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141.
Renan Cardoso Soares Marcelo Bergamin Zani Ana Carolina Belini Bazán Arruda Lucia Helena Fávaro de Arruda Luciana Campos Paulino 《PloS one》2015,10(2)
Malassezia yeasts are part of the resident cutaneous microbiota, and are also associated with skin diseases such as seborrheic dermatitis (SD). The role these fungi play in skin diseases and why they are pathogenic for only some individuals remain unclear. This study aimed to characterize Malassezia microbiota from different body sites in healthy and SD subjects from Brazil. Scalp and forehead samples from healthy, mild SD and severe SD subjects were collected. Non-scalp lesions from severe SD patients were also sampled. 5.8S rDNA/ITS2 amplicons from Malassezia sp. were analyzed by RFLP and sequencing. Results indicate that Malassezia microbiota did not group according to health condition or body area. Phylogenetic analysis revealed that three groups of sequences did not cluster together with any formally described species, suggesting that they might belong to potential new species. One of them was found in high proportions in scalp samples. A large variety of Malassezia subtypes were detected, indicating intra-specific diversity. Higher M. globosa proportions were found in non-scalp lesions from severe SD subjects compared with other areas, suggesting closer association of this species with SD lesions from areas other than scalp. Our results show the first panorama of Malassezia microbiota in Brazilian subjects using molecular techniques and provide new perspectives for further studies to elucidate the association between Malassezia microbiota and skin diseases. 相似文献
142.
Experiments were performed to investigate senses that are essential for mediating fright reaction and food behavior in Pseudoplatystoma corruscans, pintado. The dilemma “to feed or to flee” was also analyzed in fishes with intact and sectioned olfactory tracts, stimulated
by alarm substance extracts and food. Fishes were arranged into five groups: fish with intact lateral olfactory tracts (LOT),
fish with intact medial olfactory tract (MOT), fish with tracts totally sectioned (TOTAL, both LOT and MOT), sham operated,
and nonoperated fish. The five groups were submitted to either alarm substance extract and food stimulus or to distilled water
(control) and food stimulus. Fish reacted to food independently of which tract (LOT, MOT or TOTAL) was sectioned; vision seems
necessary and elemental to detect and deflagrate food response. Latency of the responses to each reaction was different between
groups. None of the fish with sectioned tracts reacted to alarm substance extract, while sham- and nonoperated fish showed
the typical alarm behavior response, leading to the conclusion that olfaction is essential for mediating alarm response. These
results indicate that others sense systems (e.g., vision) are sufficient to trigger and elicit feeding behavior and that olfaction
is not necessary to fully maintain food detection to qualitative and quantitative extent. However, olfactory tract integrity
seems to be required for mediation of alarm reaction in P. corruscans. 相似文献
143.
Simone V. Generoso Mirelle Viana Rosana Santos Flaviano S. Martins José A. N. Machado Rosa M. E. Arantes Jacques R. Nicoli Maria I. T. D. Correia Valbert N. Cardoso 《Archives of microbiology》2010,192(6):477-484
Probiotic is a preparation containing microorganisms that confers beneficial effect to the host. This work assessed whether
oral treatment with viable or heat-killed yeast Saccharomyces cerevisiae strain UFMG 905 prevents bacterial translocation (BT), intestinal barrier integrity, and stimulates the immunity, in a murine
intestinal obstruction (IO) model. Four groups of mice were used: mice undergoing only laparotomy (CTL), undergoing intestinal
obstruction (IO) and undergoing intestinal obstruction after previous treatment with viable or heat-killed yeast. BT, determined
as uptake of 99mTc-E. coli in blood, mesenteric lymph nodes, liver, spleen and lungs, was significantly higher in IO group than in CTL group. Treatments
with both yeasts reduced BT in blood and all organs investigated. The treatment with both yeasts also reduced intestinal permeability
as determined by blood uptake of 99mTc-DTPA. Immunological data demonstrated that both treatments were able to significantly increase IL-10 levels, but only viable
yeast had the same effect on sIgA levels. Intestinal lesions were more severe in IO group when compared to CTL and yeasts
groups. Concluding, both viable and heat-killed cells of yeast prevent BT, probably by immunomodulation and by maintaining
gut barrier integrity. Only the stimulation of IgA production seems to depend on the yeast viability. 相似文献
144.
Hélia Guerra Cardoso Maria Catarina Campos Maria Salomé Pais Augusto Peixe 《In vitro cellular & developmental biology. Plant》2010,46(6):499-508
Somatic embryogenesis induction from in vitro cultured stamens and carpels is highly dependent on explants’ inoculation at specific developmental stages. To establish
good correlations between measurable morphometric parameters of flowers or flower buds and developmental stages of micro-
and macrosporogenesis, this procedure is the easiest way to simplify the in vitro culture procedures. These correlations were established here for the most important Iberian grapevine cultivar, the “Aragonez”,
named “Tempranillo” in Spain and “Tinta Roriz” in the north of Portugal, and were based in floral buds and anther measurements.
The anther length, with a correlation coefficient of 0.90, proved to be the best morphometric parameter to follow microsporogenesis
evolution. A correlation between micro- and macrosporogenesis evolutionary stages was also positively established, allowing
the use of morphometric parameters for tracking ovule evolution as well. Carpels in several evolutionary stages were in vitro cultured to evaluate the aging effect on the capacity for somatic embryogenesis induction. Explants inoculated in the earliest
stages of macrosporogenesis presented the best results. Media culture formulations were also tested for ovary culture, with
the best results being achieved with a 5:1 auxin/cytokinin ratio. 相似文献
145.
146.
Stolf-Moreira R Medri ME Neumaier N Lemos NG Pimenta JA Tobita S Brogin RL Marcelino-Guimarães FC Oliveira MC Farias JR Abdelnoor RV Nepomuceno AL 《Genetics and molecular research : GMR》2010,9(4):1946-1956
Soybean genotypes MG/BR46 (Conquista) and BR16, drought-tolerant and -sensitive, respectively, were compared in terms of morphophysiological and gene-expression responses to water stress during two stages of development. Gene-expression analysis showed differential responses in Gmdreb1a and Gmpip1b mRNA expression within 30 days of water-deficit initiation in MG/BR46 (Conquista) plants. Within 45 days of initiating stress, Gmp5cs and Gmpip1b had relatively higher expression. Initially, BR16 showed increased expression only for Gmdreb1a, and later (45 days) for Gmp5cs, Gmdefensin and Gmpip1b. Only BR16 presented down-regulated expression of genes, such as Gmp5cs and Gmpip1b, 30 days after the onset of moisture stress, and Gmgols after 45 days of stress. The faster perception of water stress in MG/BR46 (Conquista) and the better maintenance of up-regulated gene expression than in the sensitive BR16 genotype imply mechanisms by which the former is better adapted to tolerate moisture deficiency. 相似文献
147.
148.
Aderaldo I.L. Araujo Adriana M. de Almeida Márcio Z. Cardoso Gilberto Corso 《Ecological Complexity》2010,7(4):494-499
Nestedness is a useful metric that characterizes the generalist–specialist balance in ecological communities. Although several nestedness indices have been proposed, few have explored how species abundance per se affects their performance and the ability to detect true interaction networks. We here develop a mathematical framework that takes into account abundance in estimates of nestedness. We use an analytical approach to relate abundance and nestedness. In our null model the probability of interaction among species is determined solely as function of their abundances. Assuming a power-law abundance model we analytically find the nestedness index and its coefficient of variability. We find that the sloping abundance distribution of our null model generates more nested structures. On the other hand steeper abundances lead to higher coefficients of variability. Both results suggest that nestedness analysis should be evaluated and explanations sought carefully. 相似文献
149.
Claudia NCD Lemos Fernando M Reis Guilherme N Pena Laila C Silveira Aroldo F Camargos 《Reproductive biology and endocrinology : RB&E》2010,8(1):51
Background
Reproductive function following chemotherapy is of increasing importance given that survival rates are improving. We assessed whether a gonadotropin-releasing hormone antagonist (GnRHant; cetrorelix) could promote ovarian protection against damage due to chemotherapy. 相似文献150.
André M. Almeida Enrique Villalobos Susana S. Araújo Luis A. Cardoso Dulce M. Santos Maria A. Santos Pedro S. Fevereiro José M. Torné 《Acta Physiologiae Plantarum》2007,29(3):273-281
Trehalose is a non-reducing disaccharide of glucose that occurs in a large number of organisms, playing an important role
in desiccation and heat stress protection. Trehalose accumulation has proven to be an effective way of increasing drought
tolerance in both model plants such as tobacco and important crops such as potato or rice. In this work we aim to genetically
engineer maize with the Arabidopsis thaliana trehalose phosphate synthase gene (AtTPS1), involved in trehalose biosynthesis via electroporation. A cassette harboring the
AtTPS1 gene under the control of the CaMV35S promoter and the Bialaphos resistance gene Bar as a selective agent was inserted
in the plasmid vector pGreen0229 and used to transform maize inbred line Pa91 via electroporation. Fifteen putative transgenic
plants (T0 generation) were obtained. Transgene integration in T0 plants was analyzed by Southern-blot analysis. T0 plants
had normal phenotypes, although smaller than wild type plants. Contrary to wild type plants, when sexual organs emerged, tassels
appeared at least 15 days earlier than ears in the same plant, rendering impossible the self-pollination of the T0 plant.
These plants were then crossed with wild type plants and in some cases T1 seeds were obtained. T1 seeds presented deformities,
especially the lack of endosperm, but it was still possible to germinate some of these seeds. The so obtained plants were
tested by Northern blot but no AtTPS1 gene expression was detected, a fact possibly due to the incomplete insertion of the
AtTPS1 gene or an extremely low gene expression level. 相似文献