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31.

Purpose

A number of studies have found an ethnic density effect in psychotic disorders, where the incidence for ethnic minorities increases as the neighbourhood proportional ethnic composition decreases [Morgan and Hutchinson, Psychol Med 40:705–709, (2010); Singh, Psychol Med 39:1402–1403, (2009); Schofield et al., Psychol Med 41:1263–1269, (2010)]. However, there is a mixed picture with some studies reporting no effect [Schofield et al., Psychol Med 41:1263–1269, (2010)]. This review aimed to establish the existence of the effect by answering the review question: is there an ethnic density dose effect in the prevalence of psychotic disorders?

Methods

A systematic review and meta-analysis was conducted by two independent reviewers using PsychINFO, Web of Science and PubMed databases. Studies were measured against eligibility criteria and then pooled with any discrepancies discussed between reviewers. Studies were then assessed for quality using a standardised quality assessment.

Results

In total, eight studies were included. A meta-analysis was conducted which found that the incidence of psychotic disorders was higher in low ethnic density areas than high ethnic density areas. A narrative synthesis reflected the complexity when results were broken down by individual ethnic groups where some ethnic groups had inverse or no associations with ethnic density. The synthesis also analysed methodological differences between studies.

Conclusions

The review reports evidence of an overall ethnic density dose effect for ethnic minorities, but with more mixed results for individual ethnic groups. The possible mechanisms behind this effect are explored, including exposure to racism, social capital and social cohesion hypotheses. The wide-ranging implications of the review are discussed along with recommendations for future research to continue to inform public health policy.  相似文献   
32.
Two major studies of structural changes associated with aging in human kidneys are reviewed and new information presented. The studies are the Monash University stereologically analyzed series of 319 autopsy kidneys from the United States in which 44% were white and the Mayo Clinic CT angiogram/biopsy analysis of 1,388 US kidney donors in which 97% were white. Hypertension rates in the Monash series were 48% and included moderate and severe hypertension. In the Mayo Clinic study, 12% had mild hypertension. The studies showed no relationship between glomerular number and hypertension except for a weak relationship with older white women in the Monash series. An inverse relationship was present between glomerular number and glomerular volume, a reciprocity that tended to enhance glomerular mass and by inference filtration capacity with lower nephron numbers. This relationship seemed to be present whether low nephron numbers were intrinsic or acquired. In the Mayo Clinic studies, pretransplant iothalamate clearances demonstrated that single nephron (SN) glomerular filtration rates (GFR) were similar throughout the range of glomerular number in subjects younger than 70 years, but that increased SNGFR correlated with nephron hypertrophy and increased nephrosclerosis particularly at 70 years of age and over. Hypertension at least through middle age cannot be related to a deficiency of glomeruli, but glomeruli are lost with later aging in association with adaptive nephron hypertrophy that can maintain GFR near normal. These studies help define an age-related nephropathy that overlaps with hypertension as a potential cause of end-stage renal disease when glomerulosclerosis is advanced.  相似文献   
33.
A randomized neonatal piglet trial was conducted to evaluate the safety and the effects of a plant-based formula containing almonds and buckwheat as the main ingredients on growth and plasma parameters. From postnatal day (PND) 2 to 21, the piglets were fed a dairy-based milk formula (Similac Advance) or a plant-based formula (Else Nutrition) and all piglets were euthanized at day 21. No diarrhea was observed after PND 8 and all the piglets completed the trial. Body growth, kcal intake, the complete plasma count parameters and hematological parameters were within the reference range in both groups. Organ growth and development was similar between the two groups. Plasma glucose was higher in the dairy-based-fed piglets relative to the plant-based at 2 weeks of age. Liver function biomarkers levels were greater in the plasma of the plant-based compared to the dairy-based fed group. In addition, calcium levels were higher in the plant-based fed piglets at 1 week of age. Thus, the plant-based formula tested in this study was well tolerated by the piglets and supported similar growth compared to dairy-based milk formula. Therefore, the results support the safety of the tested plant-based infant formula during the neonatal period in comparison to the dairy-based formula fed group.  相似文献   
34.
35.
More than 430 cases of rabies have been confirmed in dogs in the Nelson Mandela Bay Metropolitan Municipality of South Africa since July 2021. We describe the ongoing outbreak, its geographical spread and six related human deaths that have occurred. Further investigation of the outbreak and vaccination of the dog population is required. Raising awareness among healthcare providers, the public, and among international travellers planning to visit the region, is key for action to protect human and animal health.  相似文献   
36.
Objective : To examine the trends of all‐cause natural mortality for people aged 15 years and over in a remote Australian Aboriginal community between 1996 and 2010. Methods : The annual population in the community by gender and age group was obtained from the Australian Bureau of Statistics (ABS). All known deaths and all records of start of renal replacement therapy (RRT) for renal failure were recorded between 1996 and 2010. Five‐year aggregated death rates were calculated and the changes in natural mortality over the interval were evaluated. Mortality was compared with those of the Northern Territory (NT) Indigenous and non‐Indigenous people as a whole from 1998 to 2006. Results : Rates of natural deaths were lower in the third interval 2006–2010 relative to the first interval 1996–2000, with higher, but more rapidly falling rates for females than males. Reductions were prominent for both sexes in the 65 and over age groups, but death rates in females of earlier middle age also trended lower. The trends applied whether or not the starting of RRT was considered as a natural death. There was a similar trend in rates of natural death in the aggregate Indigenous population of NT. Conclusions: The downward trends probably reflect improvements in risk factor status since the 1960s, all‐of‐life health interventions, as well as better chronic disease management in the last two decades. The higher death rates in females than males in this community remain unexplained, but the rapid rate of decline of female death rates predicts that this gap will soon be minimised.  相似文献   
37.
We know a great deal about the cellular response to starvation via AMPK, but less is known about the reaction to nutrient excess. Insulin resistance may be an appropriate response to nutrient excess, but the cellular sensors that link these parameters remain poorly defined. In the present study we provide evidence that mitochondrial superoxide production is a common feature of many different models of insulin resistance in adipocytes, myotubes, and mice. In particular, insulin resistance was rapidly reversible upon exposure to agents that act as mitochondrial uncouplers, ETC inhibitors, or mitochondrial superoxide dismutase (MnSOD) mimetics. Similar effects were observed with overexpression of mitochondrial MnSOD. Furthermore, acute induction of mitochondrial superoxide production using the complex III antagonist antimycin A caused rapid attenuation of insulin action independently of changes in the canonical PI3K/Akt pathway. These results were validated in vivo in that MnSOD transgenic mice were partially protected against HFD induced insulin resistance and MnSOD+/− mice were glucose intolerant on a standard chow diet. These data place mitochondrial superoxide at the nexus between intracellular metabolism and the control of insulin action potentially defining this as a metabolic sensor of energy excess.  相似文献   
38.

Aims/hypothesis  

Hepatic steatosis is characterised by excessive triacylglycerol accumulation and is strongly associated with insulin resistance. An inability to efficiently mobilise liver triacylglycerol may be a key event mediating hepatic steatosis. Adipose triacylglycerol lipase (ATGL) is a key triacylglycerol lipase in the liver and we hypothesised that liver-specific overproduction of ATGL would reduce steatosis and enhance insulin action in obese rodents.  相似文献   
39.
Background/Objective: Our aim was to evaluate analgesia, motor block and pharmacokinetics of ropivacaine 0.2% and 0.75% in a femoral nerve block (FNB) in day case patients for anterior crucial ligament (ACL)‐reconstruction compared with bupivacaine 0.25% and placebo. Methods: Following ethics committee approval and informed consent, 280 patients were randomly allocated to four groups for single‐shot FNB [30 ml ropivacaine 0.2% (group RO2.0), 0.75% (RO7.5), bupivacaine 0.25% (BU2.5) and NaCl 0.9% (NaCl)]. Analgesia (pain scores, primary outcome) and motor block were assessed at 4 h (dismissal) and up to 24 h. Plasma concentration was determined up to 240 min thereafter. Results: Pain scores at 4 h were significantly higher for NaCl 4 (0–8) (median, range) (vs.) BU2.5 2 (0–8), RO2.0 3 (0–9) and RO7.5 2 (0–8) (NS within the LA groups). Patients of the NaCl group needed analgesics significantly more often (93%) within 4 h after surgery vs. 16% of group RO2.0, 19% of group RO7.5 and 19% of group BU2.5. Motor block was significantly increased with all local anesthetics without a significant difference within the LA groups 3 (0–5) in RO2.0, 3 (0–5) in RO7.5 and 3 (0–4) in BU2.5 vs. 0 (0–3) in group NaCl (median (range); scale from 0=full strength to 5=complete paralysis). Peak plasma concentrations differed significantly: RO7.5: 1.4 ± 0.4 (0.73–2.6) [μg/ml, mean ± SD (range)] after 33 ± 14 (10–40) min, RO2.0: 0.6 ± 0.3 (0.13–1.0) after 22+17 (10–60) and BU2.5: 0.3 ± 0.16 (0.05–0.62) at 31 ± 17 (10–60), respectively. Conclusion: FNB for ACL reconstruction with ropivacaine or bupivacaine provided better post‐operative analgesia than placebo without reaching toxic plasma concentrations. Significant motor block was observed after 4 h in all groups including the lowest concentration of ropivacaine but occurred even with placebo.  相似文献   
40.
背景与目的: 环氧合酶2(cyelooxygenase-2,COX-2)是花生四烯酸转化为前列腺素(prostaglandins,PGs)代谢中重要的限速酶,幽门螺杆菌(Helicobacterpylori,Hp)感染诱导胃黏膜COX-2的过度表达是胃癌发生的重要环节,但Hp感染胃黏膜细胞COX-2表达的机制尚不清楚.本研究旨在揭示Hp对人胃癌MKN45细胞COX-2表达和p38MAPK信号通路的影响,探讨COX-2表达的可能机制.方法: 采用实时荧光定量PCR(real time-PCR)检测Hp标准株NCTC11637感染对人胃痛MKN45细胞COX-2 mRNA转录的影响,Western blot检测坳COX-2蛋白表达的影响和p38MAPK信号通路的激活及其下游因子ATF-2的表达.结果: Hp感染人胃癌MKN45细胞后,COX-2 mRNA的表达明显上调,Hp感染3、6、9、12 h后COX-2 mRNA的表达量分别为正常值的3倍、7.2倍、5.1倍和4.3倍,各时间组COX-2 mRNA表达均明显高于对照组(P<0.01);Up与MKN45细胞共培养24 h后,COX-2蛋白的表达亦显著增加(P<0.01).Hp感染MKN45 20 min后,p38MAPK信号通路被激活,60 min达峰值;p38MAPK下游因子ATF-2的表达也明显增加,2 h达高峰,随着作用时间的延长,表达逐渐下降,24 h仍有表达.结论: Hp感染能诱导人胃癌MKN45细胞COX-2的表达;激活p38MAPK信号通路,增加其下游因子ATF-2的表达,可能是其诱导COX-2表达的机制.  相似文献   
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