DNA methylation regulates expression of VEGF-C, and S-adenosylmethionine is effective for VEGF-C methylation and for inhibiting cancer growth

DNA hypomethylation may activate oncogene transcription, thus promoting carcinogenesis and tumor development. S-adenosylmethionine (SAM) is a methyl donor in numerous methylation reactions and acts as an inhibitor of intracellular demethylase activity, which results in hypermethylation of DNA. The main objectives of this study were to determine whether DNA hypomethylation correlated with vascular endothelial growth factor-C (VEGF-C) expression, and the effect of SAM on VEGF-C methylation and gastric cancer growth inhibition. VEGF-C expression was assayed by Western blotting and RT-qPCR in gastric cancer cells, and by immunohistochemistry in tumor xenografts. VEGF-C methylation was assayed by bisulfite DNA sequencing. The effect of SAM on cell apoptosis was assayed by flow cytometry analyses and its effect on cancer growth was assessed in nude mice. The VEGF-C promoters of MGC-803, BGC-823, and SGC-7901 gastric cancer cells, which normally express VEGF-C, were nearly unmethylated. After SAM treatment, the VEGF-C promoters in these cells were highly methylated and VEGF-C expression was downregulated. SAM also significantly inhibited tumor growth in vitro and in vivo. DNA methylation regulates expression of VEGF-C. SAM can effectively induce VEGF-C methylation, reduce the expression of VEGF-C, and inhibit tumor growth. SAM has potential as a drug therapy to silence oncogenes and block the progression of gastric cancer.

Manifestations oculaires au cours de la polyarthrite rhumatoide: a propos de 24 cas vues a Abidjan

Objectif : Determiner la prevalence et les principales manifestations oculaires au cours de la polyarthrite rhumatoide a Abidjan. Patients et Methode : Etude prospective descriptive de 24 polyarthrites rhumatoides repondant aux criteres de l'American College of Rheumatology; vues de Septembre 2003 a Aout 2004 au service de rhumatologie du CHU de Cocody. Les patients ont effectue un examen ophtalmologique comprenant: acuite visuelle; examen a la lampe a fente; fond d'oil; vision des couleurs et champ visuel. Resultats : Les manifestations oculaires etaient observees chez 9 des 24 patients soit une prevalence de 37;5 . Il s'agissait de 03 cas de baisse de l'acuite visuelle; 03 cas de cataracte; 02 cas de keratite et 01 cas d'uveite anterieure. Aucune anomalie au fond d'oil; a la vision des couleurs et du champ n'a ete mise en evidence. Ces manifestations ont ete decouvertes entre 5 et 10 ans (04 cas) et apres 10 ans (05 cas) d'evolution de la maladie. La duree de la polyarthrite rhumatoide influencait la survenue des manifestations oculaires (P=0;00). Conclusion : Les manifestations oculaires au cours de la polyarthrite rhumatoide sont peu frequentes dans notre pratique et etaient principalement des atteintes de l'acuite visuelle; des annexes et segment anterieur de l'oeil

Comparaison du mecanisme de l'action cardiotonique de la fraction 3 de mai- boa et de la digoxine sur le cour isole de rat

MAI-BAO est une boisson issue de la fermentation du the Camela sinensis sucre par le Champignon The-tresor. La fraction chromatographique no3 de MAI-BAO (MB-F3 ou F3) exerce un effet cardiotonique.But gomparaison du mecanisme d'activite cardiotonique de MB-F3 et de la Digoxine (Dx) chez le rat. Materiels et Methodes : MB-F3 obtenue par chromatographie sur gel sephadex G-50 et la digoxine sont utilisees pour perfuser le coeur isole de rat dont les contractions sont enregistrees avec le dispositif de Langendhorff. Le mecanisme biochimique de l'action cardiaque de MB-F3 et Dx est determine par dosage du phosphore selon la methode de Sumner. Resultats : MB-F3 exerce un effet cardiotonique inferieur a celui de Dx (P0;05) avec des Doses efficaces 50respectives de 1mg/ml et 10-6mg/ml. Par ailleurs; MB-F3 exerce une inhibition competitive inferieure a celle de Dx (P0;05) sur l'ATPase-Na+/K+.Conclusion : MB-F3 exerce une action digitalique-like inferieure a celle de Dx sur le coeur de rat

The effect of talisay (Terminalia catappa) extract on Staphylococcus aureus growth in vitro and Staphylococcus aureus-infected wounds in guinea pig (Cavia porcellus)

Seventeen Philippine plants were subjected to antimicrobial screening against Staphylococcus aureus and Escherichia coli using antimicrobial disc assay. The result showed that Terminalia catappa, locally known as "talisay", exhibited the highest antimicrobial activity against S. aureus and none against E. coli. The growth of Staphylococcus aureus inoculated in nutrient broth with different concentrations of the T. catappa extract was determined by measuring cell density at 0 hours and 24 hours of inoculation. The results showed that bacterial cell density decreased significantly after 24 hours of inoculation in the plant extract. Talisay was further tested for its wound healing properties on 2 groups (group 1: standard drug vs. negative control; group 2: herbal extract vs. negative control) of guinea pigs using the abrasion method. A swab of inoculum of S. aureus was applied for infecting the wound. Differences in degrees of wound healing determined by free radical scavenging activity, colony forming units (CFU) counting and histopathologic analysis were noted. Samples from wound abscesses remaining after 48 hours of application of extract were swabbed in petriplates containing 20 ml nutrient agar and were verified using the catalase test. The CFUs were counted 24 hours after incubation. Crude extract was further subjected to High Pressure Liquid Chromatography (HPLC) yielding a polar substance suspected to be of the aromatic tannin family. ANOVA revealed significant difference in the positive control and negative control results against the T. catappa extract treatment in the in vivo antimicrobial activity model. Among these setups, the wounds treated with the extract exhibited advanced healing as supported by significantly lower absorbance levels in the antioxidant assay, lower CFU count, and significantly higher grade in wound healing parameters for histopathologic analysis. The T. catappa extract under study showed significant inhibition of growth of S. aureus and effective healing of infected wounds