Thiocyanate ion formation in rapeseed meals.

Meal prepared from unheated rapeseed (Brassica napus cv. Zephyr) showed the presence of t,iocyanate ion, while meal from heated seed of the same cultivar did not show detectable amounts. Unheated seed meal on autolysis, and heated seed meal on incubation with thioglucosidase, yielded increased amounts of thiocyanate ion. Various commercial rapeseed meals showed the presence of t,iocyanate ion only after enzyme incubation. Low glucosinolate, cv. Bronowski, and higher glucosinolate, cv. Zephyr on enzymic incubation yielded comparable amounts of thiocyanate ion, suggesting that the precursor responsible in the two varieties was the same and present in similar quantities. No formation of thiocyanate ion was observed on incubation of sinigrin with thioglucosidase. Rats dosed with heated meal, containing intact glucosinolate, showed a slight increase of thiocyanate ion in the urine as compared with control rats dosed with water, while a relatively large increase followed dosing with sinigrin. Rats dosed with meal containing free thiocyanate ion excreted the ingested thiocyanate ion almost quantitatively.     

Degradation of extracellular matrix proteins by hemorrhagic metalloproteinases

The proteolytic activity of four hemorrhagic metalloproteinases (Ht-a, c, d, and e) isolated from the venom of the Western diamondback rattlesnake (Crotalus atrox) was investigated using isolated extracellular matrix (ECM) proteins. We determined that all of the proteinases are capable of cleaving fibronectin, laminin, type IV collagen, nidogen (entactin), and gelatins. However, none of the proteinases were proteolytic against the interstitial collagen types I and III or type V collagen. With all of the substrates listed above Ht-c and Ht-d produced identical digestion patterns, as would be expected for these isoenzymes. With fibronectin, Ht-a produces a different ratio of products from Ht-c and Ht-d, while Ht-e produces a unique pattern of digestion. Ht-e and Ht-a produced nonidentical patterns with the laminin/nidogen preparation although some similarity was shared between them as well as with the Ht-c/d digestion pattern. Similar results were also observed for these proteinases with nidogen 150 as the substrate. The type IV collagen digestion patterns by Ht-e and Ht-a were similar to the pattern observed with Ht-c/d but differed by two bands. The digestion patterns of the three gelatins produced by the proteinases show differences between Ht-c and Ht-d when compared to Ht-e and Ht-a. This investigation clearly shows that several of the ECM proteins are efficiently digested by these toxins. The proteinases have some digestion sites in common but show differing specificities. In addition, the range of ECM proteins digested by these hemorrhagic proteinases is nearly identical to that demonstrated by the ECM proteinase stromelysin (MMP-3). From these data, and the knowledge of the roles these ECM proteins have in maintaining basement membrane structural/functional integrity, one can envision that the degradation of these ECM proteins could readily lead to loss of capillary integrity resulting in hemorrhage occurring at those sites.     

Photoelectric signals from dried oriented purple membranes of Halobacterium halobium

In dried oriented samples of purple membrane isolated from Halobacterium halobium, the photoelectric activity decreases and the light adaptation vanishes when the water content of the sample is lowered. In the photocycle the first steps of the proton movement were accelerated with decreasing humidity, while the last steps of the photocycle could not be observed. From the analysis of the photoelectric signal we conclude that at low humidities the protons move forward in the L decay and return to their original place during M decay.     

Seraspenide (acetylSDKP): phase I-II trial study of inhibitor of hematopoiesis protects against toxicity of aracytine and ifosfamide monochemotherapies]

Seraspenide, a synthetic tetrapeptide, inhibits cell cycle entry of normal hematopoietic stem cells. In mice it protects hemopoiesis against the damage caused by cytarabine, cyclophosphamide and carboplatin. Seraspenide has been given to 53 cancer patients undergoing monochemotherapy with cytarabine and ifosfamide in a double-blind cross-over randomized study. A significant protection of peripheral blood cells has been observed. Seraspenide has been devoided of toxicity.     

Efferent projections of mesencephalic locomotor neurons in the cat

Efferent neuronal projections of the mesencephalic locomotor region were investigated in cats using a horseradish peroxidase retrograde axonal transport technique. It was found that neurons located within the locomotor area form ascending and descending projections to many structures of the spinal cord and the brain but that short-axon connections running to the reticular formation of the midbrain and the medulla predominate. Small numbers of long-axon fibers may merge into the locomotor strips of the medulla and the spinal cord. The locomotor regions of the two halves of the midbrain are interlinked.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 18, No. 1, pp. 117–125, January–February, 1986.     

Effect of alkylresorcin on biological membranes during activation of lipid peroxidation

The effect of alkyl resorcin isolated from the cells of Azotobacter chroococcum and of its structural analog devoid of the alkyl chain (resorcin) on liver microsomes and brain synaptosomes of the rat as well as on rabbit skeletal muscle sarcoplasmic reticulum fragments during activation of lipid peroxidation was studied. Alkyl resorcin was shown to produce a much more potent antioxidant effect as compared with resorcin, since it inhibited lipid peroxidation in all the three types of membranes under study at much lower concentrations. Both alkyl resorcin and resorcin which inhibit lipid peroxidation prevented lipid peroxidation-induced structural-functional damages of synaptosomal and sarcoplasmic reticulum fragment membranes. Unlike resorcin, alkyl resorcin exerted an additional effect on brain synaptosomal membranes which consisted in the stabilization of barrier functions of membranes during incomplete inhibition of lipid peroxidation. The cumulative data suggest that stabilization necessitates the presence of both resorcin radical and alkyl chain in the alkyl resorcin molecule.