Influence of age and sex on levels of anti-oxidized LDL antibodies and anti-LDL immune complexes in the general population

Most studies of antibodies to oxidized LDL have been undertaken in patients with different diseases and cardiovascular risk factors. However, very few studies have researched the distribution and determining factors of antibodies to oxidized LDL in the general population. A total of 1,354 persons (817 females and 537 males) aged 5-65 years were included in this study. They were selected randomly from the population census of Málaga, in southern Spain. The females had lower levels of total cholesterol and triglycerides and higher levels of HDL-cholesterol and a very significant increase (P < 0.0001) in levels of anti-oxidized LDL [low density lipoprotein modified by malondialdehyde (MDA-LDL)] antibodies but no difference in levels of immune complexes consisting of LDL and IgG antibodies (anti-LDL immune complex). Younger persons (16-35 years) had higher levels of anti-oxidized LDL (MDA-LDL) antibodies than persons older than 35 years (P = 0.05). Levels of immune complexes were significantly higher (P = 0.05) in persons aged 5-15 years than in persons older than 40 years. A very weak association was found between levels of anti-oxidized LDL (MDA-LDL) antibodies and anti-LDL immune complexes. The higher prevalence of anti-oxidized LDL (MDA-LDL) antibodies in females and young persons is in agreement with studies that found an inverse association between atherosclerosis and the level of these antibodies.     

A single-chain antibody/epitope system for functional analysis of protein-protein interactions

Protein-protein interactions play a critical role in cellular processes such as signal transduction. Although many methods for identifying the binding partners of a protein of interest are available, it is currently difficult or impossible to assess the functional consequences of a specific interaction in vivo. To address this issue, we propose to modify proteins by addition of an artificial protein binding interface, thereby forcing them to interact in the cell in a pairwise fashion and allowing the functional consequences to be determined. For this purpose, we have developed an artificial binding interface consisting of a anti-Myc single-chain antibody (ScFv) and its peptide epitope. We found that the binding of an ScFv derived from anti-Myc monoclonal antibody 9E10 was relatively weak in vivo, so we selected an improved clone, 3DX, by in vitro mutagenesis and phage display. 3DX bound well to its epitope in a yeast two-hybrid system, and GST-fused 3DX also bound to several Myc-tagged proteins in mammalian cells. In vivo binding was relatively insensitive to the position of the ScFv in a fusion protein, but was improved by including multiple tandem copies of the Myc epitope in the binding partner. To test the system, we successfully replaced the SH3 domain-mediated interaction between the Abl tyrosine kinase and adaptor proteins Crk and Nck with an engineered interaction between 3DX and multiple Myc tags. We expect that this approach, which we term a functional interaction trap, will be a powerful proteomic tool for investigating protein-protein interactions.     

Cloning of S4D-SRCRB,a new soluble member of the group B scavenger receptor cysteine-rich family (SRCR-SF) mapping to human chromosome 7q11.23

The scavenger receptor cysteine-rich superfamily (SRCR-SF) is a highly conserved group of membrane and/or secreted proteins related to the innate and adaptive immune system. Here, we report the cloning of the gene encoding human S4D-SRCRB, a novel soluble member of the SRCR-SF, which is composed of four group B SRCR domains separated by Pro-, Ser- and Thr-rich polypeptides. The longest cDNA sequence found is 2,806 bp in length and encodes a mature protein of 528 aa, with a predicted molecular mass of M(r) 55,600. The S4D-SRCRB gene is located at Chromosome 7q11.23, telomeric to the Williams-Beuren syndrome deletion. It extends over 20 kb and consists of 11 exons, with each SRCR domain being encoded by a single exon. Northern blot analysis indicated that S4D-SRCRB has a broad tissue distribution and is expressed as two major mRNA species: one of 2.8 kb, with a restricted tissue expression pattern (mainly kidney and placenta), and another of 1.5 kb, with a broader distribution. A similar mRNA expression pattern was observed during the analysis of several tumor cell lines. The highest degree of similarity found between S4D-SRCRB and other group B SRCR-SF members was with human DMBT1 (a mosaic protein composed of fourteen SRCR domains, which is involved in innate defense and epithelia polarization) and chicken 18-B (a turpentine-induced soluble acute-phase protein composed of four SRCR domains). Our data indicate that S4D-SRCRB constitutes a novel SRCR-SF member, which could be involved in basic homeostatic functions such as innate host defense.     

The effects of oral glutamine on cisplatin-induced genotoxicity in Wistar rat bone marrow cells

Several studies have suggested that dietary supplementation with antioxidants can influence the response to chemotherapy as well as the development of adverse side effects that result from treatment with antineoplastic agents. The emphasis of the present study was to investigate whether the administration of a single dose of oral glutamine had any protective effect against cisplatin-induced clastogenicity. Cisplatin was administered to Wistar rats either alone or after treatment with glutamine. The rats were treated with glutamine (300 mg/kg b.w.) by gavage 24h before the administration of cisplatin (5mg/kg b.w., i.p.) and then sacrificed 24h after treatment with cisplatin. Glutamine significantly reduced (by about 48%) the clastogenicity of cisplatin in rat bone marrow cells. The antioxidant action of glutamine presumably modulates the clastogenic action of cisplatin.     

DNA Interaction and photonicking properties of DNA-targeted acridine (2,2'-Bipyridine)platinum(II) complexes

Synthesis of two (2,2'-bipyridine)platinum(II) complexes tethered to one or two acridine chromophores is reported. These acridine complexes efficiently unwind and photocleave supercoiled plasmid DNA under physiological conditions of temperature and pH.     

Intensity of inflammation, density of colonization and interleukin-8 response in the gastric mucosa of children infected with Helicobacter pylori

Background. Few reports exist on inflammation and interleukin (IL)‐8 response in H. pylori‐infected children. The aim of this study was to determine the intensity of inflammation, density of colonization and magnitude of IL‐8 response in children with and without H. pylori infection. Materials and Methods. We studied 45 children with dyspeptic symptoms, 21 infected with H. pylori and 24 without infection. Antrum and corpus gastric biopsies were obtained and studied for H. pylori infection with an immunofluorescence technique and for IL‐8 with an immunohistochemical assay. Biopsy specimens were stained with hematoxilin and eosin and gastritis was graded according to the Sydney system. The magnitudes of the IL‐8 response and H. pylori colonization were estimated microscopically with image analyzer software. Results. In H. pylori‐infected children, mild mono^‐nuclear cell infiltration was found in 50%, and no neutrophils in 40% of cases. In the antrum but not in the corpus, the intensity of colonization correlated with neutrophil and mononuclear cell infiltration. The IL‐8 response was significantly higher in the antrum (p < .05) and corpus (p < .02) of infected children, and was localized mainly in the surface and crypts of the epithelium. No correlation was found between the magnitude of the IL‐8 response and the infiltration of either neutrophil or mononuclear cells. Conclusions. In H. pylori‐infected children, poor mononuclear and neutrophil infiltration was observed. Infection was associated with a higher IL‐8 response by gastric epithelial cells. The density of colonization but not the IL‐8 response correlated with neutrophil cell infiltration.     

Expression of p53 in luminal and glandular epithelium during the growth and regression of rat uterus during the estrous cycle

It has been well recognized that epithelial cells of the rat endometrium cyclically proliferate and die during the estrous cycle. The aim of the present study was to determine p53 expression pattern and correlate it with the the apoptotic pattern of epithelial cells of the rat uterus during the estrous cycle. The p53 mRNA and protein expression pattern was assessed by in situ hybridization and immunohistochemistry. The apoptotic index was determined by using terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) and electron microscopy. The highest p53 mRNA content, detected by in situ hybridization, was observed on the metestrus day both in the luminal and the glandular epithelia. During this period both epithelia presented high proliferation. The content of p53 mRNA markedly decreased in the following days, presenting its minimal values on the estrus day. The highest number of p53 immunopositive nuclei, in both the luminal and the glandular epithelia, was also detected on the metestrus day, while the lowest one was found on estrus day. On the proestrus day, p53 protein was predominantly detected in the glandular epithelium. However, on the estrus day, p53 protein was detected both in the nuclei and in the cytoplasm of luminal epithelial cells, predominantly in the cytoplasm. The highest apoptotic index in both the luminal and the glandular epithelia was observed on the estrus day whereas the lowest one was observed on the proestrus day. The apoptotic index values were higher in the luminal than in the glandular epithelia. The overall results indicate that p53 expression at both mRNA and protein levels is higher on the metestrus day when the apoptotic index is low. This suggests that p53 should play an important physiological role during proliferative phases of the estrous cycle in the rat uterus.