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11.
Monisha Prasad Selvaraj Jayaraman Mohamed Ahmed Eladl Mohamed El-Sherbiny Mosaab Abdella Ebrahim Abdelrahman Vishnu Priya Veeraraghavan Srinivasan Vengadassalapathy Vidhya Rekha Umapathy Shazia Fathima Jaffer Hussain Kalaiselvi Krishnamoorthy Durairaj Sekar Chella Perumal Palanisamy Surapaneni Krishna Mohan Ponnulakshmi Rajagopal 《Molecules (Basel, Switzerland)》2022,27(5)
Natural products in the form of functional foods have become increasingly popular due to their protective effects against life-threatening diseases, low risk of adverse effects, affordability, and accessibility. Plant components such as phytosterol, in particular, have drawn a lot of press recently due to a link between their consumption and a modest incidence of global problems, such as Type 2 Diabetes mellitus (T2DM), cancer, and cardiovascular disease. In the management of diet-related metabolic diseases, such as T2DM and cardiovascular disorders, these plant-based functional foods and nutritional supplements have unquestionably led the market in terms of cost-effectiveness, therapeutic efficacy, and safety. Diabetes mellitus is a metabolic disorder categoriszed by high blood sugar and insulin resistance, which influence major metabolic organs, such as the liver, adipose tissue, and skeletal muscle. These chronic hyperglycemia fallouts result in decreased glucose consumption by body cells, increased fat mobilisation from fat storage cells, and protein depletion in human tissues, keeping the tissues in a state of crisis. In addition, functional foods such as phytosterols improve the body’s healing process from these crises by promoting a proper physiological metabolism and cellular activities. They are plant-derived steroid molecules having structure and function similar to cholesterol, which is found in vegetables, grains, nuts, olive oil, wood pulp, legumes, cereals, and leaves, and are abundant in nature, along with phytosterol derivatives. The most copious phytosterols seen in the human diet are sitosterol, stigmasterol, and campesterol, which can be found in free form, as fatty acid/cinnamic acid esters or as glycosides processed by pancreatic enzymes. Accumulating evidence reveals that phytosterols and diets enriched with them can control glucose and lipid metabolism, as well as insulin resistance. Despite this, few studies on the advantages of sterol control in diabetes care have been published. As a basis, the primary objective of this review is to convey extensive updated information on the possibility of managing diabetes and associated complications with sterol-rich foods in molecular aspects. 相似文献
12.
The pressure dependence of thelo-to phonons in InAs has been investigated by Raman scattering using the diamond anvil cell. Indium arsenide transforms, presumably
to the rock-salt structure at 70±1 kbar. The mode Grüneisen parameters for thelo-to phonons are γ
lo
=0.99±0.03, γ
to
=1.2±0.03 respectively. The effective charge,e*
T
, for InAs decreases slightly with pressure and this trend is in accordance with the behaviour of other III–V zinc blende
structured semiconductors: The structural phase transition is discussed in the light of theoretical calculations for phase
stability of III–V compounds, as well as recent high pressure x-ray diffraction studies. 相似文献
13.
The pressure dependence of the direct and indirect bandgap of epitaxial In0.52Al0.48As on InP(001) substrate has been measured using photoluminescence up to 92 kbar hydrostatic pressure. The bandgap changes
from Γ toX at an applied pressure of ∼ 43 kbar. Hydrostatic deformation potentials for both the Γ andX bandgaps are deduced, after correcting for the elastic constant (bulk modulus) mismatch between the epilayer and the substrate.
For the epilayer we obtain
and+(2.81±0.15)eV for the Γ andX bandgaps respectively. From the pressure dependence of the normalized Γ-bandgap photoluminescence intensity a Γ-X lifetime ratio, (τΓ/τ
X
), of 4.1×10−3 is deduced. 相似文献
14.
Oligonucleic acids (ONAs), such as DNA and RNA, are used in various biotechnology and nanotechnology applications due to their ability to form a double helix that is stable at low temperature and melts at high temperatures. The melting temperature (Tm) of ONA duplexes can be tuned by the ONA composition, sequence, length and concentration, solvent quality, and salt concentration and by conjugation to other macromolecules. In this article, we use coarse‐grained (CG) molecular simulations to study ONAs conjugated with linear homopolymers that are relatively more solvophobic than the ONA. We study charged and stiff 8‐mer ONAs (e.g., DNA) and neutral and flexible 8‐mer ONAs (e.g., peptide nucleic acids or PNA), and vary the composition (or G‐C content) and sequence of ONA, conjugated homopolymer lengths and solvent quality for the polymer. For neutral and flexible ONAs, as the solvent quality worsens for the polymer, the ONA melting temperature increases from that of unconjugated ONA. The melting curves broaden with polymer length and worsening solvent quality, especially for ONAs with higher G‐C content. For charged and stiff ONAs, as the solvent quality worsens, the ONA melting temperature decreases compared to unconjugated ONA while the width of the melting curve remains the same. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 1196–1208 相似文献
15.
A. Jayaraman J.P. Remeika G.P. Espinosa A.S. Cooper H. Barz R.G. Maines Z. Fisk 《Solid State Communications》1981,39(10):1049-1051
The ternary compound YbRh1.4Sn4.6 with the phase I structure (simple cubic) when subjected to a pressure of 40 kbar at 800°C is found to transform to phase III structure (f.c.c.) with the composition YbRh1.1Sn3. The latter compound has a lattice parameter of which suggests that the Yb is in an intermediate valence state. The temperature dependence of magnetic susceptibility suggests that the Yb is in a homogeneously mixed valence state in the pressure synthesized product. In the phase I structure YbRh1.1Sn4.6 is superconducting at 8.6°K, but in the phase III structure the compound YbRh1.1Sn3 is not superconducting down to 0.9°K. It is suggested that superconductivity and mixed valence are incompatible. 相似文献
16.
P. S. Verma T. Venkateshwar Rao A. Jayaraman P. S. N. Murthy G. C. Joshi 《Fresenius' Journal of Analytical Chemistry》1994,348(11):742-744
The Fe(III)-EDTA complex reacts with sulfide ion in a fast electron transfer reaction, oxidising the latter to elemental sulfur and getting itself reduced to Fe(II). The reaction has been developed for the quantitative estimation of sulfide ion by titration against the Fe(III)-EDTA complex, measuring the redox potential of the system. Repeated use of a given quantity of the complex solution by the process of regeneration has been demonstrated. The possibility of its practical application in liquid phase oxidation processes of recovering sulfur from H2S is emphasized. 相似文献
17.
Synthesis and Langmuir studies of bivalent and monovalent alpha-D-mannopyranosides with lectin Con A
Bandaru NM Sampath S Jayaraman N 《Langmuir : the ACS journal of surfaces and colloids》2005,21(21):9591-9596
Highly avid interaction between carbohydrate ligands and lectin receptors nominally requires the ligand presentation in a clustered form. We present herein an approach involving Langmuir monolayer formation of the sugar ligands and the assessment of their lectin binding at the air-water interface. Bivalent alpha-D-mannopyranoside containing the glycolipid ligand was used to study its binding profiles with lectin Con A, in comparison to the corresponding monovalent glycolipid. In addition to the bivalent and monovalent nature of the glycolipid ligands at the molecular level, the ligand densities at the monolayer level were varied with the aid of a nonsugar lipid molecule so as to obtain mixed monolayers with various sugar-nonsugar ratios. Lectin binding of bivalent and monovalent ligands at different ratios was monitored by differential changes in the surface area per molecule of the mixed monolayer, with and without the lectin. The present study shows that maximal binding of the lectin to the bivalent ligand occurs at lower sugar densities at the interface ( approximately 10% sugar in the mixed monolayer) than for that of the monovalent ligand ( approximately 20% sugar in the mixed monolayer). It is observed that complete coverage of the monolayer with only the sugar ligands does not allow all of the sugars to be functionally active. 相似文献
18.
19.
Dessingou J Tabbasum K Mitra A Hinge VK Rao CP 《The Journal of organic chemistry》2012,77(3):1406-1413
The structurally characterized lower rim 1,3-di{4-antipyrine}amide conjugate of calix[4]arene (L) exhibits high selectivity toward Hg(2+) among other biologically important metal ions, viz., Na(+), K(+), Ca(2+), Mg(2+), Mn(2+), Fe(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+), Pb(2+), and Ag(+) as studied by fluorescence, absorption, and ESI MS. L acts as a sensor for Hg(2+) by switch-off fluorescence and exhibits a lowest detectable concentration of 1.87 ± 0.1 ppm. The complex formed between L and Hg(2+) is found to be 1:1 on the basis of absorption and fluorescence titrations and was confirmed by ESI MS. The coordination features of the mercury complex of L were derived on the basis of DFT computations and found that the Hg(2+) is bound through an N(2)O(2) extending from both the arms to result in a distorted octahedral geometry with two vacant sites. The nanostructural features such as shape and size obtained using AFM and TEM distinguishes L from its Hg(2+) complex and were different from those of the simple mercuric perchlorate. L is also suited to sense pyrimidine bases by fluorescence quenching with a minimum detection limit of 1.15 ± 0.1 ppm in the case of cytosine. The nature of interaction of pyrimidine bases with L has been further studied by DFT computational calculations and found to have interactions through a hydrogen bonding and NH-π interaction between the host and the guest. 相似文献
20.
Multilayer thin film coatings were prepared on silicon substrates. Poly(vinyl alcohol) was adsorbed from aqueous solution to propyldimethylsilyl-modified silicon wafers. This thin semicrystalline coating was chemically modified using acid chlorides to form thicker, hydrophobic coatings. The products of the modification reactions allowed adsorption of a subsequent layer of poly(vinyl alcohol) that could subsequently be hydrophobized. This two-step process (adsorption/chemical modification) allows layer-by-layer deposition to prepare coatings with thickness, chemical structure, and wettability control. 相似文献