The xCELLigence real-time cell analysis (RTCA) system is an established electronic cell sensor array. This system uses microelectronic biosensor technology that is verified for real-time, label-free, dynamic and non-offensive monitoring of cellular features, including detection of viral cytopathic effect (CPE). Screening viral replication inhibitors based on presence of CPE has been applied for different viruses, including chikungunya virus (CHIKV). However, most CPE-based methods, including MTT and MTS assays, do not provide information on the initiation of CPE nor the changes in reaction rate of the virus propagation over time. Therefore, in this study we developed an RTCA method as an accurate and time-based screen for antiviral compounds against CHIKV.
A retrospective study was conducted at the Hospital Sultanah Aminah Johor Bahru to determine the outcome of trabeculectomy surgeries over a period of 4 years. One hundred and two eyes were followed up to a maximum of 63 months (mean 34.2 months). The 2-year survival rates for plain trabeculectomies, 5-Fluorouracil augmented trabeculectomies and Mitomycin-C augmented trabeculectomies were 52.9%, 27.3% and 60.5% respectively. The commonest complications noted were cataract formation (25%) and hyphaema (11%). Mitomycin-C induced complications were rarely seen. At last follow-up, 54% of eyes had intraocular pressures below 21 mmHg without medication, while 34% of eyes had intraocular pressures below 21 mmHg with medication. Vitreous at the trabeculectomy site was a statistically significant predictor of operative failure.
The chromosomal aberrations (CA) assay and micronucleus (MN) test were employed to investigate the effect in vitro of zerumbone (ZER) on human chromosomes. ZER is a sesquiterpene compound isolated from the rhizomes of wild ginger, Zingiber zerumbet Smith. The rhizomes of the plant are employed as a traditional medicine for some ailments and as condiments. ZER has been shown to have anti-cancer and apoptosis-inducing properties against various human tumour cells. It has also been shown to be active in vivo against a number of induced malignancies. Studies on ZER genotoxicity in cultured human peripheral blood lymphocytes (PBL) have not been reported so far. Therefore, the present study was undertaken to investigate the ability of ZER to induce chromosomal aberrations and micronuclei formation in human lymphocytes in vitro. Human blood samples were obtained from four healthy, non-smoking males aged 25-35years. Cultures were exposed to the drug for 48h at four final concentrations: 10, 20, 40 and 80 microM. Mitomycin C (MMC) was used as a positive control. The results of chromosomal aberrations assay showed that ZER was not clastogenic, when compared to untreated control, meanwhile MN test results showed a dose-dependent increase in MN formation. The overall clastogenic effect of ZER on human PBL was statistically not significant. In conclusion, ZER is a cytotoxic but not a clastogenic substance in human PBL.
The aim of this study was to determine the role of intracellular proteins in phagocytosis of opsonized Porphyromonas gingivalis by RAW264.7 cells, a murine macrophage-like cell line. This periodontopathogen was grown anaerobically and opsonized with an IgG2a murine monoclonal anti-P. gingivalis lipopolysaccharide antibody. RAW264.7 cells were preincubated with protein tyrosine kinase inhibitors (staurosporine and genistein), protein kinase C inhibitors (phorbol myristic acetate and bisindolylmaleimide), a serine/threonine phosphatase inhibitor (okadaic acid), a phosphatidylinositol 3-kinase inhibitor (worthmannin), phospholipase A2 inhibitors (bromophenacyl bromide and nordihydroguaiaretic acid), phospholipase C inhibitors (p-chloromercuriphenyl sulfonate and neomycin sulfate), an actin-filament depolymerizer (cytochalasin D), and a microtubule disrupting agent (colchicine). Inhibitor-treated macrophages were then incubated with the opsonized P. gingivalis and the phagocytosed cells determined microscopically. The results showed the percentage of the phagocytosed organisms decreased when the cells were preincubated with protein tyrosine kinase, protein kinase C, protein phosphatase and phosphatidylinositol 3-kinase inhibitors. Of interest, preincubation with phorbol myristic acetate for 30 min increased the ability of RAW264.7 cells to phagocytose the opsonized organisms. Phospholipase A2 and phospholipase C inhibitors only slightly reduced the number of phagocytosed organisms. The results indicated that opsonophagocytosis of P. gingivalis by RAW264.7 cells might be determined by the activation of protein tyrosine kinase, protein kinase C, protein phosphatases, and phosphatidylinositol 3-kinase inhibitor. Both phospholipase A2 and phospholipase C would appear to be involved to a lesser extent. The opsonophagocytosis of this periodontopathogen would also appear to be dependent upon actin and microtubule polymerization.