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PubMed1976

Distribution of adenosine triphosphatase and thamine pyrophosphatase in the digestive system of Heteropneustes fossils.

Histochemical localization of adenosine triphosphatase and thiamine pyrophosphatase in the digestive system of the teleost fish, Heteropneustes fossilis has been studied. In the stomach, ATPase activity is observed in the mucosa, gastric glands and muscularis. The activity is stronger in the muscularis. Very weak TPPase activity is localized only in the mucosa and gastric glands. In the intestinal mucosa ATPase activity is stronger especially, along the brush border. Mild activity is also found in the connective tissue network and their nuclei, muscularis and serosa. In the posterior portion of the intestine and rectum, the localization pattern is similar to that of intestine but the activity is weaker. TPPase activity in the intestine and rectum is restricted only to the goblet shaped mucus secreting cells. In the liver, strong activity of ATPase and moderate activity of TPPase are found in the cytoplasm as well as the nuclei of the hepatic cells.

Adenosine Triphosphatases↗
PubMed1979

Bioassay of complex mixtures derived from fossil fuels.

The conversion or processing of shale, coal, or petroleum involves elevated temperatures and altered pressures, and under these conditions polynuclear aromatic hydrocarbons are likely to form. Certain compounds of this type exhibit carcinogenic activity for a variety of organ sites in experimental animals and epidemiological evidence strongly implicates their role as carcinogens in man. It is then not unexpected that many liquid fractions derived from shale and coal are carcinogenic when subjected to bioassay. Benzo(a)pyrene, [B(a)P], is frequently considered to be an indicator substance. It is clear that when a small quantity of B(a)P is present in a fraction, the fraction will exhibit carcinogenic activity in a bioassay (mouse skin). However, it does not follow that the lack of detectable B(a)P insures that the fraction will be noncarcinogenic. Several fractions have been analyzed for their content of B(a)P and then subjected to bioassay. A method for testing complex mixtures for their carcinogenic potential is described. The carcinogenic potency of these fractions are compared to petroleum fractions.

Animals↗
PubMed1976

Effect of heparin and adrenocorticotropin on the hepatic and serum cholesterol in catfish, Heteropneustes fossils.

The administration of heparin with or without ACTH significantly decreased hepatic cholesterol content in catfish. In serum, heparin alone produced first hypercholesterolemia which was followed by hypocholesterolemia whereas it potentiated hypercholesterolemic action of ACTH three hours after administration. It is concluded that heparin normally caused hypercholesterolemia by releasing cholesterol from liver as lipoprotein complex. The hypocholesterolemic action of heparin might be an indirect one.

Adrenocorticotropic Hormone↗
PubMed1976

On the cytoarchitecture of the corpuscles of Stannius of the catfish, Heteropneustes fossils (Bloch).

The cytoarchitecture of the corpuscles of Stannius (CS) of the catfish, Heteropneustes fossilis has been investigated. Based on the arrangement of septa and cells, at least 4 principal architectural patterns can be distinguished. In the first type, the cells appear either as cords or as follicles due to complete formation of thin septa. In the second category also, the penetrating septa are thin but divide the CS into incompletely delimited lobes. In the third type, the septa are thick and their branches unite, sometimes resulting in the formation of complete lobes. In the fourth type, each CS is formed of aggregates of lobes, each of which consists of a number of complete or incomplete lobules. The limitations involved in the classification of the CS into 4 types, on the basis of the septal arrangement, have been discussed in the light of the fact that H. fossilis possesses all the 4 types of CS.

Animals↗
PubMed1976

Characterization of 80-million-year-old mollusk shell proteins.

Fossil glycoproteins of the soluble organic matrix are present in an 80-million-year-old mollusk shell from the Late Cretaceous Period. Discrete molecular weight components, as determined by gel electrophoresis, are preserved. The fossil organic matrix was compared with the organic matrix of a living representative species of the same superfamily. A particular repeating amino acid sequence, found in contemporary mollusk shell proteins, was identified in the fossil glycoproteins. The ultrastructure, mineralogy, and chemistry of the inorganic components of the fossil and contemporary shells provide information on the state of preservation of the fossil. The use of fossil shell proteins to further our understanding of molecular evolution is discussed.

Amino Acids↗