Chlamydophila pneumoniae, an important respiratory pathogen causing lower respiratory tract infections, has also been implicated in coronary heart disease (CHD). This study reports a cross-sectional, demographic, serological analysis of the prevalence of Chlamydophila pneumoniae antibodies in a multiracial Malaysian population. Generally, Malaysian Indians had the highest degree of seropositivity (58%) followed by the Chinese (54%) and the Malays (32%), results which were statistically significant (CI: 95%; p < 0.01). Interestingly, this trend was also reflected in the study group consisting of patients with acute myocardial infarctions (AMI) and chronic CHD. Again, the Indians were more frequently seropositive (65%), with more than 50% having IgG titres > or = 128. Comparatively, the Chinese and Malays showed 51 and 17% seropositivity respectively. These results were also statistically significant (CI: 95%; p < 0.01). Malaysian Indians are more commonly afflicted with CHD. A variety of factors have been suggested to explain this prevalence including diet, social habits, genetics and the possible role of infectious agents. This study notes an interesting association between this pattern of racial prevalence and the possible role of C. pneumoniae infections as a contributory/predisposing factor in the development of cardiovascular disease.
A series of 122, 9-mer overlapping peptides based on the sequence of the Salmonella typhi GroEL gene was synthesized on the surfaces of polyethylene pins and screened with monoclonal antibody to GroEL and with human sera from patients with typhoid fever and normal healthy blood donors. Three immunogenic epitopes corresponding to peptides EGQDRGYSY, YSYNKETGE and GKGTEEKEK were identified upon screening with the human sera. In addition, screening of the peptides with a monoclonal antibody to GroEL detected binding to a third peptide, KGGKGTEEK, which contains a common overlapping sequence to peptide GKGTEEKEK. Identification and definition of these epitopes will be important in delineating the biological and immunological functions of this protein and in designing better diagnostic tests and vaccines.
Metalloporphyrins (and porphyrins) are well known as pigments of life in nature, since representatives of this group include chlorophylls (Mg-porphyrins) and heme (Fe-porphyrins). Hence, the construction of chemistry based on these substances can be based on the imitation of biological systems. Inspired by nature, in this article we present the preparation of five different porphyrin, meso-tetraphenylporphyrin (TPP), meso-tetra(p-anisyl)porphyrin (TpAP), tetrasodium meso-tetra(p-sulfonatophenyl)porphyrin (TSTpSPP), meso-tetra(m-hydroxyphenyl)porphyrin (TmHPP), and meso-tetra(m-carboxyphenyl)porphyrin (TmCPP) as well as their N-pincer Pd(II)-complexes such as Pd(II)-meso-tetraphenylporphyrin (PdTPP), Pd(II)-meso-tetra(p-anisyl)porphyrin (PdTpAP), Pd(II)-tetrasodium meso-tetra(p-sulfonatophenyl)porphyrin (PdTSTpSPP), Pd(II)-meso-tetra(m-hydroxyphenyl)porphyrin (PdTmHPP), and Pd(II)-meso-tetra(m-carboxyphenyl)porphyrin (PdTmCPP). These porphyrin N-pincer Pd(II)-complexes were studied and found to be effective in the base-free self-coupling reactions of potassium aryltrifluoroborates (PATFBs) in water at ambient conditions. The catalysts and the products (symmetrical biaryls) were characterized using their spectral data. The high yields of the biaryls, the bio-mimicking conditions, good substrate feasibility, evading the use of base, easy preparation and handling of catalysts, and the application of aqueous media, all make this protocol very attractive from a sustainability and cost-effective standpoint.
Random 15-mer peptides displayed on filamentous phages were screened in binding studies using a Chlamydia pneumoniae-specific monoclonal antibody (RR-402) and affinity-purified, polyclonal sera from patients seropositive for C. pneumoniae infections by the microimmunofluorescence (MIF) test. One 15-mer epitope, epitope Cpnl5A (LASLCNPKPSDAPVT) was identified in both the monoclonal and polyclonal screenings, and showed higher ELISA reactivity with C. pneumoniae MIF-positive sera compared to patients with other chlamydial infections, non-chlamydial respiratory infections and normal healthy sera (MIF-negative). Interestingly, epitope Cpnl5A also showed significant (52%) amino acid sequence homology to the 56 kDa type-specific antigen of Rickettsia tsutsugamushi, a protein implicated in the virulence of this organism.