Particulate guanylate cyclase of skeletal muscle: effects of Ca2+ and other divalent cations on enzyme activity.

The properties of particulate guanylate cyclase (GTP pyrophosphate-lyase (cyclizing), EC 4.6.1.

Evidence for a K+, Na+ permeable channel in sarcoplasmic reticulum.

Potassium and sodium cation permeabilities of skeletal sarcoplasmic reticulum vesicles were characterized by means of 3H-choline, 22Na+ and 86Rb+ isotope efflux and membrane potential measurements. Membrane potentials were generated by diluting K gluconate filled sarcoplasmic reticulum vesicles and liposomes into Tris or Na gluconate media, in the presence or absence of valinomycin, and were measured using the voltage-sensitive membrane probe 3,3'-dipentyl-2,2'-oxacarbocyanine. About 2/3 of the sarcoplasmic reticulum vesicles, designated Type I, were found to be permeable to Rb+, K+ and Na+.

A co-operative numerical analysis of Mycobacterium gastri, Mycobacterium kansasii and Mycobacterium marinum.

A co-operative taxonomic study has been performed on slowly growing photochromogenic mycobacteria (Runyon Group I) and closely related organisms. Phenetic data on 54 strains, studied in seven laboratories, were collected and analysed by numerical taxonomic methods. Immunological properties and phage susceptibility patterns were analysed independently to establish correlation with numerical classification.

Uterine choriocarcinoma fourteen years following bilateral tubal ligation.

A patient who developed choriocarcinoma of the uterus 14 years after bilateral tubal ligation and resection is presented. Non-patency of the fallopian tubes was demonstrated radiologically. The various mechanisms of occurrence of the clinical picture are discussed.

Adenylate cyclase and phosphodiesterase activity in the platelet release abnormality.

11 patients with histories of clinical bleeding were selected as examples of platelet release abnormality. Mean bleeding time was 18 +/- 2.6 min (normal +/- SEM; 6 +/- 0.

Sources of Mycobacterium avium complex infection resulting in human diseases.

Human disease caused by organisms in the Mycobacterium avium complex occur virtually worldwide. A 20-year ongoing study conducted in Western Germany has been analyzed to elucidate the ecologic and epidemiologic characteristics of these infections in man. Organisms included in this investigation have been cultured from man, from domestic and wild animals and fowl, and from a variety of environmental sources.

Permeability of sarcoplasmic reticulum membrane. The effect of changed ionic environments on Ca2+ release.

Permeability properties and the effects of a changed membrane potential on Ca2+ release of sarcoplasmic reticulum vesicles of rabbit skeletal muscle were investigated by Millipore filtration. The relative permeability of sarcoplasmic reticulum to solutes determined under conditions of isotope exchange at equilibrium and/or under conditions of net flow of solute and water into the vesicles was as follows: sucrose, Ca2+, Mn2+ less than gluconate-, choline+, Tris+ less than methanesulfonate- less than urea, glycerol, K+, Na+,Li+, Cl-. Transient membrane potentials were induced by rapidly changing the ionic environment of the vesicles.

Isolation and characterization of two types of sarcoplasmic reticulum vesicles.

A purified preparation of sarcoplasmic reticulum from rabbit skeletal muscle has been found to consist of a heterogeneous population of vesicles. Isopycnic centrifugation was used to obtain "light" and "heavy" vesicles from the upper and lower ends of a 25 to 45% (w/w) linear sucrose gradient. Each fraction accounted for about 10 to 15% of the total vesicles.

Relationship between Mycobacterium simiae and Mycobacterium habana.

Strains of the species Mycobacterium simiae give a positive niacin test. On the basis of their cultural and biochemical characteristics and by seroagglutination they can be classified into 2 subspecies. (1) The strains of serotype M.