Variation of plasma levels of endothelin, calcitonin gene-related peptide, nitric oxide, and malondialdehyde in acute myocardial ischemia reperfusion injury in a rabbit model.

We examined the variation in plasma levels of endothelin (ET), calcitonin gene-related peptide (CGRP), nitric oxide (NO), and malondialdehyde (MDA), as well as superoxide dismutase (SOD) activity, in acute myocardial ischemia reperfusion injury in a rabbit model. Seventy rabbits were randomly assigned into 3 groups. Open-chest surgery (OCS) was performed for all rabbits. Group A (N = 20) received sham-surgery, group B (N = 25) was the reperfusion group, and group C (N = 25) was the infarction group. At 12 h after chest clo-sure, plasma ET levels in groups B and C were clearly increased, while CGRP levels were clearly decreased, particularly in group B. At 24 h after chest closure, ET levels were higher than before OCS, while there was no significant difference between groups B and C. ET in group B was decreased, while that in group C was increased at 12 h. No significant difference in CGRP was observed between 12 and 24 h after chest closure. NO levels in groups B and C at 12 h after chest closure were significantly decreased compared to those before OCS. NO levels in group B at 24, 48, and 72 h were significantly lower than those at 12 h, while those of group C were not significantly changed after 12 h. Dynamic monitoring and comparison of plasma levels of ET, CGRP, NO, and MDA as well as SOD activity revealed that appropriate intervention of these factors may reduce reperfusion injury.

Expression, production, and renaturation of a functional single-chain variable antibody fragment (scFv) against human ICAM-1

Intercellular adhesion molecule-1 (ICAM-1) is an important factor in the progression of inflammatory responses in vivo. To develop a new anti-inflammatory drug to block the biological activity of ICAM-1, we produced a monoclonal antibody (Ka=4.19×10−8 M) against human ICAM-1. The anti-ICAM-1 single-chain variable antibody fragment (scFv) was expressed at a high level as inclusion bodies in Escherichia coli. We refolded the scFv (Ka=2.35×10−7 M) by ion-exchange chromatography, dialysis, and dilution. The results showed that column chromatography refolding by high-performance Q Sepharose had remarkable advantages over conventional dilution and dialysis methods. Furthermore, the anti-ICAM-1 scFv yield of about 60 mg/L was higher with this method. The purity of the final product was greater than 90%, as shown by denaturing gel electrophoresis. Enzyme-linked immunosorbent assay, cell culture, and animal experiments were used to assess the immunological properties and biological activities of the renatured scFv.

Expression, production, and renaturation of a functional single-chain variable antibody fragment (scFv) against human ICAM-1.

Intercellular adhesion molecule-1 (ICAM-1) is an important factor in the progression of inflammatory responses in vivo. To develop a new anti-inflammatory drug to block the biological activity of ICAM-1, we produced a monoclonal antibody (Ka=4.19 × 10(-8) M) against human ICAM-1. The anti-ICAM-1 single-chain variable antibody fragment (scFv) was expressed at a high level as inclusion bodies in Escherichia coli. We refolded the scFv (Ka=2.35 × 10(-7) M) by ion-exchange chromatography, dialysis, and dilution. The results showed that column chromatography refolding by high-performance Q Sepharose had remarkable advantages over conventional dilution and dialysis methods. Furthermore, the anti-ICAM-1 scFv yield of about 60 mg/L was higher with this method. The purity of the final product was greater than 90%, as shown by denaturing gel electrophoresis. Enzyme-linked immunosorbent assay, cell culture, and animal experiments were used to assess the immunological properties and biological activities of the renatured scFv.

The isolation, localization and characterization of the QM homolog in Drosophila melanogaster.

A fragment of 443 bp was amplified from a lambda ZAPII Drosophila central nervous system (CNS) cDNA library using minimally degenerate primers to very conserved regions of the QM gene. This fragment was used as a probe to screen the lambda ZAPII Drosophila CNS cDNA library. Two clones of the Drosophila QM homolog (pDQM-7A1 and pDQM-2B1), each containing the complete coding region, were isolated. The 5'-UTR of this gene was obtained by RACE PCR and ligated to the coding sequence to produce a the full-length copy of the Drosophila QM homolog (DQM) cDNA. The DQM cDNA measures 746 nucleotides in length and encodes a polypeptide of 218 residues. The amino acid sequence shows 76.1 percent identity with human QM and 69.1 percent identity with QSR1, the yeast homolog of QM. Unlike the human or mouse genome which contains multiple copies of the QM gene, the Drosophila genome has only a single copy as indicated by genomic Southern blot analysis. In situ hybridization confirms the presence of a single copy of DQM in the Drosophila genome and localizes it to the left arm of the third chromosome at the end of region 80A (80A-4).