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11.

Background

The factors determining peak susceptibility of the developing brain to anaesthetics are unclear. It is unknown why postnatal day 7 (P7) male rats are more vulnerable to anaesthesia-induced memory deficits than littermate females. Given the precocious development of certain regions in the female brain during the neonatal critical period, we hypothesised that females are susceptible to anaesthetic brain injury at an earlier time point than previously tested.

Methods

Female rats were exposed to isoflurane (Iso) 1 minimum alveolar concentration or sham anaesthesia at P4 or P7. Starting at P35, rats underwent a series of behavioural tasks to test their spatial and recognition memory. Cell death immediately after anaesthesia was quantified by Fluoro-Jade C staining in select brain regions, and developmental expression of the chloride transporters KCC2 and NKCC1 was analysed by immunoblotting in male and female rats at P4 and P7.

Results

Female rats exposed to Iso at P4 displayed impaired spatial, object-place, -context, and social recognition memory, and increased cell death in the hippocampus and laterodorsal thalamus. Female rats exposed at P7 exhibited only decreased performance in object-context compared with control. The ratio of NKCC1/KCC2 expression in cerebral cortex was higher in P4 females than in P7 females, and similar to that in P7 males.

Conclusions

Female rats exposed to Iso at P4 are sensitive to anaesthetic injury historically observed in P7 males. This is consistent with a comparably immature developmental state in P4 females and P7 males. The window of anaesthetic vulnerability correlates with sex-specific cortical expression of chloride transporters NKCC1 and KCC2. These findings suggest that both sex and developmental age play important roles in determining the outcome after early anaesthesia exposure.  相似文献   
12.

Objectives

Arm swing is a distinctive characteristic of sprint-running with the arms working in a contralateral manner with the legs to propel the body in a horizontal direction. The purpose of this study was to determine the acute changes in kinematics and kinetics when wearable resistance (WR) of 1 kg (equivalent to ~1% body mass) was attached to each forearm during over ground short distance (20 m) maximal sprint-running.

Design

Cross-sectional study.

Methods

Twenty-two male amateur rugby athletes (19.4 ± 0.5 years; 97.0 ± 4.8 kg; 180.4 ± 7.2 cm) volunteered to participate in the study. Radar and Optojump were used to examine kinematic and kinetics between WR and unloaded sprint-running conditions.

Results

No significant (p < 0.05) differences were found at 2 m or 5 m between conditions, however, the WR condition resulted in a significant increase in 10 m, 20 m and 10–20 m split time (all, ~2%, small effect size) compared to the unloaded condition. Significant decreases were also found in theoretical maximum velocity (V0) (?1.4%, small effect size) and relative peak horizontal power production (Pmax) (?5.5%, small effect size). Step length (2.1%, small effect size) and contact time (6.5%, medium effect size) were significantly increased, while step frequency (?4.1%, small effect size) and flight time (?5.3%, medium effect size) were significantly decreased.

Conclusions

WR forearm loading provides a movement specific overload of the arms which significantly alters step kinematics and sprint times ≥10 m.  相似文献   
13.
Why do women live longer than men? Here, we mine rich lodes of demographic data to reveal that lower female mortality at particular ages is decisive—and that the important ages changed around 1950. Earlier, excess mortality among baby boys was crucial; afterward, the gap largely resulted from elevated mortality among men 60+. Young males bear modest responsibility for the sex gap in life expectancy: Depending on the country and time, their mortality accounts for less than a quarter and often less than a 10th of the gap. Understanding the impact on life expectancy of differences between male and female risks of death by age, over time, and across populations yields insights for research on how the lives of men and women differ.

Between ages 15 and 40, death rates for men are usually two or three times higher than death rates for women. This disparity has fueled widespread interest in the ratio of male to female death rates over the life course and in why it is exceptionally high for younger adults (16). Between ages 15 and 40, however, numbers of deaths are relatively low, so the high ratio of male to female death rates has a modest impact on the gap between female and male life expectancies. The sex difference in life expectancy hinges on differences in mortality risks at the ages when deaths are relatively common (7). Up through the early decades of the 20th century, these ages were at both extremes of life, infancy and old age. Afterward, death mostly struck after age 60. Here, we investigate variation across populations, over time, and over the life course in absolute and relative differences in mortality for men and women. We discuss what insights can be gained by scrutinizing relative risks compared to what can be learned by analyzing absolute risks.  相似文献   
14.
This study aimed to evaluate changes in sleep during the COVID‐19 outbreak, and used data‐driven approaches to identify distinct profiles of changes in sleep‐related behaviours. Demographic, behavioural and psychological factors associated with sleep changes were also investigated. An online population survey assessing sleep and mental health was distributed between 3 April and 24 June 2020. Retrospective questions were used to estimate temporal changes from before to during the outbreak. In 5,525 Canadian respondents (67.1% females, 16–95 years old: Mean ± SD = 55.6 ± 16.3 years), wake‐up times were significantly delayed relative to pre‐outbreak estimates (p < .001,  = 0.04). Occurrences of clinically meaningful sleep difficulties significantly increased from 36.0% before the outbreak to 50.5% during the outbreak (all p < .001, g ≥ 0.27). Three subgroups with distinct profiles of changes in sleep behaviours were identified: “Reduced Time in Bed”, “Delayed Sleep” and “Extended Time in Bed”. The “Reduced Time in Bed” and “Delayed Sleep” subgroups had more adverse sleep outcomes and psychological changes during the outbreak. The emergence of new sleep difficulties was independently associated with female sex, chronic illnesses, being employed, family responsibilities, earlier wake‐up times, higher stress levels, as well as heavier alcohol use and television exposure. The heterogeneity of sleep changes in response to the pandemic highlights the need for tailored interventions to address sleep problems.  相似文献   
15.
Though cerebrovascular complications of pregnancy remain relatively rare, they represent a potentially devastating event that necessitates prompt identification and treatment. Eighteen percent of strokes occurring in young women are linked to pregnancy. They occur mostly in the third trimester or during the post-partum period. Their biggest risk factors are hypertension, preeclampsia/eclampsia and migraine. Cerebrovascular events occurring during this period may involve specific pathophysiological processes that include embolic phenomena or endothelial dysfunction, but can also have common etiologies that are simply favored by the context of pregnancy. Thus, posterior encephalopathy and vasoconstriction cerebral syndrome are relatively frequently involved in cerebrovascular complications of pregnancy. Other very specific causes like amniotic fluid embolism or postpartum cardiomyopathy can also be responsible for such events. The management of stroke during pregnancy must be multidisciplinary and include a neurovascular expertise. Some conditions can lead to a long-life follow-up and modify the management of a future pregnancy.  相似文献   
16.
17.
Background The impact of various breast-cancer treatments on patients with a BRCA2 mutation has not been studied. We sought to estimate the impact of bilateral oophorectomy and other treatments on breast cancer-specific survival among patients with a germline BRCA2 mutation.Methods We identified 664 women with stage I–III breast cancer and a BRCA2 mutation by combining five different datasets (retrospective and prospective). Subjects were followed for 7.2 years from diagnosis to death from breast cancer. Tumour characteristics and cancer treatments were patient-reported and derived from medical records. Predictors of survival were determined using Cox proportional hazard models, adjusted for other treatments and for prognostic features.Results The 10-year breast-cancer survival for ER-positive patients was 78.9% and for ER-negative patients was 82.3% (adjusted HR = 1.23 (95% CI, 0.62–2.45, p = 0.55)). The 10-year breast-cancer survival for women who had a bilateral oophorectomy was 89.1% and for women who did not have an oophorectomy was 59.0% (adjusted HR = 0.45; 95% CI, 0.28–0.72, p = 0.001). The adjusted hazard ratio for chemotherapy was 0.83 (95% CI, 0.65–1.53: p = 0.56).Conclusions For women with breast cancer and a germline BRCA2 mutation, positive ER status does not predict superior survival. Oophorectomy is associated with a reduced risk of death from breast cancer and should be considered in the treatment plan.Subject terms: Targeted therapies, Breast cancer  相似文献   
18.
19.
AimsSelf-expanding metal stents provide rapid improvement of dysphagia in oesophageal cancer but are associated with complications. The aim of the present study was to test the effectiveness of an alternative treatment of combining biodegradable stents with radiotherapy.Materials and methodsA Simon two-stage single-arm prospective phase II trial design was used to determine the efficacy of biodegradable stents plus radiotherapy in patients with dysphagia caused by oesophagus cancer who were unsuitable for radical treatment. Fourteen patients were recruited and data from 12 were included in the final analyses.ResultsFive of 12 patients met the primary end point: one stent-related patient death; four further interventions for dysphagia within 16 weeks of stenting (41.7%, 95% confidence interval 15.2–72.3%). The median time to a 10-point deterioration of quality of life was 2.7 weeks. Nine patients died within 52 weeks of registration. The median time to death from any cause was 15.0 weeks (95% confidence interval 9.6–not reached).ConclusionThe high re-intervention observed, which met the pre-defined early stopping criteria, meant that the suggested alternative treatment was not sufficiently effective to be considered for a larger scale trial design. Further work is needed to define the place of biodegradable stents in the management of malignant oesophageal strictures.  相似文献   
20.
ABSTRACT

Expeditious linkage and consistent engagement in medical care is important for people with HIV’s (PWH) health. One theory on fostering linkage and engagement involves HIV status disclosure to mobilize social support. To assess disclosure and social support’s association with linkage and engagement, we conducted a qualitative study sampling black and Latino men who have sex with men (MSM of color) in the U.S. Participants' narratives presented mixed results. For instance, several participants who reported delaying, inconsistent access, or detachment from care also reported disclosing for support purposes, yet sporadic engagement suggests that their disclosure or any subsequent social support have not assisted. The findings contribute to the literature that questions disclosure and social support’s influence on care engagement, especially when decontextualized from circumstances and intentions. Our findings suggest the mechanics of disclosure and social support require planned implementation if intending to affect outcomes, especially among MSM of color. From the findings, we explore steps that may bolster interventions seeking to anchor medical care engagement.  相似文献   
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