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101.
Sanjushree Nagarajan Sundhar Mohandas Kumar Ganesan Baojun Xu Kunka Mohanram Ramkumar 《Molecules (Basel, Switzerland)》2022,27(19)
Pterostilbene (PTS), a compound most abundantly found in blueberries, is a natural analog of resveratrol. Several plant species, such as peanuts and grapes, produce PTS. While resveratrol has been extensively studied for its antioxidant properties, recent evidence also points out the diverse therapeutic potential of PTS. Several studies have identified the robust pharmacodynamic features of PTS, including better intestinal absorption and elevated hepatic stability than resveratrol. Indeed, due to its higher bioavailability paired with reduced toxicity compared to other stilbenes, PTS has become an attractive drug candidate for the treatment of several disease conditions, including diabetes, cancer, cardiovascular disease, neurodegenerative disorders, and aging. This review article provides an extensive summary of the nutraceutical potential of PTS in various disease conditions while discussing the crucial mechanistic pathways implicated. In particular, we share insights from our studies about the Nrf2-mediated effect of PTS in diabetes and associated complications. Moreover, we elucidate the important sources of PTS and discuss in detail its pharmacokinetics and the range of formulations and routes of administration used across experimental studies and human clinical trials. Furthermore, this review also summarizes the strategies successfully used to improve dietary availability and the bio-accessibility of PTS. 相似文献
102.
Zhen Ye Kumar Ganesan Mingquan Wu Yu Hu Yingqi She Qianqian Tian Qiaobo Ye Jianping Chen 《Molecules (Basel, Switzerland)》2022,27(21)
Breast cancer (BC) is a serious global challenge, and depression is one of the risk factors and comorbidities of BC. Recently, the research on the comorbidity of BC and depression has focused on the dysfunction of the hypothalamic–pituitary–adrenal axis and the persistent stimulation of the inflammatory response. However, the further mechanisms for comorbidity remain unclear. Epoxide metabolism has been shown to have a regulatory function in the comorbid mechanism with scattered reports. Hence, this article reviews the role of epoxide metabolism in depression and BC. The comprehensive review discloses the imbalance in epoxide metabolism and its downstream effect shared by BC and depression, including overexpression of inflammation, upregulation of toxic diols, and disturbed lipid metabolism. These downstream effects are mainly involved in the construction of the breast malignancy microenvironment through liver regulation. This finding provides new clues on the mechanism of BC and depression comorbidity, suggesting in particular a potential relationship between the liver and BC, and provides potential evidence of comorbidity for subsequent studies on the pathological mechanism. 相似文献
103.
Nitu Katariya Isha Songara Radha Krishnan Venkatesh Vedachalaiye Ganesan 《Macromolecular Symposia》2024,413(1):2300014
Recently, delafossite materials have captured the interest of numerous researchers due to their unique characteristics of p-type conductivity and transparency. These materials exhibit promising potential in various applications such as photovoltaics, sensors, and transparent electronics. This paper presents a detailed account of the preparation of CuCrO2 delafossite via the solid-state reaction method. The structural properties of the sample are analyzed using XRD which confirms rhombohedral crystal structure with R-3m space group. The optical band gap was determined to be 3.39 eV through UV-visible spectroscopy. The morphology is studied using Laser Confocal scanning optical microscopy and the estimated grain size is found to be within the range of 7 µm. 相似文献
104.
Journal of Structural Chemistry - The structure and metal complexation studies using dispersion-corrected density functional theory methods are performed for four stable glycolic acid conformers... 相似文献
105.
V.P.S. Awana Anurag Gupta E. Takayama-Muromachi M. Karppinen S.K. Malik V. Ganesan 《Solid State Communications》2004,129(2):117-121
A Tb-123 phase with the composition, TbSr2Cu2.7Mo0.3O7+δ, has been synthesized in single-phase form by the solid-state reaction route. Its phase purity has been confirmed from neutron powder diffraction studies. The as-synthesized Tb-123 sample does not show superconductivity down to 5 K. On the other hand, an unusually high antiferromagnetic ordering temperature (TN) of around 7 K is seen for the Tb moments. After 120-atm-O2 post-annealing, bulk superconductivity is achieved in this compound with a superconducting transition temperature (Tc) of about 30 K, without any significant effect on TN. To achieve higher oxygen content and higher Tc, the as-synthesized sample was subjected to high-pressure oxygenation, carried out in a closed cell, at 5 GPa and 400 °C in the presence of AgO as an excess-oxygen source. This sample exhibited superconductivity onset at around 80 K with a Meissner fraction larger than 10% at 5 K. Our observation of superconductivity at 80 K is the highest Tc to-date for the Tb-123 type compounds. 相似文献
106.
The temperature variation of the Debye-Waller factors of Cs+ and Br− ions in CsBr powder has been studied using powder X-ray diffraction. The integrated intensities of the Bragg peaks at different
temperatures have been obtained. These results have been verified by structure factor least squares refinement program. Theoretical
shell model lattice dynamical calculations have been done using a 7-parameter model in the harmonic approximation and the
values compared with the present X-ray measurements. The observed intensities have been corrected for first order thermal
diffuse scattering. 相似文献
107.
C. Ramesh G. Velayutham N. Murugesan V. Ganesan V. Manivannan G. Periaswami 《Ionics》2004,10(1-2):50-55
An improved polymer electrolyte membrane (PEM) fuel cell based amperometric hydrogen sensor that operates at room temperature
has been developed. The electrolyte used in the sensor is PVA/H3PO4 blend, which is a proton conducting solid polymer electrolyte. A blend of palladium and platinum coated on the membrane is
used as anode and platinum as cathode. The sensor functions as a fuel cell, H2/Pd-Pt//PVA-H3PO4//Pt/O2, and the short circuit current is found to be linearly related to the hydrogen concentration. The present study aims at investigating
the dependence of sensor behaviour on the anode composition.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
108.
This paper reports the investigation of mean and turbulent flow characteristics of a two-dimensional plane diffuser. Both experimental and theoretical details are considered. The experimental investigation consists of the measurement of mean velocity profiles, wall static pressure and turbulence stresses. Theoretical study involves the prediction of downstream velocity profiles and the distribution of turbulence kinetic energy using a well tested finite difference procedure. Two models, viz., Prandtl's mixing length hypothesis and k- model of turbulence, have been used and compared. The nondimensional static pressure distribution, the longitudinal pressure gradient, the pressure recovery coefficient, percentage recovery of static pressure, the variation of U
max/U
bar along the length of the diffuser and the blockage factor have been valuated from the predicted results and compared with the experimental data. Further, the predicted and the measured value of kinetic energy of turbulence have also been compared. It is seen that for the prediction of mean flow characteristics and to evaluate the performance of the diffuser, a simple turbulence model like Prandtl's mixing length hypothesis is quite adequate.List of symbols
C
1
, C
2
,C
turbulence model constants
-
F
x
body force
-
k
kinetic energy of turbulence
-
l
m
mixing length
-
L
length of the diffuser
-
u, v, w
rms value of the fluctuating velocity
-
u, v, w
turbulent component of the velocity
-
mean velocity in the x direction
-
A
average velocity at inlet
-
U
bar
average velocity in any cross section
-
U
max
maximum velocity in any cross section
-
V
mean velocity in the y direction
-
W
local width of the diffuser at any cross section
-
x, y
coordinates
-
dissipation rate of turbulence
-
m
eddy diffusivity
-
Von Karman constant
-
mixing length constant
-
l
laminar viscosity
-
eff
effective viscosity
-
v
kinematic viscosity
-
density
-
k
effective Schmidt number for k
-
effective Schmidt number for
-
stream function
-
non dimensional stream function 相似文献
109.
Marimuthu Senthilkumaran Ramesh Kumar Chitumalla Ganesan Vigneshkumar Eswaran Rajkumar Paulpandian Muthu Mareeswaran Joonkyung Jang 《Journal of inclusion phenomena and macrocyclic chemistry》2018,91(3-4):161-169
The interaction of 2,4,6-triphenylpyrylium cation with p-sulfonatocalix[4]arene is studied using absorption, emission, NMR and electrochemical techniques. The increase in the absorption is observed with the increase in the concentration of p-sulfonatocalix[4]arene. The emission intensity of 2,4,6-triphenylpyrylium cation is also enhanced in the presence of p-sulfonatocalix[4]arene. The electrochemical titration reveals the presence of host–guest interaction. The NMR analysis explains the upper rim interaction of 2,4,6-triphenypyrylium cation with p-sulfonatocalix[4]arene. The mode of binding is studied using computational methods. The quantum chemical simulations reveal the binding orientation of cationic TPP with p-SC4. The calculated complexation energy (??33.19 kcal mol?1) indicates the strong binding nature of 2,4,6-triphenylpyrylium cation with p-sulfonatocalix[4]arene. 相似文献
110.
Divya Ganesan Eman Al-Sayed Abhishek Albert Eldho Paul Abdel Nasser B. Singab 《Natural product research》2018,32(11):1274-1280
Phytochemicals serve as potential therapeutic agents for the prevention and treatment of diseases. In this study, we elucidate the renoprotective activity of compounds isolated from Eucalyptus globulus and Melaleuca styphelioides extracts in glucose- and oxalate-challenged NRK-49F cell model. The antioxidant potential of isolated compounds was evaluated based on their effect on antioxidant enzyme activities and lipid peroxidation levels. The results demonstrated that exposure of NRK-49F cells to glucose and oxalate stress augmented cell damage and attenuated antioxidant enzyme activities. The phytochemicals 2,2,8-trimethyl-6-formyl-chrom-3-ene-7-O-β-D-glucopyranoside, Cornusiin B and tellimagrandin I treatment restored antioxidant enzyme activity, significantly lowered lipid peroxidation levels and effectively protected cells from glucose and oxalate stress equivalent to the known antioxidant, N-acetyl cysteine. Pterocarinin A significantly reversed cellular damage owing to glucose stress. In conclusion, the compounds isolated from E. globulus and M. styphelioides showed potential cytoprotective and anti-oxidative property against glucose- and oxalate-induced oxidative stress in NRK-49F cells. 相似文献