Browsing by Author "Neha Gupta"

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A highly sensitive and selective piezoelectric molecularly imprinted sensor for RGD peptides
(American Scientific Publishers, 2016) Neha Gupta; Archana Kushwaha; Meenakshi Singh
A piezoelectric molecularly imprinted polymeric sensor of a peptide, arg-gly-asp (RGD) is fabricated in this work. Gold-coated quartz crystals were used as piezoelectric platform for grafting RGDimprinted film. 3-mercaptopropionic acid was used to generate carboxyl groups on gold surface via thiol chemistry; which was activated by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxylsuccinimide (NHS). RGD peptides were subsequently grafted on such activated carboxyl groups. Methacrylic acid (MAA), ethylene glycol dimethacrylate (EGDMA) and azo-isobutyronitrile (AIBN) were used as functional monomer, crosslinker and initiator, respectively. On extraction of RGD peptides from thus grafted polymeric film, selective and sensitive receptor sites were generated on MIP-coated EQCM crystals. Hence, an electrochemical quartz crystal microbalance (EQCM)-MIP sensor with imprinting factor (IF) 2.27 for peptide was fabricated in a facile manner with detection limit of 18.5 ng mL-1 (3σ). Thus fabricated sensor was successfully applied in 'real' samples of blood plasma also. Copyright © 2016 American Scientific Publishers All rights reserved Printed in the United States of America.
A prospective randomized comparison of simultaneous integrated boost with sequential boost intensity-modulated radiotherapy in locally advanced head and neck cancer
(Wolters Kluwer Medknow Publications, 2022) Nilesh Mani; Sushil K. Aggarwal; Ishan Kumar; Abhijit Mandal; Garima Jaiswal; Rakesh Ranjan; Anil K. Jaiswal; Neha Gupta; Ankita Singh; Ankur Mourya; Lalit M. Aggarwal; Sunil Choudhary
Purpose: A comparison of simultaneous integrated boost (SIB) with sequential boost (SEQ) using intensity-modulated radiotherapy along with concurrent cisplatin in locally advanced head and neck cancer (HNC) was made with regard to their survival outcomes and toxicity profile. Materials and Methods: A total of 34 patients were enrolled between October 2016 and March 2019. They were randomized into two arms, SIB and SEQB. All patients were treated with 6 MV photon beam on Linear Accelerator with weekly concurrent cisplatin at 35 mg/m 2. Overall survival (OS) and disease-free survival (DFS) were the primary end points and acute and late toxicities were the secondary end points. Results: The median follow-up period was 40.6 and 37.3 months for SIB and SEQB, respectively. At the end of 5 years, the median OS was 40.6 and 37.3 months (P = 0.947) and the median DFS was 35.1 and 37.3 months in the SIB and SEQB arms, respectively (P = 0.991).complete response at 3 months was 64.7% and 76.5% and partial response was 23.5% and 17.6%, whereas progressive disease was 11.8% and 5.9% in SIB and SEQB arms, respectively. Acute dermatitis, mucositis, dysphagia, and salivary gland toxicities were higher in the SIB arm compared to the SEQB arm. Conclusion: SIB and SEQ arms were comparable in terms of OS and DFS. However, the acute toxicities were higher in the SIB arm, although the difference was not significant, compared to the SEQB arm. © 2022 Wolters Kluwer Medknow Publications. All rights reserved.
Acute hepatitis E in India appears to be caused exclusively by genotype 1 hepatitis E virus
(Indian Society of Gastroenterology, 2018) Neha Gupta; Aditya N. Sarangi; Sunil Dadhich; V.K. Dixit; Kamal Chetri; Amit Goel; Rakesh Aggarwal
Background: Hepatitis E is caused by infection with hepatitis E virus (HEV), which has four well-known genotypes. Genotypes 1 and 2 HEV have been reported from human cases in areas where the disease is highly endemic. By contrast, genotypes 3 and 4 HEV, which primarily infect several animal species worldwide, have been reported mainly from sporadic human cases in non-endemic areas such as Japan and high-income countries of Europe and North America. To determine whether genotype 3/4 HEV cause sporadic disease in India, a disease-endemic area, we determined HEV genotype in a group of patients with such disease. Methods: A part of the HEV open reading frame (ORF) 1 was amplified and sequenced from sera of 74 patients with sporadic acute viral hepatitis E from four cities in India. The sequences were compared with prototype sequences for various HEV genotypes and subgenotypes and analyzed using phylogenetic tools to determine the genotype of the isolates. For 12 specimens, a part of HEV ORF2 was also similarly analyzed. Results: Partial ORF1 sequences of all the 74 isolates belonged to genotype 1 HEV, with 88.2% to 100% nucleotide identity with the prototype genotype 1 isolates. Partial ORF2 sequences for all the 12 isolates also belonged to genotype 1 HEV. On phylogenetic analysis, 71 isolates clustered with prototype genotype 1a HEV; the remaining three isolates were located between subgenotypes 1a and 1c but were closer to the former. Conclusion: Human sporadic acute hepatitis E in India is caused almost exclusively by genotype 1 HEV. © 2018, Indian Society of Gastroenterology.
An epitope-imprinted piezoelectric diagnostic tool for Neisseria meningitidis detection
(John Wiley and Sons Ltd, 2016) Neha Gupta; Kavita Shah; Meenakshi Singh
Neisseria meningitidis, a human-specific bacterial pathogen causes bacterial meningitis by invading the meninges (outer lining) of central nervous system. It is the polysaccharide present on the bacterial capsid that distinguishes various serogroups of N. meningitidis and can be utilized as antigens to elicit immune response. A computational approach identified candidate T-cell epitopes from outer membrane proteins Por B of N. meningitidis (MC58): (273KGLVDDADI282 in loop VII and 170GRHNSESYH179 in loop IV) present on the exposed surface of immunogenic loops of class 3 outer membrane proteins allele of N. meningitidis. One of them, KGLVDDADI is used here for designing a diagnostic tool via molecularly imprinted piezoelectric sensor (molecularly imprinted polymer-quartz crystal microbalance) for N. meningitidis strain MC58. Methacrylic acid, ethylene glycol dimethacrylate and azoisobutyronitrile were used as functional monomer, cross-linker and initiator, respectively. The epitope can be simultaneously bound to methacrylic acid and fitted into the shape-selective cavities. On extraction of epitope sequence from thus grafted polymeric film, shape-selective and sensitive sites were generated on electrochemical quartz crystal microbalance crystal, ie, known as epitope imprinted polymers. Imprinting was characterized by atomic force microscopy images. The epitope-imprinted sensor was able to selectively bind N. meningitidis proteins present in blood serum of patients suffering from brain fever. Thus, fabricated sensor can be used as a diagnostic tool for meningitis disease. Copyright © 2016 John Wiley & Sons, Ltd.
Artificial intelligence and machine learning disciplines with the potential to improve the nanotoxicology and nanomedicine fields: a comprehensive review
(Springer Science and Business Media Deutschland GmbH, 2023) Ajay Vikram Singh; Mansi Varma; Peter Laux; Sunil Choudhary; Ashok Kumar Datusalia; Neha Gupta; Andreas Luch; Anusha Gandhi; Pranav Kulkarni; Banashree Nath
The use of nanomaterials in medicine depends largely on nanotoxicological evaluation in order to ensure safe application on living organisms. Artificial intelligence (AI) and machine learning (MI) can be used to analyze and interpret large amounts of data in the field of toxicology, such as data from toxicological databases and high-content image-based screening data. Physiologically based pharmacokinetic (PBPK) models and nano-quantitative structure–activity relationship (QSAR) models can be used to predict the behavior and toxic effects of nanomaterials, respectively. PBPK and Nano-QSAR are prominent ML tool for harmful event analysis that is used to understand the mechanisms by which chemical compounds can cause toxic effects, while toxicogenomics is the study of the genetic basis of toxic responses in living organisms. Despite the potential of these methods, there are still many challenges and uncertainties that need to be addressed in the field. In this review, we provide an overview of artificial intelligence (AI) and machine learning (ML) techniques in nanomedicine and nanotoxicology to better understand the potential toxic effects of these materials at the nanoscale. © 2023, The Author(s).
Comparative study of simple and modified rice husk biochar for cadmium removal: Adsorption performance and possible mechanisms
(IWA Publishing, 2023) Kaushik Gautam; Neha Gupta; Devendra Kumar Patel; Rajeev Pratap Singh; Anita Singh
In the present study, the simple and chemically modified forms of biochar (KMnO4 and HNO3; 0.01 M) obtained from rice husks were used to study the possible mechanism behind the process of cadmium (Cd) adsorption from the synthetic solution having Cd2þ ranged from 10 to 50 ppm. At 50 ppm, the maximum adsorption has been observed and it showed 93% removal by the KMnO4 modification and 86% by HNO3 modification, whereas simple biochar led to 82% removal only. The adsorption pattern follows the Langmuir and pseudo-second-order model. With characterization techniques, it has been confirmed that the KMnO4-modified forms of biochar showed more adsorption capacity than HNO3-modified and simple biochar. Furthermore, to check its practical applicability, the modified forms of biochar have been applied to the wastewater collected from Banaras locomotive works, Bhagwanpur, and Lohta sites of Varanasi city, UP, India. Again, the maximum adsorption of Cd2þ has been observed with KMnO4 modification (92-95%) at all the sites. This result also confirmed that KMnO4 was the best modifying agent over HNO3. Therefore, its application could be promoted in metal-contaminated water and soil to decrease the availability of toxic metals. © 2023 The Author.
Comparison of intravaginal and interstitial brachytherapy in cervical cancer after inadvertent hysterectomy: a retrospective study
(Nature Research, 2025) Sunil Choudhary; Ankita Pandey; Ankita Singh; Ankur Mourya; Neha Gupta; Syed Mohamed Shajid; Gogul Priean Venkatachalam; Sangita Rai; Sakshi Agarwal; P. Venkatraman; Lalit Mohan Mohan Aggarwal
The purpose of this study was to compare intravaginal brachytherapy (IVBT) with interstitial brachytherapy (ISBT) in patients presenting with residual or recurrent disease after inadvertent hysterectomy for cervical cancer. Records of consecutive patients with cervical cancer, registered in the Radiotherapy Outpatient Department (RTOPD) between March 2018 and March 2021, who had inadvertent hysterectomy followed by external beam radiotherapy (EBRT) and IVBT (n = 15) or ISBT (n = 15) were analyzed retrospectively. All the patients received a dose of 45–50 Gy/25 fractions in 5 weeks by EBRT with concurrent cisplatin. A dose of 6 Gy/fraction/week for two consecutive weeks was prescribed at 5 mm from the surface of the vaginal cylinder in the IVBT arm. Patients in the ISBT arm were treated with 6 Gy/fraction for four fractions over two days with Martinez Universal Perineal Interstitial Template (MUPIT). Overall survival (OS) and disease-free survival (DFS) were the primary endpoints. Acute and late toxicities were the secondary endpoints. Median follow-up (FU) was 24.3 months and 32.8 months in the IVBT and ISBT arms respectively. Most of the patients failed within 12–18 months after brachytherapy. The 3-year OS for IVBT and ISBT arms were 54% and 93% respectively (p = 0.011). The 3-year DFS for IVBT and ISBT arms were 42% and 93% respectively(p = 0.023). Both the arms had similar acute & late toxicities. ISBT had significantly better survival outcomes in terms of OS, and DFS with similar toxicity as compared to IVBT in patients with residual or recurrent disease after inadvertent hysterectomy for cervical cancer. © The Author(s) 2025.
Comparison of two hypofractionated radiotherapy schedules in locally advanced postmastectomy breast cancer patients
(Wolters Kluwer Medknow Publications, 2020) Sunil Choudhary; Neha Gupta; Shagun Misra; Narvada Narain Munnee; Amit Kumar; Rakesh Ranjan; Sovan Sarang Dhar; Deepak Kumar; Ankur Mourya; Lalit Mohan Aggarwal
Introduction: The role of hypofractionated radiotherapy (HFRT) in postmastectomy breast cancer patients is not well established. This study was done to establish the role of two different HFRT schedules in the treatment of chest wall and regional lymph nodes after mastectomy. Materials and Methods: Between 2012 and 2016, consecutively registered patients of locally advanced breast cancer patients having undergone mastectomy and adjuvant radiotherapy (RT) at a tertiary cancer center were analyzed. Locoregional recurrence (LRR) was the primary endpoint, whereas overall survival (OS), disease-free survival (DFS), and both acute and late adverse events were secondary endpoints. Results: A total of 34 patients who were treated with 39 Gy in 13 fractions over 2½ weeks and 35 patients who were treated with 40 Gy in 15 fractions over 3 weeks were identified. The median follow-up period was 47 months and 63.5 months in the 39 Gy and 40 Gy arms, respectively. LRR was seen in 11.8% and 8.6% of patients in the 39 Gy and 40 Gy arms, respectively. OS at 4 years was 66% and 71.5% in the 39 Gy and 40 Gy arms, respectively. The mean DFS for 39 Gy and 40 Gy arms was 43.6 months and 66.4 months, respectively (P = 0.822). Acute skin toxicity was similar in the two groups. Arm edema was significantly more in the 40 Gy arm. Conclusion: The two HFRT schedules are equivalent to each other in terms of survival outcomes. Arm edema is higher with 40 Gy arm as compared to 39 Gy arm. © 2020 Journal of Cancer Research and Therapeutics | Published by Wolters Kluwer - Medknow.
Cyanobacteria: a key player in nutrient cycling
(Elsevier, 2023) Alka Bhardwaj; Prashansa Singh; Neha Gupta; Samujjal Bhattacharjee; Ankit Srivastava; Anirbana Parida; Arun Kumar Mishra
Cyanobacteria are photosynthetic prokaryotic organisms that are found in various aquatic and terrestrial environments. They are one of the oldest and most primitive forms of life on Earth, playing critical role in the biological nutrient cycling of different habitats. The phenomenon of nutrient cycling delineates the continual recycling of essential elements, which are rendered accessible to the biota of an ecosystem. Cyanobacteria possess the ability to fixate atmospheric nitrogen and transform it into a bioavailable form, which can be utilized by other organisms in the ecosystem. This process is called nitrogen fixation, and it helps to increase the availability of nitrogen in the ecosystem, which is an essential nutrient for the growth of different life forms. They also play a key role in carbon cycling by capturing carbon dioxide through photosynthesis and releasing oxygen into the atmosphere. Indeed, cyanobacteria played a significant role in making the early environment aerobic by producing oxygen through photosynthesis. This process helps to regulate the amount of carbon dioxide in the atmosphere, which is important for mitigating the effects of climate change. Additionally, cyanobacteria can contribute to the cycling of other nutrients, such as phosphorus and sulfur, by releasing them from organic matter and making them available for other organisms to use. Overall, cyanobacteria are crucial for the cycling of different nutrients, including nitrogen, carbon, phosphorus, and sulfur, and their impact on the health of the ecosystem cannot be overstated. The presence of these microorganisms is essential for ensuring a stable and thriving environment, and their involvement in nutrient cycling and oxygenic photosynthesis has constituted a critical component in the evolutionary history of life on Earth. © 2024 Elsevier Inc. All rights reserved.
Cyanophages: interacting mechanism and evolutionary significance
(Elsevier, 2023) Ankit Srivastava; Neha Gupta; Arun Kumar Mishra
Cyanophages are viruses that exhibit a highly specific interaction mechanism with their host cyanobacteria. This specificity is driven by the recognition of host cell surface receptors by the phage tail fibers, which allows for the injection of the phage DNA into the host cell. Once inside the host cell, the phage DNA is replicated and transcribed, leading to the production of new phage particles. The evolutionary significance of cyanophages is multifaceted that lies in their role in shaping microbial communities and biogeochemical cycles in aquatic ecosystems. On one hand, cyanophages act as important regulators of cyanobacterial populations in aquatic ecosystems. These viruses have been shown to impact the growth, abundance, and diversity of cyanobacteria, which in turn can affect the functioning of the ecosystem as a whole. On the other hand, the study of cyanophages also provides insight into the coevolution of viruses and their hosts. The transfer of genetic material between cyanophages and cyanobacteria can occur through a variety of mechanisms, including lysogeny, transduction, and horizontal gene transfer. Understanding the mechanisms and evolutionary dynamics of virus–host interactions is therefore crucial for predicting the response of aquatic ecosystems to changing environmental conditions. Therefore cyanophages provide a window into the complex relationships between viruses and their hosts, and the important role of viruses in shaping aquatic ecosystems. Overall, this chapter presents valuable insights into the complex relationships between viruses and cyanobacteria, and the important role of viruses in shaping microbial communities and aquatic ecosystems. © 2024 Elsevier Inc. All rights reserved.
Development of highly sensitive and selective sensor for ethionamide guided by molecular modelling via electropolymerized molecularly imprinted films
(Elsevier Inc., 2020) Archana Kushwaha; Neha Gupta; Juhi Srivastava; Ambareesh Kumar Singh; Meenakshi Singh
Here, a selective sensing technology for the drug ethionamide used to treat multi-drug resistant tuberculosis is developed based on molecular imprinting. The molecular imprinting matrix is developed strategically by molecular modelling via density functional theory. 3-Thiophene acetic acid was predicted as suitable functional monomer for imprinting ethionamide. Polymeric film was formed on the surface of glassy carbon electrode by electropolymerization of 3-thiophene acetic acid in presence of ethionamide as template by cyclic voltammetry. The obtained sensor was highly selective towards analyte ethionamide and the recognition was quantified by differential pulse voltammetric experiments of ethionamide molecule. A highly selective (imprinting factor: 8.92) and sensitive (limit of detection: 0.005 µg/mL) molecularly imprinted sensor with good reproducible behaviour (R2 = 0.9882, RSD 2.68%) was fabricated. © 2019 Elsevier B.V.
Dose at posterior-inferior border of symphysis point: A predictor for vaginal stricture in cervical cancer
(Elsevier Inc., 2023) Ankita Singh; Nilesh Mani; Lalit M. Aggarwal; Sumit Agarwal; Ankur Mourya; Ashish Verma; Antara Bagchi; Neha Gupta; Sunil Choudhary
PURPOSE: To study the effect of various dose-volume parameters on the severity of vaginal stricture (VS) and the correlation of the latter with the posterior-inferior border of symphysis (PIBS) points in locally advanced cervical cancer patients treated with concurrent chemoradiation and brachytherapy. METHODS AND MATERIALS: A prospective study was done on 45 histologically proven locally advanced cervical cancer patients between January 2020 and March 2021. All of them were treated with concurrent chemoradiation with 6 MV photon linear accelerator to a dose of 45 Gy/25 fractions in 5 weeks. Twenty-three patients were treated with intracavitary brachytherapy with a dose of 7 Gy/fraction/week for three fractions. Twenty-two patients were treated with interstitial brachytherapy, with 6 Gy/fraction for four fractions, each fraction 6 h apart. Grading of VS was done as per Common Terminology Criteria for Adverse Events version 5. RESULTS: The median followup was 21.5 months. About 37.8% of patients had VS with a median duration of 8.0 months (4.0–12 months). About 22.2% had Grade 1, 6.7% had Grade 2, and 8.9% had Grade 3 toxicity. Doses at PIBS and PIBS−2 points had no correlation with vaginal toxicity, however, the dose at PIBS+2 was significantly associated with VS (p = 0.004). The treated length of the vagina at the time of brachytherapy (p = 0.001), initial tumor volume (p = 0.009), and vaginal involvement after completion of external beam radiotherapy (EBRT) (p = 0.01) were also statistically significant with the development of VS of Grade 2 or more. CONCLUSIONS: Dose at PIBS + 2, treated length of the vagina with brachytherapy, initial tumor volume, and post-EBRT vaginal involvement are strong predictors for the severity of VS. © 2023 American Brachytherapy Society
Efficient biodegradation of sodium dodecyl sulfate (SDS) by the cyanobacterium Fischerella sp. lmga1 harbouring SdsA1 hydrolase
(Springer Science and Business Media B.V., 2023) Samujjal Bhattacharjee; Ankit Srivastava; Anirbana Parida; Neha Gupta; Prashansha Singh; Satya Shila Singh; Arun Kumar Mishra
Sodium dodecyl sulfate (SDS) accumulation in nature impart detrimental effects on various lifeforms as it truncates cellular proteins. The present study exhibited SDS bioremediation ability of cyanobacterium Fischerella sp. lmga1. Phylogeny across cyanobacterial phyla depicted uneven distribution and abundance of SdsA1 hydrolase (characterised for SDS hydrolysis in Pseudomonas aeruginosa PA01) in Microcystis spp. and Fischerella spp. Further, Fischerella sp. lmga1, was administered with 200 µM SDS to validate not only the bioremediation capability but also the physiological adjustments during SDS hydrolysis. The preliminary effect of SDS was harsh, as the cyanobacterial growth was significantly reduced along with subsequent decline in photopigment, chlorophyll a fluorescence and carbohydrate. Nevertheless, drastic rejuvenation upon 8th day of treatment and increment in photosynthetic capacity suggested the resilience of lmga1 against SDS. Further, about 50% removal of SDS with highest degradation rate was observed on 10th day of treatment, followed after substantial increment in the expression of sdsA1 on 8th day. Interestingly, the Fourier-transform infrared (FTIR) depicted homeostasis in the carbon allocation pattern or membrane lipid dynamics during SDS removal, indicating the endurance of lmga1. Although, the peak intensity at 1077 cm−1 reduced on day 4 corresponded to DNA damage, yet increased peak intensity on 8th day ascertained damage repair. Molecular docking of SdsA1 hydrolase of Fischeralla thermalis CCME 5301 with SDS depicted low binding energy of -4.3 kCal mol−1, thereby endorsing stable binding. Thus, this study corroborated the application of lmga1 for removal of surfactant as it displayed commendable resilience and SDS removal capability. Graphical abstract: [Figure not available: see fulltext.] © 2023, The Author(s), under exclusive licence to Springer Nature B.V.
Epithelial-myoepithelial carcinoma at the base of the tongue presented with metastatic disease in the absence of myoepithelial anaplasia
(Wolters Kluwer Medknow Publications, 2020) Mahima Yadav; Neha Gupta; Richa Katiyar; Shashikant C. U. Patne
Epithelial-myoepithelial carcinoma (EMC) is a biphasic low-grade malignant tumor that shows ductal structures lined by the ductal cells with surrounding myoepithelial cells. EMC is most commonly reported in the parotid gland followed by other major and minor salivary glands. EMC of the tongue is an extremely uncommon tumor, with only five previously published case reports. We herein report the sixth case of EMC of the tongue. A 40-year-old female who had throat pain, dysphagia, and right earache for 3 years showed a 4 cm × 4 cm nodular tumor at the base of her tongue. Histopathological and immunohistochemical features were diagnostic of EMC with cervical lymph node metastasis. The metastatic behavior of EMC of the tongue in the absence of myoepithelial anaplasia or high-grade histological features is unusual and reported in this case report for the first time. © 2020 Journal of Cancer Research and Therapeutics | Published by Wolters Kluwer - Medknow.
Epitope imprinting of iron binding protein of Neisseria meningitidis bacteria through multiple monomers imprinting approach
(John Wiley and Sons Ltd, 2018) Neha Gupta; Roop Shikha Singh; Kavita Shah; Rajniti Prasad; Meenakshi Singh
Epitope imprinting is a promising technique for fabrication of novel diagnostic tools. In this study, an epitope imprinted methodology for recognition of target epitope sequence as well as targeted protein infused by bacterial infection in blood samples of patients suffering from brain fever is developed. Template sequence chosen is a ferric iron binding fbp A protein present in Neisseria meningitidis bacteria. To orient the imprinting template peptide sequence on gold surface of electrochemical quartz crystal microbalance (EQCM), thiol chemistry was utilized to form the self-assembled monolayer on EQCM electrode. Here, synergistic effects induced by various noncovalent interactions extended by multiple monomers (3-sulfopropyl methacrylate potassium-salt and benzyl methacrylate) were used in fabricating the imprinting polymeric matrix with additional firmness provided by N,N-methylene-bis-acrylamide as cross-linker and azo-isobutyronitrile as initiator. Extraction of template molecule was carried out with phosphate buffer solution. After extraction of epitope molecules from the polymeric film, epitope molecularly imprinted polymeric films were fabricated on EQCM electrode surface. Nonimprinted polymers were also synthesized in the similar manner without epitope molecule. Detection limit of epitope molecularly imprinted polymers and imprinting factor (epitope molecularly imprinted polymers/nonimprinted polymers) was calculated 1.39 ng mL−1 and 12.27 respectively showing high binding capacity and specific recognition behavior toward template molecule. Simplicity of present method would put forward a fast, facile, cost-effective diagnostic tool for mass health care. Copyright © 2018 John Wiley & Sons, Ltd.
GA trained parallel hidden layered ANN based differential protection of three phase power transformer
(Elsevier Ltd, 2015) Harish Balaga; Neha Gupta; Devendra Nath Vishwakarma
Transformer protection is an established area of research to find the fastest and efficient differential relay algorithm that isolates the transformer from remaining system causing least damage. Algorithm should also avoid mal-operation when differentiating between the operating conditions. Various differential algorithms were proposed in the past, allowing a scope for further research. In this paper, ANN is used as a pattern classifier which discriminates among normal, magnetizing inrush, over-excitation and internal fault currents in a power transformer. The proposed scheme has been realized through different ANN architectures including a new customized parallel-hidden layered design, which originates to be more accurate in differentiating between the normal wave and faulty wave despite the shape similarity. A combination of two ANNs in Master-Slave mode has also been discussed. Back Propagation (BP) and Genetic Algorithm (GA) are used to train the multi-layered feed forward neural network and their simulated results are compared. The neural network trained by GA gives more accurate results (in terms of mean square error) than by BP Algorithm. Simulated data are used as an input to the ANN to verify the accuracy of the algorithm. Thus, GA trained Master-Slave ANN based differential protection scheme provides faster, accurate, more secured and dependable relay for power transformers. © 2014 Elsevier Ltd. All rights reserved.
HBsAg Level as Predictor of Liver Fibrosis in HBeAg Positive Patients With Chronic Hepatitis B Virus Infection
(Elsevier B.V., 2015) Sundeep K. Goyal; Ashok K. Jain; Vinod K. Dixit; Suneet K. Shukla; Mohan Kumar; Jayant Ghosh; Arttrika Ranjan; Neha Gupta; Manish Tripathi
Background and aims: Preliminary data suggests lower serum hepatitis B surface antigen level is associated with more severe liver fibrosis in HBeAg positive patients. We evaluated the association of HBsAg level with biochemical, virological, and histological features in asymptomatic patients with chronic HBV infection. Methods: HBsAg levels were measured at baseline in 481 asymptomatic, treatment naive patients with chronic HBV infection. Subjects were followed-up prospectively (median, 12; range, 8-36 months). Phases of HBV infection were defined after regular monitoring of HBV-DNA and transaminases. Liver histology was scored using the METAVIR system. Results: HBeAg positive (n, 126) patients were significantly younger than HBeAg negative (n, 355), median age 26 vs 30 years; P<0.01. HBV genotype could be determined in 350 patients, 240 (68.57%) had genotype D and 100 (28.57%) had genotype A. HBsAg level had modest correlation with serum HBV DNA(r = 0.6 vs 0.4 in eAg positive & negative respectively). HBeAg+ve patients with fibrosis score≥F2 showed significantly lower median serum HBsAg levels and serum HBV DNA levels compared with patients with F0-F1 score (median, range; 4.51, 2.99-6.10 vs 5.06, 4.13-5.89, P<0.01) and (8.39, 3.85-10.60, P<0.01) respectively. Significant inverse correlation of HBsAg level was found with liver fibrosis in eAg positive group (r = -0.76; P<0.001). HBsAg level cut off value 4.7log10IU/ml predicted moderate to advance fibrosis (F≥2) with 92% sensitivity, 85% specificity & 91% negative predictive value. Conclusion: Lower HBsAg level might reflect the status of advanced liver fibrosis in HBeAg positive chronic hepatitis B subjects. © 2015 INASL.
Highly sensitive and selective estimation of aspartame by chitosan nanoparticles–graphene nanocomposite tailored EQCM-MIP sensor
(Springer Verlag, 2019) Juhi Srivastava; Neha Gupta; Archana Kushwaha; Seema Umrao; Anchal Srivastava; Meenakshi Singh
Here, a molecularly imprinted electrochemical quartz crystal microbalance (MIP-EQCM) sensor for aspartame is developed by grafting the aspartame-imprinted polymeric matrix of chitosan on gold-coated quartz crystal electrode. Chitosan nanoparticles being biocompatible, biodegradable and also having large surface area provide a better platform by forming a well-dispersed composite suspension with graphene. Additionally graphene facilitates direct electron transfer to electrode surface for electrochemical study because of having enhanced electrical conductivity. This EQCM-MIP sensor was characterized by atomic force microscopy, contact angle measurements, cyclic voltammetry and differential pulse voltammetry (DPV). The obtained MIP showed high affinity to aspartame. A reliable method for analysis of aspartame in real and commercial samples was achieved by coupling EQCM-MIP with DPV. Linear relationship with R2 = 0.9749 (EQCM) and R2 = 0.9760 (DPV) on binding of aspartame at various concentrations was observed. Detection limit of 0.45 µg mL−1 (EQCM) and 0.07 µg mL−1 (DPV) of the fabricated sensor shows that high sensitivity and high selectivity among various structural analogues of aspartame were also achieved. The improved detection limit is promising for determination of trace amount of aspartame. This demonstrates good memory capacity of this EQCM sensor. High recovery percentage and applicability of EQCM-MIP sensor in real matrices and commercial samples offers good potential for various applications. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
Influence of adjuvant therapy on pattern of failure and survival in curatively resected gallbladder carcinoma
(Wolters Kluwer Medknow Publications, 2021) Sunil Choudhary; Neha Gupta; Chandra Prakash Verma; Avipsa Das; Lalit Mohan Aggarwal; Mallika Tewari; Abhijit Mandal; Anupam Kumar Asthana
Purpose: The study was done to evaluate the role of adjuvant therapy in curatively resected Stage II and III gallbladder carcinoma (GBC). Materials and Methods: This was a retrospective analysis of patients of GBC registered between 2008 and 2017 in outpatient department of a tertiary cancer hospital in India. Patients who had any of the following adjuvant treatment after radical surgery: (a) external beam radiotherapy (RT) alone, (b) chemotherapy (CT) alone, and (c) RT with CT (CRT) were considered for the study. Results: A total of fifty patients could meet the selection criteria. It was seen that seven patients were treated with RT, 20 with CT, and 23 with CRT. Median follow-up for patients who were alive was 26.7 months. Nineteen patients had locoregional failure while eight had distant failure. Patients treated with CRT had a significantly better mean overall survival compared to those treated with RT or CT (44.0 months, 12.5 months, and 15.1 months, respectively; P = 0.003). Similarly, mean disease-free survival was superior in CRT arm compared to RT and CT arms (43.6 months, 9.6 months, and 12.4 months, respectively; P = 0.002). Conclusions: Adjuvant CRT had better survival outcome compared to patients treated with either RT or CT with Stage II and III disease after curative cholecystectomy. © 2020 Journal of Cancer Research and Therapeutics.
Iterative analysis of metabolic modulation in the cyanobacterium Aphanizomenon flos-aquae 2012 KM1/D3 upon nitric oxide synthase derived NO induction
(Elsevier B.V., 2022) Neha Gupta; Arun Kumar Mishra
Nitric oxide synthase (NOS) in mammals is recognized for its essentialities in several metabolism including blood vascular relaxation and nerves transmission etc. yet their functionalities in prokaryotes are largely unknown. Our study aimed to evaluate the putative role of nitric oxide synthase (NOS) derived nitric oxide (NO) during oxidative burst in the cyanobacterium, Aphanizomenon flos-aquae 2012/KM1/D3. Here, the accumulation of NO was dramatically reduced upon NOS inhibitor L-NG-Nitro arginine methyl ester (L-NAME) supplementation, exhibiting significant NO synthesis by NOS, whereas addition of L-arginine increase NOS derived NO in a dose dependent manner. Moreover, the reduction in the growth and metabolic activities of the cyanobacterium were evident upon L-NAME treatment that possibly pertained to decline in photopigments, PSII efficiency, loss in membrane integrity and DNA damage due to oxidative burst which culminated into cell death. Besides, the increment in carbohydrates and lipid content ensued with a decrease in protein content, indicating gluconeogenesis. Additionally, NOS inhibition disrupted the fatty acid and hydrocarbon profile, suggesting diminished membrane fluidity and cell integrity. However, higher content of flavonoids, phenolics, thiols and proline in L-NAME treated cells was also observed. Furthermore, L-arginine supplementation enhanced pigment content, photosynthetic efficiency, and reduced oxidative stress, thereby enhancing cyanobacterial growth. Further, L-arginine supplementation maintained Asc/DHAsc and GSH/GSSG ratio, conferred redox homeostasis. These results suggest that the NOS activity plays a critical role in protecting cyanobacteria from oxidative burst, maintaining their physiological balance. © 2022 Elsevier B.V.