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T Löning

Publications and source records attributed to T Löning.

At least 127 records · Page 7Linked to original sources
PubMed1988

Immunoblot analysis of immune response to Campylobacter pylori and its clinical associations.

Systemic immune response to Campylobacter pylori was detected by the immunoblot technique in serum samples from 200 patients, 129 blood donors, and 96 children. The results of the IgG immunoblot test showed excellent correlation with the detection of C pylori by culture and also with histopathological examination of the antrum, as well as with peptic ulcer disease. An IgA response also occurred and gave results comparable with those of the IgG immunoblot test, although on a quantitatively lower scale. The IgM immunoblots were of no help in the serodiagnosis of C pylori infection. The protein bands that seemed to be the most specific for C pylori and which were consistently observed in patients positive for C pylori were a 110 kilodalton and a 63 kilodalton band on the IgG immunoblot and an 89 kilodalton band on the IgA immunoblot. A 94 kilodalton and a 28 kilodalton band were also included in the evaluation. While immunoblot analysis may be used effectively for the serodiagnosis of C pylori infection and can distinguish between patients with normal antrum mucosa and those with gastritis, the test does not help to distinguish between those patients with antrum gastritis who subsequently develop peptic ulcers and those who do not.

Adolescent↗
PubMed1987

Human papillomavirus type 13 and focal epithelial hyperplasia of the oral mucosa: DNA hybridization on paraffin-embedded specimens.

16 cases of focal epithelial hyperplasia (Heck's disease) were studied for the presence of human papillomavirus DNA by means of nucleic acid hybridization. Hybridization was carried out in situ with biotin-labelled probes of HPV 1, 6, 11, 13, 16, and 18 DNA under stringent and non-stringent conditions. Under non-stringent conditions, 6 of 16 cases (38%) hybridized to a mixture of HPV 1, 6, 11, 16, and 18 DNA. When these probes were applied under stringent conditions, only one case could be shown to be weakly positive for HPV 6/11 DNA. Further stringent hybridizations, which were conducted with a HPV 13 probe on 12 of our 16 cases, revealed a positive result in 9 of 12 cases (75%). The results of our study strongly substantiate the concept that HPV 13 or a closely related HPV type is associated with lesions morphologically presenting as focal epithelial hyperplasia.

Adult↗
PubMed1987

In situ hybridization to detect Epstein-Barr virus DNA in oral tissues of HIV-infected patients.

Thirty biopsies of oral mucosal lesions and normal oral mucosa were obtained from 26 HIV-seropositive individuals and studied for virus infections with Epstein-Barr virus-specific DNA probes (EBV). In situ DNA hybridization was carried out on frozen and formalin-fixed, paraffin-embedded tissues. Specifically bound biotinylated virus probes were detected with the streptavidin-gold-silver technique and visualized by standard and interference reflection microscopy. In 9/30 biopsies, EBV DNA was clearly demonstrated in the upper two thirds of oral epithelia. This finding corresponded to peculiar cytopathic effects including ground glass nuclei, basophilic nuclear inclusions, and ballooning of the cytoplasm, which were concentrated in the upper two or three layers of the stratum spinosum. Cytopathic effects together with the demonstration of EBV DNA were demonstrated in seven cases of tongue mucosa, and two cases derived from the gingiva. When comparing clinical and pathological findings with DNA detection rates, we saw 5/9 hairy leukoplakias associated with EBV infections. Four positive cases (two samples from the tongue, two gingival specimens) had not been regarded as hairy leukoplakia clinically. EBV infection of the oral epithelium occurred in male homosexuals (7 cases) and in male/female intravenous drug abusers (2 cases). Among the nine EBV-positive cases, 2 patients were asymptomatic, 4 patients were grouped into the ARC-, and 3 individuals into the AIDS-category. We conclude that HIV-seropositive patients are particularly prone to develop productive EBV infections in oral epithelia. This infection most frequently appears at the lateral border of the tongue, but may also occur at other sites of the oral cavity, and may already exist in a preclinical stage prior to the development of oral white lesions (hairy leukoplakia).

AIDS-Related Complex↗
PubMed1987

Prognostic significance of Leu-M1 immunostaining in papillary carcinomas of the thyroid gland.

Leu-M1 antigen is a monocyte/granulocyte-related marker known to be consistently expressed in the Reed-Sternberg cells of patients with Hodgkin's disease. Recently, however, the presence of Leu-M1 has also been noted in tumour cells of a variety of non-haematopoietic neoplasms, most of them adenocarcinomas. The biological significance of this aberrant reaction has not been clarified. We have been able to demonstrate marked epithelial Leu-M1 immunoreactivity (greater than 15% tumour cells positively stained) in 24 out of 76 (32%) papillary carcinomas of the thyroid gland (PC). This phenomenon was more frequently observed among PCs at an advanced stage of disease (pT4 vs. pT1-3 and M1 vs M0 p less than 0.05). The degree of epithelial Leu-M1 positivity was also shown to be significantly correlated to the clinical course of PC. Irrespective of other morphological and clinical features, death resulting from cancer occurred 17 times more frequently among PCs with marked Leu-M1 positivity (8/24) when compared with tumours with only slight or absent immunoreactivity (1/52) (p less than 0.00005). These findings suggest that Leu-M1 immunostaining provides significant prognostic information for patients with papillary carcinoma of the thyroid gland.

Antigens, Differentiation↗
PubMed1987

Extent and diversity of inflammatory cell infiltrates in squamous cell carcinomas and basal cell epitheliomas of the head and neck.

Using monoclonal antibodies reactive with Langerhans' cells (LCs), macrophages, and T cell subpopulations, the density and proportions of cells of the immune system of the normal oral mucosa were determined immunohistochemically, and compared with findings in oral squamous cell carcinomas (SCC) and basal cell epitheliomas (BCE). In normal oral epithelia, the dominant cell type was the LC, positive for CD 1, and expressing HLA-DR antigens (DR+). Many intraepithelial cells were lymphocytes of the suppressor/cytotoxic phenotype (CD 8+), which was also the most prominent cell type in the normal mucosal stroma. Significant differences were observed for the content of CD 8-, OKM 1-, and CD 4-positive cells in the epithelium of normal oral mucosa, SCC, and BCE, and for the amount of CD 1-positive Langerhans cells in the connective tissue of the different groups of tissues. When CD 4/CD 8 ratios were calculated, differences between SCC and BCE became most evident. A CD 4/CD 8 ratio greater 0.5 was seen to be characteristic for BCE. Thus, in contrast to the striking preponderance of suppressor/cytotoxic lymphocytes (CD 8+) in SCC, BCE showed typically almost balanced numbers of suppressor/cytotoxic (CD 8+) and helper/inducer (CD 4+) lymphocytes. This finding further underlines the biological differences recognized between these most common neoplasias of the head and neck.

Adult↗
PubMed1987

HPV DNA detection in tumours of the head and neck: a comparative light microscopy and DNA hybridization study.

A series of 22 squamous cell carcinomas (4 cases grade 1; 11 cases grade 2; 7 cases grade 3) of the oral cavity (13 cases), (naso-)pharynx (5 cases) and larynx (4 cases) were studied by conventional light microscopy and filter (dot blot) hybridization for the detection of human papillomavirus (HPV) DNA. In 4 carcinomas, tumour-free tissue from the resection margins of the surgical sample was examined in addition to the tumour specimen. The same kind of investigation was carried out on 4 oral leukoplakias without dysplasia. All cases were thoroughly examined for HPV-associated cytopathic effects (koilocytosis). In all cases, material was obtained for DNA extraction followed by dot blot hybridization. DNA hybridization was carried out under stringent conditions with mixed probes of HPV 6/11 as well as HPV 16/18. Koilocytosis was observed in 10/22 carcinomas (45%, 4/4 G1 tumours, 6/11 G2 tumours, none out of 7 G3 tumours) and 3/4 leukoplakias. Koilocytosis always occurred at the tumour surface or the surface epithelium immediately adjacent to the tumour. HPV DNA was found in 8/22 carcinomas (36%, 2/4 G1 tumours, 5/11 G2 tumours, 1/7 G3 tumours). We observed HPV 16/18 infections in 3 cases and HPV 6/11 infection in 1 case. The other 4 cases were positive under relaxed conditions and, thus, could not be grouped into one of the examined types of HPV infections. In 4 carcinoma cases, tumour tissues and resection margins were examined. 3/4 cases showed concordant findings, i.e. in 2 cases tumour tissue and tumour-free mucosa (1-2 cm distant to the tumour) were positive for HPV, 1 case was negative in both samples. In 6/8 cases positive for HPV, HPV DNA detection corresponded to the observation of intensive koilocytosis. The leukoplakias were seen to harbour HPV DNA in 3 cases (1 case: HPV 6/11; 1 case: HPV 16/18; 1 case: positive under relaxed conditions). We did not observe HPV DNA in normal mucosal tissues. Our findings provide further evidence for the presence of HPV infections in tumours of the upper respiratory and digestive tract. Prospective studies now have to clarify the biological importance of HPV infections in this group of human cancer.

Adult↗
PubMed1987

[Detection of neuroblastoma cells in bone marrow by Southern blot and in situ hybridization using a NMYC DNA probe].

Recently an amplification of NMYC oncogene was discovered in stage III and stage IV as well as in stage II neuroblastoma cells. The extent of NMYC amplification is of prognostic value. A high expression of NMYC on mRNA level is correlated to the NMYC gene-amplification. We utilized the in situ-hybridization technique for the detection of NMYC-mRNA expression on cellular level, and the Southern Blot method for analysing the total genomic DNA. In three stage IV patients with overt neuroblastoma in bone marrow cells, NMYC gene-amplification as well as NMYC-mRNA were detected. Seven control bone marrows of patients with different heamatological diseases in different stages did not contain positive cells in our in situ-hybridization assay.

Base Sequence↗
PubMed1986

In situ hybridization for the detection of cytomegalovirus (CMV) infection. Application of biotinylated CMV-DNA probes on paraffin-embedded specimens.

Five autopsy cases of cytomegalovirus (CMV) infections were studied. Conventional light microscopy disclosed characteristic cytopathic effects in lungs, kidneys, and brain. In one case, electron microscopy was carried out and revealed typical herpesvirus particles. In situ hybridization was done with biotin-labeled CMV-DNA probes and an avidin-alkaline phosphatase detection system. 4/5 cases were observed to contain hybridizing cells in different organs. Intensity of hybridization was related to the severity of CMV infection, roughly estimated by counting cytomegalic cells. In addition to cytomegalic cells, a high number of normal-looking epithelial and mesenchymal cell types were positive. These latter cells showed nuclear hybridizations in contrast to cytomegalic cells which hybridized both within the nuclei and the cell bodies. This modified in situ hybridization procedure is a rapid and valuable tool for the detection and final demonstration of virus infection, and will be of particular help for the examination of paraffin-embedded specimens.

Adult↗
PubMed1986

Tissue polypeptide antigen and keratins in cervical neoplasia.

Antibodies against tissue polypeptide antigen (TPA) and keratins of high molecular weight (62-67 kD) were used to indicate different stages of cell differentiation. The immunohistochemical study was carried out by indirect immunofluorescence. In dysplasia, particularly in CIN grades II to III, TPA labeling comprised not only basal layer cells (as seen in normal mucosa) but more superficial layers as well. Expression of keratins of high molecular weight was reduced to small foci of keratinization and scattered dyskeratotic cells. In typical small cell anaplastic carcinoma in situ, TPA antibodies were observed to label all epithelial cell layers. There was no reactivity with antibodies against keratins of high molecular weight. In invasive cancer, TPA staining was closely related to the degree of maturation. Nonkeratinized tumor zones were entirely labeled by TPA antibodies, whereas keratinized tumor foci were negative for TPA except for peripheral tumor cell layers. In invasive cancer, keratins of high molecular weight were restricted to differentiated portions of the tumor. Our immunohistochemical findings support the present concepts of TPA (as a member of the heterogeneous keratin family) as an indicator of cell differentiation. Immunohistochemical demonstration of keratins of different molecular weight offers a method of assessing squamous differentiation at the cervical transformation zone and in cervical cancer and precancer.

Antigens, Neoplasm↗
PubMed1986

Detection of papillomavirus DNA in oral papillomas and carcinomas: application of in situ hybridization with biotinylated HPV 16 probes.

Four oral papillomas and 7 carcinomas were studied for the presence of HPV DNA by means of in situ hybridization. Hybridization was carried out with a HPV 16 probe labelled with biotin under different conditions (nick translation/photobiotin). Subsequently, a modified biotin-avidin-alkaline phosphatase procedure was used to visualize virus infected cells. Four/4 papillomas and 4/7 carcinomas were seen to contain HPV harbouring cells. Positive cells were located at intermediate and superficial cell layers in papillomas and in keratinized zones in carcinomas. Analogous results were found with nick translated and photobiotinylated probes. DNA-biotinylation in conjunction with the biotin-avidin-alkaline phosphatase detection system proved to be a sensitive, convenient and rapid modification of in situ hybridization.

Adolescent↗
PubMed1986

Detection of Campylobacter pyloridis in patients with antrum gastritis and peptic ulcers by culture, complement fixation test, and immunoblot.

The association of Campylobacter pyloridis with antrum gastritis and peptic ulcers was described. We investigated antral biopsies from 180 patients who underwent gastroscopy. By culture or Gram stain or both, we found overall 98 (54%) of them to be positive for C. pyloridis. In the various groups the following percentages were found to be positive: normal antral mucosa 3% (n = 30); moderate superficial antrum gastritis, 49% (n = 83); severe superficial antrum gastritis, 86% (n = 44); duodenal ulcer, 83% (n = 54); and gastric ulcer, 72% (n = 18). A serological screening that used a complement fixation test yielded the following results: highest rates of positive complement fixation titers were seen in patients with severe gastritis and those with duodenal ulcers, both with 79%; the lowest incidence was in a group of 20 blood donors, with 5%. Positive complement fixation titers in gastritis patients also correlated well with characteristic patterns on immunoglobulin G and A immunoblots, while there was no specific reactivity observed on immunoglobulin M immunoblots.

Antibodies, Bacterial↗
PubMed1986

Human papillomavirus (HPV) infection of cervical lesions detected by immunohistochemistry and in situ hybridization.

Ten cases of cervical dysplasia, 13 cases of carcinoma in situ, nine cases of invasive carcinoma, and six cases of normal tissue were investigated for the presence of papillomavirus group-specific antigens and for viral DNA. Viral proteins were identified with genus-specific papillomavirus antibodies. Cloned HPV 6, 11, and 16 DNA labeled with 3H were used for in situ hybridization followed by autoradiographic detection of hybridized probes. In cervical dysplasias, five of ten samples were positive for HPV antigens, two of four cases contained HPV DNA related to type 16, and nine of thirteen cases of carcinoma in situ showed the presence of HPV antigens. In five of seven lesions of carcinoma in situ, HPV DNA was detected (HPV 6 three cases, HPV 16 two cases). For invasive carcinomas, HPV antigens were not observed in four cases. In the other five cases investigated, HPV antibodies were reactive with few keratinocytes located either at the surface or in keratinized tumour zones. HPV DNA related to type 6 was seen in three of six cases. Six cases of normal cervical mucosa served as controls. In these cases, HPV antigens (five samples) or HPV DNA (one specimen) were not detected. The study underlines the value of recombinant DNA techniques for screening of HPV infections in cervical cancer and precancer; 50-70% of cervical lesions contained HPV-related DNA. These data were comparable to the percentage of cervical dysplasia and carcinoma in situ positive for HPV antigens.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Osteosarcomas and Ewing's sarcomas. Comparative immunocytochemical investigation of filamentous proteins and cell membrane determinants.

Primary malignant bone tumors, osteosarcomas (9 cases), and Ewing's sarcomas (10 cases) were examined for their reactivities with monoclonal and polyclonal antibodies against filamentous proteins and cell membrane determinants of the lymphoid and macrophage marker series. The reactivity of antibodies was studied on snap-frozen tissue probes by using a triple layer immunoperoxidase method. Osteosarcomas were positive for vimentin and, in part, for HLA-DR. Other types of intermediate-sized filaments were not detected in tumour cells. In a small number of cases (2/9) tumour cells were reactive with antibodies of the macrophage series (Leu M2). In Ewing's sarcomas, vimentin and HLA-DR was also demonstrated. It was particularly interesting that Leu M2 staining was found in the majority of cases (8/10). The staining pattern supports the assumption that this peculiar tumour is of mesenchymal (monocyte/macrophage) histogenesis. It was evident from the present study that, in primary osteogenic tumors, none of the examined tumour "markers" were as distinctive as they are for bone metastases. Nevertheless, the reactivity of Ewing's sarcoma cells with monoclonal antibodies of the Leu M2 type throws some highlights on the, as yet, obscure histogenesis of the neoplasm and may be of diagnostic value in conjunction with the known light and electron microscope features of the tumour.

Adolescent↗