226
|
Verma YK, Gangenahalli GU, Singh VK, Gupta P, Chandra R, Sharma RK, Raj HG. Cell death regulation by B-cell lymphoma protein. Apoptosis 2006; 11:459-71. [PMID: 16547596 DOI: 10.1007/s10495-006-5702-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Bcl-2 (B Cell Lymphoma) protein is an anti-apoptotic member of Bcl-2 family, which is comprised of pro- and anti-apoptotic members. It regulates cellular proliferation and death by inter- and intra-family interactions. It has a potential to suppress apoptotic cell death under variety of stress conditions by modulating mitochondrial transmembrane potential. However, prevalence of constitutively activated Bcl-2 cellular activity is not always required in cells; a mechanism likely exists in cells, which controls its activity. When expression of Bcl-2 is unregulated, it generates lymphoma like, follicular B-cell lymphoma. This article reviews the structural and functional regulation of Bcl-2 activity at transcriptional, translational, domain, structural and post-translational level, which also accounts for the effects of its deletion and site-directed mutants in the regulation of cellular proliferation and differentiation in vitro and in vivo. This concisely reviewed information on Bcl-2 helps us to update our understanding of cell death and its modulation by Bcl-2 and its mutant's interaction, which has gained therapeutic benefits in cell growth and proliferation, particularly for sensitive human hematopoietic stem cells.
Collapse
|
227
|
Nigam A, Singh VK, Prakash A. Vaginal vs. oral misoprostol for mid-trimester abortion. Int J Gynaecol Obstet 2006; 92:270-1. [PMID: 16430901 DOI: 10.1016/j.ijgo.2005.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2005] [Revised: 11/22/2005] [Accepted: 11/23/2005] [Indexed: 11/26/2022]
|
228
|
Wheen LC, Anderson NE, Baker PCH, Singh VK, Synek BJL. Leptomeningeal infiltration as the presenting manifestation of a malignant glioma. J Clin Neurosci 2006; 13:298-301. [PMID: 16431108 DOI: 10.1016/j.jocn.2005.01.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2004] [Accepted: 01/11/2005] [Indexed: 11/23/2022]
Abstract
Infiltration of the leptomeninges by a malignant glioma typically occurs with recurrent supratentorial tumors, but patients may present with leptomeningeal gliomatosis before the primary tumor is diagnosed. This report describes two patients who presented with headache and signs of multifocal neurological disease. One of the patients had neurofibromatosis type I. In both patients the cerebrospinal fluid examination showed a mild pleocytosis, but malignant cells were not detected. The diagnosis of leptomeningeal gliomatosis was not confirmed until autopsy, but in retrospect imaging showed a small, asymptomatic primary tumor in both patients. Leptomeningeal gliomatosis should be considered in the differential diagnosis of chronic meningitis, if the patient is afebrile and if there are multifocal neurological signs, even when a primary tumor is not obvious.
Collapse
|
229
|
Vats DP, Parihar JKS, Singh VK, Trehan HS, Khan MA. AC/PC Intraocular Lens Exchange with Penetrating Keratoplasty in Pseudophakic Bullous Keratopathy. Med J Armed Forces India 2006; 62:11-3. [DOI: 10.1016/s0377-1237(06)80143-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2001] [Accepted: 06/28/2005] [Indexed: 10/18/2022] Open
|
230
|
Yadav VS, Mishra KP, Singh DP, Mehrotra S, Singh VK. Immunomodulatory effects of curcumin. Immunopharmacol Immunotoxicol 2005; 27:485-97. [PMID: 16237958 DOI: 10.1080/08923970500242244] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Curcumin (diferuloylmethane), found in the spice turmeric, exhibits anti-inflammatory, antioxidant, and chemopreventive activities. However, the effect of curcumin on the immunological responses largely remains unknown. In this study we have investigated the effect of curcumin on mitogen (phytohaemagglutinin; PHA) stimulated T-cell proliferation, natural killer (NK) cell cytotoxicity, production of cytokines by human peripheral blood mononuclear cells (PBMCs), nitric oxide (NO) production in mouse macrophage cells, RAW-264.7. Furthermore, we have carried out an electromobility shift assay to elucidate the mechanism of action of curcumin at DNA protein interaction level. We observed that curcumin inhibits PHA-induced T-cell proliferation, interleukin-2 production, NO generation, and lipopolysachharide-induced nuclear factor-kappaB (NF-kappaB) and augments NK cell cytotoxicity. Our results suggest that curcumin most likely inhibits cell proliferation and cytokine production by inhibiting NF-kappaB target genes involved in the induction of these immune parameters.
Collapse
|
231
|
Zheng J, Singh VK, Jia Z. Identification of an ITPase/XTPase in Escherichia coli by structural and biochemical analysis. Structure 2005; 13:1511-20. [PMID: 16216582 DOI: 10.1016/j.str.2005.07.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2005] [Revised: 07/14/2005] [Accepted: 07/17/2005] [Indexed: 01/13/2023]
Abstract
Inosine triphosphate (ITP) and xanthosine triphosphate (XTP) are formed upon deamination of ATP and GTP as a result of exposure to chemical mutagens and oxidative damage. Nucleic acid synthesis requires safeguard mechanisms to minimize undesired lethal incorporation of ITP and XTP. Here, we present the crystal structure of YjjX, a protein of hitherto unknown function. The three-dimensional fold of YjjX is similar to those of Mj0226 from Methanococcus janschii, which possesses nucleotidase activity, and of Maf from Bacillus subtilis, which can bind nucleotides. Biochemical analyses of YjjX revealed it to exhibit specific phosphatase activity for inosine and xanthosine triphosphates and have a possible interaction with elongation factor Tu. The enzymatic activity of YjjX as an inosine/xanthosine triphosphatase provides evidence for a plausible protection mechanism by clearing the noncanonical nucleotides from the cell during oxidative stress in E. coli.
Collapse
|
232
|
Nigam A, Singh VK, Dubay P, Pandey K, Bhagoliwal A, Prakash A. Misoprostol vs. oxytocin for induction of labor at term. Int J Gynaecol Obstet 2005; 86:398-400. [PMID: 15325864 DOI: 10.1016/j.ijgo.2004.05.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2004] [Revised: 05/12/2004] [Accepted: 05/13/2004] [Indexed: 11/23/2022]
Abstract
Efficacy of misoprostol was studied for induction of labor at term. Seventy patients were randomized to Group A (n = 36, oral misoprostol 50 microg four hourly to maximum of 5 doses) and B (n = 34, continuous oxytocin infusion). Induction-delivery interval was shorter with misoprostol (7.7 +/- 2.8 h against 14.3 +/- 4.8 h with oxytocin) but the rates of vaginal delivery, cesarean, neonatal outcome variables were similar. Hence, misoprostol is an effective agent for induction of labor at term.
Collapse
|
233
|
Singh VK, Jia Z. Refolding and one-step purification of recombinant human ARA70 over-expressed in Escherichia coli. Protein Expr Purif 2005; 39:283-7. [PMID: 15642480 DOI: 10.1016/j.pep.2004.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Revised: 11/03/2004] [Indexed: 11/29/2022]
Abstract
Androgen receptor (AR)-associated coregulator 70 (ARA70) is a cytoplasmic protein that has been characterized to have the ability to induce AR transcriptional activity in response to androgens and anti-androgens in prostate cancer cells. AR has been shown to have an important role in the progression of prostate cancer and in normal male reproductive system development. To elucidate the molecular mechanisms and biological relevance of ARA70 to prostrate cancer using a variety of biochemical analyses, the cDNA encoding full length ARA70 was cloned into pET21b vector. Here, we report the refolding and one-step purification of ARA70 from inclusion bodies over-expressed in Escherichia coli. The protein was purified to homogeneity, yielding approximately 60 mg ARA70 from 1L of terrific broth media. Refolding process of ARA70 was monitored using far-UV CD analysis.
Collapse
|
234
|
Singh VK, Sai Kumar G, Paliwal OP. Detection of classical swine fever virus in archival formalin-fixed tissues by reverse transcription-polymerase chain reaction. Res Vet Sci 2004; 79:81-4. [PMID: 15894029 DOI: 10.1016/j.rvsc.2004.11.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2003] [Revised: 10/28/2004] [Accepted: 11/04/2004] [Indexed: 11/21/2022]
Abstract
Classical swine fever (CSF) is an economically important Office International des Epizooties list A disease of swine. Inadequate diagnostic infrastructure in developing countries may sometimes make the conduit of viable samples to diagnostic laboratories difficult and at times formalin-fixed tissues may be the only morbid materials available which are not amenable to most laboratory tests. The potential diagnostic abilities in such situations would be enhanced if a highly sensitive and specific method as reverse transcription-polymerase chain reaction (RT-PCR) could be applied to such samples. In the present study, archival formalin-fixed CSF samples were subjected to successful RT-PCR amplification of a 172-bp fragment from E2/NS2 region of CSFV genome. The fidelity of amplification was established by a dot-blot hybridization assay employing a homologous biotinylated cDNA probe. The optimized procedure may be resorted to as a diagnostic tool if viable samples are unavailable and may have the potential to facilitate retrospective studies on archival samples.
Collapse
|
235
|
Singh VK, Seed TM, Kumar KS. N‐Palmitoylation of the Radioprotective Domain of Interleukin‐1 Affords Inhibition of LPS‐Induced Nitric Oxide Generation. Immunopharmacol Immunotoxicol 2004; 26:193-202. [PMID: 15209355 DOI: 10.1081/iph-120037714] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Interleukin-1beta (IL-1beta), a cytokine involved in homeostatic processes such as the immune system and inflammatory reactions, is a potent inducer of nitric oxide. The nonapeptide of human IL-1beta (VQGEESNDK, position 163-171, specific radioprotective domain--SRD) has been shown to retain radioprotective, immunostimulatory, and adjuvant activities of the native molecule without any inflammatory and pyrogenic properties. Unlike the parent IL-1, SRD did not induce nitric oxide (NO) in control or irradiated RAW 264.7 cells nor did it affect inducible nitric oxide synthase (iNOS) as shown by ELISA based mRNA assay (Quantikine). A lipophillic derivative of the SRD (a palmitoyl residue at the amino terminus of the SRD) was synthesized (palmitoyl specific radioprotective domain, P-SRD) to find out if this structural derivatization would restore the NO-inducing ability of IL-1. Surprisingly, P-SRD not only did not induce NO, but significantly inhibited lipopolysaccharide (LPS) stimulated nitric oxide (NO) production. Quantikine studies indicated that P-SRD also inhibited iNOS in LPS stimulated macrophage cells, suggesting that decrease in NO production in the presence of P-SRD was the result of iNOS mRNA inhibition. These results indicate that N-palmitoylation of SRD may effectively ameliorate potentially fatal symptoms of LPS-induced endotoxemic hypotensive shock associated with IL-1 without inflammatory and pyrogenic toxic side effects.
Collapse
|
236
|
Ye Q, Singh VK, Blonde JD, Jia Z. Crystallization and preliminary X-ray analysis of the GST-fused human Bri3 N-terminal domain. Acta Crystallogr Sect F Struct Biol Cryst Commun 2004; 61:62-4. [PMID: 16508092 PMCID: PMC1952390 DOI: 10.1107/s1744309104026739] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2004] [Accepted: 10/21/2004] [Indexed: 11/11/2022]
Abstract
Bri3 is a recently identified proline-rich transmembrane polypeptide up-regulated during TNF-mediated inflammation and immunity. The polyproline-rich N-terminal (residues 1-60) domain of Bri3 was affinity-purified to homogeneity as a glutathione-S-transferase (GST) fusion protein. Crystals were obtained in approximately 3 d by the equilibrium vapour-diffusion method from a solution containing 1.5-2.2 M ammonium sulfate and 0.1 M bis-tris pH 6.0. The crystals belong to space group P4(3)2(1)2, with unit-cell parameters a = b = 91.66, c = 57.53 A. An X-ray data set was collected to 1.6 A resolution using synchrotron radiation, with an Rsym of 0.058 and a completeness of 95.3%. There is one molecule of the fusion protein in the asymmetric unit, which corresponds to approximately 35% solvent content.
Collapse
|
237
|
Tripathi SM, Singh VK, Singh S, Singh DK. Enzyme inhibition by the molluscicidal agent Punica granatum Linn. bark and Canna indica Linn. root. Phytother Res 2004; 18:501-6. [PMID: 15305305 DOI: 10.1002/ptr.1168] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Sublethal in vivo 24 h exposure to (40% and 80% of 24 h LC(50)) active fractions of Punica granatum bark or Canna indica root or in combination with other plant-derived molluscicides significantly inhibited the activity of acetylcholinesterase, acid/alkaline phosphatase, Na(+)K(+)ATPase and lactic dehydrogenase in the nervous tissue of Lymnaea acuminata. The inhibition kinetics of these enzymes indicates that active fractions of both the plants caused a competitive inhibition of AChE, LDH, ALP, ACP and Na(+)K(+)ATPase.
Collapse
|
238
|
Sunder KS, Shetty N, Singh VK, Chaudhary VS, Sharma S. Laser range finder can cause retinal injury. Indian J Ophthalmol 2004; 52:169-70. [PMID: 15283228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023] Open
|
239
|
|
240
|
Mathur V, Singh VK. Phacoemulsification : our experience at a large Military Hospital. Med J Armed Forces India 2004; 60:11-4. [PMID: 27407569 DOI: 10.1016/s0377-1237(04)80149-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cataract surgery by means of phacoemulsification was started at a large Military Hospital in March 2001. First 70 cases in whom phacoemulsification was performed between 15 March 2001 and 31 December 2001 were followed-up and evaluated. The surgical techniques used, complications and post-operative recovery following this new surgical technique have been discussed. Our experience of conversion from standard extracapsular cataract extraction to phacoemulsification has also been shared.
Collapse
|
241
|
Utaida S, Dunman PM, Macapagal D, Murphy E, Projan SJ, Singh VK, Jayaswal RK, Wilkinson BJ. Genome-wide transcriptional profiling of the response of Staphylococcus aureus to cell-wall-active antibiotics reveals a cell-wall-stress stimulon. MICROBIOLOGY-SGM 2003; 149:2719-2732. [PMID: 14523105 DOI: 10.1099/mic.0.26426-0] [Citation(s) in RCA: 258] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The molecular events following inhibition of bacterial peptidoglycan synthesis have not been studied extensively. Previous proteomic studies have revealed that certain proteins are produced in increased amounts upon challenge of Staphylococcus aureus with cell-wall-active antibiotics. In an effort to further those studies, the genes upregulated in their expression in response to cell-wall-active antibiotics have been identified by genome-wide transcriptional profiling using custom-made Affymetrix S. aureus GeneChips. A large number of genes, including ones encoding proteins involved in cell-wall metabolism (including pbpB, murZ, fmt and vraS) and stress responses (including msrA, htrA, psrA and hslO), were upregulated by oxacillin, D-cycloserine or bacitracin. This response may represent the transcriptional signature of a cell-wall stimulon induced in response to cell-wall-active agents. The findings imply that treatment with cell-wall-active antibiotics results in damage to proteins including oxidative damage. Additional genes in a variety of functional categories were upregulated uniquely by each of the three cell-wall-active antibiotics studied. These changes in gene expression can be viewed as an attempt by the organism to defend itself against the antibacterial activities of the agents.
Collapse
|
242
|
Narayan P, Pandey R, Yadav VS, Tandon R, Haq W, Dhar MM, Singh VK. Inhibition of anti-CD3 and interleukin-2 stimulated T lymphocyte proliferation by peptidomimetic opioid compound. Immunopharmacol Immunotoxicol 2003; 25:225-33. [PMID: 12784915 DOI: 10.1081/iph-120020472] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In continuation to our earlier studies with peptidomimetic opioid compounds, we have further investigated immunosuppressive properties of one of our peptidomimetic compound (Tyr-NH-CH2-CH2-O-Phe-NH2) using peripheral blood mononuclear cells (PBMCs) of healthy volunteers. Peptidomimetic compound was evaluated for its effect on anti-CD3 and recombinant human interleukin-2 (rhIL-2) stimulated lymphocyte proliferation in vitro and lipopolysaccharide (LPS) induced activation of mitogen activated protein kinase (MAPK, pp42/44) in mouse macrophage cells (RAW 264.7). Our results show the immunosuppressive potential of synthetic peptidomimetic compound. This compound significantly inhibited anti-CD3 and rhIL-2 stimulated lymphocyte proliferation in vitro. However, this peptidomimetic compound did not show any effect on LPS induced MAPK activation. These observations suggest that above peptidomimetic compound has potential to inhibit immune responses mediated by lymphocytes.
Collapse
|
243
|
Rao BK, Pande R, Sharma SC, Ray S, Lakshmi B, Singh VK, Gupta RK, Suri S. Percutaneous tracheostomy. Ann Card Anaesth 2003; 6:19-26. [PMID: 17827587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023] Open
Abstract
The purpose of this review is to discuss the various techniques of percutaneous tracheostomy and to assess their safety and efficacy profile, indications and contraindications, early and late complications. Literature was reviewed from Medline and MD Consult databases. Early techniques by Sheldon, toye and Schachner have been abandoned due to their high complication rates. Percutaneous dilational tracheostomy using the Ciaglia kit (Wiliam Cook Europe Bjaeverskov) and a Griggs kit (Portex PDT kit, POrtex, Hythe, Kent, UK) has been used most often. Griggs guide Wire Dilator Forceps kit (SIMS, Portex, Hythe, Kent, UK) is the next most common in use but its long-term studies are few. Fantoni (TLT set, Mallinckrodt Medical) and PercuTwist device (Riisch, Kernen, Germany) are two new techniques currently under study. Percutaneous dilational tracheostomy and conventional surgical tracheostomy are still competing methods to provide an airway for intensive care patient requiring assisted ventilation. Review of literature shows that percutaneous tracheostomy is safe, cost-effective and compares favourably with the open surgical tracheostomy. Many intensive care units now use the percutaneous tracheostomy as a procedure of choice. Percutaneous tracheostomy has a learning curve and requires appropriate case selection and meticulous attention to the technique by all those who want to use this method.
Collapse
|
244
|
Mehrotra S, Mishra KP, Maurya R, Srimal RC, Yadav VS, Pandey R, Singh VK. Anticellular and immunosuppressive properties of ethanolic extract of Acorus calamus rhizome. Int Immunopharmacol 2003; 3:53-61. [PMID: 12538034 DOI: 10.1016/s1567-5769(02)00212-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Modulation of immune response to alleviate disease has been of interest since long. Plant extracts have been widely investigated for possible immunomodulatory properties. We have evaluated the anticellular and immunomodulatory properties of ethanolic extract of Acorus calamus rhizome. This extract inhibited proliferation of mitogen (phytohaemagglutinin; PHA) and antigen (purified protein derivative; PPD)-stimulated human peripheral blood mononuclear cells (PBMCs). In addition, A. calamus extract inhibited growth of several cell lines of mouse and human origin. It also inhibited production of nitric oxide (NO), interleukin-2 (IL-2) and tumor necrosis factor-alpha (TNF-alpha). Intracytoplasmic interferon-gamma (IFN-gamma) and expression of cell surface markers, CD16 and HLA-DR, on human PBMC, were not affected on treatment with A. calamus extract but CD25 expression was down regulated. Our study demonstrates the antiproliferative and immunosuppressive potential of ethanolic extract of A. calamus rhizome in vitro.
Collapse
|
245
|
Rao IG, Singh A, Singh VK, Singh DK. Effect of single and binary combinations of plant-derived molluscicides on different enzyme activities in the nervous tissue of Achatina fulica. J Appl Toxicol 2003; 23:19-22. [PMID: 12518332 DOI: 10.1002/jat.874] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Effect of single and binary treatments of plant-derived molluscicides on different enzymes--acetylcholinesterase (AChE), lactic dehydrogenase (LDH) and acid/alkaline phosphatase (ACP/ALP)--in the nervous tissue of the harmful terrestrial snail Achatina fulica were studied. Sublethal in vivo 24-h exposure to 40% and 80% LC(50) of Azadirachta indica oil, Cedrus deodara oil, Allium sativum bulb powder, Nerium indicum bark powder and binary combinations of A. sativum (AS) + C. deodara (CD) and CD + A. indica (AI) oils significantly altered the activity of these enzymes in the nervous tissue of Achatina fulica. The binary treatment of AS + CD was more effective against AChE, LDH, and ALP than the single ones. However, binary treatment of AI + CD was more effective against ALP.
Collapse
|
246
|
Gugnani HC, Sehgal VN, Singh VK, Boiron P, Kumar S. 'Nocardia asteroides' mycetoma of the foot. J Eur Acad Dermatol Venereol 2002; 16:640-2. [PMID: 12482056 DOI: 10.1046/j.1468-3083.2002.00653_3.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
247
|
Mehrotra S, Mishra KP, Maurya R, Srimal RC, Singh VK. Immunomodulation by ethanolic extract of Boerhaavia diffusa roots. Int Immunopharmacol 2002; 2:987-96. [PMID: 12188040 DOI: 10.1016/s1567-5769(02)00031-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We have earlier reported that ethanolic extract of Boerhaavia diffusa, a plant used in Indian traditional system of medicine, significantly inhibits the cell proliferation. This led us to evaluate the immunomodulatory properties of this plant extract on various in vitro tests such as human natural killer (NK) cell cytotoxicity, production of nitric oxide (NO) in mouse macrophage cells, RAW 264.7, interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha), intracytoplasmic interferon-gamma (IFN-gamma) and expression of various cell surface markers on human peripheral blood mononuclear cells (PBMCs). Ethanolic extracts of B. diffusa roots inhibited human NK cell cytotoxicity in vitro, production of NO in mouse macrophage cells, IL-2 and TNF-alpha in human PBMCs. Intracytoplasmic IFN-gamma and cell surface markers such as CD16, CD25, and HLA-DR did not get affected on treatment with B. diffusa extract. Our study demonstrates immunosuppressive potential of ethanolic extract of B. diffusa.
Collapse
|
248
|
Mehrotra S, Singh VK, Agarwal SS, Maurya R, Srimal RC. Antilymphoproliferative activity of ethanolic extract of Boerhaavia diffusa roots. Exp Mol Pathol 2002; 72:236-42. [PMID: 12009788 DOI: 10.1006/exmp.2002.2427] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Extracts of plants have been widely evaluated for possible antiproliferative and anticarcinogenic properties. The antiproliferative activity of ethanolic extract of Boerhaavia diffusa, a plant used in traditional medicine, was evaluated in several cells. It inhibited T cell mitogen phytohemagglutinin and concanavalin A-stimulated proliferation of human peripheral blood mononuclear cells (PBMC). It also inhibited purified protein derivative antigen-stimulated PBMC proliferation and human mixed lymphocyte culture. In addition, B. diffusa extract inhibited the growth of several cell lines of mouse and human origin, such as mouse macrophage cells (RAW 264.7), human macrophage cells (U937), human monocytic cells (THP-1), mouse fibroblast cells (L929), human embryonic kidney cells (HEK293), mouse liver cells (BNLCL.2), African green monkey kidney cells (COS-1), mouse lymphoma cells (EL-4), human erythroleukemic cells (K562), and human T cells (Jurkat). The present study has demonstrated the antiproliferative potential of ethanolic extract of B. diffusa in vitro.
Collapse
|
249
|
Narayan P, Tandon R, Haq W, Dhar MM, Singh VK. Inhibition of antigen specific lymphocyte proliferation and cytokine stimulation by peptidomimetic opioid compound. Int Immunopharmacol 2002; 2:751-7. [PMID: 12095165 DOI: 10.1016/s1567-5769(02)00011-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In sequel to our preliminary observations with peptidomimetic opioid compounds, we have further investigated immunomodulatory activity of one peptidomimetic compound (Tyr-NH-CH2-CH2-O-Phe-NH2) with peripheral blood mononuclear cells (PBMCs) of healthy volunteers/tuberculosis patients. This peptidomimetic compound was evaluated for its effect on purified protein derivative (PPD) stimulated lymphocyte proliferation in vitro, production of Th1 and Th2 cytokines by ELISA and ribonuclease protection assay. Our study shows the immunosuppressive potential of above synthetic peptidomimetic compound. This compound inhibited PPD stimulated human lymphocyte proliferation and this inhibition was reversed by opioid receptor antagonist, naloxone. Its immunosuppressive effect was further demonstrated by inhibition of interleukin-9 (IL-9), IL-10 but failed to influence IL-2, IL-15 and interferon-y (IFN-gamma) in PPD stimulated human PBMCs.
Collapse
|
250
|
Mehrotra S, Prajapati RK, Haq W, Singh VK. Immunomodulation by biphalin, dimeric synthetic opioid peptide, and its analog. Immunopharmacol Immunotoxicol 2002; 24:83-96. [PMID: 12022447 DOI: 10.1081/iph-120003405] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The opioid pentapeptides called enkephalins were originally described as the endogenous ligands for the opioid receptors. Although their precise physiological significance still remains elusive, the enkephalins have been reported to exhibit analgesic, antidepressant, antianxiety and anticonvulsant activities. In addition, enkephalins have also been shown to act as immunomodulator. The first generation of dimeric peptides was derived from enkephalins. Biphalin [(Tyr-D-Ala-Gly-Phe-NH)2] is a bivalent opioid analog containing two tyrosine residues. We have evaluated the immunomodulatory properties of biphalin and its analogs in various in vitro tests. We report that biphalin and one of its analogs [Tyr-D-Ala-Gly-Phe-NH.NH-Phe(p-Cl)-H] stimulate human T cell proliferation, natural killer (NK) cell cytotoxicity in vitro and interleukin-2 (IL-2) production. Biphalin and its analog also released chemokine like factor in the culture supernatant that was responsible for increased chemotaxis of monocytes. Furthermore, these peptides inhibited tumor necrosis factor (TNF-alpha) production in lipopolysaccharide (LPS) stimulated peripheral blood mononuclear cells (PBMC) and nitric oxide (NO) production in mouse macrophage cells, RAW 264.7. Our observations suggest immunomodulatory property of biphalin and its analog.
Collapse
|