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1.
Objectives: Amnestic mild cognitive impairment (aMCI) often corresponds to the prodromal stage of Alzheimer disease (AD). The aMCI stage represents a crucial time window to apply preventive interventions in an attempt to delay cognitive decline. Stress, one of AD’s modifiable risk factors frequently co-occurring with aMCI, stands out as a key intervention target. The goal of this study was to assess the impacts of two non-pharmacological interventions, mindfulness and psychoeducation, on stress at the psychological and physiological levels among aMCI older adults.

Methods: Forty-eight aMCI participants were randomized between a mindfulness-based intervention (MBI) and a psychoeducation-based intervention (PBI) for eight weekly sessions. Anxiety symptoms, perceived stress levels, cortisol awakening response (CAR), and coping strategies were assessed pre- and post-intervention. Mindfulness attitudes and time dedicated to at-home meditative practices were evaluated in the MBI group.

Results: The main results revealed a slight reduction of the CAR among MBI participants who practiced meditation at home the most and a decrease in perceived stress levels in the PBI group. Both interventions enhanced problem-focused coping strategies.

Conclusion: In sum, this pilot study supports the potential of MBI and PBI to reduce stress at the physiological and psychological level, respectively, and increase coping strategies in older adults at risk for AD.  相似文献   

2.
Animal locomotion requires changing direction, from forward to backward. Here, we tested the hypothesis that sensorimotor circuits within the spinal cord generate backward locomotion and adjust it to task demands. We collected kinematic and electromyography (EMG) data during forward and backward locomotion at different treadmill speeds before and after complete spinal transection in six adult cats (three males and three females). After spinal transection, five/six cats performed backward locomotion, which required tonic somatosensory input in the form of perineal stimulation. One spinal cat performed forward locomotion but not backward locomotion while two others stepped backward but not forward. Spatiotemporal adjustments to increasing speed were similar in intact and spinal cats during backward locomotion and strategies were similar to forward locomotion, with shorter cycle and stance durations and longer stride lengths. Patterns of muscle activations, including muscle synergies, were similar for forward and backward locomotion in spinal cats. Indeed, we identified five muscle synergies that were similar during forward and backward locomotion. Lastly, spinal cats also stepped backward on a split-belt treadmill, with the left and right hindlimbs stepping at different speeds. Therefore, our results show that spinal sensorimotor circuits generate backward locomotion but require additional excitability compared with forward locomotion. Similar strategies for speed modulation and similar patterns of muscle activations and muscle synergies during forward and backward locomotion are consistent with a shared spinal locomotor network, with sensory feedback from the limbs controlling the direction.SIGNIFICANCE STATEMENT Animal locomotion requires changing direction, including forward, sideways and backward. This paper shows that the center controlling locomotion within the spinal cord can produce a backward pattern when instructed by sensory signals from the limbs. However, the spinal locomotor network requires greater excitability to produce backward locomotion compared with forward locomotion. The paper also shows that the spinal network controlling locomotion in the forward direction also controls locomotion in the backward direction.  相似文献   
3.
This article reviews the most common gynecologic malignancies and their MR imaging features. The overall goal remains early disease detection and accurate staging to optimize treatment and thereby to reduce morbidity and mortality. MR imaging, when available, may play an important role in the accurate staging and evaluation of female pelvic malignancies and, thus, may become part of their routine investigation. In the authors' experience, MR imaging has proven useful in the preoperative evaluation of these malignancies. With ongoing research into imaging protocols designed to improve image quality and reduce examination time, the importance of MR imaging will continue to grow.  相似文献   
4.

Background

Hepatocellular carcinoma (HCC) is an indication for liver resection or transplantation (LT). In most centers, patients whose HCC meets the Milan criteria are considered for LT. The first objective of this study was to analyze whether there is a correlation between the pathologic characteristics of the tumor, survival and recurrence rate. Second, we focused our attention on vascular invasion (VI).

Methods

From January 1997 to December 2007, a total of 196 patients who had a preoperative diagnosis of HCC were included. The selection criteria for LT satisfied both the Milan and the San Francisco criteria (UCSF). Demographic, clinical, and pathologic information were recorded.

Results

HCC was confirmed in 168 patients (85.7%). The median follow-up was 74?months. The pathologic findings showed that 106 patients (54.1%) satisfied the Milan criteria, 134 (68.4%) the UCSF criteria of whom 28 (14.3%) were beyond the Milan criteria but within the UCSF criteria, and 34 (17.3%) beyond the UCSF criteria. VI was detected in 41 patients (24%). The 1-, 3-, and 5-year overall survival rates were 90%, 85%, and 77%, respectively, according to the Milan criteria and 90%, 83%, and 76%, respectively, according to the UCSF criteria (P?=?NS). In univariate and multivariate analyses, tumor size and VI were significant prognostic factors affecting survival (P?400?ng/ml and tumor grade G3.

Conclusions

Tumor size and VI were the only significant prognostic factors affecting survival of HCC patients. Primary liver resection could be a potential selection treatment before LT.  相似文献   
5.
6.
BACKGROUND. Ebola virus (EBOV) causes periodic outbreaks of life-threatening EBOV disease in Africa. Historically, these outbreaks have been relatively small and geographically contained; however, the magnitude of the EBOV outbreak that began in 2014 in West Africa has been unprecedented. The aim of this study was to describe the viral kinetics of EBOV during this outbreak and identify factors that contribute to outbreak progression.METHODS. From July to December 2014, one laboratory in Sierra Leone processed over 2,700 patient samples for EBOV detection by quantitative PCR (qPCR). Viremia was measured following patient admission. Age, sex, and approximate time of symptom onset were also recorded for each patient. The data was analyzed using various mathematical models to find trends of potential interest.RESULTS. The analysis revealed a significant difference (P = 2.7 × 10–77) between the initial viremia of survivors (4.02 log10 genome equivalents [GEQ]/ml) and nonsurvivors (6.18 log10 GEQ/ml). At the population level, patient viral loads were higher on average in July than in November, even when accounting for outcome and time since onset of symptoms. This decrease in viral loads temporally correlated with an increase in circulating EBOV-specific IgG antibodies among individuals who were suspected of being infected but shown to be negative for the virus by PCR.CONCLUSIONS. Our results indicate that initial viremia is associated with outcome of the individual and outbreak duration; therefore, care must be taken in planning clinical trials and interventions. Additional research in virus adaptation and the impacts of host factors on EBOV transmission and pathogenesis is needed.  相似文献   
7.

Objective

To examine the relationship between community factors and hospital readmission rates.

Data Sources/Study Setting

We examined all hospitals with publicly reported 30-day readmission rates for patients discharged during July 1, 2007, to June 30, 2010, with acute myocardial infarction (AMI), heart failure (HF), or pneumonia (PN). We linked these to publicly available county data from the Area Resource File, the Census, Nursing Home Compare, and the Neilsen PopFacts datasets.

Study Design

We used hierarchical linear models to assess the effect of county demographic, access to care, and nursing home quality characteristics on the pooled 30-day risk-standardized readmission rate.

Data Collection/Extraction Methods

Not applicable.

Principal Findings

The study sample included 4,073 hospitals. Fifty-eight percent of national variation in hospital readmission rates was explained by the county in which the hospital was located. In multivariable analysis, a number of county characteristics were found to be independently associated with higher readmission rates, the strongest associations being for measures of access to care. These county characteristics explained almost half of the total variation across counties.

Conclusions

Community factors, as measured by county characteristics, explain a substantial amount of variation in hospital readmission rates.  相似文献   
8.
No diel variations of plasma cortisol levels were found in Gasterosteus aculeatus acclimated to two different photoperiod conditions: 14L:10D and 9L:15D. However, under long photoperiods, G. aculeatus exhibited higher plasma cortisol levels than under short photoperiods, suggesting that elevated plasma cortisol levels are associated with the spring migration and/or reproductive activities. This decrease of plasma cortisol levels is particularly marked in male G. aculeatus. Under the 9L:15D photoperiod, males had lower plasma cortisol levels than females, in contrast to 14L:10D, where no significant sex differences were found.  相似文献   
9.
Waning immunity or secondary vaccine failure (SVF) has been anticipated by some as a challenge to global measles elimination efforts. Although such cases are infrequent, measles virus (MeV) infection can occur in vaccinated individuals following intense and/or prolonged exposure to an infected individual and may present as a modified illness that is unrecognizable as measles outside of the context of a measles outbreak. The immunoglobulin M response in previously vaccinated individuals may be nominal or fleeting, and viral replication may be limited. As global elimination proceeds, additional methods for confirming modified measles cases may be needed to understand whether SVF cases contribute to continued measles virus (MeV) transmission. In this report, we describe clinical symptoms and laboratory results for unvaccinated individuals with acute measles and individuals with SVF identified during MeV outbreaks. SVF cases were characterized by the serological parameters of high-avidity antibodies and distinctively high levels of neutralizing antibody. These parameters may represent useful biomarkers for classification of SVF cases that previously could not be confirmed as such using routine laboratory diagnostic techniques.  相似文献   
10.
M. Audet, T. Piardi, F. Panaro, E. Ghislotti, F. Gheza, M. Cag, T.M. Jarzembowski, H. Flicoteaux, P. Wolf, J. Cinqualbre. Incidence and clinical significance of bacterial and fungal contamination of the preservation solution in liver transplantation.
Transpl Infect Dis 2011: 13: 84–88. All rights reserved Abstract: A perfusion fluid used in the preservation of the grafted liver represents a medium suitable for microorganism growth. In this observational study, a sample of 232 transplanted livers was collected. Perfusion fluid samples were stored for microbiological analysis from harvested donors. Bacteria were isolated in 91 out of 232 samples, post‐operative infections related to contaminated perfusion solution occurred in 13 cases. The contamination rate of the preservation medium appears to be high, but postoperative infections occurs rarely. We suggest periodic detection and a protocol in place designed for antibiotic use for transplanted patients exposed to contaminated perfusion solution.  相似文献   
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