Persistent toxic substances in the muscles and liver of the pacific walrus Odobenus rosmarus divergens Illiger, 1815 from the Bering Sea

This study reports data on the contents of organochlorine pesticides and heavy metals in the muscles and livers of eight individuals (five males and three females) of the Pacific walrus Odobenus rosmarus divergens Illiger, 1815, which were captured in the summer of 2011 in Mechigmensky Bay of the Bering Sea. Pesticides, namely α-, β-, and γ-isomers of hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT) and its metabolites dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethylene (DDE), as well as the heavy metals Cd, Pb, and Hg were found in all samples studied. The total concentration of organochlorine pesticides in the muscles varied from 200 to 5700 ng/g lipid weight and in the liver from 4900 to 90300 ng/g lipid weight. The concentrations of cadmium, lead, and mercury were 0.04–6.7, 0.13–0.76, and 0.03–0.40 μg/g dry weight, respectively. On the whole, the contents of organochlorine pesticides and heavy metals in the organs of the Pacific walrus were lower compared to those in marine mammals from other regions of the World Ocean.     

Functioning of the mitochondrial ATP-dependent potassium channel in rats varying in their resistance to hypoxia. Involvement of the channel in the process of animal’s adaptation to hypoxia

The mechanism of tissue protection from ischemic damage by activation of the mitochondrial ATP-dependent K⁺ channel (mitoK_ATP) remains unexplored. In this work, we have measured, using various approaches, the ATP-dependent mitochondrial K⁺ transport in rats that differed in their resistance to hypoxia. The transport was found to be faster in the hypoxia-resistant rats as compared to that in the hypoxia-sensitive animals. Adaptation of animals to the intermittent normobaric hypoxia increased the rate of transport. At the same time, the intramitochondrial concentration of K⁺ in the hypoxia-sensitive rats was higher than that in the resistant and adapted animals. This indicates that adaptation to hypoxia stimulates not only the influx of potassium into mitochondria, but also K⁺/H⁺ exchange. When mitoK_ATP was blocked, the rate of the mitochondrial H₂O₂ production was found to be significantly higher in the hypoxia-resistant rats than that in the hypoxia-sensitive animals. The natural flavonoid-containing adaptogen Extralife, which has an evident antihypoxic effect, increased the rate of the mitochondrial ATP-dependent K⁺ transport in vitro and increased the in vivo tolerance of hypoxia-sensitive rats to acute hypoxia 5-fold. The involvement of the mitochondrial K⁺ transport in the mechanism of cell adaptation to hypoxia is discussed.     

外源性磷酸肌酸对重度窒息新生儿血清S-100B 蛋白 及NSE 水平的影响

目的:探讨外源性磷酸肌酸对重度窒息新生儿血清S-100B蛋白和特异性神经元烯醇化酶含量(NSE)的影响。方法:重度窒息的新生儿40例,随机分为两组,常规治疗组21例,给予一般治疗(氧疗、支持、对症)和胞二磷胆碱治疗。磷酸肌酸治疗组19例,在常规治疗基础上,生后12h内给予磷酸肌酸治疗1g/d),另外同期住院的新生儿湿肺和黄疸患儿14例为正常对照组。均与生后48h和生后10天取血检测血清S-100B蛋白和NSE含量。并于生后第14天进行新生儿行为神经测定(NBNA评分)。结果:磷酸肌酸治疗组和常规治疗组患儿生后48h血清S-100B蛋白和NSE含量无显著差异(※P>0.05,※P>0.05),与正常对照组比较差异具有显著性(△P<0.05,△P<0.05),生后10天血清S-100B和NSE含量在常规治疗组患儿和磷酸肌酸组相比具有显著差异,磷酸肌酸治疗组两者明显下降(※P<0.05,※P<0.05)。生后三周的行为神经评估(NBNA评分)<35分者所占百分比磷酸肌酸治疗组27%与常规治疗组组53%比较,差异均具有显著性意义(x2=6.112,※P<0.05)。结论:磷酸肌酸用于治疗新生儿缺氧缺血性脑病能够改善脑的能量代谢,降低脑损伤的程度,改善神经行为,降低致残率。     

Peptidoglycan recognition protein tag7 forms a cytotoxic complex with heat shock protein 70 in solution and in lymphocytes

The peptidoglycan recognition protein Tag7 is shown to form a stable 1:1 complex with the major stress protein Hsp70. Neither protein is cytotoxic by itself, but their complex induces apoptotic death in several tumor-derived cell lines even at subnanomolar concentrations. The minimal part of Hsp70 needed to evoke cytotoxicity is residues 450-463 of its peptide-binding domain, but full cytotoxicity requires its ATPase activity; remarkably, Tag7 liberated from the complex at high ATP is not cytotoxic. The Tag7-Hsp70 complex is produced by tag7-transfected cells and by lymphokine-activated killers, being assembled within the cell and released into the medium through the Golgi apparatus by a mechanism different from the commonly known granule exocytosis. Thus, we demonstrate how a heat shock protein may perform functions clearly distinct from chaperoning or cell rescue and how peptidoglycan recognition proteins may be involved in innate immunity and anti-cancer defense.     

Cadmium accumulation in organs of the scallop Mizuhopecten yessoensis--I. Activities of phosphatases and composition and amount of lipids

Maintenance of Mizuhopecten yessoensis in water with 0.5 mg Cd/l for 60 days increased Cd concentration in the mantle and ovaries about 200 times, in gills 70 times and hepatopancreas 20 times. Alkaline phosphatase activity was inhibited in all organs except the hepatopancreas after a 1-month exposure to Cd and became equal to the control in all the organs after 2 months exposure. Molluscs transferred to flowing water showed a considerable decrease in the activity of alkaline and acid phosphatases. The activity of both acid phosphatase and Mg2+-ATPase decreased in all the organs of experimental molluscs after exposure to Cd. The amount of phospholipids and cholesterol in the organs of control and experimental molluscs did not essentially differ.     

Novel Genes Associated with the Development of Carotid Paragangliomas

Molecular Biology - Carotid paragangliomas (CPGLs) are rare neuroendocrine tumors of the head and neck. “Germline” and somatic mutations in a number of genes were shown to be associated...     

The role of S100A4 protein in anticancer cytotoxicity: its presence is required on the surface of CD4+CD25+PGRPs+S100A4+ lymphocyte and undesirable on the surface of target cells

S100A4 is a Ca²⁺-binding protein that performs an important role in metastasis. It is also known for its antitumor functions. S100A4 is expressed by a specialized subset of CD⁴⁺CD²⁵⁺ lymphocytes and is present on those cell's membranes along with peptidoglycan recognition proteins (PGRPs). There, by interacting with major heat shock protein Hsp70, S100A4 plays an important cytotoxic role. The resulting stably formed complex of PGRPs, S100A4 and Hsp70 is required for the identification and binding between a lymphocyte and a target cell. Here, we investigated the S100A4 functions in CD⁴⁺CD²⁵⁺PGRPs⁺S100A4⁺ lymphocyte cytotoxicity against target cells. We demonstrated that those lymphocytes do not form a stable complex with the tumor target cells that themselves have S1004A on their surface. That observation can be explained by our finding that S100A4 precludes the formation of a stable complex between PGRPs, S100A4 (on the lymphocytes’ surface), and Hsp70 (on the target cells’ surface). The decrease in S100A4 level in CD⁴⁺CD²⁵⁺PGRPs⁺S100A4⁺ lymphocytes inhibits their cytotoxic activity, while the addition of S100A4 in the medium restores it. Thus, the resistance of target cells to CD⁴⁺CD²⁵⁺PGRPs⁺ S100A4⁺ lymphocyte cytotoxicity depends on their S100A4 expression level and can be countered by S100A4 antibodies.     

Ecotoxicological assessment of several estuarine zones in the south of Primorsky Krai

A complex ecotoxicological assessment of several estuarine zones of the Razdol’naya, Barabashevka, Ryazanovka, and Gladkaya rivers in Amur Bay, and the Artyomovka and Sukhodol rivers in Ussyry Bay was carried out in 2007 and 2008. Bottom sediments in the estuary of the Kievka river were collected in 2009. The content of petroleum hydrocarbons was determined in the water and bottom sediments of riverine and marine sectors of estuaries and the total toxicity of bottom sediments was tested with the use of mysids. Bottom sediments from a small river on Reineke Island, in which the concentrations of primary pollutants corresponded to the background values for the entire Peter the Great Bay, were used as a control. The content of organochlorine pesticides in the muscles and liver of the Redeye Eastern Redfin (Tribolodon brandtii) was determined and molecular biomarkers of oxidative stress in organs of the Redlip Mullet (Liza haematocheila) analyzed. The amount of wastewater and pollutants flowing into Amur Bay and Ussyry Bay with some of the rivers was estimated. The correlation coefficient between the toxicity of bottom sediments and the petroleum hydrocarbons content in them was found. The higher sediment toxicity in the riverine zone, as compared to the marine zone, proves the concept of the “river-sea” biogeochemical barrier.