Publications

Export 42 results:
Sort by: Author Title Type [ Year  (Desc)]
1975
Coscia, L., P. Causa, E. Giuliani, and A. Nunziata, "Pharmacological properties of new neuroleptic compounds.", Arzneimittel-Forschung, vol. 25, issue 9, pp. 1436-42, 1975 Sep. Abstract

RMI 61 140, RMI 61 144 and RMI 61 280 are newly synthetized N-[8-R-dibenzo(b,f)oxepin-10-yl]-N'-methyl-piperazine-maleates which show interesting psychopharmacologic effects. This work contains the results of a study performed with these three compounds, in order to demonstrate their neuropsycholeptic activity in comparison with chloropromazine (CPZ) and chlordiazepoxide (CPD). The inhibition of motility observed in mice shows that the compounds reduce the normal spontaneous motility as well as the muscle tone. The central-depressant activity is evidenced by increased barbiturate-induced sleep and a remarkable eyelid ptosis can also be observed. Our compounds do not show any activity on electroshock just as do CPZ and CPD. As to the antipsychotic outline, our compounds show strong reduction of lethality due to amphetamine in grouped mice and a strong antiapomorphine activity. They show also an antiaggressive effect and an inhibitory activity on avoidance behaviour much stronger than CPZ. We have also found extrapyramidal effects, as catalepsy, common to many tranquillizers of the kind of the standards used by us. As for vegetative phenomena, the compounds show hypotensive dose related action ranging from moderate to strong, probably due to an a-receptor inhibition. Adrenolytic activity against lethal doses of adrenaline, antiserotonin and antihistaminic effects, as well as other actions (hypothermia, analgesia, etc.) confirm that RMI 61 140, RMI 61 144 and RMI 61 280 are endowed with pharmacologic properties similar and more potent than those of CPZ. Studies on the metabolism of brain catecholamines show that they are similar to CPZ, although with less effect on dopamine level.

Hendrickson, W. A., and K. B. Ward, "Atomic models for the polypeptide backbones of myohemerythrin and hemerythrin.", Biochemical and biophysical research communications, vol. 66, issue 4, pp. 1349-56, 1975 Oct 27. Abstract
n/a
Wiesmann, U. N., S. DiDonato, and N. N. Herschkowitz, "Effect of chloroquine on cultured fibroblasts: release of lysosomal hydrolases and inhibition of their uptake.", Biochemical and biophysical research communications, vol. 66, issue 4, pp. 1338-43, 1975 Oct 27. Abstract
n/a
Smith, R. J., and R. G. Bryant, "Metal substitutions incarbonic anhydrase: a halide ion probe study.", Biochemical and biophysical research communications, vol. 66, issue 4, pp. 1281-6, 1975 Oct 27. Abstract
n/a
Chow, Y. W., R. Pietranico, and A. Mukerji, "Studies of oxygen binding energy to hemoglobin molecule.", Biochemical and biophysical research communications, vol. 66, issue 4, pp. 1424-31, 1975 Oct 27. Abstract
n/a
Crow, T. J., J. F. Deakin, and A. Longden, "Proceedings: Do anti-psychotic drugs act by dopamine receptor blockade in the nucleus accumbens.", British journal of pharmacology, vol. 55, issue 2, pp. 295P-296P, 1975 Oct. Abstract
n/a
Sinelnikova, E. M., T. V. Dvoretskova, and Z. S. Kagan, "[Intermediate plateaux in kinetics of the reaction catalyzed by biodegradative L-threonine dehydratase from Escherichia coli].", Biokhimii︠a︡ (Moscow, Russia), vol. 40, issue 3, pp. 645-51, 1975 May-Jun. Abstract

It has been shown that for the reaction catalyzed by "biodegradative" L-threonine dehydratase from E. coli strains K-12 and 980 in 0.5 M phosphate-carbonate buffer, pH 8.4 and pH 9.5, the plots of initial reaction rate (v) versus the initial substrate concentration ([S]0 are characterized by several inflection points, i. e. an intermediate plateau. The plot of v versus the allosteric activator (AMP) concentration have very complicated shapes: there are several inflection points, and also the maximum at L-threonine concentration equal to 3-10(2) and 5-10(-2) M. High AMP concentrations inhibit the enzyme at high substrate concentrations. The reduced glutathion dose not influence the enzyme and does not alter the activating effect of AMP. On the basis of the data obtained it is proposed that the substrate and AMP shift the equilibrium between multiple oligomeric enzyme forms differing in catalytic activity and kinetic manifestations of allosteric interactions between the active and allosteric AMP-binding sites towards polymerization. Thus, the functioning the enzyme under study is discussed in the frames of the model of dissociating regulatory enzymes with multiple intermediate oligomeric forms.

Makar, A. B., K. E. McMartin, M. Palese, and T. R. Tephly, "Formate assay in body fluids: application in methanol poisoning.", Biochemical medicine, vol. 13, issue 2, pp. 117-26, 1975 Jun. Abstract
n/a
Mier, P. D., and J. J. van den Hurk, "Lysosomal hydrolases of the epidermis. I. Glycosidases.", The British journal of dermatology, vol. 93, issue 1, pp. 1-10, 1975 Jul. Abstract

Seven distinct glycosidases (EC 3.2) have been characterized in guinea-pig epidermis. Their properties indicate them to be of lysosomal origin. The 'profile' of the epidermal glycosidases is significantly different from that reported for whole skin, the activities of beta-galactosidase and beta-acetylglucosaminidase being very high and those of the remaining enzymes relatively low in epidermis.

Fahnestock, S. R., "Evidence of the involvement of a 50S ribosomal protein in several active sites.", Biochemistry, vol. 14, issue 24, pp. 5321-7, 1975 Dec 2. Abstract

The functional role of the Bacillus stearothermophilus 50S ribosomal protein B-L3 (probably homologous to the Escherichia coli protein L2) was examined by chemical modification. The complex [B-L3-23S RNA] was photooxidized in the presence of rose bengal and the modified protein incorporated by reconstitution into 50S ribosomal subunits containing all other unmodified components. Particles containing photooxidized B-L3 are defective in several functional assays, including (1) poly(U)-directed poly(Phe) synthesis, (2) peptidyltransferase activity, (3) ability to associate with a [30S-poly(U)-Phe-tRNA] complex, and (4) binding of elongation factor G and GTP. The rates of loss of the partial functional activities during photooxidation of B-L3 indicate that at least two independent inactivating events are occurring, a faster one, involving oxidation of one or more histidine residues, affecting peptidyltransferase and subunit association activities and a slower one affecting EF-G binding. Therefore the protein B-L3 has one or more histidine residues which are essential for peptidyltransferase and subunit association, and another residue which is essential for EF-G-GTP binding. B-L3 may be the ribosomal peptidyltransferase protein, or a part of the active site, and may contribute functional groups to the other active sites as well.

Baccanari, D., A. Phillips, S. Smith, D. Sinski, and J. Burchall, "Purification and properties of Escherichia coli dihydrofolate reductase.", Biochemistry, vol. 14, issue 24, pp. 5267-73, 1975 Dec 2. Abstract

Dihydrofolate reductase has been purified 40-fold to apparent homogeneity from a trimethoprim-resistant strain of Escherichia coli (RT 500) using a procedure that includes methotrexate affinity column chromatography. Determinations of the molecular weight of the enzyme based on its amino acid composition, sedimentation velocity, and sodium dodecyl sulfate gel electrophoresis gave values of 17680, 17470 and 18300, respectively. An aggregated form of the enzyme with a low specific activity can be separated from the monomer by gel filtration; treatment of the aggregate with mercaptoethanol or dithiothreitol results in an increase in enzymic activity and a regeneration of the monomer. Also, multiple molecular forms of the monomer have been detected by polyacrylamide gel electrophoresis. The unresolved enzyme exhibits two pH optima (pH 4.5 and pH 7.0) with dihydrofolate as a substrate. Highest activities are observed in buffers containing large organic cations. In 100 mM imidazolium chloride (pH 7), the specific activity is 47 mumol of dihydrofolate reduced per min per mg at 30 degrees. Folic acid also serves as a substrate with a single pH optimum of pH 4.5. At this pH the Km for folate is 16 muM, and the Vmax is 1/1000 of the rate observed with dihydrofolate as the substrate. Monovalent cations (Na+, K+, Rb+, and Cs+) inhibit dihydrofolate reductase; at a given ionic strength the degree of inhibition is a function of the ionic radius of the cation. Divalent cations are more potent inhibitors; the I50 of BaCl2 is 250 muM, as compared to 125 mM for KCl. Anions neither inhibit nor activate the enzyme.

Goss, D. J., L. J. Parkhurst, and H. Görisch, "Kinetic light scattering studies on the dissociation of hemoglobin from Lumbricus terrestris.", Biochemistry, vol. 14, issue 25, pp. 5461-4, 1975 Dec 16. Abstract

The kinetics of the pH-induced dissociation of the 3 X 10(6) mol wt hemoglobin from Lumbricus terrestris (the earthworm) have been studied in a light-scattering stopped-flow apparatus. The ligand dependent dissociation data were fit well by a simple sequential model. The data for CO and oxyhemoglobin are consistent with Hb12 leads to 2Hb6 leads to 12Hb. Methemoglobin at pH 7 appears to be hexameric and the dissociation is consistent with the model: Hb6 leads to 6Hb. In a sequential decay scheme for which light-scattering changes are monitored, the relative amounts of rapid and slow phase are determined by the rate constants as well as the molecular weights of intermediate species. Assignment of the hexameric intermediate is supported by an investigation of the sensitivity of the theoretical kinetic curves to the molecular weights of the intermediates. This assignment is further supported by the following: (1) the same model will fit the data for oxy- and CO-hemoglobin at all three temperatures (a 24-29-fold variation in rate constants), (2) evidence from electron microscopy shows hexameric forms, and (3) methemoglobin is apparently stable as a hexamer at pH 7. When CO replaces O2 as the ligand, the dissociation rate increases by a factor of four. The met is about 20 times faster than the initial oxyhemoglobin dissociation rate, but perhaps more relevant for comparing dissociation of the hexamer, the met rate was respectively 100 times and 500 times faster than that for the assumed hexameric forms of CO- and oxy-hemoglobin. The activation energies for the dodecamer to hexamer dissociation and for the dissociation of the hexamer to smaller forms were about 30 kcal/mol for oxy-, CO-, and methemoglobin.

Jallon, J. M., Y. Risler, and M. Iwatsubo, "Beef liver L-Glutamate dehydrogenase mechanism: presteady state study of the catalytic reduction of 2.oxoglutarate by NADPH.", Biochemical and biophysical research communications, vol. 67, issue 4, pp. 1527-36, 1975 Dec 15. Abstract
n/a
Asakura, T., K. Adachi, M. Shapiro, S. Friedman, and E. Schwartz, "Mechanical precipitation of hemoglobin köln.", Biochimica et biophysica acta, vol. 412, issue 2, pp. 197-201, 1975 Dec 15. Abstract

Hb Köln (beta 98 Val leads to Met) was found to precipitate rapidly during mechanical shaking. The rate of precipitation of Hb Köln is 5-6 times faster than that of Hb S. The kinetics of precipitation of the patient's hemolysate, which is a mixture of Hb Köln and Hb A, showed a biphasic curve indicating that Hb Köln precipitates independently from Hb A. The instability of Hb Köln may be attributed to the conformational change in the vicinity of heme. The mechanical shaking may be used as a new method for detection and quantitation of hemoglobin Köln and other unstable hemoglobins.

Moroi, K., and T. Sato, "Comparison between procaine and isocarboxazid metabolism in vitro by a liver microsomal amidase-esterase.", Biochemical pharmacology, vol. 24, issue 16, pp. 1517-21, 1975 Aug 15. Abstract
n/a
Anderson, T. R., and T. A. Slotkin, "Maturation of the adrenal medulla--IV. Effects of morphine.", Biochemical pharmacology, vol. 24, issue 16, pp. 1469-74, 1975 Aug 15. Abstract
n/a
Jolly, R. D., K. G. Thompson, and B. G. Winchester, "Bovine mannosidosis--a model lysosomal storage disease.", Birth defects original article series, vol. 11, issue 6, pp. 273-8, 1975. Abstract
n/a
Tourism