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We report here a study examining the effects of acute normobaric hypoxia in the early postnatal period of development (postnatal day 2) on learning ability and the expression of GABAB receptors in the neocortex (medial prefrontal cortex) of adolescent rats (postnatal days 55–60) and also addressing the possibility of correcting identified disorders with the Russian-made drug salifen, a GABA derivative. Perinatal hypoxia has been shown to impair the formation and retention of memory traces in the novel object recognition and conditioned passive avoidance reflex tests and to reduce spatial learning ability in the Morris water maze test. Analysis of Western blot results revealed an increase in the quantity of GABAB receptor protein in the medial prefrontal area of the neocortex of rats exposed to perinatal hypoxia. Administration of salifen 15 mg/kg for 14 days after exposure to hypoxia improved the cognitive abilities of rats and normalized the level of GABAB receptor protein expression in the medial prefrontal cortex of rats. The results obtained here are of interest for solving an applied challenge in neonatology – the search for effective pharmacological correction of the sequelae of perinatal hypoxia. [ABSTRACT FROM AUTHOR]

We study Late Jurassic thrusting of the Archean craton basement over Jurassic sediments in Siberia, with the Khamar-Daban terrane as a rigid indenter. The study focuses on deformation and secondary mineralization in Archean and Mesozoic rocks along the thrusting front and the large-scale paleotectonic thrust structure. The pioneering results include the inference that the Angara, Posol'skaya, and Tataurovo thrusts are elements of the Angara-Selenga imbricate fan thrust system and a 3D model of its Angara branch. The history of the Angara-Selenga thrust system consists of three main stages: (I) detachment and folding of the basement under the Jurassic basin and low-angle synclinal and anticlinal folding in the sediments in a setting of weak compression; (II) brecciation and mylonization under increasing shear stress that split the Sharyzhalgai basement inlier into several blocks moving in different directions; formation of an imbricate fan system of thrust sheets that shaped up the thrusting front geometry, with a greater amount of thrusting in the front because of the counter-clockwise rotation of the Sharyzhalgai uplift; (III) strike-slip and normal faulting associated with the origin and evolution of the Baikal rift system, which complicated the morphology of the thrust system. [ABSTRACT FROM AUTHOR]

Glucose ixidase from Penicillium vitale was immobilized in a 2-hydroxyethyl methacrylate (HEMA) gel containing 0.3 to 2% of methacrylic acid (MAA) or MAA neutralized by allylamine (AA). Depending on the MAA quantity of MAA in the gel, the thermal irreversible inactivation (k ) constants of the immobilized enzymes sharply decrease at gel concentrations higher than 29 to 50% at pH 5.8. A 220- to 250-fold decrease of k was observed in 60 to 80% gel. The inactivation rate of enzyme in HEMA gel also decreases considerably under the action of urea. Over the range of pH 5.0 to 9.0 the k of the native enzyme depends on pH by a degree of 2.1, and of the immobilized enzyme, 0.3 to 0.55. Over the pH range of 5.2 to 5.7, k of the native and immobilized enzymes are approximate, whereas at pH 8 and over the difference between k values exceeds four orders of magnitude. The activity dependence of the immobilized enzyme on pH is shifted two units to the alkaline region. This shift depends on the ionic strength of the solution. This dependence is best reflected in the high gel concentrations. A mechanism of enzymes stabilization in the concentrated HEMA gel is discussed. [ABSTRACT FROM AUTHOR]

We present the first high-resolution determination of transcriptome architecture in the priority pathogen Acinetobacter baumannii. Pooled RNA from 16 laboratory conditions was used for differential RNA-seq (dRNA-seq) to identify 3731 transcriptional start sites (TSS) and 110 small RNAs, including the first identification in A. baumannii of sRNAs encoded at the 3' end of coding genes. Most sRNAs were conserved among sequenced A. baumannii genomes, but were only weakly conserved or absent in other Acinetobacter species. Single nucleotide mapping of TSS enabled prediction of -10 and -35 RNA polymerase binding sites and revealed an unprecedented base preference at position +2 that hints at an unrecognized transcriptional regulatory mechanism. To apply functional genomics to the problem of antimicrobial resistance, we dissected the transcriptional regulation of the drug efflux pump responsible for chloramphenicol resistance, craA. The two craA promoters were both down-regulated >1000-fold when cells were shifted to nutrient limited medium. This conditional down-regulation of craA expression renders cells sensitive to chloramphenicol, a highly effective antibiotic for the treatment of multidrug resistant infections. An online interface that facilitates open data access and visualization is provided as 'AcinetoCom' (http://bioinf.gen.tcd.ie/acinetocom/).

Gonadal hormones have been well-known to affect brain regions known to be involved in the modulation of mood and affective-related behavior. Prenatal stress might alter hypothalamic-pituitary-gonadal axis, it could be a target for development of affective-related disorders in male offspring. The present study was designed to examine an anxiety-like behavior in the adult male offspring with low levels of endogenous androgens delivered from pregnant dams exposed to prenatal stress from gestation day 15 to gestation day 19. The non-stressed and prenatally stressed intact, gonadectomized (GDX) and GDX male offspring treated with oil solvent or testosterone propionate (TP, 0.5 mg/kg, s.c., 14 days, once daily) were used in all experiments. Anxiety-like behavior was assessed in the elevated plus maze (EPM) and the open field test (OFT), respectively. Also, testosterone levels in the blood serum were measured in all experimental groups of offspring. Prenatally stressed GDX offspring demonstrated a significant decrease for time spent into the open arms and increase for time spent into the closed arms as compared to the non-stressed offspring. Administration of TP to the prenatally stressed GDX offspring resulted in a more markedly decrease of the time spent into the open arms and significantly raised the time spent into the closed arms as compared to the non-stressed GDX offspring treated with TP, non-stressed/prenatally stressed GDX offspring. Prenatally stressed GDX offspring showed a significant increase of crossing, rearing, grooming and defecation as compared to the prenatally stressed control offspring. On the contrary, administration of TP to the prenatally stressed GDX offspring significantly decreased crossing behavior, frequency of rearing and grooming behavior as compared to the non-stressed GDX offspring treated with TP, non-stressed/prenatally stressed GDX offspring. Prenatally stressed GDX offspring demonstrated a significant decrease of testosterone levels as compared to the non-stressed/prenatally stressed intact offspring, as well as non-stressed GDX offspring. Administration of TP significantly increased testosterone levels when prenatally stressed GDX offspring were compared with the prenatally stressed intact offspring, non-stressed/prenatally stressed GDX offspring. Thus, the results of the study clearly suggest that gonadectomy and TP supplementation profoundly changed an anxiety-related behavior in prenatally stressed male offspring in the EPM. Our current findings suggest that androgen deficiency in the prenatally stressed male offspring produces the high anxiety level and induces a marked anxious-like state. TP supplementation provokes development of profoundly anxious-like state in the prenatally stressed male offspring, Furthermore, this is the first study to show anxiogenic-like effect of TP administration on anxiety-related states in prenatally stressed male offspring with androgen deficiency.