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21.
22.
Brazil is one of the most important endemic areas for leishmaniasis worldwide. Protected areas that are tourist attractions likely present an important risk of transmission of cutaneous leishmaniasis (CL). Furthermore, with the geographical expansion of visceral leishmaniasis (VL), several studies have recorded the occurrence of its vector, Lutzomyia longipalpis, and cases of human and canine VL in such tourist areas. The Parque Estadual do Sumidouro is an environmentally protected area located in the Brazilian Cerrado biome and in an important area endemic for leishmaniasis in the state of Minas Gerais. The purpose of this study was to monitor the sand fly fauna in areas of tourist activity in the park. Sampling was performed every month, from September 2011 to August 2013, using CDC light traps at six sites of differing environmental characteristics. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A total of 4,675 sand fly specimens of 25 species belonging to nine genera were collected. The most abundant species were Micropygomyia quinquefer, Lutzomyia renei and Pintomyia pessoai, although only Pi. pessoai is implicated in the transmission of Leishmania braziliensis. The species accumulation curve reached saturation on the 16th sampling event. Species richness, diversity and evenness differed among the sampled areas. The seasonal curve was not determined by a single unique species, and no single species was the most abundant in all environments sampled. The main vector of Leishmania (Leishmania) infantum, Lutzomyia longipalpis, accounted for only 5.35% of the specimens collected. Proven or suspected vectors of Leishmania (Viannia) braziliensis were recorded, and one female of the cortellezzii complex tested positive for Le. braziliensis DNA. Even with a low infection rate (0.62%), these data indicate the circulation of the parasite and reinforce the need for entomological and epidemiological surveillance in the park and its surroundings.  相似文献   
23.
Bacterial and fungal infections and the emerging multidrug resistance are driving interest in fighting these microorganisms with natural products, which have generally been considered complementary to pharmacological therapies. Phlorotannins are polyphenols restricted to brown seaweeds, recognized for their biological capacity. This study represents the first research on the antibacterial, antifungal, anti-inflammatory and antioxidant activity of phlorotannins purified extracts, which were obtained from ten dominant brown seaweeds of the occidental Portuguese coast.Phlorotannins content was determined by the specific dimethoxybenzaldehyde (DMBA) method and a yield between 75 and 969 mg/Kg phloroglucinol units (dry matter) was obtained. Fucus spiralis ranked first, followed by three Cystoseira species. The anti-inflammatory potential of the purified extracts was assessed via inhibitory effect on nitric oxide (NO) production by lipopolysaccharide-stimulated RAW 264.7 macrophage cells, Cystoseira tamariscifolia being the one showing promising activity for the treatment of inflammation. NO scavenging ability was also addressed in cell free systems, F. spiralis being the species with highest capacity. The antimicrobial potential of the extracts was checked against five Gram-positive and four Gram-negative bacteria and three fungi strains, that commonly colonize skin and mucosa and are responsible for food contamination. The different extracts were more effective against Gram-positive bacteria, Staphylococcus epidermidis being the most susceptible species. Concerning antifungal activity, Trichophyton rubrum was the most sensitive species.Although the molecular mechanisms underlying these properties remain poorly understood, the results obtained turn phlorotannins purified extracts a novel and potent pharmacological alternative for the treatment of a wide range of microbial infections, which usually also present an inflammatory component. In addition to the biological properties demonstrated herein, phlorotannins extracts may also be preferred, in order to avoid side effects and allergic reactions commonly associated with synthetic drugs.  相似文献   
24.
The MAGE-C1/CT7 encodes a cancer/testis antigen (CTA), is located on the chromosomal region Xq26-27 and is highly polymorphic in humans. MAGE-C1/CT7 is frequently expressed in multiple myeloma (MM) that may be a potential target for immunotherapy in this still incurable disease. MAGEC1/CT7 expression is restricted to malignant plasma cells and it has been suggested that MAGE-C1/CT7 might play a pathogenic role in MM; however, the exact function this protein in the pathophysiology of MM is not yet understood. Our objectives were (1) to clarify the role of MAGE-C1/CT7 in the control of cellular proliferation and cell cycle in myeloma and (2) to evaluate the impact of silencing MAGE-C1/CT7 on myeloma cells treated with bortezomib. Myeloma cell line SKO-007 was transduced for stable expression of shRNA-MAGE-C1/CT7. Downregulation of MAGE-C1/CT7 was confirmed by real time quantitative PCR and western blot. Functional assays included cell proliferation, cell invasion, cell cycle analysis and apoptosis. Western blot showed a 70-80% decrease in MAGE-C1/CT7 protein expression in inhibited cells (shRNA-MAGE-C1/CT7) when compared with controls. Functional assays did not indicate a difference in cell proliferation and DNA synthesis when inhibited cells were compared with controls. However, we found a decreased percentage of cells in the G2/M phase of the cell cycle among inhibited cells, but not in the controls (p<0.05). When myeloma cells were treated with bortezomib, we observed a 48% reduction of cells in the G2/M phase among inhibited cells while controls showed 13% (empty vector) and 9% (ineffective shRNA) reduction, respectively (p<0.01). Furthermore, inhibited cells treated with bortezomib showed an increased percentage of apoptotic cells (Annexin V+/PI-) in comparison with bortezomib-treated controls (p<0.001). We found that MAGE-C1/CT7 protects SKO-007 cells against bortezomib-induced apoptosis. Therefore, we could speculate that MAGE-C1/CT7 gene therapy could be a strategy for future therapies in MM, in particular in combination with proteasome inhibitors.  相似文献   
25.
Mesenchymal stem cells (MSCs) are viewed as safe, readily available and promising adult stem cells, which are currently used in several clinical trials. Additionally, their soluble-factor secretion and multi-lineage differentiation capacities place MSCs in the forefront of stem cell types with expected near-future clinical applications. In the present work MSCs were isolated from the umbilical cord matrix (Wharton''s jelly) of human umbilical cord samples. The cells were thoroughly characterized and confirmed as bona-fide MSCs, presenting in vitro low generation time, high proliferative and colony-forming unit-fibroblast (CFU-F) capacity, typical MSC immunophenotype and osteogenic, chondrogenic and adipogenic differentiation capacity. The cells were additionally subjected to an oligodendroglial-oriented step-wise differentiation protocol in order to test their neural- and oligodendroglial-like differentiation capacity. The results confirmed the neural-like plasticity of MSCs, and suggested that the cells presented an oligodendroglial-like phenotype throughout the differentiation protocol, in several aspects sharing characteristics common to those of bona-fide oligodendrocyte precursor cells and differentiated oligodendrocytes.  相似文献   
26.
A rapid and simple method for the purification of amastigotes of Trypanosoma cruzi from spleens of infected mice is described. A protein A-Scpharose 4B immunoadsorbent column bound with antisera to epimastigotes of T. cruzi was used to purify the tissue forms of this parasite. Host cells and debris are not retained, and parasites can be eluted in high yields and purity. Studies of surface glycoproteins and glycolipids of the purified amastigotes with 18 lectins of various specificities revealed the presence on the parasites of receptors for N-acetylglucosamine, N-acetylgalactosamine, D-galactose, and D-mannose binding lectins.  相似文献   
27.
The aim of this work was to use in vivo models to evaluate the analgesic and anti-inflammatory activities of ursolic acid (UA) and oleanoic acid (OA), the major compounds isolated as an isomeric mixture from the crude methylene chloride extract of Miconia albicans aerial parts in an attempt to clarify if these compounds are responsible for the analgesic properties displayed by this plant. Ursolic acid inhibited abdominal constriction in a dose-dependent manner, and the result obtained at a content of 40 mg kg(-1) was similar to that produced by administration of acetylsalicylic acid at a content of 100 mg kg(-1). Both acids reduced the number of paw licks in the second phase of the formalin test, and both of them displayed a significant anti-inflammatory effect at a content of 40 mg kg(-1). It is noteworthy that the administration of the isolated mixture, containing 65% ursolic acid/35% oleanolic acid, did not display significant analgesic and anti-inflammatory activities. On the basis of the obtained results, considering that the mixture of UA and OA was poorly active, it is suggested that other compounds, rather than UA and OA, should be responsible for the evaluated activities in the crude extract, since the crude extract samples displayed good activities.  相似文献   
28.
The increasing interest in the preservation of the environment and the health of consumers is changing production methods and food consumption habits. Functional foods are increasingly demanded by consumers because they contain bioactive compounds involved in health protection. In this sense biofertilization using plant probiotics is a reliable alternative to the use of chemical fertilizers, but there are few studies about the effects of plant probiotics on the yield of functional fruits and, especially, on the content of bioactive compounds. In the present work we reported that a strain of genus Phyllobacterium able to produce biofilms and to colonize strawberry roots is able to increase the yield and quality of strawberry plants. In addition, the fruits from plants inoculated with this strain have significantly higher content in vitamin C, one of the most interesting bioactive compounds in strawberries. Therefore the use of selected plant probiotics benefits the environment and human health without agronomical losses, allowing the production of highly functional foods.  相似文献   
29.
The purpose of this study was to compare the acute effects of general, specific and combined warm-up (WU) on explosive performance. Healthy male (n = 10) subjects participated in six WU protocols in a crossover randomized study design. Protocols were: passive rest (PR; 15 min of passive rest), running (Run; 5 min of running at 70% of maximum heart rate), stretching (STR; 5 min of static stretching exercise), jumping [Jump; 5 min of jumping exercises – 3x8 countermovement jumps (CMJ) and 3x8 drop jumps from 60 cm (DJ60)], and combined (COM; protocols Run+STR+Jump combined). Immediately before and after each WU, subjects were assessed for explosive concentric-only (i.e. squat jump – SJ), slow stretch-shortening cycle (i.e. CMJ), fast stretch-shortening cycle (i.e. DJ60) and contact time (CT) muscle performance. PR significantly reduced SJ performance (p =0.007). Run increased SJ (p =0.0001) and CMJ (p =0.002). STR increased CMJ (p =0.048). Specific WU (i.e. Jump) increased SJ (p =0.001), CMJ (p =0.028) and DJ60 (p =0.006) performance. COM increased CMJ performance (p =0.006). Jump was superior in SJ performance vs. PR (p =0.001). Jump reduced (p =0.03) CT in DJ60. In conclusion, general, specific and combined WU increase slow stretch-shortening cycle (SSC) muscle performance, but only specific WU increases fast SSC muscle performance. Therefore, to increase fast SSC performance, specific fast SSC muscle actions must be included during the WU.  相似文献   
30.
The seroprevalence of human T cell leukemia virus type 1 (HTLV-1) infection was investigated in Brazilians (570): native inhabitants (298) and descendants from Japanese (272) living in Recife and its neighborhoods—North-east of Brazil. Furthermore, polytransfused renal transplanted patients (54) were also examined for the serological status to this virus. The seropositivity to HTLV-1, screened by enzyme-linked immunosorbent assay (ELISA), was low: 1.34% for the local population and 0.73% for the descendants from Japanese. However, the seropositivity for the renal transplanted patients was found to be 11.1%. This higher value suggests that this retrovirus infection seems to be of importance in this clinical condition.  相似文献   
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