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H Meyer

Publications and source records attributed to H Meyer.

At least 91 records · Page 5Linked to original sources
PubMed2000

A miniaturised semiautomated system for the identification of Yersinia species within the genus Yersinia.

Commercially available identification systems based on biochemical reactions of bacteria are not suited for typing the species of the genus Yersinia (Y.) or the biovars (BV) of the species Y. enterocolitica. This failure is caused by the limited number of biochemical reactions applied, resulting in the absence of important discriminatory key reactions. The MICRONAUT identification system (Merlin, Bornheim-Hersel) makes use of dried substrates/enzymes reactions in the wells of a 96-well microtitration plate, reading of the results by a scanner device and typing of the isolate by the calculation of probabilities according to a data base. For this study a special identification panel was designed on which 38 substrates and enzyme reactions were configurated including 20 reactions for the identification of the species of the genus and the Y. enterocolitica biovars. The database was calculated using the results obtained from a total of 250 Yersinia strains of the eleven species of the genus. Reevaluation of the results of these strains revealed an overall sensitivity of 98%, as only four strains were not identified satisfactorily. Considering also questionable results the sensitivity was still 85%. The system was also used to identify Y. pestis isolates, but in this case reading was done visually. The printouts usually cite species designation, identification quality and probabilities. The sealing of the plates in an aluminium bag guarantees long life and long lasting quality. However, an evaluation of the system with a considerable number of strains has to be done in a next step. The 'Yersinia identification set' can replace time-consuming tube testing in the future and is a big step forward towards a sensitive identification of Yersinia isolates in the routine laboratory.

Automation↗
PubMed2000

Specific detection of plasmid bearing Yersinia isolates by PCR.

A total of 210 isolates belonging to 9 different species of the genus Yersinia (Y.) was investigated with three different PCR assays targeting two plasmoidal genes, the Yersinia adhesin gene (yadA) and the V-antigen gene. The yadA PCR assay described in 1995 by Blais and Phillipe, targeting a Y. enterocolitica specific gene region and a newly designed assay targeting the gene region functionally responsible for autoagglutination, were compared. Both assays identified the same Y. enterocolitica strains. To exclude the possibility that false negative results were obtained due to mutations that had occurred in parallel in both gene regions, a third PCR assay by Neubauer et al. (2000) targeting a conserved region of the V-antigen gene was used as control. Again, DNA of the same Y. enterocolitica strains was amplified. In contrast to the yadA PCR assay described by Blais and Phillipe, the newly established yadA and the V-antigen PCR assays amplified DNA from Y. pseudotuberculosis strains. Therefore, by using the PCR technique as a molecular tool spontaneous mutations could be excluded as the cause of anomalous reactions in PCR assays targeting genes of the Yersinia virulence plasmid. Based on these results, it can be assumed that all presumptive pathogenic Yersinia isolates can be identified on the basis of PCR analysis. These molecular assays may also produce fewer false positive reactions in comparison to phenotypic tests such as the autoagglutination test which depend heavily on the handler's experience. It has to be stressed that the PCR assays used in this study have not been evaluated for routine use. Therefore, standardization of the PCR methodology including sample preparation, primer target sequences and PCR reagents is needed for the reliable and safe diagnosis of pathogenic Yersinia spp. in future.

Adhesins, Bacterial↗
PubMed2000

[Detection of the genome of bovine viral diarrhea virus (BVDV) using the polymerase chain reaction after reverse transcription (RT-PCR): comparison of methods for the isolation of ribonucleic acid (RNA) from clinical samples].

The RT-PCR is an in vitro technique that is increasingly being used for diagnosis of viral animal pathogens. Due to its high sensitivity it is considered as an alternative to current standard methods for detecting BVDV especially in pooled samples, e.g. from bulk tank milk. A prerequisite for the performance of RT-PCR is an efficient and simple method for sample preparation. The aim of this work was to compare the efficiency of three commercially available kits for RNA extraction, and their suitability for sample preparation for the detection of the BVDV genome by RT-PCR in blood, milk and tissue samples. The kits were based on different methods for extraction of RNA and differed in costs, labour and time consumption. The most sensitive RT-PCRs (exception: heparinised blood) were obtained when sample preparation was performed by acidic guanidinium-isothiocyanate-phenol-chloroform extraction with the Trizol (Gibco) reagent. Using a kit based on the binding of RNA to silica membrane in a spin column, positive results in RT-PCR were obtained from all samples, but with lower sensitivity. The advantage of the column-based kits is that they are less time-consuming, easier to handle and suitable for automatisation of sample preparation. A kit using salt precipitation of the desoxribose nucleic acid (DNA) and proteins was unsuitable for the isolation of viral RNA from the samples.

Animals↗
PubMed1999

Structural characterization of lichenysin A components by fast atom bombardment tandem mass spectrometry.

The structural characterization of the cyclic lipoheptapeptide surfactant lichenysin A components, produced by Bacillus licheniformis strains via the non-ribosomal pathway on a corresponding peptide synthetase, was carried out using a tandem mass spectrometry (MS/MS) under fast atom bombardment (FAB) conditions. Based on the analysis of the collision-induced fragment-ion spectrum of the single charged molecular ions of both native and partially hydrolyzed forms of lipopeptide, a new general structure of lichenysin A components was elucidated. It varies from previously proposed structure by having in the peptide portion of lipopeptide the L-Gln-1 and L-Asp-5 residues instead of L-Glu-1 and L-Asn-5. The verified chemical structure of lichenysin A was found to be reflected in the structural organization of the corresponding lichenysin A synthetase, LchA, described recently.

Bacillus↗
PubMed1999

Equine glanders in Turkey.

In the course of an epidemiological study of glanders on a number of Turkish islands in the Sea of Marmara, 1128 horses were examined by using the intracutaneous mallein test. Thirty-five (3-1 per cent) developed an increase in rectal temperature and a swelling at the point of injection. Ten of these horses were killed and glanders was confirmed in five cases by the presence of lesions and by the immunohistological demonstration of the causative agent, Burkholderia mallei. Clinical and pathological findings indicated that in all cases the infection was restricted to the mucous membrane of the nasal cavity with its parasinus, the nostrils and the upper lips. It was confirmed that equine glanders is endemic in Turkey.

Animals↗
PubMed1999

Characterization of orthopoxviruses isolated from man and animals in Germany.

Fourteen orthopoxvirus strains isolated from humans, cats, a dog, a cow, and an elephant in Germany were characterized. All were classified as cowpox virus based on haemorrhagic lesions induced on the chorioallantoic membrane of chicken eggs and reactivity of a 160 kDa protein with anti-A-type inclusion protein hyperimmune serum in a Western blot. More detailed comparison of the isolates by restriction endonuclease mapping using HindIII and XhoI demonstrated a close relationship between all isolates and confirmed them as cowpox viruses. However, some minor differences between the isolates were detected which proved to be of epidemiological value. One group consisting of five closely related isolates contained a unique 4.0 kb HindIII fragment. In a Southern blot this fragment failed to hybridize with other cowpox virus isolates including the reference strain.

Amino Acid Sequence↗
PubMed1999

Auditory stimuli as a trigger for arrhythmic events differentiate HERG-related (LQTS2) patients from KVLQT1-related patients (LQTS1).

OBJECTIVE: This study was performed to identify a possible relationship between genotype and phenotype in the congenital familial long QT syndrome (cLQTS). BACKGROUND: The cLQTS, which occurs as an autosomal dominant or recessive trait, is characterized by QT-interval prolongation on the electrocardiogram and torsade de pointes arrhythmias, which may give rise to recurrent syncope or sudden cardiac death. Precipitators for cardiac events are exercise or emotion and occasionally acoustic stimuli. METHODS: The trigger for cardiac events (syncope, documented cardiac arrhythmias, sudden cardiac death) was analyzed in 11 families with a familial LQTS and a determined genotype. RESULTS: The families were subdivided in KVLQT1-related families (LQTS1, n = 5) and HERG (human ether-a-gogo-related gene)-related families (LQTS2, n = 6) based on single-strand conformation polymorphism analysis and sequencing. Whereas exercise-related cardiac events dominate the clinical picture of LQTS1 patients, auditory stimuli as a trigger for arrhythmic events were only seen in LQTS2 patients. CONCLUSIONS: Arrhythmic events triggered by auditory stimuli may differentiate LQTS2 from LQTS1 patients.

Acoustic Stimulation↗
PubMed1999

Variations in the 16S rRNA gene sequence of Yersinia enterocolitica isolates influence the specificity of molecular identification systems.

Four identification systems were used to type Yersinia enterocolitica strain Y11 and Yersinia enterocolitica sensu strictoT. Two systems based on biochemical reaction patterns identified both strains as Yersinia enterocolitica. Two molecular assays targeting the 16S rRNA gene failed to identify either strain Y11 or the type strain. Therefore, both strains were typed by the classical taxonomical approach requiring a determination of the overall base composition and the base sequence similarity using hybridization. Again both strains were classified as Yersinia enterocolitica isolates. Consequently, the sequences of the 16S rRNA gene of both strains were determined and compared. The strains differed in a region where nucleotide changes between species of the genus Yersinia had been described earlier. These differences may explain the failure of the molecular assays to identify the strains. They also demonstrate an independent evolution of the 16S rRNA genes in the species Yersinia enterocolitica sensu stricto suggesting an amendment to the nomenclature to be used in the future.

DNA, Ribosomal↗
PubMed1999

Results after Norwood procedure and subsequent cavopulmonary anastomoses for typical hypoplastic left heart syndrome and similar complex cardiovascular malformations.

OBJECTIVE: From October 1989 to June 1998, 60 patients have undergone the Norwood procedure (stage I) at our institution. The results of the staged surgical reconstruction and risk factors were analysed. Typical hypoplastic left heart syndrome (HLHS) and complex lesions with aortic hypoplasia were compared with each other. PATIENTS: Typical HLHS: N = 48, median age 15 days (5-190 days), median weight 3.6 kg (2.6-5.3 kg). Complex lesions (dominant left ventricle): N = 12, median age 59 days (10-884 days), median weight 3.4 kg (2.4-12 kg). RESULTS: Typical HLHS: The stage-I hospital survival was 73% (35/48). It improved from 60% (95% confidence interval: 49-71%) during 1989-1994 to 91% (95% CI: 81-100%) during 1997-1998. Seven patients were lost late. The right ventricular end diastolic diameter (P = 0.015), shortening fraction (P = 0.027), and the presence of an obstructed pulmonary venous return (P = 0.0032) were significant risk factors. 23 children underwent stage-II operation with four (17%) deaths. All survivors experienced an improvement of their statomotoric development. Stage-III operation was performed in 13 patients with no hospital death. Follow up after stage-III procedure was 7 months to 7 years. 4 year actuarial survival, including hospital mortality and deaths at subsequent stages, improved from 28% (95% CI: 18-38%) during 1989-1994 to 58% (95% CI: 48-68%) during 1994-1997. No patient had signs of myocardial insufficiency. Complex lesions: Stage-I hospital survival was 83% (10/12) with no late death. Stage-II was performed in 8 and stage-III in 6 patients with no death respectively. CONCLUSION: In typical HLHS the results have improved over time. Both size and function of the right ventricle determined significantly stage-I survival. An early operation prevents the natural progression of pulmonary blood flow and may weaken all three risk factors. Patients with complex lesions seemed to have better chances of surviving the early postoperative period. The multistage reconstructions have become a realistic option for patients with HLHS and similar lesions, regardless of the morphologic subtype or diminutiveness of the aorta, and lead to an acceptable quality of life.

Abnormalities, Multiple↗
PubMed1999

Cowpox: reservoir hosts and geographic range.

It is generally accepted that the reservoir hosts of cowpox virus are wild rodents, although direct evidence for this is lacking for much of the virus's geographic range. Here, through a combination of serology and PCR, we demonstrate conclusively that the main hosts in Great Britain are bank voles, wood mice and short-tailed field voles. However, we also suggest that wood mice may not be able to maintain infection alone, explaining the absence of cowpox from Ireland where voles are generally not found. Infection in wild rodents varies seasonally, and this variation probably underlies the marked seasonal incidence of infection in accidental hosts such as humans and domestic cats.

Animals↗
PubMed1999

Digestibility and compatibility of mixed diets and faecal consistency in different breeds of dog.

The digestive capacity of dogs varying in body size was tested. Digestive experiments were conducted with 10 different canine breeds (n = 66) with body weights ranging from 4.2 to 52.5 kg with 4-9 individuals. The animals were fed a canned or a dry commercial diet with a constant dry matter intake of 13 g/kg BW/day, except in Irish wolfhounds, which ingested only 10 g dry matter with the canned diet. Faecal dry matter was around 14% (absolutely) higher for the dry diet compared to the canned food, with a tendency in the larger breeds towards higher faecal water contents, less favourable faecal quality and increased numbers of defaecations. The Irish wolfhounds, the largest breed tested, had faeces with considerably lower water contents compared to Labrador retrievers, indicating that body weight is not the only factor to be considered. There were only small differences in the apparent digestibility of crude nutrients amongst the breeds. Sodium and potassium absorption was higher when the dry diet was fed compared to the canned food. In conclusion, breed and individual factors have to be taken into account when performing tests with dog food. Test panels for evaluating commercial diets should include breeds of larger body size and higher sensitivity to dietary disorders.

Animal Feed↗
PubMed1999

Posttraumatic stress disorder symptoms related to psychosis and acute involuntary hospitalization in schizophrenic and delusional patients.

The aims of this study were: a) to assess the prevalence of posttraumatic stress disorder (PTSD) after an acute psychotic episode in schizophrenic and delusional patients, b) to explore which psychotic symptoms and aspects of treatment were associated with traumatization, and c) to compare the extent of the traumatic impact of psychosis and involuntary hospitalization. Forty-six schizophrenic and delusional patients were assessed with the Positive and Negative Syndrome Scale (PANSS), the Impact of Event Scale-Revised (IES-R), and the Clinician-Administered PTSD Scale (CAPS) at weeks 1 and 8 after acute psychiatric admission. Traumatic symptoms related to psychosis and coercive measures were scored separately. The prevalence of PTSD was found to be 11%. Sixty-nine percent of traumatic symptoms were related to psychosis and 24% to hospitalization. High PANSS score at week 8 was the strongest risk factor for the development of PTSD. Particularly positive and depressive/anxious symptomatology were associated with psychosis-related traumatic symptoms at both weeks 1 and 8. These data suggest that, in general, schizophrenic and delusional symptoms are more traumatic than the coercive measures used to control them.

Adult↗
PubMed1999

Phylogeny and polyphasic taxonomy of Caulobacter species. Proposal of Maricaulis gen. nov. with Maricaulis maris (Poindexter) comb. nov. as the type species, and emended description of the genera Brevundimonas and Caulobacter.

The genus Caulobacter is composed of prosthecate bacteria often specialized for oligotrophic environments. The taxonomy of Caulobacter has relied primarily upon morphological criteria: a strain that visually appeared to be a member of the Caulobacter has generally been called one without challenge. A polyphasic approach, comprising 16S rDNA sequencing, profiling restriction fragments of 16S-23S rDNA interspacer regions, lipid analysis, immunological profiling and salt tolerance characterizations, was used to clarify the taxonomy of 76 strains of the genera Caulobacter. Brevundimonas, Hyphomonas and Mycoplana. The described species of the genus Caulobacter formed a paraphyletic group with Caulobacter henricii, Caulobacter fusiformis, Caulobacter vibrioides and Mycoplana segnis (Caulobacter segnis comb. nov.) belonging to Caulobacter sensu stricto. Caulobacter bacteroides (Brevundimonas bacteroides comb. nov.), C. henricii subsp. aurantiacus (Brevundimonas aurantiaca comb. nov.), Caulobacter intermedius (Brevundimonas intermedia comb. nov.), Caulobacter subvibrioides (Brevundimonas subvibrioides comb. nov.), C. subvibrioides subsp. albus (Brevundimonas alba comb. nov.), Caulobacter variabilis (Brevundimonas variabilis comb. nov.) and Mycoplana bullata belong to the genus Brevundimonas. The halophilic species Caulobacter maris and Caulobacter halobacteroides are different from these two genera and form the genus Maricaulis gen. nov. with Maricaulis maris as the type species. Caulobacter leidyia was observed to cluster with species of the genus Sphingomonas. Caulobacter crescentus is synonymous with C. vibrioides and C. halobacteroides is synonymous with Maricaulis maris as determined by these analyses and DNA-DNA hybridization. Biomarkers discerning these different genera were determined. The necessary recombinations have been proposed and a description of Maricaulis is presented.

Antigens, Bacterial↗
PubMed1999

Identification of Yersinia species by the Vitek GNI card.

The Vitek GNI card was used to identify 212 isolates of 10 Yersinia species. Identification was correct for 96.3% of the isolates (156 of 162) to the genus level and for 57.4% of the isolates (93 of 162) to the species level for Yersinia spp. listed in the Vitek database. We recommend additional identification methods for isolates assigned to the genus Yersinia by the Vitek system.

Bacteriological Techniques↗
PubMed1999

Wish lists: 1999 lobbying outlook.

It's an uncertain year for Congress, but the health agenda is already filling in with both big-picture and nitty-gritty concerns. From patient protection to patents, health care's top advocacy groups describe what they want most from Washington. As the legislative season gets under way, here's what they'll lobby for.

American Hospital Association↗
PubMed1999

[Animals as sources of infections in humans--salmonellosis].

Foodborne infections/intoxications of men including salmonelloses increased as a whole in the last years. Some reasons for this development are discussed. From the 2,500 Salmonella serovars known at present only 10 to 15 are of epidemic importance, in the first place S. Typhimurium and S. Enteritidis. Mainly salmonella-contaminated foodstuffs from animals are sources of Salmonella infections in men. In this connection raw eggs and raw egg-containing food, as well as raw meat and meat products are of prime importance. Especially endangered are humans whose mechanisms of infectious defence are not fully developed (infants, young children) or are impaired to some extent (elderly people, immunocompromised persons). Salmonellosis control has to be carried out as a concerted action along the whole food chain, starting at animal farms and continuing with adequate methods at each stage of food production and processing, in trade, in restaurants and canteens up to private households. In connection with the health protection of consumers hygienic education of staff handling foodstuffs, as well as information of consumers are very important. Despite some deficiencies our knowledge is sufficient to work effectively in practice to improve the situation.

Animals↗
PubMed1999

[Cowpox viruses in Germany: an analysis of 5 cases in 1998].

Five case reports on cowpox virus infections in cats, humans, and for the first time in a horse are presented. It becomes obvious that in most cases the diagnosis cowpox is suspected rather late, although fast and reliable diagnostic tools such as pathohistological examination and polymerase chain reaction are available. The threat of a zoonotic transmission mainly through cats is gaining importance. Although wild rodents have been claimed to be the reservoir and source for cowpox viruses in cats, very little is known about the epidemiology of cowpox virus. Based on the different genome organizations found in the German isolates, we conclude that various subtypes of cowpox virus are circulating in Germany at one time.

Animals↗