NADPH-dependent reduction of amaranch in liver microsomes characterized the quantity of low spin forms of cytochrome P-450.

We confirmed that NADPH-dependent anaerobic amaranch reduction in rat liver microsomes is compatible with the interaction of the dye with Fe(III) heme of cytochrome P-450 as the type II substrate. This process is rate-limiting in the whole reaction. High positive correlation (r = 0.949) between the values of Vmax for reaction of NADPH-dependent anaerobic amaranch reduction and the relative content low spin forms of cytochrome P-450 determined by ESR in microsomes from liver of control and induced by PB, BP, IS and 4-MP rats was observed. Relative content of low spin forms of cytochrome P-450 determined by ESR was increased according to BP less than PB less than control less than IS approximately 4-MP; Vmax values increased according to BP less than PB less than control less than IS less than 4-MP. Thus, reaction of NADPH-dependent anaerobic amaranch reduction may be used for determination of low spin forms of cytochrome P-450 at physiological conditions.     

Effect of Lincocin Treatment on the Greening Process in Bean (Phaseolus vulgaris) Leaves

The effect of lincocin (a plastid protein synthesis inhibitor) treatment on the greening process of bean (Phaseolus vulgaris L.) leaves have been studied. In comparison with control leaves treated ones had a decreased rate of chloroplast development. They had a marked chlorophyll deficiency and a decreased chlorophyll a/b ratio. Some long and short wavelength forms of chlorophyll a were lacking as evidenced from the absorption spectra at 25°C and the fluorescence spectra at 77°K. The –¹⁴CO₂ fixation was inhibited by 80–90% in treated leaves. The fluorescence induced by the measuring light was greater in the treated leaves than in the control ones, and the kinetics of the decline of the relative fluorescence intensity were also different. Electron microscopic studies showed macrogranum-like structures and incomplete membrane vesicles in the treated plastids. After longer treatment a destruction of membranes was observed. The results indicate some structural and functional membrane deficiencies and instability of the membranes.     

Comparative characterization of the ultrastructure of intestinal epithelium of various sturgeon species

The ultrastructure of the mid-intestine of four sturgeon species and their hybrids was studied. Apart from enterocytes and glandular goblet cells, the cells with microvilli, endocrine cells, and immunocompetent elements were revealed. Specific cells responsible for the primary immune response, analogous to mammalian M-cells, were discovered in sturgeon fishes. The ultrastructural characteristics common for the mid-intestinal epithelium of all the sturgeon fishes studied were determined. Species-specific features of intestinal epithelium of the parent species, which were characteristic of the hybrids, were revealed.     

Germline and Somatic Mutations in Archived Breast Cancer Specimens of Different Subtypes

Molecular Biology - Molecular profiling of tumors may provide promising options for personalized treatment. We have examined the spectrum of germline and somatic mutations in 23 breast cancers (BC)...     

Fine structure of the female reproductive system in Sobolevicanthus gracilis and Cloacotaenia megalops (Cestoda: Cyclophyllidea)

The fine structure of the female reproductive organs and ducts in two cyclophyllidean cestodes was studied by transmission electron microscopy. All the studied ducts (vitelline, fertilization and vaginal ducts, and oviducts) as well as the uterine and ootype walls have the luminal surface elevated to form apical cytoplasmic lamellae and are surrounded by bands of circular muscules, which are attached to the basement layer. The structure of the studied ducts epithelium corresponds to the pattern described in other ducts of the cestode genital system, namely a nucleate syncytial layer. An exception is the vagina Sobolevicanthus gracilis, in which the surface is lined with not numerous atypical microtriches. The comparison of our results and the data reported for other species is given. It is found out that in different species of cestodes forming oligolecital eggs, there are observed various uterine structures and diverse contacts between the eggs capsules and the uterine epithelium. The formation of special structures and contacts is the evolutionary way from the extrauterine type to more progressive intrauterine type of embryo development in cestodes.     

Structure and functions of the brain orexin-containing neurons

The results of investigations of the new discovered brain orexin neurons, their chemical structure, localization and functions are reviewed. The following data are described: the specifics of orexins mRNA, orexins A and B and their receptors; connections between orexin neurons and neurons from different structures of the brain and spinal cord and the participation of the orexin neuron system in the functional regulation.