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Search Results: 1 - 10 of 139464 matches for " Amrit K. Bansal "
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Immuno-contraceptive potential of sperm specific LDHC4 and SPAM-1 (PH-20) sub units in dog  [PDF]
Ranjna S. Cheema, Nisha Vashishat, Amrit K. Bansal, Gaurav Bakhri, Vinod Kumar Gandotra
Open Journal of Animal Sciences (OJAS) , 2012, DOI: 10.4236/ojas.2012.24037
Abstract: PH-20 (Spam-1) antigen appears to be a bi-functional sperm plasma membrane protein with hyaluronidase activity and its role is related to cumulus penetration as well as zona binding. (LDH-C4) is a key enzyme, distributed specifically in testis and is highly immunogenic, function of which relates to energy metabolism and capacitation of the sperm. Therefore, in this study, we observed the effect of purified native PH-20 and LDH-C4 antigens on sperm function and morphology in dog. Native PH-20 (46, 32 kDa) and LDH-C4 (36, 30, 28) sub units, purified from dog sperm SDS- extracts were used to test as immunocontraceptive candidates in stray dog. Dogs 1, 2, 3, 4, 5/6 and 7/8 were immunized with 46, 32, 36, 30/28, 46/32, 36/30/28 kDa sub units respectively by i/m route and semen was analysed at weekly intervals. High titre of 3200 - 6400 was achieved in all dogs after three boosters. Immune response in treated dogs was confirmed by increase in Ig level in blood serum and reaction of partially purified serum Ig of immunized dogs with respective antigens in double immune diffusion and immunoblots. Immunization of dogs either with individual PH-20/ LDHC sub units or pooled PH-20/LDHC4 sub units showed a significant effect on sperm count, percent motility, viability, HOST and sperm morphology. All the sperm parameters declined to a significant level (p < 0.05) between 45 - 115 DPI and remained low than that of the recommended values for fertile dog semen till 175 DPI. The incubation of spermatozoa in HOS solution in the presence of anti-PH-20 and anti-LDHC Ig significantly reduced the percent HOS positive spermatozoa. A significant decline (p ≤ 0.05) in acrylamide penetration assay was also observed in the presence of anti 46 and 30/28 kDa Ig. Since percent motility, sperm count, HOST and percent normal spermatozoa in immunized dogs were significantly less than that of recommended fertile dog semen, it can be concluded that PH-20 (46/32 kDa) and LDHC4 (36/30/28 kDa) sub units had an immunocontraceptive potential in dog.
Manganese Provides Antioxidant Protection for Sperm Cryopreservation that May Offer New Consideration for Clinical Fertility
Ranjna S. Cheema,Amrit K. Bansal,Gurmail Singh Bilaspuri
Oxidative Medicine and Cellular Longevity , 2009, DOI: 10.4161/oxim.2.3.8804
Abstract: Reactive oxygen species (ROS) are generated by sperm metabolism. While, ROS are required for maturation, capacitation and acrosome reaction, they also modify many peroxidable cellular compounds. There is production of ROS during cryopreservation and frozen spermatozoa are highly sensitive to lipid peroxidation (LPO). Antioxidants exert a protective effect on the plasma membrane of frozen bovine sperm preserving both metabolic activity and cellular viability. Manganese (Mn
Catalytic Hydrolysis of Ethyl Acetate using Cation Exchange Resin (Amberlyst - 15) : A Kinetic Study
K.R. Ayyappan,Amrit P. Toor,Ritu Gupta,Ajay Bansal
Bulletin of Chemical Reaction Engineering & Catalysis , 2009, DOI: 10.9767/bcrec.4.1.22.16-22
Abstract: The kinetic behavior of the heterogeneous hydrolysis of aqueous ethyl acetate over an acidic cation exchange resin, Amberlyst 15, was investigated. The experiments were carried out in a fixed bed reactor at temperatures from 313.15 to 343.15 K and feed molar ratios ,θBo (water to ethyl acetate) from 62.4 to 265.88. The conversion of ethyl acetate was found to increase with increasing reaction temperature. Gas bubble formation was observed at reaction temperature ≥ 343.15K. Absence of mass transfer resistance was verified by conducting the experiments at different catalyst loadings (20 g, 40 g, 64 g) under varied feed flow rates (1 to 25 cm3/min ). The kinetic data was correlated with pseudo first order model and model parameters were determined using Nelder-Mead algorithm for minimizing the objective function. Copyright (c) 2009 by BCREC . All Rights reserved. [Received: 19 July 2009, Revised: 20 August 2009, Accepted: 22 August 2009] [How to Cite: K.R. Ayyappan, A.P. Toor , R. Gupta, A. Bansal, R.K. Wanchoo (2009). Catalytic Hydrolysis of Ethyl Acetate using Cation Exchange Resin (Amberlyst - 15) : A Kinetic Study. Bulletin of Chemical Reaction Engineering and Catalysis, 4(1): 16-22. doi:10.9767/bcrec.4.1.22.16-22] [How to Link/ DOI: http://dx.doi.org/10.9767/bcrec.4.1.22.16-22 ]
Cooperative functions of manganese and thiol redox system against oxidative stress in human spermatozoa
Bansal Amrit,Kaur Anand
Journal of Human Reproductive Sciences , 2009,
Abstract: Aims: In this study, the effects of 0.1 mM Mn 2+ on thiol components (total thiols [TSH], glutathione reduced [GSH], glutathione oxidized [GSSG] and redox ratio [GSH/ GSSG]) have been determined in human spermatozoa. Settings and Design: The subjects of the study were healthy males having more than 75% motility and 80 x 10 6 sperms/mL. Materials and Methods: Fresh semen was suspended in phosphate-buffered saline (PBS) (pH 7.2) and this suspension was divided into eight equal fractions. All fractions, control (containing PBS) and experimental (treated/untreated with [ferrous ascorbate, FeAA - 200 FeSO 4 μM, 1000 μM ascorbic acid, nicotine (0.5 mM) and FeAA + nicotine], supplemented/unsupplemented with Mn 2+ [0.1 mM]), were incubated for 2 h at 378C. These fractions were assessed for determining the thiol components. Statistical Analysis: The data were statistically analyzed by Students " t" test. Results and Conclusions: Ferrous ascorbate, nicotine and ferrous ascorbate + nicotine induced oxidative stress and decreased GSH and redox ratio (GSH/GSSG ratio) but increased the TSH and GSSG levels. Mn 2+ supplementation improved TSH, GSH and redox ratio (GSH/GSSG) but decreased the GSSG level under normal and oxidative stress conditions. Thiol groups serve as defense mechanisms of sperm cells to fight against oxidative stress induced by stress inducers such as ferrous ascorbate, nicotine and their combination (ferrous ascorbate + nicotine). In addition, Mn 2+ supplementation maintains the thiol level by reducing oxidative stress.
Impacts of Oxidative Stress and Antioxidants on Semen Functions
Amrit Kaur Bansal,G. S. Bilaspuri
Veterinary Medicine International , 2011, DOI: 10.4061/2011/686137
Abstract: Oxidative stress (OS) has been considered a major contributory factor to the infertility. Oxidative stress is the result of imbalance between the reactive oxygen species (ROS) and antioxidants in the body which can lead to sperm damage, deformity, and eventually male infertility. Although high concentrations of the ROS cause sperm pathology (ATP depletion) leading to insufficient axonemal phosphorylation, lipid peroxidation, and loss of motility and viability but, many evidences demonstrate that low and controlled concentrations of these ROS play an important role in sperm physiological processes such as capacitation, acrosome reaction, and signaling processes to ensure fertilization. The supplementation of a cryopreservation extender with antioxidant has been shown to provide a cryoprotective effect on mammalian sperm quality. This paper reviews the impacts of oxidative stress and reactive oxygen species on spermatozoa functions, causes of ROS generation, and antioxidative strategies to reduce OS. In addition, we also highlight the emerging concept of utilizing OS as a tool of contraception. 1. Introduction Gametes are susceptible to reactive oxygen species (ROS) attack. When manipulated in vitro during assisted reproductive techniques, these cells run the risk of generating and being exposed to supra-physiological level of ROS [1]. Defective sperm functions are the most prevalent causes of male infertility and a difficult condition to treat [2]. Many environmental, physiological, and genetic factors have been implicated in the poor sperm functions and infertility [3–6]. Thus, it is very important to identify the factors/conditions which affect normal sperm functions. Among various causes, oxidative stress (OS) has been attributed to affect the fertility status and physiology of spermatozoa [7]. The term oxidative stress is generally applied when oxidants outnumber antioxidants [1]. The imbalance between the production of reactive oxygen species (ROS) and a biological systems ability to readily detoxify the reactive intermediates or easily repair the resulting damage is known as oxidative stress [8]. The main destructive aspects of oxidative stress are the production of ROS, which include free radicals and peroxides [9]. The production of ROS by sperm is a normal physiological process, but an imbalance between ROS generation and scavenging activity is detrimental to the sperm and associated with male infertility [10]. Physiological levels of ROS influence and mediate the gametes [11–13] and crucial reproductive processes, such as sperm-oocyte
Antioxidant effect of Mn2+ on capacitation and acrosome reaction of fresh and chilled cattle bull semen
Amrit Kaur Bansal,Ranjna Sundhey Cheema,Vinod Kumar Gandotra
Veterinary Science Development , 2011, DOI: 10.4081/vsd.2011.e18
Abstract: The aim of this paper was to investigate the antioxidant effect of Mn2+ (200 mM) on the sperm capacitation and acrosome reaction of fresh and chilled cattle bull semen. It has been found that Mn2+ supplementation improves (P≤0.05) the motility at 0, 2, 4 and 6 h of incubation. MDA (malondialdehyde), end product of lipid peroxidation, decreases significantly (P≤0.05) with the supplementation of manganese at 0- and 6-hr of incubation both in fresh and chilled semen. Manganese also increases acrosome reaction significantly (P≤0.05) both in fresh and chilled semen at 0, 4 and 6 h of incubation. Therefore, our findings suggest the role of Mn2+supplementation in improving the quality of cattle bull semen by its scavenging property i.e. reduction in the production of reactive oxygen species during its storage at 4°C or incubation at 37°C for capacitation.
Primer on pediatric intracranial ependymomas
Bansal K
Journal of Pediatric Neurosciences , 2006,
Abstract: Aims and Objectives: To review the clinical features and current understanding of the biology and management of pediatric ependymoma, critically analysing the different treatment modalities. Materials and Methods: The MEDLINE database, bibliographies of selected articles, and current English-language texts on the subject were reviewed. A Pubmed search was made with keywords pediatric, intracranial, ependymoma, surgery, chemotherapy, and radiotherapy. Most recent articles and also significant older articles having all above said words were selected and their results were compared in detail. Results: Almost all articles stress the complete or near total resection of the tumor at first surgery followed by radiotherapy in patients older than 3 years of age and chemotherapy in younger children. Conformal radiation therapy (CRT) is a technique which has promising results. Conclusion: Local tumor control is single most important prognostic factor. This is best achieved through gross total tumor resection wherever possible. Radiotherapy should be offered to all patients (>3-years age) with focused dose (CRT) to tumor bed. Chemotherapy with the current agents does not appear to hold much promise. However, it may be useful in the context of providing the surgeon with an opportunity to do further surgery on a tumor that is less vascularized.
Bell′s palsy: Treatment guidelines
Murthy J. M. K.,Saxena Amrit
Annals of Indian Academy of Neurology , 2011,
Abstract:
Bioinformatics in microbial biotechnology – a mini review
Arvind K Bansal
Microbial Cell Factories , 2005, DOI: 10.1186/1475-2859-4-19
Abstract: In the last decade, the revolution in computer technology and memory storage capability has made it possible to model grand challenge problems such as large scale sequencing of genomes and management of large integrated databases over the Internet. This vastly improved computational capability integrated with large-scale miniaturization of biochemical techniques such as PCR, BAC, gel electrophoresis and microarray chips has delivered enormous amount of genomic and proteomic data to the researchers all over the world. This availability of data has led to an explosion of genome and proteome analysis leading to many new discoveries and tools that are not possible in wet-lab experiments.The availability of genomic and proteomics data and improved bioinformatics and biochemical tools has raised the expectation of the humanity to be able to control the genetics by manipulating the existing microbes. The advantages are enormous such as better diagnosis of the diseases through the use of protein biomarkers, protection against diseases using cost effective vaccines [56,73] and rational drug design, improvement in agricultural quality and quantity, and the development of techniques that help us visualize and understand the detailed microbial machine at the systemic level.Since the sequencing of the first complete microbial genome of Haemophilus influenzae in 1995 [29], hundreds of microbial genomes have been sequenced and archived for public research in GenBank ftp://ftp.ncbi.nih.gov/genbank/ webcite through the concerted effort of federal health agencies such as NIH and DOE in USA, EMBL and EBI in Europe, DNA databank of Japan, national laboratories, academic universities, multiple drug development companies such as Celera and non-profit organizations such as TIGR, and companies involved in agricultural industry and bioremediation. The sequencing of human genome [68] and other relevant eukaryotic genomes has raised the expectation of understanding host pathogen interaction f
Truck Drivers And Risk Of STDs Including HIV
Bansal R.K
Indian Journal of Community Medicine , 1995,
Abstract: Research Question: Whether long distance truck drivers are at a higher risk of contracting and transmitting STDs including HIV? Objectives: i) To study the degree of knowledge of HIV and AIDS among long- distance truck drivers. ii) Assess their sexual behaviour including condom use. iii) Explore their prevailing social influences and substance abuse patterns. iv) Explore their treatment seeking bahaviour as regards STDs. v) Deduce their risk of contracting and transmitting STDs including HIV. Study Design: Cross- sectional interview. Setting: Transport Nagar, Indore (M.P) Participants: 210 senior drivers (First drivers) and 210 junior drivers (Second drivers). Study Variables: Extra-Marital sexual intercourse, condom usage, past and present history of STDs, treatment and counseling, substance abuse, social a€" cultural milieu. Outcome Variables: Risk of contraction of STDs. Statistical Analysis: Univariate analysis. Results: 94% of the drivers were totally ignorant about AIDS. 82.9% and 43.8 % of the senior and junior drivers had a history of extra- marital sex and of these only 2 regularly used condoms. 13.8% and 3.3 % of the senior and junior drivers had a past or present history suggestive of STD infection. Alcohol and Opium were regularly used by them. Conclusion: The studied drivers are at a high risk of contracting and transmitting STDs including HIV.
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