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121.
Salaam Saleh Druthiman Reddy Mantheni Manik Pavan Kumar Maheswaram Susan Moreno-Molek Tobili Sam-Yellowe Alan T. Riga 《Journal of Thermal Analysis and Calorimetry》2013,111(3):1707-1716
Malaria affects over 500 million people worldwide leading to 1–2 million deaths each year, the majority of whom are children. Four Plasmodium species cause malaria in humans. To properly diagnose, and correctly treat malarial infections, accurate diagnosis of infection is required. Proper diagnosis of infection will result in a reduction of morbidity, mortality, and of drug resistant parasites. However, the current tests for malaria diagnosis do not efficiently identify the appropriate human and parasite biomarkers associated with disease. Detection of specific inflammatory mediators such as cytokines associated with malaria pathogenesis will aid the determination of disease progression, disease prognosis, and the early diagnosis of malaria infection. In this study, we used dielectric thermal analysis (DETA), thermogravimetric analysis, and differential scanning calorimetry (DSC) to characterize five human cytokines (IL-1α, IL-2, IL-4, IL-6, and IL-10), to demonstrate how their thermoanalytical properties can be investigated for sensor design. Analysis for DETA was performed at a frequency range of 0.1–300,000 Hz. Permittivity and loss factor measurements were used to calculate tan δ values. Peak frequencies were used to determine dielectric signatures for each cytokine. The peak frequencies were different for each cytokine analyzed. In addition, activation energies were frequency dependent for IL-2 but frequency independent for the remaining four cytokines. Cytokines were also examined using DSC which established variance in heat of crystallization and heat of fusion of solvent among the five cytokines. A noticeable differentiation was observed with IL-1α among the other four cytokines when analyzed using trend analysis. Detection of unique dielectric signals will aid development of sensitive dielectric sensors capable of detecting cytokines in various human samples. 相似文献
122.
The synthesis, characterization and analytical properties of 2-nitro-5,6-dimethyl-1,3-indanedione dithiosemicarbazone (NDIDT) are described. NDIDT is used as a chromogenic reagent for the rapid spectrophotometric determination of cobalt(II), palladium(II) and osmium(VIII). The spectrophotometric method developed for cobalt has been used in the analysis of alloys. 相似文献
123.
A facile and selective oxidation of sulfides to sulfoxides using an L‐proline–H2O2 system for structurally divergent sulfide substrates with excellent yields at ambient conditions is reported. 相似文献
124.
Symmetrically N,N′-disubstituted ureas/thioureas were synthesized by heating amines or phenyl hydrazine and urea/thiourea on a preheated hot plate at 80–85°C under solvent-free conditions in the presence of a catalytic amount of ZnCl2 as a catalyst. The protocol has the advantages of not using toxic phosgene and other hazardous substrates or organic solvents. Increased reaction rate, good yield, and a simple workup procedure are involved. 相似文献
125.
G. Venkat Reddy A. Chandra Shekhar A. Ravi Kumar G. Sathaiah B. Narsaiah P. Shanthan Rao 《Journal of heterocyclic chemistry》2012,49(3):687-690
Studies on synthetic design of 7,8‐imidazole fused fluoroquinolones from 8‐amino‐6‐fluoro‐4‐hydroxy‐N‐methyl‐7‐(methyl amino)quinoline‐3‐carboxamide and ketones/carboxylic acids and their antibacterial activity. 相似文献
126.
Alok Srivastava D. Pathania K. K. Swain Nicy Ajith R. Acharya A. V. R. Reddy H. Nayyar 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(2):315-318
The phyto-accumulation efficacy of selenium (Se) from soil by chickpea plant is reported. Chickpea plants were grown in soil having different concentrations (1–4 mg kg?1) of Se. Samples of soil and different parts of chickpea plants in Se rich soil were analyzed for determination of Se concentrations by instrumental neutron activation analysis (INAA). Samples were irradiated in self-serve facility of CIRUS reactor, BARC, Mumbai at a neutron flux of the order of 1013 cm?2 s?1. The gamma activity at 264.7 keV of 75Se (119.8 d) was measured using a 45% relative efficiency HPGe detector coupled to MCA. Dependence of Se distribution in soil and plants on its spiking concentration was evaluated in this work. The Se concentrations determined in plant parts grown in control soil and in soil spiked with Se (4 mg kg?1) are in the range of 0.6–0.8 and 65–68 mg kg?1 respectively. 相似文献
127.
S N Reddy P S Rao R V Ravikumar B J Reddy Y P Reddy 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2001,57(6):1283-1287
EPR, Optical and IR spectral studies on a naturally occurring mineral melanterite are carried out at room temperature. EPR studies indicate the presence of Cu(II) ion in tetragonally distorted octahedral site and hyperfine lines could not be resolved due to higher concentration of the paramagnetic impurity in the mineral. Optical absorption spectrum is a characteristic of Fe(II) and Cu(II) ions. Crystal field parameters are evaluated. IR spectrum confirms the presence of water and sulphate ions. 相似文献
128.
Manohar Mantipally Rambabu Gundla Madhusudhana Reddy Gangireddy Viswanathan Vijayan Velmurugan Devadasan 《Tetrahedron letters》2018,59(52):4616-4619
A novel method for the synthesis of 2-imino-2H-benzo[h]chromenes via the sequential addition of N-chlorosuccinimide and triethylamine to 2-amino-4H-benzo[h]chromenes has been established. This reaction protocol represents an efficient synthetic strategy to form iminochromene derivatives under mild reaction conditions, which utilizes readily accessible aminochromenes as starting materials and tolerates a wide range of substrates. 相似文献
129.
Sonali P. D. Bhade P. J. Reddy S. Anilkumar R. K. Singhal D. D. Rao 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(1):13-20
Liquid scintillation alpha beta discrimination technique based on pulse shape analysis (PSA) was evaluated for determination of 226Ra and 222Rn in water samples. In view of the significance of calibration, for the reliable and precise determination of 226Ra and 222Rn concentrations in water samples, calibration procedures were standardized for single and two phase systems using Quantulus 1220 liquid scintillation counter. PSA optimization and efficiency calibrations were performed using 226Ra standard rather than conventionally used pure alpha and beta standards and substantiated by measuring the activity concentrations of 226Ra and 222Rn in the spiked water samples. 相似文献
130.
Gowravaram Sabitha B. V. Subba Reddy J. S. Yadav Nishant Jain B. Jagan Mohan Reddy 《Journal of heterocyclic chemistry》2018,55(4):863-870
A series of new 1,3,4‐oxadiazole‐linked 1,2,3‐triazole/isoxazole derivatives were designed and synthesized. All the synthesized compounds were screened for in vitro anticancer activity against four human cancer cells: HeLa (cervical), MDA‐MB‐231 (breast), DU‐145 (prostate), and HEPG2 (liver). Among 17 compounds tested, 7a , 7c , and 7d showed potent activity toward four cell lines. 相似文献