Objective To investigate the possibility of commitment differentiation of embryonic stem cells induced by the medium of cultured retinal neurons of SD rats. Methods The medium from cultured retinal neurons of SD rats were collected, sterilized and mixed with DMEM medium according to 2∶3 proportion, ES cells were cultured with these mixed medium and were observed under the phase contrast microscope daily, the induced cells were identified by NF immunohistochemistry methods. Results The ES cells cultured with these mixed medium can differentiate into neuron like structure, and the induced cells were positive in NF immunofluorescence staining. Conclusion The medium from cultured retinal neurons of SD rats can induce ES cells commitment differentiation into neuron like structure.

The transcription factor p73 belongs to the p53 family of tumor suppressors,and can be transcribed into different isoforms with either pro-or anti-apoptotic(TAp73 and △Np73)functions.However,the tumor suppressor activity of TAp73 is inhibited through complex formation with inhibitory proteins(e.g.△Np73,mutant p53,MDM2 and iASPP).Therefore,it is a kind of tumor therapy strategy to reactivate TAp73 through targeting these inhibitors directly or release TAp73 from the complex by targeting their interaction.This review discusses the possible strategies of targeting p73 for its reactivation and the acting mechanism of related compounds.

OBJECTIVE: To observe the inhibiting effect of Interferon-alpha 1b(IFNa-1b) on proliferation of human tenon capsule fibroblasts. METHODS: Human tenon capsule fibroblasts were cultured in vitro and MTT method was used to detect the inhibiting effect of IFNa-1b on human tenon capsule fibroblasts. RESULTS: There was significant difference in OD values between 10~6IU/ml group(0. 1 109?0. 0 585) and control group(0.2535?0. 0502), the inhibition rate in IFN group was 56.25%. CONCLUSION: IFNa-1b has significant effect on inhibiting proliferation of human tenon capsule fibroblasts.

Objective To investigate the role of the ERG11 gene in the drug resistance of Trichosporon asahii (T.asahii), and to explore the relationship between the gene expression and drug concentrations. Methods Stable fluconazole-resistant strains of T.asahii were induced in vitro following exposure to a series of concentrations of fluconazole. Fluconazole-sensitive and-resistant strains of T.asahii were separately cultured in the medium containing fluconazole at concentrations of 0, 0.25, 0.5, 1, 2, 4, 8, 16, 32 and 64 μg/ml. Real-time quantitative PCR was performed to determine the mRNA expression of ERG11 gene. Results In fluconazole-free medium, the fluconazole-resistant strain of T.asahii showed significantly increased mRNA expression of the ERG11 gene compared with the fluconazole-sensitive strain (7.542 ± 5.311 vs. 1.014 ± 0.012, t=3.002, P=0.03). Additionally, the mRNA expression of ERG11 gene was also significantly higher in the fluconazole-resistant strains than the fluconazole-sensitive strains in the culture medium containing fluconazole at different concentrations of 0.25 (9.183 ± 3.226 vs. 3.281 ± 2.068), 0.5(13.657 ± 5.428 vs. 3.459 ± 1.923), 1(15.292 ± 7.007 vs. 3.242 ± 2.530), 2(13.720 ± 8.550 vs. 3.651 ± 0.728), 4(13.949 ± 2.960 vs. 3.969 ± 1.924)and 8(13.123 ± 6.429 vs. 3.824 ± 1.875)μg/ml(all P<0.05). However, no significant correlation was observed between the mRNA expression of ERG11 gene and fluconazole concentrations(fluconazole-resistant strains: rs = 0.229, P = 0.096; fluconazole-sensitive strains:rs=0.166, P=0.357). Conclusion Overexpression of ERG11 gene is associated with fluconazole resistance in T.asahii, but there is no correlation between the mRNA expression of ERG11 gene and fluconazole concentrations.

OBJECTIVE To identify if Trichosporon asahii exist cph1 gene homolog of Candida albicans,and analyze its nucleotide sequence.METHODS Nuclear DNA was extracted from the cells of T.asahii by using a simplified protocol,designed 29 pairs of primers according to the cph1 gene sequence of C.albicans and amplify by PCR.The PCR products were cloned and sequenced using the ABI377 nucleotide sequenator,and BLAST analysis.RESULTS An 827 bp gene was amplified successfully,which was homolog with the cph1 gene of C.albicans and their identity was 97.3%.CONCLUSIONS This trial determines the clone cph1 gene in T.asahii for the first time,which makes bases for the role of cph1 gene in the hypha formation.

Objective To observe morphological characteristics and activity distribution of T. asahii biofilm. Methods The morphological characteristics of T. asahii biofilm were observed under an inverted microscope and scanning electron microscope, and activity was measured and quantitatively analyzed by 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazo-lium hydroxide (XTT) assay and viable count, respectively. Spatial distribution of dead/vital cells, activity and thickness of biofilm at different layers were assessed under a confocal laser scanning microscope (CLSM) following double staining with FDA/PI. Results T. asahii formed a biofilm in vitro on the surface of polystyrene materials. Under a scanning microscope, the biofilm displayed a complex three-dimensional structure which composed of spores, pseudohy-pha and true hypha. As time prolonged, the activity and quantity of biofilm increased. The results of XTT assay were correlated with those of viable count (r = 0.94, P < 0.01). The activity was of no obvious difference between different layers of the biofilm. The thickness of biofilm varied from 14.3 μm to 31 μm. Conclusions The structure of T. asahii biofilm in vitro is more complex than that of planktonic T. asahii. The activity is of no significant difference between different layers of T. asahii biofilm.

Objective To determine the effect of interferon-gamma (IFN-γ) on the phagocytosis and killing activity of a murine macrophage cell line RAW264.7 against T.asahii,and to estimate the possibility of treating T.asahii infection with IFN-γγ.Methods T.asahii was cultured with or without the presence of different concentrations (10,100,1000 U/ml) of IFN-γfor 18 hours followed by the incubation with RAW264.7 cells for different durations.After additional culture for 45 minutes,the number of T.asahii cells phagocytosed by RAW264.7 cells was counted under an inverted microscope,and the rate of phagocytosis was calculated.The number of colony forming units of T.asahii per milliliter (cfu/ml) was counted after 4-hour additional culture and the growth inhibition rate was determined.Data were processed by the SPSS 16.0 software,and comparisons of parameters between these groups were done by Bonferroni method and analysis of variance after homogeneity test of variance.Results The number of phagocytosed T.asahiicells was 25.12 ± 1.81,35.88 ± 3.56,52.12 ± 3.23,with the phagocytosis rate being 25.12％,35.88％ and 52.12％,respectively in RAW264.7 cells incubated with IFN-γ of 10,100,1000 U/ml,significantly different from that in untreated RAW264.7 cells (13.62 ± 2.39,13.62％,all P ＜ 0.01).The colony forming units of T.asahii per ml after incubation with untreated RAW264.7 cells differed significantly from those after incubation with IFN-γ (10,100,1000 U/ml)-treated RAW264.7 cells ((68.12 ± 3.39) × 500 vs.(58.62 ± 4.89) × 500,(45.50 ± 3.02) × 500 and (34.62 ± 4.24) × 500,all P＜0.01),with the growth inhibition rate being 25.21％,41.95％ and 55.83％ respectively for RAW264.7 cells incubated with IFN-γ of 10,100,1000 U/ml.Statistical differences were also observed in the killing activity between RAW264.7 cells incubated with different concentrations of IFN-γ (all P ＜ 0.01).Conclusion IFN-γ (10-1000 U/ml) may enhance the phagocytosis and killing activity of RAW264.7 cells against T.asahii in a concentration-dependent manner.

Objective To induce fluconazole resistance in T.asahii by culture in medium containing increasing concentrations of fluconazole,and to evaluate the stability of the induced resistance.Methods Two T.asahii strains with a highest sensitivity to fluoconazole,including a clinical isolate CBS2479 (minumum inhibitory concentration (MIC) =0.25 μg/ml) and an environmental isolate CBS8904 (MIC =1.5 μg/ml),were selected from 11 T.asahii strains stored in the laboratory of the Department of Dermatology,General Hospital of Beijing Military Region.Both strains were respectively and serially subcultured in potato dextrose agar (PDA) medium containing growing concentrations of fluconazole (from 0.5 MIC to 256 μg/ml).E-test was performed to evaluate the susceptibility of T.asahii to fluconazole after each passage.To evaluate the stability of fluconazole resistance,the T.asahii isolates with induced resistance (MIC ＞ 256 μg/ml) were serially subcultured in drug-free PDA medium,and drug susceptibility assay was performed after each subculture.Results After serial culture in PDA medium containing fluconazole,high level of fluconazole resistance (MIC ＞ 256 μg/ml) developed in both of the fluconazole-susceptible T.asahii strains CBS2479 and CBS8904.The MIC value of fluconazole remained unchanged in the fluconazole-resistant strain CBS2479R,but gradually decreased to 64 μg/ml in the other resistant strain CBS8904R after 18-day culture in fluconazole-free PDA medium.Conclusions Fluconazole resistance can be induced in T.asahii strains from different origins by serial culture in medium containing growing concentrations of fluconazole,and the stability of the induced fluconazole resistance varies between strains of different origins.

Objective To investigate the effect and mechanism of miR-885-3p on the radiosensitivity of colorectal cancer cell HT-29. Methods The expression of miR-885-3p in HT-29 cells irradiated with different doses (0, 2, 4, 6, 8 Gy) of X-rays was detected by qPCR. The effect of miR-885-3p in modulating cell radiosensitivity was assessed in HT-29 cells with miR-885-3p overexpression. Bioinformatics prediction and dual luciferase reporter gene assay were employed to identify the direct target gene of miR-885-3p. Relationship between miR-885-3p and target gene tyrosine kinase 1 (AKT1) was investigated via regulation of miR-885-3p expression. The effect of AKT1 on radiosensitivity in HT-29 cells was evaluated through knockdown AKT1. The effect of AKT1 on miR-885-3p-induced radiosensitivity was detected by co-transferring miR-885-3p and AKT1 gene into HT-29 cells. Results miR-885-3p expression was up-regulated in radiation-induced HT-29 cells (F=46. 64, P<0. 05). Over-expression of miR-885-3p and knockdown of AKT1 enhanced cell radiosensitization by inhibiting survival and promoting apoptosis (t=12. 33, 12. 95, P <0. 05) with SER of 1. 602 and 1. 946, respectively. Inhibition of miR-885-3p promoted radioresistance by increasing cell survival and inhibiting apoptosis (t=11. 94, P<0. 05) with a SER of 0. 839. AKT1 is a target gene downstream of miR-885-3p, overexpression of AKT1 reversed the effect of miR-885-3p on cell radiosensitivity with a SER of 0. 680. Conclusions miR-885-3p can enhance the radiosensitivity of colorectal cancer HT-29 cells by directly targeting AKT1, which provides a target for improving the radiosensitivity of clinical colorectal cancer.