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971.
972.
Male circumcision (MC) reduces high‐risk human papillomavirus (HR‐HPV) infection in female partners. We evaluated the intensity of HR‐HPV viral DNA load in HIV‐negative, HR‐HPV‐positive female partners of circumcised and uncircumcised men. HIV‐negative men and their female partners were enrolled in randomized trials of MC in Rakai, Uganda. Vaginal swabs were tested for HR‐HPV genotypes by Roche HPV Linear Array which provides a semi‐quantitative measure of HPV DNA by the intensity of genotype‐specific bands (graded:1–4). We assessed the effects of MC on female HR‐HPV DNA load by comparing high intensity linear array bands (3–4) to low intensity bands (1–2) using an intention‐to‐treat analysis. Prevalence risk ratios (PRR) of high intensity bands in partners of intervention versus control arm men were estimated using log‐binomial regression with robust variance. The trial included 335 women with male partners in the intervention arm and 340 in the control arm. At enrollment, the frequency of HR‐HPV high intensity linear array bands was similar in both study arms. At 24 months follow‐up, the prevalence of high intensity bands among women with detectable HR‐HPV was significantly lower in partners of intervention arm (42.7%) than control arm men (55.1%, PRR = 0.78, 95%CI 0.65–0.94, p = 0.02), primarily among incident HR‐HPV infections (PRR = 0.66, 95% CI 0.50–0.87, p = 0.003), but not persistent infections (PRR = 1.02, 95% CI 0.83–1.24). Genotypes with high HR‐HPV band intensity were more likely to persist (adjHR = 1.27 95% CI 1.07–1.50), irrespective of male partner circumcision status. MC reduces HR‐HPV DNA load in newly infected female partners.  相似文献   
973.
Diabetes mellitus (DM) is a growing epidemic with global proportions. It is estimated that in 2019, 463 million adults aged 20-79 years were living with DM. The latest evidence shows that DM continues to be a significant global health challenge and is likely to continue to grow substantially in the next decades, which would have major implications for healthcare expenditures, particularly in developing countries. Hence, new conceptual and methodological approaches to tackle the epidemic are long overdue. Spatial epidemiology has been a successful approach to control infectious disease epidemics like malaria and human immunodeficiency virus. The implementation of this approach has been expanded to include the study of non-communicable diseases like cancer and cardiovascular diseases. In this review, we discussed the implementation and use of spatial epidemiology and Geographic Information Systems to the study of DM. We reviewed several spatial methods used to understand the spatial structure of the disease and identify the potential geographical drivers of the spatial distribution of DM. Finally, we discussed the use of spatial epidemiology on the design and implementation of geographically targeted prevention and treatment interventions against DM.  相似文献   
974.
Background: Unlike medical lasers, intense pulsed light (IPL) devices are largely unregulated and unclassified as to degree of safety hazard. With the exception of most of the USA, the United Kingdom and parts of Europe, the Far East and Australia, the sale of IPLs is generally unrestricted, with the majority being sold into the beauty therapy and spa markets. Standards are only imposed on manufacturers for technical performance data and operating tolerances determined by CE‐compliance under electrical safety standards or the EU Medical Device Directive. Currently, there is no requirement for measurement of key IPL performance characteristics. Objective: To identify the key IPL parameters, emphasize their importance in terms of safe and effective treatment and provide examples of preliminary measurement methods. These measurements can highlight changes in an IPL device's performance, improving patient safety and treatment efficacy. Methods: Five key parameters were identified as having an important role to play in the way light interacts with the skin, and therefore an important role in patient safety and effective treatment. Simple methods were devised to measure the parameters, which include fluence, pulse duration, pulse profile, spectral output and time‐resolved spectral output. Results: The measurement methods permitted consistent and comparable measurements to be made by two of the authors at working clinic locations on 18 popular IPL devices and allowed assessment of output variations. Results showed discrepancies between the measured IPL device outputs and those values displayed on the system or claimed by the manufacturers. The importance of these discrepancies and their impact is discussed. Conclusions: This study, of 18 popular devices in regular daily use in England and Wales, provides example methods for measuring key IPL device parameters and highlights the need for regular measurement of at least those five key parameters measured in this study. These methods can help service technicians to check performance and eliminate device malfunction.  相似文献   
975.
WY Tong  W Shen  CW Yeung  Y Zhao  SH Cheng  PK Chu  D Chan  GC Chan  KM Cheung  KW Yeung  YW Lam 《Biomaterials》2012,33(31):7686-7698
Although many studies have demonstrated that cell phenotype is affected by the surface properties of biomaterials, these materials often fail to mimic the complexity of the native tissue microenvironment (TME). In this study, we have developed a new experimental model that allows the characterisation and functional reconstruction of natural TME. We discovered that mesenchymal stem cells (MSC) cultured on cryostat sections of bovine Achilles tendon adopted an elongated and aligned morphology, and expressed tenocyte marker tenomodulin (TNMD). This suggests that tendon sections contain the signalling cues that guide MSCs to commit to the tenogenic lineage. To reconstruct this instructive niche, we prepared PDMS replica by using tendon sections as template. The resulting bioimprint faithfully copied the physical topography and elasticity of the section. This replica, when coated with collagen 1, supported tenogenesis of MSC without requiring exogenous growth factors. This study illustrates how extracellular biophysical and biochemical features intertwines to form a niche that influences the cell fate and demonstrated that such complex information could be conveniently reconstructed with synthetic materials and purified extracellular matrix proteins.  相似文献   
976.
BNP (B-type natriuretic peptide) has been reported to be elevated in preclinical states of vascular damage. To elucidate the relationship between plasma BNP and endothelial function, we have investigated the relationship between BNP and endothelial function in a cohort of subjects comprising healthy subjects as well as at-risk subjects with cardiovascular risk factors. To also clarify the relative contribution of different biological pathways to the individual variation in endothelial function, we have examined the relationship between a panel of multiple biomarkers and endothelial function. A total of 70 subjects were studied (mean age, 58.1±4.6?years; 27% had a history of hypertension and 18% had a history of hypercholesterolaemia). Endothelium-dependent vasodilatation was evaluated by the invasive ACH (acetylcholine)-induced forearm vasodilatation technique. A panel of biomarkers of biological pathways was measured: BNP, haemostatic factors PAI-1 (plasminogen-activator inhibitor 1) and tPA (tissue plasminogen activator), inflammatory markers, including cytokines [hs-CRP (high sensitive C-reactive protein), IL (interleukin)-6, IL-8, IL-18, TNFα (tumour necrosis factor α) and MPO (myeloperoxidase] and soluble adhesion molecules [E-selectin and sCD40 (soluble CD40)]. The median BNP level in the study population was 26.9 pg/ml. Multivariate regression analyses show that age, the total cholesterol/HDL (high-density lipoprotein) ratio, glucose and BNP were independent predictors of endothelial function, and BNP remained an independent predictor (P=0.009) in a binary logistic regression analysis using FBF (forearm blood flow) as a dichotomous variable based on the median value. None of the other plasma biomarkers was independently related to ACH-mediated vasodilatation. In a strategy using several biomarkers to relate to endothelial function, plasma BNP was found to be an independent predictor of endothelial function as assessed by endothelium-dependent vasodilatation in response to ACH.  相似文献   
977.
Fetal cardiac function has been shown to be a marker of disease severity in many conditions, including intrauterine growth restriction, congenital heart defects or disease (CHD), twin-to-twin transfusion syndrome, idiopathic hydrops, fetal arrhythmias, and others. It is often targeted for evaluation of patient management, for providing complete and accurate diagnoses in CHD, for patient counseling, or in referring for fetal cardiac interventions. In this review we will describe the use of M-mode and 4D spatiotemporal image correlation in fetal cardiac evaluation, the parameters that can be measured, and their application to clinical practice.  相似文献   
978.
979.

Background

Serbia has proclaimed access to healthcare as a human right. In a context wherein the Roma population are disadvantaged, the aim of this study was to assess whether the Roma population are able to effectively access primary care services, and if not, what barriers prevent them from doing so. The history of the Roma in Serbia is described in detail so as to provide a context for their current vulnerable position.

Methods

Disaggregated data were analyzed from three population groups in Serbia; the general population, the Roma population, and the poorest quintile of the general population not including the Roma. The effective coverage framework, which incorporates availability, affordability, accessibility, acceptability, and effectiveness of health services, was used to structure the secondary data analysis. Acute respiratory infection (ARI) in children less than five years of age was used as an example as this is the leading cause of death in children under 5 years old in Serbia.

Results

Roma children were significantly more likely to experience an ARI than either the general population or the poorest quintile of the general population, not including the Roma. All three population groups were equally likely to not receive the correct treatment regime of antibiotics. An analysis of the factors that affect quality of access to health services reveal that personal documentation is a statistically significant problem; availability of health services is not an issue that disproportionately affects the Roma; however the geographical accessibility and affordability are substantive issues that disproportionately affect the Roma population. Affordability of services affected the Roma and the poorest quintile and affordability of medications significantly affected all three population groups. With regards to acceptability, mothers from all three population groups are equally likely to recognize the importance of seeking treatment.

Conclusions

The Roma should be assisted in applying for personal documentation, the geographical accessibility of clinics needs to be addressed, and the costs of healthcare visits and medications should be reviewed. Areas for improvement specific to ARI are the costs of antibiotics and the diagnostic accuracy of providers. A range of policy recommendations are outlined.  相似文献   
980.
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