vivek kumar - Academia.edu (original) (raw)
Papers by vivek kumar
Toxicology International
The restorative potential of trans-resveratrol (RV) was investigated in a rat neuronal cell line ... more The restorative potential of trans-resveratrol (RV) was investigated in a rat neuronal cell line (PC12) exposed to organophosphate pesticide-monocrotophos (MCP). RV shows significant protection against MCP-induced alterations in PC12 cells by restoration of oxidative stress-mediated apoptosis and cytotoxicity. RV treatment significantly reduced reactive oxygen species (ROS) production and lipid peroxidation, and also restored glutathione levels and mitochondrial membrane potential, in cells receiving MCP. Restoration of markers such as cytochrome c, Bax, Bcl-2 and caspase-3 also confirms the effectiveness of RV against MCP-induced, mitochondria-mediated apoptosis in PC12 cells. The data identify the protective/restorative potential of RV against MCP-induced neuronal damages by affecting ROS production and the level of antioxidant defence enzymes.
Inhibition mechanisms of tyrosine kinase receptor TrkA and its consequences on apoptosis/ neurona... more Inhibition mechanisms of tyrosine kinase receptor TrkA and its consequences on apoptosis/ neuronal injury were investigated in rat brain neuronal stem cells (rBNSCs) exposed to monocrotophos (MCP, an organophosphate pesticide) and compared with staurosporine. The molecular docking study in GOLD docking program revealed that the staurosporine and MCP followed the similar binding pattern as with the AG-879 (well known TrkA inhibitor) and co-crystallized ligand of TrkA (PDB id: 4AOJ) respectively at the ATP binding domain. This led to the inhibition of TrkA and resulting cascades, though the structures of both the earlier molecules were signi"cantly different from the ATP as well as other well known inhibitors of TrkA. The main cause of MCP mediated TrkA inhibition is considered to be the water mediated Hbond interaction, and strong intraction with Met-592 similar to the co crystallized ligand. In silico data on TrkA inhibition was con"rmed by examining the down regulation of...
Attachment of newly formed crystals to renal epithe- lial cells appears to be a critical step in ... more Attachment of newly formed crystals to renal epithe- lial cells appears to be a critical step in the development of kidney stones. The current study was undertaken to identify potential calcium oxalate monohydrate (COM) crystal-binding proteins on the surface of renal tubular cells. Apical mem- branes were prepared from confluent monolayers of renal epithelial cells (MDCKI line), and COM crystal
Journal of Allergy and Clinical Immunology, 2004
RationaleThe abundance of allergenic Penicillium species has been associated with an increased in... more RationaleThe abundance of allergenic Penicillium species has been associated with an increased incidence of childhood asthma and pulmonary bleeding. Penicillium brevicompactum has been identified as the most prevalent indoor Penicillium species. However, detailed studies on allergen of the ubiquitous Penicillium species are still lacking. For the characterization of allergens of prevalent Penicillium species, molecular cloning of the allergen genes of
European Urology Supplements, 2009
International Journal of Plastics Technology, 2009
Pediatric Surgery International, 1993
Three hundred twenty infants underwent a Ramstedt pyloromyotomy for hypertrophic pyloric stenosis... more Three hundred twenty infants underwent a Ramstedt pyloromyotomy for hypertrophic pyloric stenosis, 182 via a transverse right hypochondrial incision and 138 via a circumumbilical incision. The overall rate of wound infections was 16% for operations performed via the umbilical approach compared with 5.5% for operations via a transverse approach despite a higher use of antibiotic prophylaxis (64% vs 13%). The
Journal of vector borne diseases, 2009
Visceral leishmaniasis, commonly known as kala-azar is endemic in Bihar state, India. Current vec... more Visceral leishmaniasis, commonly known as kala-azar is endemic in Bihar state, India. Current vector control programme in Bihar focuses mainly on spraying the sandfly infested dwellings with DDT. The Government of India in collaboration with WHO has fixed the target 2015 for total elimination of kala-azar. The present study was carried out to see the impact of DDT and improved IEC in the containment of vector density vis-à-vis disease transmission. Before the start of the spraying operations training was imparted to all the medical and paramedical personnel regarding the methods of spraying operations. Pre- and post-sandfly density was monitored in four selected districts. Incidences of kala-azar cases were compared for pre- and post-spray periods. Social acceptability and perceptions of households was collected through questionnaires from 500 randomly selected households in the study districts. House index in three study districts reduced considerably during post-spray when compare...
Tropical gastroenterology : official journal of the Digestive Diseases Foundation
The hepatitis B vaccine is considered to be highly immunogenic and has a good safety profile. In ... more The hepatitis B vaccine is considered to be highly immunogenic and has a good safety profile. In adults, it has a primary non-response rate of 5%-10%. Causes of nonresponse to hepatitis B vaccine include age, sex, obesity smoking. Certain human leucocyte antigen (HLA) phenotypes have been known to be associated with responsiveness to the vaccine, and found to be different in different ethnic groups, such as Caucasians and Orientals. The study was designed to identify the HLA phenotypes that are associated with non-responsiveness to hepatitis B virus (HBV) vaccination amongst a cohort of Indian subjects who agreed to participate in the vaccination programme. The study was offered to 107 volunteers, of whom 102 were found to be negative for HBV markers (hepatitis B surface antigen [HBsAg], anti-HBc, anti-HBe, anti-HBs, hepatitis Be antigen [HBeAg]) . All 102 volunteers were offered recombinant hepatitis B vaccine (20 microg) at 0, 1, and 6 months. Anti-HBs antibody titres were tested ...
Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists, 2008
Some parts of the Indian Himalayan region are covered by established and abandoned tea bushes. Rh... more Some parts of the Indian Himalayan region are covered by established and abandoned tea bushes. Rhizospheric soils of these plants were studied for bacterial dominance and antagonism. Representatives of Bacillus and Pseudomonas genera were found to dominate the rhizosphere of established and abandoned tea bushes, respectively. Amongst the isolated species Bacillus subtilis and Bacillus mycoides appeared to be closely associated with roots of established tea bushes while the rhizosphere of abandoned tea bushes was dominated by Pseudomonas putida. Four isolates of both B. subtilis and P. putida were selected on the basis of maximum antibacterial activity. The bacteriocin-like activity of B. subtilis and P putida strains was detected to be active over a range of temperature 0-50 degrees C and was sensitive to proteolytic enzymes. Incubation of indicator strains with different concentrations of bacteriocin-like substances confirmed their bactericidal activity. Various species of Bacillus...
The New Zealand medical journal, Jan 9, 2011
Veterinary Parasitology, 1999
In a series of three experiments, 64 jirds, Meriones unguiculatus, were infected with 700 infecti... more In a series of three experiments, 64 jirds, Meriones unguiculatus, were infected with 700 infective larvae of Trichostrongylus colubriformis for the study of several biological parameters of this laboratory host-parasite model. In jirds the third stage larvae of T. colubriformis were shown to reach the fourth larval stage by the Day 6 post-infection (PI). By Day 10 PI, all the worms harvested had reached the immature adult stage. All immature adult stages of T. colubriformis developed to sexually mature adult stage by Day 12 PI when the female worms showed developing eggs in their uteri. Developed eggs were observed in the uteri of females on Days 13 and 14 PI. The first eggs of T. colubriformis appeared in the faeces of jirds on Day 13 PI. The peaks of egg production were recorded between Day 21 and Day 31 PI. Immunosuppression of jirds infected with 700 L3, by administration of dexamethasone from Day 57 to Day 94 PI led to increased faecal egg count when compared to untreated controls. All the worms were located in the small intestine. The jirds of dexamethasone treated group harboured higher number of adult worms than those of the untreated group. The number of adult worms was significantly higher in the first part of the small intestine than in the three other similar parts of the small intestine. The coefficient of correlation between the faecal egg count and worm number on the day of necropsy of jirds ranged between r = 0.58 and r = 0.89. Patent infections in jirds were maintained till the end of experiment on Day 100 PI, indicating that in this host and unlike other laboratory hosts, T. colubriformis is responsible for long lasting infections similar to what happens in domestic ruminants. The results of the present study suggest that the jird is a suitable laboratory model to study various aspects of this host-parasite relationship.
This paper reports a template-based technique for the fabrication of polymer micro/nanofiber comp... more This paper reports a template-based technique for the fabrication of polymer micro/nanofiber composites, exercising control over the fiber dimensions and alignment. Unlike conventional spinning-based methods of fiber production, the presented approach is based on micro-transfer molding. It is a parallel processing technique capable of producing fibers with control over both in-plane and out-of-plane geometries, in addition to packing density and layout of the fibers. Collagen has been used as a test polymer to demonstrate the concept. Hollow and solid collagen fibers with various spatial layouts have been fabricated. Produced fibers have widths ranging from 2 µm to 50 µm, and fiber thicknesses ranging from 300 nm to 3 µm. Also, three-dimensionality of the process has been demonstrated by producing in-plane serpentine fibers with designed arc lengths, out-of-plane wavy fibers, fibers with focalized particle encapsulation, and porous fibers with desired periodicity and pore sizes.
The endothelialization of an engineered microvascular network is constrained by the mass transpor... more The endothelialization of an engineered microvascular network is constrained by the mass transport of the endothelial cells through high length-to-depth (l/d) aspect ratio microchannels. This paper presents a deformable, reentrant microvascular scaffold as a microelectromechanical systems (MEMS)-assisted approach for spatially homogeneous endothelial cell seeding of high l/d (>200) aspect ratio microvasculature. Nickel electroplating and micromolding were employed for the fabrication of the polydimethylsiloxane (PDMS) reentrant microvascular scaffold. A 'stretch--seed--seal' ('3S') operation was implemented for uniform incorporation of endothelial cells on the luminal surface of the elastomeric constructs. Confocal microscopy was utilized to establish the uniformity of endothelialization and to demonstrate the feasibility of this strategy.
Vascular disease results in the decreased utility and decreased availability of autologus vascula... more Vascular disease results in the decreased utility and decreased availability of autologus vascular tissue for small diameter (< 6 mm) vessel replacements. While synthetic polymer alternatives to date have failed to meet the performance of autogenous conduits, tissue-engineered replacement vessels represent an ideal solution to this clinical problem. Ongoing progress requires combined approaches from biomaterials science, cell biology, and translational medicine to develop feasible solutions with the requisite mechanical support, a non-fouling surface for blood flow, and tissue regeneration. Over the past two decades interest in blood vessel tissue engineering has soared on a global scale, resulting in the first clinical implants of multiple technologies, steady progress with several other systems, and critical lessons-learned. This review will highlight the current inadequacies of autologus and synthetic grafts, the engineering requirements for implantation of tissue-engineered grafts, and the current status of tissue-engineered blood vessel research.
Proceedings of the Third Annual ACM Bangalore Conference on - COMPUTE '10, 2010
Present computer algebra systems (CAS) are useful for sophisticated users, disregard the availabl... more Present computer algebra systems (CAS) are useful for sophisticated users, disregard the available information on the web and do not provide a social context for solving problems. In this paper we describe how semantic and web 2.0 technology can be used to make CAS as a tool to explore and learn mathematics in addition to giving mathematical problem solving a
Toxicology International
The restorative potential of trans-resveratrol (RV) was investigated in a rat neuronal cell line ... more The restorative potential of trans-resveratrol (RV) was investigated in a rat neuronal cell line (PC12) exposed to organophosphate pesticide-monocrotophos (MCP). RV shows significant protection against MCP-induced alterations in PC12 cells by restoration of oxidative stress-mediated apoptosis and cytotoxicity. RV treatment significantly reduced reactive oxygen species (ROS) production and lipid peroxidation, and also restored glutathione levels and mitochondrial membrane potential, in cells receiving MCP. Restoration of markers such as cytochrome c, Bax, Bcl-2 and caspase-3 also confirms the effectiveness of RV against MCP-induced, mitochondria-mediated apoptosis in PC12 cells. The data identify the protective/restorative potential of RV against MCP-induced neuronal damages by affecting ROS production and the level of antioxidant defence enzymes.
Inhibition mechanisms of tyrosine kinase receptor TrkA and its consequences on apoptosis/ neurona... more Inhibition mechanisms of tyrosine kinase receptor TrkA and its consequences on apoptosis/ neuronal injury were investigated in rat brain neuronal stem cells (rBNSCs) exposed to monocrotophos (MCP, an organophosphate pesticide) and compared with staurosporine. The molecular docking study in GOLD docking program revealed that the staurosporine and MCP followed the similar binding pattern as with the AG-879 (well known TrkA inhibitor) and co-crystallized ligand of TrkA (PDB id: 4AOJ) respectively at the ATP binding domain. This led to the inhibition of TrkA and resulting cascades, though the structures of both the earlier molecules were signi"cantly different from the ATP as well as other well known inhibitors of TrkA. The main cause of MCP mediated TrkA inhibition is considered to be the water mediated Hbond interaction, and strong intraction with Met-592 similar to the co crystallized ligand. In silico data on TrkA inhibition was con"rmed by examining the down regulation of...
Attachment of newly formed crystals to renal epithe- lial cells appears to be a critical step in ... more Attachment of newly formed crystals to renal epithe- lial cells appears to be a critical step in the development of kidney stones. The current study was undertaken to identify potential calcium oxalate monohydrate (COM) crystal-binding proteins on the surface of renal tubular cells. Apical mem- branes were prepared from confluent monolayers of renal epithelial cells (MDCKI line), and COM crystal
Journal of Allergy and Clinical Immunology, 2004
RationaleThe abundance of allergenic Penicillium species has been associated with an increased in... more RationaleThe abundance of allergenic Penicillium species has been associated with an increased incidence of childhood asthma and pulmonary bleeding. Penicillium brevicompactum has been identified as the most prevalent indoor Penicillium species. However, detailed studies on allergen of the ubiquitous Penicillium species are still lacking. For the characterization of allergens of prevalent Penicillium species, molecular cloning of the allergen genes of
European Urology Supplements, 2009
International Journal of Plastics Technology, 2009
Pediatric Surgery International, 1993
Three hundred twenty infants underwent a Ramstedt pyloromyotomy for hypertrophic pyloric stenosis... more Three hundred twenty infants underwent a Ramstedt pyloromyotomy for hypertrophic pyloric stenosis, 182 via a transverse right hypochondrial incision and 138 via a circumumbilical incision. The overall rate of wound infections was 16% for operations performed via the umbilical approach compared with 5.5% for operations via a transverse approach despite a higher use of antibiotic prophylaxis (64% vs 13%). The
Journal of vector borne diseases, 2009
Visceral leishmaniasis, commonly known as kala-azar is endemic in Bihar state, India. Current vec... more Visceral leishmaniasis, commonly known as kala-azar is endemic in Bihar state, India. Current vector control programme in Bihar focuses mainly on spraying the sandfly infested dwellings with DDT. The Government of India in collaboration with WHO has fixed the target 2015 for total elimination of kala-azar. The present study was carried out to see the impact of DDT and improved IEC in the containment of vector density vis-à-vis disease transmission. Before the start of the spraying operations training was imparted to all the medical and paramedical personnel regarding the methods of spraying operations. Pre- and post-sandfly density was monitored in four selected districts. Incidences of kala-azar cases were compared for pre- and post-spray periods. Social acceptability and perceptions of households was collected through questionnaires from 500 randomly selected households in the study districts. House index in three study districts reduced considerably during post-spray when compare...
Tropical gastroenterology : official journal of the Digestive Diseases Foundation
The hepatitis B vaccine is considered to be highly immunogenic and has a good safety profile. In ... more The hepatitis B vaccine is considered to be highly immunogenic and has a good safety profile. In adults, it has a primary non-response rate of 5%-10%. Causes of nonresponse to hepatitis B vaccine include age, sex, obesity smoking. Certain human leucocyte antigen (HLA) phenotypes have been known to be associated with responsiveness to the vaccine, and found to be different in different ethnic groups, such as Caucasians and Orientals. The study was designed to identify the HLA phenotypes that are associated with non-responsiveness to hepatitis B virus (HBV) vaccination amongst a cohort of Indian subjects who agreed to participate in the vaccination programme. The study was offered to 107 volunteers, of whom 102 were found to be negative for HBV markers (hepatitis B surface antigen [HBsAg], anti-HBc, anti-HBe, anti-HBs, hepatitis Be antigen [HBeAg]) . All 102 volunteers were offered recombinant hepatitis B vaccine (20 microg) at 0, 1, and 6 months. Anti-HBs antibody titres were tested ...
Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists, 2008
Some parts of the Indian Himalayan region are covered by established and abandoned tea bushes. Rh... more Some parts of the Indian Himalayan region are covered by established and abandoned tea bushes. Rhizospheric soils of these plants were studied for bacterial dominance and antagonism. Representatives of Bacillus and Pseudomonas genera were found to dominate the rhizosphere of established and abandoned tea bushes, respectively. Amongst the isolated species Bacillus subtilis and Bacillus mycoides appeared to be closely associated with roots of established tea bushes while the rhizosphere of abandoned tea bushes was dominated by Pseudomonas putida. Four isolates of both B. subtilis and P. putida were selected on the basis of maximum antibacterial activity. The bacteriocin-like activity of B. subtilis and P putida strains was detected to be active over a range of temperature 0-50 degrees C and was sensitive to proteolytic enzymes. Incubation of indicator strains with different concentrations of bacteriocin-like substances confirmed their bactericidal activity. Various species of Bacillus...
The New Zealand medical journal, Jan 9, 2011
Veterinary Parasitology, 1999
In a series of three experiments, 64 jirds, Meriones unguiculatus, were infected with 700 infecti... more In a series of three experiments, 64 jirds, Meriones unguiculatus, were infected with 700 infective larvae of Trichostrongylus colubriformis for the study of several biological parameters of this laboratory host-parasite model. In jirds the third stage larvae of T. colubriformis were shown to reach the fourth larval stage by the Day 6 post-infection (PI). By Day 10 PI, all the worms harvested had reached the immature adult stage. All immature adult stages of T. colubriformis developed to sexually mature adult stage by Day 12 PI when the female worms showed developing eggs in their uteri. Developed eggs were observed in the uteri of females on Days 13 and 14 PI. The first eggs of T. colubriformis appeared in the faeces of jirds on Day 13 PI. The peaks of egg production were recorded between Day 21 and Day 31 PI. Immunosuppression of jirds infected with 700 L3, by administration of dexamethasone from Day 57 to Day 94 PI led to increased faecal egg count when compared to untreated controls. All the worms were located in the small intestine. The jirds of dexamethasone treated group harboured higher number of adult worms than those of the untreated group. The number of adult worms was significantly higher in the first part of the small intestine than in the three other similar parts of the small intestine. The coefficient of correlation between the faecal egg count and worm number on the day of necropsy of jirds ranged between r = 0.58 and r = 0.89. Patent infections in jirds were maintained till the end of experiment on Day 100 PI, indicating that in this host and unlike other laboratory hosts, T. colubriformis is responsible for long lasting infections similar to what happens in domestic ruminants. The results of the present study suggest that the jird is a suitable laboratory model to study various aspects of this host-parasite relationship.
This paper reports a template-based technique for the fabrication of polymer micro/nanofiber comp... more This paper reports a template-based technique for the fabrication of polymer micro/nanofiber composites, exercising control over the fiber dimensions and alignment. Unlike conventional spinning-based methods of fiber production, the presented approach is based on micro-transfer molding. It is a parallel processing technique capable of producing fibers with control over both in-plane and out-of-plane geometries, in addition to packing density and layout of the fibers. Collagen has been used as a test polymer to demonstrate the concept. Hollow and solid collagen fibers with various spatial layouts have been fabricated. Produced fibers have widths ranging from 2 µm to 50 µm, and fiber thicknesses ranging from 300 nm to 3 µm. Also, three-dimensionality of the process has been demonstrated by producing in-plane serpentine fibers with designed arc lengths, out-of-plane wavy fibers, fibers with focalized particle encapsulation, and porous fibers with desired periodicity and pore sizes.
The endothelialization of an engineered microvascular network is constrained by the mass transpor... more The endothelialization of an engineered microvascular network is constrained by the mass transport of the endothelial cells through high length-to-depth (l/d) aspect ratio microchannels. This paper presents a deformable, reentrant microvascular scaffold as a microelectromechanical systems (MEMS)-assisted approach for spatially homogeneous endothelial cell seeding of high l/d (>200) aspect ratio microvasculature. Nickel electroplating and micromolding were employed for the fabrication of the polydimethylsiloxane (PDMS) reentrant microvascular scaffold. A 'stretch--seed--seal' ('3S') operation was implemented for uniform incorporation of endothelial cells on the luminal surface of the elastomeric constructs. Confocal microscopy was utilized to establish the uniformity of endothelialization and to demonstrate the feasibility of this strategy.
Vascular disease results in the decreased utility and decreased availability of autologus vascula... more Vascular disease results in the decreased utility and decreased availability of autologus vascular tissue for small diameter (< 6 mm) vessel replacements. While synthetic polymer alternatives to date have failed to meet the performance of autogenous conduits, tissue-engineered replacement vessels represent an ideal solution to this clinical problem. Ongoing progress requires combined approaches from biomaterials science, cell biology, and translational medicine to develop feasible solutions with the requisite mechanical support, a non-fouling surface for blood flow, and tissue regeneration. Over the past two decades interest in blood vessel tissue engineering has soared on a global scale, resulting in the first clinical implants of multiple technologies, steady progress with several other systems, and critical lessons-learned. This review will highlight the current inadequacies of autologus and synthetic grafts, the engineering requirements for implantation of tissue-engineered grafts, and the current status of tissue-engineered blood vessel research.
Proceedings of the Third Annual ACM Bangalore Conference on - COMPUTE '10, 2010
Present computer algebra systems (CAS) are useful for sophisticated users, disregard the availabl... more Present computer algebra systems (CAS) are useful for sophisticated users, disregard the available information on the web and do not provide a social context for solving problems. In this paper we describe how semantic and web 2.0 technology can be used to make CAS as a tool to explore and learn mathematics in addition to giving mathematical problem solving a