Research on natural products has been widely used as a strategy to discover new drugs with potential for applications in complementary medicines because they have fewer side effects than conventional drugs. The aim of the present study was to evaluate the in vitro cytotoxic effects of crude aqueous Catharanthus roseus extract on Jurkat cells and normal peripheral blood mononuclear cells (PBMCs). The aqueous extract was
standardised to vinblastine by high performance liquid chromatography (HPLC) and was used to determine cytotoxicity by the MTS [3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay. DNA fragmentation assay was employed to determine if cell death was due to apoptosis. The results showed that the aqueous extract induced cell death of Jurkat cells at 24, 48 and 72 hours posttreatment in a time- and dose-dependent manner. However, cells treated at 48 and 72 hours produced higher cytotoxic effects with half maximal inhibitory concentration (IC50)values of 2.55 µg/ml and 2.38 µg/ml, respectively. In contrast, the extract induced normal PBMC proliferation, especially after 24 hours treatment with 1000 µg/ml. This result indicates that the C. roseus crude aqueous extract showed differential effects of inhibiting the proliferation of the Jurkat cell line and promoting the growth of PBMCs. These data suggest that the extract may be applicable for modulating the normal and transformed immune cells in leukaemia patients.
One-dimensional nanostructure materials are very attractive because of their electronic and optical properties depending on their size. It is well known that properties of material can be tuned by reducing size to nanoscale because at the small sizes, that they behave differently with its bulk materials and the band gap will control by the size. The tunability of the band gap makes nanostructured materials useful for many applications. As one of the wide band gaps semiconductor compounds, zinc selenide (ZnSe) nanostructures (nanoparticles, nanowires, nanorods) have received much attention for the application in optoelectronic devices, such as blue laser diode, light emitting diodes, solar cells and IR optical windows. In this study, ZnSe nanostructures have been synthesized by reduction process of zinc selenate using hydrazine hydrate (N2H4.2H2O). The reductive agent of hydrazine hydrate was added to the starting materials of zinc selenate were heat treated at 500 o C for 1 hour under argon flow to form onedimensional nanostructures. The SEM and TEM images show the formation of nanocompositelike structures, which some small nanobars and nanopellets stick to the rod. The x-ray diffraction and elemental composition analysis confirm the formation of mixture zinc oxide and zinc selenide phases.
Titanium oxide (TiO2) nanotubes were successfully formed by anodization of pure titanium foil in a standard two-electrode bath consisting of ethylene glycol solution containing 5 wt% NH4F. The pH of the solution was ∼ 7 and the anodization voltage was 60 V. It was observed that such anodization condition results in ordered arrays of TiO2 nanotubes with smooth surface and a very high aspect ratio. It was observed that a minimum of 1 wt % water addition was required to form well ordered TiO2 nanotubes with length of approximately 18.5 μm. As-anodized sample, the self-organized TiO2 nanotubes have amorphous structure and annealing at 500oC of the nanotubes promote formation of anatase and rutile phase. Photocatalytic activity of well ordered TiO2 nanotubes with two different lengths was evaluated by measuring the degradation of methyl orange (MO). The elaboration of this observation is described in detail in this paper.
Anti-nuclear antibody (ANA) negative systemic lupus erythematosus (SLE) occurs in about 4-13% of SLE cases. A small group of ANA negative SLE patients with positive anti-Ro antibodies usually present with typical vasculitic skin lesions which can be associated with photosensitivity, renal disease, congenital heart block or neonatal lupus. We present a case of a persistently ANA negative patient who presented with joint pain, rashes, mouth ulcer and alopecia. Clinical diagnosis of systemic lupus erythematosus was made even though ANA was negative. She was started on steroids and went into remission. Later, she developed several episodes of convulsions associated with fever and prominent vasculitic lesions. The patient was also found to have microscopic hematuria, proteinuria, anemia and thrombocytopenia. Renal biopsy showed lupus nephritis class 1B. Due to the prominent skin lesions, we performed anti-extractable nuclear antigens (ENA) antibodies test and anti-Ro turned out to be positive. The final diagnosis was ANA negative SLE (Ro lupus) with cutaneous, renal, musculoskeletal, hematological and cerebral Involvement.