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991.
Francisco Meijide Juan V. Trillo Santiago de Frutos Luciano Galantini Nicolae Viorel Pavel Victor H. Soto Aida Jover José Vázquez Tato 《Steroids》2013,78(2):247-254
The crystal structure of three head-to-head dimers (having two cholic acid or deoxycholic acid units) linked at carbon atoms C3 by aromatic or alkyl bridges is studied. An internal coordinates system is necessary for describing the relative orientation in the space of the two bile acid residues. Five angles (three torsion and two common ones) are necessary for defining the relative position of both steroid residues in space. Carbon atoms C3 (which always carries a α-hydroxy group in natural bile acids), and C10 and C13 (which always carry β-methyl groups) of each steroid residue are suitable for this purpose. Furthermore, the distance between each C3 carbon atoms of both steroid residues will allow one to locate the steroids in space. The three dimers selected provide a large range of values for these angles. The packing, hydrogen bond network, and location of guest in the three crystals are discussed. 相似文献
992.
Elena Pérez-Vega Noemí Trabanco Ana Campa Juan José Ferreira 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(6):1503-1512
Powdery mildew (PM) is a serious disease in many legume species, including the common bean (Phaseolus vulgaris L.). This study investigated the genetic control behind resistance reaction to PM in the bean genotype, Cornell 49242. The results revealed evidence supporting a qualitative mode of inheritance for resistance and the involvement of two independent genes in the resistance reaction. The location of these resistance genes was investigated in a linkage genetic map developed for the XC RIL population. Contingency tests revealed significant associations for 28 loci out of a total of 329 mapped loci. Fifteen were isolated or formed groups with less than two loci. The thirteen remaining loci were located at three regions in linkage groups Pv04, Pv09, and Pv11. The involvement of Pv09 was discarded due to the observed segregation in the subpopulation obtained from the Xana genotype for the loci located in this region. In contrast, the two subpopulations obtained from the Xana genotype for the BM161 locus, linked to the Co-3/9 anthracnose resistance gene (Pv04), and from the Xana genotype for the SCAReoli locus, linked to the Co-2 anthracnose resistance gene (Pv11), exhibited monogenic segregations, suggesting that both regions were involved in the genetic control of resistance. A genetic dissection was carried out to verify the involvement of both regions in the reaction to PM. Two resistant recombinant lines were selected, according to their genotypes, for the block of loci included in the Co-2 and Co-3/9 regions, and they were crossed with the susceptible parent, Xana. Linkage analysis in the respective F2 populations supported the hypothesis that a dominant gene (Pm1) was located in the linkage group Pv11 and another gene (Pm2) was located in the linkage group Pv04. This is the first report showing the localization of resistance genes against powdery mildew in Phaseolus vulgaris and the results offer the opportunity to increase the efficiency of breeding programs by means of marker-assisted selection. 相似文献
993.
Molly Sharlach Douglas Dahlbeck Lily Liu Joshua Chiu José M. Jiménez-Gómez Seisuke Kimura Daniel Koenig Julin N. Maloof Neelima Sinha Gerald V. Minsavage Jeffrey B. Jones Robert E. Stall Brian J. Staskawicz 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(3):601-609
The RXopJ4 resistance locus from the wild accession Solanum pennellii (Sp) LA716 confers resistance to bacterial spot disease of tomato (S. lycopersicum, Sl) caused by Xanthomonas perforans (Xp). RXopJ4 resistance depends on recognition of the pathogen type III effector protein XopJ4. We used a collection of Sp introgression lines (ILs) to narrow the RXopJ4 locus to a 4.2-Mb segment on the long arm of chromosome 6, encompassed by the ILs 6-2 and 6-2-2. We then adapted or developed a collection of 14 molecular markers to map on a segregating F2 population from a cross between the susceptible parent Sl FL8000 and the resistant parent RXopJ4 8000 OC7. In the F2 population, a 190-kb segment between the markers J350 and J352 cosegregated with resistance. This fine mapping will enable both the identification of candidate genes and the detection of resistant plants using cosegregating markers. The RXopJ4 resistance gene(s), in combination with other recently characterized genes and a quantitative trait locus (QTL) for bacterial spot disease resistance, will likely be an effective tool for the development of durable resistance in cultivated tomato. 相似文献
994.
995.
José Rodrigues Coura Pedro Albajar Vi?as Lucia Maria Brum-Soares Andréa Silvestre de Sousa Sérgio Salles Xavier 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1009-1013
A case-control study on the morbidity of Chagas heart disease was carried out in the
municipality of Barcelos in the microregion of the Rio Negro, state of Amazonas. One
hundred and six individuals, who were serologically positive for Trypanosoma
cruzi infection, as confirmed by at least two techniques with different
principles, were matched according to age and sex with an equal number of
seronegative individuals. The cases and controls were evaluated using an
epidemiological questionnaire and clinical, electrocardiograph and echocardiograph
examinations. In the seroepidemiological evaluation, 62% of the interviewees
recognised triatomines and most of them confirmed that they had seen these insects in
the piassava plantations of the riverside communities of the Negro River tributaries.
Of the seropositive patients, 25.8% affirmed that they had been stung by the
triatomines and 11.7% denied having been stung. The principal clinical manifestations
of the seropositive individuals were palpitations, chest pain and dyspnoea upon
effort. Cardiac auscultation revealed extrasystoles, bradycardia and systolic
murmurs. The electrocardiographic alterations were ventricular extrasystoles, left
and right bundle branch block, atrioventricular block and primary T wave alterations.
The echocardiogram was altered in 22.6% of the seropositive individuals and in 8.5%
of the seronegative individuals. 相似文献
996.
One of the most common environmental stressors is a shortage or suboptimal quality of food, thus all animals deal with periods of starvation. In the present study we examine variation in starvation resistance, longevity and body lipid content and the correlations between traits along an environmental gradient using isofemale lines recently derived from natural populations of Drosophila melanogaster from South America. The use of isofemale lines and controlled rearing laboratory conditions allows us to investigate within and among population components of genetic variation and the potential associations among starvation resistance, longevity and body lipid content. All these traits were analyzed separately in females and males, improving our understanding of sexual dimorphism. Our results revealed significant differences among populations in starvation resistance and longevity. Actually, the opposing latitudinal cline detected for starvation resistance suggests that natural selection played an essential role in shaping the pattern of geographic variation in this trait. Moreover, we also detected a positive relationship between starvation resistance and body lipid content in both sexes, providing evidence for a physiological and/or evolutionary association between these traits. Conversely, starvation resistance was not correlated with longevity indicating that these traits might be enabled to evolve independently. Finally, our study reveals that there is abundant within population genetic variation for all traits that may be maintained by sex-specific effects. 相似文献
997.
Félix Javier León Molinet Julia Sonia Ampuero Rodrigo Diniz Costa Elza Ferreira Noronha Gustavo Adolfo Sierra Romero 《Memórias do Instituto Oswaldo Cruz》2013,108(3):293-296
The aim of this study was to evaluate the specificity of a rapid immunochromatographic test that was developed to detect antibodies against the rK39 antigen for the diagnosis of visceral leishmaniasis (VL). This evaluation was performed using sera from patients with a confirmed diagnosis of active cutaneous leishmaniasis. The sera from 272 patients with a confirmed diagnosis of localised cutaneous leishmaniasis (CL) who resided in an area endemic for Leishmania braziliensis in Brazil were obtained before the initiation of antileishmanial treatment. Kalazar Detect(r)(InBios, Seattle, WA) recombinant K39 antigen-based immunochromatographic strips were used according to the manufacturer''s instructions. The test results were evaluated independently by two examiners in sequential order. The positive controls for the test included five serum samples from five patients with parasitologically confirmed diagnosis of VL caused by Leishmania infantum in Brazil. Overall, 100% of the samples obtained from patients with CL were negative, confirming the absence of a serological cross-reaction for individuals with cutaneous disease when these patients were evaluated using the rapid test. The lack of a cross-reaction in patients who were infected by parasites of the same genus highlights the specificity of the rK39 antigen for the diagnosis of VL in areas with the sympatric circulation of L. braziliensis and L. infantum. 相似文献
998.
999.
Application of Hazard Analysis and Critical Control Points (HACCP) to the Cultivation Line of Mushroom and Other Cultivated Edible Fungi 总被引:1,自引:0,他引:1
José E. Pardo Vinícius Reis de Figueirêdo Manuel Álvarez-Ortí Diego C. Zied Jesús A. Peñaranda Eustáquio Souza Dias Arturo Pardo-Giménez 《Indian journal of microbiology》2013,53(3):359-369
The Hazard analysis and critical control points (HACCP) is a preventive system which seeks to ensure food safety and security. It allows product protection and correction of errors, improves the costs derived from quality defects and reduces the final overcontrol. In this paper, the system is applied to the line of cultivation of mushrooms and other edible cultivated fungi. From all stages of the process, only the reception of covering materials (stage 1) and compost (stage 3), the pre-fruiting and induction (step 6) and the harvest (stage 7) have been considered as critical control point (CCP). The main hazards found were the presence of unauthorized phytosanitary products or above the permitted dose (stages 6 and 7), and the presence of pathogenic bacteria (stages 1 and 3) and/or heavy metals (stage 3). The implementation of this knowledge will allow the self-control of their productions based on the system HACCP to any plant dedicated to mushroom or other edible fungi cultivation. 相似文献
1000.
José Rodrigues Coura 《Memórias do Instituto Oswaldo Cruz》2013,108(8):962-967
From an epidemiological point of view, Chagas disease and its reservoirs and vectors
can present the following characteristics: (i) enzooty, maintained by wild animals
and vectors, with broad occurrence from southern United States of America (USA) to
southern Argentina and Chile (42ºN 49ºS), (ii) anthropozoonosis, when man invades the
wild ecotope and becomes infected with Trypanosoma cruzi from wild
animals or vectors or when the vectors and wild animals, especially marsupials,
invade the human domicile and infect man, (iii) zoonosis-amphixenosis and exchanged
infection between animals and humans by domestic vectors in endemic areas and (iv)
zooanthroponosis, infection that is transmitted from man to animals, by means of
domestic vectors, which is the rarest situation in areas endemic for Chagas disease.
The characteristics of Chagas disease as an enzooty of wild animals and as an
anthropozoonosis are seen most frequently in the Brazilian Amazon and in the
Pan-Amazon region as a whole, where there are 33 species of six genera of wild
animals: Marsupialia, Chiroptera, Rodentia, Edentata (Xenarthra), Carnivora and
Primata and 27 species of triatomines, most of which infected with T.
cruzi . These conditions place the resident populations of this area or
its visitors - tourists, hunters, fishermen and especially the people whose
livelihood involves plant extraction - at risk of being affected by Chagas disease.
On the other hand, there has been an exponential increase in the acute cases of
Chagas disease in that region through oral transmission of T. cruzi
, causing outbreaks of the disease. In four seroepidemiological surveys that were
carried out in areas of the microregion of the Negro River, state of Amazonas, in
1991, 1993, 1997 and 2010, we found large numbers of people who were serologically
positive for T. cruzi infection. The majority of them and/or their
relatives worked in piassava extraction and had come into contact with and were stung
by wild triatomines in that area. Finally, a characteristic that is greatly in
evidence currently is the migration of people with Chagas disease from endemic areas
of Latin America to non-endemic countries. This has created a new dilemma for these
countries: the risk of transmission through blood transfusion and the onus of
controlling donors and treating migrants with the disease. As an enzooty of wild
animals and vectors, and as an anthropozoonosis, Chagas disease cannot be eradicated,
but it must be controlled by transmission elimination to man. 相似文献