PubMed Health⌕ Search

Biomedical subjects

U van Treeck

Publications and source records attributed to U van Treeck.

8 recordsLinked to original sources
PubMed2005

Applying a case-crossover study design to examine transient exposures in the transmission of N. meningitidis.

BACKGROUND: Meningococcal disease is a serious public health problem with a case fatality of about 10%. Recent acquisition of the bacteria is generally regarded as an important risk factor for developing the invasive disease. A case-crossover study to examine the effect of transient exposures on the acute outcome, which is the acquisition of Neisseria meningitidis, was undertaken. METHODS: In the case-crossover design each case serves as its own matched control while case-times are compared to earlier time periods. Data from a longitudinal study was used for a case-crossover analysis. About 1910 students aged 14-19 were tested for meningococcal carriage and interviewed about potential risk factors. About 121 matched pairs of students who were non-carriers in the first survey and became carriers in the second were analysed. Mantel Haenszel Odds Ratios were calculated and a conditional logistic regression analysis was done. RESULTS: Both bivariate and multivariate analysis showed a significant association between meningococcal carriage and the predicting variables rhinitis, visits to cinema, and travelling abroad. While the adjusted results for rhinitis (OR: 0.33; 95% CI: 0.13-0.82) and cinema visits (OR: 0.17; 95% CI: 0.05-0.65) indicate a protective association, travelling abroad (OR: 3.50; 95% CI: 1.45-8.34) turned out as a risk factor. CONCLUSIONS: Transient exposures that trigger the infection with N. meningitidis are generally difficult to study. This case crossover study allows new insights in this process. For the interpretation of the results methodological issues and potential confounding (e.g., seasonal variation) need to be taken into account, especially while comparing the results with those from studies with traditional designs.

Adolescent↗
PubMed2003

[Infection surveillance in North Rhine-Westphalia--standard reports, barometer and early warning system].

The increasing significance of communicable diseases requires new surveillance tools. Modern electronic instruments in analysis and communication replace the former "handbased" statistics and allow the development of early warning systems. In North Rhine-Westphalia (NRW) the Institute of Public Health started an approach to develop a modular surveillance system prior to the the implementation of the new German infectious disease protection act. The first module called "Automated infectious disease notifications and information system (AIM+)" generates various standard hypertext reports which are published as "Infectious disease reports NRW" on the internet (www.loegd.nrw.de). In addition the infectious disease information is linked with a geographical information system (GIS) giving spatial and temporal patterns. The second module called "Infectious disease barometer NRW" offers a quick actual overview highlighting several selected diseases. It can be electronically sent out to any interested person. The third module "Early warning system" realizes an effective early detection system by combining six statistical procedures with a total of 11 separate methods. In case of detecting clusters and outbreaks it automatically generates warning reports to the responsible parties. All three modules together improve the epidemiological surveillance of the population in NRW, support the translation of information to prevention and control measures, and therefore strengthen epidemiological policy-making.

Communicable Disease Control↗
PubMed1983

Dissemination of streptomycin and sulfonamide resistance by plasmid pBP1 in Escherichia coli.

About one third of streptomycin resistance in Escherichia coli is mediated by APH-(3''). This enzyme is encoded by the plasmid pBP1 in 80% of all streptomycin resistant strains tested. pBP1, which in addition mediates sulfonamide resistance, has been found to be disseminated in Escherichia coli strains all over the world. It has a molecular weight of 4.0 megadalton and does not seem to be disadvantageous for the metabolism of the bacterial cell. The reason for the slow decrease of resistance to streptomycin and sulfonamide in clinical isolates, despite the restricted use of these drugs, is presumably the survival of bacteria harbouring pBP1 which have been selected by streptomycin and sulfonamides in the early days of chemotherapy.

Anti-Bacterial Agents↗
PubMed1981

Molecular nature of a streptomycin and sulfonamide resistance plasmid (pBP1) prevalent in clinical Escherichia coli strains and integration of an ampicillin resistance transposon (TnA).

A small, nonconjugative plasmid, designated pBP1, was originally found in different fecal Escherichia coli serotypes isolated from a healthy proband. Of a total number of 130 hospital strains of E. coli subsequently studied, 8.5% yielded plasmid of the pBP1 type. This R plasmid specifies resistance to streptomycin (Sm) and sulfonamides (Su) and has a mass of 4.0 megadaltons. Inactivation of streptomycin is due to the aminoglycoside phosphotransferase APH-(3 "). A physical map was constructed by analysis with restriction endonucleases. Another small plasmid, pBP1-1, was isolated from one of the hospital strains and characterized as an enlarged pBP1 replicon containing an additional deoxyribonucleic acid sequence identified as a transposable element for ampicillin resistance (TnA). Plasmid pBP1-1 was cleaved by restriction enzymes for identification of the transposon sequence which codes for a TEM 1 beta-lactamase. The sequence organizations in the Sm Su plasmids RSF1010 and pBP1 were shown to be identical for regions specifying streptomycin and sulfonamide resistance, but different for the region containing the origin of replication and genes for replicative functions. Thus, RSF1010, which has been considered as the prototype of Sm Su plasmids, and pBP1, which is at least as frequent in clinical isolates as RSF1010, do not have a single common ancestor.

Ampicillin↗
PubMed1979

[The propagation of aminoglycoside transferases in gram negative bacteria].

Molecular genetic and enzymatic studies on Gram-negative bacteria from hospital specimens give the following picture on surveillance of aminoglycoside transferases: The most frequent enzymes inactivate streptomycin only, AAD- (3'') and APH-(3''). Only 15% of the isolated enzymes inactivate gentamycin, tobramycin, sisomycin or amikacin. The most frequent of these are AAD-(2'') with 7% and AAC-(6') IV with 3%, both enzymes inactivate a wide range of substrates. The high frequency of streptomycin inactivating enzymes is due to the high incidence of linked resistance markers. A plasmid rPB1 is described, that is present in about 10% of all clinical isolates of E. coli. It has a molecular weight of 4. 1 Mdal and typical restriction pattern.

Aminoglycosides↗