Publications by authors named "Suresh Gahlawat"

6 Publications

  • Page 1 of 1

Real-time monitoring of air pollutants in seven cities of North India during crop residue burning and their relationship with meteorology and transboundary movement of air.

Sci Total Environ 2019 Nov 15;690:717-729. Epub 2019 Jun 15.

Indian Institute of Tropical Meteorology, Pashan, Pune, India. Electronic address:

Air pollutants emissions due to the burning of crop residues could adversely affect human health, environment, and climate. Hence, a multicity campaign was conducted during crop residue burning period in Indo Gangetic Plains (IGP) to study the impact on ambient air quality. Seventeen air pollutants along with five meteorological parameters, were measured using state of the art continuous air quality monitors. The average concentration of PM, PM and PM during the whole campaign were 196.7±30.6, 148.2±20, and 51.2±8.9 μgm and daily average concentration were found several times higher than national ambient air quality standards for 24h. Amritsar had the highest average concentration of PM (178.4±83.8 μgm) followed by Rohtak and Sonipat (158.4±79.8, 156.5±105.3μgm), whereas Chandigarh recorded the lowest concentration (112.3±6.9μgm). The concentration of gaseous pollutants NO, NO, NO and SO were also observed highest at Amritsar location, i.e., 6.6±2.6ppb, 6.2±0.7ppb, 12.7±3.0ppb, and 7.5±3.3ppb respectively. The highest average O and CO were 22.5±19.3ppb and 1.5±1.2ppm during the campaign. The level of gaseous pollutants and Volatile organic compounds (VOCs) found to be elevated during the campaign, which can play an important role in the formation of secondary air pollutants. The correlation of meteorology and air pollutants was also studied, and O shows a significant relation with temperature and UV (R=0.87 and 0.74) whereas VOCs shows a significant correlation with temperature (R=-0.21 to -0.47). Air quality data was also analyzed to identify sources of emissions using principal component analysis, and it identifies biomass burning and vehicular activities as major sources of air pollution.
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http://dx.doi.org/10.1016/j.scitotenv.2019.06.216DOI Listing
November 2019

Emergence of sulfadoxine-pyrimethamine resistance in Indian isolates of Plasmodium falciparum in the last two decades.

Infect Genet Evol 2015 Dec 28;36:190-198. Epub 2015 Aug 28.

National Institute of Malaria Research, Sector-8 Dwarka, New Delhi 110077, India. Electronic address:

Genotyping the sulfadoxine-pyrimethamine (SP) genes will help in identifying the genes under drug selection and the emergence of resistance in dhfr and dhps genes. India is an important hotspot for studying malaria due to the immense climatic diversity prevalent in the country. The central and eastern parts of the country are most vulnerable sites where malaria cases are reported throughout the year. From different regions of the country 173 field isolates were genotyped at various loci in dhfr and dhps genes collected between 1994 and 2013. This encompasses the period before antimalarial resistance emerged and the period after the use of combination therapy was made mandatory in the country. We observed the rise of resistant SP alleles from very low frequencies (in the year 1994) to steadily rising (in the year 2000) and maintaining this increasing trend subsequently (in the year 2013) as shown by the sequence analysis of dhfr and dhps genes. This study assessed the prevalence of mutations in dhfr and dhps genes associated with SP resistance in samples indicative of increase in resistance levels of Plasmodium falciparum to SP even after the change in malaria treatment policy in the country.
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http://dx.doi.org/10.1016/j.meegid.2015.08.027DOI Listing
December 2015

Sequence and topological characterization of Toll-like receptor 8 gene of Indian riverine buffalo (Bubalus bubalis).

Trop Anim Health Prod 2013 Jan 24;45(1):91-9. Epub 2012 May 24.

National Bureau of Animal Genetic Resources, GT Road By-Pass, Karnal, 132 001, Haryana, India.

In this study, buffalo (Bubalus bubalis) Toll-like receptor 8 (TLR8) gene has been characterized by sequence analysis and detecting polymorphism. Complete ORF of buffalo TLR8 gene was amplified using the RNA isolated from spleen tissue, which was found to be 3,102 nucleotides long encoding a 1,033 amino acid protein. Buffalo TLR8 had 10 nucleotide changes as compared to other livestock species resulting in six unique amino acid changes, four of them lying within leucine-rich repeat (LRR) domains. As compared to cattle (Bos indicus and Bos taurus), out of fifteen cysteine residues, fourteen were conserved and Cys at position 521 was replaced by Arg. Nine of the LRR domains had no amino acid change as compared to cattle, whereas LRR-C-terminus had maximum, five amino acid changes. Sequence characterization of 12 riverine and swamp buffaloes revealed presence of four polymorphic nucleotides, two of them were non-synonymous, one synonymous and one site in 3'UTR. PCR-RFLP genotyping of non-synonymous SNP 2758A>G (ILeu920Val) in Toll-interleukin-1 receptor domain of 463 swamp and riverine buffaloes showed a higher frequency of allele A in swamp (95 %) as compared to riverine (9.84 %) buffaloes.
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http://dx.doi.org/10.1007/s11250-012-0178-1DOI Listing
January 2013

Development of an in vitro system to measure the sensitivity to the antiviral Mx protein of fish viruses.

J Virol Methods 2012 Jun 1;182(1-2):1-8. Epub 2012 Mar 1.

Marine Scotland, Marine Laboratory, Aberdeen AB11 9DB, United Kingdom.

Mx is a structural protein, induced by type I interferon (IFN), with direct antiviral properties. In fish the inherent contribution of Mx protein to viral protection is unknown. The transgenic Chinook salmon embryonic (CHSE)-TOF cell line was genetically modified to express the rainbow trout Mx (rbtMx1) protein under the control of the tetracycline derivative, doxycycline (DOX). Two clones CHSE-TOF-MX8 and CHSE-TOF-MX10 were isolated and characterised by qPCR. The level of resistance to Infectious Pancreatic Necrosis Virus (IPNV), Salmon Alphavirus (SAV), Infectious Haematopoietic Necrosis Virus (IHNV) and Epizootic Haematopoietic Necrosis Virus (EHNV) of the CHSE-TOF, CHSE-TOF-MX8 and CHSE-TOF-MX10 cell lines cultivated with and without DOX was measured. A novel method was established to measure accurately the level of sensitivity of any given viral isolate to Mx protein. IPNV and SAV viruses were highly sensitive to the presence of rbtMx1 in the cells whereas IHNV and EHNV showed partial resistance suggesting contrasting viral evasion strategies between these categories of viruses.
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http://dx.doi.org/10.1016/j.jviromet.2012.01.014DOI Listing
June 2012

Expression of interferon and interferon--induced genes in Atlantic salmon Salmo salar cell lines SHK-1 and TO following infection with Salmon AlphaVirus SAV.

Fish Shellfish Immunol 2009 Apr 3;26(4):672-5. Epub 2009 Mar 3.

Fisheries Research Services, FRS Marine Laboratory, Aberdeen, Scotland, UK.

Salmon AlphaVirus (SAV) is the aetiological agent of Salmon Pancreas Disease (SPD), a serious disease in farmed Atlantic salmon. Currently there is no available information on the ability of this virus to stimulate or suppress aspects of innate immunity in host cells. Two different Atlantic salmon cell lines (SHK-1 and TO), both derived from head kidney leucocytes, were infected with SAV and the kinetics and magnitude of gene expression were studied by real-time quantitative PCR. SAV nsP1 gene transcripts for strain P42P increased rapidly in TO cells with subsequent development of a cytopathic effect (CPE) while this virus strain hardly replicated at all SHK-1 cells causing no CPE. SAV P42P induced strong expression of type I IFN (IFN) and the antiviral IFN-induced gene MX transcripts in SHK-1 cells. Although the IFN response in infected TO cells was higher than in SHK-1 cells, the level of MX transcripts was lower. This may be because the virus was able to interfere with IFN-signaling and suppress MX transcription or that the TO cells are less able to transcribe the MX gene. Either way, it may account for why the SHK-1 cells suppress SAV replication while the TO cells are highly susceptible and succumb to the virus. The present results provide the first evidence for differential induction of expression of the interferon-induced antiviral gene, MX, correlating with resistant (SHK-1) and susceptible (TO) Atlantic salmon cell lines in response to infection by SAV.
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http://dx.doi.org/10.1016/j.fsi.2009.02.021DOI Listing
April 2009

Infectious pancreatic necrosis virus suppresses type I interferon signalling in rainbow trout gonad cell line but not in Atlantic salmon macrophages.

Fish Shellfish Immunol 2007 Jan-Feb;22(1-2):44-56. Epub 2006 Mar 28.

Marine Laboratory, 375 Victoria Road, Aberdeen AB11 9DB, Scotland, UK.

RTG-P1 cells are a rainbow trout fibroblastic cell line permanently transfected with the luciferase gene under the control of the Mx promoter. On exposure to interferon (IFN) or IFN inducing agents, the cells produce luciferase. IPNV did not induce luciferase production up to 24h post-infection but did not suppress constitutive luciferase production. Furthermore, IPNV suppressed luciferase production induced by poly I:C. RT-PCR analysis of IPNV infected cells showed IFN gene transcription from 6h post-infection with increasing expression up to 24h. Housekeeping genes beta-actin and GAPDH were also expressed along with upregulation of IRF1 and slight upregulation of STAT1. When RTG-P1 cells were stimulated with IFN, Mx transcripts, measured by qRT-PCR, peaked at 3-6h and thereafter fell to low levels, but in the presence of IPNV, Mx transcription at this time was significantly suppressed but continued to rise gradually. Luciferase production was lower in infected cells at 12h post-infection but not significantly after 24h. These results indicate that, in non-stimulated RTG-P1 cells, while IPNV induces IFN transcription, activation of Mx expression is suppressed. Furthermore, when stimulated by IFN, the rate of Mx transcription is significantly suppressed by the virus. This would probably give time for the virus to replicate rapidly in the early phases of infection. Contrary to the fibroblastic cell line, IPNV stimulated IFN production by salmon macrophages in vitro at least as strongly as poly I:C, with no suppression of the IFN response to poly I:C, and the virus persisted for up to 9 days without causing CPE.
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http://dx.doi.org/10.1016/j.fsi.2006.03.011DOI Listing
June 2008