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1.
ABSTRACT

Informal settlements remain a public health problem as they lack basic infrastructure. Furthermore, it is challenging to enforce public health regulations and protocols to prevent the spread of infection during a pandemic. This paper was set out to explore the impact of lockdown during COVID-19 among people living in informal settlements. An exploratory qualitative design was utilised. Purposive sampling was used to select research participants. In-depth one-to-one interviews were held involving 30 research participants through a WhatsApp online telephone platform. A thematic approach underpinned by the four stages of data analysis in interpretive phenomenological analysis was utilised to analyse the data. The study found that during the the research participants were affected by lack of space to practice social distancing, over-burdened infrastructure, lack of savings, loss of income and shortage of food, hunger and diseases, anxiety and depression and poor access to education. There is a need to prioritise the needs of informal settlers and endeavour to establish permanent homes. Health promotion and communication initiatives and pandemic awareness programmes are needed to mitigate the impact of lockdown during a pandemic in informal settlements.  相似文献   
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We examined the impact of physical activity (PA) on surrogate markers of cardiovascular health in adolescents. 52 healthy students (28 females, mean age 14.5 ± 0.7 years) were investigated. Microvascular endothelial function was assessed by peripheral arterial tonometry to determine reactive hyperemic index (RHI). Vagal activity was measured using 24 h analysis of heart rate variability [root mean square of successive normal-to-normal intervals (rMSSD)]. Exercise testing was performed to determine peak oxygen uptake ( $ \dot{V}{\text{O}}_{{2{\text{ peak}}}} $ ) and maximum power output. PA was assessed by accelerometry. Linear regression models were performed and adjusted for age, sex, skinfolds, and pubertal status. The cohort was dichotomized into two equally sized activity groups (low vs. high) based on the daily time spent in moderate-to-vigorous PA (MVPA, 3,000–5,200 counts.min?1, model 1) and vigorous PA (VPA, >5,200 counts.min?1, model 2). MVPA was an independent predictor for rMSSD (β = 0.448, P = 0.010), and VPA was associated with maximum power output (β = 0.248, P = 0.016). In model 1, the high MVPA group exhibited a higher vagal tone (rMSSD 49.2 ± 13.6 vs. 38.1 ± 11.7 ms, P = 0.006) and a lower systolic blood pressure (107.3 ± 9.9 vs. 112.9 ± 8.1 mmHg, P = 0.046). In model 2, the high VPA group had higher maximum power output values (3.9 ± 0.5 vs. 3.4 ± 0.5 W kg?1, P = 0.012). In both models, no significant differences were observed for RHI and $ \dot{V}{\text{O}}_{{ 2 {\text{ peak}}}} $ . In conclusion, in healthy adolescents, PA was associated with beneficial intensity-dependent effects on vagal tone, systolic blood pressure, and exercise capacity, but not on microvascular endothelial function.  相似文献   
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The zebrafish has recently become a source of new data on the mechanisms of neural stem cell (NSC) maintenance and ongoing neurogenesis in adult brains. In this vertebrate, neurogenesis occurs at high levels in all ventricular regions of the brain, and brain injuries recover successfully, owing to the recruitment of radial glia, which function as NSCs. This new vertebrate model of adult neurogenesis is thus advancing our knowledge of the molecular cues in use for the activation of NSCs and fate of their progeny. Because the regenerative potential of somatic stem cells generally weakens with increasing age, it is important to assess the extent to which zebrafish NSC potential decreases or remains unaltered with age. We found that neurogenesis in the ventricular zone, in the olfactory bulb, and in a newly identified parenchymal zone of the telencephalon indeed declines as the fish ages and that oligodendrogenesis also declines. In the ventricular zone, the radial glial cell population remains largely unaltered morphologically but enters less frequently into the cell cycle and hence produces fewer neuroblasts. The neuroblasts themselves do not change their behavior with age and produce the same number of postmitotic neurons. Thus, decreased neurogenesis in the physiologically aging zebrafish brain is correlated with an increasing quiescence of radial glia. After injuries, radial glia in aged brains are reactivated, and the percentage of cell cycle entry is increased in the radial glia population. However, this reaction is far less pronounced than in younger animals, pointing to irreversible changes in aging zebrafish radial glia. J. Comp. Neurol. 521: 3099–3115, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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Course trajectory analyses have been performed primarily for treatment response in acute episodes of schizophrenic disorders. As yet, corresponding data for the long-term course are lacking. Within a multicenter prospective observational study, 268 patients with schizophrenia were assessed at discharge from hospital and followed up after 6, 12, 18, and 24 months. A latent class growth analysis was performed on the scores from the Positive and Negative Syndrome Scale (PANSS). A two-class conditional latent class model showed the best data fit (Entropy: 0.924). The model divided the sample into a group with amelioration in all PANSS subscales (60%) and a group with stable positive/negative and deteriorating general psychopathology symptoms (40%). Global functioning (GAF score), gender, age, living situation and involuntary admission predicted course trajectory class membership. The model was predictive of significant differences between the two groups in health care service costs and quality of life. The results underline the heterogeneous course of the illness, which ranged from amelioration to deterioration over a 2-year period. Statistical models such as trajectory analysis could help to identify more homogenous subtypes in schizophrenia.  相似文献   
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Kinesin motor proteins exert essential cellular functions in all eukaryotes. They control mitosis, migration and intracellular transport through interaction with microtubules. Small molecule inhibitors of the mitotic kinesin KiF11/Eg5 are a promising new class of anti-neoplastic agents currently evaluated in clinical cancer trials for solid tumors and hematological malignancies. Here we report induction of Eg5 and four other mitotic kinesins including KIF20A/Mklp2 upon stimulation of in vivo angiogenesis with vascular endothelial growth factor-A (VEGF-A). Expression analyses indicate up-regulation of several kinesin-encoding genes predominantly in lymphoblasts and endothelial cells. Chemical blockade of Eg5 inhibits endothelial cell proliferation and migration in vitro. Mitosis-independent vascular outgrowth in aortic ring cultures is strongly impaired after Eg5 or Mklp2 protein inhibition. In vivo, interfering with KIF11/Eg5 function causes developmental and vascular defects in zebrafish and chick embryos and potent inhibition of tumor angiogenesis in experimental tumor models. Besides blocking tumor cell proliferation, impairing endothelial function is a novel mechanism of action of kinesin inhibitors.  相似文献   
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This paper is meant to serve as a basis for discussion regarding the service or external role of schools of public health (SPHs). A number of countries in Eastern Europe are developing and establishing their own SPHs, at the same time trying to come to terms with the development of the public health function, its organisation, and its core activities in their respective countries. Although the position and the role of a school of public health cannot be seen outside the context in which it is functioning, including it's institutional setting, a thorough analysis of this context would be beyond the scope of this paper. The paper therefore concentrates on the roles of a school of public health, specifically the service role, and will seek to define that role. Further, the paper will look at how this role has been translated into the mission and policies of the SPH and how this role is operationalised. Finally, points for consideration and actions to be taken are suggested when defining the service role of a SPH.  相似文献   
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PURPOSE: We present the rationale and design of the Zambian Exclusive Breast-feeding Study (ZEBS), a randomized trial evaluating the efficacy of short-duration exclusive breast-feeding (EBF) as a strategy to reduce postnatal human immunodeficiency virus (HIV) transmission while preserving the other health benefits of this important mode of infant feeding. METHODS: One thousand two hundred HIV-positive pregnant women were recruited in Lusaka, Zambia, and followed with their infants for 24 months. In addition to Nevirapine (NVP), all women received intensive and frequent clinic- and home-based counseling to support exclusive breast-feeding. When the infant was 1 week of age, half of the women were randomly assigned to a group encouraged to abruptly (<24 h) cease all breast-feeding at 4 months. The primary outcome of the experimental (randomized) comparison is HIV-free survival at 24 months. The design is also observational and will compare HIV transmission rates between those who do and do not adhere to the counseling intervention promoting exclusive breast-feeding. CONCLUSION: Our study aims to quantify the benefit-risk ratio of early cessation of exclusive breast-feeding to interrupt mother-to-child transmission of HIV with an intensive behavioral intervention and has both observational and experimental analytic approaches. Our study design assesses efficacy and also has a prominent applied component that if the intervention is effective, it will permit rapid and sustainable adoption within low-resource communities.  相似文献   
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BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a worldwide public health problem with increasing morbidity and mortality. The aim of this proposal is to contribute to the improvement of COPD prevention by identifying groups at risk for COPD and targeting them for preventive interventions. METHODS: Based on the existing organizational structures for COPD detection, detailed analysis of the determinants of COPD will allow to identify groups at high risk to develop COPD. The Stepwise Target Group-Oriented Prevention (STOP) model developed during this study proposes an integrated identification and intervention strategy for high-risk groups. RESULTS: Apart from smoking, other environmental determinants and host factors contribute to further lung function's rapid decline. Combined with smoking, these factors increase the risk for COPD. Target groups for early disease detection and appropriate interventions can be identified by the presence of one or more known risk factors and by identification of high-risk groups. CONCLUSION: The Stepwise Target Group-Oriented Prevention (STOP) strategy is a step toward improvement in COPD prevention, by shifting the focus from the group of a focus symptomatic smokers aged 45+ years to much earlier and preventable stages of the disease, that is, from disease treatment to risk management.  相似文献   
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