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排序方式: 共有463条查询结果,搜索用时 500 毫秒
31.
P. Tremonte A. Reale T. Di Renzo L. Tipaldi A. Di Luccia R. Coppola E. Sorrentino M. Succi 《Letters in applied microbiology》2010,51(5):586-594
Aims: To evaluate interactions between Lactobacillus sakei and coagulase negative cocci (CNC) (Staphylococcus xylosus and Kocuria varians) and to investigate the influence of these interactions on their own proteolytic activity. Methods and Results: Interactions occurring between strains of Lact. sakei and CNC were assessed by spectrophotometric analysis. The growth of 35 strains of Lact. sakei, used as indicators, was compared to that obtained combining the same strains with growing cells or cell‐free supernatants of 20 CNC (18 Staph. xylosus and 2 K. varians). The proteolytic activity expressed by single strains or by their combinations was assessed on sarcoplasmic protein extracts by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis. The results evidenced that interactions are able to affect not only the growth but also the in vitro proteolytic activity of Lact. sakei and CNC used in combination. Conclusions: A relationship between the presence of interactions among useful strains and the strength of technological characteristics, such as proteolysis, was defined. Significance and Impact of the Study: The study highlighted that CNC are able to stimulate the growth of some Lact. sakei strains. At the same time, this interaction positively influences the proteolytic activity of strains used in combination. Given the importance of proteolysis during the ripening of fermented meats, this phenomenon should be taken into account to select meat starter cultures. 相似文献
32.
Functional yet balanced reactivity to Candida albicans requires TRIF, MyD88, and IDO-dependent inhibition of Rorc 总被引:2,自引:0,他引:2
33.
NO-induced neuroprotection in ischemic preconditioning stimulates mitochondrial Mn-SOD activity and expression via Ras/ERK1/2 pathway 总被引:2,自引:0,他引:2
34.
Giraldi C Noto A Tenuta R Greco F Perugini D Dodaro S Spadafora M Lo Bianco AM Savino O Papalia T Greco R Bonofiglio R 《The new microbiologica》2007,30(2):127-130
Nephropathy caused by poliomavirus (BKVAN) in transplant recipients is responsible for the loss of the transplanted organ. In this study we suggest a non-invasive diagnostic protocol for the early identification of BKVAN during follow-up treatments. In 117 kidney transplant recipients follow-up was performed every three months during a two year period after transplantation and a positive screening result was confirmed and assessed by quantitative assays (BKV DNA load in plasma and urine). The definitive diagnosis of BKV requires allograft biopsy. Of the 117 patients 4 had BKVAN (3.4%), and the consequential reduction of immunosuppression improved kidney function and plasma clearance of the virus was achieved. 相似文献
35.
Tremonte P Succi M Reale A Di Renzo T Sorrentino E Coppola R 《Journal of applied microbiology》2007,103(3):743-751
AIMS: To evaluate the interactions of Staphylococcus xylosus on Kocuria varians strains isolated from fermented meat products. Methods and Results: Interactions were assessed in vitro by agar spot test, agar well diffusion assay and spectrophotometric assay. The growth of K. varians (five strains) alone was compared with that in the presence of growing cells of S. xylosus (50 strains) or in the presence of heat-treated or untreated supernatants of S. xylosus. Sixteen strains stimulated the growth of K. varians K4, while four strains inhibited the K4 strain. Heated cell-free supernatants of S. xylosus did not have any effect on K. varians. The proteolytic activity of single strains or their combinations was assessed in vitro and in vivo by sodiumdodecylsulfate-polyacrylamide gel electrophoresis of sarcoplasmic protein extracts. Combinations of stimulatory strains of S. xylosus and K. varians showed a higher proteolytic activity compared with that of S. xylosus or K. varians alone. CONCLUSIONS: The interactions between strains may influence both the growth of the co-cultured strains and proteolysis, technologically relevant characteristics. SIGNIFICANCE AND IMPACT OF THE STUDY: The study of interactions between coagulase-negative cocci may guide the formulation of mixed strain starters for the production of fermented sausages. 相似文献
36.
A new species of freshwater crab, Potamonautes
isimangaliso
sp. n., is described from the western shores of False Bay, Hluhluwe, within the iSimangaliso Wetland Park, South Africa. While bearing a superficial resemblance to Potamonautes
lividus, the new species has been found to be genetically distinct, diverging from the former by 7.4–7.8% in mtDNA. Potamonautes
isimangaliso most closely resembles Potamonautes
lividus, but is distinguished by a unique suite of carapace characters, colouration, and size. The new species also lives in close association with oxygen-poor, fresh ephemeral pans, while the habitat of Potamonautes
lividus is well above the surface water line of the closest water body. An updated identification key for the Potamonautes species of South Africa is provided. 相似文献
37.
Di Renzo F Rossi F Bacchetta R Prati M Giavini E Menegola E 《Birth defects research. Part B, Developmental and reproductive toxicology》2011,92(3):189-194
BACKGROUND: The use of nonmammal models in teratological studies is a matter of debate and seems to be justified if the embryotoxic mechanism involves conserved processes. Published data on mammals and Xenopus laevis suggest that azoles are teratogenic by altering the endogenous concentration of retinoic acid (RA). The expression of some genes (Shh, Ptch‐1, Gsc, and Msx2) controlled by retinoic acid is downregulated in rat embryos exposed at the phylotypic stage to the triazole triadimefon (FON). In order to propose X. laevis as a model for gene‐based comparative teratology, this work evaluates the expression of Shh, Ptch‐1, Gsc, and Msx2 in FON‐exposed X. laevis embryos. METHODS: Embryos, exposed to a high concentration level (500 µM) of FON from stage 13 till 17, were examined at stages 17, 27, and 47. Stage 17 and 27 embryos were processed to perform quantitative RT‐PCR. RESULTS: The developmental rate was never affected by FON at any considered stage. FON‐exposed stage 47 larvae showed the typical craniofacial malformations. A significant downregulation of Gsc was observed in FON‐exposed stage 17 embryos. Shh, Ptch‐1, Msx2 showed a high fluctuation of expression both in control and in FON‐exposed samples both at stages 17 and 27. CONCLUSION: The downregulation of Gsc mimics the effects of FON on rat embryos, showing for this gene a common effect of FON in the two vertebrate classes. The high fluctuation observed in the gene expression of the other genes, however, suggests that X. laevis at this stage has limited utility for gene‐based comparative teratology. Birth Defects Res (Part B) 92:189–194, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
38.
Yilmaz P Kottmann R Field D Knight R Cole JR Amaral-Zettler L Gilbert JA Karsch-Mizrachi I Johnston A Cochrane G Vaughan R Hunter C Park J Morrison N Rocca-Serra P Sterk P Arumugam M Bailey M Baumgartner L Birren BW Blaser MJ Bonazzi V Booth T Bork P Bushman FD Buttigieg PL Chain PS Charlson E Costello EK Huot-Creasy H Dawyndt P DeSantis T Fierer N Fuhrman JA Gallery RE Gevers D Gibbs RA San Gil I Gonzalez A Gordon JI Guralnick R Hankeln W Highlander S Hugenholtz P Jansson J Kau AL Kelley ST 《Nature biotechnology》2011,29(5):415-420
Here we present a standard developed by the Genomic Standards Consortium (GSC) for reporting marker gene sequences--the minimum information about a marker gene sequence (MIMARKS). We also introduce a system for describing the environment from which a biological sample originates. The 'environmental packages' apply to any genome sequence of known origin and can be used in combination with MIMARKS and other GSC checklists. Finally, to establish a unified standard for describing sequence data and to provide a single point of entry for the scientific community to access and learn about GSC checklists, we present the minimum information about any (x) sequence (MIxS). Adoption of MIxS will enhance our ability to analyze natural genetic diversity documented by massive DNA sequencing efforts from myriad ecosystems in our ever-changing biosphere. 相似文献
39.
40.
Mutyam V Puccetti MV Frisbie J Goldstein DL Krane CM 《Journal of experimental zoology. Part A, Ecological genetics and physiology》2011,315(7):424-437
Cope's gray treefrog, Hyla chrysoscelis,is a freeze-tolerant anuran which accumulates and distributes glycerol as a cryoprotectant before freezing. We hypothesize that HC-3, an aquaglyceroporin member of the MIP family of water pores, may play an important role in the process of freeze tolerance by mediating transmembrane passage of glycerol and water during cold-acclimation. The objectives of this study were two-fold: to examine HC-3 protein abundance and cellular localization in erythrocytes from cold- and warm-acclimated frogs and to develop and characterize an erythrocyte cell culture system for examining HC-3 gene regulation. Compared with warm-acclimated frogs, erythrocytes from cold-acclimated frogs had higher HC-3 protein expression and enhanced plasma membrane localization. Furthermore, erythrocytes from cold- and warm-acclimated frogs maintained in culture at 4 and 20°C exhibited time- and temperature-dependent regulation of HC-3 expression and an increase in the abundance of high molecular weight immunoreactive species within 24?hr of culture at 20°C. Deglycosylation of erythrocyte proteins resulted in the disappearance of the high molecular weight species, indicating that HC-3 is post-translationally modified by N-linked glycosylation. Erythrocytes cultured in media containing glycerol also showed an increased abundance of the high molecular weight bands and enhanced plasma membrane localization of HC-3, suggesting a role for glycerol in regulating HC-3 subcellular trafficking. Thus, the development of this erythrocyte cell culture system from H. chrysoscelis opened an opportunity to study the properties of cells with changing expression of an aquaglyceroporin, HC-3, and to explore the factors regulating that expression. 相似文献