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B Herrmann

Publications and source records attributed to B Herrmann.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Reproducibility of aDNA typing].

The reproducibility of short tandem repeat (STR) amplification of aDNA extracts is limited by means of formation of artifacts during PCR. One of these artifacts, the so called allelic-dropout (failure of the amplification of alleles), may result in false-homozygote typing of a sample, if genotyping is based on the analysis of a single amplification product. 30 tooth- and bone samples collected from 17 individuals of three burial sites were investigated in a blind test. Using the polymerase chain reaction (PCR) the two independent segregating STR-loci HUMVWA and HUMTH01 were amplified. Corresponding to a mathematical estimation, multiple amplifications of each sample and genelocus were carried out. The results of this genotyping were compared intraindividually.

Bone and Bones↗
PubMed1997

[Classification of isolated skeletal elements using aDNA typing].

Analysis of ancient DNA of material found in the Lichtensteinhöhle, a burial site of the Younger Bronze Age has been used for the first time to assign isolated skeletal elements to corresponding individuals. The method involved DNA typing through amplification of five Short Tandem Repeat loci which are also used in forensic genetics for the determination of kinship and identification. From all of the examined bone samples DNA was successfully extracted and amplification by means of Polymerase Chain Reaction could be carried out. For the skeletal elements allelic profiles which are specific for an individual were set up. These profiles made it possible to recognize bones belonging to one individual. Elements which were not from this individual could be excluded with certainty by aDNA analysis.

Bone and Bones↗
PubMed1997

[Determination of kinship by aDNA analysis].

Molecular sex determination and aDNA typings were carried out on a group of five prehistoric individuals. Due to the burial situation and the individual ages the group was assumed to be a family consisting of the parents and three children. DNA was extracted from teeth and bone samples of all skeletons. The aDNA typings based on the PCR amplification of four different microsatellite DNA loci, so-called human short tandem repeats (STR). Results of the molecular sex determinations and allele determinations are presented and compared with morphological determinations. Up to now, the individual biological kinship could be verified for three of the individuals. This is the first proof of individual biological kinship on the molecular level for prehistoric individuals.

Adult↗
PubMed1997

[Prospects in prehistoric anthropology?].

Although Prehistoric Anthropology seems to flourish there are reasons for concern. Innovative developments as e.g. molecular techniques require rethinking of concepts and more staff and money, requirements for which Prehistoric Anthropology seems not to be well prepared to cope with. One way to drive back competition by foreign subjects could be to set up research co-operation.

Anthropology↗
PubMed1996

Detection of Neisseria gonorrhoeae from air-dried genital samples by single-tube nested PCR.

A single-tube nested PCR method was developed for the detection of Neisseria gonorrhoeae. The optimized assay had a detection limit of less than 0.3 cell. Five different storage conditions for gonococcal specimens were compared with respect to the PCR detection of bacteria. For air-dried gonococcal slides containing three bacteria, DNA was detected after 8 weeks at ambient temperature, and for slides containing 300 bacteria, DNA could be detected after 24 weeks at ambient temperature. Air-dried storage combined with analysis by the single-tube nested PCR and a commercially available PCR (Amplicor) was used to test 350 cervical specimens from women in the West African island nation of Cape Verde. The in-house PCR detected 17 cases of N. gonorrhoeae infection, while the Amplicor system detected 14 cases of N. gonorrhoeae infection. No specimen was negative by the in-house PCR assay and positive by the Amplicor PCR. This sensitive nested PCR assay, combined with air-dried storage, allows for the detection of gonococci when specimen storage and transport times are extended and freezing conditions are not available.

Female↗
PubMed1996

Differentiation of Chlamydia spp. by sequence determination and restriction endonuclease cleavage of RNase P RNA genes.

The amplification of DNA from Chlamydia trachomatis by PCR with degenerated primers yielded a 345-bp fragment of the putative RNase P RNA gene. From the deduced DNA sequence of this gene in C. trachomatis, a modified primer pair was designed. The primer pair was subsequently used to obtain the corresponding gene products from Chlamydia pneumoniae and Chlamydia psittaci. Sequence comparisons revealed similarities of 76.6% between C. trachomatis and C. pneumoniae, 79.5% between C. trachomatis and C. psittaci, and 84.7% between C. pneumoniae and C. psittaci. Furthermore, the three species were differentiated by fragment length polymorphism analysis after restriction enzyme cleavage of the PCR products. Sequence variations among 14 serotypes of C. trachomatis were confined to one purine base substitution in the putative RNase P RNA gene of lymphogranuloma venereum strains L1 to L3. Complete sequence similarity was found for nine strains of C. pneumoniae of different geographic origins. Taken together, our results indicate a possibility of the general application of this method in clinical bacteriology. Analysis of the secondary structures of the putative RNase P RNA genes from the different Chlamydia species suggested that a novel structural element in the domain of RNase P RNA is involved in base pairing with the 3'-terminal CCA motif of a tRNA precursor. This structure has not previously been found among RNase P RNAs of members of the division Bacteria.

Base Sequence↗
PubMed1996

Genital chlamydial infection among women in Nicaragua: validity of direct fluorescent antibody testing, prevalence, risk factors and clinical manifestations.

OBJECTIVE: To validate the performance of a direct fluorescence antibody (DFA) test and to determine the prevalence, risk factors and clinical manifestations of cervical chlamydia infection in different groups of women in Nicaragua. STUDY POPULATION: 926 women, 863 routine clinic attenders (mean age 27 years) and 63 sex workers (mean age 25 years) attending health centres in León, Corinto, Matagalpa and Bluefields. METHODS: Cervical specimens were examined using the Syva MicroTrak test system with a cut-off of 10 or more elementary bodies (EBs). The DFA results were validated by a one-step polymerase chain reaction (PCR) assay. Discordant results were further examined in nested PCR assays directed at two different target genes. An interviewer-administered questionnaire and a standard gynaecological examination were completed. RESULTS: Sensitivity of DFA was 80.1%, specificity 98.3%, and positive and negative predictive values 62.5% and 99.3%, respectively. Values were lower in locations where samples thawed because of electricity breaks and higher among sex workers. The majority of discordant results was confirmed as positive in nested PCR assays. Prevalence of cervical chlamydia infection based on positivity in DFA and/or PCR ranged from 2% among routine clinic attenders aged 35 years or older, to 8% among adolescent clinic attenders, and to 14% among sex workers. Among routine clinic attenders, young age (odds ratio [OR] 3.6, 95% confidence intervals [95% CI] 1.4-8.9 for women aged 15-19 years as compared with 1 in women 25 years of age or older) and use of oral contraceptives (OR 4.0, 95% CI 1.7-9.6) were the only statistically significant risk factors identified in multivariate logistic regression analysis. Presence of mucopurulent cervical discharge (OR 5.9, 95% CI 3.0-11.5) and presence of ectropion (OR 2.6, 95% CI 1.1-6.5) were the clinical signs independently associated with infection. CONCLUSIONS: Our results indicate that the DFA test was sensitive and specific while the performance of the PCR assay depends on adequate storage of samples. Genital C trachomatis infection is a common health problem among women in Nicaragua. The wide implementation of syndromic STD management algorithms together with health education programmes aimed at young people is the most promising approach to control STD in Nicaragua.

Adolescent↗
PubMed1996

Amplification of human short tandem repeats from medieval teeth and bone samples.

The suitability of typing hypervariable DNA loci for the genetic analysis of prehistoric populations is demonstrated for the first time. Alleles of the human short tandem repeat locus VWA31/A have been amplified from ancient teeth and bone samples derived from an early medieval burial site at Weingarten, Germany, using the polymerase chain reaction. The DNA results for 76 individuals reveal remarkable similarity of the allelic frequencies between the past and modern populations. A surplus of apparent homozygotes in the ancient population is most likely due to a stochastic problem of amplification of degraded DNA. Therefore technical obstacles for the application to ancient DNA were evaluated. The substantial perspectives of using microsatellite typing for the analysis of heritable diseases, determination of relatedness, and establishment of genealogies in prehistoric populations are outlined.

Alleles↗
PubMed1996

[Lipogranuloma of the orbit. Apropos of a case].

We present a case of orbital lipogranuloma with a supero-nasal retrobulbar localisation associated with axial proptosis and major choroidal thickening. No clinical sign of inflammation, neither orbital nor in the posterior segment, was revealed. The systemic work-up as well as paraclinical data were within normal limits. The diagnosis was made after histopathologic examination of the biopsy taken via superior orbit. Outcome was favorable following long-term systemic corticotherapy. Orbital lipogranuloma is a rare particular form of orbital pseudotumour of unknown etiology. It is characterized, histologically, by orbital fat necrosis. Pathogenesis remains controversial. The differential diagnosis includes iatrogenic lipogranulomas secondary to sinus surgery (paraffinoma), orbital granulomas in sarcoidosis and Wegener's disease and orbital lymphomas. The prognosis is usually good following treatment with steroids.

Adult↗
PubMed1995

aDNA analysis in paleopathology: mini-review and prospects.

The epidemiology of human diseases is a major indicator of living conditions. Cardiovascular diseases are said to be a phenomenon of modern industrial societies, but infectious diseases have always been an indicative determinant in historic and prehistoric human populations. The spread of infectious agents is closely related to socioeconomic factors, e.g., nutritional status, population density, and hygienic conditions. Gathering more paleoepidemiological data on infectious diseases would also be helpful in studying human adaptivity and the evolutionary capability of pathogenic microorganisms. Until now, the collection of paleoepidemiological data was restricted to those human diseases that left traces on the skeletal remains, e.g., the terminal stages of syphilis, tuberculosis, and leprosy, or degenerative disorders of the joints. With modern molecular techniques, the spectrum of detectable infectious and heritable human diseases will foreseeably be enlarged. By detecting the infectious agent, or analysing the genetic codes, it will be possible to focus systematically on those diseases that either lead to sudden death or do not affect the skeleton because of their specific course.

DNA Mutational Analysis↗
PubMed1995

[aDNA--a new approach to old questions].

aDNA-analyses are presented for ancient bones, teeth, soft tissues and dried body fluids. The implications and perspectives for Historical Anthropology are discussed. Methods are described on examples of molecular sex determination and kinship analysis. Finally, first amplifications of DNA-sequences from pathogenes of tuberculosis and plague from ancient skeletal material are reported.

Anthropology, Physical↗
PubMed1994

Comparison of DNA extraction and amplification from ancient human bone and mummified soft tissue.

South american precolumbian male mummies were employed as source material for a comparative investigation of bone and soft tissues by DNA analysis. The suitability of the DNA extracts from both sources was tested and evaluated by their effectiveness as target DNA in PCR amplifications. The results suggest that skeletal material should be given preference over soft tissues for PCR analysis if the material is severely degraded. This seems to be independent of the specific anatomical origin of the samples.

Anthropology, Physical↗
PubMed1994

Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan.

The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of > or = 1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies.

Acute Disease↗