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H Pfeiffer

Publications and source records attributed to H Pfeiffer.

At least 55 records · Page 3Linked to original sources
PubMed1998

Reproducibility of mtDNA analysis between laboratories: a report of the European DNA Profiling Group (EDNAP).

The aim of this collaborative exercise was to determine whether uniformity of mtDNA sequencing results could be achieved among different EDNAP laboratories. Laboratories were asked to sequence mtDNAHV1 region (16024-16365) from three bloodstains, proceeding in accordance with the protocol and strategies currently used in each individual laboratory. Cycle sequencing was used by 11 laboratories and solid phase single stranded sequencing was used by one laboratory. Different PCR strategies and PCR conditions were used by the different laboratories. Three laboratories used semi-nested PCR, two nested PCR, three direct amplification of HV1 and four amplification of overlapping fragments covering the HV1 region. Despite the diversity of methodologies used, all the laboratories reported the same results. The successful result of this exercise shows that PCR based mtDNA typing by automated sequencing is a valid, robust and reliable means of forensic identification despite the different strategies and methodologies used by the different laboratories.

DNA Fingerprinting↗
PubMed1998

Potential DNA mixtures introduced through kissing.

The use of saliva samples is an alternative to blood samples when a large number of control samples are to be compared by DNA investigations. The most convenient and safe method is by using cotton wool swabs. In this investigation the average DNA content of saliva samples taken by three different sampling techniques (i. e. cotton wool swab, filter paper, liquid saliva) was compared. In addition the possibility of a DNA mixture of saliva samples after intensive kissing was investigated by taking samples from voluntary pairs. Mixed STR patterns were found in five samples but restricted to the first sampling after kissing within max. 60 s.

DNA↗
PubMed1998

Mitochondrial DNA extraction and typing from isolated dentin-experimental evaluation in a Korean population.

This study reports mtDNA polymorphisms in both hypervariable segments HV1 and HV2 of the non coding D-loop region from 60 unrelated Koreans. In contrast to two previous Korean data base studies, mtDNA was extracted separately from pulp tissue and root dentin of teeth obtained from dentists. Dentin turned out to be a reliable source of mitochondrial DNA. This can be of practical importance in forensic identification case work after a long post-mortem interval since pulp decomposes rapidly. The extraction method is explained in detail. The mtDNA polymorphisms obtained from 60 teeth of unrelated Koreans were compared with the already existing Korean data base.

Asian People↗
PubMed1998

Attempted homicide by electrocution.

Attempted homicide by the application of a high-voltage, low-amperage current is reported in an elderly male. An electrician constructed an apparatus and applied the current to wet towels placed on the abdomen of the victim sleeping next door. The attempt was unsuccessful and resulted in burns only. The victim was hospitalised and died 3 weeks later. A causal connection could not be established between the attempted electrocution and the demise of the victim.

Aged↗
PubMed1998

Heteroplasmic substitutions in the mitochondrial DNA control region in mother and child samples.

The sequences of the two hypervariable regions of the mitochondrial DNA control region (HV1 and HV2) from close maternal relatives (mother-child pairs) were compared to determine the frequency of mutations between two generations. A total of 68 blood samples were sequenced only in HVI and 86 were analysed for HV1 and HV2. The intergenerational comparison led to the identification of six heteroplasmic point mutations affecting the children only. In one case a heteroplasmy of the maternal sequence was resolved to homoplasmy in the corresponding sequence of the child.

Adult↗
PubMed1998

Phylogenetic resolution of complex mutational features at Y-STR DYS390 in aboriginal Australians and Papuans.

Y-chromosomal short tandem repeats (STRs) are used for the study of male aspects of human evolution as well as for forensic applications and paternity testing. Both applications require an understanding of the underlying mutational mechanisms that create variability. We describe complex mutations at the substructured DYS390 STR locus in 97 natives of the New Guinea/Australian region. Sequencing of short alleles in these populations indicates multirepeat deletions. All samples are further characterized using the five additional Y-STR loci DYS19, DXYS156-Y, DYS391, DYS392, and DYS393. Phylogenetic analysis of the resulting haplotypes yields ethnically specific clusters predating the settlement of Australia and Papua New Guinea (although archaic Homo sapiens or Homo erectus lineages are absent). The phylogeny confirms that DYS390 violates the stepwise mutation model and demonstrates that the DYS390 locus mutates relatively rapidly and retains its variability after structural change.

Alleles↗
PubMed1997

Characterisation of antibiotic moenomycin A interaction with phospholipid model membranes.

Using a combination of physico-chemical techniques (MAS NMR, DSC, freeze-fracture electron microscopy, molecular modelling) the antibiotic moenomycin A was found to be anchored by its hydrophobic chain into multilamellar POPC membranes. The lamellar phase structure of the modified membrane is retained, while moenomycin A in water at different concentrations does not form any other but isotropic phase structures. The mobility of POPC molecule segments is reduced with increasing moenomycin A concentrations. Freeze-fracture electron microscopy images show ripple like structures for low moenomycin A concentrations, which are rare for high concentrations. A sugar-group network of the antibiotic seems to cover the whole membrane surface for molar ratios moenomycin A/POPC of 1:2, which is supported by 13C-MAS (Magic Angle Spinning) 31P-NMR, and molecular modelling.

Bambermycins↗
PubMed1997

Origin of hepatocellular carcinoma recurring after allotransplantation revealed by microsatellite analysis.

A hepatocellular carcinoma was resected from a liver allotransplant after the patient's original organ had been removed because of a liver carcinoma. DNA analysis was performed to explore the origin of the carcinoma cells. DNA extracted from the carcinoma tissue, from the carcinoma free liver tissue, and from other cells of the recipient underwent polymerase chain reaction amplification for seven microsatellite systems and the X-Y amelogenin system. The allelic pattern from the carcinoma tissue was identical with that from the patient and differed from the DNA profile of the liver tissue. The result confirmed the assumption that the carcinoma tissue had originated from the patient and not from the donor.

Adult↗
PubMed1995

Estimation of chronologic age using the aspartic acid racemization method. I. On human rib cartilage.

Determinations of chronologic age are of great importance in forensic science. At present the aspartic acid racemization method on teeth provides one of the best means in adult individuals. However, if teeth are not available, some other stable tissue has to be used. In this study, the applicability of cartilage from the ribs has been tested. Specimens of rib cartilage were obtained at autopsy from 24 individuals aged 0.2-96 years. An acid-soluble peptide (SP) fraction and an insoluble collagen-rich (IC) fraction were prepared, and the ratio of D/L aspartic acid was determined using the HPLC technique. The correlation coefficient between the D/L ratio and age was r = 0.91 in SP and r = 0.97 in IC. It thus seems as if cartilage from non-weight-bearing areas may be a useful source of tissue for the estimation of chronologic age with the aspartic acid racemization method when teeth are not available.

Adolescent↗
PubMed1995

Estimation of chronologic age using the aspartic acid racemization method. II. On human cortical bone.

Over the last 20 years a new chemical method, base on the racemization of aspartic acid, has been developed to be used for the estimation of chronologic age in adult individuals. The method has a good accuracy when used on dental enamel, dentine and cartilage. However, in forensic and archeological cases teeth and cartilage are not always available. Since preliminary studies have shown that there are some age-related changes of the D/L aspartic acid ratio also in bone, this study was carried out to further explore if the method could be used for age estimations of bone. Bone samples from 24 individuals, aged 0.2 to 95.6 years were analysed for the D/L ratios with HPLC-technique. Two different fractions of the bone were examined, an acid-soluble peptide fraction and an acid-insoluble collagen-rich fraction. The analyses showed age-related racemizations in both fractions, although of different rates. The correlation coefficients with age were 0.72 in the peptide fraction, and 0.84 in the collagen-rich fraction. It thus seems as if bone may be used for age estimations when more stable tissues like dentine and cartilage are not available.

Adolescent↗
PubMed1994

Estimation of dental age using HPLC-technique to determine the degree of aspartic acid racemization.

Age determinations of adult individuals are of great importance within the forensic sciences. Presently, age changes in the teeth provide good means for this. The best method up to now has been "Gustafson's method" with modifications. Over the last 10 years a new chemical method, based on the racemization of aspartic acid in enamel and dentine, has been developed. Enamel and dentine belong to the very few tissues that do not have metabolic turn-over after formation. Both reliability and validity have been shown to be high, and this method therefore seems to be the best choice for the future. However, most studies to date have been using expensive and special instruments (gas chromatographs or amino acid analyzers) for these determinations. This study was performed to explore if the same determinations can be carried out with ordinary HPLC technique. It was shown that there is a good correlation between the ratio of D- and L-forms of the aspartic acid and age of the tooth. The correlation coefficient was 0.97, which is close to those presented with the other techniques, where r has been 0.95 - 0.99. The prediction of an individual age can be made with a 95% confidence interval of about +/- 12 years.

Adolescent↗
PubMed1993

A weighted time budget approach for the assessment of cognitive and social activities.

An instrument designed to assess potentially challenging cognitive and social activities in a wide range of both psychiatric and normal study populations is described in this paper. The technique used combines traditional time budget approaches with an additional, significant component, i.e. a rating indicating the amount of challenge for each activity that is sampled. Separate ratings reflecting the subject's and the interviewer's perspective are generated. Along with a detailed description of this weighted time budget instrument, preliminary data regarding practicality, reliability and validity are reported. An analysis based on time budget interviews with 30 schizophrenic patients showed overall interrater agreement to average 84% (kappa = 0.72). In a study with a possible bearing on the concurrent validity of the instrument, relapsing schizophrenics significantly differed from stable subjects in weighted time budget indices.

Activities of Daily Living↗
PubMed1991

[Determinations by indirect calorimetry need not be expensive and technically complicated. A new measurement system and its validation].

Presentation of a newly conceived measuring instrument to determine the energy expenditure of critically ill patients at the bedside by means of indirect calorimetry. The special advantages of the measuring instruments are easy handling, little maintenance and very low working expenses and prime costs. The accuracy of measurement is considerable nd is comparable with that of other measuring methods, as has been established by an extensive validation.

Calorimetry, Indirect↗
PubMed1990

Marburger concept for computer-aided acquisition, processing and documentation of patient data in the intensive care unit.

The authors report on their experience with the computer-aided acquisition, processing and documentation of patient data in an intensive care unit. The goal of an effective data and information collection system in the intensive care unit is to make therapy, and the patients respond to it, recognizable and understandable through the clear and complete representation of the patients conditions. The focal point of the data documentation is the medical record. In the implementation of a computer-aided data documentation and processing system the application of one central PC is unpractical. Each bed will be equipped with its own PC, and all the individual PCs will be connected to one central PC, which functions as server, and to connected to another PC in the doctors room. The data will be managed in a powerful database-management-system and be stored on an optical-disk. The development of an effective man/machine interface is especially important. In addition we can promote the user acceptance in other ways, so as to ensure a concrete benefit for each user group.

Electronic Data Processing↗
PubMed1989

[The effect of food supplements on the bioavailability of breast milk for premature infants--fecal fat and carbohydrate excretion].

Faecal excretion of fat and carbohydrates was studied in 14 preterm infants fed on raw mother's milk (group I) or banked fortified human milk (group II) at days 7, 14, 21 and 28 of postnatal life: group I: n = 5; 31.0 +/- 2.0 weeks; 1954 +/- 441 g; group II: n = 9; 32.0 +/- 1.0 weeks; 1806 +/- 176 g. Mixtures of amino acids, peptides, minerals, dextrine and maltose were designed for fortifying banked human milk. There were no significant differences between faecal excretion of fat and carbohydrates in both feeding groups. The investigated human milk fortifier helps to realize the protein-energy ratio needed in preterm infants with well tolerable volumes of feeding and without stressing their limited digestive capacity.

Biological Availability↗
PubMed1987

[Music improvisation with schizophrenic patients--a controlled study in the assessment of therapeutic effects].

The effects of a course of music therapy with free improvisation, consisting of 27 sessions over a period of 6 months, were examined in a controlled study of matched therapy and waiting group, each comprising 7 patients with a diagnosis of schizophrenia or schizoaffective psychosis. The psychopathologic picture having essentially remained unaltered on the measuring instrument used (Lorr scales), significant positive changes were found in the self-assessment questionnaires completed by the participants. Improvements in recreational and social behaviours could not be shown. The disease and reintegration processes took similarly positive courses in both groups, supported by the extensive range of psychiatric/psychotherapeutic services available in the Munich area. The improvising orientation of the music therapy course had mostly been approved of by the patients, it however also gave rise to a desire for more structuring and a more goal-directed therapeutic approach. A tendency towards the initial values, i.e. a deterioration, was stated in the therapy group at follow-up six months post-therapy.

Adult↗