Browsing by Author "Ashish Singh"

Now showing 1 - 7 of 7

Cypermethrin alters the status of oxidative stress in the peripheral blood: relevance to Parkinsonism
(Kluwer Academic Publishers, 2014) Pratibha Tripathi; Ashish Singh; Sonal Agrawal; Om Prakash; Mahendra Pratap Singh
Parkinson’s disease (PD) is a motor scarcity disorder characterized by the striatal dopamine deficiency owing to the selective degeneration of the nigrostriatal dopaminergic neurons. While oxidative stress is implicated in PD, prolonged exposure to moderate dose of cypermethrin induces Parkinsonism. The study aimed to investigate the status of oxidative stress indicators and antioxidant defence system of the polymorphonuclear leukocytes (PMNs), platelets and plasma to delineate the effect of Parkinsonian dose of cypermethrin in the peripheral blood of rats and its subsequent relevance to Parkinsonism. Nitrite content, lipid peroxidation (LPO) and activity of superoxide dismutase (SOD), catalase, glutathione reductase (GR) and glutathione-S-transferase (GST) were measured in the PMNs, platelets and plasma of control and cypermethrin-treated rats in the presence or absence of a microglial activation inhibitor, minocycline or a dopamine precursor containing the peripheral 3,4-dihydroxyphenylalanine decarboxylase inhibitor, named syndopa, employing the standard procedures. The striatal dopamine was measured to assess the degree of neurodegeneration/neuroprotection. Cypermethrin increased nitrite and LPO in the plasma, platelets and PMNs while it reduced the striatal dopamine content. Catalase and GST activity were increased in the PMNs and platelets; however, it was reduced in the plasma. Conversely, SOD and GR activities were reduced in the PMNs and platelets but increased in the plasma. Minocycline or syndopa reduced the cypermethrin-mediated changes towards normalcy. The results demonstrate that cypermethrin alters the status of oxidative stress indicators and impairs antioxidant defence system of the peripheral blood, which could be effectively salvaged by minocycline or syndopa. The results could be of value for predicting the nigrostriatal toxicity relevant to Parkinsonism. © 2014, University of Navarra.
Ibuprofen abates cypermethrin-induced expression of pro-inflammatory mediators and mitogen-activated protein kinases and averts the nigrostriatal dopaminergic neurodegeneration
(Humana Press Inc., 2016) Ashish Singh; Pratibha Tripathi; Om Prakash; Mahendra Pratap Singh
Cypermethrin induces oxidative stress, microglial activation, inflammation and apoptosis leading to Parkinsonism in rats. While ibuprofen, a non-steroidal anti-inflammatory drug, relieves from inflammation, its efficacy against cypermethrin-induced Parkinsonism has not yet been investigated. The study aimed to explore the protective role of ibuprofen in cypermethrin-induced Parkinsonism, an environmentally relevant model of Parkinson’s disease (PD), along with its underlying mechanism. Animals were treated with/without cypermethrin in the presence/absence of ibuprofen. Behavioural, immunohistochemical and biochemical parameters of Parkinsonism and expression of pro-inflammatory and pro-apoptotic proteins along with mitogen-activated protein kinases (MAPKs) were determined. Ibuprofen resisted cypermethrin-induced behavioural impairments, striatal dopamine depletion, oxidative stress in the nigrostriatal tissues and loss of the nigral dopamine producing cells and increase in microglial activation along with atypical expression of pro-inflammatory and apoptotic proteins that include cyclooxygenase-2, tumour necrosis factor-α, MAPKs (c-Jun N-terminal kinase, p38 and extracellular signal-regulated kinase), B cell lymphoma 2-associated protein X, tumour suppressor protein p53, cytochrome c and caspase-3 in the nigrostriatal tissue. The results obtained thus demonstrate that ibuprofen lessens inflammation and regulates MAPKs expression thereby averts cypermethrin-induced Parkinsonism. © 2015, Springer Science+Business Media New York.
IL-4 Haplotype -590T, -34T and Intron-3 VNTR R2 Is Associated with Reduced Malaria Risk among Ancestral Indian Tribal Populations
(2012) Aditya Nath Jha; Vipin Kumar Singh; Namrata Kumari; Ashish Singh; Justin Antony; Hoang van Tong; Sakshi Singh; Sudhanshu S. Pati; Pradeep K. Patra; Rajender Singh; Nguyen L. Toan; Le H. Song; Amal Assaf; Iara J. T. Messias-Reason; Thirumalaisamy P. Velavan; Lalji Singh; Kumarasamy Thangaraj
Background: Interleukin 4 (IL-4) is an anti-inflammatory cytokine, which regulates balance between TH1 and TH2 immune response, immunoglobulin class switching and humoral immunity. Polymorphisms in this gene have been reported to affect the risk of infectious and autoimmune diseases. Methods: We have analyzed three regulatory IL-4 polymorphisms; -590C>T, -34C>T and 70 bp intron-3 VNTR, in 4216 individuals; including: (1) 430 ethnically matched case-control groups (173 severe malaria, 101 mild malaria and 156 asymptomatic); (2) 3452 individuals from 76 linguistically and geographically distinct endogamous populations of India, and (3) 334 individuals with different ancestry from outside India (84 Brazilian, 104 Syrian, and 146 Vietnamese). Results: The -590T, 34T and intron-3 VNTR R2 alleles were found to be associated with reduced malaria risk (P<0.001 for -590C>T and -34C>T, and P = 0.003 for VNTR). These three alleles were in strong LD (r2>0.75) and the TTR2 (-590T, -34T and intron-3 VNTR R2) haplotype appeared to be a susceptibility factor for malaria (P = 0.009, OR = 0.552, 95% CI = 0.356 -0.854). Allele and genotype frequencies differ significantly between caste, nomadic, tribe and ancestral tribal populations (ATP). The distribution of protective haplotype TTR2 was found to be significant (χ23 = 182.95, p-value <0.001), which is highest in ATP (40.5%); intermediate in tribes (33%); and lowest in caste (17.8%) and nomadic (21.6%). Conclusions: Our study suggests that the IL-4 polymorphisms regulate host susceptibility to malaria and disease progression. TTR2 haplotype, which gives protection against malaria, is high among ATPs. Since they inhabited in isolation and mainly practice hunter-gatherer lifestyles and exposed to various parasites, IL-4 TTR2 haplotype might be under positive selection. © 2012 Jha et al.
Rodent models and contemporary molecular techniques: Notable feats yet incomplete explanations of Parkinson's disease pathogenesis
(Humana Press Inc., 2012) Sharawan Yadav; Anubhuti Dixit; Sonal Agrawal; Ashish Singh; Garima Srivastava; Anand Kumar Singh; Pramod Kumar Srivastava; Om Prakash; Mahendra Pratap Singh
Rodent models and molecular tools, mainly omics and RNA interference, have been rigorously used to decode the intangible etiology and pathogenesis of Parkinson's disease (PD). Although convention of contemporary molecular techniques and multiple rodent models paved imperative leads in deciphering the role of putative causative factors and sequential events leading to PD, complete and clear-cut mechanisms of pathogenesis are still hard to pin down. The current article reviews the implications and pros and cons of rodent models and molecular tools in understanding the molecular and cellular bases of PD pathogenesis based on the existing literature. Probable rationales for short of comprehensive leads and future possibilities in spite of the extensive applications of molecular tools and rodent models have also been discussed. © Springer Science+Business Media, LLC 2012.
Standardization and classification of in vitro biofilm formation by clinical isolates of Staphylococcus aureus
(Medknow Publications, 2017) Ashish Singh; Pradyot Prakash; Arvind Achra; Gyan Singh; Arghya Das; Rakesh Singh
Background: Staphylococcus aureus is Gram-positive bacterium commonly associated with nosocomial infections. The development of biofilm exhibiting drug resistance especially in foreign body associated infections has enabled the bacterium to draw considerable attention. However, till date, consensus guidelines for in vitro biofilm quantitation and categorization criterion for the bacterial isolates based on biofilm-forming capacity are lacking. Therefore, it was intended to standardize in vitro biofilm formation by clinical isolates of S. aureus and then to classify them on the basis of their biofilm-forming capacity. Materials and Methods: A study was conducted for biofilm quantitation by tissue culture plate (TCP) assay employing 61 strains of S. aureus isolated from clinical samples during May 2015- December 2015 wherein several factors influencing the biofilm formation were optimized. Therefore, it was intended to propose a biofilm classification criteria based on the standard deviation multiples of the control differentiating them into non, low, medium, and high biofilm formers. Results: Brain-heart infusion broth was found to be more effective in biofilm formation compared to trypticase soy broth. Heat fixation was more effective than chemical fixation. Although, individually, glucose, sucrose, and sodium chloride (NaCl) had no significant effect on biofilm formation, a statistically significant increase in absorbance was observed after using the supplement mix consisting of 222.2 mM glucose, 116.9 mM sucrose, and 1000 mM NaCl (P = 0.037). Conclusions: The present study puts forth a standardized in vitro TCP assay for biofilm biomass quantitation and categorization criteria for clinical isolates of S. aureus based on their biofilm-forming capacity. The proposed in vitro technique may be further evaluated for its usefulness in the management of persistent infections caused by the bacterium. © 2017 Journal of Global Infectious Diseases | Published by Wolters Kluwer - Medknow.
The association of ABO blood group with the asymptomatic COVID-19 cases in India
(Elsevier Ltd, 2021) Prajjval Pratap Singh; Abhishek K. Srivastava; Sudhir K. Upadhyay; Ashish Singh; Shashank Upadhyay; Pradeep Kumar; Vandana Rai; Pankaj Shrivastava; Gyaneshwer Chaubey
The COVID-19 pandemic resulted in multiple waves of infection worldwide. The large variations in case fatality rate among different geographical regions suggest that the human susceptibility against this virus varies substantially. Several studies from different parts of the world showed a significant association of ABO blood group and COVID-19 susceptibility. It was demonstrated that individuals with blood group O are at the lower risk of coronavirus infection. To establish the association of ABO blood group in SARS-CoV-2 susceptibility, we for the first time analysed SARS-CoV-2 neutralising antibodies among 509 individuals, collected from three major districts of Eastern Uttar Pradesh region of India. Interestingly, we found neutralising antibodies in a significantly higher percentage of people with blood group AB (0.36) followed by B (0.31), A (0.22) and lowest in people with blood group O (0.11). We further estimated that people with blood group AB are at comparatively higher risk of infection than other blood groups. Thus, among the asymptomatic SARS-CoV-2 recovered people blood group AB has highest, whilst individuals with blood group O has lowest risk of infection. © 2021 Elsevier Ltd
The Phylogeography of Y-Chromosome Haplogroup H1a1a-M82 Reveals the Likely Indian Origin of the European Romani Populations
(2012) Niraj Rai; Gyaneshwer Chaubey; Rakesh Tamang; Ajai Kumar Pathak; Vipin Kumar Singh; Monika Karmin; Manvendra Singh; Deepa Selvi Rani; Sharath Anugula; Brijesh Kumar Yadav; Ashish Singh; Ramkumar Srinivasagan; Anita Yadav; Manju Kashyap; Sapna Narvariya; Alla G. Reddy; George van Driem; Peter A. Underhill; Richard Villems; Toomas Kivisild; Lalji Singh; Kumarasamy Thangaraj
Linguistic and genetic studies on Roma populations inhabited in Europe have unequivocally traced these populations to the Indian subcontinent. However, the exact parental population group and time of the out-of-India dispersal have remained disputed. In the absence of archaeological records and with only scanty historical documentation of the Roma, comparative linguistic studies were the first to identify their Indian origin. Recently, molecular studies on the basis of disease-causing mutations and haploid DNA markers (i.e. mtDNA and Y-chromosome) supported the linguistic view. The presence of Indian-specific Y-chromosome haplogroup H1a1a-M82 and mtDNA haplogroups M5a1, M18 and M35b among Roma has corroborated that their South Asian origins and later admixture with Near Eastern and European populations. However, previous studies have left unanswered questions about the exact parental population groups in South Asia. Here we present a detailed phylogeographical study of Y-chromosomal haplogroup H1a1a-M82 in a data set of more than 10,000 global samples to discern a more precise ancestral source of European Romani populations. The phylogeographical patterns and diversity estimates indicate an early origin of this haplogroup in the Indian subcontinent and its further expansion to other regions. Tellingly, the short tandem repeat (STR) based network of H1a1a-M82 lineages displayed the closest connection of Romani haplotypes with the traditional scheduled caste and scheduled tribe population groups of northwestern India. © 2012 Rai et al.