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H Rinder

Publications and source records attributed to H Rinder.

At least 37 records · Page 2Linked to original sources
PubMed1999

Genetic differentiation of mites of the genus Chorioptes (Acari: Psoroptidae).

In an effort to clarify the species status of mites of the genus Chorioptes the second internal transcribed spacer of the rRNA gene was characterized in 14 isolates from cattle, horse, sheep and llama of different geographic origins. The genotypes segregated into two clearly separated groups of DNA sequences. In addition, two phenotypes could be distinguished by the lengths of the outer opisthosomal setae of male adults which had previously been designated as Chorioptes bovis and Chorioptes texanus. The bipartite division of genotypes and phenotypes correlated completely in all isolates. Nine out of ten cattle isolates from three continents were determined to be C. texanus including the first description in Europe and Northern America. Chorioptes texanus appears to have a wider geographic distribution than previously known. Chorioptes bovis was found in four different host species. The apparent lack of host specificity of both species implicates a potential that mites are dispersed freely in a wide range of hosts and this might have contributed to the wide geographic distribution of these species.

Acari↗
PubMed1999

Effect of recombinant human megakaryocyte growth and development factor coupled with polyethylene glycol on the platelet storage lesion.

BACKGROUND: Platelet production is regulated by a thrombopoietic growth factor (Mpl ligand). The receptor for this platelet growth factor (Mpl) is expressed on the platelet surface membrane. A recombinant thrombopoietic cytokine, recombinant human megakaryocyte growth and development factor coupled with polyethylene glycol (PEG-rHuMGDF), was added to apheresis platelets in vitro to determine whether Mpl ligand-receptor binding produced any beneficial or adverse effect on the development of the platelet storage lesion during 5 days of storage. STUDY DESIGN AND METHODS: This study was designed as a dose-response protocol to determine the effects of adding increasing concentrations of PEG-rHuMGDF (0.0 [control], 2.5, 25, and 250 ng/mL) to apheresis platelets stored in two types of plastic storage containers. The increasing concentrations of PEG-rHuMGDF used simulated the theoretical peak plasma level attained in vivo, with an intravenous dose of 0, 0.1, 1.0 and 10 microg per kg of PEG-rHuMGDF. The platelets were stored with agitation at 20 to 24 degrees C for 5 days. A battery of in vitro assays was performed on storage Days 1 and 5, including pH, blood gases, platelet count, lactate dehydrogenase, mean platelet volume, glucose, lactate, osmotic recovery, morphology score, CD62P, and one-dimensional polyacrylamide gel electrophoresis analyses. RESULTS: Analysis of results on both Day 1 and Day 5 showed no significant differences among any of the three PEG-rHuMGDF doses and the control group, for any in vitro assay. One-dimensional polyacrylamide gel electrophoresis showed no changes among the platelet protein patterns for the three PEG-rHuMGDF doses studied or the control. Storage-induced changes, however, did occur equally in all four groups of platelets over the 5 days of storage. CONCLUSION: The addition to stored apheresis platelets of up to 10 microg per kg of PEG-rHuMGDF (250 ng/mL), followed by 5 days of storage at standard conditions, does not appear to promote or retard development of the platelet storage lesion.

Blood Glucose↗
PubMed1998

Significance of ahpC promoter mutations for the prediction of isoniazid resistance in Mycobacterium tuberculosis.

To determine the value of ahpC promoter mutations for the rapid prediction of isoniazid resistance, this genomic region was characterized in 50 isoniazid-resistant and 12 isoniazid-sensitive Mycobacterium tuberculosis isolates. Of the resistant isolates, 12 had ahpC promoter mutations, but only one possessed both an ahpC promoter mutation and a katG codon 315 substitution, although the latter was found in the majority (54%) of the isoniazid-resistant isolates investigated. This investigation presents empirical evidence that the central portion of the ahpC promoter is the most valuable genetic locus to complement katG codon 315 characterizations in order to increase the sensitivity of molecular tests for the prediction of isoniazid resistance.

Antitubercular Agents↗
PubMed1998

Characteristic genotypes discriminate between Babesia canis isolates of differing vector specificity and pathogenicity to dogs.

The first and second internal transcribed spacers (ITS1, ITS2) as well as the intervening 5.8S coding region of the rRNA gene were characterized in eight Babesia canis isolates of differing geographic origin, vector specificity, and pathogenicity to dogs. The genotypes determined by sequencing segregated into three clearly separated groups close to or near the species level and correspond to the previously proposed subspecies B. canis canis, B. canis vogeli, and B. canis rossi. The three genotypes can be distinguished by Sau96I digestion of the polymerase chain reaction (PCR)-amplified rDNA target.

Animals↗
PubMed1998

Genetic evidence suggests that Psoroptes isolates of different phenotypes, hosts and geographic origins are conspecific.

The second internal transcribed spacer of the rRNA gene was characterised in 15 Psoroptes isolates collected from the ears or bodies of rabbits, goats, sheep and cattle originating from four continents. Morphologically, the isolates were differentiated as Psoroptes cuniculi, Psoroptes ovis and Psoroptes cervinus. Genotypically, the isolates were highly homogeneous, except for the existence of different rDNA classes. In view of previous phenotypic data, a possible conspecificity of these species is proposed.

Animals↗
PubMed1998

Blinded, externally controlled multicenter evaluation of light microscopy and PCR for detection of microsporidia in stool specimens. The Diagnostic Multicenter Study Group on Microsporidia.

The quality parameters for the detection of microsporidia in identical sets of 50 stool samples were determined for six laboratories where technicians used light microscopy and for six laboratories where technicians used PCR. The average overall sensitivities were 67% (89% for patient samples only) for the PCR laboratories and 54% (80% for patient samples only) for the light microscopy laboratories. Specificities were 98 and 95%, respectively. Differences in results were most apparent between the individual laboratories rather than between the two major methods used.

Animals↗
PubMed1998

Strain differentiation in microsporidia.

Microsporidia are obligate intracellular, spore-forming protozoa and are regarded as newly emerging pathogens . Enterocytozoon spp. as well as Encephalitozoon spp. are recognized as major aetiological agents in chronic diarrhoea of immnunocompromised patients. The detection and differentiation of strains within microsporidial species is a prerequisite for the elucidation of their hitherto unknown reservoirs and their mode of transmission . In Enterocytozoon bieneusi, the most prevalent human-pathogenic microsporidium, 6 different genotypes of the internal transcribed spacer (ITS) of the rRNA gene are known so far, with 12 polymorphic sites . This pathogen has infrequently been detected in 2 animal hosts only, pigs and rhesus macaques, and only the genotype of the latter has also been found in a human patient, too. Encephalitozoon cuniculi has a wider confirmed spectrum of animal hosts, but only one polymorphic site is known in the ITS, differing in 3 different numbers of a tetranucleotide repeat. Therefore, further genomic targets may have to be characterized, too. Few data are available on strain differentiation in Encephalitozoon intestinalis and E. hellem.

Animals↗
PubMed1997

Geographic variation of the predictive values of genomic mutations associated with streptomycin resistance in Mycobacterium tuberculosis.

Specific mutations associated with resistance to streptomycin (SM) in Mycobacterium tuberculosis suggest themselves for its rapid prediction. However, as with any diagnostic test, their predictive values are dependent on their prevalences. In this report, SM resistance associated mutations in the rrs and rpsL genes of 25 SM resistant isolates from Germany and 25 SM resistant isolates from Sierra Leone were characterized and compared. Mutations in the rrs gene were infrequent in isolates from both localities (20% and 12%, respectively) and thus of limited predictive values. In contrast, rpsL mutations were found in 48% of the German isolates but only in 24% of the isolates from Sierra Leone. It is concluded that the predictive values of mutations in this gene may vary significantly with the origin of the samples under investigation.

Antibiotics, Antitubercular↗
PubMed1997

Comparison of polymerase chain reaction with light microscopy for detection of microsporidia in clinical specimens.

The detection of microsporidial DNA by the polymerase chain reaction (PCR) has been suggested as an alternative or supplement to conventional microscopic methods. However, the relative merits of these techniques remain uncertain. In the present study, clinical specimens of different origin (stool, urine, sputum, nasal discharge, and cerebrospinal fluid) containing four different microsporidial species were blinded after microscopic examination and analyzed by PCR and subsequent restriction fragment length polymorphism (RFLP) to determine the respective species. Thirty-four specimens from 31 patients were evaluated, 16 of which were positive and 18 negative by microscopic examination; PCR detection of microsporidia produced identical results in 82% (28/34) of these specimens. Four samples were microscopically negative, PCR-positive, and two were microscopically positive, PCR-negative. Species determination by RFLP analysis of the amplified product was accurate for all isolates containing Enterocytozoon bieneusi, Encephalitozoon intestinalis, Encephalitozoon hellem, and Encephalitozoon cuniculi compared with microscopic identification of the genus Enterocytozoon or molecular analysis of Encephalitozoon species after in vitro culture. Therefore, PCR-RFLP is useful for the rapid detection and differentiation of microsporidian spores in clinical specimens.

Animals↗
PubMed1997

Evidence for the existence of genetically distinct strains of Enterocytozoon bieneusi.

Enterocytozoon bieneusi is the most frequently found microsporidium in human infections. In all, 3 distinct genotypes were detected in 12 stool samples from 8 patients with acquired immunodeficiency syndrome (AIDS). A total of 9 polymorphic sites were found in the 243-bp-long internal transcribed spacer (ITS) of the rDNA gene, whereas none was found in 241 bp of adjacent rRNA coding regions. The genotype was stable in samples taken during 11 weeks of infection from one of the patients. The existence of and the ability to discriminate among strains of E. bieneusi are important prerequisites for elucidation of the hitherto unknown reservoirs of this pathogen and the mode of its transmission and may explain its pathogenicity.

AIDS-Related Opportunistic Infections↗
PubMed1997

Disequilibria in the distribution of rpoB alleles in rifampicin-resistant M. tuberculosis isolates from Germany and Sierra Leone.

The effectiveness of culture-independent resistance predictions by molecular techniques is dependent on the number and the frequency of accessible resistance-associated genomic mutations. We have characterized an rpoB gene region involved in rifampicin resistance in 49 Mycobacterium tuberculosis isolates resistant to rifampicin from Germany and Sierra Leone. The determined frequencies of mutations differed between both countries of origins as well as with respect to previously reported distributions of resistance mutations. It is concluded that at least for some isolates the acquisition of mutations leading to rifampicin resistance in clinical samples of M. tuberculosis is a non-random process which may lead to a geographical and temporal dependence of the sensitivities of molecular typing techniques for rifampicin resistance predictions.

Alleles↗
PubMed1997

Relationships between species of the Rhipicephalus sanguineus group: a molecular approach.

The biosystematic status of species belonging to the Rhipicephalus sanguineus group is difficult to determine by phenotypic methods and has been subject to frequent revisions and ongoing debate. Yet, the differentiation of species within this complex is of clinical importance especially in veterinary medicine due to different host specificities of the transmitted pathogens. In order to generate quantifiable and comparable data independent of environmental influences, a section of the second internal transcribed spacer (ITS2) of the rRNA gene was sequenced for 6 species belonging to the Rhipicephalus sanguineus complex: Rhipicephalus sanguineus sensu stricto, R. turanicus, R. rossicus, R. pumilio, R. pusillus, and R. camicasi. Rhipicephalus sanguineus s. str. and R. turanicus as well as R. pumilio and R. rossicus were found to have a close genetic relationship compatible with possible conspecificities. Conversely, R. pusillus was found to have the most distant relationship to the other species.

Animals↗
PubMed1997

Limited range of genetic variation in Echinococcus multilocularis.

DNA sequencing of 1.3 kb of rDNA containing both internal transcribed spacers (ITS1, ITS2) and adjoining rRNA coding regions in each of 11 Echinococcus multilocularis isolates from Germany, Japan, and Alaska resulted in identical nucleotide sequences except for a single polymorphic locus 54 bp upstream of the 3' end of the 18S coding region, separating Eurasian isolates from an Alaskan isolate. The same base substitution was found in each of 2 additional isolates from Alaska. The distribution of the resulting genotypes with regard to their origin is highly significant (>99.9%) and corresponds to the traditional subspecies Echinococcus multilocularis multilocularis and Echinococcus multilocularis sibiricensis.

Animals↗
PubMed1997

Usefulness of Mycobacterium tuberculosis genomic mutations in the genes katG and inhA for the prediction of isoniazid resistance.

SETTING: Mutations in two genes of Mycobacterium tuberculosis, inhA and katG, are known to correlate with resistance to isoniazid (INH). OBJECTIVE: To determine which mutation or mutations are the most predictive for INH resistance and the most frequent ones in such isolates. Further, to propose a simple and generally applicable method for their detection. DESIGN: Codons 94 and 95 in the inhA gene and codons 315 and 463 in the katG gene were characterized in 50 INH-resistant and 12 INH-sensitive isolates from Germany and Sierra Leone. RESULTS: Mutations in codon 315 of the katG gene were detected in 27 of the INH-resistant and none of the INH-sensitive isolates. All mutations in this codon altered an AciI restriction enzyme site. No mutations were found in the investigated codons of the inhA gene. CONCLUSION: We propose that most INH resistances can be rapidly predicted by a simple AciI restriction enzyme digest of a polymerase chain reaction (PCR)-amplified katG fragment.

Antitubercular Agents↗
PubMed1996

Direct amplification and species determination of microsporidian DNA from stool specimens.

Microsporidia are recognized as a major aetiological agent in chronic diarrhoea of immunocompromised patients. Their detection by light microscopy is hampered by the small size of the spores. A simple and rapid DNA extraction method has been developed for the detection of microsporidian DNA by PCR directly from stool specimens. It can be performed at room temperature in a 1.5-ml microcentrifuge tube format in less than 1 hour. The subsequent nested polymerase chain reaction permits the detection of 3-100 spores in a 0.1-g stool sample. The amplification products can be verified and the species Enterocytozoon bieneusi, Encephalitozoon cuniculi and Encephalitozoon (Septata) intestinalis distinguished by a simple restriction endonuclease digest.

Animals↗
PubMed1996

Rapid identification of mycobacterial species by PCR amplification of hypervariable 16S rRNA gene promoter region.

A total of 0.3 to 0.4 kb of the promoter region of the 16S rRNA genes from Mycobacterium tuberculosis, M. gordonae, M. xenopi, and M. leprae was PCR amplified, cloned, and sequenced. The observed number of substitutions, insertions, and deletions exceeded those found in previously used target sequences, including the entire 16S coding region. A simple and generally applicable restriction fragment length polymorphism method that can be used to distinguish between mycobacterial species is described.

Base Sequence↗
PubMed1996

[Dermacentor ticks in France and Germany. Molecular biological differences in species, ecology and epidemiological implications].

Dermacentor reticulatus and D. marginatus, two ixodid tick species occurring in France and Germany, exhibit morphologically overlapping phenotypes. The results of sequence analyses of the hypervariable rDNA gene region ITS 2 do not support conspecifidity. As in France, D. reticulatus has to be characterized as an epidemiologically effective vector of Babesia canis in Germany as well, with the endemic area being located at Kehl/Offenburg/Lahr/Emmendingen/Freiburg in Breisgau. Ecological investigations indicate that a spreading of D. reticulatus and, as a possible consequence, that of B. canis in Germany has to be expected.

Animals↗