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991.
Jaquelline Carla Valamiel de Oliveira-Silva Girley Francisco Machado-de-Assis Maykon Tavares Oliveira Nívia Carolina Noguieira Paiva Márcio Sobreira Silva Araújo Cláudia Martins Carneiro Olindo Assis Martins-Filho Helen Rodrigues Martins Marta de Lana 《Memórias do Instituto Oswaldo Cruz》2015,110(1):86-94
Trypanosoma cruzi strains from distinct geographic areas show differences in drug
resistance and association between parasites genetic and treatment response has been
observed. Considering that benznidazole (BZ) can reduce the parasite burden and
tissues damage, even in not cured animals and individuals, the goal is to assess the
drug response to BZ of T. cruzi II strains isolated from children of the
Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected
and treated with BZ in both phases of infection were compared with the untreated and
evaluated by fresh blood examination, haemoculture, polymerase chain reaction,
conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated in
the acute phase, a significant decrease in parasitaemia was observed for all strains.
Positive parasitological and/or serological tests in animals treated during the acute
and chronic (95.1-100%) phases showed that most of the strains were BZ resistant.
However, beneficial effect was demonstrated because significant reduction (p <
0.05%) and/or suppression of parasitaemia was observed in mice infected with all
strains (acute phase), associated to reduction/elimination of inflammation and
fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals,
what suggest that BZ use may be recommended at least for recent chronic infection of
the studied region. 相似文献
992.
Alex Pauvolid-Corrêa Raquel Soares Juliano Zilca Campos Jason Velez Rita Maria Ribeiro Nogueira Nicholas Komar 《Memórias do Instituto Oswaldo Cruz》2015,110(1):125-133
The Pantanal hosts diverse wildlife species and therefore is a hotspot for arbovirus
studies in South America. A serosurvey for Mayaro virus (MAYV), eastern (EEEV),
western (WEEV) and Venezuelan (VEEV) equine encephalitis viruses was conducted with
237 sheep, 87 free-ranging caimans and 748 equids, including 37 collected from a
ranch where a neurologic disorder outbreak had been recently reported. Sera were
tested for specific viral antibodies using plaque-reduction neutralisation test. From
a total of 748 equids, of which 264 were immunised with vaccine composed of EEEV and
WEEV and 484 had no history of immunisation, 10 (1.3%) were seropositive for MAYV and
two (0.3%) for VEEV using criteria of a ≥ 4-fold antibody titre difference. Among the
484 equids without history of immunisation, 48 (9.9%) were seropositive for EEEV and
four (0.8%) for WEEV using the same criteria. Among the sheep, five were sero-
positive for equine encephalitis alphaviruses, with one (0.4%) for EEEV, one (0.4%)
for WEEV and three (1.3%) for VEEV. Regarding free-ranging caimans, one (1.1%) and
three (3.4%), respectively, had low titres for neutralising antibodies to VEEV and
undetermined alphaviruses. The neurological disorder outbreak could not be linked to
the alphaviruses tested. Our findings represent strong evidence that MAYV and all
equine encephalitis alphaviruses circulated in the Pantanal. 相似文献
993.
Louisy Sanches dos Santos Camila Azevedo Antunes Cintia Silva dos Santos José Augusto Adler Pereira Priscila Soares Sabbadini Maria das Gra?as de Luna Vasco Azevedo Raphael Hirata Júnior Andreas Burkovski Lídia Maria Buarque de Oliveira Asad Ana Luíza Mattos-Guaraldi 《Memórias do Instituto Oswaldo Cruz》2015,110(5):662-668
Corynebacterium diphtheriae, the aetiologic agent of diphtheria,
also represents a global medical challenge because of the existence of invasive
strains as causative agents of systemic infections. Although tellurite
(TeO32-) is toxic to most microorganisms, TeO32--resistant
bacteria, including C. diphtheriae, exist in
nature. The presence of TeO32--resistance (TeR)
determinants in pathogenic bacteria might provide selective advantages in the natural
environment. In the present study, we investigated the role of the putative
TeR determinant (CDCE8392_813gene) in the virulence
attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in
the LDCIC-L1 mutant increased susceptibility to TeO32- and reactive oxygen
species (hydrogen peroxide), but not to other antimicrobial agents. The LDCIC-L1
mutant also showed a decrease in both the lethality of Caenorhabditis elegans
and the survival inside of human epithelial cells compared to wild-type
strain. Conversely, the haemagglutinating activity and adherence to and formation of
biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813
gene. In conclusion, the CDCE8392_813 gene contributes to the TeR and
pathogenic potential of C. diphtheriae. 相似文献
994.
Karla?V.?Figueiredo Marciel?T.?Oliveira Emília?C.?P.?Arruda Bárbara?C.?F.?Silva Mauro?G.?SantosEmail author 《Acta Physiologiae Plantarum》2015,37(6):108
Jatropha curcas and Jatropha mollissima plants were evaluated under conditions of high (HSM) and low (LSM) soil moisture in a semi-arid environment, as changes in the content and concentration of epicuticular wax and the leaf metabolism which could have a relationship with drought tolerance. Besides epicuticular wax, gas exchange, antioxidant system and biochemical parameters of the photosynthetic metabolism were measured. The epicuticular wax content increased only in J. mollissima leaves 95 % under LSM, when compared with HSM conditions. Therefore, J. curcas invested less in the production of long-chain n-alkanes than did J. mollissima under LSM conditions. J. mollissima plants showed the highest CO2 assimilation rate during the HSM period compared to J. curcas. Both species showed high stability in some leaf biochemistry products, highlighting the highest sugar content, free amino acids, total soluble protein, and photosynthetic pigments in the leaves of J. mollissima plants under both of the soil moisture conditions. Moreover, the stability and performance of the different parameters, such as morphologic variables, seem to allow J. mollissima plants to tolerate semi-arid conditions. 相似文献
995.
996.
997.
Attila Balint TaeHyung Kim David Gallo Jose Renato Cussiol Francisco M Bastos de Oliveira Askar Yimit Jiongwen Ou Ryuichiro Nakato Alexey Gurevich Katsuhiko Shirahige Marcus B Smolka Zhaolei Zhang Grant W Brown 《The EMBO journal》2015,34(16):2182-2197
Obstructions to replication fork progression, referred to collectively as DNA replication stress, challenge genome stability. In Saccharomyces cerevisiae, cells lacking RTT107 or SLX4 show genome instability and sensitivity to DNA replication stress and are defective in the completion of DNA replication during recovery from replication stress. We demonstrate that Slx4 is recruited to chromatin behind stressed replication forks, in a region that is spatially distinct from that occupied by the replication machinery. Slx4 complex formation is nucleated by Mec1 phosphorylation of histone H2A, which is recognized by the constitutive Slx4 binding partner Rtt107. Slx4 is essential for recruiting the Mec1 activator Dpb11 behind stressed replication forks, and Slx4 complexes are important for full activity of Mec1. We propose that Slx4 complexes promote robust checkpoint signaling by Mec1 by stably recruiting Dpb11 within a discrete domain behind the replication fork, during DNA replication stress. 相似文献
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