Possible Pathogenesis of Motility Changes in Diffuse Esophageal Spasm Associated with Gastric Carcinoma

A theory is proposed according to which diffuse esophageal spasm associated with carcinoma may be secondary to neural damage due to invasion by carcinoma without obstruction of the esophageal lumen. A case history is presented to support this theory.     

Local cerebral glucose utilization in the Ammon's horn and dentate gyrus of the rat brain

Summary The local cerebral glucose utilization (LCGU) was measured in different regions and layers of the Ammon's horn and dentate gyrus in the conscious rat. The LCGU was determined by quantitative [14C]2-deoxyglucose autoradiography using a computerized image processing system.In the hippocampus, the various regions and layers exhibited different glucose consumptions, the lowest values being found in the alveus and the highest ones in the lacunosum-molecular layers of the dentate gyrus' external limb. Additionally, in many layers, the LCGU values of the left hemispheres were found to be higher compared with the right hemispheres. The analysis of LCGU changes in rostrocaudal direction revealed, that in sector 1 of Ammon's horn and in the dentate gyrus the glucose consumption decreased from rostral to caudal levels, whereas in sector 3 of Ammon's horn an increase was found.Dedicated to Professor Dr. T.H. Schiebler on the occasion of his 65th birthday     

Plasmic degradation of human fibrinogen. IV. Identification of subunit chain remnants in fragment Y.

A method is presented for detection of cross-linking acceptor sites on fibrinogen chains, using monodansyl-cadaverine labeling in the presence of activated fibrin stabilizing factor, and polyacrylamide electrophoresis in the presence of sodium dodecyl sulfate. Fluorescent gamma-chain monomers and dimers were produced at a considerably faster rate than the labeled alpha-chain derivative. Purified fragments X, Y and D were prepared all from the same plasmic digest of fibrinogen. Following incubation with fibrin stabilizing factor, thrombin and monodansyl-cadaverine, they were reduced with beta-mercaptoethanol and examined by sodium dodecyl sulfate/acrylamide electrophoresis. Three gamma-chains (mol. wts 49 000, 42 000 and 39 000) had reacted with dansyl-cadaverine while no alpha-chain remnant took up the label. Additional protein and carbohydrate staining further facilitated identification of the individual subunit chains. At least three critical peptide bonds, located on alpha, beta- and gamma-chain remnants, must be broken during conversion of fragment Y into D and E. Sequential cleavage results in heterogeneous appearance of reduced subunit chains. As a consequence, there exist several molecular entities of fragment Y, all of which may have the same molecular weight though they represent various products of progressive plasmic digestion. Our results are compatible with the model of asymmetric degradation of fibrinogen, according to which fragment X produces 1 mol of fragment E e and 2 mol of the monomeric fragment D.     

Cellular osmoregulation in renal medulla

Cells of the renal medulla adapt osmotically to varying external electrolyte concentrations mainly by changing the intracellular content of small organic osmoeffectors (osmolytes) such as sorbitol, inositol and trimethylamines. This implies that despite extreme variations in extracellular tonicity the intracellular concentrations of monovalent electrolytes are stabilized at levels optimal for enzyme function and cell metabolism. In contrast to inorganic electrolytes these organic osmolytes are metabolically neutral and thus do not affect cell metabolism. In addition, some of these organic osmoeffectors, the trimethylamine compounds, are known to counteract the deleterious effects of high urea concentrations (prevailing in antidiuresis) on structure and function of cell proteins.     

A new analytical method for determining duration of phases, rate of DNA synthesis and degree of synchronization from flow-cytometric data on synchronized cell populations.

L-cells synchronized by mitotic selection were investigated by flow-cytometry and the fractions of cells in the various cell cycle compartments were determined as a function of time. A new analytical evaluation procedure was developed, by which the mean transit-times of cells through various cell cycle phases can be calculated from these data. Three examples for application of the method are presented: (1) determination of the duration of G1, S, G2 + M and of the whole cell cycle; (2) calculation of the rate of DNA synthesis in several subcompartments of the S-phase; and (3) evaluation of the degree of synchronization at different stages of the cell cycle.