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      • Oxidative Stress and Antioxidants in Disease and Cancer: A Review

        Gupta, Rakesh Kumar,Patel, Amit Kumar,Shah, Niranjan,Choudhary, Arun Kumar,Jha, Uday Kant,Yadav, Uday Chandra,Gupta, Pavan Kumar,Pakuwal, Uttam Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

        Reactive oxygen species (ROS), highly reactive molecules, are produced by living organisms as a result of normal cellular metabolism and environmental factors, and can damage nucleic acids and proteins, thereby altering their functions. The human body has several mechanisms to counteract oxidative stress by producing antioxidants. A shift in the balance between oxidants and antioxidants in favor of oxidants is termed as "oxidative stress". Paradoxically, there is a large body of research demonstrating the general effect of oxidative stress on signaling pathways, less is known about the initial and direct regulation of signaling molecules by ROS, or what we term the "oxidative interface." This review focuses on the molecular mechanisms through which ROS directly interact with critical signaling molecules to initiate signaling in a broad variety of cellular processes, such as proliferation and survival (MAP kinases and PI3 kinase), ROS homeostasis, and antioxidant gene regulation (Ref-1 and Nrf-2). This review also deals with classification as well as mechanisms of formation of free radicals, examining their beneficial and deleterious effects on cellular activities and focusing on the potential role of antioxidants in preventing and repairing damage caused by oxidative stress. A discussion of the role of phytochemical antioxidants in oxidative stress, disease and the epigenome is included.

      • Do the Health Claims Made for Morinda citrifolia (Noni) Harmonize with Current Scientific Knowledge and Evaluation of its Biological Effects

        Gupta, Rakesh Kumar,Patel, Amit Kumar Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.8

        Morinda citrifolia, also known as Great Morinda, Indian Mulberry, or Noni, is a plant belonging to the family Rubiaceae. A number of major chemical compounds have been identified in the leaves, roots, and fruits of the Noni plant. The fruit juice is in high demand in alternative medicine for different kinds for illnesses such as arthritis, diabetes, high blood pressure, muscle ached and pains, menstrual difficulties, headache, heart diseases, AIDS, gastric ulcer, sprains, mental depression, senility, poor digestion, arteriosclerosis, blood vessel problems, and drug addiction. Several studies have also demonstrated anti-inflammatory, antioxidant and apoptosis-inducing effects of Noni in various cancers. Based on a toxicological assessment, Noni juice was considered as safe. Though a large number of in vitro, and, to a certain extent, in vivo studies demonstrated a range of potentially beneficial effects, clinical data are essentially lacking. To what extent the findings from experimental pharmacological studies are of potential clinical relevance is not clear at present and this question needs to be explored in detail before an recommendations can be made.

      • KCI등재

        Thermokinetics behavior of epoxy adhesive reinforced with low viscous aliphatic reactive diluent and nano-fillers

        Amit Kumar Singh,Bishnu Prasad Panda,Smita Mohanty,Sanjay Kumar Nayak,Manoj Kumar Gupta 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.11

        The current study reports the effect of low viscous aliphatic reactive diluent (RD), MWCNT and VGCF on the curing kinetics of amine cured epoxy adhesive system employing non-isothermal differential scanning calorimetric (DSC) technique. Non-isothermal DSC thermograms of epoxy adhesive were studied at various heating rates: 5, 10 and 15 oC/min. The decrease in the exothermic peak height with the introduction of MWCNTs and VGCFs was taken as proof of the acceleration effect of nano-fillers on the epoxy-amine curing reaction. Also, increased Tonset, TP and ΔHcurs values were observed for epoxy/RD adhesive system at all heating rates. The value of activation energy (Ea) was determined using Kissinger and Flynn-Wall-Ozawa methods. Experimental results showed that the addition of 10 wt% RD increased the Ea from 60 to 63 kJ/mol on account of the reduced viscosity, allowing better contact of resin with the curing agent. Furthermore, MWCNTs have an accelerating effect on the cure kinetics that does not change the autocatalytic cure reaction mechanism of epoxy resin. It was also found that the addition of MWCNT and VGCF decreases the overall degree of conversion, as evident with lower ΔHcure and Ea of the cured adhesive when compared with epoxy/RD system. The dependency of Ea on degree of conversion ranging from α =0.1 to 0.9was also investigated. The two normalized functions y(α) and z(α) were also considered in order to study the complex curing mechanism. The kinetic parameters m, n and lnA were obtained by using two parameter autocatalytic Sestak-Berggren model. The curves revealed good agreement between experimentally determined and theoretically obtained MWCNT/VGCF reinforced epoxy adhesive systems.

      • Interactions between Oxidative Stress, Lipid Profile and Antioxidants in Breast Cancer: A Case Control Study

        Gupta, Rakesh Kumar,Patel, Amit Kumar,Kumari, Rajni,Chugh, Seema,Shrivastav, Chitrangada,Mehra, Siddharth,Sharma, Ajay Narayan Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

        Oxidant/antioxidant balance has been suggested as an important factor for initiation and progression of cancer. The objective of this study was to determine changes in the levels of malondialdehyde (MDA), nitric oxide (NO), total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, total antioxidant capacity (TAC), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) activities in serum samples of breast cancer patients (n=30) and healthy subjects (n=100). MDA and NO levels were found to be increased in breast cancer patients compared to the healthy subject group (p<0.05). Total cholesterol and triglycerides were elevated; and HDL-cholesterol level was found to be decreased in the cancer patients as compared to the healthy subjects (p<0.05). Compared to the healthy group, both serum TAC levels (p<0.001) and activity of SOD and GSH-Px (p=0.05) were found to be decreased in the breast cancer patients as compared to the healthy controls. Considering the data presented in this study, we suggest that free radicals induce lipid eroxidation and peroxidation of unsaturated fatty acid with decreased activity of enzymatic antioxidants in breast cancer.

      • KCI등재

        Predictive Breast Cancer Statistical Modelling for Early Diagnosis

        Amit Kumar Gupta,Ankit Verma,Vipin Kumar,Nikhil Kumar,Dowon Kim,Young-Jin Jung,Mangal Sain 한국자기학회 2023 Journal of Magnetics Vol.28 No.4

        Breast cancer is a significant global health concern, stressing the urgent need for early detection. Early diagnosis improves access to varied treatments and significantly enhances patient outcomes. This study explores breast cancer detection over two days, aiming to create a precise and efficient machine learning model. The research uses a diverse dataset, combining clinical, genetic, and imaging data, including magnetic resonance imaging (MRI), X-ray, and electromagnetic data. Rigorous data preprocessing, including variable normalization and feature identification, enhances dataset quality. Predictive models use statistical techniques like logistic regression, decision trees, and random forest. Key metrics, such as accuracy, precision, recall, and area under the curve (AUC), assess model efficacy. Results reveal high accuracy and AUC scores, indicating potential for precise breast cancer detection. The study enhances our understanding of breast cancer dynamics, showcasing the effectiveness of machine learning for accurate and efficient early diagnosis. The research underscores diverse datasets and careful statistical modeling as crucial for predictive breast cancer capabilities.

      • KCI등재

        Advances in Floating Aerogenerators: Present Status and Future

        Amit Kumar Mondal,Surajit Mondal,Vindhya Devalla,Paawan Sharma,Mukul Kumar Gupta 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.11

        High altitude winds are considered to be the most favorable source of renewable energy in the future. In this paper, review has been conducted on harnessing of high altitude wind energy via floating type aero-generators. This new generation of systems employs tethered wings, aircrafts, multi-copters, balloons in order to harness the higher atmospheric winds. A number of systems based on different concepts have been analyzed and tested from mid-seventies, with a rapid acceleration in last couple of years. This paper presents a comprehensive overview of different technologies that have been designed/ built to harvest the energy of high altitude winds, highlighting the accomplished results, technological issues and classification of such systems have been proposed on the basis of their working and design. Apart from the Airborne Wind Energy or High-Altitude Wind Energy based systems, a brief overview on offshore floating wind turbines have also been provided.

      • KCI등재

        Current updates in acute traumatic aortic injury: radiologic diagnosis and management

        Shivani Gupta,Atin Kumar,Tejinder Kaur,Shivanand Gamanagatti,Abhinav Kumar,Amit Gupta,Subodh Kumar 대한응급의학회 2022 Clinical and Experimental Emergency Medicine Vol.9 No.2

        Acute traumatic aortic injuries, which have substantial lethal outcomes at the time of admission, are fatal in 80% to 90% of cases. These injuries are relatively rare and have nonspecific clinical presentations. Radiologists and emergency physicians need to identify the radiological signs of acute traumatic aortic injury and differentiate them from common imaging errors to ensure accurate diagnosis and determine appropriate management protocols. In combination with image-guided interventions, advances in cross-sectional imaging have enabled nonsurgical management of acute traumatic aortic injuries. Timely and precise diagnoses of these injuries following prompt treatment are essential as up to 90% of patients presenting at the hospital can undergo early repair.

      • KCI등재

        Clinical spectrum of elderly-onset inflammatory bowel disease in India

        Yogesh Kumar Gupta,Arshdeep Singh,Vikram Narang,Vandana Midha,Ramit Mahajan,Varun Mehta,Dharmatma Singh,Namita Bansal,Madeline Vithya Barnaba Durairaj,Amit Kumar Dutta,Ajit Sood 대한장연구학회 2023 Intestinal Research Vol.21 No.2

        Background/Aims: Inflammatory bowel disease (IBD) is increasingly being recognized in elderly patients. Data on clinical spectrum of elderly-onset IBD patients is lacking from India. Methods: A cross-sectional retrospective analysis of a prospectively maintained database of patients diagnosed with IBD was conducted at 2 centers in India. The clinical spectrum of elderly-onset IBD including demographic profile (age and sex), clinical presentation, disease characteristics (disease behavior and severity, extent of disease), and treatment were recorded and compared with adult-onset IBD. Results: During the study period, 3,922 (3,172 ulcerative colitis [UC] and 750 Crohn’s disease [CD]) patients with IBD were recorded in the database. A total of 186 patients (4.74%; 116 males [62.36%]) had elderly-onset IBD (69.35% UC and 30.64% CD). Diarrhea, blood in stools, nocturnal frequency and pain abdomen were the commonest presentations for UC, whereas pain abdomen, weight loss and diarrhea were the most frequent symptoms in CD. For both elderly onset UC and CD, majority of the patients had moderately severe disease. Left-sided colitis was the commonest disease location in UC. Isolated ileal disease and inflammatory behavior were the most common disease location and behavior, respectively in CD. 5-Aminosalicylates were the commonest prescribed drug for both elderly onset UC and CD. Thiopurines and biologics were used infrequently. Prevalence of colorectal cancer was higher in elderly onset IBD. Conclusions: Elderly onset IBD is not uncommon in India. Both the elderly onset UC and CD were milder, with no significant differences in disease characteristics (disease extent, location and behavior) when compared to adult-onset IBD. Colorectal cancer was more common in elderly onset IBD.

      • SCIESCOPUSKCI등재

        Kinetics of In-situ Degradation of Nerve Agent Simulants and Sarin on Carbon with and without Impregnants

        Saxena, Amit,Sharma, Abha,Singh, Beer,Suryanarayana, Malladi Venkata Satya,Mahato, Timir Haran,Sharma, Mamta,Semwal, Rajendra Prasad,Gupta, Arvind Kumar,Sekhar, Krishnamurthy Korean Carbon Society 2005 Carbon Letters Vol.6 No.3

        Room temperature kinetics of degradation of nerve agent simulants and sarin, an actual nerve agent at the surface of different carbon based adsorbent materials such as active carbon grade 80 CTC, modified whetlerite containing 2.0 and 4.0 % NaOH, active carbon with 4.0 % NaOH, active carbon with 10.0 % Cu (II) ethylenediamine and active carbon with 10.0 % Cu (II) 1,1,1,5,5,5-hexafluoroacetylacetonate were studied. The used adsorbent materials were characterized for surface area and micropore volume by $N_2$ BET. For degradation studies solution of simulants of nerve agent such as dimethyl methylphosphonate (DMMP), diethyl chlorophosphate (DEClP), diethyl cyanophosphate (DECnP) and nerve agent, i.e., sarin in chloroform were prepared and used for the uniform adsorption on the adsorbent systems using their incipient volume at room temperature. Degradation kinetics was monitored by GC/FID and was found to be following pseudo first order reaction. Kinetics parameters such as rate constant and half life were calculated. Half life of degradation with modified whetlerite (MWh/NaOH) system having 4.0 % NaOH was found to be 1.5, 7.9, 1206 and 20 minutes for DECnP, DEClP, DMMP and sarin respectively. MWh/NaOH system showed maximum degradation of simulants of nerve agents and sarin to their hydrolysis products. The reaction products were characterized using NMR technique. MWh/NaOH adsorbent was also found to be active against sulphur mustard.

      • KCI등재후보

        Impregnated Active Carbon-Shelf Life Studies and Its Evaluation Against Cyanogen Chloride with and without Canister

        Beer Singh,Amit Saxena,Avanish Kumar Srivastava,Devendra Kumar Dubey,Arvind Kumar Gupta 한국탄소학회 2007 Carbon Letters Vol.8 No.4

        Samples of active carbon of 1150 m2/g surface area were impregnated with ammoniacal salts of copper, chromium and silver, with and without triethylenediamine. The samples of impregnated carbon were aged at 50℃, with and without 90% RH (relative humidity), for a little more than one year and chemically evaluated periodically. Initially copper (II) and chromium (VI) reduced very fast in the samples in humid atmosphere to the extent of 30% and 60% respectively in four months. These values were found to be unaffected by the presence of triethylenediamine (TEDA) indicating that the chemical did not retard the reduction process of chromium (VI) and copper (II). However, in the absence of humidity the reduction of the impregnants was significantly less (10-12%, w/w) in four months. It was quite evident; therefore, that the moisture was mainly responsible for the reduction of chromium (VI) and copper (II) species in impregnated carbons. The prolonged ageing of the samples with and without triethylenediamme after four months with and without humid atmosphere showed that the extent of reduction of chromium (VI) was very low, i.e. 5-10% and of copper (II) was 2-25%. Silver is not reduced due to carbon, as it remained unchanged in concentration on storage. The impregnated carbon samples (100 g) without triethylenediamine, which were aged at room temperature for 5 years in absence of humidity and unaged when evaluated against cyanogen chloride (CNCl) at a concentration of 4 mg/L and airflow rate of 30 lpm showed a high degree of protection (80- 110 minutes).

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