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141.
B. B. Fonseca I. L. Santos D. A. Rossi R. T. Melo T. G. Araújo C. U. Vieira E. P. Mendonça M. E. Beletti 《Indian journal of microbiology》2013,53(2):155-162
This study aimed to evaluate the participation of actin and tubulin in the process of internalisation, the interaction of bacterial phagosomes with lysosomes, the morphometric changes and the expression of inflammatory cytokines in Caco-2 cells infected with Campylobacter jejuni. Both actin and tubulin participated in the process of internalisation. Inside the cells, lysosomes fuse with phagosomes, which may lead to bacterial death because after 2 h, the bacteria were not detected by Transmission electron microscopy (TEM). There is increased expression of TGF-β3 during the early stages, and IL-8 was expressed after 60 min p.i. This work showed that C. jejuni invades and causes major morphometric changes in epithelial cells. In response, the cells increase their expression of cytokines that can lead to inflammation. The mechanisms of invasion are dependent on actin and tubulin, and once internalised, lysosomes fuse with phagosomes. 相似文献
142.
Marina Azevêdo Souza Susana Johann Luciana Alves Rodrigues dos Santos Lima Fernanda Fraga Campos Isolda Castro Mendes Heloisa Beraldo Elaine Maria de Souza-Fagundes Patrícia Silva Cisalpino Carlos Augusto Rosa Tania Maria de Almeida Alves Nívea Pereira de Sá Carlos Leomar Zani 《Memórias do Instituto Oswaldo Cruz》2013,108(3):342-351
Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone and semicarbazone derivatives were also active against the pathogenic yeast Cryptococcus gattii (MICs of 0.10 and 0.20 µmol/mL, respectively). In addition, the lapachol thiosemicarbazone derivative was active against 11 clinical isolates of Paracoccidioides brasiliensis, with MICs ranging from 0.01-0.10 µmol/mL. The lapachol-derived thiosemicarbazone was not cytotoxic to normal cells at the concentrations that were active against fungi and bacteria. We synthesised, for the first time, thiosemicarbazone and semicarbazone derivatives of lapachol. The MICs for the lapachol-derived thiosemicarbazone against S. aureus, E. faecalis, C. gattii and several isolates of P. brasiliensis indicated that this compound has the potential to be developed into novel drugs to treat infections caused these microbes. 相似文献
143.
144.
E. Rodriguez R. Azevedo C. Remédios T. Almeida P. Fernandes C. Santos 《Journal of plant physiology》2013
Chromium (Cr), as a mutagenic agent in plants, has received less attention than other metal pollutants. To understand if Cr induces microsatellite instability (MSI), Pisum sativum seedlings were exposed for 28 days to different concentrations of Cr(VI) up to 2000 mg L−1, and the genetic instability of ten microsatellites (SSRs) was analyzed. In plants exposed to Cr(VI) up to 1000 mg L−1, MSI was never observed. However, roots exposed to 2000 mg L−1 displayed MSI in two of the loci analyzed, corresponding to a mutation rate of 8.3%. SSR2 (inserted in the locus for plastid photosystem I 24 kDa light harvesting protein) and SSR6 (inserted in the locus for P. sativum glutamine synthetase) from Cr(VI)-treated roots presented alleles with, respectively, less 6 bp and more 3 bp than the corresponding controls. This report demonstrates that: (a) SSRs technique is sensitive to detect Cr-induced mutagenicity in plants, being Cr-induced-MSI dose and organ dependent (roots are more sensitive); (b) two Cr-sensitive loci are related with thylakoid photophosphorylation and with glutamine synthetase, respectively; (c) despite MSI is induced by Cr(VI), it only occurs in plants exposed to concentrations higher than 1000 mg L−1 (values rarely found in real scenarios). Considering these data, we also discuss the known functional changes induced by Cr(VI) in photosynthesis and in glutamine synthetase activity. 相似文献
145.
M. T. Kütter J. M. Monserrat R. A. Santos M. B. Tesser 《Zeitschrift fur angewandte Ichthyologie》2013,29(5):1123-1128
This study evaluated the effect of different doses of the antioxidant α‐lipoic acid (LA) administered by intraperitoneal injection on the detoxifying capacity (activity of glutathione‐S‐transferase, GST) and oxidative damage (lipids and proteins) in the pompano, Trachinotus marginatus. The plasma glucose levels showed that there were no differences between the treatments (P > 0.05). In the brain, GST activity was significantly higher (P < 0.05) in fish injected with 40 mg LA kg?1 when compared with the control group. In the muscle, GST activity was not influenced by LA treatment (P > 0.05). In the liver, fish injected with 20 mg LA kg?1 showed higher GST activity than the control group (P < 0.05); however, higher doses (40 and 60 mg LA kg?1) led to a reduction of GST activity in the liver, which was comparable to that observed in the control group (P > 0.05). The two highest LA doses (40 and 60 mg kg?1) had opposite effects, depending on the tissue examined: LA was an antioxidant in the brain, reducing lipid peroxidation (P < 0.05), and a pro‐oxidant in the liver, augmenting oxidative lipid damage (P < 0.05). The latter effect was accompanied by an increase in the free iron concentration in the liver at higher LA doses. These results indicate the need to thoroughly evaluate the antioxidant effects on aquatic organisms, since at some doses and/or in some organs their beneficial effects can be lost. 相似文献
146.
Miguel dos Santos Daniel J. Rankin Claus Wedekind 《Evolution; international journal of organic evolution》2013,67(8):2446-2450
The threat of punishment usually promotes cooperation. However, punishing itself is costly, rare in nonhuman animals, and humans who punish often finish with low payoffs in economic experiments. The evolution of punishment has therefore been unclear. Recent theoretical developments suggest that punishment has evolved in the context of reputation games. We tested this idea in a simple helping game with observers and with punishment and punishment reputation (experimentally controlling for other possible reputational effects). We show that punishers fully compensate their costs as they receive help more often. The more likely defection is punished within a group, the higher the level of within‐group cooperation. These beneficial effects perish if the punishment reputation is removed. We conclude that reputation is key to the evolution of punishment. 相似文献
147.
S. S. Araújo A. S. Duque J. M. Silva D. Santos A. B. Silva P. Fevereiro 《Biologia Plantarum》2013,57(1):159-163
In this article, we present the response of Medicago truncatula Gaert. cv. Jemalong plants expressing constitutively the Dsp22 gene from Craterostigma plantagineum to water stress and rehydration. The Dsp22 gene encodes an ELIP-like protein thought to protect the chloroplast against photooxidative damage during the dehydration and rehydration. The Dsp22 transgenic homozygous M. truncatula plants showed higher amount of chlorophyll (Chl), lower Chl a/Chl b ratio and higher actual efficiency of energy conversion in photosystem 2 (ΦPSII) after rehydration, when compared to the wild type. The combined data from the Chl a fluorescence analysis, pigment quantification and biomass accumulation showed that transgenic M. truncatula plants are able to recover from water deprivation better than wild type plants. 相似文献
148.
Sunglim Cho Miriam Lee Youngsoo Jun 《Biochemical and biophysical research communications》2013,430(2):787-792
Aberrantly folded proteins in the endoplasmic reticulum (ER) are rapidly removed into the cytosol for degradation by the proteasome via an evolutionarily conserved process termed ER-associated protein degradation (ERAD). ERAD of a subset of proteins requires Derlin-1 for dislocation into the cytosol; however, the molecular function of Derlin-1 remains unclear. Human cytomegalovirus US11 exploits Derlin-1-dependent ERAD to degrade major histocompatibility complex class I (MHC-I) molecules for immune evasion. Because US11 binds to both MHC-I molecules and Derlin-1 via its luminal and transmembrane domains (TMDs), respectively, the major role of US11 has been proposed to simply be delivery of MHC-I molecules to Derlin-1. Here, we directly tested this proposal by generating a hybrid MHC-I molecule, which contains the US11 TMD, and thus can associate with Derlin-1 in the absence of US11. Intriguingly, this MHC-I hybrid was rapidly degraded in a Derlin-1- and proteasome-dependent manner. Similarly, the vesicular stomatitis virus G protein, otherwise expressed at the cell surface, was degraded via Derlin-1-dependent ERAD when its TMD was replaced with that of US11. Thus, forced interaction of cell surface proteins with Derlin-1 is sufficient to induce their degradation via ERAD. Taken together, these results suggest that the main role of US11 is to recruit MHC-I molecules to Derlin-1, which then mediates the dislocation of MHC-I molecules into the cytosol for degradation. 相似文献
149.
Rodolpho Santos Telles Menezes Thiago Magalhães Silva Antônio Freire Carvalho Vanderly Andrade-Souza Janisete Gomes Silva Marco Antonio Costa 《Genetica》2013,141(7-9):273-280
The Neotropical Polistinae wasps are diverse in taxonomy, social behavior, and nesting founding characteristics. Although some species in this group have been used as models for studies on wasp’s biology, they are poorly known in terms of cytogenetics. Here we reported an intraspecific numerical-structural chromosome variation in the swarm-founding wasp Metapolybia decorata from the Brazilian Atlantic Rainforest using conventional and molecular cytogenetic techniques. The observed structural chromosome change involved a telomeric fusion that resulted in a chromosome number range of 2n = 34–36. The origin and geographic distribution of the variant chromosome forms as well as their frequency and maintenance in the studied populations are discussed. In addition, we reported a novel and geographically restricted deletion in the fused chromosomes indicating that the species is undergoing a continued process of karyotype evolution leading to fused chromosome stabilization by elimination of inactive centromeric sequences. Evidence of differences in the telomeric sequences of this wasp was also found by in situ hybridization using the motif (T2AG2)7 as probe. 相似文献
150.
Miriam Andrés Mónica Bravo Maria Antonia Buil Marta Calbet Jordi Castro Teresa Domènech Peter Eichhorn Manel Ferrer Elena Gómez Martin D. Lehner Imma Moreno Richard S. Roberts Sara Sevilla 《Bioorganic & medicinal chemistry letters》2013,23(11):3349-3353
High throughput screening identified the pyrazole-4-acetic acid substructure as CRTh2 receptor antagonists. Optimisation of the compounds uncovered a tight SAR but also identified some low nanomolar inhibitors. 相似文献