Narrow Results

We aimed to investigate the effects of Panax notoginseng saponins (PNS) on proliferation, differentiation and self-renewal of rat hippocampal neural stem cells (NSCs) in vitro. Rat hippocampal NSCs were isolated from post-natal day 1 (P1) rats and cultured in a serum-free medium. The neurospheres were identified by the expressions of nestin, class III β-tublin (Tuj-1) and glial fibrillary acid protein (GFAP). The cells were given PNS and subjected to oxygen glucose deprivation (OGD) as an in vitro model of brain ischemia reperfusion. The proliferation of NSCs was determined by MTT colorimetry, nestin/BrdU immunofluorescent double-labeling and RT-PCR. Differentiation of NSCs was assessed by immunofluorescent double-labeling of nestin/BrdU, nestin/vimentin, and nestin/Tuj-1. The primary cells and the first two passages of cells formed certain amount of neurospheres, the cells derived from a single cell clone also formed neurospheres. Nestin, BrdU, GFAP and Tuj-1-positive cells appeared in those neurospheres. Compared to the control group, PNS significantly promoted NSC proliferation and the expression of nestin/BrdU, and also enhanced Tuj-1, vimentin, and nestin mRNA expressions in hippocampal NSCs. PNS significantly increased area density, optical density and numbers of nestin/BrdU, nestin/vimentin, and nestin/Tuj-1 positive cells following OGD. These results indicate that PNS can promote proliferation and differentiation of hippocampus NCSs in vitro after OGD, suggesting its potential benefits on neurogenesis and neuroregeneration in brain ischemic injury.

This paper describes the synthesis of ZnO nanoparticles using air microplasma jets as the main reaction medium. Various techniques, including X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and UV—Vis spectroscopy, were employed to confirm the characterization of the artificially synthesized ZnO nanoparticles. The absence of additional peaks associated with secondary phases of ZnO, as revealed by the XRD analysis, indicates the exceptional purity of these nanoparticles. Through the use of SEM, we examined the surface morphology and observed a substantial rate of agglomeration. The energy band gaps of ZnO nanoparticles were determined to be 3.3 electron volts (eV). The cytotoxic effects of zinc oxide nanoparticles were assessed using the methyl thiazolyl tetrazolium (MTT) assay on breast cancer cells exposed to various doses of the nanoparticles. The Acridine-Orange/Ethidium-bromide (AO/EB) dual stain was employed to assess apoptotic cells. The data indicate that ZnO NPs can induce apoptosis, suggesting their potential as an anticancer treatment in breast cancer cell lines. The presented findings indicate that nanoscale zinc oxide particles (ZnO NPs) possess significant potential for future utilization in many biological applications. An example of such an application could be the prospective substitution for chemotherapy in the management of various forms of cancer diseases.

The NKX2.1 gene is considered as a proto-onco gene to promote the development of early lung adenocarcinoma. In this study, three kinds of specific siRNAs aiming to NKX2.1 gene were designed to down-regulate the expression of NKX2.1 gene, and constructed into rAAV vectors, respectively. NCI-H1975 cells were infected with the rAAV virus. RT-PCR results showed that all the three siRNAs decreased the expression of NKX2.1 mRNA. WB results show that the expression of NKX2.1 protein was decreased too. It is concluded that the siRNA constructed in rAAV could significantly down-regulate the expression of NKX2.1 gene. Meanwhile, it is proven that the rAAV-NKX2.1-siRNA could inhibit the proliferation and induce apoptosis occurrence in NCI-H1975 cells. In this study, we have expected that the rAAV-NKX2.1-siRNA could be developed into a potential genetic engineering therapeutic virus to suppress the lung AC development and metastasis. The current experiment thus makes a foundation for further research on in vivo gene therapy.

To observe the effect of Polysaccharides from Platycodonis Radix (PRPS) on the rat airway smooth muscle cells (ASMCs) proliferation in vitro. Methods: ASMCs were obtained from adult SD rats by trypsin-collagenase digestion method. In vivo experiment, the cells proliferating model of rat ASMCs were established by ET-1 and the intervention of PRPS. ASMCs were treated with PRPS at different concentrations and the growth of the cells was analyzed by MTT assay. The expression of PCNA in cells was detected by immunocytochemical method. Results: At the end of the experiment, the growth curve of high dosage group of PRPS was significantly lower than that in the model group (0.1521±0.0053). The expression of PCNA in this group was also lower than the model group and slightly higher in the dexamethasone treated group. Conclusion: PRPS can inhibit the proliferation of ASMCs induced by endothelin-1 in vitro, the mechanism has correlation with down- regulation of the expression and PCNA.

Four different assays, monitoring different aspects of cellular activity were used to assess the in vitro biocompatibility of three experimental zirconias (ZrO₂-A, ZrO₂-B and ZrO₂-C) with minor chemical modifications. The assays used were Neutral red uptake, MTT, alamarBlue and a live/dead cell stain. No cytotoxic effect was detected in the extracts from the three test zirconia samples using Neutral red uptake and MTT assays. However, a variation in response was observed in cells cultured directly on the surface of three test zirconias using the alamarBlue assay. The three test zirconia substrates showed no toxic effect after 1 and 2 days in culture. After 5 days in direct contact with the experimental zirconias, a significant decrease in cell activity was observed on sample ZrO₂-B, which was confirmed by fluorescence microscopy, showing a layer of dead cells (stained by thidium homodimer-1) on the sample surface. The findings from this study indicated that great care is required when selecting assays to assess the biocompatibility of modified materials with regard to the type and sensitivity of the assay and culture conditions.