Study the Physical Properties of Some Alloy Materials and Effect of Gamma Radiation

The present paper reports the effect of replacement of selenium by tellurium on the optical gap and some other physical parameters of new quaternary chalcogenide TexGe20Se(60-x)As20 (x = 0, 10, 15 and 20 at. %) thin films. Thin films with thickness 100 nm of TexGe20Se(60-x)As20 were prepared by thermal evaporation of the bulk samples. Increasing tellurium content is found to affect the average heat of atomization, cohesive energy and energy gap of the TexGe20Se(60-x)As20 alloys. Optical absorption measurements showed that the fundamental absorption edge is a function of composition. The optical absorption is due to allowed direct transition and the energy gap decreases with the increase of tellurium content. The chemical bond approach has been applied successfully to interpret the decrease of the optical gap with increasing tellurium content. it has also been observed that the increase of Te was followed by decrease in glass transition temperature. The prepared films were irradiated by gamma rays at doses up to 200kGy. It was found that the compositions were almost stable against gamma radiation. Keywords: amorphous, chalcogenide, optical properties

Identification of the splice variants of Recepteur d'Origine nantais (RON) in lung cancer cell lines

RON receptor tyrosine kinase is a transmembrane protein directly involved in suppression of inflammation and its aberrant expression linked to cancers and metastasis. Efforts to block deregulated RON signaling in tumors using small molecule kinase inhibitors or antibodies have been complicated by the presence of unknown number/types of isoforms of RON, which, despite being structurally similar, localize differently and mediate varied functions. Current study was designed to identify the splice variants of RON transcripts formed by skipping of sequences between exons 9 and 14 for better understanding of isoform specific RON signaling in cancers. PCR amplification and bi-directional sequencing of a 901 bp cDNA sequence located between exons 9 to 14 of RON from lung cancer cell lines revealed the presence of two splicing variants formed by skipping of exons 11 and 11–13. Each of these transcripts was found in more than one cell line. Expressed sequence tag (EST) database search indicated that the splicing variant lacking exons 11–13 was a novel one. Here we conclude that the splice variants of RON lacking exon 11 and exons 11–13 were detected in several lung cancer cell lines. Novel variant formed by skipping exons 11–13, the sequence of which code for transmembrane region, is predicted to code for a truncated isoform that may be secreted out. Tumors may antagonize the ligand dependent anti-inflammatory function of wild-type RON by secreting out the ligand binding isoforms

1,2,4-Trimethylbenzene Transformation Reaction Compared With Its Transalkylation Reaction With Toluene Over USY Zeolite

1,2,4-Trimethylbenzene (TMB) transalkylation with toluene has been studied over USY zeolite type catalyst using a riser simulator that mimics the operation of a fluidized-bed reactor. Reaction mixtures of 50:50 wt % TMB and toluene were used for the transalkylation reaction. The range of temperature investigated was 400-500 degrees C with time on stream ranging from 3 to 15 s. The effect of reaction conditions on the variation of the p-xylene to o-xylene product ratio (P/O), distribution of trimethylbenzene (TMB) isomers (1,3,5-TMB to 1,2,3-TMB), and values of xylene/tetramethylbenzene (X/TeMB) ratios are reported. Comparisons are made between the results of the transalkylation reaction with the results of pure 1,2,4- TMB and toluene reactions earlier reported. Toluene, which was found almost inactive, became reactive upon blending with 1,2,4-TMB. This shows that toluene would rather accept a methyl group to transform to xylene than lose a methyl group to form benzene under the present experimental conditions. The experimental results were modeled using a quasi-steady-state approximation. Kinetic parameters for the 1,2,4-TMB disappearance during the transalkylation reaction and in its conversion into isomerization and disproportionation products were calculated using the catalyst activity decay function based on time on stream (TOS). The apparent activation energies were found to decrease as follows: E-transalkylation > E-isomerization > E-disproportionation

Catalytic Transformation Of C-7-C9 Methyl Benzenes Over USY-Based FCC Zeolite Catalyst

Catalytic transformation of three methyl benzenes (toluene, m-xylene, and 1,2,4- trimethylbenzene) has been investigated over USY-based FCC zeolite catalyst in a novel Riser Simulator at different operating conditions. The effect of reaction conditions on the variation of isomerization to disproportionation products ratio (I/D), distribution of trimethylbenzene (TMB) isomers (1,3,5-to-1,2,3-) and values of pxylene/ o-xylene (P/O) ratios are reported. The sequence of reactivity of the three alkyl benzenes was found to decrease as the number of methyl group per benzene ring decreases, as follows: 1,2,4-trimethylbenzene > m-xylene > toluene. This is true at all temperatures investigated over the USY zeolite. Toluene was found unreactive in our reaction condition. Effectiveness factor (eta(ss)) of both 1,2,4-TMB and m-xylene have been estimated. While m-xylene's eta(ss) was close to unity at all condition, 1,2,4-TMB's eta(ss) was less than that of m-xylene. The effectiveness factor was estimated from the quasi-steady state approximation modeling of the experimental data involving a decay function based on 'Time on Stream' (TOS). Based on the present study, it was found that the number of methyl groups has the most important role on the reactivity of 1,2,4-TMB, m-xylene and toluene over Y-based catalyst

Favorable Changes in Fasting Glucose in a 6-month Self-Monitored Lifestyle Modification Programme Inversely Affects Spexin Levels in Females with Prediabetes

Spexin (SPX) is a novel peptide thought to have a role in various metabolic regulations. Given its presumed body-weight regulatory functions, we aimed to determine whether lifestyle intervention programs on weight loss and fasting glucose (FG) improvement among people with impaired glucose regulation also alter levels of circulating SPX. A total of 160 Saudi adult males and females with prediabetes were randomly selected from a larger cohort (N = 294) who underwent a 6-month lifestyle modification program to improve their glycemic status. Participants were split into two groups based on differences in glucose levels post-intervention, with the first 50% (improved group) having the most significant reduction in FG. SPX was measured at baseline and after 6 months. Changes in SPX was significant only in the improved group [baseline: median (Q1\u2013Q3) of 164 pg/ml (136\u2013227) vs follow-up: 176 pg/ml (146\u2013285); p < 0.01]. When stratified by sex, the significant increase was observed only in females [159 pg/ml (127\u2013252) vs 182.5 (152,369.1); p < 0.01]. Furthermore, SPX levels showed a significant inverse association with FG (\u3b2 = 120.22, p = 0.003) even after adjustment with age and BMI, again only in females. Circulating SPX levels increase over time in people with prediabetes, particularly women who responded favorably in a 6-month lifestyle intervention program. Whether an unknown mechanism regulating the sexual disparity seen in SPX levels post-intervention exists should be further investigated using a larger sample size

SNPs in FNDC5 (irisin) are associated with obesity and modulation of glucose and lipid metabolism in Saudi subjects

Background: Irisin is a recently identified myokine that plays an important role in preventing obesity and insulin resistance. We investigated whether the common FNDC5 (irisin precursor) gene variants influence susceptibility to obesity and type 2 diabetes (T2D) and verified the impact of FNDC5 gene variants on serum irisin levels, glucose and lipid metabolism in a Saudi population. Methods: Genomic DNA from 814 (394 T2DM and 414 controls) subjects were genotyped for the five common SNPs (rs3480A/G, rs1746661G/T, rs1298190A/G, rs726344A/G and rs1570569G/T) of the FNDC5 gene using the TaqMan genotyping assay. Biochemical parameters and hematic concentrations of irisin and insulin as well as anthropometric indices were collected. Results: Serum irisin levels were higher in T2DM patients compared to controls (p < 0.0001). Analyses of FNDC5 SNPs showed that: 1) The rs3480 GG associates with decreased risk of obesity (p = 0.005; odds ratio: 0.48) and lower body mass index (BMI) values (p = 0.03). In addition, GGAAG was identified as the protective haplotype against risk of obesity (p = 0.001; odds ratio: 0.23). 2) The rs1746661 G allele associates with higher triglyceride (TG) levels (p = 0.019). 3) The rs157069 TT genotype associates with higher fasting insulin (p = 0.029) and HOMA-IR (p = 0.002) as well as with lower circulating irisin levels (p = 0.016). Conclusions: SNPs in FNDC5 gene correlates with obesity and glucose-lipid metabolism possibly because they modulate the serum levels of irisin

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele