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排序方式: 共有362条查询结果,搜索用时 15 毫秒
111.
Pereira L Carvalho MR Fonseca CG Lima SS Cerqueira EM Jorge W Castro MC 《Genetics and molecular research : GMR》2011,10(4):3552-3558
Polymorphisms in the TP53 gene codon 72 (Arg72Pro) influence apoptosis induction and DNA damage repair. We evaluated how variants of protein p53 (p53Arg and p53Pro) affect cell death and DNA damage repair by analyzing the frequencies of karyorrhexis and micronuclei. There were significant differences in the frequency of karyorrhexis between the three p53 genotypes (Arg/Arg, Arg/Pro, and Pro/Pro), between samples taken before and after radiotherapy, and between patients and controls. The frequency of micronucleated cells increased significantly after radiotherapy. There were no significant differences in the micronucleus frequency in healthy tissues of these patients compared to controls, or in the comparisons between the three genotypes. We conclude that Arg72Pro polymorphism influences cell apoptotic capacity. This is the first study investigating karyorrhexis and micronuclei, as indicators of apoptosis after radiotherapy, and how these indicators are influenced by the TP53 polymorphism Arg72Pro. 相似文献
112.
Enhanced mitochondrial biogenesis promoted by eNOS activation is believed to play a central role in the beneficial effects of calorie restriction (CR). Since treatment of mice with dinitrophenol (DNP) promotes health and lifespan benefits similar to those observed in CR, we hypothesized that it could also impact biogenesis. We found that DNP and CR increase citrate synthase activity, PGC-1α, cytochrome c oxidase and mitofusin-2 expression, as well as fasting plasma levels of NO• products. In addition, eNOS and Akt phosphorylation in skeletal muscle and visceral adipose tissue was activated in fasting CR and DNP animals. Overall, our results indicate that systemic mild uncoupling activates eNOS and Akt-dependent pathways leading to mitochondrial biogenesis. 相似文献
113.
C. Almeida J. M. Sousa R. Rocha L. Cerqueira S. Fanning N. F. Azevedo M. J. Vieira 《Applied and environmental microbiology》2013,79(20):6293-6300
Despite the emergence of non-O157 Shiga toxin-producing Escherichia coli (STEC) infections, E. coli serotype O157 is still the most commonly identified STEC in the world. It causes high morbidity and mortality and has been responsible for a number of outbreaks in many parts of the world. Various methods have been developed to detect this particular serotype, but standard bacteriological methods remain the gold standard. Here, we propose a new peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) method for the rapid detection of E. coli O157. Testing on 54 representative strains showed that the PNA probe is highly sensitive and specific to E. coli O157. The method then was optimized for detection in food samples. Ground beef and unpasteurized milk samples were artificially contaminated with E. coli O157 concentrations ranging from 1 × 10−2 to 1 × 102 CFU per 25 g or ml of food. Samples were then preenriched and analyzed by both the traditional bacteriological method (ISO 16654:2001) and PNA-FISH. The PNA-FISH method performed well in both types of food matrices with a detection limit of 1 CFU/25 g or ml of food samples. Tests on 60 food samples have shown a specificity value of 100% (95% confidence interval [CI], 82.83 to 100), a sensitivity of 97.22% (95% CI, 83.79 to 99.85%), and an accuracy of 98.33% (CI 95%, 83.41 to 99.91%). Results indicate that PNA-FISH performed as well as the traditional culture methods and can reduce the diagnosis time to 1 day. 相似文献
114.
Gleiciere Maia Silva Alice Rangel Cristiane Silveira Claudia Abreu Rodrigues Betânia Danielle Patrícia Cerqueira Macêdo Rejane Pereira Neves 《Mycopathologia》2013,176(3-4):233-236
Disseminated fusariosis is an uncommon clinical condition in immunocompromised patients. We report a fatal case of disseminated fusariosis secondary to neuroblastoma in a male patient, 15 years old, who underwent a bone marrow transplant. The patient was admitted to the pediatric intensive care unit (PICU) of a public hospital in Recife-PE, Brazil, presenting bone marrow aplasia, severe leukopenia, and thrombocytopenia. After 15 days, the patient developed right knee effusion. Synovial fluid and blood samples were analyzed at the Medical Mycology Laboratory of the Federal University of Pernambuco. Mycological diagnosis was based on the presence of hyaline septate hyphae on direct examination and the isolation of Fusarium oxysporum in culture, confirming the case of disseminated fusariosis. In vitro, the isolate showed fluconazole resistance and sensitivity to amphotericin B, anidulafungin, and voriconazole. Therapy with voriconazole in combination with liposomal amphotericin B led to an improved clinical response; however, due to underlying disease complications, the patient progressed to death. 相似文献
115.
Pascal Alonso Laurence Blondin Pierre Gladieux Frédéric Mahé Hervé Sanguin Romain Ferdinand Denis Filloux Eric Desmarais Frédérique Cerqueira Baihui Jin Huichuan Huang Xiahong He Jean-Benoit Morel Darren P. Martin Philippe Roumagnac Christian Vernière 《Environmental microbiology》2020,22(8):3429-3445
The Honghe Hani rice terraces system (HHRTS) is a traditional rice cultivation system where Hani people cultivate remarkably diverse rice varieties. Recent introductions of modern rice varieties to the HHRTS have significantly increased the severity of rice diseases within the terraces. Here, we determine the impacts of these recent introductions on the composition of the rice-associated microbial communities. We confirm that the HHRTS contains a range of both traditional HHRTS landraces and introduced modern rice varieties and find differences between the microbial communities of these two groups. However, this introduction of modern rice varieties has not strongly impacted the overall diversity of the HHRTS rice microbial community. Furthermore, we find that the rice varieties (i.e. groups of closely related genotypes) have significantly structured the rice microbial community composition (accounting for 15%–22% of the variance) and that the core microbial community of HHRTS rice plants represents less than 3.3% of all the microbial taxa identified. Collectively, our study suggests a highly diverse HHRTS rice holobiont (host with its associated microbes) where the diversity of rice hosts mirrors the diversity of their microbial communities. Further studies will be needed to better determine how such changes might impact the sustainability of the HHRTS. 相似文献
116.
Yin M. Yang Shailesh K. Gupta Kevin J. Kim Berit E. Powers Antonio Cerqueira Brian J. Wainger Hien D. Ngo Kathryn A. Rosowski Pamela A. Schein Courtney A. Ackeifi Anthony C. Arvanites Lance S. Davidow Clifford J. Woolf Lee L. Rubin 《Cell Stem Cell》2013,12(6):713-726
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117.
Hartwig DD Seixas FK Cerqueira GM McBride AJ Dellagostin OA 《Current microbiology》2011,62(4):1337-1341
The search for a vaccine capable of conferring heterologous protection, through the identification of conserved and cross-protective
antigens, remains an ongoing priority in leptospirosis research. In the present study, an in silico analysis was used to identify
potentially protective lipoproteins from Leptospira interrogans serovar Copenhageni. Eight putative lipoproteins were selected (LIC10009, LIC10054, LIC10091, LIC11058, LIC11567, LIC13059,
LIC13305, and LIC20172), cloned and expressed in Escherichia coli and purified by affinity chromatography. The recombinant proteins were used to inoculate mice and the subsequent humoral
immune response was evaluated by ELISA. Seven of the potential lipoproteins induced a significant IgG response. Furthermore,
all of the recombinant proteins were recognized by antibodies present in the sera of severe leptospirosis patients. These
putative lipoproteins exhibited potential for further evaluation as prospective vaccine candidates. 相似文献
118.
Kopp DA Elke DA Caddigan SC Raj A Rodriguez L Young MK Sparkes TC 《The Journal of parasitology》2011,97(6):1101-1105
In acanthocephalans, dispersal typically occurs when eggs that have been released in the intestines of definitive hosts are expelled with the feces. We examined whether the acanthocephalan Acanthocephalus dirus adopts a strategy of dispersal in which eggs are carried into the environment by gravid females. Using a combination of field surveys and lab-based experiments, we showed that the A. dirus female retained eggs as they passed out of the intestines and that these eggs could develop in intermediate hosts (sediment-dwelling isopods). Lab-based behavioral experiments revealed that the bodies of gravid females were attractive to foraging isopods. We propose that a strategy of egg dispersal could occur in A. dirus in which eggs are carried into the environment by females. This strategy could increase transmission success by dispersing eggs closer to the sediment, rather than in the water column, and by directing the feeding behavior of target hosts. 相似文献
119.
Coelho Cerqueira E Netz PA Diniz C Petry do Canto V Follmer C 《Bioorganic & medicinal chemistry》2011,19(24):7416-7424
Monoamine oxidase (MAO) catalyzes the oxidative deamination of biogenic and exogenous amines and its inhibitors have therapeutic value for several conditions including affective disorders, stroke, neurodegenerative diseases and aging. The discovery of 2,3,6-trimethyl-1,4-naphthoquinone (TMN) as a nonselective and reversible inhibitor of MAO, has suggested 1,4-naphthoquinone (1,4-NQ) as a potential scaffold for designing new MAO inhibitors. Combining molecular modeling tools and biochemical assays we evaluate the kinetic and molecular details of the inhibition of human MAO by 1,4-NQ, comparing it with TMN and menadione. Menadione (2-methyl-1,4-naphthoquinone) is a multitarget drug that acts as a precursor of vitamin K and an inducer of mitochondrial permeability transition. Herein we show that MAO-B was inhibited competitively by 1,4-NQ (Ki = 1.4 μM) whereas MAO-A was inhibited by non-competitive mechanism (Ki = 7.7 μM). Contrasting with TMN and 1,4-NQ, menadione exhibited a 60-fold selectivity for MAO-B (Ki = 0.4 μM) in comparison with MAO-A (Ki = 26 μM), which makes it as selective as rasagiline. Fluorescence and molecular modeling data indicated that these inhibitors interact with the flavin moiety at the active site of the enzyme. Additionally, docking studies suggest the phenyl side groups of Tyr407 and Tyr444 (for MAO-A) or Tyr398 and Tyr435 (for MAO-B) play an important role in the interaction of the enzyme with 1,4-NQ scaffold through forces of dispersion as verified for menadione, TMN and 1,4-NQ. Taken together, our findings reveal the molecular details of MAO inhibition by 1,4-NQ scaffold and show for the first time that menadione acts as a competitive and reversible inhibitor of human MAO. 相似文献
120.
Salazar-Sánchez L Leon MP Cartin M Schuster G Wulff K Schröder W Jiménez-Arce G Chacon R Herrmann FH 《Cell biochemistry and function》2007,25(6):739-745
In this study, eight common polymorphisms associated with venous thrombosis (VT) and thrombophilia factors were analyzed in a Costa Rican case-control study. With the use of polymerase chain reaction (PCR) methods the polymorphisms were detected in 120 patients and 133 controls (mean age <40 years old). It was concluded that a high level of fibrinogen, antiphospholipid antibodies, family history, and the genotype 34LeuLeu of FXIII OR 0.42 (0.20-0.89) showed a significant effect on the risk of VT.Associations between the risk of VT and genetic polymorphisms have been established. Some of these polymorphisms are highly prevalent in Caucasians, but there is a significant geographic variation in their prevalence among different populations. The results of this study support the protective effect of FXIII Val34Leu polymorphism in VT. These findings are consistent with previous reports that included other populations. 相似文献