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Biomedical subjects

G Raabe

Publications and source records attributed to G Raabe.

At least 19 recordsLinked to original sources

Cytokeratin pattern of clinically intact and pathologically changed oral mucosa.

The various cytokeratin polypeptides in oral epithelia are expressed in dependence on site and formation of a stratum corneum. Certain cytokeratins occur permanently and others occasionally. In fibrous hyperplasia and Lichen ruber planus, patterns of cytokeratins did not deviate significantly from normal. In some but not all cases of squamous cell carcinoma and leukoplakia studied, marked aberrations of pattern were characterized by (i) appearance of cytokeratin No. 19, (ii) somewhat more frequent occurrence of cytokeratins Nos. 8 and 18, (iii) proteolytic modifications of cytokeratins, and (iv) partial loss of a few site-specific cytokeratins. The aberrations may be taken as additional diagnostic criteria for differentiation between non-aggressive and potentially aggressive leukoplakic lesion, even if they are not correlated with the conventional histological grading of dysplasia.

Adolescent

[Hyperplasiogenic polyps and stomach carcinoma risk--experiences following 1074 polypectomies and follow-up studies].

In 731 hyperplasiogenic polyps which have been removed by endoscopical polypectomy there were ten polyps with an early cancer and eight polyps with severe dysplasias (borderline lesions) as well as one polyp, in which an advanced carcinoma had developed. This is to date the greatest series of hyperplasiogenic polyps with malignant transformation. In addition, in nine patients with hyperplasiogenic polyps carcinomas could be discovered, i.e. a rate for malignancy of 3.8%. It seems that stomachs with multiple polyps are particularly endangered. The recurrence rate on follow-up examinations covering a period of up to eight years was 36.1%.

Cell Transformation, Neoplastic

Discordant findings in chorionic villus direct preparation and long term culture--mosaicism in the fetus.

Prenatal cytogenetic study of chorionic villi showed a discrepancy between a normal female karyotype 46,XX in the direct preparation after short-term incubation, and a 45,X karyotype in the long-term culture. The subsequent amniocentesis revealed a normal karyotype in three cultures and a 45,X/46,XX mosaicism in one culture. Cytogenetic analysis of chorionic villi after termination of the pregnancy showed a normal karyotype in the direct preparation and a 45,X/46,XX mosaicism in the long-term culture. Fetal lymphocytes showed normal karyotypes, whereas fibroblast cultures revealed a 45,X/46,XX mosaicism.

Chorionic Villi Sampling

Cell proliferation in chorionic villi at different gestational ages, as analyzed by premature chromosome condensation.

The technique of premature chromosome condensation (PCC) was adapted to human first-trimester chorionic villi cells to analyze the cell-cycle kinetics of interphase chromatin. Uncultured cells of the cytotrophoblast (CT) and the mesenchymal core (MC) were obtained by a two-step digestion. PCC was induced by fusion of the chorionic interphase cells with mitotic Chinese hamster ovary or HeLa cells. Cells showing PCC in G1 (classes 1-6), S, and G2 were found. To analyze further the proliferation stages of chorionic G1 interphases, the proliferation potential index (PPI) of 34 placentae recovered between the 8th and 12th week of gestation was determined. The mean PPI found in the CT and MC cells ranged from 18% to 73%, values similar to those described for intensely proliferating tissues. The highest mean PPI value (73%) was observed in CT cells from placentae recovered at the 9th week of gestation, indicating a high specific proliferative activity of CT cells at this developmental stage.

Animals

Paracentric inversion 14.

A new familial case of paracentric inversion of chromosome 14 inv(14)(q24.1q32.1) ascertained by multiple abortions in a female carrier is presented. A review of the literature revealed 14 cases of paracentric inversion 14 recorded so far. According to the different breakpoints, two major groups of inversions of the long arm of chromosome 14 can be recognized.

Abortion, Habitual

[Comparative experimental animal studies for testing the usefulness of formalin- and glutaraldehyde-pretreated umbilical cord veins as artery replacements].

Formalin-fixed (F) and glutaraldehyde-pretreated (G) umbilical veins (n = 24) were interposed in the infra-renal aorta of dogs. The follow-up period was 1 year. Early complications with significant differences included 2 occlusions and 3 deaths (41.6%) in group F, 1 occlusion and 1 death (16.6%) in group G. Ten animals of group G and 7 of group F were alive at 1 year, 7 transplants of each of both groups were angiographically and macroscopically patent (25%). Four aneurysms (33.3%) existed angiographically and showed good collateral circulation angiographically (25%). Four aneurysms (33.3%) existed angiographically and macroscopically in group F (statistically significant). Histologically, group G was found to have a delayed resorption and an earlier beginning of connective-tissue proliferation as compared to group F. Considering early and late findings, G-pretreatment is preferable to F-treatment of umbilical veins.

Animals

Pattern of oral cytokeratins. III. SDS-electrophoretic analysis and immunoblotting of cytokeratins in leukoplakias and squamous cell carcinomas of the oral mucosa.

The frequency of the occurrence of cytokeratins analyzed SDS-electrophoretically in 20 leukoplakic lesions and 14 squamous cell carcinomas of the oral mucosa has shown a picture of "restlessness" with some quantitative, some qualitative deviations from the locally normal pattern of cytokeratins. In most cases the basic pattern typical for the oral mucosa was still recognizable, except for three highly undifferentiated carcinomas. The variations of the cytokeratin pattern existed independently of the clinical form of leukoplakia and of its histological degree of dysplasia. The striking findings in some, but not all cases were: --the presence of cytokeratin no. 18 as a major component which normally appears rarely and faintly, and of cytokeratin no. 19, which is not normally detectable electrophoretically within the whole oral mucosa; --the absence of cytokeratins no. 1-3 despite of the cornification which was reliably proved by histology; --the appearance of the proteins having molecular mass values of 42 kDa and less which very probably may be the products of partial keratinolysis as evidenced by immunoblotting with monoclonal and polyclonal antibodies to cytokeratins. Among these proteins a proteolytically modified cytokeratin no. 19 of only 38 kDa was found.

Antibodies, Monoclonal

Paracentric inversion 11.

A new familial case of paracentric inversion of chromosome 11 inv(11)(q21q23.3) ascertained by multiple abortions in a female carrier is presented. A review of the literature shows 19 further cases of paracentric inversion 11. According to the different breakpoints, the inversions of the long arm of chromosome 11 may be classified into three types.

Abortion, Habitual

A new case of pericentric inversion 20.

A prenatal diagnosis from a chorionic villi biopsy revealed a pericentric inversion of chromosome 20. The child's father also carries the inverted chromosome. The breakpoints p13q11.2 differ for 4 of the 5 published cases of inversion 20.

Adult

Action of chronic peracetic acid (wofasteril) administration on the rabbit oral mucosa, vaginal mucosa, and skin.

In a long-term experiment on rabbits 0.2% peracetic acid (0.5% Wofasteril) was distributed upon the dorsal skin, the oral and the vaginal mucosa 3 times per week for 12 months. Each type of tissue was applied 153 individual doses. The histological examinations did not yield dysplasias in the sense of a carcinogenic action of peracetic acid. Despite the very high dosage as it will never be demanded in therapeutical measures, the mucosal tissues under study neither showed inflammations nor scar formation after 12 months of administration. Merely in the dorsal skin a loss of minute accessory hairs in the animal fell was observed. From morphological points of view it seems justified to extend the indication of 0.2% peracetic acid (0.5% Wofasteril) to the mucosal membrane for preparatory arrangements of surgical interventions and for therapeutical measures in bacterially induced inflammatory processes. Clinical testing can be recommended. Before permanent use of peracetic acid for hand disinfection the possible hazards of depilation must be tested dermatologically.

Acetates

Pattern of oral cytokeratins. II. SDS-electrophoretic analysis of cytokeratins in reactive hyperkeratoses and Lichen ruber planus of the oral mucosa.

In SDS-electrophoresis the hyperortho- and hyperparakeratoses showed cytokeratin patterns fairly similar to those in the normal masticatory mucosa in cases of reactive hyperkeratosis due to mechanical stimulatory action; however, in Lichen ruber planus they agreed only incompletely. The site-specific, normally stably expressed cytokeratins of the mucosa-type concerned were likewise regularly demonstrable in the pathologically changed tissue specimens under study, except cytokeratin no. 1 which is known to be a reliable indicator of keratinocyte cornification merely in orthological but not in pathological conditions. Deviating from the normal cytokeratin pattern in the oral mucosa, a more frequent and more expressed occurrence of cytokeratins no. 17 and 18 was observed in Lichen ruber planus. In 4 extraordinarily reactive hyperkeratoses, among these 2 papillomas the cytokeratins no. 7/13 were present.

Biopsy

[Hyperplasiogenic polyps and risk of stomach cancer].

In 731 hyperplasiogenic polyps which have been removed by endoscopical polypectomy there were 9 polyps with an early cancer and 8 polyps with severe dysplasias (borderline lesions) as well as 1 polyp, in which an advanced carcinoma has been developed. This is the outstanding greatest number of hyperplasiogenic polyps with a malignant transformation. In addition in 9 patients with hyperplasiogenic polyps carcinomas could be discovered, i.e. a rate for malignant developments of 3.7%. It seems that stomachs with multiple polyps are endangered in particular. The recurrence rate of follow-up examinations covering a period of up to 8 years was 36.1%.

Cell Transformation, Neoplastic

Structural rearrangements of chromosome Nr 8 involving 8q12--a primary event in pleomorphic ademona of the parotid gland.

Nine pleomorphic adenomas of the human parotid gland were investigated. Within this series the group of cases having clonal aberrations of chromosome Nr 8 predominates. The occurrence of cases with trisomy-8 and cases with structural rearrangements involving a breakpoint in 8q11-8q13 allows a further subdivision of this group of tumors. Our special interest in this paper is devoted to the latter group. The hypothesis is proposed that in these cases the chromosomal rearrangement is the primary event in tumorigenesis, leading to activation of a so far unknown oncogene located most likely at 8q12. The translocations to different recipient chromosomes may serve as sign posts to transcriptionally active chromosomal domains in the salivary gland.

Adenoma