[Abstract] Objective: To prepare GNS (gold nanostars) loading photosensitizer chlorin e6 (Ce6) and to investigate its photodynamic effects on lung cancerA549 cells. Methods: GNS was firstly modified by SH-PEG-NH2 and then mixed with Ce6 and shaken overnight to prepare GNS-PEG@Ce6, which had photodynamic therapy effects. The characterization, morphology and encapsulation rate were detected. The difference between the phagocytosis of Ce6 and GNS-PEG@Ce6 by A549 cells were observed with a Leical TCS SP8 confocal laser scanning microscope. MTT assay was used to examine the inhibitory effect of GNS-PEG@Ce6 on the proliferation of A549 cells while FCM was used to detect the effect of probe GNS-PEG@Ce6 on the apoptosis ofA549 cells. Results: The particle size of the GNS-PEG@Ce6 was about 100 nm. The prepared GNS-PEG@Ce6 nanoparticles exhibited good dispersion and stability and the encapsulation rate of Ce6 was about 50%. GNS-PEG@Ce6 entered the cells by endocytosis and mainly distributed in the cytoplasm; compared with Ce6, GNS-PEG@Ce6 could enter the cells more effectively. The proliferation-suppression effect of GNS-PEG@Ce6 on A549 cells was significantly stronger than that of Ce6 (P<0.05). The results of flow cytometry showed that the probe exhibited strong apoptotic effect on A549 cells. Conclusion: GNS, as the drug carrier, could effectively increase the Ce6 uptake efficacy in A549 cells, thus further enhancing the killing effects of Ce6 on lung cancerA549 cells.

BACKGROUND:Fluorescent magnetic nanoparticles with the properties of quantum dots and magnetic particles have good biocompatibility, and can label cels effectively through endocytosis. OBJECTIVE:To validate the feasibility of fluorescent magnetic nanoparticles in labeling human adipose-derived mesenchymal stem cels. METHODS:Healthy human adipose tissue was extracted and adipose-derived mesenchymal stem cels were isolatedin vitro by type I colagenase digestion. Passage 6 cels were incubated with the fluorescent magnetic nanoparticles overnight. Prussian blue staining and laser scanning confocal microscope were used to observe labeled adipose-derived mesenchymal stem celsin vitro after co-culturing with fluorescent magnetic nanoparticles. The tracing effect of labeled adipose-derived mesenchymal stem cels in vivo was detected by fluorescence imaging system. RESULTS AND CONCLUSION:Prussian blue staining showed that the fluorescent magnetic nanoparticles dispersed in the cytoplasm of adipose-derived mesenchymal stem cels in the form of blue particles. Under the laser scanning confocal microscope, the nuclei of adipose-derived mesenchymal stem cels were dyed blue by Hoechest33258, and the cytoplasm was dyed green. The fluorescence imaging results showed that labeled human adipose-derived mesenchymal stem cels had good imaging results. Therefore, as an efficient tracer, the fluorescent magnetic nanoparticles can label human adipose-derived stem cels in vitro and provide a new method for transplantation and transformation of adipose-derived mesenchymal stem cels.

We proposed a new algorithm for automatic identification of fluorescent signal. Based on the features of chromatographic chips, mathematic morphology in RGB color space was used to filter and enhance the images, pyramid connection was used to segment the areas of fluorescent signal, and then the method of Gaussian Mixture Model was used to detect the fluorescent signal. Finally we calculated the average fluorescent intensity in obtained fluorescent areas. Our results show that the algorithm has a good efficacy to segment the fluorescent areas, can detect the fluorescent signal quickly and accurately, and finally realize the quantitative detection of fluorescent signal in chromatographic chip.
Algorithms ; Chromatography ; Fluorescent Antibody Technique ; methods ; Image Processing, Computer-Assisted

RNA interference(RNAi)is a process by which introduced small interfering RNA(siRNA)can cause the specific degradation of mRNA with identical sequences. The human herpes simplex virus type 1(HSV-1)RR is composed of two distinct homodimeric subunits encoded by UL39 and UL40, respectively. In this study, we applied siRNAs targeting the UL39 and UL40 genes of HSV-1. We showed that synthetic siRNA silenced effectively and specifically UL39 and UL40 mRNA expression and inhibited HSV-1 replication. Our work offers new possibilities for RNAi as a genetic tool for inhibition of HSV-1 replication.

Objective To research whether the inhibitory oligonucleotides could improve the immune status of the BXSB mice. The purpose was to provide a valuable direction for treating systemic lupus erythematosus. Methods 3-month-old BXSB lupus mice were divided into three groups (including inhibitory oligonucleotides group, saline group and blank control group). The 24 hours urine proteins were determined before treatment. After treatment,the urine protein, anti-dsDNA, peripheral blood lymphocytes apoptosis and immune complex in renal glomeruli were measured. Results Before treatment,the urine proteins had no statistical differences among the three groups ( P > 0.05 ).After treatment,the urine protein, anti-dsDNA levels in inhibitory oligonucleotides group were significantly lower than that of control group(P < 0.01 ). Apoptosis of peripheral blood lymphocytes in inhibitory oligonucleotides group was significantly higher than that of control group( P < 0.05 ) ,immune complex in renal glomeruli in inhibitory oligonucleotides group was significantly lower than that of the other groups ( P < 0.05 ). Compared with saline group, inhibitory oligonucleotides had prolonged life period of BXSB mice ( P < 0.01 ). Conclusion The inhibitory oligonucleotides could improve immune status of BXSB, and could put off the disease progression.

Herpes simplex virus type 1 (HSV-1) is a commonly occurring human pathogen worldwide. There is an urgent need to discover and develop new alternative agents for the management of HSV-1 infection. Tripterygium hypoglaucum (level) Hutch (Celastraceae) is a traditional Chinese medicine plant with many pharmacological activities such as anti-inflammation, anti-tumor and antifertility. The usual medicinal part is the roots which contain about a 1% yield of alkaloids. A crude total alkaloids extract was prepared from the roots of T. hypoglaucum amd its antiviral activity against HSV-1 in Vero cells was evaluated by cytopathic effect (CPE) assay, plaque reduction assay and by RT-PCR analysis. The alkaloids extract presented low cytotoxicity (CC_(50) = 46.6 μg/mL) and potent CPE inhibition activity, the 50% inhibitory concentration (IC_(50)) was 6.5 μg/mL, noticeably lower than that of Acyclovir (15.4 μg /mL). Plaque formation was significantly reduced by the alkaloids extract at concentrations of 6.25 μg/mL to 12.5 μg/mL, the plaque reduction ratio reached 55% to 75% which was 35% higher than that of Acyclovir at the same concentration. RT-PCR analysis showed that, the transcription of two important delayed early genes UL30 and UL39, and a late gene US6 of HSV-1 genome all were suppressed by the alkaloids extract, the expression inhibiting efficacy compared to the control was 74.6% (UL30), 70.9% (UL39) and 62.6% (US6) respectively at the working concentration of 12.5μg/mL. The above results suggest a potent anti-HSV-1 activity of the alkaloids extract in vitro.

Objective: To construct the expression plasmid of a novel gene human NBEAL1 (neurobeachin like 1), and to study its relationship with the pathological grades of glioma. Methods: Total RNA of human glioma cell line U251 was extracted. NBEAL1 expression plasmid pGEX-KG/NBEAL1 was constructed and transferred into E. coli BL21. Recombinant NBEAL1 protein was induced by IPTG and further purified by GST affinity chromatographic column. The purity of recombinant NBEAL1 protein was examined by Western blotting analysis. A NBEAL1 protein specific monoclonal antibody was prepared and was used to study the relationship of NBEAL1 expression with pathological grades of glioma. Results: The NBEAL1 gene fragment was successfully cloned into pGEX-KG expression plasmid and verified by DNA sequencing. The recombinant NBEAL1 protein was expressed in inclusion bodies, with a yield of more than 30% of total bacterial proteins; the purity of purified NBEAL1 protein was above 95%. Western blotting analysis confirmed that the purified protein containing GST tag and NBEAL protein. NBEAL1 protein was lowly expressed in normal brain tissues and highly expressed in low grade glioma tissues; and the expression of NBEAL1 decreased with the increase of glioma malignancy. Conclusion: The NBEAL1 protein has been successfully cloned, expressed and purified. NBEAL1 protein expression in glioma tissues is negatively associated with the pathological grades of glioma.

Objective: To prepare a nanoprobe, anti-human melanoma ganglioside single chain variable fragment (GD/ScFvMEL) antibody conjugated with CdTe quantum dot, and to observe its ability to specifically bind human malignant melanoma cells. Methods: The GD/ScFvMEL gene was cloned into pET32a (+), and the plasmid was then transformed into E. coli BL21 (DE3) for GD/ScFvMEL protein antibody expression. The expressed GD/ScFvMEL antibody was purified by denaturing method and further refolded by modified dialysis method. The purified GD/ScFvMEL antibody was analyzed by SDS-PAGE. The GD/ScFvMEL-QDs nanoprobe was prepared by conjugating GD/ScFvMEL antibody with CdTe quantum dot, and its specificity was observed by incubating with MGC-803 cells and melanoma A375 cells. Results: The recombinant pET32a-GD/ScFvMEL was constructed and confirmed by PCR, restriction endonuclease analysis and DNA sequencing. The proportion of expressed GD/ScFvMEL antibody in total bacteria proteins was about 40% as detected by SDS-PAGE. The purified- and refolded-GD/ScFvMEL antibody was effectively conjugated with CdTe quantum dot, and the resulting GD/ScFvMEL-QDs nanoprobe was successfully prepared. The GD/ScFvMEL-QDs nanoprobe could specifically bind melanoma A375 cells, but could not bind stomach cancer MGC-803 cells. Conclusion: We have successfully prepared an anti-human melanoma ganglioside single-chain antibody-CdTe quantum dot nanoprobe, which can specifically bind melanoma cells.

BACKGROUND: In recent years, nano-carriers have been regarded as the most promising technologies for breakthrough the bottleneck of gene transfer. Polyamidoamine dendrimer (PAMAM) is a kind of new nanometer material. PAMAM can transfer target gene to the cell with high efficiency and lower toxic both in vivo and in vitro.OBJECTIVE: To evaluate the antitumour effects of survivin antisense oligonucleotide (Survivin-asODN) carried by PAMAM on colorectal cancer transplanted subcutaneously in nude mice.DESIGN, TIME AND SETTING: An in vivo experiment regarding tumor gene therapy was performed from February to August in 2008 at the Laboratory of Bionanometer Engineering, Research Institute of Micro/nanometer Science & Technology of Shanghai Jiao Tong University and Central Laboratory of Zhujiang Hospital of Southern Medical University.MATERIALS: Human colorectal cancer cells SW620 were from Shanghai Cell Institute of Chinese Academy of Sciences.PAMAM dendrimer was offered by the Bionanometer Engineering Laboratory, Research Institute of Micro/nanometer Science & Technology, Shanghai Jiao Tong University. Lipofectamine ~(TM)2000 was purchased from Invitrogen, USA. Survivin-asODN was synthesized by Shanghai Bioengineering Company.METHODS: The PAMAM and cation liposome were respectively mixed with Survivin-asODN to generate the transfection complex carrying antisense gene. The shape of the complex was observed by transmission electron microscope, the particle size was determined by laser particle size analysator and the zeta potential was measured by an analytical tool. The encapsulating efficiency and release progress in vitro were determined by ultraviolet spectrophotometer in centrifuging method. Human colorectal cancer cells SW620 at logarithmic phase were inoculated into the abdominal region of 18 Blab/C nude mice subcutaneously to produce transplanted tumor models in colorectal cancer nude mice, which were randomly divided into 3 groups: liposome, PAMAM and blank control groups. They were injected respectively with Hposome-survivin-asODN complex,PAMAM-survivin-as ODN transfection complex and seroculture liquid. The volumes of tumor were surveyed in the 2 groups.Western blotting method was used to determine the survivin gene expression in the transplanted tumor tissue.MAIN OUTCOME MEASURES: Particle size, zeta potential, gene loading level, encapsulation efficiency, release rate of cationic liposome-survivin-asODN complex and PAMAM-survivin-asODN complex, as well as survivin expression rate and apoptosis rate after transfection, inhibition rate of the transplanted tumor growth, Survivin protein expression and activity in the transplanted tumor cells.RESULTS: The particle size of PAMAM-survivin-asODN complex was smaller (P < 0.01), but the zeta potential was greater (P < 0.05), compared with liposome-survivin-asODN. There was no significant difference between PAMAM and liposome groups in terms of gene loading rate and transfection efficiency. DNA release lasted for 14 days for PAMAM, but only 5 days for liposome.After colorectal cancer cell transfection, survivin protein expression was lower, but apoptosis rate was higher, in the PAMAM-survivin-asODN complex than in the liposome-survivin-asODN complex (P < 0.05).CONCLUSION: PAMAM facilitates delivery of Survivin-asODN into transplanted colorectal cancer cells SW620. As a result,survivin protein expression was decreased, and apoptosis rate was increased in vivo which inhibited transplanied tumour growth.

Objective:To investigate the feasibility of targeted imaging and therapy of prostate cancer using nanocomposite probes composed of fluorescent magnetic nanoparticles(FMCNPs) and single chain Fv(ScFv) antibody specific for gama-seminoprotein.Methods:The nanocomposite probes(FMCNPs-ScFv) were prepared by conjugating fluorescent magnetic nanoparticles with singlegama-chain Fv antibody specific gama-seminoprotein,and were characterized by high resolution transmission electron microscopy,fluorescent spectrum and magnetic spectrum.Nanocomposite probes were incubated with prostate cancer LNCaP cells,and the targeting results of nanocomposite probes were observed by fluorescent microscopy.The cytotoxicity effect of the nanocomposite probes was measured by MTT.Nude mice models of prostate cancer were established and identified by immunohistochemistry method.The nanocomposite probes were injected into nude mice via tail vein.The distribution of nanocomposite probes in the nude mice was observed by Micro-animal imaging system,targeted imaging of the prostate cancer was observed by MR instrument.The nude mice with prostate cancer were irradiated with 100 W magnetic field for 30 min,and the changes of tumor sizes were observed.Results:The FMCNPs-ScFv nanocomposite probes were successfully prepared.Nanocomposite probes entered into the cytoplasm of cancer cells and exhibited low cytotoxicity effect.Nude mice model with prostate cancer were successfully fabricated;the nanocomposite probes distributed quickly in the main organs of mice,and gradually concentrated on the tumor tissues within 24 h.MR images showed that the tumor images were gradually enhanced from 6 h to 24 h after injection of the nanocomposite probe.Four days after magnetic irradiation,the tumors in the nude mice grew slower compared with the control nude mice(P