120 results on '"Kanwar SS"'
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2. Phytochemical Studies and In Vitro Evaluation of Antioxidant & Antihyperglycemic Activities of Actinidia deliciosa (A. Chev.) C.F. Liang & A.R. Ferguson (Kiwifruit)
- Author
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Dhiman Vk, Kanwar Ss, and Chauhan
- Subjects
Actinidia deliciosa ,Antioxidant ,Traditional medicine ,Phytochemical ,medicine.medical_treatment ,medicine ,Biology ,biology.organism_classification ,In vitro - Published
- 2020
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3. Phyto-molecules for Kidney Stones Treatment and Management
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Gupta S and Kanwar Ss
- Subjects
medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Urinary system ,Urology ,04 agricultural and veterinary sciences ,General Medicine ,medicine.disease ,040401 food science ,Extracorporeal shock wave lithotripsy ,Clinical trial ,Fluid intake ,0404 agricultural biotechnology ,Pharmacotherapy ,Genetic predisposition ,medicine ,Kidney stones ,business ,Hydronephrosis - Abstract
It has been centuries since humans are being affected by kidney stones or urolithiasis. In the past decade, in rural and the urban sectors, kidney stone cases are rising at an alarming rate having a high relapse rate. The rate and prevalence of urolithiasis has been attributed to a number of factors such as age, fluid intake, infections of the urinary tract, climatic conditions sex, genetic predisposition, ethnicity as well as diet. Kidney stones may cause extreme pain and blockage of urine flow, urinary tract infection, hydronephrosis and severe bleeding which necessitates the use of surgery in some cases to remove or break the stones. Although a number of treatments for kidney stones are available which include extracorporeal shock wave lithotripsy (ESWL) and drug therapy but the expensive nature of these therapies and the severe side effects caused by exposure to these shock waves such as acute renal injury, decreased renal function and increased stone recurrence limit their use. As proposed by several in vivo and in vitro studies and clinical trials, using phyto-molecules in the treatment and management of kidney stones has emerged as a novel option. The following study discuses about the various plants, their chemical constituents involved along with their mechanism of action that can be used for the treatment of kidney stones.
- Published
- 2018
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4. Ribonuclease as Anticancer Therapeutics
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Kanwar Ss and Kumar R
- Subjects
biology ,RNase P ,media_common.quotation_subject ,Ribonuclease inhibitor ,RNA ,Endocytosis ,Molecular biology ,Cell biology ,Cancer cell ,biology.protein ,Ribonuclease ,Internalization ,Cytotoxicity ,media_common - Abstract
Ribonucleases (RNases) are small molecules which are highly cytotoxic in nature. They catalyse the degradation of RNA into smaller molecules rapidly in an unprotected environment. The cytotoxic properties of RNases include degradation of RNA leading to blockage of protein synthesis in malignant cells and inducing the apoptosis response. Cytotoxicity of RNases is determined by catalytic activity, stability, non-selective nature of inhibitors, positive charge on molecule and internalization. Onconase, BS-RNase and other RNases exert cytotoxic activity on cancer cells selectively by involving different cellular pathways and/ or enhance the cytotoxicity by mutation. A general mechanism of the cytotoxic activity of RNases includes the interaction of the enzyme with the cellular membrane by non-specific interactions mediated by Coulombic forces, internalization by endocytosis, translocation to the cytosol, degradation of ribonucleic acid and subsequent cell death by activation of caspase-dependent mechanisms, low molecular weight compounds or alteration in protein and NF-κB signal pathway. But still it is unclear that which of these mechanisms is most potent, common and causes cell death in cancerous cells. The problem related to ribonuclease inhibitor (RI) has not fully elucidated. This article looks at the cellular pathways of RNases and mechanism of their cytotoxicity towards the malignant cells which makes RNase as a strong candidate to be considered as chemotherapeutic or antitumor drug. Some of the prominent approaches to exploit RNase molecule as an anticancer therapeutic agent have been discussed.
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- 2017
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5. Comparative Evaluation of Commercial and Indigenous Bacterial Isolates for Antigenotoxic Potential
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Delia Kanwar SS
- Published
- 2017
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6. Effect of non-steroidal anti-inflammatory drugs and the pro-carcinogen 1,2 dimethylhydrazine on the rat intestinal membrane structure and function.
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Mittal N, Kanwar SS, Sanyal SN, Mittal, N, Kanwar, S Singh, and Sanyal, S Nath
- Abstract
The present study was designed to evaluate the effects of three non-steroidal anti-inflammatory drugs (NSAIDs) with varying cycloxygenase selectivities on the small intestinal biochemical composition, function and histology during 1, 2-dimethylhydrazine (DMH) administration. Sprague Dawley male rats were divided into five different groups viz: Group 1 (control, vehicle treated), Group 2 (DMH-treated, 30 mg/kg body weight/week in 1 mM EDTA-saline, subcutaneously), Group 3 (DMH + aspirin-60 mg/kg body weight), Group 4 (DMH + celecoxib-6 mg/kg body weight), Group 5 (DMH + etoricoxib-0.64 mg/kg body weight). After six weeks of treatment, brush border membrane was isolated from the jejunum segment of all the groups and changes in the associated enzymes such as sucrase, lactase, maltase, alkaline phosphatase, membrane lipid composition, fluorescence polarizations of diphenylhexatriene, pyrene excimer formation, histological changes and surface characteristics were studied. The results indicated a significant alteration in the enzyme activity as well as changes in the structure and function of the intestine in the presence of the pro-carcinogen, DMH, which suggests the possible chemopreventive efficacy of NSAIDs against the intestinal cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2008
7. Direct and antibody dependent cell mediated cytotoxicity against Giardia lamblia by splenic and intestinal lymphoid cells in mice
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B.N.S. Walia, Kanwar Ss, R. C. Mahajan, and Nirmal Kumar Ganguly
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Cytotoxicity, Immunologic ,Giardiasis ,Antibody-dependent cell-mediated cytotoxicity ,Lamina propria ,Giardia ,Lymphocyte ,Antibody-Dependent Cell Cytotoxicity ,Gastroenterology ,Biology ,medicine.disease_cause ,Epithelium ,Microbiology ,Mice ,medicine.anatomical_structure ,medicine ,Animals ,Cytotoxic T cell ,Intraepithelial lymphocyte ,Giardia lamblia ,Lymphocytes ,Intestinal Mucosa ,Cytotoxicity ,Spleen ,Research Article - Abstract
Direct cytotoxicity and antibody dependent cell mediated cytotoxicity against Giardia lamblia trophozoites exhibited by splenic, intraepithelial and lamina propria lymphocyte populations isolated from G lamblia infected mice were studied. Different patterns of cytotoxicity were found. Intraepithelial lymphocytes showed a direct cytotoxic activity of 20.6 +/- 5.6% before infection. It was significantly higher on the 20th (p less than 0.01) and 30th (p less than 0.05) day postinfection. Lamina propria lymphocytes showed a significantly augmented level of both direct cytotoxicity and antibody dependent cell mediated cytotoxicity on the 20th and 30th postinfection days. Direct cytotoxicity by splenic lymphocytes remained unchanged during infection but antibody dependent cell mediated cytotoxicity was significantly increased.
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- 1986
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8. The macrophages as an effector cell in Giardia lamblia infections
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B. N. S. Walia, Mahajan Rc, Kanwar Ss, and Nirmal Kumar Ganguly
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Cytotoxicity, Immunologic ,Giardiasis ,Microbiology (medical) ,medicine.medical_specialty ,Immunology ,medicine.disease_cause ,Effector cell ,Microbiology ,Peak response ,Mice ,Medical microbiology ,medicine ,Animals ,Humans ,Immunology and Allergy ,Cytotoxic T cell ,Giardia lamblia ,biology ,Giardia ,Macrophages ,Antibody-Dependent Cell Cytotoxicity ,General Medicine ,biology.organism_classification ,Virology ,Post infection - Abstract
Direct and antibody-dependent, cell-mediated cytotoxic responses exhibited against Giardia lamblia trophozoites by peritoneal macrophages of infected animals were studied. On first exposure, the infection persisted for 30 days and peak cytotoxic responses were noticed on the 20th day post infection. In reinfected animals, peak response was on 10th day and these animals were capable of clearing the infection much faster compared with animals infected for the first time. Macrophages in Giardia infection, therefore, seem to play an important role in providing resistance to infected animals as evident from significant augmentation of their cytotoxic responses in the infected animals.
- Published
- 1987
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9. Specific secretory IgA in the milk of Giardia lamblia-infected and uninfected women
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B. N. S. Walia, N. Nayak, Mahajan Rc, Kanwar Ss, Vanita Wahi, and Nirmal Kumar Ganguly
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Immunoglobulin A ,Adult ,Giardiasis ,medicine.disease_cause ,Microbiology ,Feces ,fluids and secretions ,parasitic diseases ,medicine ,Immunology and Allergy ,Giardia lamblia ,Humans ,Secretory IgA ,biology ,Milk, Human ,Giardia ,Infant ,Immunoglobulin A.secretory ,biology.organism_classification ,Infection rate ,Titer ,Infectious Diseases ,Breast Feeding ,Immunology ,Immunoglobulin A, Secretory ,biology.protein ,Female ,Antibody ,Immunity, Maternally-Acquired - Abstract
We measured the levels of specific secretory IgA in human milk by using an enzyme-linked immunosorbent assay. We studied Giardia lamblia-infected and -uninfected mothers to determine the role of such IgA in providing protection against Giardia infection to their children. Titers of specific secretory IgA in the milk of infected mothers were significantly higher than were those of uninfected mothers (P less than .01). Only 16% of infants of mothers with high titers of antibodies (higher OD) in their milk were infected with Giardia. In contrast, there was an infection rate of 63.0% in infants of mothers with low titers of antibody in their milk (lower OD; P less than .01).
- Published
- 1987
10. Synergistic exploration of Surfactin-capped silver nanoparticles: bioinformatics insights, antibacterial potency, and anticancer activity.
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Chauhan V, Pandey A, Mahajan G, Dhiman V, and Kanwar SS
- Abstract
Surfactin lipopeptides (LPs) are a compelling class of biosurfactants with notable antimicrobial and anticancer properties. This study presents a novel approach by integrating bioinformatics tools to assess the drug potential of Surfactin, specifically focusing on its antibacterial, antifungal activities, and cancer cell-line toxicity. Silver nanoparticles (AgNPs) were synthesized using Surfactin, a biosurfactant derived from Bacillus subtilis KLP2016, as a capping agent, both in the presence and absence of Surfactin, to evaluate its impact on nanoparticle stability and bioactivity. The Surfactin-capped AgNPs demonstrated enhanced stability, uniformity, and antimicrobial efficacy, confirmed through UV-VIS spectroscopy, FE-SEM, and X-ray diffraction analysis. The bioinformatics approach, including ADMET and PASS analysis, revealed the potential of Surfactin as a potent antimicrobial and anticancer agent. In addition, molecular docking studies further validated the interaction of Surfactin with key microbial cell-wall enzymes and proteins, underscoring its therapeutic potential. These findings suggest that Surfactin-stabilized AgNPs, combined with bioinformatic predictions, could pave the way for innovative antimicrobial and anticancer therapies., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© King Abdulaziz City for Science and Technology 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)
- Published
- 2025
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11. Molecular characterization and in silico analysis of oxalate decarboxylase of Pseudomonas sp. OXDC12.
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Gupta S and Kanwar SS
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- Histidine, Ligands, Ions, Pseudomonas metabolism, Carboxy-Lyases
- Abstract
Oxalate decarboxylase (OxDC) is a Mn-dependent hexameric enzyme that is highly important in management of calcium oxalate mediated nephrolithiasis. The present study reported the production and purification of OxDC from Pseudomonas sp. OXDC12 up to 45.3-fold with an overall yield of 7%. The purified OxDC displayed a single band of approximately 40 kDa on SDS-PAGE and 240 kDa on Native-PAGE suggesting it to be a hexameric enzyme. The purified OxDC displayed an optimum activity at 26 °C and pH 4.5 in the presence of substrate sodium oxalate (30 mg/mL) with a K
m and Vmax value of 43.9 mM and 8.9 µmol/min, respectively and an activation energy of 52.49 kJ/mol. The enzyme activity was significantly enhanced by adding o -phenylenediamine to the reaction mixture. OxDC exhibited a very low 17 haemolytic activity which suggested a relatively safer therapeutic aspect of the tested OxDC. The structure prediction studies of the OxDC revealed a tertiary structure with α/β chains that formed the β barrel structure, typical of all cupin domains. The Ramachandran plot produced by PROCHECK shows that 90.5% of the residues are in the most favoured region and hence the OxDC model produced was a good one. Docking studies revealed the binding of the metal ions and ligands to cluster of three histidine residues in the N terminal domain that formed the active site pocket of the enzyme. It was suggested that the histidine coordinated Mn2+ ion was critical for substrate recognition and binding and was also directly involved in OxDC catalyses.highlightsOxalate decarboxylase (OxDC) was successfully purified from Pseudomonas sp. OXDC12 up-to 45.3-fold.The Km and Vmax values of the purified OxDC were calculated as 43.9 mM and 8.9 µmol/min, respectively.Genre analysis and structure prediction studies revealed the presence of β barrel structure typical of all cupin domains. The model exhibited a bi-cupin domain that forms the dimer of the homo-hexameric OxDC.Docking experiments revealed that the cluster of three HIS residues in the N terminal domain of the tested enzyme formed the active site pocket for binding of Mn as well as the ligands.Communicated by Ramaswamy H. Sarma.- Published
- 2023
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12. Biomarkers in renal cell carcinoma and their targeted therapies: a review.
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Gupta S and Kanwar SS
- Abstract
Renal cell carcinoma (RCC) is one of the most life-threatening urinary malignancies displaying poor response to radiotherapy and chemotherapy. Although in the recent past there have been tremendous advancements in using targeted therapies for RCC, despite that it remains the most lethal urogenital cancer with a 5-year survival rate of roughly 76%. Timely diagnosis is still the key to prevent the progression of RCC into metastatic stages as well as to treat it. But due to the lack of definitive and specific diagnostic biomarkers for RCC and its asymptomatic nature in its early stages, it becomes very difficult to diagnose it. Reliable and distinct molecular markers can not only refine the diagnosis but also classifies the tumors into thier sub-types which can escort subsequent management and possible treatment for patients. Potential biomarkers can permit a greater degree of stratification of patients affected by RCC and help tailor novel targeted therapies. The review summarizes the most promising epigenetic [DNA methylation, microRNA (miRNA; miR), and long noncoding RNA (lncRNA)] and protein biomarkers that have been known to be specifically involved in diagnosis, cancer progression, and metastasis of RCC, thereby highlighting their utilization as non-invasive molecular markers in RCC. Also, the rationale and development of novel molecular targeted drugs and immunotherapy drugs [such as tyrosine kinase inhibitors and immune checkpoint inhibitors (ICIs)] as potential RCC therapeutics along with the proposed implication of these biomarkers in predicting response to targeted therapies will be discussed., Competing Interests: The authors declare that there are no conflicts of interest., (© The Author(s) 2023.)
- Published
- 2023
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13. Screening, characterization and anti-cancer application of purified intracellular MGL.
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Sharma B, Devi S, Kumar R, and Kanwar SS
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- Animals, Humans, Mice, Neoplasms pathology
- Abstract
L-methionine-γ-lyase (MGL) producing bacterial isolates were screened from soil samples that further characterized as 'Klebsiella oxytoca BLM-1' by biochemical and 16S rDNA sequencing. Intracellular MGL obtained from K. oxytoca BLM-1 by sonication was purified by Octyl-Sepharose and Sephadex G-200 column chromatography. MALDI-TOF-MS analysis of protein band (Mr ~ 63 kDa) confirmed the PLP-dependence and structural similarity with MGL enzyme. Purified MGL (1.1 μg) exhibited the maximum activity in potassium phosphate buffer (80 mM; with L-met 20 mM pH 7.0) at 37 °C. That further enhanced in the presence of NaCl (2 mM), Tween-80 (1.0 %; v/v) and EDTA (5 mM). K
m and Vmax for purified MGL by using L-met as substrate was found to be 5.32 mM and 0.386 U/mL/min. The purified MGL showed PLP dependence and the half-life was 365.59 min. The MGL was effective against breast cancer (MCF7), gastric adenocarcinoma and human glioblastoma (U87MG) cancer cell lines with IC50 values of purified MGL 0.041 U/mL, 0.008 U/mL and 0.009 U/mL, respectively. The U87MG, greatly affected by MGL treatment, when cultured in DMEM medium (10 mL) with PLP, homocysteine and 10 % FCS as compared to control/untransformed mouse spleen cells., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
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14. An Insight in Developing Carrier-Free Immobilized Enzymes.
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Chauhan V, Kaushal D, Dhiman VK, Kanwar SS, Singh D, Dhiman VK, and Pandey H
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Enzymes play vital roles in all organisms. The enzymatic process is progressively at its peak, mainly for producing biochemical products with a higher value. The immobilization of enzymes can sometimes tremendously improve the outcome of biocatalytic processes, making the product(s) relatively pure and economical. Carrier-free immobilized enzymes can increase the yield of the product and the stability of the enzyme in biocatalysis. Immobilized enzymes are easier to purify. Due to these varied advantages, researchers are tempted to explore carrier-free methods used for the immobilization of enzymes. In this review article, we have discussed various aspects of enzyme immobilization, approaches followed to design a process used for immobilization of an enzyme and the advantages and disadvantages of various common processes used for enzyme immobilization., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Chauhan, Kaushal, Dhiman, Kanwar, Singh, Dhiman and Pandey.)
- Published
- 2022
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15. Combination of classical and statistical approaches to enhance the fermentation conditions and increase the yield of Lipopeptide(s) by Pseudomonas sp. OXDC12: its partial purification and determining antifungal property.
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Chauhan V, Dhiman V, and Kanwar SS
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Around 200 different lipopeptides (LPs) have been identified to date, most of which are produced via Bacillus and Pseudomonas species. The clinical nature of the lipopeptide (LP) has led to a big surge in its research. They show antimicrobial and antitumor activities due to which mass-scale production and purification of LPs are beneficial. Response surface methodology (RSM) approach has emerged as an alternative in the field of computational biology for optimizing the reaction parameters using statistical models. In the present study, Pseudomonas sp. strain OXDC12 was used for production and partial purification of LPs using Thin Layer Chromatography (TLC). The main goal of the study was to increase the overall yield of LPs by optimizing the different variables in the fermentation broth. This was achieved using a combination of one factor at a time (OFAT) and response surface methodology (RSM) approaches. OFAT technique was used to optimize the necessary parameters and was followed by the creation of statistical models (RSM) to optimize the remaining variables. Maximum mycelial growth inhibition (%) against the fungus Mucor sp. was 61.3% for LP. Overall, the combination of both OFAT and RSM helped in increasing the LPs yield by 3 folds from 367mg/L to 1169mg/L., Competing Interests: CONFLICT OF INTEREST: Authors declare that they have no conflict of interest with each other or with the parent institute., (Copyright © 2021 The Author(s).)
- Published
- 2021
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16. Hepato-protective role of chemo-preventive probiotics during DMH-induced CRC in rats.
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Walia S, Kamal R, Kanwar SS, and Dhawan DK
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- Animals, Colorectal Neoplasms metabolism, Colorectal Neoplasms microbiology, Female, Gene Expression Regulation, Neoplastic, Neoplasm Proteins biosynthesis, Rats, Rats, Sprague-Dawley, Colorectal Neoplasms prevention & control, Lactobacillus plantarum, Lacticaseibacillus rhamnosus, Probiotics pharmacology
- Abstract
The aim of the study was to assess the hepatotoxicity, and therefore pharmacological safety of probiotics Lactobacillus plantarum (AdF10) and Lactobacillus rhamnosus GG (LGG) for potential use in colorectal cancer (CRC) prevention. Thirty-six female Sprague Dawley (SD) rats were divided into six groups: normal control, AdF10-treated, LGG-treated, 1,2-Dimethyl hydrazine (DMH)-treated, AdF10 + DMH-treated, and LGG + DMH-treated groups. Antioxidant enzyme activity, lipid proxidation, and liver function were assessed. Administration of probiotics in both AdF10 + DMH-treated and LGG + DMH-treated groups downregulated DMH induced a rise in lipid peroxide (LPO), glutathione reductase (GR) activity, and increased the diminished glutathione reduced (GSH) content and catalase (CAT), glutathione-transferase (GST), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities. DMH-treated rats receiving the probiotic treatment suffered less liver damage when compared with rats that did not receive probiotics. In conclusion, the study identifies the use of probiotics as an effective and nontoxic chemo-preventive interventional in CRC., (© 2021 Wiley Periodicals LLC.)
- Published
- 2021
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17. Lipopeptide(s) associated with human microbiome as potent cancer drug.
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Chauhan V and Kanwar SS
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- Animals, Humans, Neoplasms microbiology, Antineoplastic Agents administration & dosage, Gastrointestinal Microbiome, Lipopeptides administration & dosage, Neoplasms drug therapy
- Abstract
Human microbiota comprises of trillions of microbes which have evolved with and continued to live on/ within their human hosts. Different environmental factors and diet have a large impact upon human microbiota population. These microorganisms live in synergy with their hosts and are beneficial to the host in many different ways. Many microorganisms help to fight against human diseases. Cancer is one such diseases which effects a large human population often leading to death. Cancer is also one of the most fatal human diseases killing millions of people world-wide every year. Though many treatment procedures are available but none is 100 % effective in curing cancer. In this review, we seek to understand the role of human microbiota in cancer treatment. Lipopeptide(s) (LPs) produced by different microorganisms can act as efficient drug(s) against cancer. LPs are low molecular weight lipo-proteins that are also known for their anti-cancer activities. As human microbiota belongs to an environment within the host body, a drug prepared using these microorganisms will be easily accepted by the body. This novel approach of using LPs produced by human microbiota can be considered for the much needed change in cancer treatment. Therefore, it is proposed that research should focus on the host-microbe interaction which could pave the way in understanding role played by these microorganisms in cancer treatment., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2021
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18. An Unusual Case of Lung Consolidation: Thinking Beyond Pneumonia.
- Author
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Kanwar SS, Downey SA, and Tandon YK
- Subjects
- Adult, Anti-Bacterial Agents therapeutic use, Bacterial Infections drug therapy, Bronchopulmonary Sequestration pathology, Bronchopulmonary Sequestration therapy, Humans, Ligation, Lung Diseases microbiology, Lung Diseases pathology, Male, Piperacillin, Tazobactam Drug Combination therapeutic use, Thoracoscopy, Bacterial Infections diagnosis, Bacterial Infections pathology, Bronchopulmonary Sequestration complications, Bronchopulmonary Sequestration diagnosis, Lung Diseases diagnosis
- Published
- 2021
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19. Biodiversity of meatborne Listeria spp. in Himachal Pradesh and their interaction with indigenous probiotics.
- Author
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Sharma A, Kanwar SS, and Thakur SD
- Abstract
This study determined the anti-listerial activity of indigenous probiotics from traditional fermented foods of Western Himalaya against meat borne Listera monocytogens isolates from Himachal Pradesh. One hundred samples of meat and meat products like chicken (n = 25), chevon (goat meat, n = 20), fish (n = 20) and pork (n = 30) were collected and were analyzed for the presence of Listeria spp. by recommended culture and biochemical methods. L. monocytogens isolates were confirmed by PCR targeting the virulence gene hlyA (haemolysin A) and by16S rRNA sequencing. Anti-listerial activity of probiotic bacteria isolated from indigenous fermented foods of Himachal Pradesh was determined by well diffusion method using Lactobacillus rhamnosus GG (ATCC 53103) as the reference strain. Five percent of tested samples were found positive for L. monocytogens with incidence of 8.0% in chicken (2/25), 10.0% in fish (2/20) and 4.0% in chevon meat (1/25). None of the tested pork samples were found contaminated with L. monocytogenes . Among 11 indigenous probiotics used in this study, highest antagonistic activity was exhibited by Lactobacillus plantarum (ADF 10) and Enterococcus faecium (ADF1) which was equivalent to the reference strain., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Association of Food Scientists & Technologists (India) 2020.)
- Published
- 2021
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20. Purification and identification of a surfactin biosurfactant and engine oil degradation by Bacillus velezensis KLP2016.
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Meena KR, Dhiman R, Singh K, Kumar S, Sharma A, Kanwar SS, Mondal R, Das S, Franco OL, and Mandal AK
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- Bacillus growth & development, Biodegradation, Environmental, Carbon Dioxide chemistry, Chromatography, Gel, Emulsions, Gas Chromatography-Mass Spectrometry, Hydrocarbons analysis, Micelles, Reference Standards, Surface Tension, Bacillus metabolism, Lipopeptides isolation & purification, Petroleum Pollution, Surface-Active Agents isolation & purification
- Abstract
Engine oil used in automobiles is a threat to soil and water due to the recalcitrant properties of its hydrocarbons. It pollutes surrounding environment which affects both flora and fauna. Microbes can degrade hydrocarbons containing engine oil and utilize it as a substrate for their growth. Our results demonstrated that cell-free broth of Bacillus velezensis KLP2016 (Gram + ve, endospore forming; Accession number KY214239) recorded an emulsification index (E
24 %) from 52.3% to 65.7% against different organic solvents, such as benzene, pentane, cyclohexane, xylene, n-hexane, toluene and engine oil. The surface tension of the cell-free broth of B. velezensis grown in Luria-Bertani broth at 35 °C decreased from 55 to 40 mN m-1 at critical micelle concentration 17.2 µg/mL. The active biosurfactant molecule of cell-free broth of Bacillus velezensis KLP2016 was purified by Dietheylaminoethyl-cellulose and size exclusion chromatography, followed by HPLC (RT = 1.130), UV-vis spectrophotometry (210 nm) and thin layer chromatography (Rf = 0.90). The molecular weight of purified biosurfactant was found to be ~ 1.0 kDa, based on Electron Spray Ionization-MS. A concentration of 1980 × 10-2 parts per million of CO2 was trapped in a KOH solution after 15 days of incubation in Luria-Bertani broth containing 1% engine oil. Our results suggest that bacterium Bacillus velezensis KLP2016 may promise a new dimension to solving the engine oil pollution problem in near future.- Published
- 2021
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21. Purification, characterization and cytotoxic properties of a bacterial RNase.
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Kumar R, Katwal S, Sharma B, Sharma A, Puri S, Kamboj N, and Kanwar SS
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- A549 Cells, Bacterial Proteins metabolism, Bacterial Proteins toxicity, Caco-2 Cells, Cell Proliferation drug effects, Cells, Cultured, Enzyme Stability, Erythrocytes drug effects, HEK293 Cells, Hemolysis, Hep G2 Cells, Humans, MCF-7 Cells, Ribonucleases metabolism, Ribonucleases toxicity, Bacillus enzymology, Bacterial Proteins chemistry, Ribonucleases chemistry
- Abstract
An RNase produced by Bacillus safensis RB-5 was purified up to 22.32-fold by successive techniques of salting out, DEAE-anion exchange and gel permeation (Sephadex G-100) chromatography techniques with a yield of 2.27%. The purified RNase possessed a single band in SDS-PAGE (Mr ~ 60 kDa). The purified RNase showed optimal activity at temperature of 37 °C and pH 7.5 in the presence of substrate (Yeast RNA) and Mg
2+ ions. The RNase activity was strongly inhibited by Hg2+ and mildly by Fe2+ , Ba2+ and Zn2+ ions. Its half-life was found to be 8 h at 37 °C. The RNase kinetics study showed Km and Vmax value of 0.3 mM and 9.2 μmol/mg/min, respectively. The purified RNase also showed cytotoxic and antiproliferative activities towards a few transformed cell lines. The purified RNase (IC50 0.035 U/mL) effectively inhibited RD and Hep-2C cells proliferation & migration, while sparing HEK 293 cells. The purified RNase was cytotoxic as well as effective degrader of the RNA of transformed RD cells at low concentration. Moreover, the purified RNase of B. safensis RB-5 was found to possess a little hemolytic activity towards human RBCs., Competing Interests: Declaration of competing interest The authors declare that they do not have any conflict of interest among themselves or with the host institution., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2021
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22. Utility of Silane-Modified Magnesium-Based Magnetic Nanoparticles for Efficient Immobilization of Bacillus thermoamylovorans Lipase.
- Author
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Rana S, Sharma A, Kumar A, Kanwar SS, and Singh M
- Subjects
- Enzymes, Immobilized metabolism, Fatty Acids metabolism, Kinetics, Lipase metabolism, Temperature, Bacillus enzymology, Enzymes, Immobilized chemistry, Lipase chemistry, Magnesium chemistry, Magnets chemistry, Nanoparticles chemistry, Silanes chemistry
- Abstract
Enzymes and protein's immobilization on magnetic nano supports is emerging as a promising candidate in the food, medical field, and areas of environmental studies. This work presents a study on purified Bacillus thermoamylovorans lipase (BTL) by utilizing tetraethoxysilane (TEOS)-modified magnesium nano ferrite (MgNF) of 20 nm size. Its structural and morphological studies were investigated by powder X-ray diffractometry, high-resolution transmission electron microscopy, etc. Binding of BTL with MgNF was supported by using Fourier transform infrared spectroscopy. Magnetic behavior was examined by the vibrational sample magnetometer and Mössbauer spectrometer graphs. The enzymatic activity of BTL before and after immobilization was studied at different temperatures and reaction time. As per the Lineweaver-Burk plot, immobilized lipase has more biological affinity for fatty acids in comparison to the free lipase, and K
max values of immobilized and free BTL were computed as 6.6 and 7.5 mM respectively, with excellent reusability(> 50%) even till 13 consecutive assay runs. Graphical Abstract.- Published
- 2020
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23. Phosphatidylserine: A cancer cell targeting biomarker.
- Author
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Sharma B and Kanwar SS
- Subjects
- Biomarkers, Tumor antagonists & inhibitors, Cell Membrane drug effects, Humans, Models, Biological, Molecular Targeted Therapy trends, Neoplasms diagnosis, Neoplasms drug therapy, Phosphatidylserines antagonists & inhibitors, Protein Binding, Saposins metabolism, Saposins therapeutic use, Biomarkers, Tumor metabolism, Cell Membrane metabolism, Molecular Targeted Therapy methods, Neoplasms metabolism, Phosphatidylserines metabolism
- Abstract
Cancer is a leading cause of mortality and morbidity globally. Many prominent cancer-associated molecules have been identified over the recent years which include EGFR, CD44, TGFbRII, HER2, miR-497, NMP22, BTA, Fibrin/FDP etc. These biomarkers are often used for screening, detection, diagnosis, prognosis, prediction and monitoring of cancer development. Phosphatidylserine (PS) is an essential component in all human cells which is present on the inner leaflet of the cell membrane. The oxidative stress causes exposure of PS on the surface of the vascular endothelium in the cancer cells (lung, breast, pancreatic, bladder, skin, brain metastasis, rectal adenocarcinoma etc.) but not on the normal cells. The external PS is regulated by calcium-dependent flippase activity. Cancer cell lines with high surface PS have low flippase activity and high intracellular calcium content. Human Annexin-V, PS targeting antibodies (PGN635 and bavituximab and mch1N11), lysosomal protein, phospholipid Saposin C dioleoylphosphatidylserine (SapC-DOPS), peptide-peptoid hybrid PPS1, PS-binding 14-mer peptide (PSBP-6) and hexapeptide (E3) have been reported to target PS present on cancer cell surface. High expression of CD47 inhibits tumor cell phagocytosis by macrophages. The PS cancer biomarker has also been used to target the drugs to cancer cells specifically without affecting other healthy cells. Currently, the fusion protein (FP) consisting of L-methionase linked to human Annexin-V has been reported to target the cancer cells. The FP catalyzes the conversion of non-toxic prodrug selenomethionine into toxic methyl selenol which thus also prevents the methionine (essential amino acid) supplementation to the cancer cells., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
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24. Chemoprevention by Probiotics During 1,2-Dimethylhydrazine-Induced Colon Carcinogenesis in Rats.
- Author
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Walia S, Kamal R, Dhawan DK, and Kanwar SS
- Subjects
- Animals, Apoptosis, Colonic Neoplasms etiology, Disease Models, Animal, Female, Lactobacillus plantarum, Lacticaseibacillus rhamnosus, Oxidative Stress, Rats, Rats, Sprague-Dawley, 1,2-Dimethylhydrazine, Carcinogens, Colonic Neoplasms prevention & control, Probiotics therapeutic use
- Abstract
Background: Probiotics are believed to have properties that lower the risk of colon cancer. However, the mechanisms by which they exert their beneficial effects are relatively unknown., Aim: To assess the impact of probiotics in preventing induction of colon carcinogenesis in rats., Methods: The rats were divided into six groups viz., normal control, Lactobacillus plantarum (AdF10)-treated, Lactobacillus rhamnosus GG (LGG)-treated, 1,2-dimethylhydrazine (DMH)-treated, L. plantarum (AdF10) + DMH-treated and L. rhamnosus GG (LGG) + DMH-treated. Both the probiotics were supplemented daily at a dose of 2 × 10
10 cells per day. DMH at a dose of 30 mg/kg body weight was administered subcutaneously twice a week for the first 4 weeks and then once every week for a duration of 16 weeks. Glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and catalase as protein expression of genes involved in apoptosis were assessed during DMH-induced colon carcinogenesis in rats., Results: DMH treatment decreased the activity of GSH, GPx, GST, SOD and catalase. However, AdF10 and LGG supplementation to DMH-treated rats significantly increased the activity of these enzymes. Further, DMH treatment revealed alterations in the protein expressions of various genes involved in the p53-mediated apoptotic pathway such as p53, p21, Bcl-2, Bax, caspase-9 and caspase-3, which, however, were shifted towards normal control levels upon simultaneous supplementation with probiotics., Conclusion: The present study suggests that probiotics can provide protection against oxidative stress and apoptotic-related protein disregulation during experimentally induced colon carcinogenesis.- Published
- 2018
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25. Molecular characterization and bioinformatics studies of a lipase from Bacillus thermoamylovorans BHK67.
- Author
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Sharma A, Meena KR, and Kanwar SS
- Subjects
- Amino Acid Sequence, Anions, Chromatography, Ion Exchange, Dynamic Light Scattering, Enzyme Stability, Extracellular Space enzymology, Hydrogen-Ion Concentration, Kinetics, Lipase chemistry, Lipase isolation & purification, Models, Molecular, Peptide Mapping, RNA, Ribosomal, 16S genetics, Sequence Analysis, RNA, Solvents, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Structural Homology, Protein, Substrate Specificity, Temperature, Bacillus enzymology, Computational Biology methods, Lipase genetics
- Abstract
A bacterium isolated from a hot-water spring identified as Bacillus thermoamylovorans BHK67 successfully produced a thermotolerant extracellular alkaliphilic lipase. The lipase was purified to homogeneity by anion exchange chromatography with 15-fold purification and 12.1% yield. The lipase appeared to be a hexameric protein as it possessed a single band of Mr 25kDa in SDS PAGE and 150kDa in Native PAGE. DLS analysis of purified Bacillus thermoamylovorans BHK67 lipase (BTL) also showed the molecular integrity, homogeneity and stability of the enzyme. The purified lipase showed maximum activity at pH 7.5 with a half-life of 10.5h at 55°C. Kinetic study of purified lipase by Lineweaver-Burk plot provided K
m (7.7mM),Vmax (90.9U/mL/min),Kcat (227.3s-1 ) and Kspec (29.4mMs-1 ) for substrate p-nitrophenylpalmitate.The purified lipase also showed astonishing stability following exposure to ethanol, n-propanol, iso-propanol, n-butanol and DMSO. Amino acid characterization of BTL by MALDI-TOF-MS showed considerable resemblance with lysophospholipase L1 related esterase of Lactobacillus ozensis DSM 23829. Experimental coupled molecular modeling postulated a structure-activity correlation of BTL as a probable contender in degradation of xenobiotic compounds, biocatalysis, biotransformation of compounds, synthesis of optically active compounds, foodstuff industry, anticancer therapeutics etc., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2018
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26. Adherence potential of indigenous lactic acid bacterial isolates obtained from fermented foods of Western Himalayas to intestinal epithelial Caco-2 and HT-29 cell lines.
- Author
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Sharma S and Kanwar SS
- Abstract
The adherence of bacteria to epithelial cells and mucosal surfaces is a prerequisite for their colonization in the gut and a key criterion for the selection of probiotics. In this study, the eleven indigenous lactic acid bacterial isolates obtained from traditional fermented foods of Western Himalayas were screened for their adherence potential to intestinal epithelial cell lines. The level of adherence of eleven indigenous isolates to Caco-2 and HT-29 cell lines varied from 2.45 ± 0.5 to 9.55 ± 0.76% and 4.11 ± 0.68 to 12.88 ± 0.63%, respectively. Percent adhesion of indigenous isolates to Caco-2 cells was relatively lower as compared to HT-29 cells. Indigenous isolate AdF10 ( L. plantarum ) was found to be the most adhesive to HT-29 and Caco-2 with corresponding figures of 12.88 ± 0.63 and 9.55 ± 0.76%, respectively. AdF4 ( B. coagulans ) was found to be least adhesive to HT-29 and Caco-2 with respective corresponding figures of 4.11 ± 0.68 and 2.45 ± 0.5%. Based on the percent adhesion values, indigenous isolate AdF10 ( L. plantarum ) was comparable to the reference probiotic strain L. rhamnosus GG-ATCC-53103 with respective adhesion of 13.5 ± 1.19 and 10.33 ± 0.64% to HT-29 and Caco-2 cell lines. It was closely followed by indigenous isolates AdF5 ( L. plantarum ) and AdF6 ( L. plantarum ); thus, indicating their potential as a promising probiotic candidates.
- Published
- 2017
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27. Elucidation of biocontrol mechanisms of Trichoderma harzianum against different plant fungal pathogens: Universal yet host specific response.
- Author
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Sharma V, Salwan R, Sharma PN, and Kanwar SS
- Subjects
- RNA, Messenger genetics, RNA, Messenger metabolism, Trichoderma genetics, Fusarium physiology, Host Specificity, Pest Control, Biological, Plants microbiology, Trichoderma physiology
- Abstract
In the present study, different transcripts of Trichoderma harzianum ThHP-3 were evaluated for their response against four fungal pathogens Fusarium oxysporum, Colletotrichum capsici, Colletotrichum truncatum and Gloesercospora sorghi using RT-qPCR. The time course study of T. harzianum transcripts related to signal transduction, lytic enzymes, secondary metabolites and various transporters revealed variation in expression against four fungal pathogens. In a broader term, the transcripts were upregulated at various time intervals but the optimum expression of cyp3, abc, nrp, tga1, pmk, ech42 and glh20 varied with respect to host fungi. Additionally, the expression of transcripts related to transporters/cytochromes was also observed against Fusarium oxysporum after 96h whereas transcripts related to secondary metabolites and lytic enzymes showed significant difference in expression against Colletotrichum spp. from 72 to 96h. This is first study on transcriptomic response of T. harzianum against pathogenic fungi which shows their host specific response., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2017
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28. A breakthrough in spontaneous coronary artery dissection pathogenesis: is it an inherited condition?
- Author
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Kanwar SS, Hayes SN, Olson TM, and Gulati R
- Published
- 2017
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29. Spontaneous splenic rupture in typhomalaria: A case report with review of literature.
- Author
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Malik S, Saran S, and Kanwar SS
- Abstract
Plasmodium vivax, which was previously considered 'benign', has come out with unusual severe symptoms. We, here present an unusual case of Plasmodium vivax malaria presenting with spontaneous splenic rupture with hemoperitoneum, renal and pulmonary dysfunction. Following conservative management, there was an uneventful recovery, and the patient was discharged in a good general condition.
- Published
- 2017
30. Ascorbyl palmitate synthesis in an organic solvent system using a Celite-immobilized commercial lipase (Lipolase 100L).
- Author
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Sharma S, Kanwar K, and Kanwar SS
- Abstract
Ascorbyl palmitate was synthesized using a Celite-immobilized commercial lipase (Lipolase 100L) in dimethylsulfoxide (DMSO) as an organic solvent system. Lipase immobilized by surface adsorption onto Celite 545 matrix and subsequently exposed to 1 % glutaraldehyde showed 75 % binding of protein. The Celite-bound lipase was optimally active at 75 °C and pH 8.5 under shaking and showed maximum hydrolytic activity toward p-NPP as a substrate. The bound lipase was found to be stimulated only in the presence of Al
3+ and EDTA. All surfactants (Tween-20, Tween-80 and Triton X-100) had an inhibitory effect on lipase activity. The optimization of various reaction conditions of ascorbyl palmitate was achieved considering one factor at a time. The esterification of ascorbic acid and palmitic acid was carried out with 1 M ascorbic acid and 2.5 M palmitic acid in DMSO at 75 °C for 18 h under shaking (120 rpm). Molecular sieves had an important effect on the ester synthesis resulting in an enhanced yield. The by-product (H2 O) produced in the reaction was scavenged by the molecular sieves (20 mg/ml) added in the reaction mixture which enhanced the ester yield to 80 %. The characterization of synthesized ester was done through FTIR spectroscopy.- Published
- 2016
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31. Lead Phytochemicals for Anticancer Drug Development.
- Author
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Singh S, Sharma B, Kanwar SS, and Kumar A
- Abstract
Cancer is a serious concern at present. A large number of patients die each year due to cancer illnesses in spite of several interventions available. Development of an effective and side effects lacking anticancer therapy is the trending research direction in healthcare pharmacy. Chemical entities present in plants proved to be very potential in this regard. Bioactive phytochemicals are preferential as they pretend differentially on cancer cells only, without altering normal cells. Carcinogenesis is a complex process and includes multiple signaling events. Phytochemicals are pleiotropic in their function and target these events in multiple manners; hence they are most suitable candidate for anticancer drug development. Efforts are in progress to develop lead candidates from phytochemicals those can block or retard the growth of cancer without any side effect. Several phytochemicals manifest anticancer function in vitro and in vivo . This article deals with these lead phytomolecules with their action mechanisms on nuclear and cellular factors involved in carcinogenesis. Additionally, druggability parameters and clinical development of anticancer phytomolecules have also been discussed.
- Published
- 2016
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32. Molecular cloning and characterization of ech46 endochitinase from Trichoderma harzianum.
- Author
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Sharma V, Salwan R, Sharma PN, and Kanwar SS
- Subjects
- Amino Acid Sequence, Base Sequence, Chitinases chemistry, Chitinases isolation & purification, Cloning, Molecular, Electrophoresis, Polyacrylamide Gel, Exons genetics, Fungal Proteins chemistry, Fungal Proteins isolation & purification, Hydrogen-Ion Concentration, Introns genetics, Ions, Metals pharmacology, Models, Molecular, Molecular Weight, Phylogeny, Protein Domains, Real-Time Polymerase Chain Reaction, Recombinant Proteins metabolism, Structural Homology, Protein, Temperature, Chitinases genetics, Fungal Proteins genetics, Trichoderma enzymology
- Abstract
In the present study, endochitinase of T. harzianum isolate-ThHP3 induced against mycelium of F. oxysporum was cloned, sequenced and characterized. The complete nucleotide sequence contained an ORF of 1293bp corresponding to 430 amino acids with 46kDa molecular weight and theoretical pI 5.59. The precursor protein contained 22 amino acids long signal peptide at N terminus. The domain architecture of endochitinase showed low complexity regions, presence of 1W9P domain specific to cyclopentapeptide and lack of carbohydrate binding modules. The ligand binding site of ech46 endochitinase was constituted by 10 amino acids. The cDNA encoding ech46 endochitinase was ligated into pET28a vector and transformed to E. coli BL21. The predicted molecular weight of recombinant endochitinase without signal peptide was 49.4kDa with a theoretical pI 6.67. SDS-PAGE analysis of purified 6xHis tagged protein showed a single band of 49kDa. The refolded enzyme was active under acidic conditions with a temperature and pH optima of 50°C and 4. Km and V
max for recombinant endochitinase using 4-pNP-(GlcNAc)3 were 315.2±0.36μM and 0.140±0.08μMmin-1 , respectively and the calculated kcat was 6.44min-1 . The RT-qPCR revealed induction of ech46 by phytopathogenic fungi., (Copyright © 2016 Elsevier B.V. All rights reserved.)- Published
- 2016
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33. Fermentation of Apple Juice with a Selected Yeast Strain Isolated from the Fermented Foods of Himalayan Regions and Its Organoleptic Properties.
- Author
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Kanwar SS and Keshani
- Abstract
Twenty-three Saccharomyces cerevisiae strains isolated from different fermented foods of Western Himalayas have been studied for strain level and functional diversity in our department. Among these 23 strains, 10 S. cerevisiae strains on the basis of variation in their brewing traits were selected to study their organoleptic effect at gene level by targeting ATF1 gene, which is responsible for ester synthesis during fermentation. Significant variation was observed in ATF1 gene sequences, suggesting differences in aroma and flavor of their brewing products. Apple is a predominant fruit in Himachal Pradesh and apple cider is one of the most popular drinks all around the world hence, it was chosen for sensory evaluation of six selected yeast strains. Organoleptic studies and sensory analysis suggested Sc21 and Sc01 as best indigenous strains for soft and hard cider, respectively, indicating their potential in enriching the local products with enhanced quality.
- Published
- 2016
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34. Acute coronary syndromes without coronary plaque rupture.
- Author
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Kanwar SS, Stone GW, Singh M, Virmani R, Olin J, Akasaka T, and Narula J
- Subjects
- Acute Coronary Syndrome pathology, Acute Coronary Syndrome therapy, Aged, Biopsy, Coronary Angiography, Coronary Artery Disease pathology, Coronary Artery Disease therapy, Coronary Vessels diagnostic imaging, Diagnostic Imaging methods, Fibrosis, Humans, Male, Predictive Value of Tests, Prognosis, Risk Factors, Rupture, Spontaneous, Tomography, Optical Coherence, Ultrasonography, Interventional, Acute Coronary Syndrome etiology, Coronary Artery Disease complications, Coronary Vessels pathology, Plaque, Atherosclerotic
- Abstract
The latest advances in plaque imaging have provided clinicians with opportunities to treat acute coronary syndrome (ACS) and provide individualized treatment recommendations based not only on clinical manifestations, angiographic characteristics, and biomarker data, but also on the findings of plaque morphology. Although a substantial proportion of ACS events originate from plaques with an intact fibrous cap (IFC), clinicians predominantly equate ACS with plaque rupture arising from thin-cap fibroatheromas. In this Review, we discuss the recent advances in our understanding of plaque morphology in ACS with IFC, reviewing contemporary data from intravascular imaging. We also explore whether use of such imaging might provide a roadmap for more effective management of patients with ACS.
- Published
- 2016
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35. Lipase catalysis in organic solvents: advantages and applications.
- Author
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Kumar A, Dhar K, Kanwar SS, and Arora PK
- Abstract
Lipases are industrial biocatalysts, which are involved in several novel reactions, occurring in aqueous medium as well as non-aqueous medium. Furthermore, they are well-known for their remarkable ability to carry out a wide variety of chemo-, regio- and enantio-selective transformations. Lipases have been gained attention worldwide by organic chemists due to their general ease of handling, broad substrate tolerance, high stability towards temperatures and solvents and convenient commercial availability. Most of the synthetic reactions on industrial scale are carried out in organic solvents because of the easy solubility of non-polar compounds. The effect of organic system on their stability and activity may determine the biocatalysis pace. Because of worldwide use of lipases, there is a need to understand the mechanisms behind the lipase-catalyzed reactions in organic solvents. The unique interfacial activation of lipases has always fascinated enzymologists and recently, biophysicists and crystallographers have made progress in understanding the structure-function relationships of these enzymes. The present review describes the advantages of lipase-catalyzed reactions in organic solvents and various effects of organic solvents on their activity.
- Published
- 2016
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36. Purification and Characterization of an Extracellular Cholesterol Oxidase of Bacillus subtilis Isolated from Tiger Excreta.
- Author
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Kumari L and Kanwar SS
- Subjects
- Animals, Buffers, Cell Line, Cell-Free System, Chromatography, Affinity, Detergents, Electrophoresis, Polyacrylamide Gel, Enzyme Stability, Humans, Hydrogen-Ion Concentration, Kinetics, Phylogeny, Tigers, Bacillus subtilis enzymology, Cholesterol Oxidase metabolism, Feces microbiology
- Abstract
A mesophilic Bacillus sp. initially isolated from tiger excreta and later identified as a Bacillus subtilis strain was used to produce an extracellular cholesterol oxidase (COX) in cholesterol-enriched broth. This bacterial isolate was studied for the production of COX by manipulation of various physicochemical parameters. The extracellular COX was successfully purified from the cell-free culture broth of B. subtilis by successive salting out with ammonium sulfate, dialysis, and riboflavin-affinity chromatography. The purified COX was characterized for its molecular mass/structure and stability. The enzyme possessed some interesting properties such as high native Mr (105 kDa), multimeric (pentamer of ∼21 kDa protein) nature, organic solvent compatibility, and a half-life of ∼2 h at 37 °C. The bacterial COX exhibited ∼22 % higher activity in potassium phosphate buffer (pH 7.5) in the presence of a nonionic detergent Triton X-100 at 0.05 % (v/v). The K m and V max value of COX of B. subtilis COX were found to be 3.25 mM and 2.17 μmol min ml(-1), respectively. The purified COX showed very little cytotoxicity associated with it.
- Published
- 2016
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37. Gallic acid-based alkyl esters synthesis in a water-free system by celite-bound lipase of Bacillus licheniformis SCD11501.
- Author
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Sharma S, Kanwar SS, Dogra P, and Chauhan GS
- Subjects
- Enzymes, Immobilized metabolism, Esterification, Esters, Ethanol metabolism, Gallic Acid analogs & derivatives, Magnetic Resonance Spectroscopy, Methanol metabolism, Propyl Gallate metabolism, Spectroscopy, Fourier Transform Infrared, Temperature, Water, Bacillus enzymology, Diatomaceous Earth chemistry, Gallic Acid metabolism, Lipase metabolism
- Abstract
Gallic acid (3, 4, 5- trihydroxybenzoic acid) is an important antioxidant, anti-inflammatory, and radical scavenging agent. In the present study, a purified thermo-tolerant extra-cellular lipase of Bacillus licheniformis SCD11501 was successfully immobilized by adsorption on Celite 545 gel matrix followed by treatment with a cross-linking agent, glutaraldehyde. The celite-bound lipase treated with glutaraldehyde showed 94.8% binding/retention of enzyme activity (36 U/g; specific activity 16.8 U/g matrix; relative increase in enzyme activity 64.7%) while untreated matrix resulted in 88.1% binding/retention (28.0 U/g matrix; specific activity 8.5 U/g matrix) of lipase. The celite-bound lipase was successfully used to synthesis methyl gallate (58.2%), ethyl gallate (66.9%), n-propyl gallate (72.1%), and n-butyl gallate (63.8%) at 55(o) C in 10 h under shaking (150 g) in a water-free system by sequentially optimizing various reaction parameters. The low conversion of more polar alcohols such as methanol and ethanol into their respective gallate esters might be due to the ability of these alcohols to severely remove water from the protein hydration shell, leading to enzyme inactivation. Molecular sieves added to the reaction mixture resulted in enhanced yield of the alkyl ester(s). The characterization of synthesised esters was done through fourier transform infrared (FTIR) spectroscopy and (1) H NMR spectrum analysis., (© 2015 American Institute of Chemical Engineers.)
- Published
- 2015
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38. Lipopeptides as the antifungal and antibacterial agents: applications in food safety and therapeutics.
- Author
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Meena KR and Kanwar SS
- Subjects
- Animals, Humans, Lipopeptides chemistry, Surface-Active Agents pharmacology, Anti-Bacterial Agents pharmacology, Antifungal Agents pharmacology, Food Safety, Lipopeptides pharmacology
- Abstract
A lot of crops are destroyed by the phytopathogens such as fungi, bacteria, and yeast leading to economic losses to the farmers. Members of the Bacillus genus are considered as the factories for the production of biologically active molecules that are potential inhibitors of growth of phytopathogens. Plant diseases constitute an emerging threat to global food security. Many of the currently available antimicrobial agents for agriculture are highly toxic and nonbiodegradable and thus cause extended environmental pollution. Moreover, an increasing number of phytopathogens have developed resistance to antimicrobial agents. The lipopeptides have been tried as potent versatile weapons to deal with a variety of phytopathogens. All the three families of Bacillus lipopeptides, namely, Surfactins, Iturins and Fengycins, have been explored for their antagonistic activities towards a wide range of phytopathogens including bacteria, fungi, and oomycetes. Iturin and Fengycin have antifungal activities, while Surfactin has broad range of potent antibacterial activities and this has also been used as larvicidal agent. Interestingly, lipopeptides being the molecules of biological origin are environmentally acceptable.
- Published
- 2015
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39. Cyclooxygenase as a target in chemoprevention by probiotics during 1,2-dimethylhydrazine induced colon carcinogenesis in rats.
- Author
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Walia S, Kamal R, Kanwar SS, and Dhawan DK
- Subjects
- 1,2-Dimethylhydrazine adverse effects, Animals, Body Weight, Colonic Neoplasms chemically induced, Cyclooxygenase 1 genetics, Cyclooxygenase 2 genetics, Down-Regulation, Female, Lactobacillus plantarum metabolism, Lacticaseibacillus rhamnosus metabolism, Membrane Proteins genetics, N-Acetylneuraminic Acid blood, Rats, Rats, Sprague-Dawley, Chemoprevention, Colonic Neoplasms therapy, Cyclooxygenase 1 metabolism, Cyclooxygenase 2 metabolism, Membrane Proteins metabolism, Probiotics administration & dosage
- Abstract
The present study was undertaken to assess the effects of potential probiotics in regulating the activity of cyclooxygenase-2 (COX-2) along with other morphological and histological analysis during 1,2-dimethylhydrazine (DMH) induced colon carcinogenesis in rats. The rats were divided into 6 groups viz., normal control, Lactobacillus plantarum (AdF10) treated, Lactobacillus rhamnosus GG (LGG) treated, DMH treated, AdF10 + DMH treated and LGG + DMH treated. Probiotics were supplemented to rats at dose levels of 2 × 10(10) cells per day for 6 days in a week. All the treatments were continued for a period of 16 wk. DMH treatment resulted in a statistically significant increase in the levels of total sialic acid (TSA). However, on supplementation with probiotics, a significant reduction in TSA was observed. DMH treatment brought about a significant increase in the expression of COX-2. But, supplementation of probiotics brought down the protein expression to moderate level. Further, supplementation with probiotics was also able to reduce tumor incidence, tumor multiplicity and average tumor size. Therefore, treatment with probiotics has the potential of providing protection against colon cancer by suppressing the COX-2 expression as one of the protective mechanisms.
- Published
- 2015
- Full Text
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40. Microfluidic device (ExoChip) for on-chip isolation, quantification and characterization of circulating exosomes.
- Author
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Kanwar SS, Dunlay CJ, Simeone DM, and Nagrath S
- Subjects
- Humans, Male, MicroRNAs blood, MicroRNAs isolation & purification, RNA, Neoplasm blood, RNA, Neoplasm isolation & purification, Cell-Derived Microparticles chemistry, Cell-Derived Microparticles metabolism, Cell-Derived Microparticles ultrastructure, Exosomes chemistry, Exosomes metabolism, Exosomes ultrastructure, Lab-On-A-Chip Devices, Microfluidic Analytical Techniques instrumentation, Microfluidic Analytical Techniques methods, Pancreatic Neoplasms blood
- Abstract
Membrane bound vesicles, including microvesicles and exosomes, are secreted by both normal and cancerous cells into the extracellular space and in blood circulation. These circulating extracellular vesicles (cirEVs) and exosomes in particular are recognized as a potential source of disease biomarkers. However, to exploit the use of circulatory exosomes as a biomarker, a rapid, high-throughput and reproducible method is required for their isolation and molecular analysis. We have developed a simple, low cost microfluidic-based platform to isolate cirEVs enriched in exosomes directly from blood serum allowing simultaneous capture and quantification of exosomes in a single device. To capture specific exosomes, we employed "ExoChip", a microfluidic device fabricated in polydimethylsiloxane (PDMS) and functionalized with antibodies against CD63, an antigen commonly overexpressed in exosomes. Subsequent staining with a fluorescent carbocyanine dye (DiO) that specifically labels the exosomes, we quantitated exosomes using a standard plate-reader. Ten independent ExoChip experiments performed using serum obtained from five pancreatic cancer patients and five healthy individuals revealed a statistically significant increase (2.34 ± 0.31 fold, p < 0.001) in exosomes captured in cancer patients when compared to healthy individuals. Exosomal origins of ExoChip immobilized vesicles were further confirmed using immuno-electron-microscopy and Western blotting. In addition, we demonstrate the ability of ExoChip to recover exosomes with intact RNA enabling profiling of exosomal-microRNAs through openarray analysis, which has potential applications in biomarker discovery. Based on our findings, ExoChip is a well suited platform to be used as an exosome-based diagnostic and research tool for molecular screening of human cancers.
- Published
- 2014
- Full Text
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41. Organic solvent tolerant lipases and applications.
- Author
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Sharma S and Kanwar SS
- Subjects
- Catalysis, Enzymes, Immobilized chemistry, Solubility, Substrate Specificity, Lipase chemistry, Organic Chemicals chemistry, Solvents chemistry
- Abstract
Lipases are a group of enzymes naturally endowed with the property of performing reactions in aqueous as well as organic solvents. The esterification reactions using lipase(s) could be performed in water-restricted organic media as organic solvent(s) not only improve(s) the solubility of substrate and reactant in reaction mixture but also permit(s) the reaction in the reverse direction, and often it is easy to recover the product in organic phase in two-phase equilibrium systems. The use of organic solvent tolerant lipase in organic media has exhibited many advantages: increased activity and stability, regiospecificity and stereoselectivity, higher solubility of substrate, ease of products recovery, and ability to shift the reaction equilibrium toward synthetic direction. Therefore the search for organic solvent tolerant enzymes has been an extensive area of research. A variety of fatty acid esters are now being produced commercially using immobilized lipase in nonaqueous solvents. This review describes the organic tolerance and industrial application of lipases. The main emphasis is to study the nature of organic solvent tolerant lipases. Also, the potential industrial applications that make lipases the biocatalysts of choice for the present and future have been presented.
- Published
- 2014
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42. Influence of phenolic compounds of Kangra tea [Camellia sinensis (L) O Kuntze] on bacterial pathogens and indigenous bacterial probiotics of Western Himalayas.
- Author
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Sourabh A, Kanwar SS, Sud RG, Ghabru A, and Sharma OP
- Subjects
- Anti-Bacterial Agents chemistry, Anti-Bacterial Agents isolation & purification, Bacteria growth & development, Chromatography, High Pressure Liquid, Intercellular Signaling Peptides and Proteins chemistry, Intercellular Signaling Peptides and Proteins isolation & purification, Microbial Viability drug effects, Phenols chemistry, Phenols isolation & purification, Plant Extracts chemistry, Plant Extracts isolation & purification, Anti-Bacterial Agents pharmacology, Bacteria drug effects, Camellia sinensis chemistry, Intercellular Signaling Peptides and Proteins pharmacology, Phenols pharmacology, Plant Extracts pharmacology, Probiotics
- Abstract
Phenolic compounds of nutraceutical importance viz., catechins (C), (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin-3-gallate (ECG) were estimated in fresh green tea shoots of Camellia sinensis (L) O Kuntze cultivar. The total polyphenols and total catechins were in the range of 219.90 to 317.81 and 140.83 to 271.39 g/kg, respectively in monthly samples of tea. The values of C, EC, EGC, EGCG and ECG in tea powders as analyzed through high performance liquid chromatography (HPLC) were in the range of 1.560 to 3.661, 13.338 to 27.766, 26.515 to 39.597, 62.903 to 102.168 and 18.969 to 39.469 mg/g, respectively. Effect of tea extracts and standard flavanols against five pathogenic bacteria viz., Listeria monocytogenes (MTCC-839), Pseudomonas aeruginosa (MTCC-741), Bacillus cereus (MTCC-1272), Staphylococcus aureus (MTCC-96) and Escherichia coli (MTCC-443), and eleven indigenous potential bacterial probiotics belonging to genera Enterococcus, Bacillus and Lactobacillus spp. obtained from fermented foods of Western Himalayas, was investigated. EGCG, ECG and EGC exhibited antibacterial activity but, C and EC did not show this activity. Tea extracts having high concentrations of EGCG and ECG were more potent in antibacterial action against bacterial pathogens. Tea extracts and standard flavan-3-ols augmented viability of potential probiotics in an order of EGCG > EGC > ECG > EC > C. Tea extracts and standard flavanols had no antibacterial activity against Escherichia coli (MTCC-443) but, in combination with probiotic culture supernatants, this activity was seen. The Kangra tea thus, exerts antibacterial effect on bacterial pathogens through EGCG, ECG and EGC constituents while stimulatory effect on growth of indigenous potential probiotics.
- Published
- 2014
- Full Text
- View/download PDF
43. L-methionase: a therapeutic enzyme to treat malignancies.
- Author
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Sharma B, Singh S, and Kanwar SS
- Subjects
- Animals, Humans, Models, Biological, Carbon-Sulfur Lyases therapeutic use, Methionine metabolism, Molecular Targeted Therapy methods, Neoplasm Proteins metabolism, Neoplasms drug therapy, Neoplasms metabolism
- Abstract
Cancer is an increasing cause of mortality and morbidity throughout the world. L-methionase has potential application against many types of cancers. L-Methionase is an intracellular enzyme in bacterial species, an extracellular enzyme in fungi, and absent in mammals. L-Methionase producing bacterial strain(s) can be isolated by 5,5'-dithio-bis-(2-nitrobenzoic acid) as a screening dye. L-Methionine plays an important role in tumour cells. These cells become methionine dependent and eventually follow apoptosis due to methionine limitation in cancer cells. L-Methionine also plays an indispensable role in gene activation and inactivation due to hypermethylation and/or hypomethylation. Membrane transporters such as GLUT1 and ion channels like Na(2+), Ca(2+), K(+), and Cl(-) become overexpressed. Further, the α-subunit of ATP synthase plays a role in cancer cells growth and development by providing them enhanced nutritional requirements. Currently, selenomethionine is also used as a prodrug in cancer therapy along with enzyme methionase that converts prodrug into active toxic chemical(s) that causes death of cancerous cells/tissue. More recently, fusion protein (FP) consisting of L-methionase linked to annexin-V has been used in cancer therapy. The fusion proteins have advantage that they have specificity only for cancer cells and do not harm the normal cells.
- Published
- 2014
- Full Text
- View/download PDF
44. Peroxidase(s) in environment protection.
- Author
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Bansal N and Kanwar SS
- Subjects
- Enzyme Activation, Enzyme Stability, Conservation of Natural Resources methods, Peroxidases chemistry, Water chemistry, Water Pollutants, Chemical chemistry, Water Pollutants, Chemical isolation & purification, Water Purification methods
- Abstract
Industrial discharges of untreated effluents into water bodies and emissions into air have deteriorated the quality of water and air, respectively. The huge amount of pollutants derived from industrial activities represents a threat for the environment and ecologic equilibrium. Phenols and halogenated phenols, polycyclic aromatic hydrocarbons (PAH), endocrine disruptive chemicals (EDC), pesticides, dioxins, polychlorinated biphenyls (PCB), industrial dyes, and other xenobiotics are among the most important pollutants. Peroxidases are enzymes that are able to transform a variety of compounds following a free radical mechanism, thereby yielding oxidized or polymerized products. The peroxidase transformation of these pollutants is accompanied by a reduction in their toxicity, due to loss of biological activity, reduction in the bioavailability, or the removal from aqueous phase, especially when the pollutant is found in water. The review describes the sources of peroxidases, the reactions catalyzed by them, and their applications in the management of pollutants in the environment.
- Published
- 2013
- Full Text
- View/download PDF
45. Effect of cationic ionophore monensin on the lipid composition and fluidity of rat epididymal spermatozoal membrane.
- Author
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Sharma P, Kanwar SS, and Sanyal SN
- Subjects
- Animals, Calcium metabolism, Cholesterol analysis, Gangliosides analysis, Male, Rats, Rats, Wistar, Epididymis drug effects, Membrane Fluidity drug effects, Membrane Lipids analysis, Monensin pharmacology, Sodium Ionophores pharmacology, Spermatozoa drug effects
- Abstract
The present study was aimed at exploring the effect of monensin, an antibiotic carboxylic polyether ionophore specific for Na(+), on the structural, chemical, and physiological changes of the epididymal sperm of Wistar rats. Animals received monensin at the dose of 3.5 mg/kg body weight daily orally for 70 days, a treatment duration that corresponds to the spermatogenic cycle in rats. At the end of the treatment regime, three regions of the epididymis were separated and the spermatozoa were collected. The plasma membranes of the spermatozoa were isolated and lipid composition, such total lipid, phospholipid, cholesterol, and ganglioside-sialic acid, was studied. Membrane dynamic behavior was investigated by lipid translational fluidity by pyrene excimer formation and rotational diffusion by diphenyl hexatriene polarization and anisotropy parameter. Structural changes in membrane were also evaluated by the dye-binding study with anilino naphthalene sulphonic acid. The results showed marked changes in lipid compositions, fluidity parameters, and kinetics of fluorescent dye binding in the epididymis, and it can be concluded that monensin, by interfering with normal physiological changes in spermatozoal maturation, may provide the basis of certain molecular intervention in the fertilizing capability of the epididymal spermatozoa and thereby may induce antifertility properties in male rats.
- Published
- 2013
- Full Text
- View/download PDF
46. Bioresolution of benzyl glycidyl ether using whole cells of Bacillus alcalophilus.
- Author
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Bala N, Kaur K, Chimni SS, Saini HS, and Kanwar SS
- Subjects
- Carbon metabolism, Culture Media chemistry, Hydrogen-Ion Concentration, Nitrogen metabolism, Peptones metabolism, Sucrose metabolism, Temperature, Bacillus metabolism, Biotechnology methods, Epoxy Compounds metabolism
- Abstract
The incubation of whole Bacillus alcalophilus cells grown on a mineral supplemented medium (MSM) containing 1% (w/v) sucrose as carbon source, 1.2% (w/v) tryptone as nitrogen source at pH 6.5 and temperature 30 °C in 24 h kinetically resolved benzyl glycidyl ether (1 mg/ml) to provide (S)-benzyl glycidyl ether with 30% ee and (R)-3-benzyloxypropane-1,2-diol with 40% ee., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2012
- Full Text
- View/download PDF
47. EGFR regulation of colon cancer stem-like cells during aging and in response to the colonic carcinogen dimethylhydrazine.
- Author
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Nautiyal J, Du J, Yu Y, Kanwar SS, Levi E, and Majumdar AP
- Subjects
- Aging pathology, Animals, Antibodies, Monoclonal pharmacology, Antibodies, Monoclonal, Humanized, Antineoplastic Agents pharmacology, Biomarkers, Tumor metabolism, Cetuximab, Colon cytology, Colon metabolism, Colonic Neoplasms metabolism, Colonic Neoplasms pathology, ErbB Receptors genetics, Gene Expression Regulation, Neoplastic drug effects, Gene Expression Regulation, Neoplastic physiology, Intestinal Mucosa cytology, Male, MicroRNAs genetics, MicroRNAs metabolism, Rats, Aging physiology, Carcinogens toxicity, Dimethylhydrazines toxicity, ErbB Receptors metabolism, Neoplastic Stem Cells drug effects, Neoplastic Stem Cells metabolism
- Abstract
One of the most consistent pathological conditions in the gastrointestinal tract with advancing age is malignancy, particularly gastrointestinal cancers, the incidence of which increases sharply with aging. Although the reasons for the age-related rise in colorectal cancer are not fully understood, we hypothesize that aging increases susceptibility of the colon to carcinogen(s)/toxicant(s), leading to an increase in cancer stem-like cells (CSLCs) that express cancer stem cell markers, in the colonic mucosa. The current study demonstrates that aging is associated with increased expression of several colon CSLC markers [CD44, CD166, and aldehyde dehydrogenase 1 (ALDH-1)] and a higher proportion of cells expressing these markers. Aging is also accompanied by increased expression of miR-21 in colon. These increases are further increased in response to the colonic carcinogen dimethylhydrazine (DMH). Aging is also associated with increased tyrosine-phosphorylated epidermal growth factor receptor (EGFR). Inhibition of EGFR using the EGFR inhibitor cetuximab abrogated the age-related increase in CD166 and ALDH-1 as well as miRNA (miR)-21. Our results provide new evidence that aging and DMH are associated with increases in CSLC biomarkers and miR21, each of which have been linked to colorectal cancer. EGFR inhibition attenuates these changes, indicating a role for EGFR in age- and mutagen-associated changes in CSLCs.
- Published
- 2012
- Full Text
- View/download PDF
48. Regulation of colon cancer recurrence and development of therapeutic strategies.
- Author
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Kanwar SS, Poolla A, and Majumdar AP
- Abstract
Recurrence of colon cancer still remains a major issue which affects nearly 50% of patients treated by conventional therapeutics. Although the underlying causative factor(s) is not fully understood, development of drug-resistance has been associated with induction of cancer stem or stem-like cells (CSCs) which constitute a small sub-population of tumor cells known to be highly resistant to chemotherapy. In fact, the discovery of CSCs in a variety of tumors (including colon cancer) has changed the view of carcinogenesis and therapeutic strategies. Emerging reports have indicated that to improve patient outcomes, conventional anticancer therapies should be replaced with specific approaches targeting CSCs. Thus, therapeutic strategies that specifically target CSCs are being sought to reduce the risk of relapse and metastasis. In order to specifically target colon CSCs (while sparing somatic intestinal stem cells), it is critical to identify unique deregulated pathways responsible for self-renewal of CSCs and colon cancer recurrence. Colon CSCs present a unique opportunity to better understand the biology of solid tumors. Thus, a better understanding of the clinical signs and symptoms of colon cancer patients (undergoing surgery or chemotherapy) during perioperative periods, along with the underlying regulatory events affecting the stem/progenitor cell self-renewal and differentiation of colon epithelial cells, is of immense importance. In this review we discuss the implication of clinical factors and the emerging role of CSCs during recurrence of colon cancer along with the development of new therapeutic strategies involving the use of natural agents.
- Published
- 2012
- Full Text
- View/download PDF
49. In vitro antibacterial and antimalarial activity of dehydrophenylalanine-containing undecapeptides alone and in combination with drugs.
- Author
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Sharma SP, Sharma J, Kanwar SS, and Chauhan VS
- Subjects
- Antimicrobial Cationic Peptides chemistry, Circular Dichroism, Drug Interactions, Humans, Microbial Sensitivity Tests, Phenylalanine analysis, Protein Conformation, Structure-Activity Relationship, Anti-Bacterial Agents pharmacology, Antimalarials pharmacology, Antimicrobial Cationic Peptides pharmacology, Escherichia coli drug effects, Phenylalanine analogs & derivatives, Plasmodium falciparum drug effects, Staphylococcus aureus drug effects
- Abstract
A set of three cationic undecapeptides, analogous to the previously reported peptide VS2 (KWΔFWKΔFVKΔFVK), was created by alanine substitution in order to probe the effect of hydrophobicity on peptide activity. The activities of these peptides were determined against Escherichia coli, Staphylococcus aureus and the malaria parasite Plasmodium falciparum. VA1, the closest analogue of VS2, showed five-fold augmented activity [minimum inhibitory concentration (MIC)=10 μM] against the Gram-positive bacterium S. aureus. The designed analogues were non-haemolytic and non-cytotoxic at their MICs and clinically relevant concentrations. By alanine substitution, it was also possible to probe the critical role of tryptophan residues in determining peptide potency. Circular dichroism studies of the peptides in a membrane-mimetic system showed a correlation between peptide helicity and antimicrobial activity. The peptides were also tested in combination with sublethal concentrations of antibiotic drugs (rifampicin and kanamycin) and the antimalarial drug chloroquine. In combination with these drugs, the effect of the peptides was synergistic or additive. These results provide insight into basic design principles for generating new clinically relevant lead peptides. It also provides an alternative strategy where a peptide and a non-peptide drug can be used in combination to battle increasingly drug-resistant microbes., (Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
50. The single functional blast resistance gene Pi54 activates a complex defence mechanism in rice.
- Author
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Gupta SK, Rai AK, Kanwar SS, Chand D, Singh NK, and Sharma TR
- Subjects
- Down-Regulation genetics, Enzymes genetics, Enzymes metabolism, Gene Expression Profiling, Gene Expression Regulation, Plant genetics, Host-Pathogen Interactions, Oligonucleotide Array Sequence Analysis, Oryza enzymology, Oryza microbiology, Plant Diseases microbiology, Plant Leaves enzymology, Plant Leaves genetics, Plant Leaves immunology, Plant Leaves microbiology, Plant Proteins metabolism, Plants, Genetically Modified, RNA, Plant genetics, Stress, Physiological, Transcription Factors genetics, Transcription Factors metabolism, Transcriptome, Up-Regulation genetics, Disease Resistance genetics, Magnaporthe physiology, Oryza genetics, Oryza immunology, Plant Diseases immunology, Plant Proteins genetics
- Abstract
The Pi54 gene (Pi-k(h)) confers a high degree of resistance to diverse strains of the fungus Magnaporthe oryzae. In order to understand the genome-wide co-expression of genes in the transgenic rice plant Taipei 309 (TP) containing the Pi54 gene, microarray analysis was performed at 72 h post-inoculation of the M. oryzae strain PLP-1. A total of 1154 differentially expressing genes were identified in TP-Pi54 plants. Of these, 587 were up-regulated, whereas 567 genes were found to be down-regulated. 107 genes were found that were exclusively up-regulated and 58 genes that were down- regulated in the case of TP-Pi54. Various defence response genes, such as callose, laccase, PAL, and peroxidase, and genes related to transcription factors like NAC6, Dof zinc finger, MAD box, bZIP, and WRKY were found to be up-regulated in the transgenic line. The enzymatic activities of six plant defence response enzymes, such as peroxidase, polyphenol oxidase, phenylalanine ammonia lyase, β-glucosidase, β-1,3-glucanase, and chitinase, were found to be significantly high in TP-Pi54 at different stages of inoculation by M. oryzae. The total phenol content also increased significantly in resistant transgenic plants after pathogen inoculation. This study suggests the activation of defence response and transcription factor-related genes and a higher expression of key enzymes involved in the defence response pathway in the rice line TP-Pi54, thus leading to incompatible host-pathogen interaction.
- Published
- 2012
- Full Text
- View/download PDF
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