Biomedical subjects

K Kraft

Publications and source records attributed to K Kraft.

114 records · Page 7Linked to original sources

PubMedDate not supplied

Warthin's tumour is not an Epstein-Barr virus related disease.

BACKGROUND: The histogenesis of Warthin's tumour (WT) is controversial. A possible role for Epstein-Barr virus (EBV) has been suggested. MATERIALS AND METHODS: Twenty formaldehyde-fixed, paraffin-embedded blocks of WT from the parotid gland were examined for the presence of EBV. In situ hybridisation was performed using EBV encoded small nuclear RNAs (EBER1/2) probes labelled with fluorescein isothiocyanate. An EBV-positive P3HR-1 cell line processed to paraffin wax was used as a positive control and a brain section as negative control. RESULTS: EBER1/2 could not be found in the neoplastic epithelial cells in any of the tumours nor in the adjacent normal parotid tissues. Individual positive lymphocytes were present in 7 tumours. CONCLUSIONS: These results indicated that EBV is not involved in the pathogenesis of WT.

Adenolymphoma↗

PubMedDate not supplied

High-resolution DNA flow cytometry in oral verrucous carcinoma.

The classification of verrucous carcinoma as an entity unto itself or as a variant of well differentiated squamous cell carcinoma is controversial. To contribute new insights into the biological behavior of this rare tumor, we applied DNA flow cytometry to three node-negative verrucous carcinomas of the oral cavity. All tumors expressed a single aneuploid cell population. One of the patients experienced three courses with local recurrence. All secondary tumors retained the initially established aneuploid clone. The development of aneuploidy is thus a cytogenetic event common to both verrucous and squamous carcinoma of the oral cavity.

Aged↗

PubMedDate not supplied

Stability of aneuploid clones during oral squamous cell carcinoma metastasis.

BACKGROUND: The development of aneuploid clones contributes to the expression of metastatic growth properties in head and neck squamous cell carcinomas. Controversy persists as to whether aneuploid clones acquire an autonomous metastatic potential or instead activate diploid tumor cells to disseminate. PATIENTS AND METHODS: DNA flow cytometry was performed on 73 primary oral squamous cell carcinomas and their synchronous lymph node metastases as well as on 20 other patients who experienced delayed manifestation of occult lymph node involvement. RESULTS: Diploidy for both the primary and metastatic tumor was recognized in 6.5% of patients; 5.4% showed a shift from diploidy to aneuploidy while 3.2% had aneuploid tumors that associated with diploid metastases. Aneuploid clones in corresponding lesions were identified in 84.9% of cases. Despite the wide variation of individual DNA contents, 86.1% of the latter group expressed aneuploid clones with identical DNA indices in both the primary and metastatic tumors. The stability of initially established aneuploid clones was monitored even after 58 months of occult metastasis growth. CONCLUSION: Lymph node metastases preferentially originate from pre-existing aneuploid tumor clones.

Aneuploidy↗

PubMedDate not supplied

Differentiation-related p53 protein expression in nondysplastic sinonasal inverted papillomas.

To clarify p53 protein expression in nondysplastic sinonasal inverted papillomas, archived surgical specimens from 19 patients were studied using immunohistochemistry. Staining results were compared between inverted papillomas and adjacent, nonpapillomatous nasal mucosa. Further, immunoreactivity was compared between columnar (respiratory), transitional (cuboidal), and squamous epithelium in inverted papillomas. Positive staining was found in 17 of 19 inverted papillomas (89%). Immunoreactivity involved predominantly basal and parabasal cells and was either comparable or higher in inverted papillomas compared with adjacent mucosa. In 65% of immunoreactive inverted papillomas comparable staining results were seen between columnar (respiratory), transitional (cuboidal), and squamous epithelium. In 35% of p53 protein-positive inverted papillomas, enhanced immunoreactivity was observed in transitional (cuboidal) and squamous epithelium compared with columnar (respiratory) epithelium. Within these cases, immunoreactivity was either comparable or higher in squamous compared with transitional (cuboidal) epithelium. Conclusively, the expression of p53 protein is present in 89% of nondysplastic sinonasal inverted papillomas and also involves the adjacent, nonpapillomatous nasal mucosa. A tendency toward increasing p53 protein expression from nonpapillomatous nasal mucosa to inverted papilloma as well as along the metaplastic process from columnar (respiratory) to transitional (cuboidal) and finally squamous epithelium within inverted papillomas can be postulated.

Adult↗

PubMedDate not supplied

[Accessory adrenal cortex tissue in the placenta].

The first Description of heterotopie adrenocortical tissue within a placenta was made by Cox and Chavrier in 1980. By means of an orther case report we try to determine the period when corpora interrenalia accessoria are layed down in embryonic life.

Adrenal Cortex↗

PubMedDate not supplied

Monitoring of anticancer drug effects in vivo by serial DNA flow cytometry of oral carcinomas treated by intra-arterial 5-fluorouracil/cisplatin induction chemotherapy.

Thirty-one patients with squamous cell carcinomas of the oral cavity who underwent intra-arterial induction chemotherapy with 5-fluorouracil and cisplatin were analysed by DNA flow cytometry. Seven tumors consisted exclusively of diploid cells and 24 were characterized by the presence of an aneuploid tumor cell line. Response to chemotherapy as well as survival were significantly better in the diploid group. The cytotoxic effect of the treatment on aneuploid tumor cell populations was monitored in vivo by serial DNA flow cytometric measurements. Decreasing numbers of aneuploid cells were detected in all but two cases (92%); twelve (50%) showed a complete disappearance of the aberrant cell line at the end of chemotherapy. All non-responders showed persisting aneuploid tumor cells at the end of treatment. Even if response to chemotherapy was better in the group with a complete disappearance of the aneuploid cell line in the course of treatment, the survival outcome of these patients did not differ significantly from those who showed persistence of aneuploid tumor cells.

Aneuploidy↗