The antioxidant properties of lycopene

The antioxidant properties of the carotenoid lycopene were compared in three different model oxidative systems. In egg yolk liposomes, in the presence of 2.5 mM FeSO4 and 200 mM ascorbate, lycopene, alpha-tocopherol, and beta-carotene inhibited the accumulation of lipid peroxidation products reacting with 2-thiobarbituric acid (TBARS) in a dose-dependent mode, with the concentration of half-inhibition being 80, 30 and 130 mM, respectively. In the liposomes subjected to illumination with a He-Ne laser (632.8 nm) at a dose of 10.5 J/cm2, in the presence of 32.5 micrograms/ml hematoporphyrin derivatives (Fotogem, NIOPIC, Russia) TBARS accumulated, and this effect was inhibited by lycopene, alpha-tocopherol, and dihydroquercetin with approximately equal efficiencies (the half-inhibition concentrations were 10(-5) mM). In both systems studied, sodium azide at a concentration of 10 mM inhibited the TBARS accumulation by no more than 20%. Apparently, the inhibitory action of not only alpha-tocopherol, but also beta-carotene and lycopene was the result of their antiradical action, rather than quenching of the singlet oxygen in an aqueous medium. The introduction of lycopene, as well as beta-carotene in liposomes subjected to Fe(2+)-induced lipid peroxidation decreased the chemiluminescence (CL) intensity at the stage of CL slow flash, with no essential influence on the lag period. These data suggest that the effect of lycopene on lipid peroxidation was the result of its interaction with free radicals rather than chelating ferrous ions. The antiradical activity of lycopene was also confirmed by the method of luminol photochemiluminescence (PCL). Lycopene increased the PCL lag period (L) and decreased the PCL amplitude (A), which implies its antiradical and SOD-like activity in this system.     

Effect of ribonucleic acid on the function and structure of the pancreas and kidneys of rats with different concentrations of protein in their diets

Amputation on rabbits was found to change the muscle blood flow (MBF) in the limb subjected to surgery as well as in the contralateral extremity, depending on the technique used for amputation and the level at which it was carried out. Amputation was immediately followed by a reduction in MBF in the stump. After amputation of the crus and knee disarticulation, the flow was normalized a few days later and exceeded the preoperative mean flow. After amputation of the femur such an increase in flow was not seen, but when osseous plugging of the medullary cavity was applied, the MBF in the stump was intensified even after amputation of the femur.     

Nature of the reflex excitation of the spinal motor neurons in children with isiopathic scoliosis

In 32 girls from 12-14 years with expressed idiopathic scoliosis (III-IV stage) the authors studied H-reflexes, evoked from the soleus muscles. In 16 patients they established an expressed asymmetry in the expressivity of H-reflexes from the right and left sides. This asymmetry was found in a localization of the primary arch of spinal distortion in the sacral part. In a localization of the primary arch in the thoracal part, the asymmetry in the reflectory excitation of sacral motoneurons is not expressed. It is being assumed that changes in the motoneuron apparatus of the spinal cord are the reason of the appearance of a scoliotic deformation of the spine.     

Effect of heterochronic parabiosis on liver microsomal enzyme oxidation

Third molars have been associated with a host of pathologies and there are risks involved with their surgical removal. They also have the highest incidence of congenital absence of all the permanent teeth. The aim of this study was to determine the prevalence and distribution of congenitally missing third molars in local Chinese patients. The orthopantomographic radiographs of 786 Singaporean Chinese patients aged 12 to 16 years were examined. It was found that 562 (71.5%) of the children had all 4 third molars. Varying degrees of third molar agenesis were noted in the other 224 (28.5%) children. Of these, 43 (5.5%) showed total absence of third molars. There was no significant difference in agenesis between the right and left sides and no sexual predilection was noted. However, more third molars were missing from the maxilla compared to the mandible, the ratio being 3:2.