Granules of langerhans cells in the thymus contain gold

Summary The granules of Langerhans cells in the thymus of the rat were subjected to X-ray microanalysis. It was established that gold is present in these morphological structures.     

Purine nucleotide cycle as a possible anaplerotic process in rat skeletal muscle

Summary The intermediates of the purine nucleotide cycle (PNC) stimulated pyruvate oxidation by isolated skeletal muscle mitochondria in a system containing mitochondria and cytosol from rat skeletal muscle. Thus, in skeletal muscle the PNC might be involved in the anaplerotic supply of tricarboxylic acid cycle intermediates.Acknowledgment. This work was supported by a grant from the Polish Academy of Science within the project MR II.1.2.4.     

Different methotrexate effects in cultured normal and leukaemic human leukocytes

Summary Evidence is presented that the use of 2 different culture media, with or without methionine, can help to distinguish between normal and leukaemic methotrexate (MTX)-sensitive cells derived from chronic myeloid leukaemia patients. During the blast crisis MTX assays may help directly in the diagnostics of lymphoid involvement.This work was supported by the Polish Academy of Sciences within the project 09.7.4.1.4.Acknowledgments. We are indebted to Prof. Zofia Zieliska, Dept. of Cell Biochemistry, M. Nencki Institute of Experimental Biology PAN for providing the 5-methyltetrahydrofolate and for advice in these studies.     

Cluster analysis of dyad distributions in networks

Existing statistical models for network data that are easy to estimate and fit are based on the assumption of dyad independence or conditional dyad independence if the individuals are categorized into subgroups. We discuss how such models might be overparameterized and argue that there is a need for subgrouping methods to find appropriate models. We propose clustering of dyad distributions as such a method and illustrate it by analyzing how cooperative learning methods affect friendship data for school children.Work for this report was initiated while Frank and Komaska visited the Department of Statistics at the University of California, Riverside. Partial support was provided by the Swedish Council for Research in the Humanities and Social Sciences.     

TRH analogue with C-terminal thioamide group. Synthesis,receptor binding,TSH-releasing activity and α-MSH-releasing activity

Summary A new TRH analogue containing a C-terminal thioamide group was synthesized. This peptide was shown to have receptor-binding affinity, and TSH- as well as -MSH-releasing activities very similar to native TRH.Acknowledgments. This work was supported by the Swedish Natural Science Research Council (K-KU 3020-112) and the Polish Academy of Sciences (Research Grant No. MR I 12.1.6.1).     

Inhibition of new blood vessel formation in mice by systemic administration of human rib cartilage extract

Summary 1 M HCl-guanidine extract of human funnel chest rib cartilage administered i.v. to mice decreased specifically vasoproliferation induced by intradermal injection of allogeneic murine lymphocytes.Acknowledgments. This work was supported by grant No. 10.5. from the Polish Academy of Sciences. We wish to acknowledge the valuable help of Dr A. Piasek in cartilage extract preparation.     

Role of catecholamines in thyroxine-induced changes in metabolism and body temperature during exercise in dogs

Summary Blockade of beta receptors inhibited thyroxine-induced increases in T_re, blood FFA and LA levels during exercise in dogs.