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Biomedical subjects

W Lehmann

Publications and source records attributed to W Lehmann.

At least 91 records · Page 5Linked to original sources
PubMed1990

[A simple method for positioning and fixing the extremities during the radiotherapy of soft-tissue sarcomas].

The exact and reproducible radiotherapy of malignant tumours in the extremities is aided by reliable positioning of the involved limb. In our department individually-formed casts and circular fix up made of two-component polyurethane foam (NEOFRAKT, supplied by Schumacher, Krefeld, FRG) are used. These allow the maintenance of any bending, stretching and torsional positions. The fields to be applied are cut out of the casts, thus preventing any influence on the depth dose of the radiation involved.

Arm↗
PubMed1989

Effect of a mammary-derived growth inhibitor on the expression of the oncogenes c-fos, c-myc and c-ras.

A mammary-derived growth inhibitor (MDGI) inhibits the resumption of growth of stationary Ehrlich ascites carcinoma (EAC) cells in vitro. The present study shows that the resumption of growth is accompanied by a rapid increase of the steady state mRNA level of the proto-oncogenes c-fos, c-myc and c-ras, which is reduced by MDGI. EAC cells from the exponential growth phase insensitive to MDGI did not show a reduced RNA expression. The effect of MDGI represents a novel activity at the level of gene expression and suggests a link to exist between growth inhibition and the reduction of c-fos, c-myc and c-ras expression.

Animals↗
PubMed1989

[Adenocarcinoma of the paranasal sinuses: the situation in Switzerland and Geneva].

Eight cases of adenocarcinoma of the nasal cavity and sinuses were diagnosed in the ENT Clinic in Geneva during the period 1965-87. Five of these patients were carpenters and are the object of a detailed clinical and epidemiological analysis. From a review of the literature, it appears that the incidence of the disease in Switzerland is underestimated and that the professional risk for certain types of work is still unclear. Evaluation of the scope of this problem on a national scale and an increased awareness of the medial profession seem worthwhile.

Adenocarcinoma↗
PubMed1989

Laryngeal pathologies observed in microlaryngoscopy.

A retrospective analysis of 738 consecutive microlaryngoscopic procedures, performed in 655 patients at the Geneva Clinic of Otolaryngology, Head and Neck Surgery between 1981 and 1987, was undertaken. The 4 most frequent laryngeal pathologies were polyps, hyperplastic chronic laryngitis, Reinke's edema and laryngeal cancer accounting for 76.6% of all encountered pathologies. Of the sample studied, pathologies occurred more frequently in males than in females; however, certain pathologies were more common to one sex than to the other. In 15.3% of patients with benign lesions, multiple, coexisting laryngeal diseases were detected. In some instances, microlaryngoscopic and histological diagnoses were discordant.

Adolescent↗
PubMed1989

[The occurrence of adherence factors in Enterobacteriaceae from bacteriological meat examination and from food hygiene research material].

An account is given in this paper of the occurrence of 131 specific adherence factors (CFA 1a, CFA 1b, K88, K99) and 216 unspecific adherence factors (CT I) of Enterobacteriaceae strains from 917 bacteriological carcass inspection samples and of 23 or 87 identical strains recorded from 682 food hygiene samples. Identification was based on mannose-resistant and mannose-sensitive hemagglutination (MRHA and MSHA). Particular consideration was given to 3 aspects, occurrence of Escherichia coli adherence factors in bacteremic dissemination in bacteriological carcass inspection, parallel presence of additional virulence factors, and the hemagglutination spectrum of MSHA.

Animals↗
PubMed1989

[Indications and results of surgery of spontaneous intracerebral hematoma].

A report is given on the indication for the operation, the surgical procedure, and the results of the operation in 36 spontaneous intracerebral haematomas. The method of choice for the treatment was the osteoplastic trepanation with a removal of the haematoma. In two thirds of the cases a complete or essential retrogression of the preoperative neurological symptoms was achieved. On this basis, some fundamental statements for the therapy of spontaneous intracerebral haematomas are made.

Adolescent↗
PubMed1989

[The diagnosis of spontaneous intracerebral hemorrhage].

A report is given on the diagnosis of spontaneous intracerebral haemorrhages, which points art that because of possibly occurring surgical consequences every acute occurrence of cerebral symptoms should be cleared up as soon as possible. In this diagnosis the computer tomography is well to the fore, which enables not only the recognition of the haematoma itself and its extent, but in particular also positional relations to important cerebral structures. In a number of cases, however, a representation of the cerebral vessels is nevertheless necessary. As an exclusive diagnostic measure in case of an intracerebral haematoma the angiography does not reach the value of information of computer tomography.

Brain Neoplasms↗
PubMed1989

Response of different mammary epithelial cell lines to a mammary derived growth inhibitor (MDGI).

MDGI, a 14.5-KDa protein, is a chemically defined growth inhibitor, which we have purified from lactating bovine mammary gland and characterized biologically in a mouse Ehrlich ascites mammary tumour (EAT) short term suspension culture. It has now been tested for its inhibitory activity on proliferation of four malignant mammary epithelial cell lines of human and mouse origin and normal human mammary epithelial cells. In all experiments, cells were brought to quiescence by serum or growth factor deprivation. Using [3H]TdR pulse labelling the effect of MDGI was measured on the restimulation of proliferation after medium change. MaTu and T47 D, human malignant mammary epithelial cell lines, as well as the mouse malignant mammary epithelial cell line mMaCa 20177 could be inhibited, whereas the human malignant mammary epithelial cell line MCF7 showed a slight stimulation. MDGI showed no activity on the residual DNA synthesis of all cell lines after starvation. Normal human mammary epithelial cells (HMEC) of different passages could also be inhibited. Their responsiveness seemed to be dependent on the number of passages. Cells from high passages (10-14) showed a higher sensitivity, which is also about 10 times higher than that of the malignant cell lines. Furthermore, growth factors like insulin, epidermal growth factor (EGF) and fetal calf serum (FCS), known to be potent antagonists to the MDGI activity in the EAT and, in the case of insulin, also in the MaTu culture (shown in the present study), do not abolish the inhibitory activity of MDGI on HMEC cells. These results demonstrate that the inhibitory activity of MDGI is not exclusively restricted to EAT cells studied so far.

Animals↗
PubMed1988

Cancer of the larynx/hypopharynx, tobacco and alcohol: IARC international case-control study in Turin and Varese (Italy), Zaragoza and Navarra (Spain), Geneva (Switzerland) and Calvados (France).

A case-control study on larynx and hypopharynx cancer was carried out in 6 populations including the city of Turin and the province of Varese (Italy), the provinces of Navarra and Zaragoza (Spain), the canton of Geneva (Switzerland), and the département of Calvados (France). This report presents an analysis of the risk associated with alcohol and tobacco consumption based on 1,147 male cases and 3,057 male population controls. Special attention was given to the study of the risk at various sites of larynx and hypopharynx. The effect of tobacco is similar for all sites and the risk associated with ever smoking is on the order of 10. The risks from alcohol drinking depend on site. They are similar for epilarynx and hypopharynx (RR = 4.3, for more than 80 g/day) and lower for endolarynx (RR = 2.1, for more than 80 g/day). For all sites the risk decreases after quitting (RR = 0.3 after 10 years); exclusive use of filter cigarettes is protective (RR = 0.5 relative to smokers of plain cigarettes only) as is exclusive use of blond tobacco (RR = 0.5 relative to smokers of black tobacco only). Inhalation increases the risk of endolaryngeal cancer but not that of hypopharynx or epilarynx. The relative risks for joint exposure to alcohol and tobacco are consistent with a multiplicative model.

Adult↗
PubMed1988

Plastic material used to optimize radiotherapy of head and neck tumors and the mammary carcinoma.

In order to improve head and neck tumor therapy, face masks were developed. The physical and mechanical properties of 11 apparently suitable materials were tested using a phantom. According to our studies "HEXCELITE" (supplied by Medimex, Hamburg, F.R.G.) proved to be the best material. Plastic breast molds were made to optimize the dose distribution for radiation therapy with fast electrons of post-mastectomy breast tumors. Here too the mechanical and physical properties of nine different materials were tested. The most suitable of these proved to be the gel mat "PRIMAMED" (supplied by Schülke and Mayr, Norderstedt, F.R.G.). The two materials mentioned have been well tolerated by more than 200 patients.

Bandages↗
PubMed1988

[Pyolaryngocele].

This study presents two new observations of laryngopyocele. It is a very serious form of clinical emergency related to latent asphyxia necessitating immediate medical attention. The treatment of choice consists of an external approach with removal of the superior edge of the thyroid lamina in addition to endotracheal intubation or a tracheotomy.

Aged↗
PubMed1988

[A simple device for positioning and fixing the head in radiotherapy of brain tumors in frontal and lateral position].

In radiotherapy of cerebral tumors in the occipital, central, and parietal area it can be favourable to fix the patient's head in frontal or lateral position. It is true that this problem can be solved by manufacturing individual face masks of PVC with the vacuum deep-drawing method, but this method is very time- and cost-consuming. The present study suggests a simplified method using the thermoplastic polyester "Orfit". Such a mask provides a good immobilization and can be manufactured in 10 to 15 minutes without bothering much the patient. Simulation and computed tomography are not substantially affected by the material.

Brain Neoplasms↗
PubMed1987

Identification of a polypeptide growth inhibitor from bovine mammary gland. Sequence homology to fatty acid- and retinoid-binding proteins.

A polypeptide growth inhibitor purified from bovine mammary gland (mammary-derived growth inhibitor) has been shown to reversibly inhibit proliferation of mammary carcinoma cells at concentrations of about 10(-10) M. The carrier of inhibitory activity has been identified biochemically as an about 13-kDa polypeptide and chemically by elucidating the amino acid sequence. No homology to any of the hitherto structurally investigated growth inhibitors (transforming growth factor beta, interferons) has been observed. The data revealed extensive sequence homology of mammary-derived growth inhibitor to a family of low molecular mass hydrophobic ligand-binding proteins, among them a fatty acid-binding protein from rat heart, myelin P2, a differentiation associated protein in adipocytes (p422) and the cellular retinoic acid-binding protein. Interaction with as yet unknown hydrophobic ligands might play a functional role in the mechanism of growth inhibition excerted by mammary-derived growth inhibitor.

Animals↗
PubMed1987

Frequency and sites of distant metastases in head and neck squamous cell carcinoma. An analysis of 101 cases at autopsy.

One hundred one cases of squamous cell carcinoma of the upper respiratory and digestive tracts were analyzed for distant metastases. In all cases, autopsies were performed. Forty (40%) of the 101 patients had presented with one or more distant metastases. The most common sites of distant metastases were the lungs (70%), the liver (42%), and the bones (15%). There was a correlation between initial cervical lymph node involvement and development of distant metastases. In five cases of distant metastases, no tumor was found in the site of the primary lesion or in the cervical lymph nodes.

Adult↗
PubMed1987

A randomized study of methotrexate, bleomycin, hydroxyurea with versus without cisplatin in patients with previously untreated and recurrent squamous cell carcinoma of the head and neck.

The value of a combination of methotrexate, bleomycin and hydroxyurea with vs. without cisplatin was randomly examined in 62 evaluable patients with previously untreated (44 patients) and recurrent (18 patients) squamous cell carcinoma of the head and neck. Methotrexate (30 mg/m2) and bleomycin (15 mg) were given intravenously weekly, hydroxyurea (1000 mg/m2) per os 3 times per week for 4 weeks. Cisplatin (60 mg/m2) was added on Day 1 every month. A higher overall response rate was observed with the cisplatin-containing regimen (66%, included 17% complete) as compared with 27% (3% complete) with the 3-drug combination (P value 0.0025). The cisplatin-containing regimen was more active in both previously untreated patient group and in the group recurrent patients. Toxicity was more pronounced in the cisplatin regimen and necessitated frequently reduced drug dosages. No survival difference was observed between the treatment groups. Median survival in previously untreated patients was 16.2 months and 7.2 months in patients who failed conventional local treatment. It is concluded that a cisplatin-containing regimen is more effective in advanced head and neck carcinoma than the same combination without cisplatin.

Adult↗
PubMed1987

Altered growth control by natural growth inhibitors in the mutant HD33 substrain of the Ehrlich-Lettré ascites mammary carcinoma.

The mutant substrain HD33 of the Ehrlich-Lettré ascites mammary carcinoma (EAC) was found to be altered in its ability to respond to and to produce natural growth inhibitors. Cells of this substrain did not respond to (1) a highly purified growth inhibitor from bovine mammary gland, inhibiting the proliferation of two strains of the original EAC already at concentrations of 0.5-2.0 ng/ml, (2) inhibitory activities found in the ascites fluid of these sensitive strains and partially purified. However, from the ascites fluid of the mutant substrain an inhibitory activity was partially purified, which was inhibitory towards this substrain. It also inhibited the cells from an original strain, although less effectively. This new inhibitory activity is similar in its properties to that of the others investigated in that its mol. wt is between 10,000 and 50,000 D, it is heat labile and its activity can be overcome by insulin, epidermal growth factor and 2'-deoxycytidine, the dose-response curve levels off at 35-45% inhibition. The results demonstrate that the regulation of cell proliferation by endogenous (autocrine) inhibitors can be altered by mutagen treatment.

Animals↗