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991.
Valdirene Neves Monteiro Roberto do Nascimento Silva Andrei Stecca Steindorff Fabio Teles Costa Eliane Ferreira Noronha Carlos André Ornelas Ricart Marcelo Valle de Sousa Marilene Henning Vainstein Cirano José Ulhoa 《Current microbiology》2010,61(4):298-305
Trichoderma harzianum ALL42 were capable of overgrowing and degrading Rhizoctonia solani and Macrophomina phaseolina mycelia, coiling around the hyphae with formation of apressoria and hook-like structures. Hyphae of T. harzianum ALL42 did not show any coiling around Fusarium sp. hyphae suggesting that mycoparasitism may be different among the plant pathogens. In this study, a secretome analysis
was used to identify some extracellular proteins secreted by T. harzianum ALL42 after growth on cell wall of M. phaseolina, Fusarium sp., and R. solani. The secreted proteins were analyzed by two-dimensional electrophoresis and MALDI-TOF mass spectrometry. A total of 60 T. harzianum ALL42 secreted proteins excised from the gel were analyzed from the three growth conditions. While seven cell wall-induced
proteins were identified, more than 53 proteins spots remain unidentified, indicating that these proteins are either novel
proteins or proteins that have not yet been sequenced. Endochitinase, β-glucosidase, α-mannosidase, acid phosphatase, α-1,3-glucanase,
and proteases were identified in the gel and also detected in the supernatant of culture. 相似文献
992.
Reduced neurotrophic support is one possible cause for retinal ganglion cells dying in glaucoma. Experiments were designed
to investigate the effect of EP2 receptor agonist butaprost on transformed retinal ganglion (RGC-5) cells where reduced neurotrophic
support was simulated by serum withdrawal. Cultures were analysed for cell viability, flow cytometry, reactive oxygen species
and apoptosis. Western blot and immunohistochemistry were used to provide information for the occurrence of PGE2 receptor-types. We demonstrated the existence of all four types of PGE2 receptors in RGC-5 cells and exposure of cultures to butaprost resulted in an elevation of cAMP. Serum deprivation induced
RGC-5 cell death was significantly attenuated by butaprost as well as by rolipram and forskolin where intracellular cAMP levels
were increased. These data are of value in relation to the possible use of EP2 receptor agonists to reduce both elevated intraocular
pressure and retinal ganglion cell death as occurs in glaucoma. 相似文献
993.
Maria Helena Ferreira de Azevedo Tarcízio Antônio Rego de Paula Sérgio Luis Pinto da Matta Cláudio César Fonseca Eduardo Paulino da Costa Deiler Sampaio Costa Juliano Vogas Peixoto 《Animal reproduction science》2010
The intrinsic yield of spermatogenesis and supporting capacity of Sertoli cells are the desirable indicators of sperm production in a species. The objective of the present study was to quantify intrinsic yield and the Sertoli cell index in the spermatogenic process and estimate testicular sperm reserves by histological assessment of fragments obtained by testicular biopsy of five adult jaguars in captivity. The testicular fragments were fixed in 4% glutaric aldehyde, dehydrated at increasing alcohol concentrations, included into hydroxyethyl methacrylate, and were cut into 4 μm thickness. In the seminiferous epithelium of the jaguar, 9.2 primary spermatocytes in pre-leptotene were produced by “A” spermatogonia. During the meiotic divisions only 3.2 spermatids were produced by a primary spermatocyte. The general spermatogenic yield of the jaguar was about 23.4 cells and each Sertoli cell was able to maintain about 19.2 germ cells, 11 of them were round spermatids. In each seminiferous epithelium cycle about 166 million spermatozoa were produced by each gram of testicular tissue. In adult jaguars, the general spermatogenic yield was similar to the yield observed in pumas, greater than that observed for the domestic cat, but less compared to most domestic animals. 相似文献
994.
Sébastien Moreau Gustavo A. Ferreyra Bernard Mercier Karine Lemarchand Marie Lionard Suzanne Roy Behzad Mostajir Sébastien Roy Bon van Hardenberg Serge Demers 《Polar Biology》2010,33(12):1599-1614
Although winter conditions play a major role in determining the productivity of the western Antarctic Peninsula (WAP) waters for the following spring and summer, a few studies have dealt with the seasonal variability of microorganisms in the WAP in winter. Moreover, because of regional warming, sea-ice retreat is happening earlier in spring, at the onset of the production season. In this context, this study describes the dynamics of the marine microbial community in the Melchior Archipelago (WAP) from fall to spring 2006. Samples were collected monthly to biweekly at four depths from the surface to the aphotic layer. The abundance and carbon content of bacteria, phytoplankton and microzooplankton were analyzed using flow cytometry and inverted microscopy, and bacterial richness was examined by PCR–DGGE. As expected, due to the extreme environmental conditions, the microbial community abundance and biomass were low in fall and winter. Bacterial abundance ranged from 1.2 to 2.8 × 105 cells ml?1 showing a slight increase in spring. Phytoplankton biomass was low and dominated by small cells (<2 μm) in fall and winter (average chlorophyll a concentration, Chl-a, of, respectively, 0.3 and 0.13 μg l?1). Phytoplankton biomass increased in spring (Chl-a up to 1.13 μg l?1), and, despite potentially adequate growth conditions, this rise was small and phytoplankton was still dominated by small cells (2–20 μm). In addition, the early disappearing of sea-ice in spring 2006 let the surface water exposed to ultraviolet B radiations (UVBR, 280–320 nm), which seemed to have a negative impact on the microbial community in surface waters. 相似文献
995.
Luciana Albuquerque Fred A. Rainey M. Fernanda Nobre Milton S. da Costa 《Systematic and applied microbiology》2010
Two red-pigmented isolates, with optimum growth temperatures between 45 and 50 °C, were recovered from a hot spring in the Furnas, Área da Fonte 1825 on the Island of São Miguel in the Azores. Phylogenetic analysis of the 16S rRNA gene sequences showed that these organisms represented a new species of the genus Meiothermus. These new isolates could be distinguished from other strains of the species of the genus Meiothermus primarily by the fatty acid composition and polar lipid pattern, since they did not possess 2-OH fatty acids or glycolipid variant GL-1a. Moreover, the two new isolates had the lowest growth temperature range of any of the known species of the genus Meiothermus. On the basis of the results presented here we propose the name Meiothermus granaticius for the new species represented by strains AF-68T (=DSM 23260T = LMG 25524T) and AF-49 (=DSM 23259 = LMG 25525). 相似文献
996.
Rita Negrão Raquel Costa Delfim Duarte Tiago Taveira Gomes Mário Mendanha Liane Moura Luísa Vasques Isabel Azevedo Raquel Soares 《Journal of cellular biochemistry》2010,111(5):1270-1279
Emerging evidence indicates that chronic inflammation and oxidative stress cluster together with angiogenic imbalance in a wide range of pathologies. In general, natural polyphenols present health‐protective properties, which are likely attributed to their effect on oxidative stress and inflammation. Hops used in beer production are a source of polyphenols such as xanthohumol (XN), and its metabolites isoxanthohumol (IXN) and phytoestrogen 8‐prenylnaringenin (8PN). Our study aimed to evaluate XN, IXN, and 8PN effects on angiogenesis and inflammation processes. Opposite in vitro effects were observed between 8PN, stimulating endothelial and smooth muscle cell (SMC) growth, motility, invasion and capillary‐like structures formation, and XN and IXN, which inhibited them. Mouse matrigel plug and rat skin wound‐healing assays confirmed that XN and IXN treatments reduced vessel number as well as serum macrophage enzymatic activity, whereas 8PN increased blood vessels formation in both assays and enzyme activity in the wound‐healing assay. A similar profile was found for serum inflammatory interleukin‐1β quantification, in the wound‐healing assay. Our data indicate that whereas 8PN stimulates angiogenesis, XN and IXN manifested anti‐angiogenic and anti‐inflammatory effects in identical conditions. These findings suggest that the effects observed for individual compounds on vascular wall cells must be carefully taken into account, as these polyphenols are metabolized after in vivo administration. The modulation of SMC proliferation and migration is also of special relevance, given the role of these cells in many pathological conditions. Furthermore, these results may provide clues for developing useful therapeutic agents against inflammation‐ and angiogenesis‐associated pathologies. J. Cell. Biochem. 111: 1270–1279, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
997.
Gianfabio Giorgioni Dario Ambrosini Cristian Vesprini Alan Hudson Cinzia Nasuti Antonio Di Stefano Piera Sozio Osele Ciampi Barbara Costa Claudia Martini Antonio Carrieri Giuseppe Carbonara Christoph Enzensperger Maria Pigini 《Bioorganic & medicinal chemistry》2010,18(19):7085-7091
Based on the well known biological versatility of the imidazoline nucleus, we prepared the novel derivatives 3a–k inspired by 2-BFI scaffold to assess imidazoline molecules as D2-like dopamine receptor ligands. Conservative chemical modifications of the lead structure, such as the introduction of an hydroxy group in the aromatic ring alone or associated with N-benzyl substitution, provided partial (3f) or nearly full (3e and 3h) agonists, all endowed with D2-like potency comparable to that of dopamine. 相似文献
998.
Galaxias maculatus (small puyen) is an abundant native fish distributed in lakes and rivers of the Patagonia, and it is the frequent prey of other fishes, fish-eating birds, and mammals. Previous studies have shown that it is parasitized by 33 metazoan species and that the richness and composition of the parasite communities vary between lakes. The aim of the present work was to analyze the relationship between the composition of fish assemblages and the helminth component community structure of G. maculatus . Ten environmentally similar, small, shallow lakes, belonging to the Nahuel Huapi Lake basin, were chosen because of the differences in the native fish assemblages. Parasite community structure in G. maculatus varied according to the fish assemblage of each lake. The presence of the piscivorous fish Percichthys trucha regularly produced variations in the composition and richness at the component and infracommunity levels, as well as the percentage of autogenic parasite species in G. maculatus . 相似文献
999.
Gonzalo E. Yevenes Gustavo Moraga-Cid Ariel Avila Leonardo Guzmán Maximiliano Figueroa Robert W. Peoples Luis G. Aguayo 《The Journal of biological chemistry》2010,285(39):30203-30213
It is now believed that the allosteric modulation produced by ethanol in glycine receptors (GlyRs) depends on alcohol binding to discrete sites within the protein structure. Thus, the differential ethanol sensitivity of diverse GlyR isoforms and mutants was explained by the presence of specific residues in putative alcohol pockets. Here, we demonstrate that ethanol sensitivity in two ligand-gated ion receptor members, the GlyR adult α1 and embryonic α2 subunits, can be modified through selective mutations that rescued or impaired Gβγ modulation. Even though both isoforms were able to physically interact with Gβγ, only the α1 GlyR was functionally modulated by Gβγ and pharmacological ethanol concentrations. Remarkably, the simultaneous switching of two transmembrane and a single extracellular residue in α2 GlyRs was enough to generate GlyRs modulated by Gβγ and low ethanol concentrations. Interestingly, although we found that these TM residues were different to those in the alcohol binding site, the extracellular residue was recently implicated in conformational changes important to generate a pre-open-activated state that precedes ion channel gating. Thus, these results support the idea that the differential ethanol sensitivity of these two GlyR isoforms rests on conformational changes in transmembrane and extracellular residues within the ion channel structure rather than in differences in alcohol binding pockets. Our results describe the molecular basis for the differential ethanol sensitivity of two ligand-gated ion receptor members based on selective Gβγ modulation and provide a new mechanistic framework for allosteric modulations of abuse drugs. 相似文献
1000.
Leonardo Faoro Patrick A. Singleton Gustavo M. Cervantes Frances E. Lennon Nicholas W. Choong Rajani Kanteti Benjamin D. Ferguson Aliya N. Husain Maria S. Tretiakova Nithya Ramnath Everett E. Vokes Ravi Salgia 《The Journal of biological chemistry》2010,285(24):18575-18585
Non-small cell lung cancer (NSCLC) has a poor prognosis and improved therapies are needed. Expression of EphA2 is increased in NSCLC metastases. In this study, we investigated EphA2 mutations in NSCLC and examined molecular pathways involved in NSCLC. Tumor and cell line DNA was sequenced. One EphA2 mutation was modeled by expression in BEAS2B cells, and functional and biochemical studies were conducted. A G391R mutation was detected in H2170 and 2/28 squamous cell carcinoma patient samples. EphA2 G391R caused constitutive activation of EphA2 with increased phosphorylation of Src, cortactin, and p130Cas. Wild-type (WT) and G391R cells had 20 and 40% increased invasiveness; this was attenuated with knockdown of Src, cortactin, or p130Cas. WT and G391R cells demonstrated a 70% increase in focal adhesion area. Mammalian target of rapamycin (mTOR) phosphorylation was increased in G391R cells with increased survival (55%) compared with WT (30%) and had increased sensitivity to rapamycin. A recurrent EphA2 mutation is present in lung squamous cell carcinoma and increases tumor invasion and survival through activation of focal adhesions and actin cytoskeletal regulatory proteins as well as mTOR. Further study of EphA2 as a therapeutic target is warranted. 相似文献