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B Drettner

Publications and source records attributed to B Drettner.

At least 19 recordsLinked to original sources
PubMed1995

N-nitrosodimethylamine and 7-methylguanine DNA adducts in tissues of rats fed Chinese salted fish.

Previous studies have demonstrated that rats fed Chinese salted fish developed carcinomas of the nasopharynx and nasal cavity. In the present work the contents of nitrosamines in salted fish from the city of Guangzhou, southern China, and the contents of nitrosamines and possible nitrosamine-induced DNA adducts in organs of rats fed the fish were analysed. Similar levels of N-nitrosodimethylamine (NDMA) were detected in tough and soft salted fish. The NDMA content in steamed fish was higher than in raw fish. In vitro incubation of salted fish with gastric juice significantly increased the level of NDMA. NDMA was found in liver and kidney from rats fed salted fish for 2 years, but no dose-dependence was found between salted fish treatment and NDMA content. The level of 7-methylguanine in rat liver DNA was found to be slightly higher than in DNA from nasopharynx. However, there were no significant differences in the level of 7-methylguanine in DNA samples from rats fed salted fish and rats fed standard diet.

Animals↗
PubMed1994

Basic experimental studies of ostial patency and local metabolic environment of the maxillary sinus.

Experimental studies of human maxillary sinus gas exchange show that there is a balance between inflow of air through the maxillary ostium and local consumption as long as the functional size of the ostium is at least 5 mm2. Maxillary sinus mucosal blood flow is 30-40 ml/100 g tissue per minute, as measured in plethysmographic studies. This blood flow can bind and transport only half of the absorbed oxygen, the rest is consumed. Experimental histo- and biochemical studies of sinusitis show anaerobic mucosal metabolism with shortage of energy supply due to inadequate oxygen supply. There is no decrease in oxidative enzyme capacity of the mucosal epithelium. Analysis of organic acids in purulent secretion indicates that the high lactate and CO2 concentration found is mainly the result of leucocyte glycolysis with local lactic acidosis. Both ostial occlusion and the initiation of bacterial growth in serous sinusitis may be secondary to an initial inflammatory response, resulting in local tissue pathology and swelling of the ostiomeatal complex, as well as creating the appropriate redox potential for further bacterial growth in the secretions.

Humans↗
PubMed1994

Induction of nasal and nasopharyngeal tumours in Sprague-Dawley rats fed with Chinese salted fish.

Epidemiological studies have implied that Chinese salted fish is a human nasopharyngeal carcinogen. In the present study, 162 Sprague-Dawley rats were randomly assigned to one of four experimental groups. Rats in groups 1 (n = 41) and 3 (n = 40) were exposed to salted fish from birth through the breast feeding period by giving the maternal rats a diet containing 10% and 5% salted fish, respectively, later feeding the rats with pellets containing 10% and 5% of salted fish respectively. In group 2, the rats (n = 41) were given pellets containing 10% of salted fish from 6 weeks of age. Rats in group 4 (n = 40), serving as controls, were only given ordinary pellets. Three rats had nasopharyngeal tumours, 2 from group 1 had a poorly differentiated carcinoma and a squamous cell carcinoma. One rat from group 2 had a squamous cell carcinoma. Four rats had nasal tumours, one fibrosarcoma and one adenocarcinoma were found in rats from group 1. One rhabdomyosarcoma was found in group 2, and one soft tissue sarcoma was found in a rat in group 3. No nasal or nasopharyngeal tumours appeared in the control group. The difference in the occurrence of malignant nasal and nasopharyngeal tumours among the four experimental groups was statistically significant (one tailed p for trend = 0.041). The frequency of tumours appearing in other organs such as the breast, kidney, lung, liver and brain was not significantly different between the salted fish treated groups and the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1994

Epstein-Barr virus infection, salted fish and nasopharyngeal carcinoma. A case-control study in southern China.

Two hundred and five histologically confirmed cases of nasopharyngeal carcinoma (NPC) in southern China, and an equal number of matched controls, were investigated for their dietary habits, occupational exposure, use of tobacco and alcohol, history of relatives with NPC, and IgA against Epstein-Barr virus (EBV) capsid antigen (IgA/VCA). Positive IgA/VCA and intake of salted fish were associated with a strong excess risk of NPC. The association persisted after adjustment for other factors. The combination of salted fish and EBV was strongly associated with NPC, and more so than EBV or salted fish per se. Multivariate analyses showed that IgA/VCA was the most important predictor of NPC, and salted fish the second most important. These results suggest that EBV has a strong effect on the development of NPC. The exclusion of EBV and genetic factors in earlier epidemiological studies may have resulted in an overestimation of salted fish as important etiological factor causing NPC.

Adult↗
PubMed1993

Studies on etiological factors of nasopharyngeal carcinoma.

A case-control study of nasopharyngeal carcinoma (NPC) was performed in Guangzhou, southern China in 1987 to 1989. We investigated 205 cases and an equal number of matched controls. Epstein-Barr virus (EBV) infection with positive IgA against viral capsid antigen (VCA-IgA) was shown to be the most important predictor in NPC. Consumption of salted fish was also strongly associated with NPC but not to the same extent as EBV. In order to investigate the possible carcinogenic effect of salted fish, Sprague-Dawley rats were given a diet containing salted fish for 2 years. Three rats with nasal and 3 with nasopharyngeal tumors were found in the experimental groups of 122 rats but none in the control group. Nitrosodimethylamine (NDMA) was found in kidney and liver but not in urine in the rats fed with salted fish. In a non-tumorigenic human keratinocyte line, RHEK-1, transfection of EBV latent membrane protein (EBV-LMP, originated from NPC cell line) induced alterations of morphology and immunophenotype. The LMP expressing sublines showed higher proliferative capacity and lower differentiation in vitro and some of the sublines produced tumors in SCID mice. When cultured in media containing salted fish extract in vitro parental RHEK-1 cells died after 12 weeks. In contrast, LMP expressing sublines survived indicating that exposure to some chemical compounds in salted fish and expression of EBV-gene may be of importance for the transformation of epithelial cells and thus for the pathogenesis of NPC.

Animals↗
PubMed1989

Experimentally induced sinusitis: the importance of vasomotor regulation.

An acute pneumococcal maxillary sinusitis was induced in New Zealand white rabbits by unilateral obstruction of the sinus ostium and then injecting 10(8) Streptococcus pneumoniae into the sinus. After subjecting this bacterial strain to one animal passage, the bacteria were reisolated in nine of ten infected maxillary sinuses. All rabbits developed a unilateral purulent sinusitis, while a non-purulent sinusitis could be induced by occlusion only of the maxillary ostium. By using a non-diffusable tracer, microspheres labelled with Sn113, blood flow measurements were performed on these sinuses. These studies showed that the blood flow of the infected sinuses was significantly higher than on the control side. However, in chronic sinusitis (with a blocked ostium), the blood flow did not differ significantly from that on the control side. Biochemical studies in the animals with purulent sinusitis demonstrated that lactate concentration in the mucosa was significantly higher as compared to the control side. The glucose concentration was significantly lower in the mucosa of the infected side, as was the ATP content of the sinus mucosa in purulent sinusitis. These results indicate an increased glycolysis as well as a relative energy depletion in the sinus mucosa in purulent sinusitis, which could result in an impaired epithelial function.

Animals↗
PubMed1988

Therapeutical aspects of sinusitis in relation to pathogenesis.

Modern aspects of the pathophysiology of sinusitis have given further evidence of the importance of ventilation and drainage as therapeutical procedures. A simple therapeutical method for implantation of a tube in the maxillary sinus for treatment of acute sinusitis is presented.

Anti-Bacterial Agents↗
PubMed1985

The effect of ipratropium bromide (Atrovent) on the air conditioning capacity of the nose.

The air conditioning capacity of the nose was assessed by a method which permits measurements in both nasal cavities without blockage of the passage between the nasopharynx and oropharynx. By this method the degree of warming of the air and its humidification during the passage through the nasal cavity can be calculated. The effect of intranasal application of ipratropium bromide (Atrovent) on the air conditioning capacity of the nasal mucosa was evaluated in a group of normal subjects and a group of patients with vasomotor rhinitis. In this short term trial Atrovent was found not to have any effect on this capacity.

Adult↗
PubMed1983

Quantitative measurements of radioactive isotopes in human nasal secretion.

Four patients receiving an intravenous injection of 99mTc-pertechnetate were investigated concerning transfer of the radioisotope to the nasal secretion. The concentration of isotope in nasal secretion was in all patients found to be approximately 10 times higher than in blood. The results suggest an active transport mechanism in the glandular elements of the nasal mucosa and that they are important as source of nasal secretion during normal conditions.

Adult↗
PubMed1983

Follow-up of patients with hereditary hemorrhagic telangiectasia in the nose, with special reference to septal dermoplasty.

Seventeen patients treated for recurrent epistaxis due to Osler's disease in the nose were followed up 6 months - 19 years after treatment. A written questionnaire was answered by 13 of the 14 patients surviving at follow-up. They had undergone either septal dermoplasty, or irradiation with 1200--1400 rad on both sides of the nose, or both kinds of treatment. All patients were satisfied with their treatment. The amount of nose-bleeding was reduced in all but one of the surgically treated patients, and the frequency was reduced in nine of the 13 patients. Nasal crusts, often causing nasal obstruction, were a problem, at least shortly after operation. Pathological vessels were found within the skin graft at secondary operation in one patient, showing that telangiectasia can develop in the graft area and cause recurrences of the epistaxis, sometimes necessitating further operations.

Adult↗