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Biomedical subjects

H Weidauer

Publications and source records attributed to H Weidauer.

At least 55 records · Page 3Linked to original sources
PubMed1992

[Decreased aspiration after extensive tumor surgical interventions in the area of the mouth cavity and pharynx by laryngeal suspension].

Lateral laryngeal suspension in combination with a cricopharyngeal myotomy represents a simple technique for prevention and/or treatment of chronic aspiration in patients during or after surgery for head and neck cancer. At the Department of Otolaryngology/Head and Neck Surgery of the University of Heidelberg this technique has been employed with satisfying results in 6 patients with large carcinomas of the oral cavity and pharynx. Lateral laryngeal suspension was not able to prevent--or if used secondarily--to eliminate aspiration completely in all patients. However, none of our patients experienced aspiration of saliva postoperatively. All were able to use a speech canula and some could even be fed orally.

Carcinoma, Squamous Cell↗
PubMed1992

[Laryngeal cancer and occupation--results of the Heidelberg laryngeal cancer study].

We conducted a case-control study of squamous cell carcinoma of the larynx referred to occupational factors in 164 patients compared with 656 controls adjusted for sex, age and area of residence, using a 1-to-4 matched design. Most of the cancer patients (92%) were blue collar workers. Only 8% of the cancer patients had attended technical college, college or university, compared with 31.3% of the control subjects. After adjustment for alcohol and tobacco consumption we found an increased relative risk of laryngeal cancer in subjects chronically exposed to cement dust, pine wood dust and coal-tar products. The risk associated with cement dust and coal-tar products was predominantly related to supraglottic cancer (RR = 1.88, CI = 0.8-4.3, RR = 6.11, CI = 1.7-21.6), respectively, after adjustment for tobacco and alcohol use. The risk associated with pine wood dust was related predominantly to glottic cancer (RR = 3.18, CI = 1.1-9.0) after adjustment for tobacco and alcohol use.

Carcinoma, Squamous Cell↗
PubMed1991

[Significance of hyponatremia in patients with oropharyngeal tumors].

We observed 29 patients with hyponatremia associated with oropharyngeal carcinoma. In 19/29 the hyponatremia was attributable to a decreased effective arterial blood volume whereas in the remainder (10/29) the presence of SIADH could be demonstrated. These etiologies of hyponatremia were best differentiated by the plasma urea concentration (less than 30 mg/dl in SIADH), urate concentration (less than 4,0 mg/dl in SIADH) and creatinine concentration (less than 0,9 mg/dl in SIADH). Furthermore, SIADH patients had a spontaneous natriuresis. The mainstay of therapy in either form of hyponatremia is fluid restriction (less than 1 l/d).

Carcinoma, Squamous Cell↗
PubMed1991

Ototoxicity of vancomycin: an experimental study in guinea pigs.

Vancomycin (V)-a polypeptide antibiotic-is the drug of choice in severe infections with multiresistant staphylococcus spp. Due to the multimorbidity of the patients receiving V, the interactions with known ototoxic agents and the lack of an audiometric documentation, earlier clinical reports of V-associated hearing loss must be carefully interpreted. To elucidate this topic, a controlled animal study considering nonspecific effects was performed. 40 albino guinea pigs with positive Preyer's reflex and normal hearing were used. The hearing function was controlled by means of brainstem auditory evoked potentials before and after intraperitoneal administration of V (75, 150, 300 mg/kg b.w. for 11-17 days), gentamicin (60 mg/kg b.w. for 26 days), neomycin (100 mg/kg b.w. for 17 days) and sodium chloride solution. The cochleas were dissected for hair cell counting by the surface preparation technique. Additionally, the serum concentrations of V were measured. As a result there was no significant difference in hearing loss between the controls and the animals treated with 75 and 150 mg V; toxic doses of 300 mg V led to a certain threshold elevation after click stimuli, but not after trapezoid stimuli of 1, 4 and 8 kHz. On the other hand, the aminoglycosides as a positive control caused an obvious hearing loss after click and trapezoid stimuli, which was correlated to the amount of outer hair cell loss. Renal damage could be excluded by histological examination of the kidneys and estimation of creatinine in serum. Therefore, treatment with moderate doses of V comparable to clinical conditions does not exhibit a specific ototoxicity as compared to the aminoglycosides.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

The status of trypsin-like enzymes in squamous-cell carcinoma of the head and neck region.

The activity of two proteases associated with tumour cells was studied using frozen sections of squamous-cell carcinoma and fluorescent probes for the enzymes. Four fluorescent probes were used to define the enzymic status of guanidinobenzoatase on the surface of the squamous carcinoma cells. Each of four probes demonstrated the location of cells possessing inactive guanidinobenzoatase, whereas adjacent cells of the same tumour exhibited active enzyme. It was shown that the inactive form of the enzyme was an inhibitor-enzyme complex that could be dissociated. In contrast, all of the squamous carcinoma cells possessed active trypsin-like enzymes that were recognised by fluorescent aprotinin molecules. The observed variation in enzymic status of these two tumour-associated enzyme systems is discussed in the context of a possible biological control mechanism for cell migration.

Aminacrine↗
PubMed1990

[Occupation and cancer of the oral cavity, pharynx and larynx].

There is increasing evidence of an association between occupational factors and head and neck cancer. The present paper reviews the most relevant epidemiological studies published within the last 30 years. Generally these studies indicate an increased cancer risk for "blue collar workers" exposed to dust or inhaled organic and inorganic agents. Moreover, the increased risk of head and neck cancer in most studies persists after adjustment for alcohol and tobacco consumption. More detailed, clinically orientated studies are necessary to provide a better understanding of the role of occupational factors in head and neck cancer.

Carcinogens↗
PubMed1989

Activity of the proteolytic enzyme guanidinobenzoatase in human basal cell carcinoma.

Basal cell carcinomas exhibit a characteristic pattern of aggressive invasion from the basal layer of skin epithelial cells. These tumour cells possess an enzyme, guanidinobenzoatase (GB), which is known to be associated with cell migration. The enzyme is inhibited by a fluorescent probe, 9-aminoacridine, and this can be used to locate cells possessing active guanidinobenzoatase. All basal cell carcinoma cells in frozen sections were located by their ability to bind 9-aminoacridine. Extracts of most tissues were shown to contain inhibitors of the GB associated with basal cell carcinoma cells. Extracts of skin, however, failed to inhibit this tumour-associated GB. The significance of these results is discussed in terms of the pathophysiology of basal cell carcinomas.

Aminacrine↗
PubMed1989

Inhibition of trypsin-like enzymes on cells with rhodamine-aprotinin.

Aprotinin, a polypeptide inhibitor of trypsin-like enzymes, has been labelled with rhodamine. Rhodamine-aprotinin inhibits trypsin in free solution in an identical manner to aprotinin. Rhodamine-aprotinin binds to trypsin-like enzymes on cells in formaldehyde fixed wax embedded sections. This technique has been used to locate cells possessing trypsin-like enzymes by means of fluorescent microscopy. In the present study we have used this technique to locate tumour cells.

Animals↗
PubMed1988

Studies on the activity of a protease associated with cells at the advancing edge of human tumour masses in frozen sections.

A fluorescent probe has been employed to study the status of a tumour associated protease, guanidinobenzoatase, in frozen sections of human tumours obtained from the head and neck regions. The results indicate that in vivo a naturally occurring inhibitor of guanidinobenzoatase effectively controls the activity of this enzyme on the majority of cells in a tumour mass. This inhibitor can be artificially displaced by formaldehyde treatment of the frozen sections and this treatment reveals the extent of latent enzyme in the section. In the frozen sections it was noticed that at the advancing edges of the tumour mass, the tumour cells possessed uninhibited guanidinobenzoatase, an enzyme known to degrade the link peptide between cells and fibronectin. It was shown that a synthetic inhibitor of guanidinobenzoatase selectively inhibited the guanidinobenzoatase of the tumour cells at the advancing edge of the tumour mass. It is suggested that the guanidinobenzoatase on cells at the leading edge of the tumour mass plays an important role in the invasion of adjacent host tissue. This synthetic inhibitor of guanidinobenzoatase has no inhibitory action on other trypsin-like enzymes and might therefore be of value in limiting the growth of the tumour mass in vivo.

Aminoacridines↗
PubMed1988

[Mucous membrane manifestations in HIV infection].

We report the occurrence of mucous membrane manifestations in six patients with HIV-infections: Kaposi sarcomas of the hard palate, of the gingiva, of the larynx and of the glans penis, unusual spreading of condylomata acuminata, bowenoid papulosis, thrush and hairy leukoplakia.

Acquired Immunodeficiency Syndrome↗
PubMed1987

[Neuroendocrine carcinoma (Merkel cell tumor) in the head and neck area].

The neuroendocrine carcinoma of the skin has its histogenetic origin in Merkel cells and a preference in head and neck area in the seventh decade of life. The definitive diagnosis can be made with a combination of electron microscopy and immunohistochemistry. Merkel cell carcinoma is a primary cutaneous neoplasma and is rarely found on the lips or gingiva. Operation and radiation are the therapy of choice. The value of an additional antineoplastic chemotherapy in the treatment of Merkel cell carcinoma is still controversial. Although long survival times had been described in literature the occurrence of local relapses and metastases demands for frequent controls.

Aged↗
PubMed1986

Infection of the oral mucosa with defined types of human papillomaviruses.

Biopsies from 9 different oral papillomatous proliferations were analysed for human papilloma viral (HPV) sequences of types 1 to 19 and 21 to 26 by Southern blot analysis with 32p-labelled cellular DNA. HPV sequences were detected in 7 out of 9 biopsies obtained from individual patients. Of three cases with the clinical diagnosis focal hyperplasia Heck, two contained HPV-6 related sequences and one HPV 13. In addition, one tongue base papilloma contained HPV 11. A papilloma of the palate revealed HPV 11 sequences. HPV 6 could be demonstrated twice in the remaining 4 oral papillomatous proliferations. Two biopsies remained negative. The data shows that HPV DNA can be regularly demonstrated in oral papillomas.

Biopsy↗
PubMed1986

[Cytokeratin expression in normal and malignant tongue epithelium].

Patterns of cytokeratin expression in squamous cell carcinomas of the tongue were examined by two-dimensional gel electrophoresis of cytoskeletal proteins and by immunofluorescence microscopy using antibodies specific for certain cytokeratins. The results were compared with those obtained from normal tongue mucosa. All carcinomas examined synthesized large amounts of cytokeratins as well as of desmosomal proteins such as desmoplakin(s) but differed from the normal tissue by the specific cytokeratin pattern expressed and by their heterogeneity of expression, which in immunofluorescence microscopy resulted in patchy, staining patterns. In general, the carcinomas showed a reduction of the amount of certain cytokeratins such as Nos. 4 and 13 which are abundant in normal epithelium. On the other hand, some other cytokeratins were present in relatively increased proportions, and certain subtypes of lingual carcinomas revealed, in addition, significant levels of cytokeratins 8 and 19 which are commonly considered to be typical of simple epithelial cells and tumours derived therefrom. To explain the differences of cytokeratin patterns between these tumours and normal epithelium as well as between different forms of squamous cell carcinomas two hypotheses are discussed, i.e. clonal selection of certain cells present in the original epithelium, probably in the basal layer(s), and different pathways of differentiation in the cell progeny derived from the transformed cell(s) of origin. The heterogeneity of cytoskeletal protein patterns in different lingual carcinomas, which was also noted for oropharyngeal, hypopharyngeal and laryngeal carcinomas, is discussed in relation to different kinds of response to therapeutical treatment.

Carcinoma, Squamous Cell↗
PubMed1986

[Poorly differentiated laryngeal tumors. An electron microscopy analysis].

Poorly differentiated laryngeal carcinomas, which light microscopically are made up of anisomorphic nuclei, undifferentiated cytoplasm and hardly visible cell membranes, show electronmicroscopically a remarquable polymorphism. The tumor cells, which form solid or trabecular groups of different sizes often with poorly defined borderlines to the stroma, are subdivided according to their ultrastructural features in spinosa, secretory and stemcell types. Lymphocytes, plasmacells and reticular cells may show distinct focal proliferation or may be completely absent. In some cases, there was a transition between tumour tissue and metaplastic ciliated and glandular epithelium with concomitant reduction of normal glands. By comparison, besides hyperplastic and metaplastic squamous and ciliated epithelium, normal mucosal biopsies reveal invaginations of pseudostratified ciliated epithelium.

Actin Cytoskeleton↗
PubMed1986

[Perioperative respiratory problems in patients pretreated with bleomycin].

We examined the incidence of an acute respiratory insufficiency in a retrospective study in 100 patients with carcinomas in the head and neck region who had received cytostatic pretreatment with bleomycin. All patients had been ventilated intraoperatively with 28% to 33% oxygen under precise control of blood gas analysis. In 93% of the patients, there were no respiratory problems in the postoperative course. The total lethality was 7%. Extrapulmonary causes were most prominent in five patients. In one patient, pre-existing pulmonary silicosis was suspected to be the cause of the acute respiratory insufficiency. Only in one patient was the acute respiratory insufficiency refractory to therapy very probably attributable to the synergistic toxic effect of bleomycin and oxygen on the lung parenchyma, as postulated by Goldiner and verified later in animal experiments. On the basis of these results, we do not consider that it is justifiable to reduce categorically the inspiratory oxygen concentration to 21% to 25% oxygen in bleomycin-pretreated patients with tumours in the head and neck region, as recommended by Goldiner. Since the majority are elderly patients with pre-existing cardiopulmonary stress, we recommend moderately reduced oxygen concentrations of 28% to a maximum of 33%. Further recommendations to prevent an acute respiratory insufficiency by those patients are discussed.

Adult↗
PubMed1986

[Papilloma viruses in benign and malignant tumors of the mouth and upper respiratory tract].

A total of 113 benign and malignant tumours of the mouth and upper respiratory tract have been analysed for the presence of papilloma virus DNA. Thirty-four (63%) of 54 papillomatous lesions were found to contain such DNA. Seventy-two percent of the laryngeal papillomas contained HPV 6 or HPV 11 DNA, whereas the oral papillomatoses harboured HPV 6 (15.6%), HPV 11 (9.4%), HPV 7 (9.4%), HPV 13 (12.5%) and HPV 32 (9.4%) DNAs. The high number of HPV 7 DNA-positive lesions was unexpected. In most of the malignant tumours no papilloma-viral DNA was found, with the exception of 3 tongue-base carcinomas, and in a metastasis from one of the tumours, which contained HPV 16 (3 biopsies) and HPV 2 related sequences (1 biopsy).

Base Sequence↗
PubMed1986

[Immunohistologic analysis of chronic obstructive sialadenitis. I. Changes in the expression of antigens of the major histocompatibility complex].

In the course of electrolyte sialadenitis progressing towards obstructive sialadenitis, changes in the epithelial expression of antigens of the major histocompatibility complex (MHC) occur even before morphological alterations and inflammatory cells can be detected. Class I antigens are enhanced and induced, and Class II antigens are induced. These changes begin focally. Only the expression of HLA-A,B,C and -DR in acinar epithelium is linked to the close vicinity of lymphohistiocytic infiltrates. In later stages of the disease the foci tend to fuse and antigenic changes are pronounced in areas of fibrosclerosis and parenchymal atrophy. The altered MHC antigen expression induced by chronical saliva congestion probably represents an important part of the postulated "immunoreaction in the duct epithelium" supposedly giving rise to this type of immunosialadenitis.

Adult↗