Delayed effect of prenatal exposure to hypoxia on the susceptibility of rats to electric seizures

We studied the delayed effects of prenatal exposure to hypoxia on the susceptibility of rats to seizures. The later was estimated using graded electroshock. The experiments were performed in two groups of 1.5-year-old male Wistar rats. The experimental group consisted of the animals that were exposed to hypoxia on day 14 of prenatal development, and the control group consisted of the animals that developed under the normal conditions. In the rats subjected to prenatal hypoxia, seizure episodes induced by weak currents in the range of 10–40 mA and their average duration were more pronounced as compared to the control animals.     

The state of immunity in the liquidators of consequences of the Chernobyl accident with cardio-vascular diseases

The purpose of the work was research and functional reserves immunity in participants in the Chernobyl with cardiovascular disease. A Clinical Lab 49 men aged 44 to 52 years with diseases of the cardiovascular system, participated in the Chernobyl nuclear power plant in 1986 to 1988. As control used data 33 patients with similar pathology, and 16 healthy men. Researched the total number of white blood cells, lymphocytes and transfusions, the absolute number and relative CD4+ and CD8+, CD 16, CD20+, CD95+ lymphocytes peripheral blood, number mononuclear, synthesizing IL-1beta, TNF-alpha, INF-alpha, IL-4, the content of lipids and proteins, the activity of alkaline phosphatase and mieloperoksidazy in neutrophils. To assess the functional reserve immune system blood samples studied people subjected to radiation doses 0.25, 50, 1.0 Gy of in vitro and studied the reaction cytochemical indicators neutrophils before and after the radiative forcing. The liquidators not detected significant changes in the absolute number of leucocytes, but compared with control groups noted significant reduction in the absolute number of CD8+ and CD20+ lymphocytes, increased the number of cells, expression of FAS-antigen, change the number of mononuclear spontaneously synthesizing and produce cytokines, decreased maintenance of cation proteins in neutrophils. Radiation samples peripheral blood liquidators caused the same reaction cytochemical indicators of neutrophils and control groups, the compensatory and adaptive nature of the changes in the immune system, developed in response to complex factors radiation accident.     

Combinations of protein-chemical complex structures reveal new targets for established drugs

Biological networks are powerful tools for predicting undocumented relationships between molecules. The underlying principle is that existing interactions between molecules can be used to predict new interactions. Here we use this principle to suggest new protein-chemical interactions via the network derived from three-dimensional structures. For pairs of proteins sharing a common ligand, we use protein and chemical superimpositions combined with fast structural compatibility screens to predict whether additional compounds bound by one protein would bind the other. The method reproduces 84% of complexes in a benchmark, and we make many predictions that would not be possible using conventional modeling techniques. Within 19,578 novel predicted interactions are 7,793 involving 718 drugs, including filaminast, coumarin, alitretonin and erlotinib. The growth rate of confident predictions is twice that of experimental complexes, meaning that a complete structural drug-protein repertoire will be available at least ten years earlier than by X-ray and NMR techniques alone.     

Synonymous mutations in the core gene are linked to unusual serological profile in hepatitis C virus infection

The biological role of the protein encoded by the alternative open reading frame (core+1/ARF) of the Hepatitis C virus (HCV) genome remains elusive, as does the significance of the production of corresponding antibodies in HCV infection. We investigated the prevalence of anti-core and anti-core+1/ARFP antibodies in HCV-positive blood donors from Cambodia, using peptide and recombinant protein-based ELISAs. We detected unusual serological profiles in 3 out of 58 HCV positive plasma of genotype 1a. These patients were negative for anti-core antibodies by commercial and peptide-based assays using C-terminal fragments of core but reacted by Western Blot with full-length core protein. All three patients had high levels of anti-core+1/ARFP antibodies. Cloning of the cDNA that corresponds to the core-coding region from these sera resulted in the expression of both core and core+1/ARFP in mammalian cells. The core protein exhibited high amino-acid homology with a consensus HCV1a sequence. However, 10 identical synonymous mutations were found, and 7 were located in the aa(99-124) region of core. All mutations concerned the third base of a codon, and 5/10 represented a T>C mutation. Prediction analyses of the RNA secondary structure revealed conformational changes within the stem-loop region that contains the core+1/ARFP internal AUG initiator at position 85/87. Using the luciferase tagging approach, we showed that core+1/ARFP expression is more efficient from such a sequence than from the prototype HCV1a RNA. We provide additional evidence of the existence of core+1/ARFP in vivo and new data concerning expression of HCV core protein. We show that HCV patients who do not produce normal anti-core antibodies have unusually high levels of anti-core+1/ARFP and harbour several identical synonymous mutations in the core and core+1/ARFP coding region that result in major changes in predicted RNA structure. Such HCV variants may favour core+1/ARFP production during HCV infection.     

Gene flow in genetically modified wheat

Understanding gene flow in genetically modified (GM) crops is critical to answering questions regarding risk-assessment and the coexistence of GM and non-GM crops. In two field experiments, we tested whether rates of cross-pollination differed between GM and non-GM lines of the predominantly self-pollinating wheat Triticum aestivum. In the first experiment, outcrossing was studied within the field by planting "phytometers" of one line into stands of another line. In the second experiment, outcrossing was studied over distances of 0.5-2.5 m from a central patch of pollen donors to adjacent patches of pollen recipients. Cross-pollination and outcrossing was detected when offspring of a pollen recipient without a particular transgene contained this transgene in heterozygous condition. The GM lines had been produced from the varieties Bobwhite or Frisal and contained Pm3b or chitinase/glucanase transgenes, respectively, in homozygous condition. These transgenes increase plant resistance against pathogenic fungi. Although the overall outcrossing rate in the first experiment was only 3.4%, Bobwhite GM lines containing the Pm3b transgene were six times more likely than non-GM control lines to produce outcrossed offspring. There was additional variation in outcrossing rate among the four GM-lines, presumably due to the different transgene insertion events. Among the pollen donors, the Frisal GM line expressing a chitinase transgene caused more outcrossing than the GM line expressing both a chitinase and a glucanase transgene. In the second experiment, outcrossing after cross-pollination declined from 0.7-0.03% over the test distances of 0.5-2.5 m. Our results suggest that pollen-mediated gene flow between GM and non-GM wheat might only be a concern if it occurs within fields, e.g. due to seed contamination. Methodologically our study demonstrates that outcrossing rates between transgenic and other lines within crops can be assessed using a phytometer approach and that gene-flow distances can be efficiently estimated with population-level PCR analyses.     

Syntheses and crystal structures of cyano-bridged cluster-metal layered coordination polymers [Cu(dien)]3[W4Te4(CN)12] · 9H2O and [Ni(en)(NH3)]3[W4Se4(CN)12] · 7.5H2O

Two new tetrahedral tungsten cyanide cluster compounds, [Cu(dien)]₃[W₄Te₄(CN)₁₂] · 9H₂O (1) (dien=diethylenetriamine) and [Ni(en)(NH₃)]₃[W₄Se₄(CN)₁₂] · 7.5H₂O (2) (en=ethylenediamine), were synthesized by treating aqueous solutions of the saltlike cluster compound K₆[W₄Te₄(CN)₁₂] · 5H₂O/K₆[W₄Se₄(CN)₁₂] · 6H₂O with copper(II)/nickel(II) chloride in aqueous ammonia containing dien/en. The cyano-bridged layered coordination polymeric compounds were characterized by single-crystal X-ray diffraction analysis: monoclinic, space group P2₁ for 1; trigonal, space group for 2. Structures of 1 and 2 consist of infinite neutral layers of cluster components {W₄Te₄(CN)₁₂}/{W₄Se₄(CN)₁₂} connected, one another by {Cu(dien)} or {Ni(en)(NH₃)} fragments, respectively.     

Examination of the rate of peptide biosynthesis in neuroendocrine cell lines using a stable isotopic label and mass spectrometry

The biosynthesis of neuroendocrine peptides is typically examined by following the rate of appearance of a radioactive amino acid into mature forms of peptides. In the present study, we labeled cell lines with L-leucine containing 10 deuterium residues (d(10)-Leu) and used mass spectrometry to measure the biosynthetic rate of gamma-lipotropin in the AtT-20 cell line and insulin in the INS-1 cell line. After 3 h of labeling, both peptides show detectable levels of the d-labeled form in the cells and media. The relative levels of the d-labeled forms are greater in the media than in the cells, consistent with previous studies that found that newly synthesized peptides are secreted at a higher rate than older peptides under basal conditions. When AtT-20 cells were stimulated with KCl or forskolin, the ratio of d- to H-labeled gamma-lipotropin in the medium decreased, suggesting that the older peptide was in a compartment that could be released upon the appropriate stimulation. Overexpression of proSAAS in AtT-20 cells reduced the ratio of d- to H-labeled gamma-lipotropin, consistent with the proposed role of proSAAS as an endogenous inhibitor of prohormone convertase-1. Labeling with d10-Leu was also used to test whether altering the pH of the secretory pathway with chloroquine affected the rate of peptide biosynthesis. In AtT-20 cells, 30 microm chloroquine for 3 or 6 h significantly reduced the rate of formation of gamma-lipotropin in both cells and media. Similarly, INS-1 cells treated with 10, 30, or 60 microm chloroquine for 6 h showed a significant decrease in the rate of formation of insulin in both cells and media. These results are consistent with the acidic pH optima for peptide processing enzymes. Stable isotopic labeling with d10-Leu provides a sensitive method to examine the rate of peptide formation in neuroendocrine cell lines.     

Participation of the DNA-binding cytokine amphoterine in triggering the processes of tissue reparation

Author's studies and literature references indicate that the DNA-binding cytokine: amphoterine, being a non-histone component of chromatin, acts in extracellular milieu as cytokine regulating gene expression in target cells. The amphoterine effects are mediated by its interaction with the cell surface receptors including those of the final glucosiding product (RAGE), which leads to activation of the ERK and p38 MAP-kinases as well as NF-kappaB. Amphoterine prompts inflammatory response by means of activating synthesis of interleukins-1, -6 and -8 as well as tumour necrosis factors (TNF-alpha) and activates tissue regeneration by means of involvement of the precursor cells into the damage foci and induction of the cells' differentiation. These properties of amphoterine suggest that appearance of this protein in extracellular space signals of a tissue damaging.     

Changes in the free-radical state and the level of free iron during the development of drug resistance in tumor cells

The free-radical state of K562 human erythroleukemia cells changes during the development of resistance to doxorubicin, an antitumor antibiotic with prooxidant action widely used in oncology. It was found that the level of superoxide anion in the resistant cells decreased. The addition of doxorubicin to the culture medium induced a much smaller increase in O ₂ ^? generation in the resistant cells than in the sensitive cells. Again, the semiquinone-type EPR signal with a g-factor of 2.006 considerably decreased in the resistant cells grown without doxorubicin as compared with the sensitive cells under the same conditions. The EPR study has shown that the level of paramagnetic nitrosyl complexes of nonheme iron in the resistant cells decreased, which indicates that the content of free nonheme iron declined in development of drug resistance. In addition, we have found with the use of RT-PCR that the level of mRNA of the transferrin receptor decreased in the resistant cells. The data suggest that the suppression of free-radical processes during the development of resistance of K562 cells to doxorubicin is a coordinated redox-dependent adaptive response.     

Zinc ions stimulate the cooperative RNA binding of hordeiviral gammab protein

A small regulatory gammab protein of the Poa semilatent hordeivirus (PSLV) contains two zinc finger-like motifs separated by a basic motif in the N-terminal part and a C-terminal coiled-coil motif. Interactions of the recombinant PSLV gammab protein and its mutants with various RNAs (ssRNA, dsRNA, ssRNA oligonucleotides) and ssDNA were studied in gel-shift assays. The results demonstrated that zinc ions are essential for effective nucleic-acid-binding activity of the gammab protein, suggesting the important role of zinc finger motifs in these interactions. Deletion of the C-proximal coiled-coil region did not affect highly cooperative RNA-protein binding, indicating that the N-terminal part of the protein contributes to the protein-protein interactions needed for the protein-RNA cooperativity.