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151.
In the present study, we have described and compared both the number and the types of the mistakes that were made during reading of the Ishihara plates by 3,926 students attending the secondary schools in the province of Cosenza (Calabria, Southern Italy) and by 546 Calabrian university students all without colour-blindness. There were no qualitative differences in the types of mistakes made by the two groups of subjects during their reading of the Ishihara plates. Moreover, we have reported both the mean frequencies and types of colour-blindness in only the province of Cosenza. During this study, it was shown that the ishihara test is reliable during screenings for the diagnosis of colour vision deficiencies, as shown by some previous investigations.  相似文献   
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BackgroundThe obligate intracellular protozoan Trypanosoma cruzi is the causative agent of Chagas disease, a neglected illness affecting millions of people in Latin America that recently entered non-endemic countries through immigration, as a consequence of globalization. The chemotherapy for this disease is based mainly on benznidazole and nifurtimox, which are very efficient nitroderivatives against the acute stage but present limited efficacy during the chronic phase. Our group has been studying the trypanocidal effects of naturally occurring quinones and their derivatives, and naphthoimidazoles derived from β-lapachone N1, N2 and N3 were the most active. To assess the molecular mechanisms of action of these compounds, we applied proteomic techniques to analyze treated bloodstream trypomastigotes, which are the clinically relevant stage of the parasite.Conclusion/SignificanceOur results point to different modes of action for N1, N2 and N3, which indicate a great variety of metabolic pathways involved and allow for novel perspectives on the development of trypanocidal agents.  相似文献   
154.
We investigated the role of different TLRs and MyD88 in host resistance to infection and malaria pathogenesis. TLR2(-/-), TLR4(-/-), TLR6(-/-), TLR9(-/-) or CD14(-/-) mice showed no change in phenotypes (parasitemia, body weight and temperature) when infected with Plasmodium chabaudi chabaudi (AS). MyD88(-/-) mice displayed comparable ability to wild type animals in controlling and clearing parasitemia. Importantly, MyD88(-/-) mice exhibited impaired production of TNF-alpha and IFN-gamma as well as attenuated symptoms, as indicated by changes in body weight and temperature during parasitemia. Consistently, CD11b(+) monocytes and CD11c(+) dendritic cells from infected MyD88(-/-) mice were shown impaired for production of pro-inflammatory cytokines, and in initiating CD4(+) T cell responses. Importantly, the inhibition of T cell activation with anti-CD134L, mostly inhibited IFN-gamma, partially inhibited TNF-alpha production, and protected the animals from malaria symptoms. Our findings suggest that MyD88 and possibly its associated TLRs expressed by dendritic cells play an important role in pro-inflammatory responses, T cell activation, and pathogenesis of malaria, but are not critical for the immunological control of the erythrocytic stage of P. chabaudi.  相似文献   
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Antibodies play an ever more prominent role in basic research as well as in the biotechnology and pharmaceutical sectors. Characterizing their epitopes, that is, the region that they recognize on their target molecule, is useful for purposes ranging from molecular biology research to vaccine design and intellectual property protection. Solution NMR spectroscopy is ideally suited to the atomic level characterization of intermolecular interfaces and, as a consequence, to epitope discovery. Here, we illustrate how NMR epitope mapping can be used to rapidly and accurately determine protein antigen epitopes. The basic concept is that differences in the NMR signal of an antigen free or bound by an antibody will identify epitope residues. NMR epitope mapping provides more detailed information than mutagenesis or peptide mapping and can be much more rapid than X‐ray crystallography. Advantages and drawbacks of this technique are discussed together with practical considerations. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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There is a constant need to improve antiretrovirals against HIV since therapy is limited by cost, side effects and the emergence of drug resistance. Kudzu is a climbing vine from which the root extract (Pueraria lobata), rich in isoflavones and saponins, has long been used in traditional Chinese medicine for a variety of purposes, from weight loss to alcoholism prevention. Here we show that Kudzu root extract significantly inhibits HIV-1 entry into cell lines, primary human CD4+T lymphocytes and macrophages, without cell-associated toxicity. Specifically, Kudzu inhibits the initial attachment of the viral particle to the cell surface, a mechanism that depends on the envelope glycoprotein gp120 but is independent from the HIV-1 cell receptor CD4 and co-receptors CXCR4/CCR5. This activity seems selective to lentiviruses since Kudzu inhibits HIV-2 and simian immunodeficiency virus, but does not interfere with Hepatitis C, Influenza, Zika Brazil and adenovirus infection. Importantly, depending on the dose, Kudzu can act synergistically or additively with the current antiretroviral cocktails against HIV-1 and can block   viruses resistant to the fusion inhibitor Enfuvirtide. Together our results highlight Kudzu’s root extract value as a supplement to current antiretroviral therapy against HIV.
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160.

Background

The significant increase in the popularity of breast augmentation surgeries has led to an increase in the number and types of complications; among these is the postoperative occurrence of Striae Distensae (SD). The objective of this study was to investigate the incidence of SD and describing its occurrence in association with age, breast implant volume, history of SD, history of pregnancies and breastfeeding, body mass index (BMI), changes in postoperative weight, smoking habits, and use of oral contraceptives.

Methods

A cohort study was conducted and the patient data from a specific social group that underwent augmentation mammaplasty with silicone breast implants in a private clinic was analyzed.

Results

563 patients entered the cohort, while 538 completed the study. The SD incidence was 7.06%. The risk was almost the double at 22–28 years of age and triple in women of 21 years of age or less. The women who did not use oral contraceptives were 2.59 times more likely of developing SD. A higher incidence of SD was observed among those with normal or low BMI values, smokers, and in those who had implants larger than 300 ml.

Conclusions

Young age, larger implant volumes, smoking, and normal or low BMI values were the risk factors responsible for the development of SD; while using oral contraceptives was found to be a protective factor.  相似文献   
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