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91.
Journal of Ethology - Incidental stimuli produced by animal aggregations may be utilised by conspecifics to locate key resources in areas, where resources are patchily distributed and temporally...  相似文献   
92.
Experiencing psychological trauma during childhood and/or adolescence is associated with an increased risk of psychosis in adulthood. However, we lack a clear knowledge of how developmental trauma induces vulnerability to psychotic symptoms. Understanding the psychological processes involved in this association is crucial to the development of preventive interventions and improved treatments. We sought to systematically review the literature and combine findings using meta‐analytic techniques to establish the potential roles of psychological processes in the associations between developmental trauma and specific psychotic experiences (i.e., hallucinations, delusions and paranoia). Twenty‐two studies met our inclusion criteria. We found mediating roles of dissociation, emotional dysregulation and post‐traumatic stress disorder (PTSD) symptoms (avoidance, numbing and hyperarousal) between developmental trauma and hallucinations. There was also evidence of a mediating role of negative schemata, i.e. mental constructs of meanings, between developmental trauma and delusions as well as paranoia. Many studies to date have been of poor quality, and the field is limited by mostly cross‐sectional research. Our findings suggest that there may be distinct psy­chological pathways from developmental trauma to psychotic phenomena in adulthood. Clinicians should carefully ask people with psychosis about their history of developmental trauma, and screen patients with such a history for dissociation, emotional dysregulation and PTSD symptoms. Well conducted research with prospective designs, including neurocognitive assessment, is required in order to fully understand the biopsychosocial mechanisms underlying the association between developmental trauma and psychosis.  相似文献   
93.
The COVID-19 outbreak has highlighted our vulnerability to novel infections.Faced with this threat and no effective treatment, in line with many other countries, the UK adopted enforced social distancing (lockdown) to reduce transmission—successfully reducing the reproductive number R below one. However, given the large pool of susceptible individuals that remain, complete relaxation of controls is likely to generate a substantial further outbreak. Vaccination remains the only foreseeable means of both containing the infection and returning to normal interactions and behaviour. Here, we consider the optimal targeting of vaccination within the UK, with the aim of minimising future deaths or quality adjusted life year (QALY) losses. We show that, for a range of assumptions on the action and efficacy of the vaccine, targeting older age groups first is optimal and may be sufficient to stem the epidemic if the vaccine prevents transmission as well as disease.  相似文献   
94.
95.
Determine if sex differences exist in clinical characteristics and outcomes of adults hospitalized for coronavirus disease 2019 (COVID-19) in a US healthcare system. Case series study. Sequentially hospitalized adults admitted for COVID-19 at two tertiary care academic hospitals in New Orleans, LA, between 27 February and 15 July 2020. Measures included demographics, comorbidities, presenting symptoms, and laboratory results. Outcomes included intensive care unit admission (ICU), invasive mechanical ventilation (IMV), and in-hospital death. We included 776 patients (median age 60.5 years; 61.4% women, 75% non-Hispanic Black). Rates of ICU, IMV, and death were similar in both sexes. In women versus men, obesity (63.8 vs 41.6%, P < 0.0001), hypertension (77.6 vs 70.1%, P = 0.02), diabetes (38.2 vs 31.8%, P = 0.06), chronic obstructive pulmonary disease (COPD, 22.1 vs 15.1%, P = 0.015), and asthma (14.3 vs 6.9%, P = 0.001) were more prevalent. More women exhibited dyspnea (61.2 vs 53.7%, P = 0.04), fatigue (35.7 vs 28.5%, P = 0.03), and digestive symptoms (39.3 vs 32.8%, P = 0.06) than men. Obesity was associated with IMV at a lower BMI (> 35) in women, but the magnitude of the effect of morbid obesity (BMI ≥ 40) was similar in both sexes. COPD was associated with ICU (adjusted OR (aOR), 2.6; 95%CI, 1.5–4.3) and IMV (aOR, 1.8; 95%CI, 1.2–3.1) in women only. Diabetes (aOR, 2.6; 95%CI, 1.2–2.9), chronic kidney disease (aOR, 2.2; 95%CI, 1.3–5.2), elevated neutrophil-to-lymphocyte ratio (aOR, 2.5; 95%CI, 1.4–4.3), and elevated ferritin (aOR, 3.6; 95%CI, 1.7–7.3) were independent predictors of death in women only. In contrast, elevated D-dimer was an independent predictor of ICU (aOR, 7.3; 95%CI, 2.7–19.5), IMV (aOR, 6.5; 95%CI, 2.1–20.4), and death (aOR, 4.5; 95%CI, 1.2–16.4) in men only. This study highlights sex disparities in clinical determinants of severe outcomes in COVID-19 patients that may inform management and prevention strategies to ensure gender equity.  相似文献   
96.
The impact of Quaternary glaciation on the development of phylogeographic structure in plant species is well documented. In unglaciated landscapes, phylogeographic patterns tend to reflect processes relating to persistence and stochasticity, yet other factors, associated with the palaeogeographical history of the landscape, including geomorphological events, can also have a significant influence. The unglaciated landscape of south‐western Western Australia is an ideal location to observe these ancient drivers of lineage diversification, with tectonic activity associated with the Darling Fault in the late Pliocene attributed to patterns of deep phylogeographic divergence in a widespread tree from this region. Interestingly, other species within this region have not shown this pattern and this palaeogeographical boundary therefore presents an opportunity to examine age and historical distribution of plant species endemic to this region. In this study, we assess patterns of genetic diversity and structure across 28 populations of the widespread shrub Banksia sessilis using three cpDNA markers and nine nuclear microsatellite markers. Sixteen cpDNA haplotypes were identified, comprising two major chloroplast DNA lineages that are estimated to have diverged in the Pliocene, approximately 3.3 million years ago. This timing coincides with major geomorphological processes in the landscape, including the separation of the Darling Plateau from the adjacent Swan Coastal Plain, as well as eustatic changes on the Swan Coastal Plain that are likely to have resulted in the physical isolation of historical plant lineages. Chloroplast lineages were broadly aligned with populations associated with older lateritic soils of the Darling Plateau and Geraldton sandplains or the younger sandy soils associated with the Swan Coastal Plain and Southern Coastline. This structural pattern of lateritic versus non‐lateritic division was not observed in the nuclear microsatellite data that identified three genetic clades that roughly corresponded to populations in the North, South, and Central portions of the distributions.  相似文献   
97.
98.
Certain conditions, such as several weeks of high-fat diet, disrupt endoplasmic reticulum (ER) homeostasis and activate an adaptive pathway referred as the unfolded protein response. When the unfolded protein response fails, the result is the development of inflammation and insulin resistance. These two pathological states are known to be improved by regular exercise training but the mechanisms remain largely undetermined. As it has recently been shown that the unfolded protein response is regulated by exercise, we hypothesised that concomitant treadmill exercise training (HFD+ex) prevents ER homeostasis disruption and its downstream consequences induced by a 6-week high-fat diet (HFD) in mice by activating the protective unfolded protein response. Several well-documented markers of the unfolded protein response were measured in the soleus and tibialis anterior muscles as well as in the liver and pancreas. In HFD mice, an increase in these markers was observed (from 2- to 15-fold, P?<?0.05) in all tissues studied. The combination of HFD+ex increased the expression of several markers further, up to 100 % compared to HFD alone (P?<?0.05). HFD increased inflammatory markers both in the plasma (IL-6 protein, 2.5?±?0.52-fold; MIP-1α protein, 1.3?±?0.13-fold; P?<?0.05) and in the tissues studied, and treadmill exercise attenuated the inflammatory state induced by HFD (P?<?0.05). However, treadmill exercise could not reverse HFD-induced whole body glucose intolerance, assessed by OGTT (AUC, 1.8?±?0.29-fold, P?<?0.05). In conclusion, our results show that a HFD activated the unfolded protein response in mouse tissues in vivo, and that endurance training promoted this response. We speculate that the potentiation of the unfolded protein response by endurance training may represent a positive adaptation protecting against further cellular stress.  相似文献   
99.
Background aimsWe recently showed that co-transplantation of mesenchymal stromal cells (MSCs) improves islet function and revascularization in vivo. Pre-transplant islet culture is associated with the loss of islet cells. MSCs may enhance islet cell survival or function by direct cell contact mechanisms and soluble mediators. We investigated the capacity of MSCs to improve islet cell survival or β-cell function in vitro using direct and indirect contact islet-MSC configurations. We also investigated whether pre-culturing islets with MSCs improves islet transplantation outcome.MethodsThe effect of pre-culturing islets with MSCs on islet function in vitro was investigated by measuring glucose-stimulated insulin secretion. The endothelial cell density of fresh islets and islets cultured with or without MSCs was determined by immunohistochemistry. The efficacy of transplanted islets was tested in vivo using a syngeneic streptozotocin-diabetic minimal islet mass model. Graft function was investigated by monitoring blood glucose concentrations.ResultsIndirect islet-MSC co-culture configurations did not improve islet function in vitro. Pre-culturing islets using a direct contact MSC monolayer configuration improved glucose-stimulated insulin secretion in vitro, which correlated with superior islet graft function in vivo. MSC pre-culture had no effect on islet endothelial cell number in vitro or in vivo.ConclusionsPre-culturing islets with MSCs using a direct contact configuration maintains functional β-cell mass in vitro and the capacity of cultured islets to reverse hyperglycemia in diabetic mice.  相似文献   
100.

Objectives

The current study investigates the acceptability, effectiveness and uptake of internet-delivered cognitive behavioural therapy (iCBT) amongst older individuals (>60 years) seeking psychiatric treatment in general practice.

Methods

The sample consisted of 2413 (mean age 39.5; range 18–83 years) patients prescribed iCBT through This Way Up clinic by their primary care clinician. The intervention consisted of six fully automated, unassisted online lessons specific to four disorders major depression, generalised anxiety disorder, panic disorder or social phobia. Patients were categorised into five age groups (18–29 years, 30–39 years, 40–49 years, 50–59 years, 60 years and above). 225 (9.3%) patients were aged over 60 years. Analyses were conducted across the four disorders to ensure sufficient sample sizes in the 60 years and older age group. Age differences in adherence to the six lesson courses were assessed to demonstrate acceptability. Age-based reductions in psychological distress (Kessler Psychological Distress Scale; K10) and disability (the World Health Organisation Disability Assessment Schedule; WHODAS-II) were compared to demonstrate effectiveness. To evaluate the uptake of iCBT, the age distribution of those commencing iCBT was compared with the prevalence of these disorders in the 2007 Australian National Survey of Mental Health and Well-Being.

Results

Older adults were more likely to complete all six lessons when compared with their younger counterparts. Marginal model analyses indicated that there were significant reductions in the K10 and WHODAS-II from baseline to post-intervention, regardless of age (p<0.001). The measurement occasion by age interactions were not significant, indicating that individuals showed similar reductions in the K10 and WHODAS-II regardless of age. In general, the age distribution of individuals commencing the iCBT courses matched the age distribution of the four diagnoses in the Australian general population, indicating that iCBT successfully captures older individuals who need treatment.

Conclusion

iCBT is effective and acceptable for use in older populations.  相似文献   
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