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101.
102.
Human infections caused by Brevibacterium casei, formerly CDC groups B-1 and B-3. 总被引:3,自引:0,他引:3 下载免费PDF全文
E Gruner A G Steigerwalt D G Hollis R S Weyant R E Weaver C W Moss M Daneshvar J M Brown D J Brenner 《Journal of clinical microbiology》1994,32(6):1511-1518
Forty-one clinical strains of CDC coryneform groups B-1 and B-3 were compared biochemically, by analysis of cell wall sugars, amino acids, and cellular fatty acids, and by DNA relatedness to the type strains of Brevibacterium casei, Brevibacterium epidermidis, and Brevibacterium linens. Twenty-two strains were shown to be B. casei, while five other strains formed a phenotypically inseparable genomospecies in the same genus. The remaining isolates were genetically heterogeneous, and most are probably members of the genus Brevibacterium. They were not further identified, but they were biochemically distinguishable from B. casei. Eleven of the clinical strains of B. casei were isolated from blood, and two each were isolated from cerebrospinal fluid and from pleural fluid. At least five isolates were from multiple blood or cerebrospinal fluid cultures. To our knowledge, these strains are the first described clinical isolates identified as B. casei, which was previously considered to be a nonpathogenic species. 相似文献
103.
Phenotypic characteristics, fatty acid composition, and isoprenoid quinone content of CDC group IIg bacteria. 下载免费PDF全文
Eleven strains of eugonic, nonoxidative, gram-negative rods isolated from clinical specimens formed a distinct group that was designated CDC group IIg. Five of the 11 isolates were from wounds. The phenotypic characteristics of CDC group IIg were most similar to those of Weeksella species, with the major difference being that CDC group IIg strains grew on MacConkey agar in 1 to 2 days, did not hydrolyze gelatin, and did not produce urease. All 11 strains of CDC group IIg possessed a distinct fatty acid profile that was characterized by large amounts (19 to 29%) of 18:1 omega 7c, 16:0, and 16:1 omega 7c, moderate amounts (6 to 10%) of 3-OH-14:0 and 14:0, and smaller amounts (1 to 2%) of 18:2, 18:0, and 3-OH-16:0. This fatty acid profile differs from those of Weeksella species by the absence of branched-chain fatty acids. CDC group IIg contains ubiquinone-8, as opposed to menaquinone-6 in Weeksella species. The isolates were susceptible to a variety of antimicrobial agents, including the aminoglycosides, tetracyclines, quinolones, sulfonamides, and polymyxin B. 相似文献
104.
Food-initiated outbreak of methicillin-resistant Staphylococcus aureus analyzed by pheno- and genotyping. 总被引:3,自引:4,他引:3 下载免费PDF全文
J Kluytmans W van Leeuwen W Goessens R Hollis S Messer L Herwaldt H Bruining M Heck J Rost N van Leeuwen 《Journal of clinical microbiology》1995,33(5):1121-1128
An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) involving 27 patients and 14 health-care workers (HCW) was studied. The outbreak started in the hematology unit of the University Hospital Rotterdam, Dijkzigt, The Netherlands, and spread to the surgical unit. Twenty-one patients (77.8%) developed clinical disease, and five died. Subsequently, MRSA was detected in food and in the throat of one of the HCW who prepared food for hematology patients. Food contaminated by an HCW most likely caused the first case of MRSA septicemia. This route of transmission has not been described before. The outbreak strain was probably transmitted to the surgical unit by a colonized nurse, where it caused an explosive outbreak. Airborne probably transmitted to the surgical unit by a colonized nurse, where it caused an explosive outbreak. Airborne MRSA transmission played an important role in disseminating the organism. The outbreak was controlled within 6 months by intensifying surveillance, temporarily closing the affected wards, treating carriers, and instituting an MRSA ward outside the hospital. Phage typing, insertion sequence probing, protein A gene typing, and DNA fingerprinting by PCR revealed that all outbreak-related isolates were identical. By pulsed-field gel electrophoresis, all but one of the outbreak-related isolates were determined to be identical. Protein A gene typing identified numerous (11) repeat units in all outbreak-related isolates, which supports the suggestion that the outbreak strain may have been more virulent and more transmissible than other MRSA strains. Pheno- and genotyping studies underlined the value of DNA fingerprinting methods for investigation of MRSA epidemiology. Optimal discriminatory power was achieved by combining the results of four genotyping methods. 相似文献
105.
Rapid detection and identification of human adenovirus species by adenoplex, a multiplex PCR-enzyme hybridization assay 下载免费PDF全文
Pehler-Harrington K Khanna M Waters CR Henrickson KJ 《Journal of clinical microbiology》2004,42(9):4072-4076
Human adenoviruses (AdV) have been implicated in a wide variety of diseases and are ubiquitous in populations worldwide. These agents are of concern particularly in immunocompromised patients, children, and military recruits, resulting in severe disease or death. Clinical diagnosis of AdV is usually achieved through routine viral cell culture, which can take weeks for results. Immunofluorescence and enzyme-linked immunosorbent assay-based techniques are more timely but lack sensitivity. The ability to distinguish between the six different AdV species (A to F) is diagnostically relevant, as infections with specific AdV species are often associated with unique clinical outcomes and epidemiological features. Therefore, we developed a multiplex PCR-enzyme hybridization assay, the Adenoplex, using primers to the fiber gene that can simultaneously detect all six AdV species A through F in a single test. The limit of detection (LOD) based on the viral 50% tissue culture infective dose/ml for AdV A, B, C, D, E, and F was 10(-2), 10(-1), 10(-1), 10(-2), 10(-1), and 10(-2), respectively. Similarly, the LOD for the six DNA controls ranged from 10(2) to 10(3) copies/ml. Twelve common respiratory pathogens were tested with the Adenoplex, and no cross-reactivity was observed. We also validated our assay using clinical specimens spiked with different concentrations of AdV strains of each species type and tested by multiplex PCR and culture. The results demonstrated an overall sensitivity and specificity of Adenoplex of 100%. This assay can be completed in as few as 5 h and provides a rapid, specific, and sensitive method to detect and subtype AdV species A through F. 相似文献
106.
Pfaller MA Diekema DJ Messer SA Boyken L Hollis RJ Jones RN;International Fungal Surveillance Participant Group 《Journal of clinical microbiology》2003,41(1):78-83
We determined the in vitro susceptibilities of 314 strains of Candida spp., representing 13 species rarely isolated from blood, to posaconazole and voriconazole as well as four licensed systemic antifungal agents (amphotericin B, flucytosine, fluconazole, and itraconazole). The organisms included 153 isolates of C. krusei, 67 isolates of C. lusitaniae, 48 isolates of C. guilliermondii, 10 isolates of C. famata, 10 isolates of C. kefyr, 6 isolates of C. pelliculosa, 5 isolates of C. rugosa, 4 isolates of C. lipolytica, 3 isolates of C. dubliniensis, 3 isolates of C. inconspicua, 2 isolates of C. sake, and 1 isolate each of C. lambica, C. norvegensis, and C. zeylanoides. MIC determinations were made by the National Committee for Clinical Laboratory Standards reference broth microdilution method and Etest (amphotericin B). Resistance to both amphotericin B and fluconazole was observed in strains of C. krusei, C. lusitaniae, C. guilliermondii, C. inconspicua, and C. sake. Resistance to amphotericin B, but not to fluconazole, was also observed among isolates of C. kefyr and C. rugosa. Posaconazole and voriconazole were active (MIC, < or = 1 micro g/ml) against 94 to 100% of these isolates. In contrast to the more common species of Candida causing bloodstream infection, these rare species appear to be less susceptible to the currently licensed systemic antifungal agents, with the exception of voriconazole. Continued surveillance will be necessary to detect the emergence of these species as more prevalent, resistant pathogens. The new triazoles appear to offer acceptable coverage of uncommon Candida sp. bloodstream infections. 相似文献
107.
Max J. Kurz Konstantinos Pothakos Sakeena Jamaluddin Melissa Scott-Pandorf Chris Arellano Yuen-Sum Lau 《Neuroscience letters》2007
The purpose of this investigation was to determine if a chronic Parkinson's disease mouse model will display less certainty in its gait pattern due to basal ganglia dysfunction. A chronic Parkinson's disease mouse model was induced by injecting male C57/BL mice with 10 doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (25 mg/kg) (MPTP) and probenecid (250 mg/kg) (P) over 5 weeks. This chronic model produces a severe and persistent loss of nigrostriatal neurons resulting in dopamine depletion and locomotor impairment. The control mice were treated with probenecid alone. Fifteen weeks after the last MPTP/P treatment, the mice were videotaped in the sagittal plane with a digital camera (60 Hz) as they ran on a motorized treadmill at a speed of 10 m/min. The indices of gait and gait variability were calculated. Stride length was significantly (p = 0.016) more variable in the chronic MPTP/P mice. Additionally, the chronic MPTP/P mice had a statistically less certain gait pattern when compared to the control mice (p = 0.02). These results suggest that variability in the gait pattern can be used to evaluate changes in neural function. Additionally, our results imply that disorder of the basal ganglia results in less certainty in modulating the descending motor command that controls the gait pattern. 相似文献
108.
Field evaluation of the efficacy and immunogenicity of recombinant hepatitis B vaccine without HBIG in newborn Vietnamese infants 总被引:4,自引:0,他引:4
A study involving more than 2,000 infants was conducted in Vietnam to assess the field effectiveness and immunogenicity of recombinant hepatitis B vaccine given at birth, 1 month, 2 months, without concomitant hepatitis B immune globulin (HBIG). All received a 5 microg dose of H-B-VAX II at birth. Infants born to non-carrier mothers (Group 1; N = 1798) then received 2.5 microg doses at 1 and 2 months of age, while infants of HBeAg-negative (Group 2; N = 125) or HBeAg-positive (Group 3; N = 88) carrier mothers received 5 microg doses. No Group 1 or 2 vaccinees were infected. In Group 3, 12 (14.6%) of 82 infants did become infected (estimated efficacy 84%). 98.0-98.6% of uninfected infants who were tested for anti-HBs developed a seroprotective concentration > or = 10 IU/L. In hyperendemic Vietnam, where routine maternal screening and passive-active prophylaxis of high-risk infants with vaccine plus HBIG is not feasible, administration of vaccine alone to all newborns may control effectively HBV infection. 相似文献
109.
Absence of proteinase-activated receptor-1 signaling affords protection from bleomycin-induced lung inflammation and fibrosis 下载免费PDF全文
Howell DC Johns RH Lasky JA Shan B Scotton CJ Laurent GJ Chambers RC 《The American journal of pathology》2005,166(5):1353-1365
Activation of the coagulation cascade is commonly observed in the lungs of patients with both acute and chronic inflammatory and fibrotic lung disorders, as well as in animal models of these disorders. The aim of this study was to examine the contribution of the major thrombin receptor, proteinase-activated receptor-1 (PAR-1), during the acute inflammatory and chronic fibrotic phases of lung injury induced by intratracheal instillation of bleomycin in mice. Inflammatory cell recruitment and increases in bronchoalveolar lavage fluid (BALF) protein were attenuated by 56 +/- 10% (P < 0.05) and 53 +/- 12% (P < 0.05), respectively, in PAR-1-deficient (PAR-1-/-) mice compared with wild-type (WT) mice. PAR-1-/- mice were also protected from bleomycin-induced pulmonary fibrosis with total lung collagen accumulation reduced by 59 +/- 5% (P < 0.05). The protection afforded by PAR-1 deficiency was accompanied by significant reductions in pulmonary levels of the potent PAR-1-inducible proinflammatory and profibrotic mediators, monocyte chemoattractant protein-1 (MCP-1), transforming growth factor-beta-1 (TGF-beta1), and connective tissue growth factor/fibroblast-inducible secreted protein-12 (CTGF/FISP12). In addition, PAR-1 was highly expressed in inflammatory and fibroproliferative lesions in lung sections obtained from patients with fibrotic lung disease. These data show for the first time that PAR-1 signaling plays a key role in experimentally induced lung injury, and they further identify PAR-1 as one of the critical receptors involved in orchestrating the interplay between coagulation, inflammation, and remodeling in response to tissue injury. 相似文献
110.
Rorden C Driver J 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,137(3-4):487-496
Research on visual attention has demonstrated that covert attention can be focused on particular locations within one hemifield,
but that a specific "meridian" cost may also be found for shifting attention between hemifields. These issues have received
less consideration for audition, even though reliable behavioral measures for the effects of spatial attention on hearing
are now available. We examined the spatial distribution of covert attention in an auditory task following spatially non-predictive
peripheral auditory cues (which should induce exogenous attention shifts), or following symbolic central cues that predicted
the likely location for the auditory target (to induce endogenous attention shifts). In both cases, we found that attention
can be focused not only on one hemifield versus another, but also within one hemifield in an auditory task. However, there
was no unequivocal evidence for a meridian effect in audition.
Electronic Publication 相似文献