vivek kumar

The yield parameters and cost economics of Withania somnifera were studied using dual inoculation of Azotobacter chroococcum and Pseudomonas putida. The experiment was conducted in a randomized block design with 3 replications for 2 consecutive years, along with 2 levels of organic manure, 10 t ha −1 and 20 t ha −1 . Inoculation with the

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

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 ...

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...

Self-assembly of multidomain peptides (MDP) can be tailored to carry payloads that modulate the extracellular environment. Controlled release of growth factors, cytokines, and small-molecule drugs allows for unique control of in vitro and in vivo responses. In this study, we demonstrate this process of ionic cross-linking of peptides using multivalent drugs to create hydrogels for sustained long-term delivery of drugs. Using phosphate, heparin, clodronate, trypan, and suramin, we demonstrate the utility of this strategy. Although all multivalent anions result in good hydrogel formation, demonstrating the generality of this approach, suramin led to the formation of the best hydrogels per unit concentration and was studied in greater detail. Suramin ionically cross-linked MDP into a fibrous meshwork as determined by scanning and transmission electron microscopy. We measured material storage and loss modulus using rheometry and showed a distinct increase in G' and G″ as a function ...

A wavelet optimized finite difference (WOFD) method is presented for adaptively solving a class of singularly perturbed elliptic and parabolic problems. The method is based on an interpolating wavelet transform using polynomial interpolation on dyadic grids. Adaptive feature is performed automatically by thresholding the wavelet coefficients. Numerical examples for elliptic and parabolic problems are provided. The proposed method proves to

Delivery of small molecules and drugs to tissues is a mainstay of several tissue engineering strategies. Next generation treatments focused on localized drug delivery offer a more effective means in dealing with refractory healing when compared to systemic approaches. Here we describe a novel multidomain peptide hydrogel that capitalizes on synthetic peptide chemistry, supramolecular self-assembly and cytokine delivery to tailor biological responses. This material is biomimetic, shows shear stress recovery and offers a nanofibrous matrix that sequesters cytokines. The biphasic pattern of cytokine release results in the spatio-temporal activation of THP-1 monocytes and macrophages. Furthermore, macrophage-material interactions are promoted without generation of a proinflammatory environment. Subcutaneous implantation of injectable scaffolds showed a marked increase in macrophage infiltration and polarization dictated by cytokine loading as early as 3 days, with complete scaffold resorption by day 14. Macrophage interaction and response to the peptide composite facilitated the (i) recruitment of monocytes/macrophages, (ii) sustained residence of immune cells until degradation, and (iii) promotion of a pro-resolution M2 environment. Our results suggest the potential use of this injectable cytokine loaded hydrogel scaffold in a variety of tissue engineering applications.

Background & objectives: 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

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 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 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.

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

Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai 400 085, India Fax: +9122-25505151 E-mail: manmeet@barc.gov.in E-mail: shash@barc.gov.in ... Department of Electronic Science, University of Pune, Pune, 411 ...

Through the use of mechanical reinforcement of collagen matrices, mechanically strong and compliant 3D tissue mimetic scaffolds can be generated that act as scaffolds for soft tissue engineering. Collagen has been widely used for the development of materials for repair, augmentation or replacement of damaged or diseased tissue. Herein we describe a facile method for the layer-by-layer fabrication of robust planar collagen fiber constructs. Collagen gels cast in a phosphate buffer were dried to form dense collagen mats. Subsequent gels were layered and dried atop mats to create multilayer constructs possessing a range of tunable strengths (0.5 - 11 MPa) and stiffness (1 - 115 MPa). Depending on processing conditions and crosslinking of constructs, strain to failure ranged between 9 to 48%. Collagen mats were constructed into hernia patches that prevented hernia recurrence in Wistar rats.

Noting the abundance and importance of collagen as a biomaterial, we have developed a facile method for the production of a dense fibrillar extracellular matrix mimicking collagen-elastin hybrids with tunable mechanical properties. Through the use of excimer-laser technology, we have optimized conditions for the ablation of collagen lamellae without denaturation of protein, maintenance of fibrillar ultrastructure and preservation of native D-periodicity. Strengths of collagen-elastin hybrids ranged from 0.6 to 13 MPa, elongation at break from 9 to 70% and stiffness from 2.9 to 94 MPa, allowing for the design of a wide variety of tissue specific scaffolds. Further, large (centimeter scale) lamellae can be fabricated and embedded with recombinant elastin to generate collagen-elastin hybrids. Exposed collagen in hybrids act as cell adhesive sites for rat mesenchymal stem cells that conform to ablate waveforms. The ability to modulate these features allows for the generation of a class ...

Major limitations of current tissue regeneration approaches using artificial scaffolds are fibrous encapsulation, lack of host cellular infiltration, unwanted immune responses, surface degradation preceding biointegration, and artificial degradation byproducts. Specifically, for scaffolds larger than 200-500 μm, implants must be accompanied by host angiogenesis in order to provide adequate nutrient/waste exchange in the newly forming tissue. In the current work, we design a peptide-based self-assembling nanofibrous hydrogel containing cell-mediated degradation and proangiogenic moieties that specifically address these challenges. This hydrogel can be easily delivered by syringe, is rapidly infiltrated by cells of hematopoietic and mesenchymal origin, and rapidly forms an extremely robust mature vascular network. Scaffolds show no signs of fibrous encapsulation and after 3 weeks are resorbed into the native tissue. These supramolecular assemblies may prove a vital paradigm for tissue...

A 12 year old girl presented with abdomi-nal pain, off and on vomiting and abdomi-nal distension for the last three months. She was afebrile, malnourished and dehy-drated. Abdomen was distended with fee-ble bowel sounds. A scar mark was present on the-rfght side of her abdomen ...

Deceased donor organ programme is still in infancy in India. Assessing deceased donation potential and identifying barriers to its utilization are required to meet needs of patients with organ failure. Over a 6-month period, we identified and followed all presumed brainstem dead patients secondary to brain damage. All patients requiring mechanical ventilation with no signs of respiratory activity and dilated, fixed and nonreacting pupils were presumed to be brainstem dead. All events from suspicion of brainstem death (BSD) to declaration of BSD, approach for organ donation, recovery and transplants were recorded. Subjects were classified as possible, potential and effective donors, and barriers to donation were identified at each step. We identified 80 presumed brainstem dead patients over the study period. The mean age of this population was 35.9 years, and 67.5% were males. When formally asked for consent for organ donation (n = 49), 41 patients' relatives refused. The convers...

Keloid scars are benign well-demarcated tu-mors of skin that extend beyond the original defect and are raised in appearance. They re-sult from excessive collagen deposition, the etiology of which has not been completely elu-cidated.1 Many techniques have been de-scribed ...

... doi :10.1038/npre.2009.4106.1. 0 votes. Homology Modeling of Human α 2A -Adrenoceptor. Jignesh Patel 1 , Gourja G 1 , Vivek Kumar 1 , Yogesh Narkhede 1 , Shikhar Gupta 1 & C. Gopi Mohan 1. Correspondence: (Login to view email address). ...

A reusable strip of oxalate oxidase was prepared by immobilizing covalently partially purified amaranthus leaf oxalate oxidase on to alkyl amine glass beads affixed on a plastic strip. The immobilized enzyme gave a conjugation yield of 48 mg/g support with 87% retention of ...

Detrusor overactivity is a relatively common yet embarrassing symptom complex with significant impact on quality of life. The mainstay of current pharmacological treatment involves the use of muscarinic receptor antagonists, but their therapeutic effectiveness is limited by a combination of limited efficacy and troublesome side effects and has recently been challenged by Herbison et al. Recognition of the limitations of existing therapy has started the search for pharmacotherapeutic agents acting on alternative pathways underlying detrusor overactivity with the intention of improving storage symptoms of urgency, frequency and urge incontinence. Recent research has suggested that several transmitters may modulate bladder storage. However, no agents currently available, acting via mechanisms other than muscarinic receptors have entered clinical practice so far. It is clear that far from being a passive container for urine, the urothelium is a crucial area within the bladder wall and its functions are complex and only now beginning to be appreciated. The release of several neurotransmitters from urothelium in response to distension and its action on receptors on sensory neurons is being increasingly recognized. The role for this afferent stimulation on the micturition reflex is gradually gaining importance in the pathophysiology of detrusor overactivity. In this article, the recent developments in basic science related to the pathogenesis and pharmacological basis for future drug targets for effective management of overactive bladder are discussed.

This paper presents a system that incorporates low-level object tracking and high-level event inference to solve the video event recognition problem. First, the tracking module combines the results of block tracking and human tracking to provide the trajectory as well as the basic type (human or non-human)of each detected object. The trajectories are then mapped to 3D world coordinates, given

... Destructive ocular myiasis in a non-compromised host. Indian J Ophthalmol. 1990;38:184–6. [PubMed]. 4. Radmanesh M, Khataminia G, Eliasi P, Korai MK, Ebrahimi A. Chrysomyia bezziana-infested basal cell carcinoma destroying the eye. Int J Dermatol. 2000;39:455–62. ...

Circadian rhythms in mammals are generated by a transcriptional negative feedback loop that is driven primarily by oscillations of PER and CRY, which inhibit their own transcriptional activators, CLOCK and BMAL1. Current models posit that CRY is the dominant repressor, while PER may play an accessory role. In this study, however, constitutive expression of PER, and not CRY1, severely disrupted the clock in fibroblasts and liver. Furthermore, constitutive expression of PER2 in the brain and SCN of transgenic mice caused a complete loss of behavioral circadian rhythms in a conditional and reversible manner. These results demonstrate that rhythmic levels of PER2, rather than CRY1, are critical for circadian oscillations in cells and in the intact organism. Our biochemical evidence supports an elegant mechanism for the disparity: PER2 directly and rhythmically binds to CLOCK:BMAL1, while CRY only interacts indirectly; PER2 bridges CRY and CLOCK:BMAL1 to drive the circadian negative feedback loop.