Browsing by Author "Navin Kumar"

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Ameliorative mechanisms of polyamines against abiotic stress in the rice plants
(Elsevier, 2018) Navin Kumar; Shekhar Mallick
Rice (Oryza sativa L.) is a staple food crop for about two thirds of the worlds’ population. Under stress conditions, the level of polyamines (PAs) biosynthesis in rice plants elevates. The ubiquitous PAs are involved in the regulation of plant development, physiological processes, and tolerance against diverse abiotic stresses. The two enzymes, viz. ornithine decarboxylase (ODC) and arginine decarboxylase (ADC), initiate the synthesis of PAs. From the PA, putrescine (Put), enzymatic synthesis of another two PAs that is, spermine (Spm) and spermidine (Spd) by Spm synthase and Spd synthase takes place. In rice plants, ADC mediated synthesis of Put, Spm, and Spd plays a crucial role in the amelioration of abiotic stress rather than the activity of ODC. The role of PAs in rice plants against drought stress, osmotic stress, and heat stress have been reported. The elevated level of PAs (Put, Spm, and Spd) is attributed to the ability of plants to counter stress by binding with the negative charged biomolecules that is, nucleic acids, proteins, and phospholipids in order to stabilize their structures under diverse abiotic stress conditions. The role of Spd and Put has been ascribed to heat tolerance through modulation of glutathione/GSSG, and fatty acid synthesis in order to recover from lipid peroxidation under oxidative stress in rice plants, respectively. The roles of PAs and the detailed mechanism of association with other metabolic pathways such as shikimate, phosphoenol pyruvate, Asada-Halliwell cycle, and nitrogen assimilation remains to be understood in detail. © 2019 Elsevier Inc. All rights reserved.
GABA accretion reduces Lsi-1 and Lsi-2 gene expressions and modulates physiological responses in Oryza sativa to provide tolerance towards arsenic
(Nature Publishing Group, 2017) Navin Kumar; Arvind Kumar Dubey; Atul Kumar Upadhyay; Ambedkar Gautam; Ruma Ranjan; Saripella Srikishna; Nayan Sahu; Soumit Kumar Behera; Shekhar Mallick
GABA counteracts wide range of stresses through regulation of GABA shunt pathway in plants. Although, GABA assisted tolerance against As toxicity in plants is still unexplored. We have examined GABA induced tolerance in rice seedlings with two exposure periods of GABA i.e., short term and long term. Results showed that accumulation of GABA reduced the expressions of Lsi-1 and Lsi-2 transporter genes, which ultimately decreased the accumulation of As in rice seedlings. The accumulation of GABA also modulated the gene expression of GABA shunt pathway and activity of antioxidant enzymes, which strongly induced the tolerance in plants. Antioxidant enzymes such as CAT, POD, GPX and SOD showed maximum alteration in activity with GABA accretion. In both exposure periods, long term accumulation of GABA was highly efficient to provide tolerance to plants against As(III), while higher level of GABA at short term was toxic. Tolerance responses of GABA towards As(III) was reflected by minimal changes in various physiological (WUE, A, gs, PhiPS2, qp, NPQ, ETR and Trmmol) and growth parameters with concomitant accumulation. Oxidative stress marker such as TBARS and H2O2 contents were reduced with GABA accumulation. These results suggested that GABA sturdily inhibits As accumulation and provides tolerance towards As(III). © 2017 The Author(s).
GABA mediated reduction of arsenite toxicity in rice seedling through modulation of fatty acids, stress responsive amino acids and polyamines biosynthesis
(Academic Press, 2019) Navin Kumar; Ambedkar Gautam; Arvind Kumar Dubey; Ruma Ranjan; Ashutosh Pandey; Babita Kumari; Gayatri Singh; Sachin Mandotra; Puneet Singh Chauhan; Saripella Srikrishna; Venkatesh Dutta; Shekhar Mallick
γ-aminobutyric acid (GABA) is a free amino acid, which helps to counteract biotic and abiotic stresses in plants. In the present study, two concentrations of GABA, i.e., 0.5 mM and 1 mM were applied to examine the tolerance of rice seedlings against As(III) (25 µM) toxicity, through the modulations of fatty acids (FAs), stress responsive amino acids (AAs) and polyamines (PAs) biosynthesis. Exogenous GABA (0.5 mM) application significantly reduced the H 2 O 2 and TBARS levels and recovered the growth parameters against As(III) stressed rice seedlings. Simultaneously, co-application of GABA (0.5 and 1 mM) and As(III), consistently enhanced the level of unsaturated fatty acids (USFA) (cis-10-pentadecanoic acid, oleic acid, α-linolenic acid and γ-linolenic acid), which was higher than saturated fatty acid (SFA). Among the USFAs, level of linolenic acid was found to be always higher with GABA application. Similarly, elevated level of AAs (proline, methionine, glutamic acid and cysteine) was also observed with the application of GABA (0.5 and 1 mM) in As(III) stressed seedlings. GABA also enhanced the expression of genes involved in the polyamine synthesis pathway namely arginine decarboxylase (AD), spermine (SPM) and spermidine (SPD) synthase against As(III) treatments, which was higher in roots than in shoots, resulting in enhanced root PAs level. Contrarily, the expression of S-adenosylmethionine decarboxylase (S-AMD) was significantly higher in shoots. Among all the PAs, level of putrescine (PUT) was found to be highest with GABA application. Overall, the study demonstrates that GABA (0.5 mM) at lower concentration plays a vital role in As(III) tolerance by enhancing the biosynthesis of USFA, AA and PA, reducing the level of TBARS and H 2 O 2 in rice seedlings. © 2019 Elsevier Inc.
Head injury pattern in fatal road traffic accidents
(World Informations Syndicate, 2016) D.P. Singh; Navin Kumar; Mayank Gupta; Manoj Kumar
This study was conducted in mortuary of the Department of Forensic Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi where 100 fatal Road Traffic Injury cases over a period of three years from 2012-2015. Pattern of distribution of head injury cases in fatal road traffic accidents were analyzed in detail during post mortem. In skeletal fractures overall fractures of whole calvaria + facial skeleton were the commonest, followed by temporo-parietal fractures. Subdural hemorrhage was the most common affliction of meninges. © 2016, World Informations Syndicate. All rights reserved.
Knowledge and health seeking behavior related to Kala-Azar in rural communities of East Champaran District, Bihar
(Innovare Academics Sciences Pvt. Ltd, 2017) Navin Kumar; T.B. Singh; L.P. Meena
Objective: To find out the sociodemographic characteristics, knowledge and health seeking behavior related to KA in the East Champaran district, Bihar among study subject. Methods: A case-control study was conducted to understand the knowledge and health seeking behavior related to KA in the East Champaran district. A total of 100 KA cases and 100 healthy controls selected from the neighborhoods of cases. Results: The knowledge of the population showed that the male constituted 58% of the total population in which 56% were case and 60% were control. Majority of the respondent 76.5% were aware from the KA. Maximum of the respondent 72.5% believed that biting time of sand flies were in the night. Moreover, 71% respondent cannot know how to protect the KA transmission. Conclusion: These results will be useful for further improvement in the KA control programs for intervention strategies. The knowledge of the study subject about KA, the vectors, the transmission of KA, and control measures was poor which needs some effort of the public health system by the Ministry working in the field of health. © 2017 The Authors.
Polyamines metabolism and NO signaling in plants
(Elsevier, 2021) Navin Kumar; Ambedkar Gautam; Arvind Kumar Dubey
Nitrogenous compounds such as amino acids (AAs), polyamines (PAs), and nitric oxide (NO) plays a crucial role in the plant development, growth, and signaling. Among these compounds, PAs are ubiquitous polycationic compounds, which are usually found in all living organisms, including bacteria to plants. Multifunctional PAs mainly interact with the biomolecules such as DNA or protein to strengthen the structure. However, NO is a gaseous signaling molecule, regulates several physiological functions in the plants. In recent studies, PAs found to be induce the biosynthesis of NO, but the exact mechanism remains to be deciphered. In plants, PAs and NO crosstalk regulates the different biological functions such as stress responses and hormone regulations. In light of recent findings, PAs and NO crosstalk have been an emerging topic for researchers. Overall, the nitrogen metabolism and its related compounds are a remarkable research topic, which may be biotechnologically important to develop a high-yielding and stress-resistant crops. © 2022 Elsevier Inc.
Reducing Arsenic Uptake in Cereal Crop Plants with Sugarcane Waste Application: A Comparative Study on the Effects on Physiology, Biochemistry, and Grain Nutrient Status
(Springer, 2023) Ambedkar Gautam; Nikita Basant; Navin Kumar; Kriti; Shiv Naresh Singh; Arvind Kumar Dubey; Gayatri Singh; Babita Kumari; Kavita Shah; Shekhar Mallick
C3 (Oryza sativa L.) and C4 (Zea mays L.) plants differ both in their carbon fixing mechanism, and thus, their responses toward stresses also differ. Owing to the mutually competitive nature of uptake between phosphate (iP) and arsenate (AsV) in plants, and given that the level of sucrose is also influenced by iP, interplay of their uptake mechanisms eventually results in reducing the AsV uptakes. The present study intends to comparatively assess the reduction in AsIII and AsV uptake and its toxicity between Oryza sativa L. and Zea mays L. when cultivated with sucrose-containing sugarcane wastes (SWs; bagasse, molasses, and pressmud) conducted under a simulated outdoor pot experiment. Overall improvement in growth, physiological performance, stress, and antioxidant response was exhibited in both the plants with SWs application. The SWs application also improved soil physiochemical parameters viz, pH, EC, OC, OM, and micronutrients. Application of SW also reduced the iAs accumulation in grains of both rice (50–87%) and maize (70–96%), along with enhancement in Fe (142%, and 122%, respectively), and Zn (132% and 131%, respectively). Most of the 17 grain’s amino acids (AAs) increased in maize against iAs stress, whereas Ser decreased in both, and Ile and Gly additionally in rice. Essential AAs viz. Phe, Thr, and Met are influenced negatively by iAs, whereas nonessential AAs viz. Cys, Ser, Pro, Gly in both the plant grains are positively influenced by iP and negatively by OC. Thus, the application of SWs containing residual sucrose > 9.5 µM g−1, through a fertilizer formulation or by direct soil amendments in iAs-contaminated soil can be an agronomic practice to reduce the iP fertilization and limit the iAs contamination in the food-chain. © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Sucrose plays key role in amelioration of arsenic induced phytotoxicity through modulating phosphate and silicon transporters, physiological and biochemical responses in C3 (Oryza sativa L.) and C4 (Zea mays L.)
(Elsevier B.V., 2020) Ambedkar Gautam; Navin Kumar; Arvind Kumar Dubey; Ruma Ranjan; Nayan Sahu; Soumit Kumar Behera; Kavita Shah; Rudra Deo Tripathi; Shekhar Mallick
Sucrose is a precursor for several vital biomolecules and essential for growth of the plant. The present study investigated the interrelationship between sucrose (25 μM) and PO4 (iP) in amelioration of arsenic (iAs) [60 μM of AsIII and AsV] toxicity in C3 (Oryza sativa) and C4 (Zea mays) plants. Application of sucrose recovered the iAs induced phytotoxicity, morphological and physiological parameters in both C3 and C4 plant seedlings. Alternatively, iAs accumulation enhanced the endogenous level of sucrose in the seedlings. Also, sucrose suppressed the gene expression of low silicon transporters in both C3 and C4 plants, resulting in lower iAs uptake. Presence of iP, suppressed expression of root iP transporters which coincided with reduced iAs accumulation in maize root (23 %) over its AsIII, and that in shoots of both of C3 (12 %) and C4 (35 %) seedlings over AsV. However, the iP transporters in rice [OsPT-1, 6 & 9] and in maize (ZmPHT1;6, ZmPHT2;1, ZmPHT1;1), shoot and root, respectively, were upregulated with sucrose application, enhancing the iP accumulation. Sucrose application reduced the level of H2O2 and TBARS in both plants, while enhanced the thiolic compounds (GSH, cysteine and NPSH) and activities of antioxidant enzymes (APX, GPX and SOD) against iAs toxicity under both available and iP deprived conditions. The physiological parameters such as A, PhiPS2, gs and qP recovered whereas, NPQ was reduced with sucrose application, towards iAs treatments in both the seedlings. Overall, the results indicate that sucrose plays a vital role in the amelioration of iAs induced toxicity through modulation of iP and low silicon transporters, resulting in reducing the iAs accumulation, physiological parameters and antioxidants. © 2019 Elsevier B.V.
The Psychology of the Bhagavad Gita: Understanding the Dynamics of Suffering and ealing
(Routledge, 2024) Navin Kumar; Oorvi Bhateja; Ajai Pratap Singh
Suffering and healing are both ends of a continuum known as life, with a human being standing in the middle. The actions we choose and the route we follow determine where we will go; whether we will heal and succeed in our lives or suffer as a result of our actions. This research seeks to investigate how the Bhagavad Gita differs from the Gospels in addressing the reality of suffering and transformational healing methods. The narrative analysis approach of qualitative research is used in this study to investigate and identify themes and subthemes that describe the notions of suffering and healing. This research delves deeply and specifically into how the Bhagavad Gita understands suffering and healing. The discussion section of this study also provides specific highlights from several chapters of the Bhagavad Gita that, when applied to human lives, might help enlighten the way to healing. © 2024 Taylor & Francis Group, LLC.
The Psychology of the Bhagavad Gita: Understanding the Dynamics of Suffering and Healing
(Routledge, 2025) Navin Kumar; Oorvi Bhateja; Ajai Pratap Singh
Suffering and healing are both ends of a continuum known as life, with a human being standing in the middle. The actions we choose and the route we follow determine where we will go; whether we will heal and succeed in our lives or suffer as a result of our actions. This research seeks to investigate how the Bhagavad Gita differs from the Gospels in addressing the reality of suffering and transformational healing methods. The narrative analysis approach of qualitative research is used in this study to investigate and identify themes and subthemes that describe the notions of suffering and healing. This research delves deeply and specifically into how the Bhagavad Gita understands suffering and healing. The discussion section of this study also provides specific highlights from several chapters of the Bhagavad Gita that, when applied to human lives, might help enlighten the way to healing. © 2024 Taylor & Francis Group, LLC.
Trend of unnatural deaths in male population in varanasi region-A retrospective study
(World Informations Syndicate, 2016) Mayank Gupta; Navin Kumar; Manoj Kumar Pathak; Awdhesh Kumar
Death may be natural (resulting from disease) or unnatural deliberate action of other (homicide), intentionally self inflected (suicide), result of an environmental influence (accident). Deaths in males due to unnatural causes, especially in the 2nd and 3rd decades of their life, have been observed in Indian society for the last few decades. Present study is carried out at forensic medicine department, Institute of Medical Sciences, Banaras Hindu University, Varanasi. Relevant information and subjective data like age, habitat, and manner of death of various causes of death victims have been collected from medico legal autopsy register. Data of 3711 autopsied males are analyzed retrospective for periods of two and half years from January 2012 to July 2014 The aim of this study is to find out the pattern of unnatural deaths in male and the various factors associated with such deaths in Varanasi region and to out find remedial measures to bring down the incidence. Road traffic accidents 1504(40.53%) contribute most common cause and 21 to 40 year found to be the most common age group affected 1709(46.05%). Male residing in rural area 2911(78.44%) and religion Hindu 3008(81.06%) were way more affected. Such unnatural death can be prevented by education, awareness, change in attitude and mindset of society etc. but the law enforcement agencies must also take strict measures to curb it down. © 2016, World Informations Syndicate. All rights reserved.