Postnatal changes of some enzymatic activities of energy supplying metabolism in the cortex, inner and outer medulla of the rat kidney

1. In rat kidney cortex, outer and inner medulla the development of activities of seven enzymes was investigated during postnatal ontogeny (10, 20, 30, 60 and 90 days of age). The enzymes were selected in such a manner, as to characterize most of the main metabolic pathways of energy supplying metabolism: hexokinase (glucose phosphorylation, HK), glycerol-3-phosphate dehydrogenase (glycerolphosphate metabolism or shunt, GPDH), triose phosphate dehydrogenase (glycolytic carbohydrate breakdown, TPDH), lactate dehydrogenase (lactate metabolism, LDH), citrate synthase (tricarboxylic acid cycle, aerobic metabolism, CS), malate NAD dehydrogenase (tricarboxylic acid cycle, intra-extra mitochondrial hydrogen transport, MDH) and 3-hydroxyacyl-CoA-dehydrogenase (fatty acid catabolism, HOADH). 2. The renal cortex already differs metabolically from the medullar structures on the 10th day of life. It displays a high activity of aerobic breakdown of both fatty acids and carbohydrates. Its metabolic capacity further increases up to the 30th day of life. 3. The outer medullar structure is not grossly different from the inner medulla on the 10th day of life. Further it differentiates into a highly aerobic tissue mainly able to utilize carbohydrates. It can, however, to some extent, also utilize fatty acids aerobically and produce lactate from carbohydrates anaerobically. 4. The inner medullar structure is best equipped to utilize carbohydrates by anaerobic glycolysis, forming lactate. This feature is already pronounced on the 10th day of life, its capacity increases to some extent during postnatal development, being highest between the 10th and the 60th day of life.     

Protein diffusion in crowded electrolyte solutions

We report on a combined cold neutron backscattering and spin-echo study of the short-range and long-range nanosecond diffusion of the model globular protein bovine serum albumin (BSA) in aqueous solution as a function of protein concentration and NaCl salt concentration. Complementary small angle X-ray scattering data are used to obtain information on the correlations of the proteins in solution. Particular emphasis is put on the effect of crowding, i.e. conditions under which the proteins cannot be considered as objects independent of each other. We thus address the question at which concentration this crowding starts to influence the static and in particular also the dynamical behaviour. We also briefly discuss qualitatively which charge effects, i.e. effects due to the interplay of charged molecules in an electrolyte solution, may be anticipated. Both the issue of crowding as well as that of charge effects are particularly relevant for proteins and their function under physiological conditions, where the protein volume fraction can be up to approximately 40% and salt ions are ubiquitous. The interpretation of the data is put in the context of existing studies on related systems and of existing theoretical models.     

A physical (electromagnetic) model of differentiation. 1. Basic considerations

There are a number of biological phenomena and events that cannot yet be adequately described, such as cell growth and differentiation, which may be controlled by physical factors. Fr?hlich (1980) has discussed the principles of dissipative structures as applied to electromagnetic interactions in relation to basic couplings in biological systems. Recently, increasing evidence of photon storage and ultraweak photon emission from living systems, particularly from DNA, has suggested the concept of an electromagnetic model of differentiation, based on the known quantum optical properties of nucleic acids. This model has the advantage over all ideas so far published, that it is (1) simple; (2) universally applicable to events in living matter, because it is consistent with both the quantum mechanical and the thermodynamic properties on the one hand, and the known biological and biochemical data and phenomena at the other hand; (3) it not only describes the phenomena and events in terms of pure mathematical parameters, but it can also explain them; and (4) it escapes the difficulty of finding basic control mechanisms, which themselves do not need a regulator, ad infinitum.     

Electrochemistry of cyclic alpha-imino carboxylates and their metal complexes: correlation with physiological activity

Cyclic voltammetry data were obtained for delta 1-pyrroline-2-carboxylate, delta 3-thiazoline-4-carboxylate, delta 2-thiazoline-2-carboxylate and their complexes with Cu(II), Fe(III), and Fe(II). The free ligands were reduced at about -0.35 V and were oxidized in the range of 0.42-0.52 V. Complexing the imine carboxylates with metal ions produces reduction and oxidation in the ranges of 0.05-0.37 V and 0.52-0.74 V, respectively. Prior reports show that these ligands take part in various biological functions. We propose that electron transfer may be involved in some aspects of the physiological activity. The captodative effect can be applied.     

Light-stimulated ultraweak photon reemission of human amnion cells and Wish cells

Photon reemission in the ultraweak intensity range that is observed after irradiation of cell suspensions with light, reveals characteristic differences between normal human amnion cells and transformed Wish cells from the same parental tissue. The reemission kinetics, approximated best by a hyperbolical process, were studied as a function of cell density, showing that: malignant Wish cells have a photon storage capacity that is not improved by increasing the cell density; and that normal amnion cells exhibit a photon storage capacity that strongly increases with increasing cell density. The interpretation of this effect and the nature of the emitter are discussed.     

A unique alpha chain in hemoglobin of “Skive” DanishMus musculus

The primary structures of the alpha chains in hemoglobins from three stocks of mice with theHba ^w2,Hba ^w3, andHba ^w4 haplotypes were determined to establish whether the tentative alpha-chain assignments based on the results of isoelectric focusing patterns were correct. TheseHba haplotypes were identified in laboratory descendants of feral mice captured in different parts of the world. Hemoglobin from Centreville, Maryland,Mus musculus domesticus (Hba ^w2) contains equal amounts of alpha chains 1 and 3. Hemoglobin from CzechMus musculus musculus (Hba ^w4) contains equal amounts of alpha chains 3 and 4. Amino acid analysis of the alpha-globins of Skive DanishMus musculus musculus (Hba ^w3) establishes that its hemoglobin is comprised of about one-third alpha chain 2 as expected plus a greater amount of a unique alpha chain that has not been described previously. This unique alpha chain has glycine at position 25, isoleucine at position 62, and serine at position 68; it is called chain 7. It may represent an intermediate in the evolution of genes that code for chain 2 (which has glycine, valine, and serine at positions 25, 62, and 68, respectively) and chain 4 (which has valine, isoleucine, and serine at positions 25, 62, and 62, respectively).This research was sponsored jointly by the National Institutes of Environmental Health Sciences under Contract 1-ES-55078 and by the Office of Health and Environmental Research, U.S. Department of Energy, under Contract DE-AC05-840R21400 with Martin Marietta Energy Systems, Inc.     

Studies on lung surfactant replacement in respiratory distress syndrome. Rapid film formation from binary mixed liposomes

Binary mixed liposomes were prepared from dipalmitoylphosphatidylcholine (DPPC) and a minor compound, e.g., egg phosphatidylglycerol (PG) at a ratio of 9:1. Using different preparative techniques, large unilamellar vesicles (LUV), small unilamellar vesicles (SUV) or multilamellar vesicles (MLV) were obtained and were studied with an electron microscope for morphology, with a Wilhelmy balance for spreading and surface tension lowering potential, and in the surfactant-depleted isolated rat lung for their ability to restore expiratory lung capacity. Only the simultaneous investigation of phospholipids by negative staining and thin sectioning allows unequivocal classification of liposomes. The surface-active structures prepared with the technique of Bangham et al. (Bangham, A.D., Hill, M.W. and Miller, N.G.A. (1974) in Methods in Membrane Biology (Korn, E., ed.), Vol. 1, pp. 1-68, Plenum Press, New York) at room temperature are LUV. LUV containing DPPC:PG at a ratio of 9:1 rapidly spread to a film with high surface tension lowering potential. Within 5 min after injection into the subphase they rise to the surface and form a film at the air/liquid interface able to lower the surface tension to less than 1 mN/m at compression. SUV of the same chemical composition, however, are immediately surface-active only when spread directly onto the surface. MLV exhibit poor surface activity. LUV or pure DPPC, applied onto the surface, are weakly surface active within 5 min. DPPC vesicles injected into the subphase at 37 degrees C do not adsorb to any film with surface tension lowering potential in this time. The minor compounds PE, PI, PS, PA, lysoPC enable DPPC to form surface-active films after application on saline at 37 degrees C. Removal of surfactant decreases the expiratory lung capacity of the isolated rat lung from 49.7 to 12.4% at 4 cmH2O. After substitution with natural surfactant, the expiratory lung capacity is twice that of the washed lung (25.9%), but the original distensibility of the native lung is not restituted. The effect of LUV containing DPPC:PG at a ratio of 9:1 is also remarkable (21.2%).     

Inhibition of protein synthesis and induction of helical polysomes in rat liver by N-hydroxy-2-fluorenylacetamide

After a single intraperitoneal injection of the hepatocarcinogen N-hydroxy-2-fluorenylacetamide (OH-FAA), numerous helical polysomes were found in the hepatocytic cytoplasm at 2 and 6 but not 24 h after treatment. Electron microscopy also demonstrated nucleolar segregation, disarray of endoplasmic reticuium (ER), and disaggregation of polyribosomes at the times when helical polysomes were present. Polyribosome disaggregation was confirmed and quantified by determining size distribution of polyribosomes at 2 h after OH-FAA treatment. Protein synthesis was inhibited at the time of helical polysome induction but the degree of inhibition did not noticeably alter the number of helical polysomes found electron microscopically.     

Die submikroskopische Struktur der Assimilatleitbahnen von Polytrichum commune

Summary In the young part of the stem of Polytrichum commune the protoplasts of the two types of conducting cells, the leptoids and parenchyma cells, are nearly identically equipped with cell organelles and cytoplasmic structures. Both types contain a nucleus, chloroplasts, mitochondria, and dictyosomes. The endoplasmic reticulum builds characteristic cisterns in form of hollow cylinders extending from one end wall to the other. The cisterns are connected with many plasmodesmata, which occur only in the end walls. Leptoids have oblique end walls with 16 to 20 plasmodesmata per m², and parenchyma cells show cross walls perpendicular to the axis with 9 to 12 plasmodesmata per m².Since the leptoids are supposed to be the pathways for the longitudinal transport of assimilates (Eschrich and Steiner, 1967, 1968), it is of interest that early in their development these elements undergo a change in their protoplasmatic structure. Two to 3 cm below the apical cell the protoplasts degenerate and show lysosome-like structures. The endoplasmic reticulum and other structures are deformed or dissolved; the plasmodesmata are constricted by callose deposits. At the same level the parenchyma cells still retain the original structure of their protoplasts.Thus, assimilates moving upward in one row of leptoids may penetrate the whole lumen of the leptoids at lower levels, but they are restricted to the cisterns of the endoplasmic reticulum at higher levels of the stem.