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991.
Deyze Alencar Soares Marilia Barros Oliveira Adriane Feijó Evangelista Emerson José Venancio Rosangela Vieira Andrade Maria Sueli Soares Felipe Silvana Petrofeza 《Memórias do Instituto Oswaldo Cruz》2013,108(6):808-811
Phospholipase is an important virulence factor for pathogenic fungi. In this
study, we demonstrate the following: (i) the Paracoccidioides
brasiliensis pld gene is preferentially expressed in mycelium
cells, (ii) the plb1 gene is mostly up-regulated by infection
after 6 h of co-infection of MH-S cells or during BALB/c mice
lung infection, (iii) during lung infection, plb1,
plc and pld gene expression are
significantly increased 6-48 h post-infection compared to 56 days after
infection, strongly suggesting that phospholipases play a role in the early
events of infection, but not during the chronic stages of pulmonary infection by
P. brasiliensis. 相似文献
992.
Tatiane Campos Trigo Flávia Pereira Tirelli Leonardo Ferreira Machado Felipe Bortolotto Peters Cibele Barros Indrusiak Fábio Dias Mazim 《Studies on Neotropical Fauna and Environment》2013,48(1):56-67
The objective of this study is to define the geographic distribution of Leopardus tigrinus and L. geoffroyi in one of the few regions of South America where they co-occur, the state of Rio Grande do Sul (RS), in southernmost Brazil. We compiled 133 records for both species and constructed a distribution map, which shows sharp geographic segregation between them. Leopardus tigrinus was found to be associated more with forested ecoregions in the northern part of the state, while L. geoffroyi records were mainly associated with open habitats of the Pampas biome in southern RS. We present data on the diet of these two species that indicate trophic niche separation between them in this region of geographic contact. Our results thus suggest that these species exhibit ecological partitioning with respect to habitat and prey, and that these factors may influence the observed pattern of limited spatial overlap in this region. 相似文献
993.
Marcelo Aguiar Costa-Lima Márcia Rodrigues Amorim Iêda Maria Orioli 《Molecular biology reports》2013,40(3):2115-2125
The association between Down syndrome (DS) and maternal polymorphisms in genes encoding folic acid metabolizing enzymes remains a controversial issue. A meta-analysis was performed to evaluate the association of maternal MTHFR 677C > T polymorphism and the risk of having a child with DS. Case–control studies were screened from major literature databases. Twenty articles from 13 countries worldwide, with a total of 2,101 DS and 2,702 control mothers, attended the inclusion criteria. We found a 50 % increase for the association of maternal homozygous TT genotype and DS in both fixed (OR = 1.51; 95 % CI 1.22–1.87) and random effects models (OR 1.54; 95 % 1.15–2.05). Similarly, a significant pooled OR was found for the heterozygote CT, with an OR 1.26; 95 % CI 1.10–1.43 (fixed effects model) and OR 1.28; 95 % 1.08–1.51 (random effects model). As ultra-violet B solar radiation highly depends on latitude, and can promote, in less pigmented skin, intravascular folate photolysis, we stratified the analysis by latitude region, defining as Tropical (between 23.5° S and 23.5° N), Sub-Tropical (between 23.5° and 40° N and S), and Northern (≥40o N). Significant association was only found for Sub-Tropical area, both using fixed and random effect models. In conclusion, MTHFR 677C > T polymorphism is a moderate risk factor for DS for some populations, and populations located in Sub-Tropical region seem to be at greater risk. Latitude, ethnicity, skin pigmentation, and red blood cell folate are important variables to be considered in future studies. 相似文献
994.
Patrícia Amorim da Cunha Lia Kubelka de Carlos Back Aline Fernanda Rodrigues Sereia Clara Kubelka Maria Cecíia Menks Ribeiro Bráulio Leal Fernandes Ilíada Rainha de Souza 《Molecular biology reports》2013,40(12):6657-6664
Breast cancer (BC) is a complex disease and obesity is a well-known risk factor for its development, especially after menopause. Several studies have shown Single Nucleotide Polymorphisms (SNPs) linked to overweight and obesity, such as: rs1121980 (T/C) and rs9939609 (A/T) in Fat Mass and Obesity Associated gene (FTO) and rs17782313 (T/C) in Melanocortin 4 Receptor gene (MC4R). Thus, we aimed to investigate the association between these obesity-related SNPs and BC risk. One hundred BC patients and 148 healthy women from Santa Catarina, Brazil entered the study. SNPs were genotyped using Taqman assays. For statistical analyses SNPStats and SPSS softwares were used. Association analyses were performed by logistic regression and were adjusted for age and Body mass index (BMI). Multiple SNPs inheritance models (log-additive, dominant, recessive, codominant) were performed to determine odds ratios (ORs), assuming 95 % confidence interval (CI) and P value = 0.05 as the significance limit. When analyzed alone, FTO rs1121980 and rs9939609 did not show significant associations with BC development, however MC4R rs17782313 showed increased risk for BC even after adjustments (P-value = 0.032). Interestingly, the interaction of FTO and MC4R polymorphisms showed a powerful association with BC. We observed a 4.59-fold increased risk for woman who have the allele combination C/T/C (FTO rs1121980/FTO rs9939609/MC4R rs17782313) (P-value = 0.0011, adjusted for age and BMI). We found important and unpublished associations between these obesity-related genes and BC risk. These associations seem to be independent of their effect on BMI, indicating a direct role of the interaction between FTO and MC4R polymorphisms in BC development. 相似文献
995.
André R. L. Damásio Cleiton Márcio Pinto Braga Lívia B. Brenelli Ana Paula Citadini Fernanda Mandelli Junio Cota Rodrigo Ferreira de Almeida Victor Hugo Salvador Douglas Antonio Alvaredo Paixao Fernando Segato Adriana Zerlotti Mercadante Mario de Oliveira Neto Wanderley Dantas do Santos Fabio M. Squina 《Applied microbiology and biotechnology》2013,97(15):6759-6767
The structural polysaccharides contained in plant cell walls have been pointed to as a promising renewable alternative to petroleum and natural gas. Ferulic acid is a ubiquitous component of plant polysaccharides, which is found in either monomeric or dimeric forms and is covalently linked to arabinosyl residues. Ferulic acid has several commercial applications in food and pharmaceutical industries. The study herein introduces a novel feruloyl esterase from Aspergillus clavatus (AcFAE). Along with a comprehensive functional and biophysical characterization, the low-resolution structure of this enzyme was also determined by small-angle X-ray scattering. In addition, we described the production of phenolic compounds with antioxidant capacity from wheat arabinoxylan and sugarcane bagasse using AcFAE. The ability to specifically cleave ester linkages in hemicellulose is useful in several biotechnological applications, including improved accessibility to lignocellulosic enzymes for biofuel production. 相似文献
996.
997.
Aura Silva Emília Sousa Andreia Palmeira Pedro Amorim David A. Ferreira 《Journal of biomolecular structure & dynamics》2013,31(11):1864-1875
Background: Hydroxyethyl starch (HES) is one of the most used colloids for intravascular volume replacement during anesthesia. Aim: To investigate the existence of a chemical interaction between HES and the anesthetic propofol by in vitro propofol dosing, computational docking, and examination of a complex between propofol and HES by infrared (IR), ultraviolet (UV), and 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Methods: Ten samples with human plasma mixed with HES or lactated Ringers (n?=?5 for each fluid) were prepared, and the propofol free fraction was quantified until 50?min, using gas chromatography-mass spectrometry. The docking study was performed between HES and propofol and compared with controls. The binding affinities between HES and the small molecules were evaluated by binding free energy approximation (ΔGb, kJ?mol?1). The IR, UV, and NMR spectra were measured for propofol, HES, and a mixture of both obtained by the kneading method. Results: Propofol concentrations were significantly lower in the HES samples than in the LR samples (p?=?.021). The spectroscopic characterization of propofol combined with HES revealed differences in spectra and docking studies reinforced a potential interaction between propofol and HES. Conclusions: Propofol and HES form a complex with different physical-bio-chemical behavior than the single drugs, which may be an important drug interaction. Further studies should evaluate its clinical effects. 相似文献
998.
Eduardo Chicote Ana M Garcia M Isabel Sarro Petra I Lorenzo Felipe Montero 《Biofouling》2013,29(1):35-42
Microbial activity in spent nuclear fuel pools which contain ultrapure and radioactive water has been previously observed. The aim of the present research was to isolate and identify the microorganisms attached to the nuclear pool wall of a Spanish nuclear power plant. Amplification of 16S rDNA fragments from the culturable microorganisms by PCR using universal primers for the domain ‘Bacteria’, followed by Denaturing Gradient Gel Electrophoresis analysis revealed the presence of six different bacteria. The complete gene for 16S rDNA of each one was sequenced and identified as belonging to three different phylogenetic groups, viz. β-Proteobacteria, Actinomycetales and the Bacillus/Staphylococcus group. A fungus was also found and identified as Aspergillus fumigatus by sequencing the D2 region of the large subunit rDNA gene. The isolation of these microorganisms in oligotrophic and radioactive conditions is of great interest due to the possibility of their use in bioremediation processes of radionuclide-contaminated environments. 相似文献
999.
Clarissa M. Comim Bruna P. Mendonça Diogo Dominguini Andreza L. Cipriano Amanda V. Steckert Giselli Scaini Mariz Vainzof Emílio L. Streck Felipe Dal-Pizzol João Quevedo 《Molecular neurobiology》2013,48(1):71-77
Congenital muscular dystrophies present mutated gene in the LARGE mice model and it is characterized by an abnormal glycosylation of α-dystroglycan (α-DG), strongly implicated as having a causative role in the development of central nervous system abnormalities such as cognitive impairment seen in patients. However, the pathophysiology of the brain involvement remains unclear. Therefore, the objective of this study is to evaluate the oxidative damage and energetic metabolism in the brain tissue as well as cognitive involvement in the LARGE(myd) mice model of muscular dystrophy. With this aim, we used adult homozygous, heterozygous, and wild-type mice that were divided into two groups: behavior and biochemical analyses. In summary, it was observed that homozygous mice presented impairment to the habituation and avoidance memory tasks; low levels of brain-derived neurotrophic factor (BDNF) in the prefrontal cortex, hippocampus, cortex and cerebellum; increased lipid peroxidation in the prefrontal cortex, hippocampus, striatum, and cerebellum; an increase of protein peroxidation in the prefrontal cortex, hippocampus, striatum, cerebellum, and cortex; a decrease of complex I activity in the prefrontal cortex and cerebellum; a decrease of complex II activity in the prefrontal cortex and cerebellum; a decrease of complex IV activity in the prefrontal cortex and cerebellum; an increase in the cortex; and an increase of creatine kinase activity in the striatum and cerebellum. This study shows the first evidence that abnormal glycosylation of α-DG may be affecting BDNF levels, oxidative particles, and energetic metabolism thus contributing to the memory storage and restoring process. 相似文献