Electron microscopic characteristics and polypeptide composition of the nuclear matrix of liver cells in mice with autoimmune disease

A study was made of the ultrastructure and polypeptide composition of liver cell nuclear matrix of F1NZB/NZW hybrid mice imitating human systemic Lupus erythematosus. Electron microscopy reveals enlargement in fibrous lamina diameter and increase in pore complex density up to the age of 8-9 months. In the terminal stages of the disease (12-13 months of age) a gradual attenuation of the intranuclear matrix and disappearance of pore complexes is observed along with a segregation and subsequent fragmentation of residual nucleoli which results eventually in the general degradation of the nuclear matrix. 30-35 polypeptide bands with molecular weight from 200 to 10 kD are revealed in polyacrylamide gel electrophoresis of the liver cell nuclear matrix of hybrid mice. Several protein bands in the high molecular weight region of 200-150 kD are strongly enhanced, and a triplet with molecular weight 70-60 kD is distinctly visible. The results obtained are interpreted as an indication of a protecting cellular reaction against antinuclear autoantibodies in the earlier stages, and a degradation of the nuclear matrix in terminal stages of the disease. It is supposed that the electron microscopic and electrophoretic patterns of the nuclear matrix indicate an accumulation of collagenous proteins.     

The effect of gamma irradiation on the structure and enzymatic activity of the nuclear membrane of the liver in pregnant rats and their embryos]

Morphological and biochemical investigations of pregnant rats and embryo liver cell nuclei after in vivo irradiation in the doses of 1 and 2 Gr revealed their high radiosensitivity at all stages of gestation and embryonal development. At damaging effect of radiation, we managed to observe sharp accumulation of products of lipid peroxide oxidation and suppression of the activities of such enzymes as cytochrome-c-oxidase, NAD.N-cytochrome-c-reductase, ATPase and RNAase in liver nuclei of pregnant rats and embryos. The changes of such a kind are shown to intensify with the increasing of irradiation doses. The most profound inhibition of the activities of these enzymes in liver nuclei of embryos irradiated in utero was observed during the period of organogenesis (the 13th day of the development) and in fetal period of embryogenesis (the 17th day of the development), as well as at the 13th and 17th day of gestation. The morphological data also demonstrate the high level of cell nucleus sensitivity to the action of radiation during gestation and embryogenesis.     

Photo‐identification matches of humpback whales (Megaptera novaeangliae) from feeding areas in Russian Far East seas and breeding grounds in the North Pacific

Humpback whales migrate seasonally from high latitude feeding areas to lower latitude breeding areas for mating and calving. In 2004–2006, a North Pacific basin‐wide study called SPLASH was conducted as an international collaboration among various groups of researchers. The Russian Far East consists of multiple high latitude feeding areas and during SPLASH, 102 whales were identified and compared to catalogs from breeding areas. Our goal in this study was to further investigate the migratory destinations of whales from the Russian Far East using a total of 1,459 photographs of whales identified from 2004 to 2014. We compared the latest Russian catalog with the SPLASH catalog from wintering areas (2004–2006) and with two additional regional catalogs from Okinawa (1989–2006) and the northern Philippines (2000–2006). We found a total of 152 matches: 106 with Asian, 35 with Hawaiian, and 11 with Mexican breeding grounds. The match rate was higher in mainland Kamchatka and consisted mostly of whales from the Asian breeding ground. In the Commander Islands, the proportion of whales from Asia was twice that of Hawaii and six times higher than Mexico. The total match rate was low, supporting the hypothesis of some undiscovered humpback whale breeding location in the North Pacific.     

Synthesis and analysis of conformationally restricted analogs of peptide inhibitors of the angiotensin-converting enzyme

To investigate conformations of peptide inhibitors of the angiotensin-converting enzyme in the enzyme-inhibitor complex, the synthesis, studies of inhibitory activity, and conformational calculations of analogues of bradykinin-potentiating peptides with N-methylalanine or D-alanine in place of L-proline or L-alanine residues have been carried out. All the analogues showed a sharp decrease of inhibitory activity in comparison with the natural peptides, that might be considered as an indirect confirmation of the earlier proposed "conformation of inhibition" of the above-mentioned peptides.     

马鞍菌属新种和新记录Ⅱ.

本文报道了近年来在中国发现的马鞍菌属 Heluella 的3个新种,即蛟河马鞍菌H.Jiaohensis,吉林马鞍菌 H.jilinensis 和新疆马鞍菌 H.xinjiangensis;3个新记录种即肋盖马鞍菌 H.costifera,长孢马鞍菌 H.oblongispora 和灰黑马鞍菌 H.rivularis。此外由于亚梭孢马鞍菌 H.subfusispora 的模式标本于1984年在火中被毁,因此作者在另一份标本(HMAS 30483)的基础上为其标定了新模式(Neotype)。     

Usage of monophonic and biphonic calls by free-ranging resident killer whales (Orcinus orca) in Kamchatka, Russian Far East

Killer whale discrete calls include types containing an overlapping high-frequency component (biphonic calls) and types without an overlapping high-frequency component (monophonic calls). In the resident killer whales of the Northeast Pacific, biphonic discrete calls exhibit higher source levels than monophonic calls, which suggests different active space and consequently different functions for monophonic and biphonic call types. In this study we investigate the potential communicative functions of monophonic and biphonic discrete calls produced by killer whales from Kamchatka (Northwest Pacific). We analyze how the usage of these calls depends on the number of pods present in the area and type of activity. Our results show that the usage of monophonic and biphonic calls in Kamchatkan killer whales depends on the number of pods in the area and is less dependent on the type of activity. Biphonic calls are more common when more than one pod is present in the area and could therefore function as markers of pod and matriline affiliation, serving mainly as cohesion signals. Monophonic calls dominated the vocalizations when a single pod was present, while in the presence of more than one pod both categories were used in equal proportions.     

Sensitivity to lysis by natural killers depends on the integrity of lipid rafts in plasma membrane of transformed cells

The present work focused on the role of cholesterol-rich membrane microdomains (rafts) in cellular mechanisms of innate immunity and anticancer defence. The lytic effect of natural killers (NK) was examined in dependence on cholesterol content in transformed target cells. In the current study, K562 human erythroleukaemia cells were the targets. K562 cells were treated with methyl-beta-cyclodextrin (MbCD) to deplete membrane cholesterol that was verified by enzymatic method. With the use of 3H-uridine test, NK (mouse splenocytes) cytotoxity was estimated under various conditions, specifically, after incubation of K562 cells with MbCD or inactive analog alpha-cyclodextrin. The data obtained show that cholesterol-depleting treatment (2.5 or 5 mM MbCD) of target cells results in full loss of their sensitivity to NK lysis. The effect is likely to be due to disintegrity of lipid rafts that is critically dependent on the level of membrane cholesterol. Visualization of cell surface changes by fluorescent labeling of ganglioside GM1 confirmed our conclusions.