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Congenital heart disease (CHD) surges from fetal cardiac dysmorphogenesis and chiefly contributes to perinatal morbidity and cardiovascular disease mortality. A continual rise in prevalence and prerequisite postoperative disease management creates need for better understanding and new strategies to control the disease. The interaction between genetic and non-genetic factors roots the multifactorial status of this disease, which remains incompletely explored. The small non-coding microRNAs (miRs, miRNAs) regulate several biological processes via post-transcriptional regulation of gene expression. Abnormal expression of miRs in developing and adult heart is associated with anomalous cardiac cell differentiation, cardiac dysfunction, and cardiovascular diseases. Here, we attempt to discover the changes in cardiac miRNA transcriptome in CHD patients over those without CHD (non-CHD) and find its role in CHD through functional annotation. This study explores the miRNome in three most commonly occurring CHD subtypes, namely atrial septal defect (ASD), ventricular septal defect (VSD), and tetralogy of fallot (TOF). We found 295 dysregulated miRNAs through high-throughput sequencing of the cardiac tissues. The bioinformatically predicted targets of these differentially expressed miRs were functionally annotated to know they were entailed in cell signal regulatory pathways, profoundly responsible for cell proliferation, survival, angiogenesis, migration and cell cycle regulation. Selective miRs (hsa-miR-221-3p, hsa-miR-218-5p, hsa-miR-873-5p) whose expression was validated by qRT-PCR, have been reported for cardiogenesis, cardiomyocyte proliferation, cardioprotection and cardiac dysfunction. These results indicate that the altered miRNome to be responsible for the disease status in CHD patients. Our data expand the existing knowledge on the epigenetic changes in CHD. In future, characterization of these cardiac-specific miRs will add huge potential to understand cardiac development, function, and molecular pathogenesis of heart diseases with a prospect of epigenetic manipulation for cardiac repair.

Gram-negative intracellular pathogen Vibrio parahaemolyticus manifests its infection through a series of effector proteins released into the host via the type III secretion system. Most of these effector proteins alter signalling pathways of the host to facilitate survival and proliferation of bacteria inside host cells. Here, we report V. parahaemolyticus (serotype O3:K6) infection-induced histone deacetylation in host intestinal epithelial cells, particularly deacetylation of H3K9, H3K56, H3K18 and H4K16 residues. We found a putative NAD+-dependent deacetylase, vp1524 (vpCobB) of V. parahaemolyticus, was overexpressed during infection. Biochemical assays revealed that Vp1524 is a functional NAD+-dependent Sir2 family deacetylase in vitro, which was capable of deacetylating acetylated histones. Furthermore, we observed that vp1524 is expressed and localized to the nuclear periphery of the host cells during infection. Consequently, Vp1524 translocated to nuclear compartments of transfected cells, deacetylated histones, specifically causing deacetylation of those residues (K56, K16, K18) associated with V. parahaemolyticus infection. This infection induced deacetylation resulted in transcriptional repression of several host genes involved in epigenetic regulation, immune response, autophagy etc. Thus, our study shows that a V. parahaemolyticus lysine deacetylase Vp1524 is secreted inside the host cells during infection, modulating host gene expression through histone deacetylation.

In the present study, type 316L(N) bead-on-plates were welded using Activated-Tungsten Inert Gas (A-TIG) welding process with argon and helium gas at various ratios to evaluate the arc characteristics. The welding process parameters including shielding gas composition were optimized using the design of experiments to join 11 mm thick plate in a single pass. In addition, the A-TIG welding technique using optimized process parameters was developed to weld plates up to 20 mm thickness with significantly reduced heat input. High power density of helium arc shielding leads to constricted arc column that enhances arc efficiency and produces deeper penetration.

Several cis-elements including Myb-binding motifs together confer glandular trichome specificity as revealed from heterologous expression and analysis of menthol biosynthesis pathway gene promoters. Glandular Trichomes (GTs) are result of division of epidermal cells that produce diverse metabolites. Species of mint family are important for their essential oil containing many high-value terpenoids, biosynthesized and stored in these GTs. Hence, GTs constitute attractive targets for metabolic engineering and GT-specific promoters are important. In this investigation, the upstream regions of the Mentha × piperita menthol biosynthetic pathway genes (-)-limonene synthase, (-)-P450 limonene-3- hydroxylase, (-)-trans-isopiperitenol dehydrogenase, (-)-Isopiperitenone reductase, ( +)-Pulegone reductase, (-)-Menthone reductase/ (-)-Menthol dehydrogenase and a branched pathway gene ( +)-menthofuran synthase were isolated and characterized. These fragments, fused to β-glucuronidase (GUS) reporter gene of pBI101 binary vector, are able to drive high level gene expression in transgenic tobacco trichomes with strong signals in GTs, except for (-)-Isopiperitenone reductase. The GT-enriched tissue from transformed plants were analysed for GUS enzyme activity and RNA expression which correlates the GUS staining. To characterize the cis-elements responsible for GT-specific expression, a series of 5' deletion constructs for MpPLS and MpPMFS were cloned and analysed in stable transgenic tobacco lines. The specificity of trichome expression was located to - 797 to- 598 bp sequence for (-)-limonene synthase and- 629 to - 530 bp for ( +)-menthofuran synthase promoters containing specific Myb-binding motifs in addition to other unique motifs described for developmental regulation without any defined pattern. All other pathway promoters also recruits specific but different Myb factors as indicated by this analysis.

Hot cracking study on nickel base superalloy, alloy 617M, a candidate material for Advanced Ultra Supercritical (AUSC) power plant applications, was carried out. The susceptibility of this alloy to solidification cracking was evaluated using varestraint (variable restraint) test set up and parameters like Brittleness Temperature Range (BTR) and Critical Strain rate per Temperature drop (CST) were estimated from the results. The BTR and CST for alloy 617M indicate higher susceptibility to solidification cracking than stabilized and un-stabilized austenitic stainless steels. However, mock-up welding of 400 mm diameter alloy 617M hollow forgings with weld thickness of 95 mm and alloy 617M boiler tubes of ~12 wall thickness made from this alloy did not reveal any significant cracking in the welds (except some isolated micro fissures) and hence, a detailed analysis of the results from varestraint tests was taken up. The study revealed the dual hot cracking behaviour of alloy 617M and the reasons behind such observation is elucidated. The microstructural characterisation of the hot crack tested specimens of alloy 617M revealed eutectics of austenite + carbides rich in Mo and Cr in the backfilled regions of the hot cracks in the fusion zone. The formation of significant fraction of eutectic phases along the interdendritic regions at the end of solidification is the primary reason for the high BTR exhibited by alloy 617M. Further, backfilling of the solidification cracks by this eutectic liquid is enabled under low augmented strain and the same is insufficient to aid backfilling in cracks at high restraints. The mechanism mentioned above was found to be the underlying reason for the dual behaviour revealed by alloy 617M. Hence, it was deduced that BTR and CST determined at saturated strain cannot be effectively used to predict the actual hot cracking behaviour of alloy 617M. A refined criterion-BTR at threshold strain is proposed to be an appropriate solidification cracking susceptibility index for this alloy.

Filler-free (FF) welding processes namely, Activated Tungsten Inert Gas welding (ATIG), Laser Beam Welding (LBW), and Friction Stir Welding (FSW) were utilized for joining the nuclear grade 9Cr-1Mo-V-Nb ferritic-martensitic steel and 316 L(N) austenitic stainless steel. A comparative investigation was made by assessing the weld geometries, metallurgical features, material mixing proportions, carbon diffusion behaviour, and mechanical properties of the post-weld heat-treated (PWHT) dissimilar weld joints. Geometries of the weld zones were observed with the transverse and longitudinal macrographs. Metallurgical features were examined by optical microscopy (OM) and Scanning electron microscopy (SEM). Three-phase microstructures were identified in the dissimilar weld zones (DWZ). The elemental distributions were identified by Energy-dispersive X-ray spectroscopy (EDAX). The mixing proportions of the dissimilar alloys and the formation of δ-ferrite in the dissimilar heat-affected zones (HAZ) and DWZ were analytically quantified. Moreover, the diffusion activity of carbides/interstitial carbon atoms was examined by Secondary ion mass spectroscopy (SIMS). In the FSW joints, the intermingled microstructures are recorded with high and stabilized hardness values as compared to the DWZ of the ATIG and LBW joints. In the transverse tensile test, all FF joints were failed at the 316 L(N) base metal (BM) region. Tensile and impact testing of all weld metal indicated that, the weld metal region of the LBW joint exhibited higher strength and lower toughness as compared to the ATIG and FSW joints. The presence of untransformed, recrystallized fine equiaxed austenite along and refined martensitic structure arranged in an alternate layers within the weld metal region of FSW joint caused the higher toughness property than the ATIG and LBW joints.

The enzyme p300, besides having acetyltransferase activity, can also catalyze other acylation modifications, whose physiological implications are still being investigated. Here, we report that the level of histone butyrylation increases globally as well as locally in the promoters of pro-adipogenic genes during adipogenesis. To delineate the role of p300-catalyzed butyrylation from acetylation in adipogenesis, we identified a semisynthetic derivative (LTK-14A) of garcinol, which specifically inhibited histone butyrylation without affecting acetylation. Treatment of 3T3L1 cells with LTK-14A abolished adipogenesis with downregulation of pro-adipogenic genes along with inhibition of H4K5 butyrylation. Administering LTK-14A to high-fat diet-fed and genetically obese db/db mice led to attenuation/decrease in their weight gain. The reduced obesity could be partially attributed to the inhibition of H4K5 butyrylation in adipocytes and liver. This report therefore not only, for the first time, causally links histone butyrylation with adipogenesis but also presents a probable candidate for anti-obesity therapeutics.

Type 316L(N) stainless steel (SS) weld joints were made by employing advanced welding processes such as laser, hybrid laser-MIG (HLM) and hybrid laser-TIG (HLT). First, the welding parameters were identified and full penetration joints were fabricated using 5.6-mm-thick plates. To understand the residual stresses and distortion in weld joints, thermomechanical analysis of advanced welding processes has been performed. The validation of model predictions was carried out experimentally. The hybrid double ellipsoidal heat source coupled with a conical heat source model was used to analyze hybrid welding processes, and the conical model with a cylindrical shell was used for laser welding process. The heat source parameters were fine-tuned by matching the simulated weld profile with the experimentally obtained profile. Thermocouple measurements verified the simulated thermal cycles. Then the predicted temperature distribution was sequentially coupled to the mechanical analysis considering the isotropic hardening model. The simulated residual stresses were confirmed by experimental measurements employing an ultrasonic technique with longitudinally critically refracted (LCR) waves. The hybrid heat source model was found to be accurate for the thermomechanical analysis of the laser and hybrid laser welding of 316L(N) SS. Spot analysis showed that the HAZ of the weld joints exhibited higher residual stresses than the weld metal. The longitudinal tensile residual stress values are lower for the TIG/MIG part than the laser part in the through-thickness direction for the hybrid welds. The weld joint’s measured distortion values are generally low and found to correlate with the weld metal volume.

Creep deformation and rupture behavior of nitrogen-alloyed (0.14 wt.%) nuclear grade 316LN austenitic stainless steel were investigated for the varying stress levels at 873 K and 923 K. The power-law dependency of creep properties such as steady-state creep rate and rupture life on applied stress was observed. For a given applied stress condition, a systematic increase in strain to failure was noticed with increasing temperature from 873 K to 923 K. Irrespective of test temperatures, creep rupture elongation of the steel increased with the increase in rupture lifetime ( $t_{r}$ ) for $t_{r} > 1000$ h. Analysis indicated that the interdependency between creep properties could be well described by the modified Monkman-Grant relationship. The predominance of inter-granular fracture arising from the triple point cracks and/or coalescence of cavities was observed at all the tested conditions for the steel. The enhanced tendency for wedge cracking was noticed for high stress levels at 873 K and 923 K. The evaluated damage tolerance factor $(\lambda ) < 5$ and the calculated ratio between time to reach the Monkman-Grant strain and creep rupture lifetime in the range of 0.69 to 0.80 indicated the accumulation of Monkman-Grant strain for the major fraction of lifetime during creep deformation of 316LN steel.

Summary Background and objective Metabolic disorders including diabetes are associated with immune cell dysfunction. However, the effect of normal glucose metabolism or impairment thereof on immune cell gene expression is not well known. Hence, in this cross-sectional pilot study, we sought to determine the differences in gene expression in the peripheral blood mono-nuclear cells (PBMCs) of normal glucose tolerant (NGT) and prediabetic (PD) Asian Indian men, at fasting and in response to 75 g oral glucose load. Methods Illumina HT12 bead chip-based microarray was performed on PBMCs at fasting and 2-h post load conditions for NGT (N = 6) and PD (N = 9) subjects. Following normalization and due quality control of the raw data, differentially expressed genes (DEGs) under different conditions within and across the two groups were identified using GeneSpring GX V12.0 software. Paired and unpaired Student's t-tests were applied along with fold change cut-offs for appropriate comparisons. Validation of the microarray data was carried out through real-time qPCR analysis. Significantly regulated biological pathways were analyzed by employing DEGs and DAVID resource. Deconvolution of the DEGs between NGT and PD subjects at fasting was performed using CIBERSORT and genes involved in regulatory T-cell (Treg) function were further analyzed for biological significance. Results Glucose load specifically altered the expression of 112 genes in NGT and 356 genes in PD subjects. Biological significance analysis revealed transient up-regulation of innate and adaptive immune response related genes following oral glucose load in NGT individuals, which was not observed in PD subjects. Instead, in the PD group, glucose load led to an increase in the expression of pro-atherogenic and anti-angiogenic genes. Comparison of gene expression at fasting state in PD versus NGT revealed 21,707 differentially expressed genes. Biological significance analysis of the immune function related genes between these two groups (at fasting) revealed higher gene expression of members of the TLR signaling, MHC class II molecules, and T-cell receptor, chemotaxis and adhesion pathways in PD subjects. Expression of interferon-γ (IFN-γ) and TNFα was higher and that of type-1 interferons and TGF-β was lower at fasting state in PD subjects compared to NGT. Additionally, expression of multiple proteasome subunits and protein arginine methyl transferase genes (PRMTs) were higher and that of Treg specific genes was significantly distinct at fasting in PD subjects compared to NGT. Conclusion Prediabetes uncovers constitutive TLR activation, enhanced IFN-γ signaling, and Treg dysfunction at fasting along with altered gene expression response to oral glucose load.

This article makes an attempt to investigate the outcome of activated flux and filler wire in addition to A-TIG welding and TIG welding of Inconel 625 respectively. Ni-Cr-Mo enriched filler namely ERNiCrMo-3 was used to join 6.5-mm-thick plates. Microstructure characterization, mechanical properties evaluation and secondary dendritic arm spacing measurements were carried out to find the cause of the perceived differences. Tensile test failures were observed at the weld zone in both welding processes. Charpy impact studies showed that weldment using A-TIG revealed a low toughness value compared to the TIG weldment. Root bend test showed no discontinuity in both fusion zones and hence, the weldment was produced without defect. The deleterious laves phase was reduced when activated flux and fillers were used. Corrosion performance was undertaken in a 3.5 wt% NaCl solution, to illustrate the outstanding corrosion resistance in Inconel 625’s fusion zone using A-TIG and TIG welding processes.

Dissimilar weldment of 9Cr-1Mo (P9) to 2.25Cr-1Mo (P22) steel processed with fusion welding process must be subjected to post-weld heat treatment (PWHT) prior to operation due to the presence of martensitic microstructure in the weld. However, due to the gradient of carbon activity, PWHT results in the diffusion of carbon from low Cr to high Cr side, which results in a soft zone and hard zone formation in the weld. This would degrade the mechanical properties of the weld joint. In order to tackle this, the present study employed friction stir welding (FSW) process at two different rotational speeds via 200 and 500 rpm. The microstructure and mechanical properties of the FSW specimens were compared with that of activated-gas tungsten arc (A-GTA) weldments. Regardless of the tool speed, the FSW and A-GTA processed specimens indicated martensitic microstructure in the weldment, and hence, PWHT was carried out. The PWHT treated FSW specimen revealed soft and hard zone evolution throughout the weld matrix, whereas in A-GTA welds, no severe diffusional phenomenon was observed across the weld. The A-GTA weld joint exhibited better strength properties than that of the weld joint made by FSW process, and therefore, A-GTA welding can be suitable techniques for welding of P9–P22 steel.

The selection of appropriate heat source model is vital in predicting the temperature distribution and visualizing the dynamic fluid flow behaviour during Laser keyhole welding of Type 316 LN stainless steel. Three-dimensional (3D) numerical models were designed utilizing ANSYS Fluent by employing different heat source models. Different heat source models considered include volumetric heat sources namely Goldak double ellipsoidal, 3D conical, a coalition of 3D conical and cylindrical heat source, 3D volumetric Gaussian and Rotary Gaussian. The simulation was carried out by solving the fundamental conservation equations of mass, momentum and energy. The predicted weld bead profile by different heat sources were compared with the actual weld bead obtained from the laser welding experiment on 0.0055 m thick 316 LN stainless steel (SS) plates. It was found that simulation results of the conical-cylindrical combined (CCC) model exhibited good agreement with actual weld bead dimensions and thermal data obtained during the experiment. Therefore, the conical-cylindrical heat source model is recommended for CFD simulation of full penetration laser welding of 316 LN stainless steel for studying the effect of variation of laser power and surface active element on the weld pool development.

The master epigenetic regulator lysine acetyltransferase (KAT) p300/CBP plays a pivotal role in neuroplasticity and cognitive functions. Recent evidence has shown that in several neurodegenerative diseases, including Alzheimer's disease (AD), the expression level and function of p300/CBP are severely compromised, leading to altered gene expression causing pathological conditions. Here, we show that p300/CBP activation by a small-molecule TTK21, conjugated to carbon nanosphere (CSP) ameliorates Aβ-impaired long-term potentiation (LTP) induced by high-frequency stimulation, theta burst stimulation, and synaptic tagging/capture (STC). This functional rescue was correlated with CSP-TTK21-induced changes in transcription and translation. Mechanistically, we observed that the expression of a large number of synaptic plasticity- and memory-related genes was rescued, presumably by the restoration of p300/CBP mediated acetylation. Collectively, these results suggest that small-molecule activators of p300/CBP could be a potential therapeutic molecule for neurodegenerative diseases like AD.

In metazoan cells, lamins form a proteinaceous meshwork as major structural component of nucleus and also involve in the regulation of essential cellular processes. Lamins along with their interactors act as determinants for chromatin organization throughout the nucleus. Major dominant missense mutations for autosomal dominant forms of muscular dystrophies are resided in the Ig fold domain of lamin A. How lamin A constitutes the distribution of heterochromatin and euchromatin balance, relocates the epigenetic marks in shaping of chromatin states are currently not well defined to make any conclusion about the prognosis of lamin A mediated muscular dystrophies. In the first part of this report, we identified in-vitro organization of full length lamin A proteins due to two well cited Ig LMNA mutations : R453W, W514R by biophysical and electron microscopy observations. We further show both lamin A/C mutant cells were mainly expressed as nucleoplasmic aggregates with reduced amounts at the nuclear envelope.Labelling of specific markers of epigenetics such as H3K9me3,H3K27me3, H3K36me3,Hp1α permitted the correlation of lamin A mutations on epigenetic mechanism. Both immunofluorescence and biochemical analyses are believed to exercise a transcriptional upregulation. Beside the manipulation on epigenetic mechanism, using proteomic studies we trace diverse expressions of transcription regulators, protein components of RNA synthesis and processing, protein translation and posttranslational modification. These data suggests a severe perturbation of targeting of other proteins on nucleus. Our study also portends specific structural configurations of lamin A determined by patterns of it’s interacting partners.

The uptake or expression of hepatitis B virus (HBV) proteins by dendritic cells (DCs) is considered important for disease outcome. Differential expression of microRNA (miRNA) may have a role in viral persistence and hepatocellular injury. The miRNA expression was investigated by microarray in DCs from different stages of HBV infection and liver disease namely, immune active (IA; n = 20); low replicative (LR; n = 20); HBeAg negative (n = 20); acute viral hepatitis (AVH, n = 20) and healthy controls (n = 20). miRNA levels were analyzed by unsupervised hierarchical clustering and principal component analyses and validated by quantitative polymerase Chain Reaction (qPCR). The miRNA-messenger RNA (mRNA)regulatory networks identified 19 miRNAs and 12 target gene interactions in major histocompatibility complex and other immune pathways. miR-2278, miR-615-3p, and miR-3681-3p were downregulated in the IA group compared to healthy control, miR-152-3p and miR-3613-3p in the LR group compared to IA group and miR-152-3p and miR-503-3p in HBe negative compared to LR group. However, miR-7-1-1-3p, miR-192-5p, miR-195-5p, and miR-32-5p in LR, miR-342-3p, and miR-940 in HBe negative, and miR-34a-5p, miR-130b-3p, miR-221-3p, miR-320a, miR-324-5p, and miR-484 in AVH were upregulated. Further, qPCR confirmed changes in miRNA levels and their target genes associated with antigen processing and presentation. Thus, a deregulated network of miRNAs-mRNAs in DCs seems responsible for an impaired immune response during HBV pathogenesis.

This study explored the role of tool rpm in the microstructure evolution and its significant effect on hardness measurement of friction stir welded 2.25Cr–1Mo (P22) steel to AISI 316LN stainless steel. Irrespective of rotational tool speeds, the martensitic phase transformation was found in the P22 steel side of the dissimilar weldments due to the higher peak temperature, and a higher degree of plastic deformation evolved during friction stir welding. Hardness measurements revealed that the average hardness of the martensitic structure that existed in the friction stir weldment of the P22 steel side is 405 ± 5HV0.2. Evolution of martensitic structure with higher hardness emphasizes that the post-weld heat treatment is mandatory for the dissimilar weldment.

Powdery mildew (PM) is a serious fungal disease of legumes. To gain novel insights into PM pathogenesis and host resistance/susceptibility, we used dual RNA-Seq to simultaneously capture host and pathogen transcriptomes at 1 d post-inoculation of resistant and susceptible Medicago truncatula genotypes with the PM Erysiphe pisi (Ep). Differential expression analysis indicates that R-gene mediated resistance against Ep involves extensive transcriptional reprogramming. Functional enrichment of differentially expressed host genes and in silico analysis of co-regulated promoters suggests that amplification of PTI, activation of the JA/ET signaling network, and regulation of growth-defense balance correlate with resistance. In contrast, processes that favor biotrophy, including suppression of defense signaling and programmed cell death, and weaker cell wall defenses are important susceptibility factors. Lastly, Ep effector candidates and genes with known/putative virulence functions were identified, representing a valuable resource that can be leveraged to improve our understanding of legume-PM interactions.

The effect of laser, Hybrid Laser-Tungsten inert gas (HLT) and Hybrid Laser-Metal inert gas (HLM) welding processes on the microstructure and mechanical properties of 5.6 mm thick 316L(N) stainless...

This article presents the welding process parameter optimization for activated tungsten inert gas welding of a 6.5 mm thick Inconel 625 plate. The experimental design L25 has been undertaken to obtain optimal parameters for inputs, including welding current, torch travel speed and arc gap on penetration depth. Welding cross-sectional area, microhardness and welds bead width and bead height have been investigated using various mathematical optimization tools like grey relational analysis (GRA) and Technique for Order Preference by Similarity to Ideal Solution. ANOVA has been used to identify each input parameter’s significance. Through bead on trial experimentation, the computed output results of GRA provided the following recommended settings such as 300 A welding current, 90 mm/min Torch travel speed and 5 mm Arc gap as the best optimized parameters. The optimized samples were examined by a scanning electron microscope with energy dispersive X-Ray spectroscopy techniques for a comprehensive study on the laves phase at the interdendritic regions of the weld zone. X-ray diffraction analysis revealed that the major element present in the weld zone was Ni due to which activated flux quickened the solidification rate and reduced laves phase formation.

This research work emphasis on understanding the weld pool development while carrying out Activated Tungsten Inert Gas (A-TIG) welding by employing Computational Fluid Dynamics (CFD). The influence of temperature coefficient of surface tension (∂γ/∂T) and the concentration of oxygen, the main surface active component on weld bead geometry is studied. A three-dimensional (3D) numerical model has been developed for A-TIG welding process with varying oxygen levels employing ANSYS Fluent for 316LN stainless steel. The general conservation equations consisting mass, energy and momentum were solved in order to acquire the temperature and velocity fields with oxygen levels varying from 50 to 300 ppm in weld pool. The impact of driving forces particularly buoyancy and Marangoni on the weld pool convection were examined. The simulation confirmed that the weld bead shape was influenced mainly by Marangoni convection consecutively dependent on the oxygen content in the weld metal in the course of A-TIG welding. The addition in oxygen content changes the surface tension temperature coefficient ∂γ/∂T from negative to positive gradient causing inward flow. It was found that minor oxygen content in the molten pool until 150 ppm exhibited outward flow and with higher oxygen content beyond 150 ppm exhibited an inward flow. The oxygen content in the weld bead without flux and with flux was found to be 69 and 336 ppm respectively for the type 316LN stainless steel plates welded by A-TIG welding. The simulated weld bead profile was validated by comparing with the experimentally obtained weld bead profile. There was excellent agreement between the two weld bead profiles.

Nuclear lamina is composed of different A-type and B-type lamin proteins and acts as major regulator of DNA replication, transcription, heterochromatin-euchromatin machinery. The majority of mutations in A type lamin are associated with some forms of muscular dystrophies,that majorly distinguishable by a common clinical feature : progressive skeletal muscle wasting. This speculates impaired skeletal muscle differentiation during development and after injury with the influence of myriad of signalling pathways. The molecular mechanism behind phenotypes of lamin A associated muscular dystrophies are still elusive . Here, we used genome wide expression analysis platform during the differentiation of murine C2C12 skeletal muscle cells to investigate the factors have been attributed to the disease. We compared the expression levels of the components of pathways that indicates important role of skeletal muscle as well as identified gene regulatory networks at two different time points of muscle differentiation in wild type and mutant cells. We also report significant perturbations in the expression and activation of Wnt signalling pathway in mutant cells among 40 dysregulated signalling pathways , presenting pronounced regulation of normal downstream myogenic signalling . Finally, with this largest data sets we evaluate in depth characterization of molecular effectors for myogenic differentiation, which could allow greater insight into development of therapeutic strategies for the remission of patients with LMNA linked muscle - related pathologies.

Most of the single point mutations of the LMNA gene are associated with distinct muscular dystrophies, marked by heterogenous phenotypes but primarily the loss and symmetric weakness of skeletal muscle tissue. The molecular mechanism and phenotype-genotype relationships in these muscular dystrophies are poorly understood. An effort has been here to delineating the adaptation of mechanical inputs into biological response by mutant cells of lamin A associated muscular dystrophy. In this study we implement engineered smooth and pattern surfaces of particular young modulus to mimic muscle physiological range. Using fluorescence and atomic force microscopy we present distinct architecture of the actin filament along with abnormally distorted cell and nuclear shape in mutants, which showed a tendency to deviate from wild type cells. Topographic features of pattern surface antagonizes the binding of the cell with it. Correspondingly, from the analysis of genome wide expression data in wild type and mutant cells, we report differential expression of the gene products of the structural components of cell adhesion as well as LINC (linkers of nucleoskeleton and cytoskeleton) protein complexes. This study also reveals mis expressed downstream signaling processes in mutant cells, which could potentially lead to onset of the disease upon the application of engineered materials to substitute the role of conventional cues in instilling cellular behaviors in muscular dystrophies. Collectively, these data support the notion that lamin A is essential for proper cellular mechanotransduction from extracellular environment to the genome and impairment of the muscle cell differentiation in the pathogenic mechanism for lamin A associated muscular dystrophy.

ObjectiveThe master epigenetic enzyme EP300 (p300) besides having lysine acetyltransferase activity can also catalyse other acylation modifications (propionylation, butyrylation, crotonylation etc.), the physiological implications of which are yet to be established fully. We hypothesized that p300 catalysed histone butyrylation may have a causal relationship with adipogenesis and the consequent obesity.MethodsHistone butyrylation pattern was investigated in 3T3L1 cells upon adipogenesis by immunoblotting and chromatin immunoprecipitation experiments. A small molecule modulator that could specifically inhibit p300 catalysed butyrylation without affecting its canonical acetyltransferase activity was screened from a series of compounds and then administered in differentiating 3T3L1 adipocytes as well as high fat diet-induced and genetically obese mice to validate the importance of butyrylation in adipogenesis.ResultsHistone butyrylation was increased upon adipogenesis both globally and locally in the promoters of pro-adipogenic genes along with an upregulation in the expression of acyl CoA generating enzyme Acss2, knockdown of which led to reduced butyrylation. Treatment of differentiating 3T3L1 cells with the p300 specific butyrylation inhibitor LTK-14A led to abrogation of adipogenesis with reduced expression of pro-adipogenic genes and inhibition of H4K5 butyrylation. LTK-14A administration could also attenuate weight gain in both mice models of obesity by preventing adipocyte hypertrophy via H4K5 butyrylation inhibition.ConclusionOur results indicate that p300 catalysed histone butyrylation may have a causal relationship with the process of adipogenesis. Site specific inhibition of butyrylation could lead to adipogenesis repression and hence this epigenetic modification could be targeted for obesity treatment.HighlightsHistone butyrylation has been established as a new epigenetic signature in the context of adipogenesis.To the best of our knowledge, this is the first report of a selective inhibitor of p300 catalysed histone acylation (butyrylation) without affecting its canonical acetyltransferase activity.Specific inhibition of H4K5 butyrylation could be a possible mechanism for inhibiting adipogenesis and hepatic steatosis leading to better control of obesity.LTK-14A class of molecule could be developed as anti-obesity therapeutics.Graphical abstractProposed model for the role of p300-mediated histone butyrylation in adipogenesis:In pre-adipocytes, there exists a basal level of histone acetylation while butyrylation is present to a much lesser extent owing to low stoichiometric levels of butyryl CoA. Induction of adipogenesis causes a simultaneous upregulation of histone acetylation and butyrylation marks leading to increased rate of adipogenesis and concomitant transcriptional activation of pro-adipogeneic genes.Onset of obesity in mice, either due to excess energy intake through high fat diet consumption or increased de novo synthesis of fatty acids due to leptin receptor gene mutation leading to hyperphagic behavior, is accompanied by adipocyte hyperplasia and hypertrophy. Both the organs of adipose tissue and liver were found to have enhanced levels of H4K5 butyrylation during obesity. LTK-14A, a butyrylation specific inhibitor could efficiently prevent the processes of adipogenesis and adipocyte hypertrophy due to inhibition of H4K5 butyrylation in these organs. Thus the compound could attenuate weight gain by selective inhibition of butyrylation without affecting acetylation, thereby highlighting the importance of histone butyrylation in adipogenesis and obesity.

The consequence of friction stir welding (FSW) and activated-gas tungsten arc welding (A-GTAW) processes on the evolution of microstructure and mechanical properties of 9Cr–1Mo (P9) steel to 316LN ...

In the present study, a finite element-based 3D mesh model is used to simulate the effect of welding processes on the temperature distribution, residual stress and distortion in 11-mm-thick 2.25Cr-1Mo steel weld joints. Tungsten inert gas (TIG) and activated-TIG (A-TIG) welding processes were employed for the fabrication of weld joints. Austenite-to-bainite phase transformation is taken into account in the numerical analysis. The heat input fitting tool has been used to calibrate the heat source by matching the simulated weld bead with that of the actual weld bead. Peak temperature was higher at the weld center for A-TIG weld joint, and the weld joint exhibited a sharp temperature gradient at the weld interface. There was good agreement between the predicted and measured thermal cycles. A-TIG and multipass-TIG (MP-TIG) weld joints exhibited similar longitudinal residual stresses in heat affected zone with a difference of 50 MPa. Moreover, A-TIG weld joint fabricated by double-side welding technique employing two passes exhibited reduced distortion than MP-TIG weld joints. A higher magnitude of distortion was in MP-TIG weld joint which was attributed to more weld metal volume caused by more number of weld passes required to fill the V-groove. There was good agreement between the predicted and measured residual stress and distortion values.

Coactivator associated arginine methyltransferase 1 (CARM1) has been functionally implicated in maintenance of pluripotency, cellular differentiation and tumorigenesis; where it plays regulatory roles by virtue of its ability to coactivate transcription as well as to modulate protein function as an arginine methyltransferase. Previous studies establish an oncogenic function of CARM1 in the context of colorectal and breast cancer, which correlate to its overexpressed condition. However, the mechanism behind its deregulated expression in the context of cancer has not been addressed before. In the present study we uncover an oncogenic function of CARM1 in the context of oral cancer, where it was found to be overexpressed. We also identify YY1 to be a positive regulator of CARM1 gene promoter, where silencing of YY1 in oral cancer cell line could lead to reduction in expression of CARM1. In this context, YY1 showed concomitant overexpression in oral cancer patient samples compared to adjacent normal tissue. Cell line based experiments as well as xenograft study revealed pro-neoplastic functions of YY1 in oral cancer. Transcriptomics analysis as well as qRT-PCR validation clearly indicated pro-proliferative, pro-angiogenic and pro-metastatic role of YY1 in oral cancer. We also show that YY1 is a substrate of CARM1 mediated arginine methylation, where the latter could coactivate YY1 mediated reporter gene activation in vivo. Taken together, CARM1 and YY1 were found to regulate each other in a positive feedback loop to facilitate oral cancer progression.

Nuclear grade 316LN austenitic stainless steel weld joints were fabricated using conventional gas tungsten arc welding (GTAW), activated flux gas tungsten arc welding (AGTAW), laser beam welding (LBW) and friction stir welding (FSW) processes. Assessment of weld beads was done by mechanical and metallurgical characterizations. Bead geometry and weld zones were studied by taking macrographs along the transverse side of the weld joints. Metallurgical features of different weld joints were carried out using optical microscopy and scanning electron microscopy. Microhardness distribution across four weld joints was recorded and hardness variations were compared. All weld zone, heat affected zone (HAZ) of GTAW and LBW, thermo-mechanically affected zone (TMAZ) of FSW processes, exhibited higher hardness values than the base metal. Reduced hardness was recorded at HAZ of AGTAW process. This was the result of a considerable grain growth. LBW joint showed the highest hardness value at the center of the fusion zone due to fine equiaxed dendrite morphology. Tensile and impact properties of different welding processes were evaluated and comparisons were made at room temperature. All weld samples displayed high yield strength (YS) and ultimate tensile strength (UTS) with a lower percentage of elongation compared to that of the base metal. FSW joint showed improved YS, UTS and impact toughness compared to other weld joints. This is attributed to the formation of strain-free fine equiaxed grains at stir zone around 5 µm in size with subgrains of 2 µm in size by severe dynamic recrystallization mechanism. Among the fusion welding techniques, AGTAW process exhibited improved toughness, besides almost equal toughness of the base metal due to low δ-Ferrite with high austenite content. Fractography studies of the base metal and different weld samples were carried out by SEM analysis and features were compared.

In this study, friction stir welding (FSW) of 9Cr-1Mo steel was carried out with tungsten lanthanum oxide (W-La2O3) tool to study the influence of tool rotation speeds (200 rpm and 500 rpm) on microstructure and hardness. A smooth defect-free weld joint with complete penetration was accomplished by both rotational speeds. In stir zone (SZ), a fine and lath martensitic microstructure was explored for the 200 rpm and the 500 rpm welds, respectively. The tangible increment in the average hardness of both SZ and thermomechanical affected zone (TMAZ) compared to the base metal (stir zone/TMAZ: ~ 420 VHN, base metal: ~ 212 VHN) was observed due to the effect of phase transformation.

In this work, activated TIG (A-TIG) welding on 8 mm thick plates of AISI 316L stainless steel was carried out. The effect of various single component fluxes and a multi-component flux on weld bead geometries was analysed. The multi-component flux mixture resulted in though thickness penetration in a single pass. Metallography of different zones was observed and weld zone was found to exhibit austenitic-ferritic microstructure. Delta ferrite content was measured with Ferritoscope and increase in delta ferrite content was observed in A-TIG weld zones as compared to base metal. From microhardness measurements, weld zone was found to be harder than the base metal due to increase in delta ferrite fraction.