556 research outputs found
Utilization of iron values of red mud for metallurgical applications
A brief overview on the utilization of iron values of red mud is presented along with the results of some recent investigations conducted at National Metallurgical Laboratory. Red mud from Nalco, characterized by high iron content, is used in the studies. Two different strategies are explored : (a) extraction of iron and other metal values from red mud using a pat-ented process, named as Elgai process, available for the removal of alumina from iron ores; and (b) use of red mud as an additive in the iron ore sintering. The second approach has particularly yielded interesting results. Sinter with acceptable physical properties and reducibility could be produced with red mud addition from 50 to 125 kg/tonne of sinter. Red mud addition leads to the dilution of the iron content of sinter. It is suggested that this problem can be circumvented with addition of blue dust, a waste material, along with red mud
Measures of egg quality and hatchery performance of Arctic charr (Salvelinus alpinus L.) and Atlantic salmon (Salmo salar L.)
The present study examined how morphological, biological and biochemical characteristics of eggs correlated with overall performance (survival, growth) of eggs and alevins of Arctic charr (Salvelinus alpinus) and Atlantic salmon (Salmo salar). In addition, the effect of time of stripping on biochemical composition of laboratory-reared charr eggs was studied, and the biological, morphological and biochemical egg quality criteria of cultured and wild Atlantic salmon (anadromous) were compared and evaluated. Fertilization and hatching success, growth and survival of developing embryos, alevins and fry were recorded as biological measures of egg quality. These measures were compared to levels of protein, lipid, carbohydrate, moisture, ash, total and free amino acids as potential biochemical indicators, and to egg size, yolk-sac volume at hatching, alevin size at hatching and age at hatching as potential morphological indicators of egg quality. -- For Arctic charr, eggs collected in the middle of the spawning period had the highest protein, lipid, carbohydrate and energy content, which were associated with higher fertilization and hatching success, and growth and survival of embryos, alevins and fry, than that of eggs collected early or late in the spawning period. Eggs collected from wild Atlantic salmon had higher protein, lipid, carbohydrate and energy content and concomitantly higher fertilization and hatching success, faster development and greater growth and survival of embryos, alevins and fry than those collected from cultured stock. The total amino acid pool, and the protein, lipid, carbohydrate and energy content of eggs, alevins and fry decreased simultaneously during embryonic development of both Arctic charr and Atlantic salmon because they were utilized in metabolic processes. -- Egg diameter and alevin length were positively correlated with egg weight and alevin weight, respectively. There was no correlation between egg weight and alevin weight or egg diameter and alevin length at hatching for either Arctic charr or Atlantic salmon. -- The amino acids, serine, valine, tryptophan, lysine, isoleucine and threonine were important for growth and survival of embryos, alevins and fry of Arctic charr. However, alanine, aspartic acid, histidine, isoleucine, leucine, lysine, phenylalanine, proline, serine, threonine, tyrosine and valine were important for growth and survival of embryos, alevins and fry of Atlantic salmon. -- It is suggested that energy level and/or amino acid content of eggs could be used as a condition index for the future development, growth and survival of embryos and alevins of salmonids
Rottlerin-induced autophagy leads to the apoptosis in breast cancer stem cells: molecular mechanisms
Abstract
Background
Autophagy is an indispensable lysosomal self-digestion process involved in the degradation of aggregated proteins and damaged organelles. Autophagy is associated with the several pathological processes, including cancer. Cancer stem cells (CSCs) play significant roles in cancer initiation, progression and drug resistance. Recent studies have demonstrated the antitumor activities of plant-derived chemopreventive agent rottlerin (Rott). However, the molecular mechanism by which Rott induces autophagy in breast CSCs has not been investigated.
Results
The objectives of this study were to examine the molecular mechanism by which Rott induces autophagy which leads to apoptosis in breast CSCs. Treatment of breast CSCs with Rott for 24 h resulted in a concentration dependent induction of autophagy, followed by apoptosis as measured by flow cytometry. Electron microscopy confirmed the presence of autophagosomes in Rott treated breast CSCs. Western blot analysis showed that Rott treatment increased the expression of LC3, Beclin-1 and Atg12 that are accumulated during autophagy. Prolonged exposure of breast CSCs to Rott caused apoptosis which was associated with the suppression of phosphorylated Akt and mTOR, upregulation of phosphorylated AMPK, and downregulation of anti-apoptosis Bcl-2, Bcl-XL, XIAP and cIAP-1. Knock-down of Atg7 or Beclin-1 by shRNA inhibited Rott-induced autophagy at 24 h. Our study also demonstrates that pre-treatment of breast CSCs with autophagosome inhibitors 3-methyladenine and Bafilomycin, as well as protein synthesis inhibitor cycloheximide inhibited Rott-induced autophagy and apoptosis. Rott induces autophagy via extensive cytoplasmic vacuolization in breast CSCs. Molecular docking results between C2-domain of protein kinase C-delta and Rott indicated that both hydrogen bonding and hydrophobic interactions contributed significantly for ligand binding with minimum binding affinity of ≈ 7.5 Kcal/mol. Although, autophagy inhibitors suppress the formation of cytoplasmic vacuolization and autophagy in breast CSCs, the potency of Rott to induce autophagy and apoptosis might be based on its capability to activate several pathways such as AMPK and proteasome inhibition.
Conclusions
A better understanding of the relationship between autophagy and apoptosis would eventually allow us to discover novel drugs for the treatment of breast cancer by eliminating CSCs.Peer Reviewe
Practical stability and boundedness criteria of impulsive differential system with initial time difference
In this paper, an impulsive differential system is investigated for the first time for practical stability and boundedness criteria with respect to initial time difference. The investigations are carried out by perturbing Lyapunov functions and by using comparison results. A generalized Lyapunov function has been used for the investigation. The present results indicate that the stability criteria significantly depend on the moment of impulses.Publisher's Versio
Surface modification and parametric optimization of tensile strength of Al6082/SiC/waste material surface composite produced by friction stir processing
Friction stir processing (FSP) is one of the promising tools to enhance the mechanical and microstructural features of any engineering material due to its excellence in grain refinement. Further, the successful utilization of waste material into a useful product instigates the use of chicken bone powder (CBP), walnut shell powder (WSP), and rice husk powder (RHP) as secondary reinforcement to develop surface composites and metal matrix composites to enhance the mechanical properties. In the present work, a surface composite of base alloy Al6082 is developed through the utilization of SiC as primary reinforcement and CBP, WSP, and RHP as secondary reinforcement. The experiments were performed as per Taguchi's L9 orthogonal array and the analysis of variance (ANOVA) response is discussed in detail. The process parameters taken for the study are the type of tool pin profile such as hexagonal, square, and cylindrical threaded along with rotational speed and tool tilt angle. The result revealed the microstructural characterization through field emission scanning electron microscopy (FESEM) images equipped with energy-dispersive X-ray spectroscopy (EDS) phase mapping and elemental spectrum. The tensile strength of each specimen was tested through a horizontal tensometer and further studied to get the optimized value of the process parameter to achieve a larger value. The use of a hexagonal pin profile with the optimized value of the rotational speed of 1500 rpm and 3 degrees tilt angle gives the higher tensile strength of 250.64 MPa.Web of Science1212art. no. 190
Microbial beta glucosidase enzymes: recent advances in biomass conversation for biofuels application
The biomass to biofuels production process is green, sustainable, and an advanced technique to resolve the current environmental issues generated from fossil fuels. The production of biofuels from biomass is an enzyme mediated process, wherein β-glucosidase (BGL) enzymes play a key role in biomass hydrolysis by producing monomeric sugars from cellulose-based oligosaccharides. However, the production and availability of these enzymes realize their major role to increase the overall production cost of biomass to biofuels production technology. Therefore, the present review is focused on evaluating the production and efficiency of β-glucosidase enzymes in the bioconversion of cellulosic biomass for biofuel production at an industrial scale, providing its mechanism and classification. The application of BGL enzymes in the biomass conversion process has been discussed along with the recent developments and existing issues. Moreover, the production and development of microbial BGL enzymes have been explained in detail, along with the recent advancements made in the field. Finally, current hurdles and future suggestions have been provided for the future developments. This review is likely to set a benchmark in the area of cost effective BGL enzyme production, specifically in the biorefinery area
Transdural herniated lumbar disc disease with muscle patch for closure of durotomy – A Brief review of literature
Purpose
Intradural migration of disc (IDMD) is a rare clinical entity accounting for 0.27–0.33% of all herniated disc diseases. Flimsy or dense adhesion between the ventral dural surface and the opposing posterior longitudinal ligament (PLL) is the principal pathology for intradural migrated disc. The most commonly affected lumbar segments are L4-5 (55%), L3-4 (16%), L5-S1 (10%) and less commonly L2L3 and L1L2. No imaging feature is characteristic and the management protocol of durotomy via an endoscopic method is unclear.
Methods
An L5S1 disc disease was operated by endoscopic method. Difficulty in separating the dural sac from PLL, dense adhesions prompting sharp dissection at this location and a calcified disc are the earliest evidence of intradural migration. MRI features of an intradural location are loss of continuity of posterior longitudinal ligament, beak-like appearance also known as “Hawk-beak sign”, peripheral enhancement around an intradural disc, fluid-filled intradural cyst. Magnification either by Microscope or Endoscope is of importance when dissecting the intradural disc so as to avoid the nerve root injury. Liberal use of fibrin glue and augmentation with muscle patch was performed.
Results
Ambulated by 48h and discharged by 5th day. Two and 9 months follow up showed no evidence of pseudomeningocoele.
Conclusion
Autologous muscle patch with fibrin glue for dural rent closure is a simple and effective method which can be performed by endoscopic or minimally invasive approaches. Suturing the dura, being a tedious and cumbersome procedure can be avoided
Mapping QTLs Controlling Flowering Time, Plant Height, Panicle length and Grain Mass in Pearl Millet [Pennisetum glaucum (L.) R. Br.]
Pearl millet is an important cereal of arid- and semi-arid regions, and can endure dry conditions but experiences drought stress during post-flowering growth. Exploiting the bold seeded semi-dwarf early flowering genotypes in pearl millet is a key breeding strategy to enhance yield and for adequate food in resource-poor zones. Genetic variation for agronomic traits of pearl millet inbreds can be used to dissect complex traits through QTL mapping. Quantitative trait locus (QTL) mapping for 50% flowering time, plant height, panicle length, and grain mass (self and open pollinated seeds) was performed in recombinant inbred line (RIL) population, ICMB 841-P3 ? 863B-P2. Correlations between traits were also performed and significantly negative association between plant height and TGM was observed. High heritabilities (>0.6) were recorded for all traits. A total of 50 QTLs that affected above traits were detected. Six putative QTLs for 50% flowering time were identified on five chromosomes. One QTL on LG3 were common between flowering time and plant height. Three major QTLs for panicle length, one each on LG1, LG2 and LG6B were detected.The major QTL for TGM_self on LG 6B had a partial R2 of 23.8% and 0.8 additive effects.The total phenotypic variance for 50% FT, TGM_self, and panicle length was 23.2% (LOD- 56.28), 22.3% (LOD- 5.96) and 59.4% (LOD- 52), respectively.A total of 21 digenic interactions were demonstrated for 50%FT (R2=18%-40%) and PL (R2publishersversionPeer reviewe
Differential Expression of Heat Shock Protein (HSP) 70-2 Gene Polymorphism in Benign and Malignant Pancreatic Disorders and Its Relationship with Disease Severity and Complications
Context The role of heat shock protein (HSP) 70-2 gene polymorphism (at position 1267, A to G transition) in patients with pancreatic disorders is not clear. Objective To evaluate HSP 70-2 gene polymorphism (at position 1267, A to G transition) in patients with acute and chronic pancreatitis as well as pancreatic carcinoma, and to find any association of this polymorphism with disease complications and severity. Methods One-hundred and fifty patients (50 each of acute, chronic pancreatitis, and pancreatic carcinoma) and 50 healthy blood donors as controls were prospectively studied. Three alleles (AA, AG and GG) of HSP 70-2 gene determined by PstI restriction fragment length polymorphism. Results There was a statistically significant difference in the distribution pattern of HSP 70-2 gene polymorphism in patients with acute pancreatitis (P=0.001) and pancreatic carcinoma (P<0.001) as compared to controls. The frequency of mutant allele (G allele) was significantly higher in diseased group as compared to control group (19% in control group, 40% in acute pancreatitis, 33% in chronic pancreatitis and 45% in pancreatic carcinoma). No association of this polymorphism was found with disease severity in patients with acute and chronic pancreatitis or pancreatic carcinoma. Conclusions In our patient sample the frequency of mutant allele (G allele) of HSP 70-2 gene is significantly higher in patients with acute pancreatitis and pancreatic carcinoma compared to controls (50 healthy blood donors). However, this polymorphism was not associated with disease severity and complications.Image: Allelic distribution in the study population
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