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1.
Sacramento Doralice Rodrigues Coelho Rosalie Reed Rodrigues Wigg Márcia Dutra Toledo Luna Linhares Luiz Fernando de Matos dos Santos Marta Gonçalves Azevedo Soares Semêdo Luzia Teixeira de Ribeiro da Silva Antonio Jorge 《World journal of microbiology & biotechnology》2004,20(3):225-229
A promising producer of bioactive compounds isolated from a Brazilian tropical soil was tested for its range of antimicrobial
activities. Strain 606, classified as Streptomyces sp., could not be identified up to species level, suggesting a possible new taxon. The supernatant and 10 extracts and fractions,
obtained by extraction and chromatographic techniques, presented antimicrobial activity using antibiograms. The methanolic
fraction was highly active against pathogenic bacteria, phytopathogenic fungi and the human pathogenic yeast Candida albicans. It also possessed high antiviral activity inhibiting the propagation of an acyclovir-resistant herpes simplex virus type
1 strain on HEp-2 cells at non-cytotoxic concentration. The strong cytotoxic effect suggests an antitumour action.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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A method is described which allows a clear demonstration of capillaries and muscle fibers in the heart and skeletal muscle of experimental animals. The fluorescent dyes fluorescein isothiocyanate (FITC) and lissamine rhodamine B 200 (RB 200) were conjugated with a protein of high (gamma-globulin) and low (myoglobin) molecular weight, respectively, and were intravitally injected into the vascular system of rats. FITC globulin distributes itself in the intravasal space and RB 200 myoglobin in the extracellular. In histological sections the capillary lumina and the borderlines of the muscular fibers can be clearly identified and quantitatively evaluated because of the selective fluorescence in the respective structures. 相似文献
4.
Mandana Nikpour Dafna D Gladman Dominique Ibanez Paula J Harvey Murray B Urowitz 《Arthritis research & therapy》2010,12(3):R125
Introduction
Total cholesterol (TC) and blood pressure (BP) are likely to take a dynamic course over time in patients with systemic lupus erythematosus (SLE). This would have important implications in terms of using single-point-in-time measurements of these variables to assess coronary artery disease (CAD) risk. The objective of this study was to describe and quantify variability over time of TC and BP among patients with SLE and to determine their correlates. 相似文献5.
Virginia Edgcomb William Orsi John Bunge Sunok Jeon Richard Christen Chesley Leslin Mark Holder Gordon T Taylor Paula Suarez Ramon Varela Slava Epstein 《The ISME journal》2011,5(8):1344-1356
Microbial diversity and distribution are topics of intensive research. In two companion papers in this issue, we describe the results of the Cariaco Microbial Observatory (Caribbean Sea, Venezuela). The Basin contains the largest body of marine anoxic water, and presents an opportunity to study protistan communities across biogeochemical gradients. In the first paper, we survey 18S ribosomal RNA (rRNA) gene sequence diversity using both Sanger- and pyrosequencing-based approaches, employing multiple PCR primers, and state-of-the-art statistical analyses to estimate microbial richness missed by the survey. Sampling the Basin at three stations, in two seasons, and at four depths with distinct biogeochemical regimes, we obtained the largest, and arguably the least biased collection of over 6000 nearly full-length protistan rRNA gene sequences from a given oceanographic regime to date, and over 80 000 pyrosequencing tags. These represent all major and many minor protistan taxa, at frequencies globally similar between the two sequence collections. This large data set provided, via the recently developed parametric modeling, the first statistically sound prediction of the total size of protistan richness in a large and varied environment, such as the Cariaco Basin: over 36 000 species, defined as almost full-length 18S rRNA gene sequence clusters sharing over 99% sequence homology. This richness is a small fraction of the grand total of known protists (over 100 000–500 000 species), suggesting a degree of protistan endemism. 相似文献
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The aquatic larvae of the genus Chironomus (Diptera, Insecta) contain at least 12 different hemoglobin (Hb) variants in their hemolymph. In the present study we have analysed the structure and part of the nucleotide sequence of a Hb gene cluster cloned from the genomic DNA of Chironomus thummi piger. The cluster contains probably 6 different genes, separated by intergenic regions of various lengths. The nucleotide sequence of three putative Hb genes including the intergenic regions is presented. The inferred amino-acid sequences show clearly that two of these putative genes code for subvariants of the Hb variant VIIB. The third gene codes for a so far unknown Hb protein. As known already for other chironomid Hb genes, there are no intron sequences present in the coding regions. 相似文献
8.
E Ortega Rincón J M Marchena J J García A Schmidt T Schulz I Malpica A B Rodríguez C Barriga H Michna H L?tzerich 《Journal of applied physiology》2001,91(3):1067-1072
Flow cytometer measurements were made of the basal variations in peripheral blood functional monocytes and granulocytes over the course of a training season (January to November) of a cycling team. Parallel determinations were made of plasma concentration of catecholamines (chromatography) and cortisol (RIA) in a search for neuroendocrine markers. The results showed the greatest phagocytic capacity to occur in the central months (March, May, and July), coinciding with the greatest number and highest level of competitive events with good correlation with a peak in epinephrine during these months (r(2) = 0.998 for monocytes and r(2) = 0.674 for granulocytes). No good correlations were found between phagocytosis and norepinephrine or cortisol. The highest values for phagocytosis and epinephrine concentration were found in May. These results suggest that blood epinephrine concentration could be a good neuroendocrine marker of sportspeople's phagocytic response. 相似文献
9.
Summary A male fetus of a pregnancy known to be at risk for X-linked mental retardation with fragile site Xq27 was found to be affected by demonstrating the marker X-chromosome in five of 180 (2.8%) of metaphases derived from amniocytes cultured in medium 199. The results were confirmed in fetal lymphocytes (25 of 86 metaphases, i.e. 29%), and fetal fibroblasts (five of 100 metaphases when cultured in medium 199, and 14 of 100 after exposure to methotrexate for 43 h).This work was supported in part by a research grant from the Deutsche Forschungsgemeinschaft 相似文献
10.
Acyltransferase-catalyzed cleavage of arachidonic acid from phospholipids and transfer to lysophosphatides in lymphocytes and macrophages 总被引:2,自引:0,他引:2
The cleavage of fatty acyl moieties from phospholipids was compared in intact cells and homogenates of mouse lymphocytes (thymocytes, spleen cells) and macrophages. Liberation of free arachidonic acid during incubations of intact cells was only detectable in the presence of albumin. Homogenization of prelabeled thymocytes and further incubation of these homogenates at 37 degrees C resulted in a pronounced decrease of phospholipid degradation and cleavage of arachidonoyl residues, while further incubation of homogenates from prelabeled macrophages produced a greatly increased phospholipid degradation. Homogenates of macrophages but not those of thymocytes contain substantial activities of phospholipase A2 detectable using exogenous radiolabeled substrates. These findings indicate that in thymocytes cleavage of arachidonic acid from phosphatidylcholine is an active process that is not catalyzed by phospholipase A2. Addition of CoA and lysophosphatidylethanolamine to prelabeled thymocyte homogenates induced a fast breakdown of phosphatidylcholine and transfer of arachidonic acid to phosphatidylethanolamine, as in seen during incubations of intact thymocytes or macrophages. The transfer is restricted to arachidonic acid and does not require addition of ATP. Sodium cholate, a known inhibitor of the acyl-CoA:lysophosphatide acyltransferase, completely inhibited this transfer reaction. These results suggest that the CoA-mediated, ATP-independent breakdown of phosphatidylcholine and transfer of arachidonic acid is catalyzed by the acyl-CoA:lysophosphatide acyltransferase operating in reverse. 相似文献