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61.
Lara Saraiva Alanna Silva Reis Jeronimo Marteleto Nunes Rugani Agnes Ant?nia Sampaio Pereira Felipe Dutra Rêgo Ana Cristina Vianna Mariano da Rocha Lima Célia Maria Ferreira Gontijo José Dilermando Andrade Filho 《PloS one》2015,10(8)
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
62.
Karla F.A.S. Silva Miguel Michereff‐Filho Maria E.N. Fonseca José G. Silva‐Filho Ana C.A. Texeira Antônio Williams Moita Jorge B. Torres Rafael Fernández‐Muñoz Leonardo S. Boiteux 《Entomologia Experimentalis et Applicata》2014,151(3):218-230
Advances in tomato breeding for pest resistance have been achieved via gene introgression from wild Solanum (section Lycopersicon) species (Solanaceae). Ninety‐nine F3 families derived from an interspecific cross using as parental lines Solanum lycopersicum L. ‘LAM‐148' (susceptible standard) and Solanum pimpinellifolium L. ‘TO‐937‐15’ (multiple pest resistance accession with type IV glandular trichomes and acylsugar accumulation) were evaluated for their resistance against the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) biotype B in free‐choice and no‐choice tests for oviposition and adult colonization. The parental lines and eight F3 families with contrasting levels of resistance against the whitefly were selected and investigated in additional assays, which included the estimation of trichome densities and foliar acylsugar levels. The F3 families BTR‐302 and BTR‐331 exhibited low amounts of eggs of whitefly and transgressive segregation for type IV glandular trichome density with values greater than that of TO‐937‐15 plants. However, the tested families did not surpass the total foliar acylsugar content found in TO‐937‐15. BTR‐331 exhibited low colonization in the free‐choice test and it was the least preferred F3 family in the no‐choice test. The higher resistance levels of BTR‐331 were associated with a positive combination of higher type IV trichome density and higher acylsugar levels. Some F3 families displayed reduced fruit set due to the presence of flowers with style exertion of the antheridial‐cone. Fruit weight at harvest stage of the selected families (from 4.9 to 14.5 g) was lower than that of LAM‐148 (139.5 g) but higher than that of TO‐937‐15 plants (1.3 g). Therefore, although difficult to reach due to the simultaneous segregation of many polygenic traits, the combination of high B. tabaci resistance levels with superior horticultural traits is feasible. These results confirm TO‐937‐15 as a source of biotype B resistance. From the breeding standpoint, the genetic similarity between S. lycopersicum and S. pimpinellifolium would allow a more efficient resistance introgression by facilitating recombination and minimizing the potentially undesirable linkage drag associated with this trait. 相似文献
63.
Carolina G. Fernandes Guilhian Leipnitz Bianca Seminotti Alexandre U. Amaral Ângela Zanatta Carmen R. Vargas Carlos S. Dutra Filho Moacir Wajner 《Cellular and molecular neurobiology》2010,30(2):317-326
High levels of phenylalanine (Phe) are the biochemical hallmark of phenylketonuria (PKU), a neurometabolic disorder clinically
characterized by severe mental retardation and other brain abnormalities, including cortical atrophy and microcephaly. Considering
that the pathomechanisms leading to brain damage and particularly the marked cognitive impairment in this disease are poorly
understood, in the present study we investigated the in vitro effect of Phe, at similar concentrations as to those found in
brain of PKU patients, on important parameters of oxidative stress in the hippocampus and cerebral cortex of developing rats.
We found that Phe induced in vitro lipid peroxidation (increase of TBA-RS values) and protein oxidative damage (sulfhydryl
oxidation) in both cerebral structures. Furthermore, these effects were probably mediated by reactive oxygen species, since
the lipid oxidative damage was totally prevented by the free radical scavengers α-tocopherol and melatonin, but not by L-NAME,
a potent inhibitor of nitric oxide synthase. Accordingly, Phe did not induce nitric oxide synthesis, but significantly decreased
the levels of reduced glutathione (GSH), the major brain antioxidant defense, in hippocampus and cerebral cortex supernatants.
Phe also reduced the thiol groups of a commercial GSH solution in a cell-free medium. We also found that the major metabolites
of Phe catabolism, phenylpyruvate, phenyllactate and phenylacetate also increased TBA-RS levels in cerebral cortex, but to
a lesser degree. The data indicate that Phe elicits oxidative stress in the hippocampus, a structure mainly involved with
learning/memory, and also in the cerebral cortex, which is severely damaged in PKU patients. It is therefore presumed that
this pathomechanism may be involved at least in part in the severe cognitive deficit and in the characteristic cortical atrophy
associated with dysmyelination and leukodystrophy observed in this disorder. 相似文献
64.
Raquel Cristine Kuhn Francisco Maugeri Filho 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(22):2023-2028
Recent studies have shown that the chromatographic separation of mixtures of monosaccharides and disaccharides may be improved by employing Y zeolites, a procedure which holds promise in the separation of oligosaccharides. In the present study, a column packed with zeolite was employed to study the separation of fructooligosaccharides (FOS). FOS were produced by an enzyme isolated from Rhodotorula sp., which produces GF2 (kestose), GF3 (nystose) and GF4 (frutofuranosyl nystose). The identification and quantification of the sugars were carried out by ion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The separation of fructooligosaccharides was carried out using a fixed bed column packed with Ba2+-exchange Y zeolites. The effects of temperature (40–50 °C), injected volume per bed volume (2.55–7.64%), superficial velocity (0.1–0.15 cm min−1) and eluent composition (40–60% ethanol) were investigated using a fractionary factorial design with separation efficiency as the response. The results showed that the most favorable conditions for the separation of the oligosaccharide–glucose mixture were 60% ethanol as eluent, temperature of 50 °C, superficial velocity of 0.1 cm min−1 and 2.55% injection volume per bed volume of injection mixture, using two columns in series. The values for separation efficiency were 0.60 for oligosaccharide–glucose, 1.00 for oligosaccharide–fructose, 0.22 for oligosaccharide–sucrose, 0.43 for glucose–fructose, 0.82 for glucose–sucrose and 1.23 for fructose–sucrose. 相似文献
65.
Toyama MH Toyama DO Torres VM Pontes GC Farias WR Melo FR Oliveira SC Fagundes FH Diz Filho EB Cavada BS 《The protein journal》2010,29(8):567-571
Low molecular weight fragments of sulfated galactans (Boc-5 and Boc-10) from the red algae Botryocladia occidentalis significantly inhibited Crotalus durissus cascavella sPLA2 enzymatic activity. Equimolar ratios of sPLA2 to Boc-5 or Boc-10 resulted in allosteric inhibition of sPLA2. Under
the conditions tested, we observed that both Boc-5 and Boc-10 strongly decreased edema, myonecrosis, and neurotoxicity induced
by native sPLA2. 相似文献
66.
Saraiva L Andrade Filho JD Silva Sde O Andrade AS Melo MN 《Memórias do Instituto Oswaldo Cruz》2010,105(8):1033-1039
Over the last 20 years, there has been an increase in the number of leishmaniasis cases in Brazil. Belo Horizonte (BH) is one of the most highly populated Brazilian cities that is affected by visceral leishmaniasis (VL). The health services in BH are coordinated by a central nucleus that is subdivided into nine sanitary districts. Historically, the highest level of human VL cases was found in the northeast sanitary district (NSD). The objective of our study was to detect Leishmania infection in the phlebotomine sand flies collected in the NSD by dissection and molecular approaches. Following the occurrence of human VL cases in 2005, entomological captures were performed from July 2006-June 2007. Out of the 245 sand flies dissected, only three Lutzomyia longipalpis spp contained flagellates. The female sand flies were grouped into 120 pools according to date, collection site and species, with approximately 10 individual sand flies in each pool. Subsquently, the DNA was extracted and Leishmania spp and other parasites were detected and identified by polymerase chain reaction (PCR) and PCR-restriction fragment length polymorfism. Leishmania infantum was present in at least 19% of the Lu. longipalpis collected, in 3.8% of the Nyssomiya whitmani collected, in 33.3% of the Evandromiya termitophila collected and in 14.3% of the Nyssomiya intermedia collected. When the females of the cortelezzii complex were compared with each other, 3.2% of the females were infected with Leishmania braziliensis, whereas 3.2% of the females were infected with trypanosomatids. 相似文献
67.
The objective was to improve pregnancy per artificial insemination (P/AI; 35-42 d after AI) in virgin Jersey heifers bred by AI of sex-sorted semen after being detected in estrus. Giving 100 μg of GnRH at first detection of estrus, with AI 12 h later, did not affect P/AI in Experiment I [GnRH = 47.2% (100/212) vs. No GnRH = 51.7% (104/201); P = 0.38] or Experiment II [GnRH = 53.1% (137/258) vs. No GnRH = 48.6% (122/251); P = 0.43]. In these two experiments, estrus detection was done with tail-head chalk or a HeatWatch® system, respectively. In Experiment III, a single insemination dose (2.1 × 106 sperm) 12 h after estrus detection (n = 193), a double dose at 12 h (n = 193), or a double dose involving insemination 12 and 24 h after estrus detection (n = 190) did not affect P/AI (87/193 = 45.1%, 85/193 = 44.0%, and 94/190 = 49.5%, respectively; P = 0.51). However, P/AI was influenced by the number of AI service (First, 115/208 = 55.3%a; Second, 94/204 = 46.1%a; and Third, 57/165 = 34.8%b; P = 0.004). In Experiment IV, the P/AI of heifers inseminated from 12 to 16 h after the onset of estrus (40/106 = 37.7%) was less (P = 0.03) than those inseminated from 16.1 to 20 h (85/164 = 51.8%), and 20.1 to 24 h (130/234 = 55.6%). However, the P/AI for heifers inseminated from 24.1 to 30 h (61/134 = 45.5%) did not differ from that of any other interval. In conclusion, in Jersey heifers inseminated with sex-sorted semen, P/AI was not significantly affected by giving GnRH at detection of estrus or a double insemination dose, but it was higher with AI 16.1 to 24 h vs. 12 to 16 h after the onset of estrus. 相似文献
68.
The subfamily Chloropinae comprises about 442 described species, with only one species recorded from the Brazilian Amazon. The genus Bricelochlorops Paganelli was represented by a unique species from Rio de Janeiro, Brazil. The species Urubambina rufa (Duda) is the only species of the genus Urubambina Paganelli and has been recorded only from Peru. A new species of Bricelochlorops, B. celutae sp. nov., is described here and Urubambina rufa is recorded for the first time in Brazil. Both species were collected in the state of Acre. A key to species of Bricelochlorops is provided. 相似文献
69.
An occupied nest of Epipona media Cooper was discovered and collected in a cabruca (cocoa plantation with native tree cover). This is the first record of E. media from Bahia State. We described the nest structure and compared the adults with the closely related species Epipona tatua Cuvier. 相似文献
70.
Ricardo Imbroisi Filho Alan C. Ochioni Amanda M. Esteves Joo G. B. Leandro Thain M. Demaria Mauro Sola-Penna Patricia Zancan 《Cell death & disease》2021,12(7)
Among the principal causative factors for the development of complications related to aging is a diet rich in fats and sugars, also known as the Western diet. This diet advocates numerous changes that might increase the susceptibility to initiate cancer and/or to create a tissue microenvironment more conducive to the growth of malignant cells, thus favoring the progression of cancer and metastasis. Hypercaloric diets in general lead to oxidative stress generating reactive oxygen species and induce endoplasmic reticulum stress. Our results demonstrate that mice bearing tumors fed with a Western diet presented bigger tumor mass with increased insulin sensitivity in these tissues. Several markers of insulin signaling, such as AKT phosphorylation and mTOR pathway, are promoted in tumors of Western diet-fed animals. This process is associated with increased macrophage infiltration, activation of unfolded protein response pathway, and initiation of epithelial–mesenchymal transition (EMT) process in these tumor tissues. Summing up, we propose that the Western diet accelerates the aging-related processes favoring tumor development.Subject terms: Melanoma, TOR signalling, Mechanisms of disease, Ageing 相似文献