16 research outputs found
Development of a Fast SARS-CoV-2 IgG ELISA, Based on Receptor-Binding Domain, and Its Comparative Evaluation Using Temporally Segregated Samples From RT-PCR Positive Individuals
SARS-CoV-2 antibody detection assays are crucial for gathering seroepidemiological information and monitoring the sustainability of antibody response against the virus. The SARS-CoV-2 Spike protein's receptor-binding domain (RBD) is a very specific target for anti-SARS-CoV-2 antibodies detection. Moreover, many neutralizing antibodies are mapped to this domain, linking antibody response to RBD with neutralizing potential. Detection of IgG antibodies, rather than IgM or total antibodies, against RBD is likely to play a larger role in understanding antibody-mediated protection and vaccine response. Here we describe a rapid and stable RBD-based IgG ELISA test obtained through extensive optimization of the assay components and conditions. The test showed a specificity of 99.79% (95% CI: 98.82-99.99%) in a panel of pre-pandemic samples (n = 470) from different groups, i.e., pregnancy, fever, HCV, HBV, and autoantibodies positive. Test sensitivity was evaluated using sera from SARS-CoV-2 RT-PCR positive individuals (n = 312) and found to be 53.33% (95% CI: 37.87-68.34%), 80.47% (95% CI: 72.53-86.94%), and 88.24% (95% CI: 82.05-92.88%) in panel 1 (days 0-13), panel 2 (days 14-20) and panel 3 (days 21-27), respectively. Higher sensitivity was achieved in symptomatic individuals and reached 92.14% (95% CI: 86.38-96.01%) for panel 3. Our test, with a shorter runtime, showed higher sensitivity than parallelly tested commercial ELISAs for SARS-CoV-2-IgG, i.e., Euroimmun and Zydus, even when equivocal results in the commercial ELISAs were considered positive. None of the tests, which are using different antigens, could detect anti-SARS-CoV-2 IgGs in 10.5% RT-PCR positive individuals by the fourth week, suggesting the lack of IgG response
Tomographic Reconstruction of Emissivity Profile from Tangentially Viewed Images using Pixel Method
A randomised, double-blind, comparative study of preoperative magnesium sulphate versus zinc sulphate gargle for prevention of postoperative sore throat following endotracheal intubation
Background and Aims: Magnesium sulphate and zinc sulphate have been reported to attenuate postoperative sore throat (POST). The study aims to compare the effect of preoperative magnesium sulphate and zinc sulphate gargle on the incidence and severity of POST following endotracheal intubation within 24 h. Methods: After ethics committee approval, 132 patients were randomly allocated to three groups (M, Z and D). Fifteen minutes before laryngoscopy and tracheal intubation, patients assigned to groups M and Z received a solution for gargle containing magnesium sulphate 20 mg/kg and zinc sulphate containing 40 mg of elemental zinc dissolved in 20 ml of 5% dextrose solution, respectively. Group D received 20 ml of 5% dextrose solution. Incidence and severity of POST (4-point score: Grade 0- no sore throat, Grade 1- mild sore throat, Grade 2- moderate sore throat, Grade 3- severe sore throat) was assessed for 24 h after extubation. Statistica, Version 8.0 (StatSoft, Inc., Tulsa, Oklahoma, USA) was used for analysing the data. Results: The lowest incidence of POST in group M was 13.6% (95% confidence interval [CI] 3.5–23.7) compared to 0% in group Z, whereas the highest incidence recorded in group M was 25% (95% CI 12.2–37.7) in contrast to 13.6% (95% CI 3.5–23.7) in group Z during the first 24 h after operation. It was observed that the incidence of mild POST (POST score 1) was significantly lower (P < 0.05) in group Z compared to group M in the first 4 h postoperatively. Conclusion: Zinc sulphate gargle before laryngoscopy and tracheal intubation is more effective for reducing the incidence of POST than magnesium sulphate gargle
Photophysics of a novel bichromophoric molecule: 9-Chloro-10, 10'-bis(dichloromethyleno)-(9'H)-10, 10'-dihydro-9, 9'-bianthryl
195-205The absorption and fluorescence of 9-chloro-10, 10'-bis-(dichloromdhyleno )-(9'H)-10, 10'-dihydro 9.9'-bianthryl (CDDB) and its photophysics in a number of solvents have been studied. In polar solvents CDDB gives enormous Stokes' shift and dual fluorescence from two different excited states namely R state and P state. The formation of a TICT (twisted intramolecular charge transfer) state is confirmed from the measurements of excited state dipole moments, lifetimes and deactivation pathways. The equilibrium between Rand P states has also been determined. To explain the enormous Stokes' shift, photoisomerization of CDDB is considered as an alternate model other than TICT model. Benzene forms charge transfer complex with CDDB in the ground state, whereas in the excited state. this interaction is enhanced
A new functionalized mesoporous matrix supported Pd(II)-Schiff base complex: an efficient catalyst for the Suzuki Miyaura coupling reaction
[EN] A new Pd(II) bounded 2D-hexagonally ordered functionalized MCM-41 type material (IV) has been synthesized. Functionalization was carried out by the anchoring of 3-aminopropyltriethoxysilane in the MCM-41 type mesoporous material, followed by grafting with 2,6-diacetylpyridine (DAP) to give a N-3-type Schiff base chelating attachment for the Pd(II) species. Fourier transform infrared (FTIR), powder X-ray diffraction (PXRD) and high resolution transmission electron microscopy (HRTEM) studies have been used to characterize the material. Material IV behaves as a highly active catalyst towards Suzuki-Miyaura cross-coupling reaction for the synthesis of biaryl organics. In addition, IV acts as a true heterogeneous catalyst in coupling reaction. It was found that this catalyst is highly efficient and recyclable towards Suzuki-Miyaura reaction with high turn over frequencies. X-Ray photoelectron spectroscopic (XPS) analysis was employed to understand the oxidation state of the palladium atom in the catalyst (IV) and its loading in the material.PC acknowledges Department of Science and Technology (DST), New Delhi for financial support.Dhara, K.; Sarkar, K.; Srimani, D.; Saha, SK.; Chattopadhyay, P.; Bhaumik, A. (2010). A new functionalized mesoporous matrix supported Pd(II)-Schiff base complex: an efficient catalyst for the Suzuki Miyaura coupling reaction. Dalton Transactions. 39(28):6395-6402. doi:10.1039/c003142aS63956402392
Analysis of disruptive instabilities in Aditya tokamak discharges
826-833Major disruptions
and sawteeth oscillations (internal disruptions) are routinely observed in
ohmically heated Aditya tokamak discharges and their characteristics have been
investigated with the help of soft X-ray (SXR) tomography along with other
diagnostics. The SXR tomography is carried out with the help of single array of
detectors assuming rigid rotation of the modes to analyse the mode structure of
sawtooth internal disruptions. Coupling of m/n=2/1
and m/n=1/1 modes could be the main
mechanism for the major disruption. Sawteeth periods were measured and compared
with the scaling laws and found to be in good agreement
Effect of annealing temperature on the sensitivity of thin dioxide films prepared via a sulphide route
“Seeing” invisible volatile organic compound (VOC) marker of urinary bladder cancer:A development from bench to bedside prototype spectroscopic device
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Non-invasive estimation of hemoglobin, bilirubin and oxygen saturation of neonates simultaneously using whole optical spectrum analysis at point of care
The study was aimed to evaluate the performance of a newly developed spectroscopy-based non-invasive and noncontact device (SAMIRA) for the simultaneous measurement of hemoglobin, bilirubin and oxygen saturation as an alternative to the invasive biochemical method of blood sampling. The accuracy of the device was assessed in 4318 neonates having incidences of either anemia, jaundice, or hypoxia. Transcutaneous bilirubin, hemoglobin and blood saturation values were obtained by the newly developed instrument which was corroborated with the biochemical blood tests by expert clinicians. The instrument is trained using Artificial Neural Network Analysis to increase the acceptability of the data. The artificial intelligence incorporated within the instrument determines the disease condition of the neonate. The Pearson's correlation coefficient, r was found to be 0.987 for hemoglobin estimation and 0.988 for bilirubin and blood gas saturation respectively. The bias and the limits of agreement for the measurement of all the three parameters were within the clinically acceptance limit