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European Journal of Nutrition - The French Nutri-Bébé 2013 study aimed to assess the nutritional intake of infants and young children in comparison with the recommendations of the 2013...  相似文献   
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Glial cells have a major role in protecting neurons against various forms of stress. Especially, astrocytes mediate the bulk of glutamate clearance in the brain via specific membrane transporters (GLAST and GLT1), thereby preventing the occurrence of excitotoxic events. Although glutamate-mediated mechanisms are thought to contribute to nigral dopaminergic neuron degeneration in Parkinson's disease, detailed information on the organization of glia in the substantia nigra is still lacking. The present study was performed to provide quantitative information on the organization of astroglia and on the relationships between astrocytes and excitatory synapses in the rat substantia nigra. Using immunolabeling of GLT1 and confocal imaging, we found that the substantia nigra was filled with a dense meshwork of immunoreactive astrocyte processes. Stereological analysis performed on electron microscope images revealed that the density of immunoreactive astrocyte plasma membranes was substantial, close to 1 μm2/μm3, in the substantia nigra neuropil, both in the pars compacta and the pars reticulata. Excitatory synapses had on average two thirds of their perimeters free from glia, a disposition that may favor transmitter spillover. The density of glutamatergic synapses, as quantified on confocal images by the simultaneous detection of bassoon and of vesicular glutamate transporter 1 or 2, was very low (0.01 and 0.025 per μm3 in the reticulata and compacta subdivisions, respectively). Thus the ratio of GLT1-expressing glial membrane surface to glutamatergic synapses was very high (40–100 μm2), suggesting an efficient regulation of extracellular glutamate concentrations.  相似文献   
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Extensive preclinical evaluation of griffithsin (GRFT) has identified this lectin to be a promising broad-spectrum microbicide. We set out to explore the antiviral properties of a GRFT and carrageenan (CG) combination product against herpes simplex virus 2 (HSV-2) and human papillomavirus (HPV) as well as determine the mechanism of action (MOA) of GRFT against both viruses. We performed the experiments in different cell lines, using time-of-addition and temperature dependence experiments to differentiate inhibition of viral attachment from entry and viral receptor internalization. Surface plasmon resonance (SPR) was used to assess GRFT binding to viral glycoproteins, and immunoprecipitation and immunohistochemistry were used to identify the specific glycoprotein involved. We determined the antiviral activity of GRFT against HSV-2 to be a 50% effective concentration (EC50) of 230 nM and provide the first evidence that GRFT has moderate anti-HPV activity (EC50 = 0.429 to 1.39 μM). GRFT blocks the entry of HSV-2 and HPV into target cells but not the adsorption of HSV-2 and HPV onto target cells. The results of the SPR, immunoprecipitation, and immunohistochemistry analyses of HSV-2 combined suggest that GRFT may block viral entry by binding to HSV-2 glycoprotein D. Cell-based assays suggest anti-HPV activity through α6 integrin internalization. The GRFT-CG combination product but not GRFT or CG alone reduced HSV-2 vaginal infection in mice when given an hour before challenge (P = 0.0352). While GRFT significantly protected mice against vaginal HPV infection when dosed during and after HPV16 pseudovirus challenge (P < 0.026), greater CG-mediated protection was afforded by the GRFT-CG combination for up to 8 h (P < 0.0022). These findings support the development of the GRFT-CG combination as a broad-spectrum microbicide.  相似文献   
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Journal of Neurology - Cerebellar ataxias are a heterogeneous group of disorders of both genetic and non-genetic origin. In sporadic cases, two entities are recognized: multiple system atrophy of...  相似文献   
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Background

It is a challenge in low-resource settings to ensure the availability of complete, timely disease surveillance information. Smartphone applications (apps) have the potential to enhance surveillance data transmission.

Methods

The Central African Republic (CAR) Ministry of Health and Médecins Sans Frontières (MSF) conducted a 15-week pilot project to test a disease surveillance app, Argus, for 20 conditions in 21 health centers in Mambéré Kadéi district (MK 2016). Results were compared to the usual paper-based surveillance in MK the year prior (MK 2015) and simultaneously in an adjacent health district, Nana-Mambére (NM 2016). Wilcoxon rank sum and Kaplan-Meier analyses compared report completeness and timeliness; the cost of the app, and users’ perceptions of its usability were assessed.

Results

Two hundred seventy-one weekly reports sent by app identified 3403 cases and 63 deaths; 15 alerts identified 28 cases and 4 deaths. Median completeness (IQR) for MK 2016, 81% (81–86%), was significantly higher than in MK 2015 (31% (24–36%)), and NM 2016 (52% (48–57)) (p?<?0.01). Median timeliness (IQR) for MK 2016, 50% (39–57%) was also higher than in MK 2015, 19% (19–24%), and NM 2016 29% (24–36%) (p?<?0.01). Kaplan-Meier Survival Analysis showed a significant progressive reduction in the time taken to transmit reports over the 15-week period (p?<?0.01). Users ranked the app’s usability as greater than 4/5 on all dimensions. The total cost of the 15-week pilot project was US$40,575. It is estimated that to maintain the app in the 21 health facilities of MK will cost approximately US$18,800 in communication fees per year.

Conclusions

The app-based data transmission system more than doubled the completeness and timeliness of disease surveillance reports. This simple, low-cost intervention may permit the early detection of disease outbreaks in similar low-resource settings elsewhere.
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