Occurrence of amitotic division of trophoblast cell nuclei in blastocysts of the western spotted skunk (Spilogale putorius latifrons)

A cytogenetic examination of spreaded cells of diapausing and early activated blastocysts obtained from 7 female western spotted skunks was performed. Mitosis was not observed in 1626 cells obtained from 9 diapausing blastocysts; however, 12 (1.5%) figures of diploid mitosis were seen in 851 cells from 5 early activated embryos. Diameter of the cell nuclei varied from 4 to 29 microm during diapause, and from 5 to 40 microm in activated blastocyst, and the heterogeneity in nuclear size was significantly different between diapausing and activated embryos (P<0.01). About 80% of nuclei from diapausing blastocysts measured 9 to 16 microm, whereas a similar percentage of nuclei from activated blastocysts ranged from 15 to 27 microm. Many enlarged nuclei exhibited morphological features characteristic of mammalian polytene (i.e. endopolyploid with polytenic organization of chromosomes) trophoblast cells. The number of silver stained nucleoli in all the nuclei did not exceed 2, which corresponds to the number of nucleolus organizers in the diploid karyotype in this species of skunk and suggests the polytene organization of chromosomes in enlarged nuclei. About 10% of large interphase nuclei were observed to undergo amitosis, i.e. direct division by constriction. The resulting nuclear fragments in diapausing blastocysts usually had normal morphology and active nucleoli. In activated embryos, nearly 15% of amitotically divided nuclei appeared to be dividing into fragments of unequal size, one of which had normal cell nuclear morphology and extremely large silver positive nucleoli, and the other fragment exhibited signs of cell death. We interpret these data as indicating that 1) amitotic division of trophoblast endopolyploid cell nuclei in the skunk blastocysts may generate new trophoblast cells which contribute to increased cell number during both diapause and activation stages, and 2) activation of blastocysts after diapause is related to the production of trophoblast cells with enhanced synthetic capabilities.     

Genetic Modulation of Lipid Profiles following Lifestyle Modification or Metformin Treatment: The Diabetes Prevention Program

Weight-loss interventions generally improve lipid profiles and reduce cardiovascular disease risk, but effects are variable and may depend on genetic factors. We performed a genetic association analysis of data from 2,993 participants in the Diabetes Prevention Program to test the hypotheses that a genetic risk score (GRS) based on deleterious alleles at 32 lipid-associated single-nucleotide polymorphisms modifies the effects of lifestyle and/or metformin interventions on lipid levels and nuclear magnetic resonance (NMR) lipoprotein subfraction size and number. Twenty-three loci previously associated with fasting LDL-C, HDL-C, or triglycerides replicated (P = 0.04–1×10⁻¹⁷). Except for total HDL particles (r = −0.03, P = 0.26), all components of the lipid profile correlated with the GRS (partial |r| = 0.07–0.17, P = 5×10⁻⁵–1×10⁻¹⁹). The GRS was associated with higher baseline-adjusted 1-year LDL cholesterol levels (β = +0.87, SEE±0.22 mg/dl/allele, P = 8×10⁻⁵, P _interaction = 0.02) in the lifestyle intervention group, but not in the placebo (β = +0.20, SEE±0.22 mg/dl/allele, P = 0.35) or metformin (β = −0.03, SEE±0.22 mg/dl/allele, P = 0.90; P _interaction = 0.64) groups. Similarly, a higher GRS predicted a greater number of baseline-adjusted small LDL particles at 1 year in the lifestyle intervention arm (β = +0.30, SEE±0.012 ln nmol/L/allele, P = 0.01, P _interaction = 0.01) but not in the placebo (β = −0.002, SEE±0.008 ln nmol/L/allele, P = 0.74) or metformin (β = +0.013, SEE±0.008 nmol/L/allele, P = 0.12; P _interaction = 0.24) groups. Our findings suggest that a high genetic burden confers an adverse lipid profile and predicts attenuated response in LDL-C levels and small LDL particle number to dietary and physical activity interventions aimed at weight loss.     

Induction in vivo of specific T suppressors in mice of mutant lines H-2KbT

The differences in the generation of specific suppressor T cells (SSTC) against H-2Kb wild type were investigated in H-2Kbm1, H-2Kbm3 and H-2Kbm4 mutants. Anti-Kb SSTC were produced only by bm3 mutant and F1(BALB/c X bm3) hybrid. T-cell nature of SSTC of bm3 mutant was confirmed by anti-Thy 1.2 monoclonal antibodies described in the same study.     

Selection of the conodont Idiognathodus simulator (Ellison) as the event marker for the base of the global Gzhelian Stage (Upper Pennsylvanian, Carboniferous)

Studies carried out for more than 10 years by the Task Group to establish GSSPs at the base of the Moscovian–Kasimovian and Kasimovian–Gzhelian boundaries have resulted in the proposal that the level at which the conodont species Idiognathodus simulator (Ellison, 1941) first appears be selected to mark the base of the Gzhelian Stage. This expands this eastern European chronostratigraphic unit to a global scale.I. simulator (sensu Barrick et al., 2008) has been identified so far in Midcontinent and eastern North America, the Moscow and Donets basins and southern Urals of eastern Europe, and in south-central China. Correlation of this level based on this species and other conodont species can be reinforced in some areas by ammonoid and fusulinid data.     

Novel efficient promoter of the mitochondrial porin,voltage-dependent anion channel (VDAC), in the genome of the <Emphasis Type="Italic">Yarrowia lipolytica</Emphasis> yeast

This article presents the characteristics of the highly inducible promoter of the gene encoding the mitochondrial porin, the voltage-dependent anion channel (VDAC). This promoter is recommended for use in new genetic constructs both in basic research for assessing the adaptive strategy of lower eukaryotes under adverse conditions and in designing new highly competitive transformants producing economically important compounds (proteins, lipids, and organic acids) on its basis.     

A New Recombinant Strain of <Emphasis Type="Italic">Yarrowia lipolytica</Emphasis> Producing Encapsulated Phytase from <Emphasis Type="Italic">Obesumbacterium proteus</Emphasis>

A new recombinant strain of Yarrowia lipolytica synthesizing encapsulated highly thermostable phytase of Obesumbacterium proteus, which is recommended for use as a premix component of feed compositions in animal husbandry, was obtained.     

Carbohydrate Spectrum of Extremophilic Yeasts <Emphasis Type="Italic">Yarrowia lipolytica</Emphasis> under pH Stress

Alterations in the concentrations of cell cytosol carbohydrates of polyextremophilic yeasts Yarrowia lipolytica under stresses of diverse nature were observed. Under pH stress, mannitol was the main storage carbohydrate (up to 89% of the total cytosol carbohydrates), while arabitol, glucose, and inositol were present in insignificant amounts (3 to 6%). Experiments with inhibition of de novo mannitol synthesis by bis(p-nitrophenyl) disulfide revealed that the cytoprotective effect of mannitol was most noticeable in the cells grown under acidic conditions (pH 4.0), while the role of catalase and superoxide dismutase, the enzymes of the first line of antioxidant protection, increased under alkaline conditions (pH 9.0). The constitutively high mannitol content in Y. lipolytica cells was hypothesized to be a part of the core mechanism of stress resistance in this yeast species.     

The construction and use of inosine-containing primers for searching for and identifying the genes of insecticidal crystal proteins in Bacillus thuringiensis]

The specific to 3 types of Cry genes primers containing inosine were constructed to find crystal insecticidal protein Bacillus thuringiensis genes using PCR. A number of new B. thuringiensis strains isolated in Ukraine were investigated using these PCR primers. As a results, Cry genes were found, some of them were identified and demonstrated high homology to Cry1Ba2 and Cry1Bc genes.