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101.
Pimentel C Van Der Straeten D Pires E Faro C Rodrigues-Pousada C 《The FEBS journal》2007,274(10):2523-2539
Cardosin A and cardosin B are two aspartic proteases mainly found in the pistils of cardoon Cynara cardunculus L., whose flowers are traditionally used in several Mediterranean countries in the manufacture of ewe's cheese. We have been characterizing cardosins at the biochemical, structural and molecular levels. In this study, we show that the cardoon aspartic proteases are encoded by a multigene family. The genes for cardosin A and cardosin B, as well as those for two new cardoon aspartic proteases, designated cardosin C and cardosin D, were characterized, and their expression in C. cardunculus L. was analyzed by RT-PCR. Together with cardosins, a partial clone of the cyprosin B gene was isolated, revealing that cardosin and cyprosin genes coexist in the genome of the same plant. As a first approach to understanding what dictates the flower-specific pattern of cardosin genes, the respective gene 5' regulatory sequences were fused with the reporter beta-glucuronidase and introduced into Arabidopsis thaliana. A subsequent deletion analysis of the promoter region of the cardosin A gene allowed the identification of a region of approximately 500 bp essential for gene expression in transgenic flowers. Additionally, the relevance of the leader intron of the cardosin A and B genes for gene expression was evaluated. Our data showed that the leader intron is essential for cardosin B gene expression in A. thaliana. In silico analysis revealed the presence of potential regulatory motifs that lay within the aforementioned regions and therefore might be important in the regulation of cardosin expression. 相似文献
102.
Marreiro DN do Perpetuo Socorro C Martins M de Sousa SS Ibiapina V Torres S Pires LV do Nascimento Nogueira N Lima JM do Monte SJ 《Biological trace element research》2007,120(1-3):42-50
The objective of this study was to assess urinary excretion of zinc and evaluation parameters of metabolic control in type
2 diabetic patients. Thirty-one type 2 diabetic patients, of both genders, with 5.8 ± 5.6 years average time of the disease,
age range 20–60 years, were selected. Evaluation of the nutritional status was performed using anthropometric measurements.
To evaluate food consumption, the 3-day alimentary log method was used, and its analysis was performed using a software. Determination
of urinary zinc was by atomic absorption spectrophotometry. From the obtained results, it was concluded that 51.6% of the
patients were overweight. The mean of found waist circumference was 100.4 and 92.2 cm for men and women, respectively. Blood
glucose and glycated hemoglobin values were higher than reference values, and plasma albumin concentration was adequate. The
median of found urinary zinc excretion was 474.9 μg/24 h, within normal standards (300–600 μg/day). Regarding diet composition,
calorie and protein concentration were above recommendation, while mean zinc concentration was adequate. This data allow the
conclusion that the evaluated patients presented adequate urinary zinc excretion in comparison with reference values. 相似文献
103.
Payan-Carreira R Santana I Pires MA Holst BS Rodriguez-Martinez H 《Theriogenology》2012,77(8):1540-1548
Tumor necrosis factor (TNF), formerly known as Tumor necrosis factor alpha is now regarded as a natural component of the mammalian seminal plasma (SP). Although not completely clarified, its functions in the SP have been associated with paradoxal roles, such as sperm survival in the female genital tract, while at high levels negatively affect sperm survival and fertility potential. Recently, it has been discovered that canine inseminated spermatozoa display a strong immunoreaction for TNF when lining the female endometrium. As a continuation of this finding, the present work aimed at documenting TNF localization in the canine testes and epididymis and in freshly ejaculated spermatozoa (SPZ) through immunohisto- or cytochemistry.Immunoreaction for TNF was found in all samples used. In the dog testis, TNF immunoexpression was limited to the seminiferous tubules, where late round spermatids (SPD) showed weak intensity of immunostaining, while elongating and elongated SPD evidenced moderate and the residual bodies a strong intensity. In the epididymis, a gradual progressive increase of TNF immunolabelling was found throughout the epididymal regions, ranging from a weak intensity at the caput epididymis to a moderate intensity at the cauda. TNF immunolabelling was found in mature SPZ during the epididymal transit and also in freshly ejaculated SPZ, which showed a strong midpiece immunolabelling. Data presented here provide important information on expression of TNF in spermatozoa, which is acquired by the SPZ during their formation at the testis. It further provides the basis for subsequent studies on the physiological importance of cytokines in sperm function. 相似文献
104.
RG Collevatti TG de Castro J de Souza Lima MP de Campos Telles 《Ecology and evolution》2012,2(5):1024-1035
Many endemic species present disjunct geographical distribution; therefore, they are suitable models to test hypotheses about the ecological and evolutionary mechanisms involved in the origin of disjunct distributions in these habitats. We studied the genetic structure and phylogeography of Tibouchina papyrus (Melastomataceae), endemic to rocky savannas in Central Brazil, to test hypothesis of vicariance and dispersal in the origin of the disjunct geographical distribution. We sampled 474 individuals from the three localities where the species is reported: Serra dos Pirineus, Serra Dourada, and Serra de Natividade. Analyses were based on the polymorphisms at cpDNA and on nuclear microsatellite loci. To test for vicariance and dispersal we constructed a median-joining network and performed an analysis of molecular variance (AMOVA). We also tested population bottleneck and estimated demographic parameters and time to most recent common ancestor (TMRCA) using coalescent analyses. A remarkable differentiation among populations was found. No significant effect of population expansion was detected and coalescent analyses showed a negligible gene flow among populations and an ancient coalescence time for chloroplast genome. Our results support that the disjunct distribution of T. papyrus may represent a climatic relict. With an estimated TMRCA dated from ~836.491 ± 107.515 kyr BP (before present), we hypothesized that the disjunct distribution may be the outcome of bidirectional expansion of the geographical distribution favored by the drier and colder conditions that prevailed in much of Brazil during the Pre-Illinoian glaciation, followed by the retraction as the climate became warmer and moister. 相似文献
105.
WM Monteiro LK Magalhães AR de Sá ML Gomes MJ Toledo L Borges I Pires JA de Oliveira Guerra H Silveira Md Barbosa 《PloS one》2012,7(7):e41284
Background
Chagas disease is an emergent tropical disease in the Brazilian Amazon Region, with an increasing number of cases in recent decades. In this region, the sylvatic cycle of Trypanosoma cruzi transmission, which constitutes a reservoir of parasites that might be associated with specific molecular, epidemiological and clinical traits, has been little explored. The objective of this work is to genetically characterize stocks of T. cruzi from human cases, triatomines and reservoir mammals in the State of Amazonas, in the Western Brazilian Amazon.Methodology/Principal Findings
We analyzed 96 T. cruzi samples from four municipalities in distant locations of the State of Amazonas. Molecular characterization of isolated parasites from cultures in LIT medium or directly from vectors or whole human blood was performed by PCR of the non-transcribed spacer of the mini-exon and of the 24 S alfa ribosomal RNA gene, RFLP and sequencing of the mitochondrial cytochrome c oxidase subunit II (COII) gene, and by sequencing of the glucose-phosphate isomerase gene. The T. cruzi parasites from two outbreaks of acute disease were all typed as TcIV. One of the outbreaks was triggered by several haplotypes of the same DTU. TcIV also occurred in isolated cases and in Rhodnius robustus. Incongruence between mitochondrial and nuclear phylogenies is likely to be indicative of historical genetic exchange events resulting in mitochondrial introgression between TcIII and TcIV DTUs from Western Brazilian Amazon. TcI predominated among triatomines and was the unique DTU infecting marsupials.Conclusion/Significance
DTU TcIV, rarely associated with human Chagas disease in other areas of the Amazon basin, is the major strain responsible for the human infections in the Western Brazilian Amazon, occurring in outbreaks as single or mixed infections by different haplotypes. 相似文献106.
Oliveira AC Peres CM Correia Pires JM Silva Pereira C Vitorino S Figueiredo Marques JJ Barreto Crespo MT San Romão MV 《Microbiological research》2003,158(2):117-124
AIMS: The main aims of this work were the study of cork slabs moulds colonization and the evaluation of the moulds diversity during cork processing steps, in different cork stoppers factories. Simultaneously, it was envisaged to perform an evaluation of the air quality. METHODS AND RESULTS: Moulds were isolated and identified from cork slabs and cork samples in four cork stoppers factories. The identification was based on morphological characters and microscopic observation of the reproductive structures. Airborne spore dispersion was assessed using a two stage Andersen sampler. It was observed that Chrysonilia sitophila was always present on cork slabs during the maturing period, but mould diversity appeared to be associated to the different factory configurations and processing steps. CONCLUSIONS: Spatial separation of the different steps of the process, including physical separation of the maturation step, is essential to guarantee high air quality and appropriate cork slabs colonization, i.e. C. sitophila dominance. The sorting and cutting of the edges of cork slabs after boiling and before the maturing step is also recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is very important for the cork stopper industry as it gives clear indications on how to keep high quality manufacturing standards and how to avoid occupational health problems. 相似文献
107.
Soares TN Melo DB Resende LV Vianello RP Chaves LJ Collevatti RG Telles MP 《American journal of botany》2012,99(2):e72-e73
? Premise of the study: Microsatellite markers were developed for the population genetic analyses of the neotropical tree Dipteryx alata (Fabaceae). ? Methods and Results: Microsatellites were developed from a genomic shotgun library. Polymorphism at each microsatellite loci was analyzed based on 94 individuals from three populations. Eight loci amplified successfully and presented one to 10 alleles, and expected heterozygosities ranged from 0.097 to 0.862. Four loci also amplified in Pterodon emarginatus and presented similar polymorphism. ? Conclusion: The eight microsatellite primer pairs are potentially suitable for population genetic studies and successfully amplified in another Fabaceae species. 相似文献
108.
109.
CAROLINE BETTO‐COLLIARD MATTHIAS STÖCK 《Biological journal of the Linnean Society. Linnean Society of London》2012,105(3):584-590
In vertebrates, genome size has been shown to correlate with nuclear and cell sizes, and influences phenotypic features, such as brain complexity. In three different anuran families, advertisement calls of polyploids exhibit longer notes and intervals than diploids, and difference in cellular dimensions have been hypothesized to cause these modifications. We investigated this phenomenon in green toads (Bufo viridis subgroup) of three ploidy levels, in a different call type (release calls) that may evolve independently from advertisement calls, examining 1205 calls, from ten species, subspecies, and hybrid forms. Significant differences between pulse rates of six diploid and four polyploid (3n, 4n) green toad forms across a range of temperatures from 7 to 27 °C were found. Laboratory data supported differences in pulse rates of triploids vs. tetraploids, but failed to reach significance when including field recordings. This study supports the idea that genome size, irrespective of call type, phylogenetic context, and geographical background, might affect call properties in anurans and suggests a common principle governing this relationship. The nuclear‐cell size ratio, affected by genome size, seems the most plausible explanation. However, we cannot rule out hypotheses under which call‐influencing genes from an unexamined diploid ancestral species might also affect call properties in the hybrid‐origin polyploids. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 584–590. 相似文献
110.
Altered patterns of fractionation and exon deletions in Brassica rapa support a two-step model of paleohexaploidy 总被引:2,自引:0,他引:2
Tang H Woodhouse MR Cheng F Schnable JC Pedersen BS Conant G Wang X Freeling M Pires JC 《Genetics》2012,190(4):1563-1574
The genome sequence of the paleohexaploid Brassica rapa shows that fractionation is biased among the three subgenomes and that the least fractionated subgenome has approximately twice as many orthologs as its close (and relatively unduplicated) relative Arabidopsis than had either of the other two subgenomes. One evolutionary scenario is that the two subgenomes with heavy gene losses (I and II) were in the same nucleus for a longer period of time than the third subgenome (III) with the fewest gene losses. This "two-step" hypothesis is essentially the same as that proposed previously for the eudicot paleohexaploidy; however, the more recent nature of the B. rapa paleohexaploidy makes this model more testable. We found that subgenome II suffered recent small deletions within exons more frequently than subgenome I, as would be expected if the genes in subgenome I had already been near maximally fractionated before subgenome III was introduced. We observed that some sequences, before these deletions, were flanked by short direct repeats, a unique signature of intrachromosomal illegitimate recombination. We also found, through simulations, that short--single or two-gene--deletions appear to dominate the fractionation patterns in B. rapa. We conclude that the observed patterns of the triplicated regions in the Brassica genome are best explained by a two-step fractionation model. The triplication and subsequent mode of fractionation could influence the potential to generate morphological diversity--a hallmark of the Brassica genus. 相似文献