A pyruvate kinase variant in different mouse transplanted tumors

Summary Mouse transplanted tumors, in contrast to normal tissues, contain a pyruvate kinase (PK) variant sensitive to the inhibitory action of L-cysteine and less sensitive to saturated fatty acids than the normal enzyme. In selected normal and tumor materials two fractions of PK were separated. Fraction A (20–30% (NH₄)₂SO₄ saturation) dominated in normal liver, and fraction B (50–60% (NH₄)₂SO₄ saturation) in skeletal muscles and Ehrlich ascites tumor. Only this fraction B from tumor material was sensitive to L-cysteine, and seems to contain a tumor-specific PK variant which might be considered as a marker of neoplastic transformation in a broad spectrum of mouse experimental tumors.     

Juvenilizing effect of ecdysone mimic RH 5849 inGalleria mellonella larvae

The response of the final instar larvae ofG. mellonella to topical application of the non-steroidal ecdysone mimic, RH 5849, was age-related as well as dose-dependent. In young final instar larvae, moderate doses of RH 5849 induced perfect supernumerary larval moults, but doses equal to and higher than 8.5 μg per larva caused premature formation of larval cuticle and were lethal. Application of RH 5849 significantly increased allatotropic activity of the brain, and also activated synthesis of juvenile hormone (JH) by the corpora cardiaca/corpora allata complex. Simultaneous application of RH 5849 and FMev, a potent inhibitor of JH synthesis, to young final instar larvae lowered the incidence of perfect supernumerary larval moults. We conclude that the effect of RH 5849 on the developmental programme inG. mellonella is mediated by the corpora allata.     

A note on the use of protease inhibitors during chromatin fractionation on hydroxyapatite columns

It was found that NaHSO3 present in the eluents enabled full and reproducible recovery of chromosomal proteins from a hydroxyapatite column. Another protease inhibitor, PMSF, did not have that effect.     

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

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 alpha-MSH-releasing activities very similar to native TRH.     

The effect of intraventricular thyroxine administration on body temperature in dogs at rest and during physical exercise

Summary Infusion of 1 g thyroxine into the left cerebral ventricle of the dog did not change body temperature at rest, but it caused significantly higher increases in T_re during physical exercise.     

Organoselenides as potential immunostimulants and inducers of interferon gamma and other cytokines in human peripheral blood leukocytes

Summary A number of organoselenium compounds have been described as anti-inflammatory, antioxidant, glutathione peroxidase-like agents and inhibitors of prostaglandin synthesis. Here we report that bis [2-(N-phenyl-carboxamido)]phenyl diselenide, 2-phenyl-1,2-benzisoselenazol-3(2H)-one (Ebselen) and related compounds are inducers of interferon gamma (IFN-) and tumor necrosis factor (TNF) in human peripheral blood leukocytes. The IFN and TNF response was rapid, occurring within 20 h, and high-up to 1000 and 2000 units ml^–1-and was clearly related to the dosage and the structure of the compounds. The action of the compounds and phytohemagglutinin was synergistic. The IFN gamma and TNF production was reduced after removing adherent cells. Although the mode of action of the compounds is not known, they appear to interact directly or indirectly with both adherent and non-adherent leukocytes, and stimulate the synthesis of a set of different cytokines including factors controlling the cell proliferation. Therefore, organoselenides may be regarded as the biological response modifiers.     

Glutaminase activity in rat skeletal muscle mitochondria

Isolated rat skeletal muscle mitochondria took up about 40-ng-atoms O per mg protein, with glutamine as the only respiratory substrate. The mitochondria incubated in the presence of glutamine and KCN formed both ammonia and glutamate in equivalent amounts. The experiments reported here provide suggestive evidence that rat skeletal muscle mitochondria contain glutaminase (L-glutamine amidohydrolase EC 3.5.1.2.) activity.     

Polish Mathematical School 1915—1939

本文展示和介绍了二十世纪上半叶（１９１５－１９３９）波兰数学领域的主要成就。在华沙、利活夫数学学校的创立，一些数学创始人在数学教育、教学上所做的努力，培养了一批世界级顶尖的数学大师；在学术研究上，创办了如《基础数学》杂志等数学刊物，国外学者到学校讲学，召开学术会议吸引了全世界各国的数学家进行了广泛的合作和交流，使波兰在集合理论、拓扑学、实值函数理论等方面取得了历史上开创性的进展，为世界数学的发展作     

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

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.