Collateral projections of neurons from the lower part of the spinal cord to anterior and posterior cerebellar termination areas. A retrograde fluorescent double labeling study in the cat

The collateral projections of spinocerebellar neurons located in the L 2 to Ca 1 spinal segments in the cat were investigated by retrograde fluorescent double labeling technique. Rhodamine labeled latex microspheres (Rm) and Fast Blue (FB) were used for injections into the cerebellum in 8 cats. Two additional cats, with injections of Fluoro-Gold (FG) combined with Rm were excluded because lipofuchsin autofluorescence obscured the labeling. After injections with one tracer unilaterally in the paramedian lobule and another tracer bilaterally in the anterior lobe, double labeled neurons were found on the side of the paramedian lobule injection in the column of Clarke at L 2-L 4, laminae IV-VI at L 2-L 5 and the dorsolateral nucleus at L 2-L 6. After bilateral injections of one tracer in lobule VIII B and another in the anterior lobe, double labeled neurons were found bilaterally in the column of Clarke at L 2-L 4, laminae IV-VI at L 2-L 5, the medial part of lamina VII at L 6-L 7 and in certain cell groups at sacro-coccygeal levels. Neurons in the lateral part of lamina VII at L 3-L 5 and the ventrolateral nucleus of L 4-L 5 were labeled exclusively from injections in the anterior lobe. The findings indicate that spinocerebellar neurons at lumbar and more caudal levels of the cat spinal cord have different projection patterns in the cerebellum. A certain number of neurons which project to the anterior lobe have divergent axon collaterals supplying also the posterior vermis and/or the paramedian lobule. Other neurons project to the anterior or to the posterior lobe only.

Effect of immunostimulants and antitumor agents on tumor necrosis factor (TNF) production

OK-432, a lyophilized preparation of Streptococcus pyogenes, showed a priming activity for TNF production in mice, associated with an increase of spleen weight. PSK, a protein-bound polysaccharide preparation from Coriolus versicolor, did not show such activity. Both OK-432 and PSK potentiated the TNF production in mice primed with Corynebacterium parvum (CP) and challenged with Escherichia coli endotoxin (LPS). Cytotoxic antitumor agents of 5-fluorouracil (5-FU), cyclophosphamide (CY) and bleomycin (BLM) suppressed TNF production in mice primed with CP and challenged with LPS. TNF production suppressed by 5-FU, CY and BLM was partially restored by the combined treatment with OK-432 or PSK. These results suggest that the administration of cytotoxic antitumor agents suppresses the intrinsic TNF production in cancer patients, and the combined use of immunostimulants such as OK-432 and PSK is advantageous in restoring TNF production suppressed by cytotoxic antitumor agents.

Studies on RNA ligase activity in the brain and liver cells of mouse

RNA ligase in eukaryotic mammalian cells was studied by using mouse brain and liver cell extracts as enzyme sources and Oligo A as substrates. RNA ligase activity was determined by measuring the formation of alkaline phosphate-resistant product from 5'-32P-terminated Oligoribonucleotides. Under appropriate conditions, the activity of this enzyme in brain and liver cells may vary between 16-49 mU/ml. The joining way between donor and acceptor is 5'-P----3'-OH. Further studies were carried out by using synthetic UpCpU and 32pNp as substrates and crude enzyme preparations from extracts of cell nuclei of brain and liver as enzyme sources. RNA ligase activity was examined by homochromatography and autoradiography. A clear joining product was demonstrated and then isolated from the reaction mixture by DEAE-Sephadex A25 column chromatography. The eluted fractions were identified by DEAE-cellulose thin layer chromatography. The joining product was hydrolyzed either with KOH or with alkaline phosphatase, the autoradiographic spot of the product disappeared. In this case the joining way between donor and acceptor is 3'-P----5'-OH instead of 5'P----3'-OH. All this indicated that in extracts of mouse brain and liver cells most probably exists some other kind of RNA ligase, which differs from the T4 RNA ligase in the joining way.

The cytoarchitectonic organization of the spinal cord in the rat. I. The lower thoracic and lumbosacral cord

A laminar cytoarchitectonic scheme of the lower thoracic and lumbosacral segments of the rat spinal cord is presented in which Rexed's principles for the cat are applied. The material consists of 80-micron-thick sections stained with toluidine blue or according to van Gieson and 2-micron-thick sections stained with p-phenylenediamine or toluidine blue. The cytoarchitectonic organization of the rat spinal cord was found to be basically similar to that of the cat, although certain differences exist--for example, in the extension of the laminae. In addition to the laminar scheme, the distribution of certain cell groups, Lissauer's tract, and the pyramidal tract were investigated.