGI), MAS change from baseline in optional muscles, Goal Attainment Scale (GAS), and pain scale.

Results

Of 468 patients enrolled, 450 (96%) completed the double-blind phase and 413 (88%) completed the study. Small improvements in MAS observed with onabotulinumtoxinA during the double-blind phase (onabotulinumtoxinA, –0.8; placebo, –0.6, P = .01) were further enhanced with additional treatments through week 6 of the third open-label treatment cycle (onabotulinumtoxinA/onabotulinumtoxinA, –1.2; placebo/onabotulinumtoxinA, –1.4). Small improvements in CGI observed during the double-blind phase (onabotulinumtoxinA, 0.9; placebo, 0.7, P = .01) were also further enhanced through week 6 of the third open-label treatment cycle (onabotulinumtoxinA/onabotulinumtoxinA, 1.6; placebo/onabotulinumtoxinA, 1.6). Physician- and patient-assessed GAS scores improved with each subsequent treatment. No new safety signals emerged.

Conclusions

OnabotulinumtoxinA significantly improved ankle MAS, CGI, and GAS scores compared with placebo; improvements were consistent and increased with repeated treatments of onabotulinumtoxinA over 1 year in patients with PSLLS.

Level of Evidence

I  相似文献   
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Background

New preventive technologies such as vaccines offer insight into psychological, social, and cultural landscapes. Providers have a key role in parents' decisions for vaccinating their children. Yet, perspectives from providers regarding the human papillomavirus (HPV) vaccine, or vaccination in general, are rarely sought

Purpose

Our objective in this paper is to understand how the HPV vaccine is perceived by health care providers and the multiple contextual meanings it elicits.

Methods

We conducted interviews with 20 health care professionals in Bulgaria about their attitudes and practices related to HPV vaccination and their recommendations for policies. The verbatim-transcribed interviews were analyzed through narrative analysis, with a special focus on language.

Results

We illustrate providers' contradictory and contextualized constructions of the vaccine and the narrative strategies they use to manage any uncertainty it elicits. These include being advocates and missionaries for preventive health, confirming their trust in the medical profession and professional organizations, challenging patients' concerns with rational explanations, normalizing the risk of medical innovations, and avoiding the sexual nature of HPV transmission.

Conclusions

The introduction of a vaccine to prevent HPV infection, and by implication, possibly cervical and other cancers, created hope, and at the same time, intensified confusion and uncertainty. Providers have been frustrated for years with the rising mortality from cervical cancer in Bulgaria, and their perceived powerlessness in affecting this. HPV vaccination, on the other hand, seems relatively simple and “taming uncertainty” positions them as instrumental in limiting (or even eliminating) morbidity and mortality in future generations.  相似文献   
20.
Studies examining the prevalence of zoonotic agents in the Caribbean are very limited. The objective of this study was to examine the seroprevalence of seven zoonotic agents among individuals residing on 10 English-speaking Caribbean countries. Sera from healthy, pregnant women were collected from Antigua-Barbuda, Belize, Bermuda, Dominica, Grenada, Jamaica, Montserrat, St. Kitts-Nevis, St. Lucia, and St. Vincent-Grenadines and tested for the presence of IgG antibodies to dengue virus, hepatitis E virus, hantaviruses, leptospiral agents, spotted fever group rickettsiae (SFGR), typhus group rickettsiae (TGR), and Coxiella burnetii (Q fever). The highest seroprevalence values were observed for dengue virus, SFGR, and leptospirosis, although the lowest seroprevalence values were observed for hepatitis E virus, C. burnetii, and TGR. Antibodies to hantaviruses were not detected in any individuals.  相似文献   
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