Dynamic changes of serum gamma-glutamyl transferase in chronic alcoholism.

Elevated serum gamma-glutamyl transferase (GGT) levels were found in 29% of 155 chronic alcoholics undergoing detoxification treatment. Alkaline phosphatase (AP) was increased in 16%, alanine aminotransferase--SGPT (ALT) in 12% of the patients, while 23% had elevations of either AP or ALT or both. Of the foregoing parameters, GGT was the best single indicator of liver involvement. In course of the follow-ups GGT/ALT correlation improved, but GGT/AP correlation deteriorated. In 9 patients, abstinence during follow-up was associated with progressive decrease in previously elevated serum GGT. Because of its unique sensitivity, GGT may be useful as a screening and/or monitoring aid in alcoholism.     

Light and electron microscopic studies on capillaries of the goat cardiac muscle with special reference to the topographical relationship between the vessels and Purkinje fibers

The capillaries of the cardiac muscle were investigated in the goat by means of light microscopy, transmission electron microscopy and scanning electron microscopy, and the following results were obtained. The capillaries of the working cardiac muscles were numerous, arranged mainly parallel to the long axis of muscle cells and formed dense elongated networks. On the contrary, those of the terminal Purkinje fibers were relatively few in number, oriented in various directions and formed loose and circularly meshed networks surrounding the fibers. Such findings were discussed in correlation with the physiology and functional morphology of various types of the cardiac muscle cells.     

The effect of sedimentation and microbial nitrogen regeneration in a plankton community: a simulation investigation

A computer simulation model was developed to investigate nitrogenfluxes associated with microbial interactions in plankton communities.A short time scale was used, appropriate to the build-up anddecline of phytoplankton blooms in temperate shelf waters aftera mixing or upwelling event. The model depicts a continuum ofevents, many of which have been observed in coastal, upwellingand oceanic systems, including two phytoplankton peaks correspondingto ‘new production’ and ‘regenerated production’.It predicts that nitrogen loss through sedimentation of phytoplanktonand faeces may result in a smaller bloom with a delayed onsetand prolonged duration. Microbial regeneration of nitrogen wasfound to be important in sustaining the middle stages of a phytoplanktonbloom, whereas micro- and meso-zooplankton regeneration occurredtowards the end of the bloom.     

Correlation between the bone mass of athletes and biochemical and genetic markers of bone tissue remodeling

The association of the polymorphism of the VDR, Col1a1, and CALCR genes with a form of osteoporosis frequently occurring as a consequence of intense physical exercise in athletes was studied. Biochemical parameters of bone remodeling and its neuroendocrine regulation, as well as the bone masses, of 22 amateur athletes were determined immediately before a strenuous nine-week training cycle (TC) and eight months later. The possible association of these factors with the polymorphism of the genes coding for bone tissue proteins was studied. Long-term intense physical training was found to be associated with a significant activation of bone tissue resorption accompanied by continued rapid synthesis. Nevertheless, and in spite of the strong activation of resorption caused by the TC, the athletes exhibited no osteoporosis (even eight months after the discontinuation of the TC); some of them, however, displayed an individual tendency to osteopenia. According to the results of genetic analysis, this was associated with the polymorphism of predisposition genes (genotype TT of the VDR gene and the functionally weakened s allele of the Col1a1 gene).     

Radioimmunoassay for beta-endorphin (1-18), a novel pituitary peptide derived from proopiomelanocortin

A specific radioimmunoassay was developed for beta-endorphin (1-18). The content of beta-endorphin (1-18) immunoreactivity in rat tissues was as follows: posterior pituitary 260 ng/fragment, anterior pituitary 1.46 ng/mg, hypothalamus 11.9 pg/mg. The levels were undetectable (less than 3 pg/mg) in extrahypothalamic brain, pancreas, small intestine, prostata and testis. Gel filtration and reverse-phase HPLC studies indicated that most of rat anterior pituitary immunoreactivity is due to native beta-endorphin (1-18), whereas the bulk of posterior pituitary immunoreactivity corresponds to more hydrophobic material, probably N-acetyl-beta-endorphin (1-18). Thus, beta-endorphin (1-18) is a quantitatively important novel pituitary peptide derived from proopiomelanocortin. The posterior pituitary is an especially rich source of (N-acetyl)-beta-endorphin (1-18).