Biomedical subjects

K Wallenius

Publications and source records attributed to K Wallenius.

At least 37 records · Page 2Linked to original sources

PubMed1979

Zinc and copper levels in whole blood and plasma from patients with squamous cell carcinomas of head and neck.

Zinc in plasma and whole blood from 13 patients with squamous cell carcinoma of the head and neck was significantly decreased, and the copper:zinc ratio in the plasma was significantly higher than in healthy controls. The plasma zinc was significantly lower in patients who did not respond to therapy and who died within 12 months than in those who responded to therapy and had a remission within 12--15 months. In patients responding to therapy and alive after 12--15 months, zinc in the plasma and whole blood and the copper:zinc ratio became normal. These results suggest a potential screening and predicting value of zinc in the plasma and whole blood and the copper:zinc ratio in squamous cell carcinoma of the head and neck.

Adult↗

PubMed1979

Effect of different levels of dietary zinc on development of chemically induced oral cancer in rats.

Four-week-old female rats distributed among three experimental groups were fed a 0.23 (zinc-deficient), 0.77 (zinc-adequate) or 3.06 (zinc-supplemented) mmol zinc/kg diet and oral cancer was induced by repeated application of the water-soluble carcinogen 4-nitroquinoline N-oxide (4NQO) to the palatal mucosa. The clinical development of oral cancer differed significantly among the three groups (P less than 0.05). In rats fed the zinc-supplemented diet, the macroscopic oral cancer appeared early and the survival time was shorter than in either of the other groups. It was concluded that a zinc-supplemented diet accelerates, and a zinc-deficient diet retards the development of chemically induced oral cancer in rats.

4-Nitroquinoline-1-oxide↗

PubMed1979

Influence of zinc on onset and progression of oral carcinogenesis in rats.

Three-week-old female rats were fed 0.09 (zinc-deficient), 0.77 (zinc-adequate) or 3.98 (zinc-supplemented) mmol zinc/kg diet in three experimental groups and the palatal mucosa was painted with the water-soluble carcinogen 4-nitroquinoline N-oxide (4NQO) three times a week for 20 weeks. The zinc-supplemented diet seemed to retard the induction of carcinogenesis, whereas a low-zinc diet had the opposite effect. Once initial cellular changes had been induced the supplementary zinc seemed to accelerate their further advancement. Zinc-deficiency in animals fed a copper/zinc low-zinc diet was reflected in the plasma and liver zinc levels as well as in the copper/zinc ratio. The development of cancer was accompanied by a decrease in plasma zinc and an increase in the plasma copper/zinc ratio as well as in the liver zinc. These changes were most remarkable in the zinc-supplemented group.

4-Nitroquinoline-1-oxide↗

PubMed1978

Assessment of sub-clinical zinc-deficiency for carcinogenetic and other long-term studies in rats.

Explore the source record for details and available documents.

4-Nitroquinoline-1-oxide↗

PubMed1978

A microangiographic study of vascular changes in replanted and autotransplanted teeth of young dogs.

The purpose of the present investigation was to study the revascularization process of the pulp of replanted and autotransplanted teeth with incomplete root development in dogs. A barium-sulfate injection method combined with contact microradiography was used. Ingrowth of apparently new vessels was seen during the first postoperative days. After 10 days, visible vessels were seen in the apical half of the pulp, and after 30 days, in the whole pulp. Branches and apparently also anastomoses between pulpal vessels were seen after 10 days but were especially numerous after 30 days. One hundred eighty days postoperatively, only one of fifteen teeth was devoid of visible vessels, indicating pulpal necrosis. Thirteen of the remaining fourteen teeth exhibited visible vessels throughout the entire length of the pulp. It seems, therefore, that replanted and autotransplanted teeth with open apices have a high potential for repair. The revascularization of the pulp appeared to occur mainly by ingrowth of new vessels. In some instances, however, anastomoses seemed to form to pre-existing vessels in the pulp.

Animals↗

PubMed1978

Effect of age and diet on delta-aminolevulinic acid dehydratase in red blood cells.

ALA-D activity measured in the red blood cells of different species show considerable variations. Among the adult animals, rabbits have the highest activity and dogs, the lowest. It is a zinc-dependent enzyme and its activity is related to the age of the animals as well as the availability of zinc in the diet during the early growth period. Rats at partus have the highest ALA-D activity ever registered in any animal species and it decreases drastically during the early growth period. The red blood cells of newborn human babies have 50% higher ALA-D activity than that of adult man. When rats during their early growth period are fed on a diet containing 0.08 mmol zinc, there was a reduction in the enzyme activity whereas adult rats fed on diets containing higher and lower amounts of zinc did not show any change.

Adult↗

PubMed1977

Relation between zinc content in saliva and blood in healthy human adults.

Measurements were made of zinc levels in saliva, whole blood and plasma as well as copper levels in plasma by atomic absorption spectrophotometry. The mean zinc concentration (in ppm) was 0.478 (n = 136) in resting mixed saliva, 0.046 (n = 36) in parotid saliva, 6.41 (n = 145) in whole blood and 0.87 (n = 145) in plasma. The whole blood zinc levels were significantly lower in females than in males (P less than 0.001). Females and blood donors (males) had a significantly (P less than 0.001) higher Cu:Zn ratio than males (non-donors). It would thus appear, first, that the local effect of salivary zinc cannot be assessed simply from the concentration of zinc in stimulated parotid saliva since about nine-tenths of the zinc in resting mixed saliva is derived from other sources and, second, that the Cu:Zn in plasma is the most eligible variable for detecting sub-clinical Zn deficiency.

Adult↗

PubMed1976

Experimental oral cancer in rats with xerostomia.

Though previous experiments with fat-soluble carcinogens have demonstrated a protective effect of the saliva against chemically induced oral cancer it is not known if this also holds true for water-soluble carcinogenic agents. In vitro experiments indicate that the water-soluble 4NQO (4-nitrochinoline N-oxide) easily penetrates a layer of saliva similar with that normally present on the oral mucous membranes. It is possible that this quality, on intraoral applications of 4NQO, could eliminate the protective barrier of saliva. The protective effect of the saliva was examined in the present investigation. Xerostomia was induced in 15 rats and 4NQO was applied to the palate 3 times a week. After 4.7 months, on an average, palatal cancer appeared in all rats. In comparable investigations the result was 7 months with rats treated in an identical manner except for their salivary secretion remaining intact. This time difference represents approximately 33% of the time necessary for the development of oral cancer in normal rats by means of 4NQO. It was concluded, that a protective effect of the saliva exists whether the oral mucous membranes are attacked by water--or fat-soluble carcinogens.

4-Nitroquinoline-1-oxide↗

PubMed1976

Effects of essential fatty acid deficiency and of carbon tetrachloride-induced liver cirrhosis on oral carcinogenesis in the rat.

The relative resistance of the oral mucosa to carcinogenic influences was studied in connection with altered fatty acid composition of the oral epithelium in the rat. The water-soluble carcinogen 4-nitrochinoline N-oxide was used. The lipid changes were induced either through essential fatty acid (EFA) deficiency or through carbon tetrachloride-induced liver cirrhosis. Although the strongest initial reaction in the oral mucosa was seen in the EFA-deficient rats, a result considered to be due to increased permeability of the epithelium to the carcinogen, oral carcinoma did not develop earlier in the EFA-deficient group than in normal controls. The liver cirrhotic group developed clinical signs of carcinoma earliest (5.4 months) whereas in EFA-deficient and normal rats carcinoma appeared after an average of 6.0 and 6.5 months, respectively. However, as a previous study (Lekholm 1976) has shown that the fatty acid changes were less pronounced in cirrhotic than in EFA-deficient rats, it would appear that there is no clear correlation between the extent of lipid distrubance and reduced resistance of the oral epithelium to the induction of carcinoma.

4-Nitroquinoline-1-oxide↗

PubMed1975

Alterations in the lipid content of rat palatal epithelium during carcinogenesis.

The hard palates of 150 female albino rats of the Sprague-Dawley strain were painted 3 times a week either with the fat-soluble carcinogen 7,12-dimethylbenz(a)anthracene (DMBA) for 11 months with inhibited secretion of saliva or with the water-soluble carcinogen 4-nitrochinoline N-oxide (4NQO) for 8 months with intact salivary secretion. Specimens were taken regularly from the mucosa of the hard palate, and the content of lipids in the epithelium was studied histochemically and biochemically during the carcinogenesis. Changes in the lipid content could be observed histochemically as there was a focal loss of lipid stainability in the epithelium during the more advanced stages of carcinogenesis with severe epithelial dysplasia, carcinoma in situ and early invasive carcinoma. The biochemical method used (TLC) could not, however, verify the histologically observed changes in the lipid content of the epithelium, probably because the changes were very local.

4-Nitroquinoline-1-oxide↗

PubMed1975

Cytogenetic and histochemical analysis of experimental oral carcinogenesis in the rat.

The present investigation has shown that in chemical carcinogenesis progression of malignant epithelial changes in associated with an increased number of cells with chromosomal deviations. Each out of two oncogenic agents with different chemical characteristics had its own non-random pattern. There was usually a close relationship between such chromosomal changes and the simultaneous presence of morphological atypia (dysplasia) and metabolic atypia (aberrant G-6-P.DH activity) from moderate dysplasia and onwards during carcinogenesis. Changes in X-chromosomes, which i.a. in human code the synthesis of G-6-P.DH molecules, could perhaps explain and be reflected in deviating metabolic reactions in premalignant cells.

Animals↗

PubMed1974