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Objective

An unclear issue is whether gender may influence at cardiac remodeling after myocardial infarction (MI). We evaluated left ventricle remodeling in female and male rats post-MI.

Methods

Rats were submitted to anterior descending coronary occlusion. Echocardiographic evaluations were performed on the first and sixth week post-occlusion to determine myocardial infarction size and left ventricle systolic function (FAC, fractional area change). Pulsed Doppler was applied to analyze left ventricle diastolic function using the following parameters: E wave, A wave, E/A ratio. Two-way ANOVA was applied for comparisons, complemented by the Bonferroni test. A P≤=0.05 was considered significant.

Results

There were no significant differences between genders for morphometric parameters on first (MI [Female (FE): 44.0±5.0 vs. Male (MA): 42.0±3.0%]; diastolic [FE: 0.04±0.003 vs. MA: 0.037±0.005, mm/g] and systolic [FE: 0.03±0.0004 vs. MA: 0.028±0.005, mm/g] diameters of left ventricle) and sixth (MI [FE: 44.0±5.0 vs. MA: 42.0±3.0, %]; diastolic [FE: 0.043±0.01 vs. MA: 0.034±0.005, mm/g] and systolic [FE: 0.035±0.01 vs. MA: 0.027±0.005, mm/g] of LV) week. Similar findings were reported for left ventricle functional parameters on first (FAC [FE: 34.0±6.0 vs. MA: 32.0±4.0, %]; wave E [FE: 70.0±18.0 vs. MA: 73.0±14.0, cm/s]; wave A [FE: 20.0±12.0 vs. MA: 28.0±13.0, cm/s]; E/A [FE: 4.9±3.4 vs. MA: 3.3±1.8]) and sixth (FAC [FE: 29.0±7.0 vs. MA: 31.0±7.0, %]; wave E [FE: 85.0±18.0 vs. MA: 87.0±20.0, cm/s]; wave A [FE: 20.0±11.0 vs. MA: 28.0±17.0, cm/s]; E/A [FE: 6.2±4.0 vs. MA: 4.6±3.4]) week.

Conclusion

Gender does not influence left ventricle remodeling post-MI in rats.  相似文献   
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Impaired amyloid beta (Aβ) metabolism is currently considered central to understand the pathophysiology of Alzheimer's disease (AD). Measurements of cerebrospinal fluid Aβ levels remain the most useful marker for diagnostic purposes and to individuate people at risk for AD. Despite recent advances criticized the direct role in neurodegeneration of cortical neurons, Aβ is considered responsible for synaptopathy and impairment of neurotransmission and therefore remains the major trigger of AD and future pharmacological treatment remain Aβ oriented. However, experimental and clinical findings showed that Aβ peptides could have a wider range of action responsible for cell dysfunction and for appearance of clinico‐pathological entities different from AD. Such findings may induce misunderstanding of the real role played by Aβ in AD and therefore strengthen criticism on its centrality and need for CSF measurements. Aim of this review is to discuss the role of CSF Aβ levels in light of experimental, clinical pathologic, and electrophysiological results in AD and other pathological entities to put in a correct frame the value of Aβ changes.  相似文献   
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[Purpose] This study investigated the effects of postural angle on back muscle activity during a computer task in aging women. [Subjects] Seventeen women ≥50 years old participated. [Methods] The participants were instructed to perform computer-related tasks for 20 minutes on a workstation that simulated typical office working conditions. Back posture was measured from the measured trunk and pelvic angles. Electromyography activities were recorded simultaneously from the cervical erector spinae, longissimus, and multifidus muscles. [Results] The lowest mean percentages of maximum voluntary contraction for the cervical erector spinae and longissimus muscles were obtained when the upper trunk and pelvic angles were between 0° to −5° from the sagittal plane. The back muscle activities increased as the upper trunk and pelvic angles exceeded 0°. Statistical analysis showed significant correlations between upper trunk angle and cervical erector spinae and longissimus muscle activities. Similarly, pelvic angle was significantly correlated with cervical erector spinae and multifidus muscle activities. [Conclusion] A neutral back posture minimizes muscle activities in aging women performing computer tasks.Key words: Postural angle, Muscle activity, Aging  相似文献   
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Introduction

This article seeks to identify where delays occur along the adult HIV care cascade (“the cascade”), to improve understanding of what constitutes “delay” at each stage of the cascade and how this can be measured across a range of settings and to inform service delivery efforts. Current metrics are reviewed, measures informed by global guidelines are suggested and areas for further clarification are underscored.

Discussion

Questions remain on how best to evaluate late entry into each stage of the cascade. The delayed uptake of HIV testing may be more consistently measured once rapid CD4 testing is administered at the time of HIV testing. For late enrolment, preliminary research has begun to determine how different time intervals for linking to HIV care affect individual health. Regarding treatment, since 2013, the World Health Organization (WHO) and UNAIDS recommend treatment initiation when CD4 <500 cells/mm3; these guidelines provide a useful albeit evolving threshold to define late treatment initiation. Finally, WHO guidelines for high-, low- and middle-income countries also could be used to standardize measures for achieving viral suppression.

Conclusions

There is no “one size fits all” model as the provision of services may differ based on a range of factors. Nonetheless, measures informed by global guidelines are needed to more consistently evaluate the scope of and factors associated with delays to each stage of the cascade. Doing so will help identify how practitioners can best deliver services and facilitate access to and continued engagement in care.  相似文献   
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