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51.
Selvaraj Jayaraman Nalini Devarajan Ponnulakshmi Rajagopal Shyamaladevi Babu Senthil Kumar Ganesan Vishnu Priya Veeraraghavan Chella Perumal Palanisamy Bo Cui Vijayalakshmi Periyasamy Kirubhanand Chandrasekar 《Molecules (Basel, Switzerland)》2021,26(7)
β-sitosterol (SIT), the most abundant bioactive component of vegetable oil and other plants, is a highly potent antidiabetic drug. Our previous studies show that SIT controls hyperglycemia and insulin resistance by activating insulin receptor and glucose transporter 4 (GLUT-4) in the adipocytes of obesity induced type 2 diabetic rats. The current research was undertaken to investigate if SIT could also exert its antidiabetic effects by circumventing adipocyte induced inflammation, a key driving factor for insulin resistance in obese individuals. Effective dose of SIT (20 mg/kg b.wt) was administered orally for 30 days to high fat diet and sucrose induced type-2 diabetic rats. Metformin, the conventionally used antidiabetic drug was used as a positive control. Interestingly, SIT treatment restores the elevated serum levels of proinflammatory cytokines including leptin, resistin, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) to normalcy and increases anti-inflammatory adipocytokines including adiponectin in type 2 diabetic rats. Furthermore, SIT decreases sterol regulatory element binding protein-1c (SREBP-1c) and enhances Peroxisome Proliferator–activated receptor-γ (PPAR-γ) gene expression in adipocytes of diabetic rats. The gene and protein expression of c-Jun-N-terminal kinase-1 (JNK1), inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ) and nuclear factor kappa B (NF-κB) were also significantly attenuated in SIT treated groups. More importantly, SIT acts very effectively as metformin to circumvent inflammation and insulin resistance in diabetic rats. Our results clearly show that SIT inhibits obesity induced insulin resistance by ameliorating the inflammatory events in the adipose tissue through the downregulation of IKKβ/NF-κB and c-Jun-N-terminal kinase (JNK) signaling pathway. 相似文献
52.
Lin N Langner A Tait SL Rajadurai C Ruben M Kern K 《Chemical communications (Cambridge, England)》2007,(46):4860-4862
Scanning tunneling microscopy reveals, at single-molecular resolution, how external parameters--substrate morphology and guest addition--re-direct the assembly of dumbbell-shaped coordination supramolecules towards different surface-confined supramolecular organizations. 相似文献
53.
An experimental investigation on the convective heat transfer and friction factor characteristics in the plain and dimpled
tube under laminar flow with constant heat flux is carried out with distilled water and CuO/water nanofluids. For this, CuO
nanoparticles with an average size of 15.3 nm were synthesized by sol–gel method. The nanoparticles are then dispersed in
distilled water to form stable suspension of CuO/water nanofluid containing 0.1, 0.2 and 0.3% volume concentration of nanoparticles.
It is found that the experimental Nusselt numbers for 0.1, 0.2 and 0.3% volume concentration of CuO nanoparticles are about
6, 9.9 and 12.6%, respectively higher than those obtained with distilled water in plain tube. However, the experimental Nusselt
numbers for 0.1, 0.2 and 0.3% volume concentration of CuO nanoparticles are about 3.4, 6.8 and 12%, respectively higher than
those obtained with distilled water in dimpled tube. The friction factor of CuO/water nanofluid is also increased due to the
inclusion of nanoparticles and found to increase with nanoparticle volume concentration. The experimental results show that
there exists a difference in the enhancement levels of Nusselt numbers obtained with nanofluids in plain tube and dimpled
tube. Hence it is proposed that the mechanism of heat transfer enhancement obtained with nanofluids is due to particle migration
from the core of fluid flow to tube wall. 相似文献
54.
Occurrence of strong or mass synchronization of a large number of neuronal populations in the brain characterizes its pathological states. In order to establish an understanding of the mechanism underlying such pathological synchronization, we present a model of coupled populations of phase oscillators representing the interacting neuronal populations. Through numerical analysis, we discuss the occurrence of mass synchronization in the model, where a source population which gets strongly synchronized drives the target populations onto mass synchronization. We hypothesize and identify a possible cause for the occurrence of such a synchronization, which is so far unknown: Pathological synchronization is caused not just because of the increase in the strength of coupling between the populations but also because of the strength of the strong synchronization of the drive population. We propose a demand controlled method to control this pathological synchronization by providing a delayed feedback where the strength and frequency of the synchronization determine the strength and the time delay of the feedback. We provide an analytical explanation for the occurrence of pathological synchronization and its control in the thermodynamic limit. 相似文献
55.
Dilber Pushpitha R. Bruno Chandrasekar L. Segu Sahuban Bathusha N. M. Chandramohan R. Karunakaran M. Srikumar S. R. 《Physics of the Solid State》2018,60(5):1011-1015
Physics of the Solid State - Mn doped ZnO nanorods were prepared by chemical precipitation method. The micro-structural and structural properties of the nanorods were calculated from the X-ray... 相似文献
56.
B. Chandrasekar N. Balakrishnan 《Annals of the Institute of Statistical Mathematics》2002,54(4):796-805
A multiparameter version of Tukey's (1965, Proc. Nat. Acad. Sci. U.S.A., 53, 127–134) linear sensitivity measure, as a measure of informativeness in the joint distribution of a given set of random variables, is proposed. The proposed sensitivity measure, under some conditions, is a matrix which is non-negative definite, weakly additive, monotone and convex. Its relation to Fisher information matrix and the best linear unbiased estimator (BLUE) are investigated. The results are applied to the location-scale model and it is observed that the dispersion matrix of the BLUE of the vector location-scale parameter is the inverse of the sensitivity measure. A similar property was established by Nagaraja (1994, Ann. Inst. Statist. Math., 46, 757–768) for the single parameter case when applied to the location and scale models. Two illustrative examples are included. 相似文献
57.
Focused microwave aqueous extraction of chlorophenols from solid matrices and their analysis by chromatographic techniques 总被引:2,自引:0,他引:2
Ganeshjeevan R Chandrasekar R Sugumar P Kadigachalam P Radhakrishnan G 《Journal of chromatography. A》2005,1069(2):275-280
Open-vessel focused microwave (FMW) extraction with a purely aqueous carbonate solution was used for the extraction of chlorophenols from various solid matrices. After SPE on C18-bonded silica, the analytes were determined as such by LC-UV or, as their acetyl derivatives, by GC-ECD. The FMW aqueous extraction is efficient and rapid and no organic solvents are used. PCP was detected in several solid samples, with recoveries of 101-115% (RSD, 2-4%) relative to Soxhlet extraction. Similar recoveries were obtained for the other chlorophenols for spiked samples. 相似文献
58.
Copolymers of ethyl acrylate (M1) and n-butyl methacrylate (M2) were prepared by benzoyl peroxide initiation in solution at 60° and copolymer compositions estimated by [13C]-NMR spectroscopy. The kinetic behaviour is approximately ideal with r1 = 1/r2 = 0.47. Relaxation times T1 were determined for six of the carbons in M2 units and one in the M1 units; they range from 0.07 to 1.65 sec. 相似文献
59.
60.
S. Pitchumani C. Rami Reddy S. Rajadurai K.T. Joseph M. Santappa 《European Polymer Journal》1982,18(11):949-952
Solution blending of n-butyl methacrylate-ethyl acrylate copolymers with chlorinated rubber was investigated. The tensile properties of the blends were studied; it was concluded that the blends serve as good film forming materials. 相似文献