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排序方式: 共有1582条查询结果,搜索用时 31 毫秒
971.
972.
Admilton Gonçalves de Oliveira Letícia Sayuri Murate Flavia Regina Spago Lucilene de Paula Lopes Jamile Priscila de Oliveira Beranger Juca Abramo Barrera San Martin Marco Antonio Nogueira João Carlos Palazzo de Mello Célia Guadalupe Tardeli de Jesus Andrade Galdino Andrade 《Biological Control》2011,56(2):125-131
In this work, we evaluated the antibiotic activity of metabolites produced by the Pseudomonas sp. LV strain and their effects on the cell morphology of the Xanthomonas citri pv. citri 306 strain (Xcc 306), which causes citrus canker lesions. The LV strain was cultivated, centrifuged, a cell-free supernatant was treated with dichloromethane and then concentrated, frozen in liquid nitrogen and lyophilized. The dichloromethane phase (DP) was fractionated by vacuum liquid chromatography (VLC) using six organic solvents with a crescent polarity. The antibiotic activity of the DP and all the fractions from VLC were tested against Xcc 306 and only the F3 fraction showed antimicrobial activity. The antibiotic activity of F3 was determined by minimum inhibitory concentration and the action on the cell morphology of Xcc 306 carried out in glass tubes with cell suspensions plus F3 solution sampled at three different times (one, three and six hours). The effects were analyzed by electron microscopy. Both the DP and F3 showed antibiotic activity against Xcc 306 in in vitro experiments. Electron microscopy showed that the F3 fraction completely disrupted the cell integrity after six hours. In a greenhouse experiment, the DP and F3 fraction (highly effective in in vitro experiments), reduced the formation of lesions by approximately 80% and 94%, respectively. 相似文献
973.
Estrada-de Los Santos P Vacaseydel-Aceves NB Martínez-Aguilar L Cruz-Hernández MA Mendoza-Herrera A Caballero-Mellado J 《Journal of microbiology (Seoul, Korea)》2011,49(6):867-876
The presence of Burkholderia, Cupriavidus, and Ralstonia species in northeastern Mexico was investigated. An analysis of the root surrounding soil from different agricultural plants
led to the isolation of Burkholderia and Cupriavidus species but no Ralstonia strains. Most Cupriavidus species were unknown and grouped into two clusters according to ARDRA profiles. The 16S rRNA sequence analysis showed that
the Cupriavidus isolates were highly related among them and with different Cupriavidus species with validated names. However, SDS-PAGE profiles were distinct among the different ARDRA profiles and to other Cupriavidus species examined, suggesting new species in the genus. This shows that Cupriavidus is more widely associated with plants than previously appreciated. The BCC isolate was 99% similar to B. cenocepacia by recA sequence analysis. Additionally, most Cupriavidus strains from the two largest groups grew on media containing up to 0.1 mg/ml of copper, 10.0 mg/ml arsenic and 1.0 mg/ml
zinc. Burkholderia strains grew on media containing up to 10.0 mg/ml zinc, 5.0 mg/ml arsenic and 0.1 mg/ml copper. 相似文献
974.
975.
976.
Ignacio Fernandez-Bances Marcos Perez-Basterrechea Silvia Perez-Lopez Daniel Nuñez Batalla Maria Angeles Fernandez Rodriguez Maria Alvarez-Viejo Amaia Ferrero-Gutierrez Yolanda Menendez-Menendez Jose Maria Garcia-Gala Dolores Escudero Jose Paz Aparicio Susana Carnero Lopez Pedro Lopez Fernandez Daniel Gonzalez Suarez Jesus Otero Hernandez 《Cytotherapy》2013,15(5):571-577
Background aimsLong-bone pseudoarthrosis is a major orthopedic concern because of numerous factors such as difficulty of the treatment, high recurrence, high costs and the devastating effects on the patients' quality of life, which sometimes ends in amputation. Although the “gold standard” for the treatment of this pathology is autologous bone grafting, which has high osteogenic, osteoconductive and osteoinductive properties, this treatment presents some restrictions such as the limited amount of bone that can be taken from the patient and donor site morbidity. Bone marrow mononuclear cells (BM-MNCs) comprise progenitor and stem cells with pro-angiogenic and pro-osteogenic properties. Allogenic cancellous bone graft is a natural and biodegradable osteoconductive and osteoinductive scaffold. Combination of these two components could mimic the advantages of autologous bone grafting while avoiding its main limitations.MethodsLong-bone pseudoarthrosis was treated in seven patients with autologous BM-MNCs from iliac crest combined with frozen allogenic cancellous bone graft obtained from the tissue bank.ResultsAll patients showed complete bone consolidation 5.3 ± 0.9 months (range, 2–9 months) after cell transplantation. Moreover, limb pain disappeared in all of them. The mean follow-up was 35.8 ± 4.6 months after transplantation (range, 24–51 months) without pseudoarthrosis recurrence or pain reappearing.ConclusionsCombination of autologous BM-MNCs and allogenic bone graft could constitute an easy, safe, inexpensive and efficacious attempt to treat long-bone pseudoarthrosis and non-union by reproducing the beneficial properties of autologous bone grafting while restricting its disadvantages. 相似文献
977.
978.
Ifeloju Dayo-Owoyemi Andre Rodrigues Melissa F. Landell Patricia Valente Ulrich G. Mueller Jesus Pais Ramos Fernando C. Pagnocca 《Mycological Progress》2013,12(1):157-165
In order to investigate the intraspecific variability in Hannaella kunmingensis, 11 isolates, including the type strain, were analyzed for their morphological and biochemical traits. The combined internal transcribed spacer region (ITS), D1/D2 domains of the large subunit rDNA (LSU), and cytochrome b gene were examined using phylogenetic and parsimony network analyses. Our investigations revealed differences in colony morphology as well as differences in 31 out of 64 phenotypic characteristics examined, including growth in lactose, vitamin free medium, xylitol, L-arabinitol, and nitrite. Growth in the presence of 0.1 % cycloheximide was also highlighted in H. kunmingensis. All the 11 strains were conspecific in the LSU; however, variations of about 2.5 % were found in the ITS while isolate CBS 8356 exhibited a 27.3 % divergence from the other strains in the cytochrome b gene. Parsimony network analysis revealed the existence of three haplotypes among the H. kunmingensis strains studied but excluded CBS 8356 from the network connecting these haplotypes. This study contributes to the knowledge of the intraspecific diversity of H. kunmingensis. To accommodate such intraspecific variations, an emendation of the species diagnosis is proposed. 相似文献
979.
Xuejuan Jiang J. Esteban Castelao David Vandenberg Angel Carracedo Carmen M. Redondo David V. Conti Jesus P. Paredes Cotoré John D. Potter Polly A. Newcomb Michael N. Passarelli Mark A. Jenkins John L. Hopper Steven Gallinger Loic Le Marchand María E. Martínez Dennis J. Ahnen John A. Baron Noralane M. Lindor Robert W. Haile Manuela Gago-Dominguez 《PloS one》2013,8(4)
Background
Recent genome-wide studies identified a risk locus for colorectal cancer at 18q21, which maps to the SMAD7 gene. Our objective was to confirm the association between SMAD7 SNPs and colorectal cancer risk in the multi-center Colon Cancer Family Registry.Materials and Methods
23 tagging SNPs in the SMAD7 gene were genotyped among 1,592 population-based and 253 clinic-based families. The SNP-colorectal cancer associations were assessed in multivariable conditional logistic regression.Results
Among the population-based families, both SNPs rs12953717 (odds ratio, 1.29; 95% confidence interval, 1.12–1.49), and rs11874392 (odds ratio, 0.80; 95% confidence interval, 0.70–0.92) were associated with risk of colorectal cancer. These associations were similar among the population- and the clinic-based families, though they were significant only among the former. Marginally significant differences in the SNP-colorectal cancer associations were observed by use of nonsteroidal anti-inflammatory drugs, cigarette smoking, body mass index, and history of polyps.Conclusions
SMAD7 SNPs were associated with colorectal cancer risk in the Colon Cancer Family Registry. There was evidence suggesting that the association between rs12953717 and colorectal cancer risk may be modified by factors such as smoking and use of nonsteroidal anti-inflammatory drugs. 相似文献980.
Herbert Gustavo Sim?es Ricardo Yukio Asano Marcelo Magalh?es Sales Rodrigo Alberto Vieira Browne Gisela Arsa Daisy Motta-Santos Guilherme Morais Puga Laila Candida de Jesus Lima Carmen Sílvia Grubert Campbell Octavio Luiz Franco 《PloS one》2013,8(11)
This study compared the plasma kallikrein activity (PKA), bradykinin concentration (BK), DesArg9-BK production, nitric oxide release (NO) and blood pressure (BP) response after moderate-intensity aerobic exercise performed by individuals with and without type 2 diabetes. Ten subjects with type 2 diabetes (T2D) and 10 without type 2 diabetes (ND) underwent three sessions: 1) maximal incremental test on cycle ergometer to determine lactate threshold (LT); 2) 20-min of constant-load exercise on cycle ergometer, at 90% LT and; 3) control session. BP and oxygen uptake were measured at rest and at 15, 30 and 45 min post-exercise. Venous blood samples were collected at 15 and 45 minutes of the recovery period for further analysis of PKA, BK and DesArg9-BK. Nitrite plus nitrate (NOx) was analyzed at 15 minutes post exercise. The ND group presented post-exercise hypotension (PEH) of systolic blood pressure and mean arterial pressure on the 90% LT session but T2D group did not. Plasma NOx increased ~24.4% for ND and ~13.8% for T2D group 15min after the exercise session. Additionally, only ND individuals showed increases in PKA and BK in response to exercise and only T2D group showed increased DesArg9-BK production. It was concluded that T2D individuals presented lower PKA, BK and NOx release as well as higher DesArg9-BK production and reduced PEH in relation to ND participants after a single exercise session. 相似文献