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Biomedical subjects

M Barten

Publications and source records attributed to M Barten.

At least 37 records · Page 2Linked to original sources
PubMed1994

Human papillomavirus DNA in oral squamous cell carcinomas and normal mucosa.

Human papillomavirus (HPV) infections in oral carcinomas and normal oral mucosa were studied by consensus primer screening and typing for HPV types 6/11, 16 and 18 DNA. After polymerase chain reaction (PCR) the DNA species of interest were identified by Southern blot hybridization with digoxigenin-labeled oligonucleotide probes. Frozen tissue and scrapings were equally suitable for HPV testing and yielded high HPV detection rates in carcinomas. By comparison, HPV analysis of paraffin-embedded material was much less efficient. HPV were demonstrated in 61.5% (16/26) of oral squamous cell carcinomas, high risk HPV 16 and 18 being the preferential types. The frequency of HPV detection in non-neoplastic mucosa of tumor patients decreased clearly with increasing distance from the tumor (range 26.9-3.8%) suggesting focal HPV infections. In contrast, normal buccal mucosa of a group of healthy volunteers contained HPV DNA only in 1% (1/97).

Adolescent↗
PubMed1994

[p53 alterations and HPV status in oral squamous cell carcinomas].

Immunohistochemical examination of p53 protein accumulation, analysis of the p53 gene using amplification of the exons 5-8 followed by TGGE, and PCR based HPV typing were carried out on 40 oral squamous cell carcinomas. 28 of 40 oral carcinomas (70%) contained DNA of the oncogenic HPV types 16 and 18. A p53 accumulation was present in 20 of 37 tumors (54%). Mutations of the p53 gene were detected in 15 of 39 carcinomas (38%). 15 of 20 oral carcinomas with abnormal p53 expression and 11/15 tumors with mutations of the p53 gene were HPV positive. Our results demonstrate a frequent occurrence of p53 abnormalities in HPV positive oral squamous cell carcinomas. This pattern is divergent from HPV related genital carcinomas and could reflect differences in the etiology of squamous cell carcinomas of different sites.

Biopsy↗
PubMed1992

[Cytopathology of the breast. 2. Puncture cytology].

The fine needle aspiration cytology of the breast is the only way for the morphological examination of suspicious palpable lesions without surgical procedure. The cytological examination is able to produce clinical relevant results on the basis of typical microscopical pictures especially in breast carcinoma, fibroadenoma, and cysts. However it must be taken into account that not all breast tumors can be detected by fine needle aspiration cytology. Therefore negative and doubtful results have to be interpreted in connection with clinical and mammographic findings. An essential condition for good results is an effective punction technique to obtain representative probes of cell material. In case punction and cytological examination are not performed by the same investigator there is the risk that an inadequate punction technique is not noticed and leads to unsatisfactory cytological results. In connection with clinical and mammographic examinations the fine needle aspiration cytology can be used as alternative diagnostic way and replace the conventional breast tumor diagnostic procedure by surgical biopsy and frozen section, if the necessary requirements are fulfilled. This includes a high standard of clinical, mammographic and cytological examinations and a critical summarizing interpretation of the examination results.

Adenofibroma↗
PubMed1991

[Cytopathology of the breast. 1. Secretion and nipple cytology].

Cytological examinations of breast secretions, nipple smears and breast fine needle aspirates can establish important diagnostic findings provided that technical conditions and methodical advantages and disadvantages are taken into consideration. The first part of the paper is dealing with clinically relevant aspects of secretion and nipple cytology. These simple examinations are applicable by every gynaecologist. The source of cell material is the spontaneous exfoliation, which should be increased in nipple smears by additional procedures. Diagnostic findings of secretion cytology can be obtained in breast cancer, duct papilloma, cystic fibrosis, and inflammatory lesions. The value of secretion cytology for breast cancer detection is limited, because pathological secretion is only induced in a small number of patients. Cytological examinations of nipple lesions are useful especially in the presence of Paget's disease and other tumors of the nipple. Limitations are caused by difficulties in cell sampling. Easy practicability and little alteration of the patient are the major advantages of the secretion and nipple cytology, which stands opposite a limited sensitivity as disadvantage.

Biopsy, Needle↗
PubMed1990

[Colposcopic, cyto- and histologic signs of papilloma virus infection in precancerous and early stages of cervix cancer].

Basis of present study are examinations in 100 women with colposcopic and/or cytologic abnormalities suspect of preinvasive or early invasive carcinoma of the uterine cervix. We found 76 colposcopic abnormal findings in 100 women examined. In 36 women there was a colposcopic suspicion on a papilloma virus infection, in 32 cases combined with abnormal colposcopic findings. All 100 patients had cytologic smears group III and/or IV according to Papanicolaou. In 71 women cytologic signs of a papilloma virus infection was detected in the cervical smears. We found histologic signs of a papilloma virus infection in 69 cases in the specimen of biopsy, conization or hysterectomy (5 times condylomata acuminata, 53 times flat condylomata and 11 times inverted condylomata). Preinvasive respectively invasive and papillomavirus caused lesions of the cervix are coexisting in 59 cases. Our examination demonstrates that also in GDR in about 70 per cent of the precancerous or invasive cervical lesions signs of an infection with human papilloma viruses are present histologically and/or cytologically.

Biopsy↗
PubMed1990

[Gangliocytic paraganglioma of the duodenum. Case report with immunocytochemical characterization].

Described in this paper are histological, electron-microscopic, and immunocytochemical findings recorded from a duodenal gangliocytic paraganglioma in a 21-year old man. The sessile polypoid tumor consisted of epithelial cells, neuroid spindle cells, and gangliocytic elements. Neurosecretory granules were detected by electron-microscopy in the epithelial cells. The neuroid spindle cells exhibited the ultrastructural feature of Schwann cells. The tumor was immunocytochemically characterized by the S-100-reactivity of the spindle cells and numerous PP-reactive epithelial cells. Gangliocytic paragangliomas of the duodenum are of benign behaviour and should be removed by local excision.

Adult↗
PubMed1989

[Clinical aspects, diagnosis and therapy of cancer of Vater's ampulla].

The carcinoma of the papilla occupies a special position among the periampullary carcinomas by its favourable prognosis. Responsible for this are the early appearance of symptoms due to the close neighbourhood to the common bile duct and the restriction of the metastasation to the first stage of lymphatic nodes in the majority of cases. Symptoms are jaundice, epigastric pain and decrease of weight. In the carcinoma of the papilla the duodenoscopy with biopsy and ERCP is the method of choice. The reliability of the biopsy is larger, when it is performed after an endoscopic sphincterotomy. For the delimitation of the carcinoma of the papilla against other causes can further be used the hypotensive duodenography, the abdominal computerd tomography, the sonography and the PTC. A curative treatment is possible only surgically. On account of the better long-term results the partial duodenopancreatectomy is to be preferred to the local exstirpation of the papilla. Endoscopic drainages of the biliary tract carried out preoperatively may reduce the lethality of operations. A palliative drainage of the biliary tract on the endoscopic or percutaneous transhepatic way as well as the endoscopic sphincterotomy may improve the patients' quality of life and prolong the survival time, when there are non-resectable tumours or a general inoperability.

Ampulla of Vater↗
PubMed1989

[Carcinoid tumor with cystic liver metastases].

Generally metastases of carcinoid tumours are pseudocystic in nearly 10% of the patients. In our case the guiding diagnostic importance of sonography and computed tomography could be proved. Results have to be completed by histologic findings and hormonal analysis (serotonin, 5-hydroxyindol acetic acid). - Morphological signs especially of the new imaging techniques are often a supposition for the modern therapy, e.g. the application of serotonin antagonists, local perfusion of cytostatic substances and if possible transplantation of the liver.

Angiography↗
PubMed1989

[Comparison of fine needle aspiration cytology and histology in hepatocellular carcinoma and in liver metastasis].

The cytological findings in fine needle aspiration biopsies of 5 hepatocellular carcinomas and 9 secondary liver tumours were compared with the histological findings in autopsy or surgical material. Definite diagnosis of malignancy was made in all cases. Similarity with liver cells, arrangement of the tumor cells corresponding to the different histological types of hepatocellular carcinoma, and the presence of bile pigment characterize the cytological picture of the hepatocellular carcinoma. Pleomorphic tumour cells and prominent nucleoli are other typical cytological findings. Liver metastasis were correctly typed in nearly all cases by the cytological examinations. The attempt to suggest the primary site is more difficult, but possible in some cases.

Biopsy, Needle↗
PubMed1989

[The incidence of borderline and pathologic findings in young females within the scope of gynecologic-cytologic screening studies].

The frequency of Pap III-V findings in cytological screening examinations in Rostock-City was estimated for the age groups 16-20, 21-25 and 26-30 years. Two 3-year periods (1972-1974 and 1981-1983) were compared. A significant 9-fold increase of cytological results of Pap groups III-V was found during this time. Possible causes of this changing pattern, especially papillomavirus infections were discussed. In the age group 26-30 years there was the highest progression rate with almost 10%, in contrast to 1% in the age group 16-20 years. In the three investigated age groups a regression rate of 46% and a persistence rate of 38% were found. The results underline the increasing importance of gynecocytological screening examinations in young women.

Adolescent↗
PubMed1988

[Characterization of experimentally induced malignant gastrointestinal tumors of rats using DNA-cytophotometry and karyometry].

The average relative DNA-content, the status of ploidy, the area of the nucleus, the compactness of chromatin and the variability of the shape of the nucleus were determined in 33 experimental induced malignant neoplasms and 5 benign lesions of gastric and intestinal mucosa of rats. The results were compared with diploid controls and divided into 3 types of DNA-histograms. Normal and malignant cells differed significantly in their DNA-content, in the area of the nucleus and in the percentage of hypertetraploid cells. 27 tumors belonged to the aneuploid type of histogram. The dignity was not clear in 6 cases. Diploid carcinomas did not occur. The DNA-cytophotometry gave the decisive hint to diagnosis of malignancy in 8 carcinomas. The various types of tumors differed not in the determined parameters. The problem of differential diagnosis between benign lesions with preneoplastic potential and malignant tumors is discussed.

Adenocarcinoma↗
PubMed1987

The effects of different MNNG (N-methyl-N'-nitro-N-nitrosoguanidine)-doses on the stomach and the upper small intestine of the rat. II. The frequency of intestinal metaplasia.

N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was given to 3 groups of male Wistar rats in different doses of 25 micrograms/ml, 50 micrograms/ml and 100 micrograms/ml with their drinking water for 32 weeks. After 50 weeks the antrum region of the stomach was investigated by serial sections. All animals showed tubules with metaplastic intestinal epithelium. The different values of metaplastic glands in the antrum region of the stomach were 187 (25 micrograms MNNG), 76 (50 micrograms MNNG) and 51 (100 micrograms MNNG). They indicate an inverse relationship of the frequency of intestinal metaplasia and the MNNG dose. As opposed to this dose-response pattern, cytotoxic alterations, regenerative hyperplastic lesions and tumours of the stomach are more frequent after medium of high MNNG doses. It is therefore suggested that the induction of intestinal metaplasia is a specific effect of the carcinogen mainly in the low dose range.

Animals↗
PubMed1987

The effects of different MNNG (N-methyl-N'-nitro-N-nitrosoguanidine) doses on the stomach and the upper small intestine of the rat. I. The frequency and histopathology of the induced tumours.

N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was given to 3 groups of rats with the drinking water for 32 weeks in different doses: 25, 50 and 100 micrograms/ml. After 50 weeks the induced tumours of the stomach and the upper small intestine were investigated. Most tumours were well differentiated adenocarcinomas or adenomatous-hyperplastic lesions with focal adenocarcinoma. After low MNNG-concentration (25 micrograms/ml) only adenomatous hyperplastic lesions with focal adenocarcinoma were found. A tumour development in connection with intestinal metaplasia was detectable exclusively in two rats of the group receiving 50 micrograms MNNG/ml. The frequency of gastric tumours shows a relatively low peak (3.3 tumours/10 animals) after administering a medium MNNG-concentration (50 micrograms/ml) and a little decrease of the frequency after higher MNNG-concentration, as opposed to the approximately linear dose-related increase of the tumour frequency in the upper small intestine. The highest tumour induction rate was found in the upper small intestine after 100 micrograms MNNG/ml (5.6 tumours/10 rats). It can be concluded that the mucosa of the upper small intestine possesses a greater susceptibility to the carcinogenic effect of MNNG than the glandular stomach of the rat.

Adenocarcinoma↗
PubMed1987

Diffuse gastric antral vascular ectasia: cause of chronic gastrointestinal blood loss.

In a patient with long-standing iron deficiency anemia, diffuse gastric antral vascular ectasia was found endoscopically. Diagnostic problems were the misinterpretation of the macroscopic finding as hemorrhagic inflammation and the microscopic confirmation of the diagnosis from small biopsy particles. Resection of the antrum resulted in a persistent normalization of hematologic parameters. Focal ischemia due to microthrombi in mucosal vessels might be the cause of the tendency of this vascular malformation to bleed.

Adult↗
PubMed1986

Endocrine cells in adenocarcinomas and their prestages in the glandular stomach and duodenum of rats after MNNG administration. Histochemical, electron microscopical and radioimmunological studies.

Tumours of the glandular stomach and upper small intestine were induced in rats by oral administration of MNNG. In most cases the lesions were identified histologically as adenocarcinomas and their prestages, such as polypeous and downward growing adenomatous hyperplasias. Out of 48 adenomatous hyperplasias and adenocarcinomas of the stomach and 24 well differentiated adenocarcinomas of the small intestine, we observed argyrophilic cells in nearly the half of the cases. Endocrine cells were also identified by electron microscopy. The frequency of endocrine cells was reduced with decreasing degree of tissue differentiation. In poorly differentiated carcinomas, including signet ring cell carcinomas, no argyrophilic cells were found. Out of 10 adenomatous hyperplasias and tumours of the stomach investigated immunohistochemically, 5 cases showed gastrin producing cells. Most of these animals were radioimmunologically characterized by strongly elevated serum gastrin levels. Derivation and potential relevance of the endocrine cells in tumours are discussed.

Adenocarcinoma↗
PubMed1986

[Comparative cytophotometric and cytomorphometric studies of concave cells and atypical squamous epithelial cells of the cervix uteri].

Cytologic slides from 11 women with clinical, cytological and histological signs of a papillomavirus infection of the cervix uteri are investigated by cytophotometry and cytomorphometry. The mean values of DNA content, chromatin density, nuclear area and nuclear circumference of koilocytes were notably higher than for atypical or normal squamous cells. In those patients with concurrent cervical intraepithelial neoplasia the DNA content of koilocytes was inversely related to the degree of atypia. Squamous cells with HPV-induced lesions can be characterized by cytophotometry and cytomorphometry as a distinct cell population forming a continuum with the preneoplastic epithelium.

Cell Nucleus↗
PubMed1983

[The stimulating effect of gastrin on the proliferation of gastric fundus mucosa].

Many gastrointestinal hormones have a stimulating action on the proliferation and growth of stomach and intestinal mucosa and on pancreas. This so-called trophic action was investigated most intensive on gastrin. We reproduced this effect autoradiographically by 3H-thymidine incorporation on the stomach corpus mucosa of rats. The animals had increased serum gastrin levels by partial stomach corpus resection that increased the endogenous serum gastrin level. The proliferation stimulating action of gastrin is also detectable at chronic oral application of N-Methyl-N'-nitroso-N-nitroguanidine for induction of stomach and intestinal tumors simultaneously to pentagastrin administration or partial stomach resection in the intact, tumor free oxyntic mucosa of stomach.

Animals↗