Wound healing activity of NOE-aspirin: a pre-clinical study.

Aspirin, one of the oldest non-steroidal anti-inflammatory drugs, impedes tissue repair by virtue of retarding inflammation. The present study was undertaken to find out if linking of nitrooxyethyl ester to aspirin reverses its healing-depressant propensity. Nitrooxyethyl ester of aspirin (NOE-Asp) was synthesized in our laboratory through well-established synthetic pathway, starting from aspirin through esterification with ethylene glycol and nitration with a mixture of nitric and sulfuric acids at 0 degrees C. The effect of NOE-Asp on phases of healing such as collagenation, wound contraction and epithelialization and on scar size of healed wound was evaluated in three wound models-incision, dead space, and excision wounds. To assess its influence on the oxidative stress, the levels of glutathione (GSH) and thiobarbiturate reactive species (TBARS) were also determined in 10-day-old granulation tissue. NOE-Asp was further screened for its anti-inflammatory activity in rat paw edema model. NOE-Asp promoted collagenation (increase in breaking strength, granulation weight, and collagen content), wound contraction, and epithelialization phases of healing. NOE-Asp also showed a significant antioxidant effect in 10-day-old granulation tissue as compared to aspirin. The results vindicate our assumption that the esterification of aspirin with nirooxyethyl group reverses the healing-suppressant effect of aspirin. The compound also showed equipotent anti-inflammatory activity as aspirin.     

The phylogeny and evolution of host choice in the Hippoboscoidea (Diptera) as reconstructed using four molecular markers

Hippoboscoidea is a superfamily of Diptera that contains the Glossinidae or tsetse flies, the Hippoboscidae or louse flies, and two families of bat flies, the Streblidae and the Nycteribiidae. We reconstruct the phylogenetic relationships within Hippoboscoidea using maximum parsimony and Bayesian methods based on nucleotide sequences from fragments of four genes: nuclear 28S ribosomal DNA and the CPSase domain of CAD, and mitochondrial 16S rDNA and cytochrome oxidase I. We recover monophyly for most of the presently recognized groups within Hippoboscoidea including the superfamily as a whole, the Hippoboscidae, the Nycteribiidae, the bat flies, and the Pupipara (=Hippoboscidae+Nycteribiidae+Streblidae), as well as several subfamilies within the constituent families. Streblidae appear to be paraphyletic. Our phylogenetic hypothesis is well supported and decisive in that most competing topological hypotheses for the Hippoboscoidea require significantly longer trees. We confirm a single shift from a free-living fly to a blood-feeding ectoparasite of vertebrates and demonstrate that at least two host shifts from mammals to birds have occurred. Wings have been repeatedly lost, but never regained. The hippoboscoid ancestor also evolved adenotrophic viviparity and our cladogram is consistent with a gradual reduction in the motility of the deposited final instar larvae from active burrowing in the soil to true pupiparity where adult females glue the puparium within the confines of bat roosts.     

Identification and characterization of rad51 of Pneumocystis

Rad51, a eukaryotic homolog of RecA, is an important protein involved in DNA recombination and repair. We have characterized rad51 of Pneumocystis carinii and Pneumocystis murina. rad51 is a single copy gene that encodes a 1.2 kb mRNA, which contains an open reading frame encoding 343 amino acids. Rad51 from Pneumocystis showed high homology to those from yeast. ATP binding motifs GEFRTGKS and LLIVD, similar to those of Saccharomyces cerevisiae and Schizosaccharomyces pombe, are conserved in Pneumocystis Rad51. The recombinant protein when expressed in E. coli showed DNA-dependent ATPase activity. Since Rad51 is a key enzyme in DNA repair and recombination, it potentially plays an important role in the recombination process leading to antigenic variation and thereby resistance to host immune responses in Pneumocystis.     

Affinity binding of cells to cryogel adsorbents with immobilized specific ligands: effect of ligand coupling and matrix architecture

The capture of human acute myeloid leukemia KG-1 cells expressing the CD34 surface antigen and the fractionation of human blood lymphocytes were evaluated on polyvinyl alcohol (PVA)-cryogel beads and dimethyl acrylamide (DMAAm) monolithic cryogel with immobilized protein A. The affinity ligand (protein A) was chemically coupled to the reactive PVA-cryogel beads and epoxy-derivatized monolithic cryogels through different immobilization techniques and the binding efficiency of the cell surface receptors specific antibody-labeled cells to the gels/beads was determined. The binding of cells to monolithic cryogel was higher (90-95%) compared with cryogel beads (76%). B-lymphocytes, which bound to the protein A-cryogel beads, were separated from T-lymphocytes with yields for the two cell types 74 and 85%, respectively. About 91% of the bound B-cells could be recovered without significantly impairing their viability. Our results show differences in the percentage of cell-binding to the immunosorbents caused by ligand density, flow shear forces and bond strength between the cells and the affinity surface once distinct chemical coupling of protein A, size of beads, sequence of antibody binding to protein A adsorbents, morphology and geometry of surface matrices were compared.     

Antibody-induced arthritis: disease mechanisms and genes involved at the effector phase of arthritis

During the development of rheumatoid arthritis (RA) autoantibodies to IgG-Fc, citrullinated proteins, collagen type II (CII), glucose 6 phosphoisomerase (G6PI) and some other self-antigens appear. Of these, a pathogenic effect of the anti-CII and anti-G6PI antibodies is well demonstrated using animal models. These new antibody mediated arthritis models have proven to be very useful for studies involved in understanding the molecular pathways of the induction of arthritis in joints. Both the complement and FcgammaR systems have been found to play essential roles. Neutrophils and macrophages are important inflammatory cells and the secretion of tumour necrosis factor-alpha and IL-1beta is pathogenic. The identification of the genetic polymorphisms predisposing to arthritis is important for understanding the complexity of arthritis. Disease mechanisms and gene regions studied using the two antibody-induced arthritis mouse models (collagen antibody-induced arthritis and serum transfer-induced arthritis) are compared and discussed for their relevance in RA pathogenesis.     

FTIR spectro-imaging of collagens for characterization and grading of gliomas

Collagens are a family of at least 30 protein types organized as networks. They constitute the main support material of cells under the form of extracellular matrix as well as for membranes in vessels, organs, and tissue compartments. Collagen network abnormalities are at the origin of many diseases, including myopathies and fibroses. The characterization of collagens remains an analytical challenge due to the insolubility of these molecules and the difficulty encountered in isolating given types without altering their structure or in maintaining network organization, which is critical to diagnosing related pathologies. We have proposed using a vibrational spectroscopy based imaging technique, namely Fourier-transform infrared (FTIR) imaging, for a spatially-resolved analysis of secondary structure of different collagen types in complex samples, and more specifically for characterizing gliomas. With newly developed spectral data treatments and chemometrics using secondary structure parameters of collagen proteins, FTIR imaging is now able to distinguish between several types. On this basis, gliomas have been investigated as specific collagen-rich tissues developing in a non-collagenous environment, providing high specificity to this FTIR imaging utilization. Here, we review the recent advances in this imaging approach for understanding glioma development, with FTIR imaging now being proposed as a molecular histopathology tool for clinicians.     

Cartilage oligomeric matrix protein specific antibodies are pathogenic

Introduction

Cartilage oligomeric matrix protein (COMP) is a major non-collagenous component of cartilage. Earlier, we developed a new mouse model for rheumatoid arthritis using COMP. This study was undertaken to investigate the epitope specificity and immunopathogenicity of COMP-specific monoclonal antibodies (mAbs).

Methods

B cell immunodominant regions on the COMP molecule were measured with a novel enzyme-linked immunosorbent assay using mammalian expressed full-length mouse COMP as well as a panel of recombinant mouse COMP fragments. 18 mAbs specific to COMP were generated and the pathogenicity of mAbs was investigated by passive transfer experiments.

Results

B cell immunodominant epitopes were localized within 4 antigenic domains of the COMP but with preferential response to the epidermal growth factor (EGF)-like domain. Some of our anti-COMP mAbs showed interactions with the native form of COMP, which is present in cartilage and synovium. Passive transfer of COMP-specific mAbs enhanced arthritis when co-administrated with a sub-arthritogenic dose of a mAb specific to collagen type II. Interestingly, we found that a combination of 5 COMP mAbs was capable of inducing arthritis in naive mice.

Conclusions

We have identified the specificities of mAbs to COMP and their contribution to the development of arthritis. These findings will further improve our understanding of the autoantibody mediated immunopathologies occurring widely in rheumatoid arthritis (RA), as well as in other autoimmune disorders.     

Length‐weight analysis of three needlefish species from the Lakshadweep archipelago

Length‐weight relationships (LWRs) of three needlefishes belonging to the family Belonidae viz., Ablennes hians, Tylosurus crocodilus and Tylosurus acus melanotus were estimated based on samples exploited from a gill‐net fishery in Androth, an island in the Lakshadweep archipelago. The estimated allometric co‐efficient b value ranged from 3.047 (T. acus melanotus) to 3.274 (A. hians), and r² value ranged from 0.911 (T. acus melanotus) to 0.973 (A. hians). The first estimate of LWR for these three commercially exploited needlefish species from the Lakshadweep islands indicate local populations to be fairly robust and forms a basis for future management of fishing stock in the region.