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Suman Som Gourab Dutta Banik Abhijit Maity Chiranjit Ghosh Sujit Chaudhuri 《Isotopes in environmental and health studies》2018,54(4):435-445
Helicobacter pylori causes several gastrointestinal diseases and may also contribute to the development of type 2 diabetes (T2D). Several studies suggest that there might be a potential link between H. pylori infection and T2D, but it still remains the subject of debate. Here, we first report the cumulative effect of H. pylori infection and T2D by exploiting the excretion kinetics of 13C/12C and 18O/16O isotope ratios of exhaled breath CO2 in response to an oral dose of 13C-enriched glucose in individuals with T2D and non-diabetic controls (NDC) harbouring the H. pylori infection. Using a high-resolution integrated cavity output spectroscopy (ICOS) technique in the infrared region, we observed that the isotopic fractionations of 13C and 18O in breath CO2 are distinctly altered in H. pylori infected T2D patients as well as in H. pylori infected NDC. Several optimal diagnostic cut-off points of 13C and 18O isotopes of breath CO2 were also determined which exhibited the diagnostic sensitivity and specificity of ~97?% and thus suggesting that breath 13C and 18O isotopes might be considered as potential biomarkers for the non-invasive assessment of the gastric pathogen prior to the onset of T2D. This may open a new diagnostic strategy for treating these common diseases in an alternative way. 相似文献
393.
Pranesh Kumar Atul Rawat Amit K. Keshari Ashok K. Singh Siddhartha Maity Arnab De 《Natural product research》2016,30(4):460-463
The present study was undertaken to investigate the antiproliferative action of isolated M1 (6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid) from Mucuna pruriens seeds using human hepatic carcinoma cell line (Huh-7 cells). Initially, docking studies was performed to find out the binding affinities of M1 to caspase-3 and 8 enzymes. Later, cytotoxic action of M1 was measured by cell growth inhibition (MTT), followed by caspase-3 and 8 enzymes assay colorimetrically. Our results collectively suggested that M1 had strong binding affinity to caspase-8 in molecular modelling. M1 possessed antiproliferative activity on Huh-7 cells (EC50 = 13.97 μM) and also inhibited the action of caspase-8 enzyme, signified process of apoptosis. M1 was active against Huh-7 cells that may be useful for future hepatic cancer treatment. 相似文献
394.
Adsorption of rhodamine B on Rhizopus oryzae: role of functional groups and cell wall components 总被引:1,自引:0,他引:1
The role of different functional groups (i.e. amino, carboxyl, hydroxyl as well as phosphate) and cell wall components (such as chitin, chitosan, glucan and phosphomannan) of Rhizopus oryzae on adsorption of rhodamine B is described. The functional groups were chemically modified to determine their contribution in the present adsorption process. Fourier transformed infrared spectroscopic (FTIR) study was used to characterize the modification of the functional groups due to chemical treatments. Carboxyl and amino groups were identified as most important moieties involved in the binding process. Different cell wall components were also isolated from the cell wall to explore their role involved in the binding process. Phosphomannan fraction adsorbed higher amounts of rhodamine B compared to the other cell wall components. Fluorescence microscopic images also supported the differential adsorption capacity of the various cell wall components. 相似文献
395.
Two ortho-phenylenediamine-based new receptors 1 and 2 with an anthracene-coupled benzimidazolium motif have been designed and synthesized. The directed hydrogen bonds (both conventional and unconventional) and charge-charge interactions allowed the open clefts of both 1 and 2 to bind carboxylate, fluoride and dihydrogenphosphate anions with moderate binding constant values. The selectivity and sensitivity were ascertained by 1H NMR, UV-vis and fluorescence spectroscopic methods. The binding cleft of 2 is found to be more effective than that of 1. 相似文献
396.
A new, convenient and mild method for thioacetalization of heterocyclic, aromatic and aliphatic compounds catalyzed by MoCl5 or MoO2Cl2 is described. This novel method is important for the synthesis of the difficult to prepare heterocyclic thioacetals such as the pterin thioacetals and it offers significant advantages such as high conversion, short reaction times and simplicity in operation. 相似文献
397.
Daipayan Dutta Dipankar Maity Mahammad Ali Michael G. B. Drew Swastik Mondal Monika Mukherjee 《Transition Metal Chemistry》2008,33(3):347-351
A novel bis(glycinato)copper(II)paradodecatungstate Na8[{Cu(gly)2}2]-{H2(H2W12O42)}] · 24H2O (1) has been synthesized under hydrothermal conditions. The crystal structure of 1 reveals an infinite one-dimensional chain along the [100] direction and is built from paradodecatungstate (H2W12O42)10− clusters joined through [Cu(gly)2] moieties. Parallel chains are interlinked by NaO6 octahedra to generate a two-dimensional network. 相似文献
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In this paper, analogous to chance constraints, real-life necessity and possibility constraints in the context of a multi-item dynamic production-inventory control system are defined and defuzzified following fuzzy relations. Hence, a realistic multi-item production-inventory model with shortages and fuzzy constraints has been formulated and solved for optimal production with the objective of having minimum cost. Here, the rate of production is assumed to be a function of time and considered as a control variable. Also the present system produces some defective units along with the perfect ones and the rate of produced defective units is constant. Here demand of the good units is time dependent and known and the defective units are of no use. The space required per unit item, available storage space and investment capital are assumed to be imprecise. The space and budget constraints are of necessity and/or possibility types. The model is formulated as an optimal control problem and solved for optimum production function using Pontryagin’s optimal control policy, the Kuhn–Tucker conditions and generalized reduced gradient (GRG) technique. The model is illustrated numerically and values of demand, optimal production function and stock level are presented in both tabular and graphical forms. The sensitivity of the cost functional due to the changes in confidence level of imprecise constraints is also presented. 相似文献