Vishal Tiwari - Academia.edu (original) (raw)

Papers by Vishal Tiwari

Occupational and Environmental Medicine, 1990

A follow up study three years after exposure to methyl isocyanate in 93% of exposed survivors and... more A follow up study three years after exposure to methyl isocyanate in 93% of exposed survivors and "control" residents in 10 Bhopali communities showed an excess of eye irritation, eyelid infection, cataract, and a decrease in visual acuity among the exposed people. Breathlessness was twice as common in the heavily exposed clusters as those with lower exposure, a trend that could not be explained by different age or smoking patterns (OR 2.05, 95% CI 1.36-3.08). Case referent analysis of outpatient attendances at Bhopal Eye Hospital, considering patients with severe refractive errors and astigmatism as "controls," showed a 40% increased risk of trachoma, 36% increased risk of other lid infections, and 45% increased risk of irritant symptoms among previously exposed people. "Bhopal eye syndrome" may thus include full resolution of the initial interpalpebral superficial erosion, a subsequent increased risk of eye infections, hyperresponsive phenomena (irritation, watering, and phlyctens), and possibly cataracts. It remains to be confirmed whether this reflects a more generalised disease as a consequence of previous exposure to methyl isocyanate or whether it is only the eye that is affected.

Journal of Physiology and Biochemistry, 2011

The present study was undertaken to assess the chronology of major pathological events associated... more The present study was undertaken to assess the chronology of major pathological events associated with high cholesterol (HC) diet and their modulation by anti-platelet drugs. Male Golden Syrian hamsters were fed HC diet up to 90 days. Plasma lipid, glucose and coagulation parameters (commercial kits), platelet activation (whole blood aggregation and static adhesion), endothelial dysfunction (aortic ring vasoreactivity), splenocyte TNF-α, IFN-γ and iNOS mRNA transcripts (RT–PCR), and ferric chloride (time to occlusion) induced thrombosis were monitored at 15, 30, 60, and 90 days after HC feeding and compared with normolipidemic hamsters. A significant increase in plasma lipid levels was observed at 15 days of HC feeding, but other parameters remain unaltered. Enhanced ADP, collagen, and thrombin-induced platelet aggregation, splenocyte TNF-α expression along with endothelial dysfunction were observed from 30 to 90 days of HC feeding. Platelet adhesion on collagen-/fibrinogen-coated surface and IFN-γ expression were augmented only after 60 days, while enhanced iNOS expression, reduction in thrombin time, and potentiation of ferric chloride-induced thrombosis was observed only at 90 days of HC feeding. Thus, pathological changes induced by HC diet depend on the duration and extent of hyperlipidemia. Moreover, hamsters treated with anti-platelet drugs aspirin (5 mg/kg) or clopidogrel (10 mg/kg) along with HC feeding exhibited reduction in platelet activation as well as subsequent changes observed in the abovementioned parameters following HC feeding. Since reduction in TNF-α was associated with reversion in endothelial dysfunction and prothrombotic state, the role of platelets is implicated in the pathological changes associated with HC feeding.

This is global challenge to preserve the soft computing data through hard device. By this issue i... more This is global challenge to preserve the soft computing data through hard device. By this issue in the field of Computer science and Engineering Technology, the data collection and capturing techniques together with algorithms for combining multiple range, allow us to accurately digitize the internal and external characteristics of many soft computing and hard devices. This capability makes it possible

Indian Journal of Thoracic and Cardiovascular Surgery, 2008

A case report of pure endobronchial chondroma causing obstruction of right main bronchus is prese... more A case report of pure endobronchial chondroma causing obstruction of right main bronchus is presented. The features of this rare tumour at an uncommon site is discussed along with an overview of benign airway tumours.

Understanding the nature of novelty is a crucial first step in managing the changes associated wi... more Understanding the nature of novelty is a crucial first step in managing the changes associated with any novelty. The objectives of this paper are therefore to: (1) elucidate the major changes from Web-based commerce to M-commerce using the hypercube novelty model, (2) ...

Current Vascular Pharmacology, 2009

The recent failure of candidate drugs like cholesterol ester transfer protein (CETP) and acyl-CoA... more The recent failure of candidate drugs like cholesterol ester transfer protein (CETP) and acyl-CoA:cholesterol acyltransferase (ACAT) inhibitors calls for a revised approach for screening anti-atherosclerotic drugs and development of new models of atherosclerosis. For this it is important to understand the mechanism of the disease in a particular model. Models simultaneously showing hyperlipidemia, inflammation and associated complications of diabetes and hypertension will serve the purpose better as they mimic the actual clinical condition. Besides this, analyzing candidate molecules in vivo, in vitro and at various levels of atherosclerosis progression is important. Models based on various cells and process involved in atherosclerosis should be used for screening candidate molecules. The challenge lies in bridging the gap between genetically friendly small animal and human-like bigger animal models. Sequencing of the mouse and human genome, development of a single nucleotide polymorphism (SNP) database and in silico quantitative trait loci (QTL) linkage analysis may enhance the understanding of atherosclerosis and help develop new therapeutic targets.

Materials Science and Engineering B-advanced Functional Solid-state Materials, 1996

At/PMMA composites containing different volume fractions of atuminium were prepared by attritor m... more At/PMMA composites containing different volume fractions of atuminium were prepared by attritor milling followed by hot pressing and their thermal expansion and electrical behaviour were studied. Room temperature resistivity of these composites dropped by several orders of magnitude when the volume percent of aluminium ranged between 20 and 40 vol.%. MicrostructuraI examination revealed the presence of continuous chains of aluminium in highly conducting composites. The dielectric constant and dissipation factor of the composites increased with increase in aluminium content. This has been attributed to the interracial polarization associated with aluminium particles.

Journal of Radioanalytical and Nuclear Chemistry, 1996

Adsorption behavior of zinc ions on hydrous zirconium oxide (HZO) in aqueous solution has been st... more Adsorption behavior of zinc ions on hydrous zirconium oxide (HZO) in aqueous solution has been studied as a function of concentration (10−2–10−8M), temperature (303–333 K) and pH 3–8 of adsorptive solution applying radiotracer technique. The kinetics of adsorption follows first order rate law and agrees well with the classical Freundlich isotherm in the entire range of adsorptive concentration. The removal was found to be increasing with pH of the adsorptive solution while it was suppressed in the presence of acid concentrations. The overall process is found to be endothermic and irreversible in nature.

Journal of Physics-condensed Matter, 2007

We present results of detailed ac susceptibility, magnetization and specific heat measurements in... more We present results of detailed ac susceptibility, magnetization and specific heat measurements in Heusler alloys Ni50Mn34In16 and Ni50Mn34Sn16. These alloys undergo a paramagnetic to ferromagnetic transition around 305 K, which is followed by a martensitic transition in the temperature regime around 220 K. Inside the martensite phase both the alloys show signatures of field-induced transition from martensite to austenite phase. Both field- and temperature-induced martensite-austenite transitions are relatively sharp in Ni50Mn34In16. We estimate the isothermal magnetic entropy change and adiabatic temperature change across the various phase transitions in these alloys and investigate the possible influence of these transitions on the estimated magnetocaloric effect. The sharp martensitic transition in Ni50Mn34In16 gives rise to a comparatively large inverse magnetocaloric effect across this transition. On the other hand the magnitudes of the conventional magnetocaloric effect associated with the paramagnetic to ferromagnetic transition are quite comparable in these alloys.

Medicinal Research Reviews, 2008

Macrophages are central to the initiation and progression of atherosclerosis and thus can be very... more Macrophages are central to the initiation and progression of atherosclerosis and thus can be very appropriate targets for therapy. Cell adhesion molecules mediating monocytes recruitment to the endothelium are attractive therapy targets and their inhibitors are in clinical trials. Macrophage scavenger receptors like SR-A and CD-36 mediate foam cell formation by facilitating the uptake of modified lipids. Peroxisome proliferator-activated receptors (PPAR), liver X receptor (LXR)-mediated signaling, mitogen-activated protein kinase (MAPK) induced phosphorylation events seem to play an important role in this phenomenon. Proteins affecting macrophage cholesterol metabolism and transport, including ATP-binding cassette (ABC) A1, ABCG1, acyl-CoA:cholesterol acyltransferase (ACAT), apolipoprotein A-1 (ApoA-1), neutral cholesteryl ester hydrolase (NCEH) also regulate foam cell formation and are being developed as therapeutic targets by many pharmaceutical companies. Macrophage proliferation and apoptosis are important events controlling inflammatory response, plaque vulnerability, and destabilization. Free cholesterol (FC) activates the macrophage endoplasmic reticulum (ER) stress pathway and apoptosis. Free radicals and nitric oxide also modulate macrophage foam cell formation and apoptosis. Various antioxidants like AGI-1067 and BO-653 are in clinical trials for atherosclerosis treatment. Macrophage matrix metalloproteinase's (MMP's) play a significant role in weakening and rupture of plaques. Efforts are on to develop isoform specific MMP inhibitor. CD-14, MMP-3, ABCA1, Toll-like receptor-4 (TLR-4), lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), arachidonate lipoxygenase-15 (ALOX-15), and Connexin37 polymorphisms and macrophage dysfunction signify their importance in atherosclerosis. Deciphering the role of macrophages in regulating dyslipidemia and inflammation during atherosclerosis is important for developing them as therapeutic targets. © 2007 Wiley Periodicals, Inc. Med Res Rev, 28, No. 4, 483–544, 2008

Journal of Applied Physics, 2010

We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiom... more We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiometric Heusler alloys Ni50Mn35In15 and Ni50Mn34.5In15.5 as functions of temperature and magnetic field. The results show that the alloy system is more sensitive to the composition than what is apparent from the established phase diagram. We have found that the ground states as well as the nature of phase transitions strongly depend on concentration differences as low as 0.5 at. %. While in the case of Ni50Mn34.5In15.5 we do observe a magnetic field induced martensite to austenite phase transition, there is no detectable signature of any field induced transition in the Ni50Mn35In15 alloy even up to fields as high as 80 kOe. Accordingly, the functional properties of these two alloys are also drastically different.

Molecular and Cellular Biochemistry, 2005

Salmonella enterica serovar Typhimurium and its surface components were assessed for their inflam... more Salmonella enterica serovar Typhimurium and its surface components were assessed for their inflammatory potential by footpad oedema test using plethysmometer. Inflammation was found to be the highest when outer membrane proteins (OMPs) were used as inflammagen followed by lipid associated protein-lipopolysaccharide complex (LAP-LPS) and lipopolysaccharides (LPS). Inflammation produced by OMPs was found to be comparable to that by carrageenan (a known positive inflammagen). However, injection of L-histidine (an antioxidant) prior to administration of carrageenan or Salmonella enterica serovar Typhimurium inhibited the inflammation, which indicated the involvement of oxidants during inflammatory response. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and nitric oxide (NO) production by peritoneal macrophages from infected mice exhibited a significant increase as compared to those of the immunized mice. In contrast, glutathione production was found to be the maximum in the macrophages taken from OMPs-immunized mice followed by LAP-LPS and LPS alone. The biochemical studies correlated well with histopathological studies of intestinal tissue of animals from various groups. Based upon these parameters, inflammation seems to be modulated by OMPs and LAP-LPS, which may be because of the protein moieties present in the components. Hence, immunization with protein moieties having L-histidine or L-histidine-like structures may suggest an alternative to the potential therapeutic values of anti-inflammatory drugs. Thus the results of this study form the basis for evaluating these antigens (either alone or in combination with polysaccharides) for preventive intervention rather than therapeutic. (Mol Cell Biochem 270: 167–175, 2005)

World Journal of Microbiology & Biotechnology, 2004

Salmonella spp. have been shown to cause apoptosis of various host cell types as a part of their ... more Salmonella spp. have been shown to cause apoptosis of various host cell types as a part of their infection process. However, the induction of apoptosis remains to be looked into under the different host environments experienced by the pathogens. One of these is iron limitation, due to binding of iron in the host with proteins like lactoferrin, transferrin, haptoglobulin and hemoglobin etc. making non-availability of free iron to the pathogen for its growth and metabolism. In order to simulate the iron-limited in vivo situation, we studied the potential of Salmonella enterica serovar Typhimurium and its proteins under in vitro-created iron-stressed conditions, to cause apoptosis of macrophages (the first line of defence system). The apoptotic potential was evaluated qualitatively and quantitatively by various methods like assessment of nucleosomal DNA ladder (hallmark of apoptosis) and morphological evaluation by DNA intercalating dyes like acridine orange staining and Hoechst 33342-propidium iodide co-staining. It was observed that iron limitation could cause apoptotic cell death in a higher number of cells with the overexpression of proteins with subunit molecular weights of approximately 89, 54, 32 and 20 kDa. Salmonella may initiate apoptosis as a virulence strategy, but the death of host cells by the process of apoptosis rather than necrosis after getting a suicidal signal might be helpful for the host in order to save the surrounding cells, as well as to the parasite to enable it to spread systemically without inducing an inflammatory response.

Journal of Physics-condensed Matter, 2010

The potential shape memory alloy Ni50Mn34In16 is studied with partial substitution of Mn with Fe ... more The potential shape memory alloy Ni50Mn34In16 is studied with partial substitution of Mn with Fe and Cr to investigate the effect of such substitution on the martensitic transition in the Ni-Mn-In alloy system. The results of ac susceptibility, magnetization and electrical resistivity measurements show that while the substitution with Cr increases the martensitic transition temperature, the substitution with Fe decreases it. Possible reasons for this shift in martensitic transition are discussed. Evidence of kinetic arrest of the austenite to martensite phase transition in the Fe substituted alloys is also presented. Unlike the kinetic arrest of the austenite to martensite phase transition in the parent Ni50Mn34In16 alloy which takes place in the presence of high external magnetic field, the kinetic arrest of the austenite to martensite phase transition in the Fe doped alloy occurs even in zero magnetic field. The Cr substituted alloys, on the other hand, show no signature of kinetic arrest of this phase transition.

Journal of Physics-condensed Matter, 2010

The potential shape memory alloy Ni50Mn34In16 is studied with partial substitution of Mn with Fe ... more The potential shape memory alloy Ni50Mn34In16 is studied with partial substitution of Mn with Fe and Cr to investigate the effect of such substitution on the martensitic transition in the Ni-Mn-In alloy system. The results of ac susceptibility, magnetization and electrical resistivity measurements show that while the substitution with Cr increases the martensitic transition temperature, the substitution with Fe decreases it. Possible reasons for this shift in martensitic transition are discussed. Evidence of kinetic arrest of the austenite to martensite phase transition in the Fe substituted alloys is also presented. Unlike the kinetic arrest of the austenite to martensite phase transition in the parent Ni50Mn34In16 alloy which takes place in the presence of high external magnetic field, the kinetic arrest of the austenite to martensite phase transition in the Fe doped alloy occurs even in zero magnetic field. The Cr substituted alloys, on the other hand, show no signature of kinetic arrest of this phase transition.

Abstract The glitch of providing recommendations to the visitors of a web site has received a sig... more Abstract The glitch of providing recommendations to the visitors of a web site has received a significant amount of attention in recent years. To address this requirement, web sites provide personalized recommendations to the end users. When a personalization system ...

We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiom... more We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiometric Heusler alloys Ni 50 Mn 35 In 15 and Ni 50 Mn 34.5 In 15.5 as functions of temperature and magnetic field. The results show that the alloy system is more sensitive to the composition than what is apparent from the established phase diagram. We have found that the ground states as well as the nature of phase transitions strongly depend on concentration differences as low as 0.5 at. %. While in the case of Ni 50 Mn 34.5 In 15.5 we do observe a magnetic field induced martensite to austenite phase transition, there is no detectable signature of any field induced transition in the Ni 50 Mn 35 In 15 alloy even up to fields as high as 80 kOe. Accordingly, the functional properties of these two alloys are also drastically different.

International Journal of Dermatology, 2009

A 52-year-old man presented with a 3-month history of a slowly progressive, asymptomatic lesion o... more A 52-year-old man presented with a 3-month history of a slowly progressive, asymptomatic lesion on the right foot that had failed to respond to topical antifungal and antibacterial medications. He had been on azathioprine (75 mg/day) and prednisolone (7.5 mg/day) for a live related renal transplant 17 years earlier. He remained systemically well with good graft function. There were no symptoms suggestive of pulmonary tuberculosis (TB). There was no personal or family history of pulmonary TB.

Electromagnetic Biology and Medicine, 2008

The aim of present study is to assess DNA integrity on the effect of exposure to a radio frequenc... more The aim of present study is to assess DNA integrity on the effect of exposure to a radio frequency (RF) signal from Code Division Multiple Access (CDMA) mobile phones. Whole blood samples from six healthy male individuals were exposed for RF signals from a CDMA mobile phone for 1 h. Alkaline comet assay was performed to assess the DNA damage. The combinative exposure effect of the RF signals and APC at two concentrations on DNA integrity was studied. DNA repair efficiency of the samples was also studied after 2 h of exposure. The RF signals and APC (0.2 microg/ml) alone or in synergism did not have any significant DNA damage as compared to sham exposed. However, univariate analysis showed that DNA damage was significantly different among combinative exposure of RF signals and APC at 0.2 microg/ml (p < 0.05) and at 2 microg/ml (p < 0.02). APC at 2 microg/ml concentration also showed significant damage levels (p < 0.05) when compared to sham exposed. DNA repair efficiency also varied in a significant way in combinative exposure sets (p < 0.05). From these results, it appears that the repair inhibitor APC enhances DNA breaks at 2 microg/ml concentration and that the damage is possibly repairable. Thus, it can be inferred that the in vitro exposure to RF signals induces reversible DNA damage in synergism with APC.

Analytica Chimica Acta, 2008

Liquid chromatography with amperometric oxidative detection is proposed as a sensitive method for... more Liquid chromatography with amperometric oxidative detection is proposed as a sensitive method for the determination of aliphatic amines previously converted in thioureido derivatives by reaction with phenylisothiocyanate (PIT). The phenylthioureas of four model amines, methylamine (MA), propylamine (PA), n-butylamine (BA) and isobutylamine (IBA) have been synthesized and isolated. Their electrochemical behavior on a glassy carbon electrode has been explored by cyclic voltammetry. The thioureido derivatives can be oxidized through two one-electron steps at acidic pH values, presumably involving the intermediacy of proton transfers. A mechanistic pathway is also proposed on the basis of experimental data. Liquid chromatographic parameters as mobile phase composition and¯ow rate, temperature and working electrode potential have been optimized. The method permits the simultaneous determination of the phenylthioureas of the selected amines with detection limits in the lower mgL 71 range.

Occupational and Environmental Medicine, 1990

A follow up study three years after exposure to methyl isocyanate in 93% of exposed survivors and... more A follow up study three years after exposure to methyl isocyanate in 93% of exposed survivors and "control" residents in 10 Bhopali communities showed an excess of eye irritation, eyelid infection, cataract, and a decrease in visual acuity among the exposed people. Breathlessness was twice as common in the heavily exposed clusters as those with lower exposure, a trend that could not be explained by different age or smoking patterns (OR 2.05, 95% CI 1.36-3.08). Case referent analysis of outpatient attendances at Bhopal Eye Hospital, considering patients with severe refractive errors and astigmatism as "controls," showed a 40% increased risk of trachoma, 36% increased risk of other lid infections, and 45% increased risk of irritant symptoms among previously exposed people. "Bhopal eye syndrome" may thus include full resolution of the initial interpalpebral superficial erosion, a subsequent increased risk of eye infections, hyperresponsive phenomena (irritation, watering, and phlyctens), and possibly cataracts. It remains to be confirmed whether this reflects a more generalised disease as a consequence of previous exposure to methyl isocyanate or whether it is only the eye that is affected.

Journal of Physiology and Biochemistry, 2011

The present study was undertaken to assess the chronology of major pathological events associated... more The present study was undertaken to assess the chronology of major pathological events associated with high cholesterol (HC) diet and their modulation by anti-platelet drugs. Male Golden Syrian hamsters were fed HC diet up to 90 days. Plasma lipid, glucose and coagulation parameters (commercial kits), platelet activation (whole blood aggregation and static adhesion), endothelial dysfunction (aortic ring vasoreactivity), splenocyte TNF-α, IFN-γ and iNOS mRNA transcripts (RT–PCR), and ferric chloride (time to occlusion) induced thrombosis were monitored at 15, 30, 60, and 90 days after HC feeding and compared with normolipidemic hamsters. A significant increase in plasma lipid levels was observed at 15 days of HC feeding, but other parameters remain unaltered. Enhanced ADP, collagen, and thrombin-induced platelet aggregation, splenocyte TNF-α expression along with endothelial dysfunction were observed from 30 to 90 days of HC feeding. Platelet adhesion on collagen-/fibrinogen-coated surface and IFN-γ expression were augmented only after 60 days, while enhanced iNOS expression, reduction in thrombin time, and potentiation of ferric chloride-induced thrombosis was observed only at 90 days of HC feeding. Thus, pathological changes induced by HC diet depend on the duration and extent of hyperlipidemia. Moreover, hamsters treated with anti-platelet drugs aspirin (5 mg/kg) or clopidogrel (10 mg/kg) along with HC feeding exhibited reduction in platelet activation as well as subsequent changes observed in the abovementioned parameters following HC feeding. Since reduction in TNF-α was associated with reversion in endothelial dysfunction and prothrombotic state, the role of platelets is implicated in the pathological changes associated with HC feeding.

This is global challenge to preserve the soft computing data through hard device. By this issue i... more This is global challenge to preserve the soft computing data through hard device. By this issue in the field of Computer science and Engineering Technology, the data collection and capturing techniques together with algorithms for combining multiple range, allow us to accurately digitize the internal and external characteristics of many soft computing and hard devices. This capability makes it possible

Indian Journal of Thoracic and Cardiovascular Surgery, 2008

A case report of pure endobronchial chondroma causing obstruction of right main bronchus is prese... more A case report of pure endobronchial chondroma causing obstruction of right main bronchus is presented. The features of this rare tumour at an uncommon site is discussed along with an overview of benign airway tumours.

Understanding the nature of novelty is a crucial first step in managing the changes associated wi... more Understanding the nature of novelty is a crucial first step in managing the changes associated with any novelty. The objectives of this paper are therefore to: (1) elucidate the major changes from Web-based commerce to M-commerce using the hypercube novelty model, (2) ...

Current Vascular Pharmacology, 2009

The recent failure of candidate drugs like cholesterol ester transfer protein (CETP) and acyl-CoA... more The recent failure of candidate drugs like cholesterol ester transfer protein (CETP) and acyl-CoA:cholesterol acyltransferase (ACAT) inhibitors calls for a revised approach for screening anti-atherosclerotic drugs and development of new models of atherosclerosis. For this it is important to understand the mechanism of the disease in a particular model. Models simultaneously showing hyperlipidemia, inflammation and associated complications of diabetes and hypertension will serve the purpose better as they mimic the actual clinical condition. Besides this, analyzing candidate molecules in vivo, in vitro and at various levels of atherosclerosis progression is important. Models based on various cells and process involved in atherosclerosis should be used for screening candidate molecules. The challenge lies in bridging the gap between genetically friendly small animal and human-like bigger animal models. Sequencing of the mouse and human genome, development of a single nucleotide polymorphism (SNP) database and in silico quantitative trait loci (QTL) linkage analysis may enhance the understanding of atherosclerosis and help develop new therapeutic targets.

Materials Science and Engineering B-advanced Functional Solid-state Materials, 1996

At/PMMA composites containing different volume fractions of atuminium were prepared by attritor m... more At/PMMA composites containing different volume fractions of atuminium were prepared by attritor milling followed by hot pressing and their thermal expansion and electrical behaviour were studied. Room temperature resistivity of these composites dropped by several orders of magnitude when the volume percent of aluminium ranged between 20 and 40 vol.%. MicrostructuraI examination revealed the presence of continuous chains of aluminium in highly conducting composites. The dielectric constant and dissipation factor of the composites increased with increase in aluminium content. This has been attributed to the interracial polarization associated with aluminium particles.

Journal of Radioanalytical and Nuclear Chemistry, 1996

Adsorption behavior of zinc ions on hydrous zirconium oxide (HZO) in aqueous solution has been st... more Adsorption behavior of zinc ions on hydrous zirconium oxide (HZO) in aqueous solution has been studied as a function of concentration (10−2–10−8M), temperature (303–333 K) and pH 3–8 of adsorptive solution applying radiotracer technique. The kinetics of adsorption follows first order rate law and agrees well with the classical Freundlich isotherm in the entire range of adsorptive concentration. The removal was found to be increasing with pH of the adsorptive solution while it was suppressed in the presence of acid concentrations. The overall process is found to be endothermic and irreversible in nature.

Journal of Physics-condensed Matter, 2007

We present results of detailed ac susceptibility, magnetization and specific heat measurements in... more We present results of detailed ac susceptibility, magnetization and specific heat measurements in Heusler alloys Ni50Mn34In16 and Ni50Mn34Sn16. These alloys undergo a paramagnetic to ferromagnetic transition around 305 K, which is followed by a martensitic transition in the temperature regime around 220 K. Inside the martensite phase both the alloys show signatures of field-induced transition from martensite to austenite phase. Both field- and temperature-induced martensite-austenite transitions are relatively sharp in Ni50Mn34In16. We estimate the isothermal magnetic entropy change and adiabatic temperature change across the various phase transitions in these alloys and investigate the possible influence of these transitions on the estimated magnetocaloric effect. The sharp martensitic transition in Ni50Mn34In16 gives rise to a comparatively large inverse magnetocaloric effect across this transition. On the other hand the magnitudes of the conventional magnetocaloric effect associated with the paramagnetic to ferromagnetic transition are quite comparable in these alloys.

Medicinal Research Reviews, 2008

Macrophages are central to the initiation and progression of atherosclerosis and thus can be very... more Macrophages are central to the initiation and progression of atherosclerosis and thus can be very appropriate targets for therapy. Cell adhesion molecules mediating monocytes recruitment to the endothelium are attractive therapy targets and their inhibitors are in clinical trials. Macrophage scavenger receptors like SR-A and CD-36 mediate foam cell formation by facilitating the uptake of modified lipids. Peroxisome proliferator-activated receptors (PPAR), liver X receptor (LXR)-mediated signaling, mitogen-activated protein kinase (MAPK) induced phosphorylation events seem to play an important role in this phenomenon. Proteins affecting macrophage cholesterol metabolism and transport, including ATP-binding cassette (ABC) A1, ABCG1, acyl-CoA:cholesterol acyltransferase (ACAT), apolipoprotein A-1 (ApoA-1), neutral cholesteryl ester hydrolase (NCEH) also regulate foam cell formation and are being developed as therapeutic targets by many pharmaceutical companies. Macrophage proliferation and apoptosis are important events controlling inflammatory response, plaque vulnerability, and destabilization. Free cholesterol (FC) activates the macrophage endoplasmic reticulum (ER) stress pathway and apoptosis. Free radicals and nitric oxide also modulate macrophage foam cell formation and apoptosis. Various antioxidants like AGI-1067 and BO-653 are in clinical trials for atherosclerosis treatment. Macrophage matrix metalloproteinase's (MMP's) play a significant role in weakening and rupture of plaques. Efforts are on to develop isoform specific MMP inhibitor. CD-14, MMP-3, ABCA1, Toll-like receptor-4 (TLR-4), lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), arachidonate lipoxygenase-15 (ALOX-15), and Connexin37 polymorphisms and macrophage dysfunction signify their importance in atherosclerosis. Deciphering the role of macrophages in regulating dyslipidemia and inflammation during atherosclerosis is important for developing them as therapeutic targets. © 2007 Wiley Periodicals, Inc. Med Res Rev, 28, No. 4, 483–544, 2008

Journal of Applied Physics, 2010

We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiom... more We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiometric Heusler alloys Ni50Mn35In15 and Ni50Mn34.5In15.5 as functions of temperature and magnetic field. The results show that the alloy system is more sensitive to the composition than what is apparent from the established phase diagram. We have found that the ground states as well as the nature of phase transitions strongly depend on concentration differences as low as 0.5 at. %. While in the case of Ni50Mn34.5In15.5 we do observe a magnetic field induced martensite to austenite phase transition, there is no detectable signature of any field induced transition in the Ni50Mn35In15 alloy even up to fields as high as 80 kOe. Accordingly, the functional properties of these two alloys are also drastically different.

Molecular and Cellular Biochemistry, 2005

Salmonella enterica serovar Typhimurium and its surface components were assessed for their inflam... more Salmonella enterica serovar Typhimurium and its surface components were assessed for their inflammatory potential by footpad oedema test using plethysmometer. Inflammation was found to be the highest when outer membrane proteins (OMPs) were used as inflammagen followed by lipid associated protein-lipopolysaccharide complex (LAP-LPS) and lipopolysaccharides (LPS). Inflammation produced by OMPs was found to be comparable to that by carrageenan (a known positive inflammagen). However, injection of L-histidine (an antioxidant) prior to administration of carrageenan or Salmonella enterica serovar Typhimurium inhibited the inflammation, which indicated the involvement of oxidants during inflammatory response. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and nitric oxide (NO) production by peritoneal macrophages from infected mice exhibited a significant increase as compared to those of the immunized mice. In contrast, glutathione production was found to be the maximum in the macrophages taken from OMPs-immunized mice followed by LAP-LPS and LPS alone. The biochemical studies correlated well with histopathological studies of intestinal tissue of animals from various groups. Based upon these parameters, inflammation seems to be modulated by OMPs and LAP-LPS, which may be because of the protein moieties present in the components. Hence, immunization with protein moieties having L-histidine or L-histidine-like structures may suggest an alternative to the potential therapeutic values of anti-inflammatory drugs. Thus the results of this study form the basis for evaluating these antigens (either alone or in combination with polysaccharides) for preventive intervention rather than therapeutic. (Mol Cell Biochem 270: 167–175, 2005)

World Journal of Microbiology & Biotechnology, 2004

Salmonella spp. have been shown to cause apoptosis of various host cell types as a part of their ... more Salmonella spp. have been shown to cause apoptosis of various host cell types as a part of their infection process. However, the induction of apoptosis remains to be looked into under the different host environments experienced by the pathogens. One of these is iron limitation, due to binding of iron in the host with proteins like lactoferrin, transferrin, haptoglobulin and hemoglobin etc. making non-availability of free iron to the pathogen for its growth and metabolism. In order to simulate the iron-limited in vivo situation, we studied the potential of Salmonella enterica serovar Typhimurium and its proteins under in vitro-created iron-stressed conditions, to cause apoptosis of macrophages (the first line of defence system). The apoptotic potential was evaluated qualitatively and quantitatively by various methods like assessment of nucleosomal DNA ladder (hallmark of apoptosis) and morphological evaluation by DNA intercalating dyes like acridine orange staining and Hoechst 33342-propidium iodide co-staining. It was observed that iron limitation could cause apoptotic cell death in a higher number of cells with the overexpression of proteins with subunit molecular weights of approximately 89, 54, 32 and 20 kDa. Salmonella may initiate apoptosis as a virulence strategy, but the death of host cells by the process of apoptosis rather than necrosis after getting a suicidal signal might be helpful for the host in order to save the surrounding cells, as well as to the parasite to enable it to spread systemically without inducing an inflammatory response.

Journal of Physics-condensed Matter, 2010

The potential shape memory alloy Ni50Mn34In16 is studied with partial substitution of Mn with Fe ... more The potential shape memory alloy Ni50Mn34In16 is studied with partial substitution of Mn with Fe and Cr to investigate the effect of such substitution on the martensitic transition in the Ni-Mn-In alloy system. The results of ac susceptibility, magnetization and electrical resistivity measurements show that while the substitution with Cr increases the martensitic transition temperature, the substitution with Fe decreases it. Possible reasons for this shift in martensitic transition are discussed. Evidence of kinetic arrest of the austenite to martensite phase transition in the Fe substituted alloys is also presented. Unlike the kinetic arrest of the austenite to martensite phase transition in the parent Ni50Mn34In16 alloy which takes place in the presence of high external magnetic field, the kinetic arrest of the austenite to martensite phase transition in the Fe doped alloy occurs even in zero magnetic field. The Cr substituted alloys, on the other hand, show no signature of kinetic arrest of this phase transition.

Journal of Physics-condensed Matter, 2010

The potential shape memory alloy Ni50Mn34In16 is studied with partial substitution of Mn with Fe ... more The potential shape memory alloy Ni50Mn34In16 is studied with partial substitution of Mn with Fe and Cr to investigate the effect of such substitution on the martensitic transition in the Ni-Mn-In alloy system. The results of ac susceptibility, magnetization and electrical resistivity measurements show that while the substitution with Cr increases the martensitic transition temperature, the substitution with Fe decreases it. Possible reasons for this shift in martensitic transition are discussed. Evidence of kinetic arrest of the austenite to martensite phase transition in the Fe substituted alloys is also presented. Unlike the kinetic arrest of the austenite to martensite phase transition in the parent Ni50Mn34In16 alloy which takes place in the presence of high external magnetic field, the kinetic arrest of the austenite to martensite phase transition in the Fe doped alloy occurs even in zero magnetic field. The Cr substituted alloys, on the other hand, show no signature of kinetic arrest of this phase transition.

Abstract The glitch of providing recommendations to the visitors of a web site has received a sig... more Abstract The glitch of providing recommendations to the visitors of a web site has received a significant amount of attention in recent years. To address this requirement, web sites provide personalized recommendations to the end users. When a personalization system ...

We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiom... more We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiometric Heusler alloys Ni 50 Mn 35 In 15 and Ni 50 Mn 34.5 In 15.5 as functions of temperature and magnetic field. The results show that the alloy system is more sensitive to the composition than what is apparent from the established phase diagram. We have found that the ground states as well as the nature of phase transitions strongly depend on concentration differences as low as 0.5 at. %. While in the case of Ni 50 Mn 34.5 In 15.5 we do observe a magnetic field induced martensite to austenite phase transition, there is no detectable signature of any field induced transition in the Ni 50 Mn 35 In 15 alloy even up to fields as high as 80 kOe. Accordingly, the functional properties of these two alloys are also drastically different.

International Journal of Dermatology, 2009

A 52-year-old man presented with a 3-month history of a slowly progressive, asymptomatic lesion o... more A 52-year-old man presented with a 3-month history of a slowly progressive, asymptomatic lesion on the right foot that had failed to respond to topical antifungal and antibacterial medications. He had been on azathioprine (75 mg/day) and prednisolone (7.5 mg/day) for a live related renal transplant 17 years earlier. He remained systemically well with good graft function. There were no symptoms suggestive of pulmonary tuberculosis (TB). There was no personal or family history of pulmonary TB.

Electromagnetic Biology and Medicine, 2008

The aim of present study is to assess DNA integrity on the effect of exposure to a radio frequenc... more The aim of present study is to assess DNA integrity on the effect of exposure to a radio frequency (RF) signal from Code Division Multiple Access (CDMA) mobile phones. Whole blood samples from six healthy male individuals were exposed for RF signals from a CDMA mobile phone for 1 h. Alkaline comet assay was performed to assess the DNA damage. The combinative exposure effect of the RF signals and APC at two concentrations on DNA integrity was studied. DNA repair efficiency of the samples was also studied after 2 h of exposure. The RF signals and APC (0.2 microg/ml) alone or in synergism did not have any significant DNA damage as compared to sham exposed. However, univariate analysis showed that DNA damage was significantly different among combinative exposure of RF signals and APC at 0.2 microg/ml (p < 0.05) and at 2 microg/ml (p < 0.02). APC at 2 microg/ml concentration also showed significant damage levels (p < 0.05) when compared to sham exposed. DNA repair efficiency also varied in a significant way in combinative exposure sets (p < 0.05). From these results, it appears that the repair inhibitor APC enhances DNA breaks at 2 microg/ml concentration and that the damage is possibly repairable. Thus, it can be inferred that the in vitro exposure to RF signals induces reversible DNA damage in synergism with APC.

Analytica Chimica Acta, 2008

Liquid chromatography with amperometric oxidative detection is proposed as a sensitive method for... more Liquid chromatography with amperometric oxidative detection is proposed as a sensitive method for the determination of aliphatic amines previously converted in thioureido derivatives by reaction with phenylisothiocyanate (PIT). The phenylthioureas of four model amines, methylamine (MA), propylamine (PA), n-butylamine (BA) and isobutylamine (IBA) have been synthesized and isolated. Their electrochemical behavior on a glassy carbon electrode has been explored by cyclic voltammetry. The thioureido derivatives can be oxidized through two one-electron steps at acidic pH values, presumably involving the intermediacy of proton transfers. A mechanistic pathway is also proposed on the basis of experimental data. Liquid chromatographic parameters as mobile phase composition and¯ow rate, temperature and working electrode potential have been optimized. The method permits the simultaneous determination of the phenylthioureas of the selected amines with detection limits in the lower mgL 71 range.