PubMed Health⌕ Search

Biomedical subjects

H Claus

Publications and source records attributed to H Claus.

At least 19 recordsLinked to original sources
PubMed1997

Non-culture diagnosis and serogroup determination of meningococcal B and C infection by a sialyltransferase (siaD) PCR ELISA.

Rapid, non-culture, serogroup determination of meningococcal infection is important in contact management where vaccination may be possible. The impending availability of polysaccharide-protein conjugate vaccines for serogroup C disease requires maximal case ascertainment, with serogroup determination, at a time when the number of culture confirmed meningococcal infections is decreasing. A polymerase chain reaction assay (PCR), based on a restriction fragment length polymorphism (RFLP) in the meningococcal serogroup B and C sialytransferase (siaD) gene, was developed to combine the non-culture diagnosis of meningococcal infection from CSF, whole blood and serum with serogroup (B and C) identification. The PCR assay was adapted to an ELISA format incorporating hybridization with serogroup-specific B and C oligonucleotide probes. Specificity for CSFs was 100% and sensitivities were respectively 81, 63 and 30% for CSFs, whole blood and sera. The serogroup-specific PCR ELISA is a significant addition to currently available tests for non-culture diagnosis of meningococcal infection and outbreak investigation.

Base Sequence↗
PubMed1996

Discrimination of S. aureus strains by PCR for r-RNA gene spacer size polymorphism and comparison to SmaI macrorestriction patterns.

The size polymorphism of the internal spacer between the 16 S and the 23 S r-RNA genes was studied in S. aureus with the aid of PCR. The patterns of corresponding PCR products were compared with SmaI-generated macrorestriction patterns for definite propagating strains of S. aureus typing phages, for strains with phage pattern 29, phage-group II patterns, phage pattern 94, 96, phage pattern 95 and epidemic methicillin-resistant strains (MRSA). The spacer length polymorphism did not prove to be as discriminative as genomic DNA fragment patterns. However, as shown for S. aureus with phage patterns 29; group II; 94, 96; 95 and also for 4 out of 6 epidemic MRSA, unique patterns of r-RNA gene spacers probably indicate a relatedness among strains which is also suggested by SmaI macrorestriction patterns.

Base Sequence↗
PubMed1995

vanA-mediated high-level glycopeptide resistance in Enterococcus faecium from animal husbandry.

Glycopeptide-resistant Enterococcus faecium strains were isolated from a pig farm and a poultry farm both using avoparcin as a food additive. Such organisms were not isolated in a hen's eggs-producing farm not using avoparcin. Glycopeptide-resistant enterococci were also detected in broiler chicken carcasses that were delivered to a hospital's kitchen. The resistance was determined by the vanA gene as indicated by the detection of the inducible 39-kDa cytoplasmic membrane protein and of a vanA-specific DNA sequence amplified by polymerase chain reaction. Genomic DNA fragment patterns of strains from animal sources were different from each other and also from those of strains isolated in hospitals and from sewage treatment plants. This findings suggest the dissemination of the vanA determinant among different enterococcal strains of distinct ecological origin.

Animal Husbandry↗
PubMed1995

Enterococcus faecium strains with vanA-mediated high-level glycopeptide resistance isolated from animal foodstuffs and fecal samples of humans in the community.

The occurrence and the further spread of high-level glycopeptide-resistant, vanA-positive Enterococcus faecium strains outside of hospitals have been investigated. We could isolate such bacteria directly from thawing liquids of commercially produced frozen poultry (chickens, turkeys; no further data on previous feeding with avoparcin were available). In 5 of 13 samples of raw minced meat of pigs originating from 13 different butcher's shops, glycopeptide-resistant E. faecium (VanA type) could be detected after overnight broth cultivation of these samples. No glycopeptide-resistant enterococci could be isolated from meat samples of chickens that were fed without avoparcin. VanA type E. faecium strains were also identified in 12 fecal samples recovered from 100 nonhospitalized humans in the rural area of Saxony-Anhalt federal county. These results suggest a possible role of the food chain in the spread of glycopeptide-resistant E. faecium. Molecular typing (macrorestriction and multilocus enzyme analysis) reveal a wide dissemination of the vanA gene among strains of different ecological origins.

Animals↗
PubMed1995

[Epidemiological and microbiological studies on salmonellosis in Russia].

The occurrence of the most important Salmonella serovars in Russia from 1980 to 1993 is reported. Selected Salmonella strains isolated in Russia from 1951 to 1993 were characterized by serotype, phage type, resistance pattern, plasmid profile and detection of aerobactin production. The incidence of salmonellosis was different in the various administrative districts and varied between 0-235 cases/100,000 inhabitants. Since the middle of the eighties both the overall increase of salmonellosis and the replacement of S. typhimurium by S. enteritidis was also demonstrable in Russia. Nosocomial infections due to multiply resistant S. infantis strains and S. typhimurium strains which caused severe septicaemic courses in children were a special epidemic problem. These infections mainly occurred via faecal-oral transmission. In contrast ot Western Europe most of the S. enteritidis strains isolated in Russia belonged to phage type 1/1. Eight phage types were determined additionally. The S. typhimurium strains isolated in nosocomial infections belonged to a definite phage type and carried a 95 MDa plasmid. This plasmid was also detected in the nosocomial S. infantis strains, S. haifa strains, and S. panama strains. All these nosocomial strains formed aerobactin.

Anti-Bacterial Agents↗
PubMed1994

Characterization of two different clusters of clonally related methicillin-resistant Staphylococcus aureus strains by conventional and molecular typing.

The DNA fragments of 28 distinct isolates of methicillin-resistant Staphylococcus aureus (MRSA) originating from different hospitals in Warsaw and Lodz, were studied. They were obtained by cleavage with restriction endonuclease SmaI and subsequently analysed by pulsed-field electrophoresis. Sixteen different patterns were seen and clusters of related strains were clearly distinguishable. Minor differences in fragment patterns within these clusters and among epidemiologically related strains, revealed genomic rearrangements in the course of clonal dissemination of particular strains. The isolates were also checked for the expression of methicillin resistance. Isolates with heterogenous and homogeneous phenotypes, fell into clearly distinct clusters and thus formed two clonally related MRSA strains. Differences were also seen with phage and biochemical typing, and antimicrobial resistance patterns.

Bacterial Typing Techniques↗
PubMed1994

[Nosocomial infections with the detection of Staphylococcus aureus in an average hospital--an 11-year analysis].

Nosocomial infections over an 11 years period were monitored prospectively in a district hospital. A total of nosocomial infections among 162.197 patients discharged from 1980-1990 were analyzed. The incidence rate of nosocomial infections was 3.6%. The predominant isolates were Escherichia coli and Staphylococcus aureus (11%). The highest rates of S. aureus infections were established in wound infections and skin and mucosal infections at surgery, gynaecology and paediatrics departments. The number of multiply resistant S. aureus strains has decreased and those of sensitive isolates has increased. 72% of 652 S. aureus isolates have been typed by phage typing and biotyping. Statistical analysis could not establish a significant relationship between phage patterns and nosocomial infections. The spectrum of phage patterns of these nosocomial strains was the same as those of the endogenous colonization of men. Nosocomial outbreaks could not been realized.

Bacteriophage Typing↗
PubMed1993

Environmental strains of Enterococcus faecium with inducible high-level resistance to glycopeptides.

High-level resistance to glycopeptides in Enterococcus faecium is associated with an inducible 39-kDa cytoplasmic membrane protein. The present paper shows that such glycopeptide-resistant E. faecium strains can not only be isolated in a definite clinical setting but also from waste water of sewage treatment plants. Nearer characterization of these and of clinical isolates by resistance pattern, biotyping, and genotyping (DNA-fingerprinting with pulsed-field gel electrophoresis) has shown that different glycopeptide-resistant E. faecium strains have been isolated from clinical sources and from waste water.

DNA Fingerprinting↗
PubMed1993

Unrelatedness of multiply resistant Staphylococcus aureus with resistance to methicillin and to quinolones (QR-MRSA) as evident from SmaI-digestion patterns of genomic DNA.

Methicillin-resistant S. aureus with quinolone-resistance (QR-MRSA) isolated in Germany from three outbreaks of nosocomial infections and from sporadic nosocomial infections in five hospitals exhibited different SmaI-restriction patterns of their genomic DNA. Phage-typing and determination of plasmid profiles performed in parallel confirmed this differentiation, with one exception. These results indicate that there is obviously no overregional spread of one particular QR-MRSA clone and that quinolone resistance has developed independently in different MRSA.

Bacterial Typing Techniques↗
PubMed1993

[Clonal spreading of a multidrug resistance Citrobacter freundii strain at a neonatal intensive care unit].

This paper reports on the epidemic spreading of a multiresistant Citrobacter (C.) freundii strain at a neonatal intensive care unit. A premature baby of the 27th week of pregnancy died from septic shock caused by this strain. According to the result of a statistical analysis of risk factors a connection between the colonization of neonates and the feeding with an enteral feeding tube was probably. This suspicion could be confirmed by the detection of the multiresistant strain in the infant formula. Plasmid analysis, examination of outer membrane proteins and lipopolysaccharides of these C. freundii strains demonstrated the identity of all isolates. The resistance to antibiotics of this multiresistant C. freundii clone was determined by a plasmid belonging to incompatibility group C with a molecular weight of 110 MDa. This plasmid was involved also in other nosocomial outbreaks. It persisted more than 7 years in the hospital flora of the intensive care unit.

Anti-Bacterial Agents↗
PubMed1992

DNA fingerprints of Pseudomonas spp. using rotating field electrophoresis.

Rotating field electrophoresis (RFE) was applied to evaluate the usefulness of this technique for identification of several Pseudomonas strains with suspected importance in deliberate releases. Genomes of common wild-type or genetically modified strains of Pseudomonas fluorescens, Pseudomonas stutzeri, Pseudomonas putida and Pseudomonas aeruginosa were digested with rare-cutting restriction endonucleases and subjected to pulsed field gel electrophoresis. Restrictions with SpeI or XbaI produced 11-28 large DNA fragments in the range of 50-500 kb pairs. The specific genomic fingerprints were different for most strains of the same species, but identical for closely related strains. Differences were not affected by the presence of natural or genetically modified plasmids.

DNA Fingerprinting↗
PubMed1989

Hippocampal mossy fiber distribution and long-term potentiation in two inbred mouse strains.

We studied long-term potentiation in the inbred mouse strains DBA/2 and C3H/He known to be different in both hippocampal mossy fiber distribution and several aspects of learning. Tetanic stimulation of mossy fibers resulted in a significantly stronger increase of the population spike amplitude in the CA3 pyramidal cell layer of C3H mice. This result suggests that the extent of the CA3 hippocampal mossy fiber projection correlates with synaptic efficacy in mice.

Action Potentials↗