Levels of alpha1-antitrypsin in the spring and autumn seasons.

In a group of 84 pairs of 11-year-old children of both sexes, the level of the alpha1-antitrypsin (alpha1-AT) were ascertained in the autumn and spring. Although the mean levels of alpha1-AT in the two seasons hardly differed, the highly significant seasonal changes in the distribution curves of alpha1-AT values were noted in boys, whereas the levels showed higher stability in girls.     

Inhibition of testosterone biosynthesis by medrogestone

Résumé In vitro, la medrogestone bloque la synthèse des hormones dans les gonades par inhibition de la 3-hydroxystéroide ^4,5-isomérase. In vivo, la medrogestone réduit le niveau de testostérone dans le testicules de rat.

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We wish to thank Mrs.S. gosselin, Miss N. Jagarinec andMrs. F. Fitzsimons for their technical assistance andDr. G. Schilling for analyses by gas-liquid chromatography.     

Inhibition of human pancreatic elastase II activity on human aortic elastin by human alpha 2-macroglobulin

Human alpha 2-macroglobulin-human pancreatic elastase II binding were investigated using a homologous substrate, human aortic elastin, in order to test the enzymatic activity. We demonstrated that two moles of alpha 2-M are required to inhibit one mole of HPEII when the enzyme is added to a mixture of elastin and alpha 2-M. In addition, when the elastase-alpha 2-M complex is prepared under some circumstances, it exhibits an elastinolytic activity.     

DNA polymerases in human platelets]

Human platelets have two DNA polymerases. In the mitochondrial-free cytoplasm we have found a DNA polymerase gamma and another DNA polymerase very closely related to the polymerase alpha from animal cells. In the mitochondria only the gamma activity is present.     

Inhibition of neutrophil-mediated cytotoxicity by alpha 2 macroglobulin

Highly purified human alpha 2 macroglobulin (1.2--10 mg/ml) was shown to inhibit phytohemagglutinin-induced or antibody-induced lysis of chicken erythrocytes by polymorphonuclear neutrophils. Inhibition was not associated with impaired contact between effector and target cells but rather with the antiprotease activity of alpha 2 macroglobulin.     

Identification of cAMP dependant protein kinases in human lymphocytes]

Chromatographic purification by "DEAE" cellulose resolves the cAMP binding proteins in human lymphocytes into three parts. In presence of Mg++ each one possesses cAMP dependent protein-kinase activity, one of them showing allosteric characteristics.     

Receptors for cytomegaloviruses on the surface of human lymphocytes]

The relationships between cytomegalovirus (CMV) and lymphocytes have already been noted because of: (a) the immunological abnormalities induced by this virus, and (b) activation of latent CMV in the course of lymphocyte reactions associated with anti-histocompatibility antigen immune response. The present work shows that the lymphocyte surface may have specific receptors for CMV. Cultured fibroblasts infected with DMV were incubated with lymphocytes isolated from the blood of human immune subjects. Rosettes defined by the adherence of three or more lymphocytes around a fibroblast were formed in infected preparation while no rosettes were seen with normal control fibroblasts. Approximately 1.2 per cent of lymphocytes were involved in the formation of these rosettes. Rosette formation is inhibited when infected fibroblasts have been incubated with anti-CMV antibodies prior to the addition of lymphocytes.     

Immunocytochemical anatomy of alpha granules in the human endocrine pancreas]

Using the sensitive protein A-gold technique for the demonstration of antigenic sites in thin section for electron microscopy it was found that in the alpha granules of human pancreas, glucagon immunoreactivity (specific, C-terminal) is restricted to the dense granule core while glicentin immunoreactivity predominates on the peripheral halo surrounding the dense core.     

Inhibition of 9-amino-2-methoxy-6-chloroacridine fluorescence by human serum albumin]

Study of the fluorescence quenching of 9-amino 2-methoxy 6-chloro acridine upon serum albumine additions reveals a single protein fixation site. Characteristic values of thermodynamic functions are obtained from experiments at different temperatures.     

Inhibition of antigenic competition by immunostimulants]

The diminution of immune response against SRBC induced in mice, by a prior injection of HRBC was counteracted by addition of certain immunostimulants to SRBC. The intensity of inhibition of antigenic competition was related to the quantity of immunostimulant added to SRBC. Some immunostimulants (B. abortus, lipopolysaccharide) were more active than others (C. parvum, Poly I : C). To inhibit antigenic competition immunostimulant had to be injected after or in mixture with SRBC never before.     

Inhibition of phorbol myristate acetate and phytohemagglutinin stimulation of human lymphocytes by 13-cis-retinoic acid and ethyl etrinoate

Summary The retinol analogues 13-cis-retinoic acid and ethyl etrinoate inhibit the mitogenic activity of phorbol myristate acetate and phytohemagglutinin on human lymphocytes. This inhibitory effect is greater against the stimulation with phorbol myristate acetate than with phytohemagglutinin.This work was supported by a grant from the National Cancer Institute of Canada. We would like to thank Hoffmann-La Roche, Canada, for providing the 13-cis-retinoic acid and the ethyl etrinoate.     

Inhibition of tumor-induced angiogenesis and of tumor growth by activated lymphocytes

Summary Inhibition in angiogenesis (neo-vascularization) and of growth of a tumor piece graft in the anterior chamber of the eye of mice have been observed in the presence of activated syngeneic lymphocytes.Acknowledgment. The authors are thankful to ICMR, New Delhi, for financial assistance and to Mr N.C. Ghosh for illustration.     

Inhibition of DNA synthesis by lidocaine and procaine

Zusammenfassung Nachweis, dass in Ehrlich-Ascites-Zellen die DNS-Synthese durch Lokalanaesthetika stärker gehemmt wird als die RNS- und die Proteinsynthese.