Paired box genes, PAX-2 and PAX-8, are not frequently mutated in Wilms tumor

To determine whether PAX-2 and PAX-8 are involved in Wilms tumor (WT) pathogenesis, we sought mutations in these two genes in 99 Wilms tumors of favorable histology. We screened the entire protein coding sequences as well as the intronic regions adjacent to exons, using denaturing HPLC followed by sequencing of samples displaying abnormal chromatograms. In PAX-2, a silent polymorphism was found within exon 2 and exon 8 in 1% and 21% of cases, respectively. Three apparently silent polymorphisms were also found in PAX-8, two in exon 5 (2 of 99 cases or 2%) and one in exon 6 (22 of 99 cases or 22%), all of which were located 3' to the exons. In conclusion, no evidence for disease causing mutation was found using this technique, and so the direct involvement of either of these two genes in WT is unlikely.     

Association analysis between four vitamin D receptor gene polymorphisms and developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is a congenital condition characterized by abnormality in acetabulum size and/or shape. The incidence rate of DDH differs between different populations with risk factors including positive family history, breech presentation, sex, firstborn status, side of the hip, mode of delivery and oligohydramnios. It is recognized that DDH has a genetic component that exhibit autosomal dominant patterns. Many candidate genes have been studied and found to be associated with the disease; most of them are normally involved in cartilage development and joint metabolism. In this study, the association of four single-nucleotide polymorphisms (SNPs) (rs731236, rs1544410, rs7975232 and rs2228570) in the vitamin D receptor (VDR) gene was studied by a case–control analysis. The study sample involves 50 cases with confirmed DDH presentation and 50 nonDDH controls. SNPs were genotyped using conventional polymerase chain reaction (PCR) and restriction fragment-length polymorphism (RFLP) techniques. Genotype and allele frequencies were analysed using SPSS software. No significant associations were found between the VDR polymorphisms analysed and DDH. Further work need to be performed using genomewide analysis to elucidate the genetic basis of DDH.     

Photocatalytic degradation of pesticide methomyl: determination of the reaction pathway and identification of intermediate products.

The degradation of pesticide methomyl in aqueous solution by UV-irradiation in the presence of TiO2 "Degussa P-25" has been studied. It was found that mineralisation to carbon dioxide, water, sulfate and ammonia took place during the process. The rate of photodecomposition of methomyl was measured using high performance liquid chromatography (HPLC), while its mineralization was followed using ion chromatography (IC), and total organic carbon (TOC) analysis. The identification of reaction intermediate products was carried out using coupled techniques HPLC-MS (electrospray ionization in positive mode) and a degradation pathway was proposed. Under our conditions, complete disappearance of 1.23 x 10(-4) mol l(-1) of pure pesticide occurred within 45 min of illumination and 80% TOC removal occurred in less than 4 h. Three main intermediates were identified resulting from (i) the rupture of the ester bond (or the N-O bond), (ii) the hydroxylation of methyl group borne by the nitrogen atom and (iii) the product resulting from the decarboxylation of the oxidized hydroxylated methyl group (photo-Kolbe reaction). In order to be sure that the photocatalytic results were consistent, hydrolysis and photolysis tests were performed. Photocatalysis proved to be an excellent new advanced oxidation technology (AOT) to eliminate methomyl present in water.     

Connective tissue growth factor (CTGF) acts as a downstream mediator of TGF-beta1 to induce mesenchymal cell condensation

Mesenchymal cell (MC) condensation or the aggregation of MCs precedes chondrocyte differentiation and is required for subsequent cartilage formation during endochondral ossification. In this study, we used micromass cultures of C3H10T1/2 cells as an in vitro model system for studying MC condensation and the events important for this process. Transforming growth factor beta1 (TGF-beta1) served as the initiator of MC condensation in our model system and we were interested in determining whether CTGF functions as a downstream mediator of TGF-beta1. CTGF is a matricellular protein that has been found to be expressed in MC condensations and in the perichondrium. Micromass cultures of C3H10T1/2 cells condensed under TGF-beta1 stimulation concomitant with dramatic up-regulation of CTGF mRNA and protein levels. CTGF silencing by either CTGF siRNA or CTGF antisense oligonucleotide approaches showed that TGF-beta1-induced condensation was CTGF dependent. Furthermore, silencing of CTGF expression resulted in significant reductions in cell proliferation and migration, events that are crucial during MC condensation. In addition, up-regulation of Fibronectin (FN) and suppression of Sox9 expression by TGF-beta1 was also found to be mediated by CTGF. Immunofluorescence of developing mouse vertebrae showed that CTGF, TGF-beta1 and FN were co-expressed in condensations of MCs, while Sox9 expression was low at this stage. During subsequent chondrogenesis, Sox9 expression was high in chondrocytes while CTGF expression was limited to the perichondrium. Thus, CTGF is an essential downstream mediator of TGF-beta1-induced MC condensation through its effects on cell proliferation and migration. CTGF is also involved in up-regulating FN and suppressing Sox9 expression during TGF-beta1 induced MC condensation.     

Spectrofluorimetric analysis of gemifloxacin mesylate in pharmaceutical formulations

A simple, rapid and highly sensitive spectrofluorimetric method was developed for determination of gemifloxacin mesylate (GFX) in tablets. The method is based on measuring the native fluorescence of GFX in isopropanol at 400 nm after excitation at 272 nm. The fluorescence–concentration plot was rectilinear over the range of 0.01–0.50 µg/mL with a lower detection limit of 1.19 ng/mL and quantification limit of 3.6 ng/mL. The method was fully validated and successfully applied to the determination of GFX tablets with an average percentage recovery of 99.65 ± 0.532. The method was extended to the stability study of GFX. The drug was exposed to acidic, alkaline, oxidative and photolytic degradation according to International Conference on Harmonization guidelines. The rate of GFX degradation was found at its highest in acidic conditions, and in its lowest in the neutral one. However, it was stable under dry heat and photolytic degradation conditions. Copyright © 2013 John Wiley & Sons, Ltd.     

Uridine and the Control of Phototropism in Oat (Avena sativa L.) Coleoptiles

The short-term growth response of oat (Avena sativa L.) coleoptiles to exogenously applied uridine was studied both in excised apical segments and in the intact seedlings. In both cases growth of coleoptile tissue was inhibited by uridine. The inhibition of coleoptile growth consistently occurred 20–30 min after uridine treatment, which is within the lag period of their phototropic response. Asymmetric application of uridine to coleoptiles in the intact seedlings resulted in their bending toward the direction to which uridine was applied in the absence of light stimulus. These findings suggest that uridine or its metabolites, plays an important role in the phototropism of oat coleoptiles and provide support to the Bruinsma–Hasegawa theory as an alternative to the Cholodny–Went theory for explaining phototropism.     

Effects of ethylene and inhibitors of ethylene synthesis and action on nodulation in common bean (Phaseolus vulgaris L.)

The ethylene releasing compound, 2-chloroethylphosphonic acid (ethephon) inhibited nodule development in common bean (Phaseolus vulgaris L.) plants. In contrast, inhibitors of ethylene synthesis or its physiological activity enhanced nodulation. In a co-culture of bean seeds and rhizobia, ethephon inhibited rhizobial growth while inhibitors of ethylene synthesis or action did not influence the growth and proliferation of rhizobia. These data emphasize the role of ethylene as a regulator of nodulation in determinate nodulators and indicate that the ethylene signaling pathway involved in the nodulation process is not limited to the plant host but also involves the bacterial symbiont.     

Mass spectrometric profiling of oxidized lipid products in human nonalcoholic fatty liver disease and nonalcoholic steatohepatitis

Oxidative stress is a core abnormality responsible for disease progression in nonalcoholic fatty liver disease (NAFLD). However, the pathways that contribute to oxidative damage in vivo are poorly understood. Our aims were to define the circulating profile of lipid oxidation products in NAFLD patients, the source of these products, and assess whether their circulating levels reflect histological changes in the liver. The levels of multiple structurally specific oxidized fatty acids, including individual hydroxy-eicosatetraenoic acids (HETE), hydroxy-octadecadenoic acids (HODE), and oxo-octadecadenoic acids (oxoODE), were measured by mass spectrometry in plasma at time of liver biopsy in an initial cohort of 73 and a validation cohort of 49 consecutive patients. Of the markers monitored, 9- and 13-HODEs and 9- and 13-oxoODEs, products of free radical-mediated oxidation of linoleic acid (LA), were significantly elevated in patients with nonalcoholic steatohepatitis (NASH), compared with patients with steatosis. A strong correlation was revealed between these oxidation products and liver histopathology (inflammation, fibrosis, and steatosis). Further analyses of HODEs showed equivalent R and S chiral distribution. A risk score for NASH (oxNASH) was developed in the initial clinical cohort and shown to have high diagnostic accuracy for NASH versus steatosis in the independent validation cohort. Subjects with elevated oxNASH levels (top tertile) were 9.7-fold (P < 0.0001) more likely to have NASH than those with low levels (bottom tertile). Collectively, these findings support a key role for free radical-mediated linoleic acid oxidation in human NASH and define a risk score, oxNASH, for noninvasive detection of the presence of NASH.