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81.
Kaviyarasi Renu Anirban Goutam Mukherjee Uddesh Ramesh Wanjari Sathishkumar Vinayagam Vishnu Priya Veeraraghavan Balachandar Vellingiri Alex George Ricardo Lagoa Kamaraj Sattu Abhijit Dey Abilash Valsala Gopalakrishnan 《Molecules (Basel, Switzerland)》2022,27(17)
Heavy metals and metalloids like cadmium, arsenic, mercury, and lead are frequently found in the soil, water, food, and atmosphere; trace amounts can cause serious health issues to the human organism. These toxic trace elements (TTE) affect almost all the organs, mainly the heart, kidney, liver, lungs, and the nervous system, through increased free radical formation, DNA damage, lipid peroxidation, and protein sulfhydryl depletion. This work aims to advance our understanding of the mechanisms behind lipid accumulation via increased free fatty acid levels in circulation due to TTEs. The increased lipid level in the myocardium worsens the heart function. This dysregulation of the lipid metabolism leads to damage in the structure of the myocardium, inclusive fibrosis in cardiac tissue, myocyte apoptosis, and decreased contractility due to mitochondrial dysfunction. Additionally, it is discussed herein how exposure to cadmium decreases the heart rate, contractile tension, the conductivity of the atrioventricular node, and coronary flow rate. Arsenic may induce atherosclerosis by increasing platelet aggregation and reducing fibrinolysis, as exposure interferes with apolipoprotein (Apo) levels, resulting in the rise of the Apo-B/Apo-A1 ratio and an elevated risk of acute cardiovascular events. Concerning mercury and lead, these toxicants can cause hypertension, myocardial infarction, and carotid atherosclerosis, in association with the generation of free radicals and oxidative stress. This review offers a complete overview of the critical factors and biomarkers of lipid and TTE-induced cardiotoxicity useful for developing future protective interventions. 相似文献
82.
Koushik Dhara Santanu Karan Jagnyeswar Ratha Partha Roy Goutam Chandra Mario Manassero Dr. Biswanath Mallik Dr. Pradyot Banerjee Dr. 《化学:亚洲杂志》2007,2(9):1091-1100
A 2D coordination compound {[Cu2(HL)(N3)]?ClO4}∞ ( 1 ; H3L=2,6‐bis(hydroxyethyliminoethyl)‐4‐methyl phenol) was synthesized and characterized by single‐crystal X‐ray diffraction to be a polymer in the crystalline state. Each [Cu2(HL)(N3)]+ species is connected to its adjacent unit by a bridging alkoxide oxygen atom of the ligand to form a helical propagation along the crystallographic a axis. The adjacent helical frameworks are connected by a ligand alcoholic oxygen atom along the crystallographic b axis to produce pleated 2D sheets. In solution, 1 dissociates into [Cu2(HL)2(H3L)]?2H2O ( 2 ); the monomer displays high selectivity for Zn2+ and can be used in HEPES buffer (pH 7.4) as a zinc ion selective luminescent probe for biological application. The system shows a nearly 19‐fold Zn2+‐selective chelation‐enhanced fluorescence response in the working buffer. Application of 2 to cultured living cells (B16F10 mouse melanoma and A375 human melanoma) and rat hippocampal slices was also studied by fluorescence microscopy. 相似文献
83.
The aim of this paper is to investigate the problem of MHD flow of two immiscible viscoelastic Rivlin-Ericksen fluids through a non-conducting rectangular channel in presence of transient pressure gradient. Appropriate to the boundary conditions of the problem the solution is derived by variable separation technique. Using this solution the interface velocity, flux, skin friction and mean velocity are derived. In absence of the magnetic field and the elastic behaviour the corresponding classical problem can be derived. 相似文献
84.
Raj Gandhi Subhendra Mohanty Tarun Souradeep S Agarwalla K Bhattacharya B Brahmachari R Crittenden S Goswami P Ghoshal M Lindner H S Mani S Mitra S Pascoli S Panda R Rangarajan S Ray T Roy Choudhury R Saha S Sarkar A Srivastava R Sheth S Uma Sankar U Yajnik 《Pramana》2006,67(4):735-742
The working group on astroparticle and neutrino physics at WHEPP-9 covered a wide range of topics. The main topics were neutrino
physics at INO, neutrino astronomy and recent constraints on dark energy coming from cosmological observations of large scale
structure and CMB anisotropy. 相似文献
85.
Poole JS Hadad CM Platz MS Fredin ZP Pickard L Guerrero EL Kessler M Chowdhury G Kotandeniya D Gates KS 《Photochemistry and photobiology》2002,75(4):339-345
The absorption and fluorescence spectra of 3-aminobenzo-1,2,4-triazine di-N-oxide (tirapazamine) have been recorded and exhibit a dependence on solvent that correlates with the Dimroth ET30 parameter. Time-dependent density functional theory calculations reveal that the transition of tirapazamine in the visible region is pi-->pi* in nature. The fluorescence lifetime is 98+/-2 ps in water. The fluorescence quantum yield is approximately 0.002 in water. The fluorescence of tirapazamine is efficiently quenched by electron donors via an electron-transfer process. Linear Stern-Volmer fluorescence quenching plots are observed with sodium azide, potassium thiocyanate, guanosine monophosphate and tryptophan (Trp) methyl ester hydrochloride. Guanosine monophosphate, tyrosine (Tyr) methyl ester hydrochloride and Trp methyl ester hydrochloride appear to quench the fluorescence at a rate greater than diffusion control implying that these substrates complex with tirapazamine in its ground state. This complexation was detected by absorption spectroscopy. 相似文献
86.
87.
Highly Crystalline Mesoporous C60 with Ordered Pores: A Class of Nanomaterials for Energy Applications
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Mercy R. Benzigar Stalin Joseph Hamid Ilbeygi Dr. Dae‐Hwan Park Dr. Sujoy Sarkar Dr. Goutam Chandra Prof. Siva Umapathy Prof. Sampath Srinivasan Dr. Siddulu Naidu Talapaneni Prof. Ajayan Vinu 《Angewandte Chemie (International ed. in English)》2018,57(2):569-573
Highly ordered mesoporous C60 with a well‐ordered porous structure and a high crystallinity is prepared through the nanohard templating method using a saturated solution of C60 in 1‐chloronaphthalene (51 mg mL?1) as a C60 precursor and SBA‐15 as a hard template. The high solubility of C60 in 1‐chloronaphthalene helps not only to encapsulate a huge amount of the C60 into the mesopores of the template but also supports the oligomerization of C60 and the formation of crystalline walls made of C60. The obtained mesoporous C60 exhibits a rod‐shaped morphology, a high specific surface area (680 m2 g?1), tuneable pores, and a highly crystalline wall structure. This exciting ordered mesoporous C60 offers high supercapacitive performance and a high selectivity to H2O2 production and methanol tolerance for ORR. This simple strategy could be adopted to make a series of mesoporous fullerenes with different structures and carbon atoms as a new class of energy materials. 相似文献
88.
89.
Goutam Mukherjee 《Proceedings of the American Mathematical Society》1997,125(4):1229-1236
We determine conditions for a -CW-complex to be a Hopfian or a co-Hopfian object in the -homotopy category of -path-connected -CW-complexes with base points.
90.
Sandeep Ghumaan Biprajit Sarkar Mahendra P. Patil Jan Fiedler Raghavan B. Sunoj Wolfgang Kaim Goutam Kumar Lahiri 《Polyhedron》2007
The complexes (μ3-L1/L2)[Ru(acac)2]3, acac− = 2,4-pentanedionato, L1 = 2,3,8,9,14,15-hexachlorodiquinoxalino[2,3-a:2′,3′-c]phenazine and L2 = 2,3,8,9,14,15- hexamethyldiquinoxalino[2,3-a:2′,3′-c]phenazine, undergo stepwise one-electron oxidation involving a total of three electrons and stepwise one-electron reduction with three (L2) or four electrons (L1). All reversibly accessible states were characterized by UV–Vis–NIR spectroelectrochemistry. Oxidation leads to mixed-valent intermediates {(μ3-L)[Ru(acac)2]3}+ and {(μ3-L)[Ru(acac)2]3}2+ of which the RuIIIRuIIRuII combinations exhibit higher comproportionation constants Kc than the RuIIIRuIIIRuII states – in contrast to a previous report for the unsubstituted parent systems {(μ3-L3)[Ru(acac)2]3}+/2+, L3 = diquinoxalino[2,3-a:2′,3′-c]phenazine. No conspicuous inter-valence charge transfer absorptions were observed for the mixed-valent intermediates in the visible to near-infrared regions. The monocations and monoanions were characterized by EPR spectroscopy, revealing rhombic ruthenium(III) type signals for the former. Electron addition produces ruthenium(II) complexes of the reduced forms of the ligands L, a high resolution EPR spectrum with 14N and 35,37Cl hyperfine coupling and negligible g anisotropy was found for {(μ3-L1)[Ru(acac)2]3}−. DFT calculations of (μ3-L1)[Ru(acac)2]3 confirm several ligand-centered low-lying unoccupied MOs for reduction and several metal-based high-lying occupied MOs for electron withdrawal, resulting in low-energy metal-to-ligand charge transfer (MLCT) transitions. 相似文献