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Reduced phospholipase A2 (PLA2) activity has been reported in the brain and in blood cells of patients with Alzheimer’s disease (AD). Individuals with mild cognitive impairment (MCI) are at increased risk of developing AD. In the present study, we determined the activity of distinct PLA2 subgroups (iPLA2, sPLA2 and cPLA2) in older adults with MCI as compared to patients with mild dementia due to AD and to cognitively healthy controls. We investigated whether decreased PLA2 activity at baseline is associated with the progression of MCI to AD upon follow-up during a period of 4 years. The activity of PLA2 subgroups was determined in platelets from 169 elderly adults. Progression of MCI to AD was ascertained by standard clinical criteria for AD upon follow-up. At baseline, iPLA2 activity was significantly decreased (p = 0.001) in patients with AD and MCI as compared to controls. Patients with MCI who progressed to AD during follow-up showed significantly lower iPLA2 activity at baseline as compared to patients with MCI who did not progress to AD (p = 0.009). Moreover, subjects from the control group at baseline who progressed to MCI during follow-up had lower sPLA2 and cPLA2 (p = 0.014 and p = 0.009, respectively). Our findings suggest that low platelet iPLA2 activity may be a risk marker for AD in subjects with MCI. Moreover, low sPLA2 and cPLA2 were related to cognitive decline in healthy controls, suggesting a relationship with the very early stages of the disease.  相似文献   
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Adolescent pregnancy remains a public health concern in both developed and developing countries. Portugal and Brazil represent some of the best examples of this phenomenon. The present study aimed to identify sociodemographic, sexual, and reproductive health-related variables associated with adolescent pregnancy among students from low socioeconomic backgrounds in both countries. The sample included 984 female adolescents, among whom 215 became pregnant. Living with a partner and lack of information about sex and contraception from the family were the best explicative factors for pregnancy occurrence in both countries. Country-specific variables were also identified. Our results may contribute to developing global preventive interventions, addressing the school as an ideal setting for primary intervention and considering culture-specific characteristics of high-risk populations.  相似文献   
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IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery.  相似文献   
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Excessive sugar intake represents an increased risk of developing non-communicable diseases (e.g., obesity, cardiometabolic diseases, and dental diseases). Still, it is unclear whether people are aware of these adverse health outcomes. The current study systematically examined the extent to which people associate health conditions with excessive sugar intake. Participants (N = 1010 Portuguese volunteers) freely reported all health conditions they associated with excessive sugar consumption and rated the strength of these associations for eight specific health conditions. All participants reported health conditions associated with excessive sugar intake, with the most frequent being risk factors for cardiometabolic diseases (e.g., diabetes), cardiovascular diseases, oral problems, oncological and mental health conditions. Moreover, participants considered diabetes, overweight/obesity, and oral problems as being the conditions most related to excessive sugar intake. Women, participants with children in the household, and experts in health/nutrition rated excessive sugar intake as being more strongly linked to some of the health conditions. The identification of the health conditions that people associate with excessive sugar consumption may inform policymakers, educators, and health professionals and support interventions targeting the general public or specific groups (e.g., overweight people) in raising awareness of potential adverse health outcomes and, ultimately, contribute to reducing sugar intake.  相似文献   
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Melanin-concentrating hormone (MCH) is a ubiquitous vertebrate neuropeptide predominantly synthesized by neurons of the diencephalon that can act through two G protein-coupled receptors, called MCHR1 and MCHR2. The expression of Mchr1 has been investigated in both rats and mice, but its synthesis remains poorly described. After identifying an antibody that detects MCHR1 with high specificity, we employed immunohistochemistry to map the distribution of MCHR1 in the CNS of rats and mice. Multiple neurochemical markers were also employed to characterize some of the neuronal populations that synthesize MCHR1. Our results show that MCHR1 is abundantly found in a subcellular structure called the primary cilium, which has been associated, among other functions, with the detection of free neurochemical messengers present in the extracellular space. Ciliary MCHR1 was found in a wide range of areas, including the olfactory bulb, cortical mantle, striatum, hippocampal formation, amygdala, midline thalamic nuclei, periventricular hypothalamic nuclei, midbrain areas, and in the spinal cord. No differences were observed between male and female mice, and interspecies differences were found in the caudate-putamen nucleus and the subgranular zone. Ciliary MCHR1 was found in close association with several neurochemical markers, including tyrosine hydroxylase, calretinin, kisspeptin, estrogen receptor, oxytocin, vasopressin, and corticotropin-releasing factor. Given the role of neuronal primary cilia in sensing free neurochemical messengers in the extracellular fluid, the widespread distribution of ciliary MCHR1, and the diverse neurochemical populations who synthesize MCHR1, our data indicate that nonsynaptic communication plays a prominent role in the normal function of the MCH system.  相似文献   
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