From January 1995 to September 1996, 14 isolates of Sphingomonas paucimobilis, including 11 from clinical specimens from six patients with nosocomial infection and three from environmental sources, were collected. Two...
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From January 1995 to September 1996, 14 isolates of Sphingomonas paucimobilis, including 11 from clinical specimens from six patients with nosocomial infection and three from environmental sources, were collected. Two of the six patients had intravascular catheter-related bacteremia and one each had bacteremic biliary tract infection, urinary tract infection, ventilator-associated pneumonia, and wound infection. The S. paucimobilis isolates were identified according to biochemical profiles established with use of the API 20NE system and Vitek GNI card and the characteristic cellular fatty acid chromatogram. Ten biotypes, 11 antibiograms (by the Etest), and 12 random amplified polymorphic DNA (RAPD) patterns (by arbitrarily primed polymerase chain reaction) were identified. The identical biotype, antibiogram, and RAPD pattern of the two isolates (one each from blood and bile) from a patient with biliary tract infection indicated the invasiveness of the organism. Two patients with intravascular catheter-related bacteremia had isolates of this organism repeatedly recovered, and these isolates had heterogeneous RAPD patterns. The present study highlights the wide distribution in hospital environments of various clones of S. paucimobilis, which may cause recurrent infections by a single strain or several episodes of infection due to two or more clones of this organism in hospitalized patients.
The activated c-Ha-ras oncogene induced AP1-site DNA-binding activity in F9 cells. This induction appeared to be due, at least in part, to the induction of c-jun transcription. Both activated c-Ha-ras and c-jun induce...
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The activated c-Ha-ras oncogene induced AP1-site DNA-binding activity in F9 cells. This induction appeared to be due, at least in part, to the induction of c-jun transcription. Both activated c-Ha-ras and c-jun induced the differentiation of F9 cells to endoderm-like cells. Thus, AP1 appears to play a key role in the initial stage of F9 cell differentiation.
Despite the great attention lavished on science and technology by a diversity of academic disciplines and specialties, surprisingly little is known about the pre-eminent vectors for scientific knowledge and the foremo...
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Despite the great attention lavished on science and technology by a diversity of academic disciplines and specialties, surprisingly little is known about the pre-eminent vectors for scientific knowledge and the foremost practitioners of technology - ordinary engineers. Elite (and therefore, by definition, unrepresentative) cases aside, what is known about engineers normally concerns either their aggregate numbers and gross levels of education, or their professional societies. The inquiry described here seeks to depict in somewhat richer detail one engineering discipline - petroleum engineering - and to examine in a general way how that discipline fits into the particular society of which it was a part. The point is simply that, far from being the on-dimensional 'nerds' of stereotype, engineers are multidimensional social entities - and that, in constructing their roles in social action, who they are very likely matters every bit as much as what they know. [ABSTRACT FROM AUTHOR]
Bacterial counts on the liquid phase of an anaerobic, fixed-bed digester, treating a deproteinated, prefermented cheese whey substrate, were conducted on two different media under aerobic and facultative conditions. A...
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Bacterial counts on the liquid phase of an anaerobic, fixed-bed digester, treating a deproteinated, prefermented cheese whey substrate, were conducted on two different media under aerobic and facultative conditions. Average counts of 16.6×106 and 26.5×106 ml?1 were obtained on the two media, with the nutritionally poorer of the two media giving the highest average count. Seventy-five isolates from both media, incubated aerobically as well as in anaerobic jars, were obtained. These isolates as well as 13 reference strains were phenotypically characterized. The similarities between cultures were calculated using the similarity coefficient of Sokal and Michener [16]. The organisms were clustered using the unweighted pair group method, and the results presented as a simplified dendrogram. The isolates could be divided into 3 main groups: gram-negative fermentative rods, mainlyEnterobacter, Klebsiella, andCitrobacter, withKlebsiella as the predominant genus; gram-positive bacteria, mainly enterococci; and gram-negative nonfermentive rods of the generaPseudomonas, Alcaligenes, andAcinetobacter. All the enterobacteria and enterococci were able to produce acetic acid, an intermediate in methanogenesis.
Reproducible and discriminating typing methods are required for epidemiological investigations. Numerical typing systems analyse patterns obtained in various ways by calculating similarity coefficients between isolate...
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Reproducible and discriminating typing methods are required for epidemiological investigations. Numerical typing systems analyse patterns obtained in various ways by calculating similarity coefficients between isolates. In the present study, various measures of the efficiency of a numerical typing system are quantified. These include reproducibility, accuracy, and discrimination power. Three different numerical typing methods for Escherichia coli were compared using these measures: (a) Biotyping with API 50 CH system, (b) Biochemical fingerprinting with the API 50 CH system and (c) Biochemical fingerprinting with the PhP-EC system. Biotyping qualitatively measures the results of a set of biochemical reactions as + or -. Biochemical fingerprinting also uses biochemical reactions, but the tests are scored quantitatively by measuring the kinetics and intensity of each reaction. It was found that biotyping yielded poor reproducibility. When biochemical fingerprinting analysis was used with the API 50 CHE system the reproducibility and the discrimination was good. The PhP-EC system for biochemical fingerprinting showed equal reproducibility but was superior to the API 50 CH system with regard to discrimination power.
The host specificity of yeast-yeast interactions was investigated for two yeast types, represented by six pairs of Pichia membranifaciens clade yeasts (Pichia membranifaciens or Issatchenkia occidentalis) with apicula...
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The host specificity of yeast-yeast interactions was investigated for two yeast types, represented by six pairs of Pichia membranifaciens clade yeasts (Pichia membranifaciens or Issatchenkia occidentalis) with apiculate yeasts (Kloeckera apis, Kloeckera africana, or Saccharomycodes ludwigii), commonly found in fruits. Competitive interactions between the two types were detected in both ripe tomato and guava. fruit pulp. The differences in growth rates and carrying capacities depended on fruit type (host) and culture conditions (monocultures versus bicultures). These differences were probably due to nutrient composition of each fruit. Pichia membranifaciens did not show host dependent responses, but the apiculate yeasts and Issatchenkia occidentalis did. Depending on yeast strain and culture conditions (i.e., monoculture or biculture), carbon, nitrogen, and vitamins were investigated as potential limiting growth factors in guava fruit. Both singular and multiple limiting nutrients were implicated.
The Arctic pole of inaccessibility (API), defined as the point on the Arctic Ocean that is farthest from any land, is commonly asserted to lie at 84 degrees 03 N, 174 degrees 51 W. We show that the true position is 85...
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The Arctic pole of inaccessibility (API), defined as the point on the Arctic Ocean that is farthest from any land, is commonly asserted to lie at 84 degrees 03 N, 174 degrees 51 W. We show that the true position is 85 degrees 48 N, 176 degrees 09 E, over 200 km from the traditional location. The reason for this error is unknown.
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