排序方式: 共有83条查询结果,搜索用时 15 毫秒
11.
Isabel C.M. Fensterseifer Mário R. Felício Eliane S.F. Alves Marlon H. Cardoso Marcelo D.T. Torres Carolina O. Matos Osmar N. Silva Timothy K. Lu Maurício V. Freire Natan C. Neves Sónia Gonçalves Luciano M. Lião Nuno C. Santos William F. Porto Cesar de la Fuente-Nunez Octavio L. Franco 《生物化学与生物物理学报:生物膜》2019,1861(7):1375-1387
Infections caused by Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa foremost among them, constitute a major worldwide health problem. Bioinformatics methodologies are being used to rationally design new antimicrobial peptides, a potential alternative for treating these infections. One of the algorithms used to develop antimicrobial peptides is the Joker, which was used to design the peptide PaDBS1R6. This study evaluates the antibacterial activities of PaDBS1R6 in vitro and in vivo, characterizes the peptide interaction to target membranes, and investigates the PaDBS1R6 structure in contact with mimetic vesicles. Moreover, we demonstrate that PaDBS1R6 exhibits selective antimicrobial activity against Gram-negative bacteria. In the presence of negatively charged and zwitterionic lipids the structural arrangement of PaDBS1R6 transits from random coil to α-helix, as characterized by circular dichroism. The tertiary structure of PaDBS1R6 was determined by NMR in zwitterionic dodecylphosphocholine (DPC) micelles. In conclusion, PaDBS1R6 is a candidate for the treatment of nosocomial infections caused by Gram-negative bacteria, as template for producing other antimicrobial agents. 相似文献
12.
Daniel Constantino Yazbek Aluizio Barbosa de Carvalho Cinara Sá Barros Jose Osmar Medina Pestana Maria Eugênia F. Canziani 《PloS one》2016,11(4)
BackgroundCoronary calcification (CAC) is highly prevalent in kidney transplant recipients (KTRs) and has been associated with cardiovascular morbidity and mortality. Some studies have shown a reduction in CAC progression with statin therapy in the general and chronic kidney disease (CKD) populations.ResultsAt baseline, CAC was observed in 30% and 21% of patients in the statin and control groups, respectively (p = 0.39). The calcium score at baseline and its absolute and relative changes over 12 months of follow up were similar among the groups. In the statin group, total cholesterol (p < 0.001), low density lipoprotein cholesterol (p < 0.001) and triglycerides (p = 0.005) decreased, and the estimated glomerular function rate increased (p<0.001) significantly. CRP levels remained stable (p = 0.52) in the statin group but increased in the control group (p = 0.01). In the multivariate model, there was no difference in CAC progression between the groups (group effect p = 0.034; time-effect p = 0.23; interaction p = 0.74). Similar results were obtained when only patients with ≥ 10AU calcium score (calcified) were analyzed (group effect p = 0.051; time-effect p = 0.58; interaction p = 0.99).ConclusionAlthough statins reduce the levels of cholesterol, triglycerides, inflammation and improve graft function, the dose adopted in the current study did not delay CAC progression within 12 months of follow up.
Trial Registration
Brazilian Clinical Trials Registry RBR-32RFMB 相似文献13.
Silva Caio Mateus Ferrari Gustavo Duarte Alberici Luciane Carla Malaspina Osmar Moraes Karen C. M. 《Molecular and cellular biochemistry》2020,466(1-2):129-137
Molecular and Cellular Biochemistry - This study evaluated the cardioprotective effects of a miR-1275 mimic in a rat model of myocardial ischemia–reperfusion (I/R)-induced myocardial injury... 相似文献
14.
LS Tavares JV Rettore RM Freitas WF Porto AP Duque Jde L Singulani ON Silva Mde L Detoni EG Vasconcelos SC Dias OL Franco Mde O Santos 《Peptides》2012,37(2):294-300
Antimicrobial peptides (AMPs) are compounds that act in a wide range of physiological defensive mechanisms developed to counteract bacteria, fungi, parasites and viruses. These molecules have become increasingly important as a consequence of remarkable microorganism resistance to common antibiotics. This report shows Escherichia coli expressing the recombinant antimicrobial peptide Pg-AMP1 previously isolated from Psidium guajava seeds. The deduced Pg-AMP1 open reading frame consists in a 168bp long plus methionine also containing a His6 tag, encoding a predicted 62 amino acid residue peptide with related molecular mass calculated to be 6.98kDa as a monomer and 13.96kDa at the dimer form. The recombinant Pg-AMP1 peptide showed inhibitory activity against multiple Gram-negative (E. coli, Klebsiella pneumonia and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Staphylococcus epidermides) bacteria. Moreover, theoretical structure analyses were performed in order to understand the functional differences between natural and recombinant Pg-AMP1 forms. Data here reported suggest that Pg-AMP1 is a promising peptide to be used as a biotechnological tool for control of human infectious diseases. 相似文献
15.
Tadaiti Ozato Júnior José Osmar Gaspar Priscila Belintani 《Journal of Phytopathology》2009,157(9):573-575
The sequence of the central part (ORF2) of a Brazilian isolate of Southern bean mosaic virus (SBMVSP ) is described. This ORF is 2888 nt long and together with the previously-sequenced 5' and 3' ends provides the complete nucleotide sequence of this virus isolate. The SBMVSP RNA encodes four overlapping open reading frames (ORF1, ORF2a, ORF2b, ORF4) and has a genome organization similar to that of the Cocksfoot mottle sobemovirus . 相似文献
16.
The quorum-sensing interfering RNAIII-inhibiting peptide (RIP) YSPXTNF and its synthetic analogues YSPWTNF and YSPITNF have been shown to prevent and suppress diseases caused by Staphylococcus aureus at different body sites in different animal models. This study was designed to investigate histopathologically the therapeutic efficacy of lead peptide RIP YSPWTNF-NH(2) in the subcutaneous air sac murine model of acquired S. aureus sepsis. Two experimental protocols were evaluated: an infection/therapy protocol, for which twenty BALB/c mice per group were infected with a subcutaneous inoculum of S. aureus strain ATCC 25923 ( [Formula: see text] colony forming units) that were either pretreated or not with 150microg of peptide RIP, and a safety protocol, for which three uninfected mice per group received treatment with either 150microg of peptide RIP or saline. Therapeutic efficacy was assessed by clinical examination for a period of 20 days and histopathology at 12, 24, 36, 48, 96 and 168h after inoculation. Treatment safety was assessed histopathologically at 24, 48 and 264h after inoculation. Subcutaneous administration of uninfected control mice with a single dose of peptide RIP YSPWTNF caused no significant histopathology in most organs examined, except for slight to moderate lung and liver congestions. In contrast to the situation with the untreated infected control group mice that presented with histopathological alterations consistent with the diagnosis of rapidly progressive and highly erosive disease (100% mortality by day 3), treatment of infected animals with peptide RIP YSPWTNF had a profound therapeutic effect on survival rate (67% by day 20) and on disease progression. The histopathological examination confirmed the clinical findings showing that extensive tissue damage at the site of the infection and in organs were greatly suppressed in the peptide RIP-treated animals. 相似文献
17.
Spices can present high microbial counts and Clostridium perfringens, Bacillus cereus, Salmonella and Shigella, among others have been isolated from spices. C. perfringens is an important pathogen agent causing, among other diseases, enteritis in humans caused by C. perfringens enterotoxin (CPE) which causes human food poisoning and enterotoxemia in domestic animals. The aims of the present work were (i) to establish the hygienic sanitary quality of some spices in San Luis, Argentina; (ii) to determine the presence of C. perfringens in these spices by means of the most probable number (MPN) and count on plate methods; (iii) to characterize the enterotoxigenic strains of C. perfringens by PCR and immunological methods such as reverse passive latex agglutination (RPLA) and (iv) to type by PCR C. perfringens strains isolated. A total of 115 samples of spices, 67 of which were purchased in local retail stores and 48 domestically collected were analysed. Total aerobe counts on tryptone glucose yeast extract agar medium of the 115 samples were between <10 and 10(6) CFU/g. The colifecal counts using Mac Conkey broth of the 115 samples were <4-10(3)CFU/g, with 28 samples (24.34%) exceeding the limit established by the Spanish Alimentary Code (10 CFU/g) while 2 samples (1.73%) had a sulfite reducing anaerobe load above standard limits. A total of 14 C. perfringens strains (12.17%) were isolated and characterized from 115 samples by the standard biochemical tests. Four of which (28.60%) turned out to be enterotoxigenic by PCR and RPLA. In order to type C. perfringens strains based on their main toxins, the 14 strains were analysed by PCR. All strains belonged to type A. All RPLA positive strains were cpe(+) by PCR. The percentage of enterotoxigenic strains was more elevated that those reported in other studies for this type of sample. These results indicate that sanitary conditions in different production stages of species must be improved to reduce health hazards. The high percentage (24.34%) of samples with colifecal values above standard limits is an indication of deficient sanitary conditions. These results suggest the need to provide legislation on the sanitary and hygienic quality of spices in our country. 相似文献
18.
Aline da Silva Cruz Elaine C. M. da Silva-Zacarin Odair C. Bueno Osmar Malaspina 《Cell biology and toxicology》2010,26(2):165-176
Morphological alterations, by means of histological and ultrastructural analysis, have been used to determine the effects
of boric acid and fipronil on midgut tissues of honeybee worker, Apis mellifera L. larvae. In order to observe possible morphological alterations in the midgut, two groups of bioassays were performed. In
the first one, the larvae were chronically treated with different concentrations of boric acid added to the food (1.0, 2.5
and 7.5 mg/g). In the second group, the larvae were fed with diets containing different concentrations of fipronil (0.1 and
1 μg/g) and compared with control groups without these chemical compounds. In the first bioassay, the larvae were collected
on day 3 and in the second bioassay on day 4, when the mortality rate obtained in the toxicological bioassay was not very
high. The larval midguts were removed and processed for morphological analyses using a light and transmission electron microscopy.
We observed cytoplasmic vacuolizations, with the absence of autophagic vacuoles, and chromatinic compacting in most of the
cells in the groups treated with pesticides. The morphological alterations were far greater in the larvae treated with boric
acid than in the larvae treated with fipronil. Our data suggest that the midgut cell death observed was in response to boric
acid and fipronil action. This study significantly improves the understanding of the toxicological effect of these insecticides
from the ecotoxicological perspective. 相似文献
19.
20.