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Biomedical subjects

H Kreibich

Publications and source records attributed to H Kreibich.

At least 19 recordsLinked to original sources
PubMed1998

Development and validation of methods for the trace determination of PCBs in biological matrices.

A method was developed to determine trace concentrations of a range of individual PCB congeners in biological samples (grass, silage, cattle faeces and milk-fat) which were taken from rural or 'background' areas of the UK, in order to prepare a mass balance of PCBs in grazing, lactating cows. A simple milk-fat extraction method was compared to Soxhlet extraction and to whole milk extraction. Results indicated that simply boiling milk-fat in hexane with sodium sulphate present gave a comparable extraction of PCBs to other methods. A clean-up method was devised using acid treated silica gel followed by basic alumina chromatography. Grinding frozen grass or silage with sodium sulphate followed by Soxhlet extraction was found to be the most effective method for these matrices, whilst avoiding the potential contamination/loss of PCBs which can be incurred by air, oven or freeze drying. Soxhlet extraction of cattle faeces, after grinding with sodium sulphate, was found to be effective. A rigorous clean-up was devised which involved passing the extracts through silica gel and acid treated silica gel, followed by size exclusion chromatography (gel permeation chromatography, SEC). 13C12 labelled PCBs were used as recovery standards, quantification was performed using GC-MS. A quality control regime and method validation results are presented. The milk analysis method gave within batch mean recoveries of 69-96%, and within batch standard deviations between 1 and 10%. The vegetation analysis method gave within batch mean recoveries of 91-116%, and within batch standard deviations between 1 and 11%. The batch to batch mean recovery for milk analysis was 90%, with an RSD of 2% for high spikes and 5% for low spikes; for vegetation analysis the batch to batch average recovery was 106%, with an RSD of 14% for high spikes and 11% for low spikes. sigma PCB concentrations (53 congeners) of 3900 +/- 790 pg g-1 milk-fat, 1300 +/- 420 pg g-1 dry matter (DM) cattle faeces, 630 +/- 140 pg g-1 DM silage and 1350 +/- 580 pg g-1 DM grass were found during the study.

Animals↗
PubMed1997

[The status of diagnosis of Barrett esophagus. An analysis of 1000 histologically diagnosed cases].

OBJECTIVE: To evaluate the quality of diagnosis in cases of Barrett's oesophagus (BOe). It was examined whether: (1) there had been regular pre-treatment investigations;(2) characteristic mucosal changes had been recognized by endoscopy; (3) a diagnosis of intraepithelial neoplasia had been made more often than of advanced Barrett carcinoma. PATIENTS AND METHODS: Endoscopic and associated bioptic reports on 1000 consecutive patients with histologically confirmed BOe, seen between 1990 and 1995, were analysed. (Average age was 63 +/- 14.3 years; male to female ratio: 2.2:1). RESULTS: In 85.1% of patients the histological diagnosis was BOe without dysplasia. The neoplasias consisted of carcinoma in 8.8%, suspected carcinoma in 0.5%, actual or suspected low-grade dysplasia in 4.6%, actual or high-grade dysplasia in 1.0%. Endoscopic diagnosis in cases without neoplasia was in 60.8% correct for actual BOe or suspected BOe. At endoscopy dysplasia was suspected in 5.4%. The diagnosis or suspected diagnosis of Barrett's carcinoma was correct in 69%. Repeat endoscopy a year after the initial diagnosis was performed in 9.4% with BOe and no neoplasia. Repeat endoscopy was performed in 37.5% of patients with an initial diagnosis of suspected low-grade dysplasia, in 43.3% with low-grade dysplasia, in 42.9% of suspected high-grade and in 100% of actual high-grade dysplasia. CONCLUSION: Neoplasia in Barrett's oesophagus is found too late. Only half of the histologically confirmed cases are found by endoscopy and follow-up is not sufficient.

Aged↗
PubMed1990

["Public health and scientific-technical progress"].

The tasks of the hygienic and social-medical oriented special disciplines are summarizingly presented in relation to the state of the development of sciences and the social changes at the turn of the years 1989/90. The Hygienic Congress 1990 at Berlin was directed to the contribution of hygienic and social-medical disciplines during the practical performance of health protection of the population under the conditions of the scientific-technical progress.

Germany↗
PubMed1989

[The search for interventional priorities for the prevention of chronic diseases in females employed in the health service].

With a view of clearing up certain influence of the working and living conditions on health, some results of control examinations in occupational medicine from the years 1985 to 1988 of women employed in the health service (n = 86,769) were analyzed and compared with those of the investigations carried out on all women in the GDR (n = 662,578). The tracking down of significant deviations in the age-standardized prevalence rates for chronic health disturbances was performed by means of a specialized computer programme for the health of women and for 7 occupations. Among other things, it was possible to prove permanently increased prevalence rates for chronic diseases of the kidneys/urinary passages in the overall population and in the personnel for laboratory diagnostics, as well as an increased prevalence of hypertension in day nursery educators. The elaborated strategy for tracking down work-related diseases and chronic diseases proved effective and can also be used for issues in other economic sectors.

Chronic Disease↗
PubMed1982

[100th anniversary of Robert Koch's discovery of Mycobacterium tuberculosis (author's transl)].

A brief account of Robert Koch's biography is followed by reference to the past 100 years and the change that has occurred in that period to the prospects of tuberculosis, including genital tuberculosis.--Comprehensive tuberculosis control programmes in many industrialised countries, including the GDR, have contributed to significant reduction of tuberculosis incidence. It has been wiped out as a mass epidemic. Today, genital tuberculosis does no longer grow manifest by the classical pattern of massive tumour growths which reach up to the mesogastrium. It is rather manifested in discrete latent forms, often detected along with sterility diagnosis or as an accidental finding. Nevertheless, the general risk of tuberculosis must not be belittled, since it still is a global health problem.

Animals↗