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C.J. Donskey C.K. Hoyen S.M. Das S. Farmer M. Dery & R.A. Bonomo 《Letters in applied microbiology》2001,33(1):84-88
AIMS: A mouse model of vancomycin-resistant enterococcus (VRE) stool colonization was used to study the effect of Bacillus coagulans, a biotherapeutic agent, on the density of colonization. METHODS AND RESULTS: VRE-colonized mice received orally administered B. coagulans (107 cfu) or saline daily for four days. For one VRE strain, the density of VRE at one and four days after treatment was 1.4 log10cfu x g(-1) lower in experimental vs. control mice (P=0.03), and 35% of experimental vs. 0% of control mice had no detectable VRE four days after treatment (P=0.03). For two additional strains, there was no statistically significant reduction of VRE density in the B. coagulans groups. CONCLUSION: B. coagulans therapy reduced the density of colonization for one of three VRE strains tested. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests a potential role for biotherapeutic agents as a means to reduce the density of VRE intestinal colonization. 相似文献
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The new higher level classification of eukaryotes with emphasis on the taxonomy of protists 总被引:23,自引:0,他引:23
Adl SM Simpson AG Farmer MA Andersen RA Anderson OR Barta JR Bowser SS Brugerolle G Fensome RA Fredericq S James TY Karpov S Kugrens P Krug J Lane CE Lewis LA Lodge J Lynn DH Mann DG McCourt RM Mendoza L Moestrup O Mozley-Standridge SE Nerad TA Shearer CA Smirnov AV Spiegel FW Taylor MF 《The Journal of eukaryotic microbiology》2005,52(5):399-451
This revision of the classification of unicellular eukaryotes updates that of Levine et al. (1980) for the protozoa and expands it to include other protists. Whereas the previous revision was primarily to incorporate the results of ultrastructural studies, this revision incorporates results from both ultrastructural research since 1980 and molecular phylogenetic studies. We propose a scheme that is based on nameless ranked systematics. The vocabulary of the taxonomy is updated, particularly to clarify the naming of groups that have been repositioned. We recognize six clusters of eukaryotes that may represent the basic groupings similar to traditional "kingdoms." The multicellular lineages emerged from within monophyletic protist lineages: animals and fungi from Opisthokonta, plants from Archaeplastida, and brown algae from Stramenopiles. 相似文献
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Constantine KL Krystek SR Healy MD Doyle ML Siemers NO Thanassi J Yan N Xie D Goldfarb V Yanchunas J Tao L Dougherty BA Farmer BT 《Protein science : a publication of the Protein Society》2005,14(6):1472-1484
CFE88 is a conserved essential gene product from Streptococcus pneumoniae. This 227-residue protein has minimal sequence similarity to proteins of known 3D structure. Sequence alignment models and computational protein threading studies suggest that CFE88 is a methyltransferase. Characterization of the conformation and function of CFE88 has been performed by using several techniques. Backbone atom and limited side-chain atom NMR resonance assignments have been obtained. The data indicate that CFE88 has two domains: an N-terminal domain with 163 residues and a C-terminal domain with 64 residues. The C-terminal domain is primarily helical, while the N-terminal domain has a mixed helical/extended (Rossmann) fold. By aligning the experimentally observed elements of secondary structure, an initial unrefined model of CFE88 has been constructed based on the X-ray structure of ErmC' methyltransferase (Protein Data Bank entry 1QAN). NMR and biophysical studies demonstrate binding of S-adenosyl-L-homocysteine (SAH) to CFE88; these interactions have been localized by NMR to the predicted active site in the N-terminal domain. Mutants that target this predicted active site (H26W, E46R, and E46W) have been constructed and characterized. Overall, our results both indicate that CFE88 is a methyltransferase and further suggest that the methyltransferase activity is essential for bacterial survival. 相似文献
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Jones DJ Jukes-Jones R Verschoyle RD Farmer PB Gescher A 《Bioorganic & medicinal chemistry》2005,13(24):6727-6731
To study the biological effects of quercetin, authentic products of quercetin metabolism are required as standards. The synthesis of quercetin sulfate standards is thus described. Quercetin was reacted with a 10-fold molar excess of sulfur trioxide-N-triethylamine, and the products were analyzed by HPLC and mass spectrometry. Four monosulfates and three disulfates were identified, and structural inferences were drawn by 1H NMR spectrometry of HPLC peak isolates. Analysis of the urine of rats that had received quercetin (1.9 g/kg po) yielded a single peak, which by comparison with the products of the reaction between quercetin and sulfur trioxide-N-triethylamine was identified as quercetin 3′-O-sulfate. 相似文献
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Yao W Farmer R Cooper R Chmielewski PA Tian XY Setterberg RB Jee WS Lundy MW 《Journal of musculoskeletal & neuronal interactions》2006,6(3):277-283
Current published results on whether statins have beneficial effects on bone metabolism have been conflicting so far. In order to further investigate if statins were promising candidates for the treatment for osteoporosis, we conducted a study in which rats were ovariectomized (OVX) at 6 months of age, allowed to lose bone for 60 days and followed by oral administration of simvastatin at the dose levels of 0.3-10 mg/kg/d for 60 days. PGE2 (6 mg/kg) was used as a positive control. Study endpoints included bone histomorphometry on the proximal tibial metaphysis (PTM) and the tibial diaphysis (TX), dual-energy X-ray absorptiometry on the right femur and micro computed tomography (ICT) on the 5th lumbar vertebra (LV). After 120 days of OVX, cancellous bone lost by 80% in the PTM and 18% in the LV accompanied by increased bone formation and resorption. Simvastatin at all dose levels did not affect bone volume, bone formation rate and bone erosion surface when compared to 120 day ovariectomized animals at all bone sites studied. By contrast, PGE2 restored cancellous and cortical bone area to sham control levels. In conclusion, this study demonstrated that unlike PGE2, oral administration of simvastatin did not have effects on cancellous or cortical bone formation and resorption; and consequently was not able to prevent further bone loss or restore bone mass in the osteopenic, OVX rats. 相似文献