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1.
BackgroundThe prevalence of chronic conditions such as obesity, hypertension, and diabetes is increasing in African countries. Many chronic diseases have been linked to risk factors such as poor diet and physical inactivity. Data for these behavioral risk factors are usually obtained from surveys, which can be delayed by years. Behavioral data from digital sources, including social media and search engines, could be used for timely monitoring of behavioral risk factors.ObjectiveThe objective of our study was to propose the use of digital data from internet sources for monitoring changes in behavioral risk factors in Africa.MethodsWe obtained the adjusted volume of search queries submitted to Google for 108 terms related to diet, exercise, and disease from 2010 to 2016. We also obtained the obesity and overweight prevalence for 52 African countries from the World Health Organization (WHO) for the same period. Machine learning algorithms (ie, random forest, support vector machine, Bayes generalized linear model, gradient boosting, and an ensemble of the individual methods) were used to identify search terms and patterns that correlate with changes in obesity and overweight prevalence across Africa. Out-of-sample predictions were used to assess and validate the model performance.ResultsThe study included 52 African countries. In 2016, the WHO reported an overweight prevalence ranging from 20.9% (95% credible interval [CI] 17.1%-25.0%) to 66.8% (95% CI 62.4%-71.0%) and an obesity prevalence ranging from 4.5% (95% CI 2.9%-6.5%) to 32.5% (95% CI 27.2%-38.1%) in Africa. The highest obesity and overweight prevalence were noted in the northern and southern regions. Google searches for diet-, exercise-, and obesity-related terms explained 97.3% (root-mean-square error [RMSE] 1.15) of the variation in obesity prevalence across all 52 countries. Similarly, the search data explained 96.6% (RMSE 2.26) of the variation in the overweight prevalence. The search terms yoga, exercise, and gym were most correlated with changes in obesity and overweight prevalence in countries with the highest prevalence.ConclusionsInformation-seeking patterns for diet- and exercise-related terms could indicate changes in attitudes toward and engagement in risk factors or healthy behaviors. These trends could capture population changes in risk factor prevalence, inform digital and physical interventions, and supplement official data from surveys.  相似文献   
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Angioleiomyomas are benign solitary smooth muscle tumors originating in the tunica media of vessels. They are rarely encountered within the oral cavity, and the number of reported cases specifically involving the hard palate remains small. A 39-year-old man presented with a 2-cm painless swelling on the left anterior hard palate. The mass had been present for ~5 years before presentation, during which time it had slowly enlarged. Magnetic resonance imaging (MRI) showed a uniform signal pattern with T1 signal intensity slightly higher than surrounding soft tissues and marked hyperintensity on T2-weighted sequences. Although the MRI characteristics of angioleiomyomas affecting the extremities have previously been reported, this is the first reported case describing the MRI features of an oral-cavity angioleiomyoma. In view of the inability to differentiate angioleiomyoma from other pathologies with similar MRI features, simple local excision for definitive histopathologic diagnosis remains recommended.  相似文献   
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A major risk factor for the spread of livestock diseases and their vectors is the uncontrolled transboundary movement of live animals for trade and grazing. Such movements constrain effective control of tick‐transmitted pathogens, including Theileria parva. Only limited studies have been undertaken to identify ticks and tick‐borne diseases (TTBDs) affecting cattle in central African countries, including Cameroon. We hereby report the collection of baseline data on the prevalence of T. parva in Cameroon through a countrywide cross‐sectional survey, conducted in 2016, involving collection of blood samples from cattle from 63 sites across the five agro‐ecological zones (AEZs) of the country. ELISA‐based surveillance of infected cattle was performed on 479 randomly selected samples and revealed specific antibodies to T. parva in 22.7% and T. mutans in 41.1% of cattle. Screening of 1,340 representative DNA samples for the presence of T. parva identified 25 (1.86%) positives using a p104 antigen gene‐based nested PCR assay. The positives were distributed across agro‐ecological zones I, II, III and V. None of the p104 positive cattle exhibited clinical symptoms of East Coast fever (ECF). Using reverse line blot (RLB), 58 (4.3%) and 1,139 (85%) of the samples reacted with the T. parva and T. mutans oligonucleotide probes, respectively. This represents the first report of T. parva from Cameroon. Surprisingly, no Rhipicephalus appendiculatus ticks, the main vector of T. parva, were identified in a parallel study involving comprehensive morphological and molecular survey of tick species present in the country. Only two of the 25 p104 positive cattle were PCR‐positive for the CD8+ T‐cell target schizont‐expressed antigen gene Tp1. Cloning and sequencing of Tp1 amplicons revealed sequence identity with the reference T. parva Muguga. This new finding raises serious concerns of a potential spread of ECF into the central African region.  相似文献   
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Toxoplasmosis is a healthcare problem in pregnant women and immunocompromised patients. Like humans, rats usually develop a subclinical chronic infection. LEW rats exhibit total resistance to Toxoplasma gondii infection, which is expressed in a dominant mode. A genome-wide search carried out in a cohort of F(2) progeny of susceptible BN and resistant LEW rats led to identify on chromosome 10 a major locus of control, which we called Toxo1. Using reciprocal BN and LEW lines congenic for chromosome 10 genomic regions from the other strain, Toxo1 was found to govern the issue of T. gondii infection whatever the remaining genome. Analyzes of rats characterized by genomic recombination within Toxo1, reduced the interval down to a 1.7-cM region syntenic to human 17p13. In vitro studies showed that the Toxo1-mediated refractoriness to T. gondii infection is associated with the ability of the macrophage to impede the proliferation of the parasite within the parasitophorous vacuole. In contrast, proliferation was observed in fibroblasts whatever the genomic origin of Toxo1. Furthermore, ex vivo studies indicate that macrophage controls parasitic infection spreading by a Toxo1-mediated mechanism. This forward genetics approach should ultimately unravel a major pathway of innate resistance to toxoplasmosis and possibly to other apicomplexan parasitic diseases.  相似文献   
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Euphorbia hirta is locally used in Africa and Australia to treat numerous diseases, including hypertension and edema. The diuretic effect of the E. hirta leaf extracts were assessed in rats using acetazolamide and furosemide as standard diuretic drugs. The water and ethanol extracts (50 and 100 mg/kg) of the plant produced time-dependent increase in urine output. Electrolyte excretion was also significantly affected by the plant extracts. The water extract increased the urine excretion of Na+, K+ and HCO3-. In contrast, the ethanol extract increased the excretion of HCO3- decreased the loss of K+ and had little effect on renal removal of Na+. Acetazolamide, like the water extract, increased urine output and enhanced the excretion of Na+, K+ and HCO3-. The high-ceiling diuretic, furosemide, increased the renal excretion of Na+ and Cl-; but had no effect on K+ and HCO3- loss. This study suggests that the active component(s) in the water extract of E. hirta leaf had similar diuretic spectrum to that of acetazolamide. These results validate the traditional use of E. hirta as a diuretic agent by the Swahilis and Sukumas.  相似文献   
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Introduction

Mother-to-child transmission of HIV can be reduced to<5% with appropriate antiretroviral medications. Such reductions depend on multiple health system encounters during antenatal care (ANC), delivery and breastfeeding; in countries with limited access to care, transmission remains high. In Lesotho, where 28% of women attending ANC are HIV positive but where geographic and other factors limit access to ANC and facility deliveries, a Minimum PMTCT Package was launched in 2007 as an alternative to the existing facility-based approach. Distributed at the first ANC visit, it packaged together all necessary pregnancy, delivery and early postnatal antiretroviral medications for mother and infant.

Methods

To examine the availability, feasibility, acceptability and possible negative consequences of the Minimum PMTCT Package, data from a 2009 qualitative and quantitative study and a 2010 facility assessment were used. To examine the effects on ANC and facility-based delivery rates, a difference-in-differences analytic approach was applied to 2009 Demographic and Health Survey data for HIV-tested women who gave birth before and after Minimum PMTCT Package implementation.

Results

The Minimum PMTCT Package was feasible and acceptable to providers and clients. Problems with test kit and medicine stock-outs occurred, and 46% of women did not receive the Minimum PMTCT Package until at least their second ANC visit. Providing adequate instruction on the use of multiple medications represented a challenge. The proportion of HIV-positive women delivering in facilities declined after Minimum PMTCT Package implementation, although it increased among HIV-negative women (difference-in-differences=14.5%, p=0.05). The mean number of ANC visits declined more among HIV-positive women than among HIV-negative women after implementation, though the difference was not statistically significant (p=0.09). Changes in the percentage of women receiving≥4 ANC visits did not differ between the two groups.

Conclusions

If supply issues can be resolved and adequate client educational materials provided, take-away co-packages have the potential to increase access to PMTCT commodities in countries where women have limited access to health services. However, efforts must be made to carefully monitor potential changes in ANC visits and facility deliveries, and further evaluation of adherence, safety and effectiveness are needed.  相似文献   
10.
The application of autologous fat grafting in reconstructive surgery is commonly used to improve functional form. This review aims to provide an overview of the scientific evidence on the biology of adipose tissue, the role of adipose-derived stem cells, and the indications of adipose tissue grafting in peripheral nerve surgery. Adipose tissue is easily accessible through the lower abdomen and inner thighs. Non-vascularized adipose tissue grafting does not support oxidative and ischemic stress, resulting in variable survival of adipocytes within the first 24 hours. Enrichment of adipose tissue with a stromal vascular fraction is purported to increase the number of adipose-derived stem cells and is postulated to augment the long-term stability of adipose tissue grafts. Basic science nerve research suggests an increase in nerve regeneration and nerve revascularization, and a decrease in nerve fibrosis after the addition of adipose-derived stem cells or adipose tissue. In clinical studies, the use of autologous lipofilling is mostly applied to secondary carpal tunnel release revisions with promising results. Since the use of adipose-derived stem cells in peripheral nerve reconstruction is relatively new, more studies are needed to explore safety and long-term effects on peripheral nerve regeneration. The Food and Drug Administration stipulates that adipose-derived stem cell transplantation should be minimally manipulated, enzyme-free, and used in the same surgical procedure, e.g. adipose tissue grafts that contain native adipose-derived stem cells or stromal vascular fraction. Future research may be shifted towards the use of tissue-engineered adipose tissue to create a supportive microenvironment for autologous graft survival. Shelf-ready alternatives could be enhanced with adipose-derived stem cells or growth factors and eliminate the need for adipose tissue harvest.Key Words: adipose tissue, adipose-derived stem cells, angiogenesis, autologous fat grafting, nerve injury, nerve regeneration, paracrine environment, peripheral nerve reconstruction, stem cell secretome, tissue engineering  相似文献   
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