Immunomodulatory effects of curcumin

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.

Identification of an ITPase/XTPase in Escherichia coli by structural and biochemical analysis

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.

Misoprostol vs. oxytocin for induction of labor at term

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.

Refolding and one-step purification of recombinant human ARA70 over-expressed in Escherichia coli

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.

Detection of classical swine fever virus in archival formalin-fixed tissues by reverse transcription-polymerase chain reaction

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.

N‐Palmitoylation of the Radioprotective Domain of Interleukin‐1 Affords Inhibition of LPS‐Induced Nitric Oxide Generation

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.

Crystallization and preliminary X-ray analysis of the GST-fused human Bri3 N-terminal domain

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.

Enzyme inhibition by the molluscicidal agent Punica granatum Linn. bark and Canna indica Linn. root

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.

Phacoemulsification : our experience at a large Military Hospital

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.

Genome-wide transcriptional profiling of the response of Staphylococcus aureus to cell-wall-active antibiotics reveals a cell-wall-stress stimulon

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.

Inhibition of anti-CD3 and interleukin-2 stimulated T lymphocyte proliferation by peptidomimetic opioid compound

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.

Percutaneous tracheostomy

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.

Anticellular and immunosuppressive properties of ethanolic extract of Acorus calamus rhizome

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.

Effect of single and binary combinations of plant-derived molluscicides on different enzyme activities in the nervous tissue of Achatina fulica

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.

Immunomodulation by ethanolic extract of Boerhaavia diffusa roots

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.

Antilymphoproliferative activity of ethanolic extract of Boerhaavia diffusa roots

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.

Inhibition of antigen specific lymphocyte proliferation and cytokine stimulation by peptidomimetic opioid compound

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.

Immunomodulation by biphalin, dimeric synthetic opioid peptide, and its analog

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.

Cytokines in posterior uveitis: an update

T helper (Th) lymphocytes differentiate into two distinct subsets--Th1 and Th2--as defined by functional abilities and cytokine profiles. The functional differences between Th subsets are explained primarily through the activities of the cytokines they secrete. Interferon-gamma (IFN-gamma) is the signature cytokine of Th1 cells, which also produce interleukin-2 (IL-2) and tumor necrosis factor-beta (TNF-beta). IL-4 is the corresponding signature cytokine of Th2 cells, which also secrete IL-5, IL-6, IL-9, and IL-13. Recently, a few transcription factors have been identified that not only control the expression of cytokines of a particular type but also repress cytokines of other types. Human Th1 and Th2 cells not only produce a different set of cytokines but also exhibit distinct functional properties and the preferential expression of some activation markers. Pathophysiologically, the two subsets have been found to be mutually antagonistic. Various Th1 and Th2 cytokines appear to play an important role in the etiopathogenesis of posterior uveitis and its animal model, experimental autoimmune uveitis (EAU). The exact contribution of these mediators to uveitis remains to be defined. Recent studies suggest that a shift from Th1- to Th2-dominated response could be of therapeutic benefit. This review evaluates various studies in which uveitopathogenic and therapeutic potentials of various Th1 and Th2 cytokines have been investigated.

Molecular characterization of a chromosomal locus in Staphylococcus aureus that contributes to oxidative defence and is highly induced by the cell-wall-active antibiotic oxacillin

Previous studies employing two-dimensional gel electrophoresis and N-terminal protein sequencing have shown elevated synthesis of the enzyme methionine sulfoxide reductase (MsrA) in Staphylococcus aureus in response to cell-wall-active antibiotics. In the present study, the S. aureus msrA gene was cloned, overexpressed, purified as His-tagged MsrA and shown to have methionine sulfoxide reductase activity. The transcription of msrA was studied by assaying beta-galactosidase activity in an msrA promoter::lacZ fusion strain and by Northern blot analysis. Transcription of msrA was increased by oxacillin; but not by a variety of other stresses including H2O2. Northern blot analysis revealed that the size of the msrA transcript was 2.3 kb, considerably larger than the 531 nt msrA ORF. The msrA transcription start site was mapped 25 nt upstream of the msrA start codon. Computer analysis from database sequences indicated at least three additional ORFs downstream of msrA. The deduced amino acid sequences of two of these three ORFs showed significant sequence homologies to PilB, and enzyme IIA of the phosphotransferase system, respectively. The third ORF could not be identified by homology searches. Northern blot hybridization with probes specific to the msrA downstream region indicated that the S. aureus msrA was transcribed as part of a polycistronic message. Interestingly, purified S. aureus PilB was shown to possess approximately approximately 28-fold higher methionine sulfoxide reductase activity than the MsrA. An insertional knockout mutation in the first gene of this operon resulted in increased susceptibility of the mutant to H2O2 compared to the parent strain, but not to oxacillin.