Antimicrobic susceptibility and plasmid profile analysis as identity tests for multiple blood isolates of coagulase-negative staphylococci

We compared a disk diffusion antimicrobic susceptibility panel with plasmid DNA profiles as tests for identity of 106 isolates of coagulase-negative staphylococci cultured from the blood of 45 patients on multiple occasions. The antimicrobic panel included penicillin, oxacillin, clindamycin, trimethoprim-sulfamethoxazole, chloramphenicol, tetracycline, tobramycin, kanamycin, and gentamicin. Nineteen patterns of antimicrobic susceptibility were found. The most common pattern was present in 25% of the isolates, and at least one isolate from 31% of the patients had this pattern. Forty-seven distinct plasmid DNA profiles were found. The most common plasmid profile was present in 8.5% of the isolates, and at least one isolate from 15% of the patients had this profile. Twenty-eight patients had multiple isolates that were identical by plasmid profile analysis. Twenty-seven (96%) of these patients had isolates that were also identical by antimicrobic susceptibility. Nineteen patients had multiple isolates that were different by plasmid profile analysis. In 18 (95%) of these patients, the isolates were also different by antimicrobic susceptibility. Although plasmid DNA profile analysis is a more discriminating tool, these data confirm that a selected disk diffusion antimicrobic susceptibility panel may be used to screen multiple blood isolates of coagulase-negative staphylococci for identity or differences.

Occurrence of chromosome- or plasmid-mediated aerobactin iron transport systems and hemolysin production among clonal groups of human invasive strains of Escherichia coli K1

The incidence of the aerobactin system and the genetic location of aerobactin genes were investigated in Escherichia coli K1 neonatal isolates belonging to different clonal groups. A functional aerobactin system was found in all members of the O7 MP3, O1 MP5, O1 MP9, and O18 MP9 clonal groups examined and also in K1 strains having O6, O16, and O75 lipopolysaccharide types, which are less frequently associated with neonatal infections. In contrast, the aerobactin system was not detected in strains from the O18 MP6 clone. The combined results of plasmid and colony hybridization experiments showed that the aerobactin genes were located on the chromosome in the majority (75%) of the aerobactin-producing K1 isolates, the genetic location of the aerobactin genes was closely correlated with the outer membrane protein profile rather than the O lipopolysaccharide type, the K1 strains harboring a chromosome-mediated aerobactin system did not possess colicin V genes, and five of six K1 isolates possessing a plasmid-borne aerobactin system contained colicin V genes which were located on the same plasmids carrying the aerobactin genes. The comparison of hemolysin production with possession of the aerobactin system in virulent clones of E. coli K1 strains showed that all of the aerobactin-producing strains from the O18 MP9 and O7 MP3 clonal groups did not synthesize hemolysin, whereas 11 of 12 aerobactin-nonproducing O18 MP6 isolates were hemolytic. Of the K1 strains examined, 92.5% possessed either the aerobactin system or the ability to produce hemolysin or both.

Denver - A City Profile

Denver has emerged from the 1990s as a city region experiencing rapid growth. This has been fuelled by a vibrant local economy, which has adjusted itself from dependency on an earlier oil boom to greater reliance on the information and communications technology sector. The current planning and development challenges are dominated by the need to deal with urban sprawl and pressured transportation infrastructure. The contemporary restructuring of the physical fabric of Denver is marked by a progressive downtown revitalisation effort and a number of space extensive brownfield development projects. The interplay of state and local governments with commercial interests and citizens is a powerful dynamic in shaping these negative and positive outcomes.

Optimisation of source/drain extension region profile for suppression of short channel effects in sub-50 nm DG SOI MOSFETs with high- k gate dielectrics

Novel technology dependent scaling parameters i.e. spacer to gradient ratio and effective channel length (Leff) are proposed for source/drain engineered DG MOSFET, and their significance in minimizing short channel effects (SCES) in high-k gate dielectrics is discussed in detail. Results show that a high-k dielectric should be associated with a higher spacer to gradient ratio to minimise SCEs The analytical model agrees with simulated data over the entire range of spacer widths, doping gradients, high-k gate dielectrics and effective channel lengths.

Effect of eucaloric high- and low-sucrose diets with identical macronutrient profile on insulin resistance and vascular risk - A randomized controlled trial

The long-term impact of dietary carbohydrate type, in particular sucrose, on insulin resistance and the development of diabetes and atherosclerosis is not established. Current guidelines for the healthy population advise restriction of sucrose intake. We investigated the effect of high- versus low-sucrose diet (25 vs. 10%, respectively, of total energy intake) in 13 healthy subjects aged 33 +/- 3 years (mean +/- SE), BMI 26.6 +/- 0.9 kg/m(2), in a randomized crossover design with sequential 6-week dietary interventions separated by a 4-week washout. Weight maintenance, eucaloric diets with identical macronutrient profiles and fiber content were designed. All food was weighed and distributed. Insulin action was assessed using a two-step euglycemic clamp; glycemic profiles were assessed by the continuous glucose monitoring system and vascular compliance by pulse-wave analysis. There was no change in weight across the study. Peripheral glucose uptake and suppression of endogenous glucose production were similar after each diet. Glycemic profiles and measures of vascular compliance did not change. A rise in total and LDL cholesterol was observed. In this study, a high-sucrose intake as part of an eucaloric, weight-maintaining diet had no detrimental effect on insulin sensitivity, glycemic profiles, or measures of vascular compliance in healthy nondiabetic subjects.