Epidemiology of and prenatal molecular distinction between invasive and colonizing group B streptococci in The Netherlands and Taiwan.

The identification of markers for virulent group B streptococci (GBS) could guide prenatal prevention and intervention strategies. We compared the distribution of serotypes and potential pathogenicity islands (PPIs) between invasive and colonizing GBS. Colonizing and invasive strains from The Netherlands and Taiwan were serotyped. We used polymerase chain reaction (PCR) for the amplification of several new PPI markers. Several combinations of PPI-specific markers and serotypes were associated with invasiveness. For Dutch neonatal strains, a receiver operating characteristic (ROC) curve with serotype and five PPI markers showed an area under the curve (AUC) of 0.963 (95% confidence interval [CI] 0.935-0.99). For Taiwanese neonatal strains, serotype and four different PPI markers resulted in an ROC curve with an AUC of 0.894 (95% CI 0.826-0.963). PPI-specific and serological markers can distinguish local neonatal invasive GBS strains from colonizing ones. Apparently, there are clear regional differences in the GBS epidemiology and infection potential of clones.

The inducible lactose operator-repressor system is functional in the whole animal.

Mouse liver cell lines that bear a stably integrated lactose operon repressor (lacI) gene and a Ha-ras gene linked to a lactose operator-containing SV40 early promoter were generated. When grown in medium containing more than 0.1 mM isopropyl beta-D-thiogalactoside (IPTG), the Ha-ras gene was induced up to 20-fold. Maximum induction of Ha-ras gene expression occurred after 12 h of exposure. The tumorigenicity of these cell lines in syngeneic mice was enhanced when the mice were maintained on drinking water containing 12.5 mM IPTG. Ha-ras gene expression in tumors was strongly induced in the presence of IPTG in vivo. Induction of Ha-ras gene expression in mice was consistently observed after 48 hr of exposure to drinking water containing IPTG. This system provides an approach for studying the function of oncogene in vivo as well as other genes of interest.

Expression pattern of nuclear p53 is unique in COS-1 cells.

As p53 is transcriptionally inactive in COS-1 cells, we felt it would be interesting to study the relative time course of expression of nuclear p53 and the onset of S phase. Our results indicated that the expression of nuclear p53 lagged behind the onset of S phase in COS-1 cells. In addition, rapid nuclear expression of p53, probably resulting from nuclear translocation, occurred immediately after the addition of serum into COS1 cells. No such phenomena were found in B104-1 and BHK cells.

Transmission of human immunodeficiency virus through bone transplantation: a case report.

Human immunodeficiency virus (HIV) can be transmitted through tissue or organ transplantation. Since 1988, eight cases of bone transplantation-associated HIV infection have been reported. We describe a 34-year-old woman with osteoarthritis, who was hospitalized in 1996 because of painful locomotion and deformity in the right knee. An old fracture of the femur and genu varum in the right knee was repaired by open reduction and internal fixation, with allogeneic bone transplantation for defect reconstruction. Five months later, she presented at another hospital with pain and swelling of the right thigh, where screening for HIV was positive. The transmission was tracked to a 50-year-old man with no history of HIV screening, from whom the femoral head was procured when he underwent a hip replacement for left femoral neck fracture. This is the first reported case of HIV infection through bone transplantation in Taiwan, and the preventable nature of this transmission should be underscored.

Cloning of a LEU gene and an ARS site of Rhodotorula glutinis.

Genomic library of DNA from an extracellular protease-producing yeast strain, Rhodotorula glutinis K-24, was constructed, using Escherichia coli plasmid vector PBR322. A LEU gene from R. glutinis was cloned, and found to complement leu- mutations in E. coli and Saccharomyces cerevisiae. In E. coli, the LEU gene in the cloned yeast DNA fragment was efficiently expressed when inserted into the vector in one orientation. In S. cerevisiae, the R. glutinis LEU gene was efficiently expressed when inserted into a shuttle vector YEP13 in both orientations, suggesting that the isolated R. glutinis DNA fragment contains a promotor sequence of R. glutinis in front of the LEU gene. In addition, our data suggests that the cloned LEU fragment also contains an ARS (autonomously replication sequence) site of R. glutinis that could function in S. cerevisiae.

Non-clostridial gas gangrene caused by Klebsiella pneumoniae: a case report.

A 45-y-old man was hospitalized due to pain and swelling of the right leg for 3 d. Bullae developed with gas formation involving multiple compartments of the entire limb 46 h later. Klebsiella pneumoniae was recovered from blood and surgical specimens. The patient died on Day 8 despite amputation and antibiotic therapy.