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Mannose‐capped lipoarabinomannan (ManLAM) is considered an important virulence factor of Mycobacterium tuberculosis. However, while mannose caps have been reported to be responsible for various immunosuppressive activities of ManLAMobserved in vitro, there is conflicting evidence about their contribution to mycobacterial virulence in vivo. Therefore, we used Mycobacterium bovis BCG and M. tuberculosis mutants that lack the mannose cap of LAM to assess the role of ManLAM in the interaction of mycobacteria with the host cells, to evaluate vaccine‐induced protection and to determine its importance in M. tuberculosis virulence. Deletion of the mannose cap did not affect BCG survival and replication in macrophages, although the capless mutant induced a somewhat higher production of TNF. In dendritic cells, the capless mutant was able to induce the upregulation of co‐stimulatory molecules and the only difference we detected was the secretion of slightly higher amounts of IL‐10 as compared to the wild type strain. In mice, capless BCG survived equally well and induced an immune response similar to the parental strain. Furthermore, the efficacy of vaccination against a M. tuberculosis challenge in low‐dose aerosol infection models in mice and guinea pigs was not affected by the absence of the mannose caps in the BCG. Finally, the lack of the mannose cap in M. tuberculosis did not affect its virulence in mice nor its interaction with macrophages in vitro. Thus, these results do not support a major role for the mannose caps of LAM in determining mycobacterial virulence and immunogenicity in vivo in experimental animal models of infection, possibly because of redundancy of function.  相似文献   
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Novelty search is a recent artificial evolution technique that challenges traditional evolutionary approaches. In novelty search, solutions are rewarded based on their novelty, rather than their quality with respect to a predefined objective. The lack of a predefined objective precludes premature convergence caused by a deceptive fitness function. In this paper, we apply novelty search combined with NEAT to the evolution of neural controllers for homogeneous swarms of robots. Our empirical study is conducted in simulation, and we use a common swarm robotics task—aggregation, and a more challenging task—sharing of an energy recharging station. Our results show that novelty search is unaffected by deception, is notably effective in bootstrapping evolution, can find solutions with lower complexity than fitness-based evolution, and can find a broad diversity of solutions for the same task. Even in non-deceptive setups, novelty search achieves solution qualities similar to those obtained in traditional fitness-based evolution. Our study also encompasses variants of novelty search that work in concert with fitness-based evolution to combine the exploratory character of novelty search with the exploitatory character of objective-based evolution. We show that these variants can further improve the performance of novelty search. Overall, our study shows that novelty search is a promising alternative for the evolution of controllers for robotic swarms.  相似文献   
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Capsicum species belong to the Solanaceae family and have great social, economic and agronomical significance. The present research presents data on the isolation and characterization of Capsicum chinense Jacq. peptides which were scrutinized in relation to their toxicity towards a diverse set of yeast species. The protein extract was separated with C18 reverse-phase chromatography in high performance liquid chromatography, resulting in three different peptide enriched fractions (PEFs) termed PEF1, PEF2 and PEF3. Tricine-SDS-PAGE of the PEF2 revealed peptides with molecular masses of approximately 5.0 and 8.5 kDa. These PEFs also exhibited strong antifungal activity against different yeasts. In the presence of the PEF2, Candida tropicalis exhibited morphological changes, including cellular agglomeration and formation of pseudohyphae. Determined N-terminal sequences of PEF2 and PEF3 were proven to be highly homologous to serine proteinase inhibitors, when analysed by comparative database sequence tools. For this reason were performed protease inhibitory activity assay. The PEFs displayed high inhibitory activity against trypsin and low inhibitory activity against chymotrypsin. PEF2 and PEF3 were considerably unsusceptible to a broad interval of pH and temperatures. Due to the myriad of application of Proteinase inhibitors (PIs) in fields ranging from plant protection against pathogens and pests to medicine such as in cancer and virus replication inhibition, the discovery of new PIs with new properties are of great interest.  相似文献   
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Aedes aegypti has developed evolution-driven adaptations for surviving in the domestic human habitat. Several trap models have been designed considering these strategies and tested for monitoring this efficient vector of Dengue. Here, we report a real-scale evaluation of a system for monitoring and controlling mosquito populations based on egg sampling coupled with geographic information systems technology. The SMCP-Aedes, a system based on open technology and open data standards, was set up from March/2008 to October/2011 as a pilot trial in two sites of Pernambuco -Brazil: Ipojuca (10,000 residents) and Santa Cruz (83,000), in a joint effort of health authorities and staff, and a network of scientists providing scientific support. A widespread infestation by Aedes was found in both sites in 2008–2009, with 96.8%–100% trap positivity. Egg densities were markedly higher in SCC than in Ipojuca. A 90% decrease in egg density was recorded in SCC after two years of sustained control pressure imposed by suppression of >7,500,000 eggs and >3,200 adults, plus larval control by adding fishes to cisterns. In Ipojuca, 1.1 million mosquito eggs were suppressed and a 77% reduction in egg density was achieved. This study aimed at assessing the applicability of a system using GIS and spatial statistic analysis tools for quantitative assessment of mosquito populations. It also provided useful information on the requirements for reducing well-established mosquito populations. Results from two cities led us to conclude that the success in markedly reducing an Aedes population required the appropriate choice of control measures for sustained mass elimination guided by a user-friendly mosquito surveillance system. The system was able to support interventional decisions and to assess the program’s success. Additionally, it created a stimulating environment for health staff and residents, which had a positive impact on their commitment to the dengue control program.  相似文献   
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Molecular Biology Reports - Molecular detection of Giardia duodenalis by polymerase chain reaction (PCR) is difficult in faecal samples due to inhibitors that contaminate DNA preparations, or due...  相似文献   
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Familial hypercholesterolemia (FH) is an autosomal dominant genetic disease characterized by high levels of low-density lipoprotein-cholesterol (LDLc), associated to premature cardiovascular disease. The detection of the variants related to FH is important to improve the early diagnosis in probands / index-cases (ICs) and their relatives. We included ICs with FH and their relatives, living in a small region of Minas Gerais state-Brazil, which were classified according to Dutch Lipid Clinic Network Criteria (DLCNC) and submitted to sequencing of genes related to FH (LDLR, APOB, PCSK9, LDLRAP1, LIPA, STAP1, APOE, ABCG5 e ABCG8). In a total of 143 subjects (32 ICs and 111 relatives), eight variants were identified in 91 individuals. From these variants, five were in LDLR [p.(Asp224Asn), p.(Ser854Gly), p.(Cys34Arg), p.(Asp601His), deletion of exon15 in LDLR)], one in APOB [p.(Met499Val)], one in PCSK9 [p.(Arg237Trp)] and one in APOE [p.(Pro28Leu)] genes. The variants were detected in 100% of those subjects classified as definitive, 87% as probable and 69% as possible FH cases based on DLCNC. The LDLc level was higher in individuals with corneal arch and xanthomas or xanthelasmas, as well as in pathogenic or probably pathogenic variants carriers. This study showed higher frequency of LDLR gene variants compared to other genes related to LDL metabolism in individuals with FH in Minas Gerais – Brazil and the presence of FH in relatives without previous diagnosis. Our data reinforce the importance of molecular and clinical evaluation of FH relatives in order to early diagnosis the FH, as well as cardiovascular diseases prevention.

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Objective: To evaluate the efficacy of electric and conventional toothbrushes for a group of elderly individuals. Background: Although the electric toothbrush has been recommended for elderly individuals, there had previously never been a study regarding its efficacy. Material and methods: Sixty independent elders of both genders with different oral conditions from the Center Adult Day Vitória, Espírito Santo, Brazil, were randomly divided into two groups of 30 individuals. One group received the Oral B CrossAction Power electric toothbrush, whereas the other received a conventional Bitufo Class 32 soft toothbrush to perform oral hygiene. The bacterial plaque index (O’Leary Plaque Index) and DMFT index were assessed as a measure of oral hygiene and oral health. The data were analysed using the Shapiro–Wilk, Mann–Whitney and Wilcoxon tests. Results: The results of the efficacy of the Oral B Cross Action Power electric toothbrush demonstrated that on the 7th and 15th days, the bacterial plaque indexes were 24.91 ± 12.81 and 22.11 ± 14.46, respectively, which corresponds to a 50.24% removal of bacterial plaque on the 7th and 55.83% on the 15th days. Although the electric toothbrush removed more bacterial plaque than the conventional toothbrush, the difference was not statistically significant. Conclusion: Both the conventional and the electric toothbrushes were effective in removing bacterial plaque within the elderly group. More studies are necessary to test the efficacy of electric toothbrushes in relation to conventional toothbrushes for elderly patients.  相似文献   
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