p53和顺铂对Wnt通路抑制剂FrpHE的表达作用

将携带p53基因的复制缺陷型腺病毒载体Adp53导入到p53完全缺失的人肝癌细胞株中,培养人肿瘤细胞,并分别加入5μmol/L顺铂(Pt)作用24 h,以RT-PCR技术检测FrpHE mRNA的表达作用,以流式细胞术检测Adp53的转基因情况和β-catenin的改变为功能指标评价Wnt通路的变化.FrpHE mRNA表达水平在转染Adp53和作用Pt 24 h后即有明显升高,在人大肠癌细胞和人神经胶质瘤细胞中,未见FrpHE mRNA表达.β-catenin表达水平逐渐下降.提示外源性物质p53和顺铂能明显诱导FrpHE的表达,进而产生抑制Wnt通路的作用.     

Unravelling developmental disregard in children with unilateral cerebral palsy by measuring event-related potentials during a simple and complex task

Background

In a subset of children with unilateral Cerebral Palsy (CP) a discrepancy between capacity and performance of the affected upper limb can be observed. This discrepancy is known as Developmental Disregard (DD). Though the phenomenon of DD has been well documented, its underlying cause is still under debate. DD has originally been explained based on principles of operant conditioning. Alternatively, it has been proposed that DD results from a diminished automaticity of movements, resulting in an increased cognitive load when using the affected hand. To investigate the amount of involved cognitive load we studied Event-Related Potentials (ERPs) preceding task-related motor responses during a single-hand capacity and a dual-hand performance task. It was hypothesised that children with DD show alterations related to long-latency ERP components when selecting a response with the affected upper limb, reflecting increased cognitive load in order to generate an adequate response and especially so within the dual-hand task.

Methods

Fifteen children with unilateral CP participated in the study. One of the participants was excluded due to major visual impairments. Seven of the remaining participants displayed DD. The other seven children served as a control group. All participants performed two versions of a cue-target paradigm, a single-hand capacity and a dual-hand performance task. The ERP components linked to target presentation were inspected: the mid-latency P2 component and the consecutive long-latency N2b component.

Results

In the dual-hand performance task children with DD showed an enhancement in mean amplitude of the long-latency N2b component when selecting a response with their affected hand. No differences were found regarding the amplitude of the mid-latency P2 component. No differences were observed regarding the single-hand capacity task. The control group did not display any differences in ERPs linked to target evaluation processes between both hands.

Conclusion

These electrophysiological findings show that DD is associated with increased cognitive load when movements are prepared with the affected hand during a dual-hand performance task. These findings confirm behavioural observations, advance our insights on the neural substrate of DD and have implications for therapy.     

Oxidation of sulfur-containing substrates by an association of acidophilic chemolithotrophic microorganisms

Quantitative and qualitative changes in the content of elements in the solid and liquid phases occurred as the pulp moved through reactors during biooxidation of an ore flotation concentrate. The association of microorganisms were adapted for utilizing sulfur-containing substrates; however, the rate of their oxidation was insufficient, which led to an increase in the amount of sodium cyanide required for gold recovery. The replacement of one-fourth of the liquid phase of the pulp (density, 13%) with a mineral medium without an energy source, the fractional addition of FeSO₄ · 7H₂O (1 g/l per day), and the improvement of pulp aeration made it possible to increase the content of SO ₄ ^2? by 80.7, 86.2, and 58.5%, respectively. When one-fourth of the liquid phase of the pulp (density, 24%) was replaced with a mineral medium without an energy source, the rate of additional oxidation of sulfide minerals increased, which increased the efficiency of gold extraction into solution and gold recovery on charcoal by 3.4 and 3.6%, respectively, and reduced sodium cyanide consumption by 3 kg/ton.     

Effect of legume seed exudates on the formation of Rhizobium-legume symbiosis

The effect of exudates from germinating lupine and soybean seeds on the development of legumerhizobia symbiosis in the same plants was studied. Treatment with the exudates increased the nodulation activity of Bradyrhizobium sp. (Lupinus) and slowed down the formation of nodules by Bradyrhizobium japonicum 634b. The number of nodules produced by B. japonicum 631 on soybean roots increased when the strain was treated with soybean exudate at a lower concentration. The exudates differently affected nodulation on the primary and secondary roots of the host plant. The formation of symbiosis by B. japonicum 631 incubated with legume seed exudates increased the weight of the green parts of plants at the bud stage.     

Endometrial claudin-4 and leukemia inhibitory factor are associated with assisted reproduction outcome

Background  

Claudin-4 (CLDN4) is one of several proteins that act as molecular mediators of embryo implantation. Recently, we examined immunolabeling of leukemia inhibitory factor (LIF) in the endometrial tissue of 52 IVF patients, and found that LIF staining intensity was strongly correlated with successful pregnancy initiation. In the same set of patients, we have now examined endometrial CLDN4 expression, to see how expression intensity may vary with LIF. We examined CLDN4 in the luteal phase of the menstrual cycle, immediately preceding IVF treatment. Our aim was to compare expression of LIF and CLDN4 in the luteal phase, and document these patterns as putative biomarkers for pregnancy.     

Mechanism of cyanide and thiocyanate decomposition by an association of Pseudomonas putida and Pseudomonas stutzeri strains

The intermediate and terminal products of cyanide and thiocyanate decomposition by individual strains of the genus Pseudomonas, P. putida strain 21 and P. stutzeri strain 18, and by their association were analyzed. The activity of the enzymes of nitrogen and sulfur metabolism in these strains was compared with that of the collection strains P. putida VKM B-2187^T and P. stutzeri VKM B-975^T. Upon the introduction of CN⁻ and SCN⁻ into cell suspensions of strains 18 and 21 in phosphate buffer (pH 8.8), the production of NH ₄ ⁺ was observed. Due to the high rate of their utilization, NH₃, NH ₄ ⁺ , and CNO⁻ were absent from the culture liquids of P. putida strain 21 and P. stutzeri strain 18 grown with CN⁻ or SCN⁻. Both Pseudomonas strains decomposed SCN⁻ via cyanate production. The cyanase activity was 0.75 μmol/(min mg protein) for P. putida strain 21 and 1.26 μmol/(min mg protein) for P. stutzeri strain 18. The cyanase activity was present in the cells grown with SCN⁻ but absent in cells grown with NH ₄ ⁺ . Strain 21 of P. putida was a more active CN⁻ decomposer than strain 18 of P. stutzeri. Ammonium and CO₂ were the terminal nitrogen and carbon products of CN⁻ and SCN⁻ decomposition. The terminal sulfur products of SCN⁻ decomposition by P. stutzeri strain 18 and P. putida strain 21 were thiosulfate and tetrathionate, respectively. The strains utilized the toxic compounds in the anabolism only, as sources of nitrogen (CN⁻ and SCN⁻) and sulfur (SCN⁻). The pathway of thiocyanate decomposition by the association of bacteria of the genus Pseudomonas is proposed based on the results obtained. Original Russian Text ? N.V. Grigor’eva, T.F. Kondrat’eva, E.N. Krasil’nikova, G.I. Karavaiko, 2006, published in Mikrobiologiya, 2006, Vol. 75, No. 3, pp. 320–328.     

Ten new microsatellite markers for the buttonwood mangrove (Conocarpus erectus L., Combretaceae)

We present 10 microsatellite markers for the buttonwood mangrove, Conocarpus erectus, a wide-range mangrove associate species. Polymorphism was assessed among individuals from six different populations along the Pacific Coast of Mexico and Costa Rica, as well as in two individuals from the Yucatan Peninsula in the Atlantic. The number of alleles detected in the Pacific ranged from two to five. All loci amplified in the Yucatan samples and seven loci revealed a unique Atlantic allele. These markers will be useful for studies in the conservation of the species and to study the basic biology of C. erectus.     

Lichen biota of West Siberia

The author has surveyed the diversity of lichen biota of West Siberia and distribution of lichens over its two geographic parts: the West Siberian Plain and the mountain frame in the south of West Siberia. The diversity of lichen biota in entire West Siberia is currently estimated at 1845 species in 325 genera and 95 families. The diversity of the West Siberian Plain is estimated at 1421 species in 271 genera and 86 families, and that of the southern mountains of West Siberia, at 1682 species in 312 genera and 94 families.