Test of the ability of HPV L1 conserved sequence polypeptide to antisera to degrade HPV6 infection / 中国免疫学杂志

Objective:To determine whether human papillomavirus(HPV L1)C-terminal conserved sequence antibodies with cross-reactive major capsid proteins of different types of HPV L1 have the ability to degrade HPV6 infection.Methods:Condyloma specimens were collected,HPV6 infection cases were identified from the collected samples,and virus was extracted.Polypeptide anti-sera were diluted in different proportions,and then co-cultured and neutralized with the resulting virus,then removed to contact mono-layer-cultured human immortalized keratinocytes and tested by HPV6 disease using PCR.Content of HPV6 DNA in human immortalized keratinocytes was exposed,and the presence of HPV6 L1 protein in this cells was tested by ELISA.Results:Human immortalized ke-ratinocytes infected with HPV6 virus neutralization at different dilution concentrations,the PCR products of their DNA extracts were electrophoresis and showed positive bands of HPV6 specificity zone at 280 bp of the gel,and the intensity of positive bands gradually decreased with increasing antiserum concentration.Protein extracted from human immortalized keratinocytes exposed to anti-serum neutralizing virus was tested by ELISA,and the amount of HPV L1 protein showed the same gradient trend as the above PCR test results,and the difference were statistically significant.Conclusion:It is preliminarily proved that HPV6 L1 conserved sequence polypeptide antisera can partially degrade the infection ability of the virus,and it has the value of studying more HPV neutralization types.

Protective Effects of Raspberry Crude Polysaccharides on UVB-Induced Photodamage in HaCaT Cells / 中国生物化学与分子生物学报

Polysaccharide is one of the functional components of the raspberry, which has various pharmacological effects such as anti-inflammatory, antioxidant, anti-fatigue, hypoglycemic and immunomodulatory. However, whether raspberry polysaccharides have protective effects on UV-induced photodamage to skin cells has not been reported. This study aims to investigate the protective effect of Raspberry Crude Polysaccharide on Ultraviolet B (UVB) -induced photodamage of human immortalized keratinocytes (H a C a T). The photodamage model of HaCaT cells was established by UVB irradiation. To evaluate the anti-UVB activity of R C P, the cell viability was determined by the CCK-8 method, and the Enzyme-linked immunosorbent assays (ELISA) and microplate method were used to measure the contents of matrix metalloproteinase, inflammatory and antioxidant factors in the photodamaged HaCaT cells. The antioxidant activity of RCP was detected by radical scavenging assays against D P P H radical (D P P H •) and ABTS radical (ABTS •

Effect of pterostilbene on the growth, apoptosis and autophagy of a human papillomavirus type 16-immortalized cervical epithelial cell line H8 / 中华皮肤科杂志

Objective:To investigate the effect of pterostilbene on the growth, apoptosis and autophagy of a human papillomavirus type 16 (HPV-16) -immortalized cervical epithelial cell line H8.Methods:H8 cells were treated with pterostilbene at different concentrations of 0 (control group) , 25, 50, 75, 100 μmol/L for 24 and 48 hours. Cell counting kit-8 (CCK8) assay was performed to evaluate the cellular proliferative activity, flow cytometry was conducted to detect apoptosis and cell cycle, monodansylcadaverine (MDC) staining and fluorescence microscopy were performed to detect autophagy, and Western blot analysis was conducted to determine the expression of the cell cycle-related protein cyclinD1, apoptosis-related proteins caspase-3 and caspase-9, autophagy-related proteins Beclin1, microtubule-associated protein 1 light chain 3 (LC3) -Ⅱ/Ⅰ, ATG5 and P62, as well as HPV oncoproteins E6 and E7. Statistical analysis was carried out by using one-way analysis of variance, repeated measures analysis of variance and least significant difference- t test. Results:After 48-hour treatment with pterostilbene at different concentrations of 0, 25, 50, 75, 100 μmol/L, the relative cellular proliferation rate significantly differed among the groups (100.00% ± 1.56%, 99.02% ± 4.97%, 93.59% ± 2.01%, 81.28% ± 4.90%, 69.17% ± 7.56%, respectively; F = 77.22, P < 0.05) , and gradually decreased along with the increase in the concentration of pterostilbene; compared with the control group, the pterostilbene groups all showed significantly decreased cellular proliferation rate (all P < 0.05) . After 24-hour treatment with pterostilbene, the proportions of H8 cells at G1, G2 and S phases significantly differed among the above groups ( F = 7 845.00, 51.14, 266.50, respectively, all P < 0.05) ; compared with the control group, the pterostilbene groups showed significantly increased proportions of H8 cells at G1 and G2 phases (all P < 0.05) , but significantly decreased proportions of H8 cells at S phase ( P < 0.05) . After 48-hour treatment with pterostilbene, the apoptosis rate was significantly higher in the 25-, 50-, 75- and 100-μmol/L pterostilbene groups (14.66% ± 0.22%, 13.50% ± 0.49%, 14.56% ± 0.19%, 15.30% ± 0.76%, respectively) than in the control group (11.58% ± 0.50%, all P < 0.05) . After 24-hour treatment with pterostilbene, MDC staining showed only a small number of H8 cells with bright dot-like fluorescence in the control group, but increased number of autophagosome-positive H8 cells with bright dot-like fluorescence in the pterostilbene groups. Western blot analysis revealed that there were significant differences in the protein expression of cyclin D1, caspase-3, caspase-9, Beclin1, LC3-Ⅱ/Ⅰ, ATG5, P62, E6 and E7 among the control and pterostilbene groups after 24- and 48-hour treatment with pterostilbene (all P < 0.05) . The treatment with pterostilbene could down-regulate the expression of cyclin D1, E6 and E7, and up-regulate the expression of caspase-3, caspase-9, Beclin1, LC3-Ⅱ/Ⅰ, ATG5 and P62, with significant differences between the control group and most pterostilbene groups in expression of the above proteins (all P < 0.05) . Conclusion:Pterostilbene can inhibit the proliferation of H8 cells, promote their apoptosis and autophagy, and down-regulate the expression of oncogenes E6 and E7.

Protective effect of nuclear factor E2-related factor 2 on oxidative injury in human immortalized epidermal cells / 解剖学报

Objective To investigate the protective effect of nuclear factor E2-related factor 2(Nrf2)on hydrogen peroxide (H

Bone morphogenetic proteins 2, 6, and 9 differentially regulate the osteogenic differentiation of immortalized preodontoblasts

Our study attempted to compare the efficacies of bone morphogenetic protein (BMP) 2, 6, and 9 in inducing osteogenic differentiation of preodontoblasts (PDBs). We immortalized PDBs by introducing a reversible SV40 T antigen-based immortalization system. Cell proliferation capability was examined by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. The effects of BMP2, 6, and 9 on the osteogenic differentiation of immortalized preodontoblasts (iPDBs) were measured by alkaline phosphatase (ALP) activity assays and alizarin red S staining. The expression of osteogenic markers was evaluated by semiquantitative real-time polymerase chain reaction analysis. To assess ectopic bone formation, rat-derived iPDBs were transfected in culture with adenoviral vectors designated Ad-BMP2, 6, and 9 and subcutaneously or intramuscularly injected into mice. Several BMPs retained endogenous expression in PDBs and regulated the mRNA expression of mineralized tissue-associated proteins. ALP activity and mineralized nodule formation were significantly increased in the Ad-BMP9-transfected group relative to the control group. In addition, the most significant hard tissue formation was in this group. The results indicated that BMP signaling was involved in the osteogenic differentiation of iPDBs. BMP9 could be an efficacious accelerant of the osteogenic differentiation of iPDBs.

Establishment of an immortalized mouse mammary epithelial cell fines / 中华内分泌外科杂志

Objective To provide experimental materials for exploring the function of breast cancer susceptibility gene 2(BRCA2) gene by establishing of an mouse immortalized mammary gland epithelial cell line as a cell model system.Methods In this study,the primary mouse mammary epithelial cells were isolated and purified by enzyme digestion and differential centrifugation.The resulting primary mouse mammary gland epithelial cells were transducted with lentivirus expressing human telomerase (hTERT) gene,and screened by hygromycin B.The surviving epithelial cells were further characterized by morphology observations and cytokeratin marker detection.Results Immortalized mouse mammary epithelial cells were obtained by infection of MMECs with lentivirus expressing human telomerase(hTERT) gene,screened by hygromycin B.Morphology observations and detection of the cytokeratin marker showed the immortalized MMECs had a typical morphology of luminal epithelial cells with strong expression of cytokeratin 14.Conclusion An immortalized mouse luminal epithelial cell line is successfully established with an uniform morphology,which provides a cell model system for the future exploration on BRCA2-related tumorigenesis.

Effect of tea polyphenois on the growth of human papilIomavirus 16 subgenes-immortalized human cervical epithelial cells / 中华皮肤科杂志

Objective To explore the effect of tea polyphenols on the growth of human papillomavirus 16 (HPV16) subgenes-immortalized human cervical epithelial cells (H8 cells).Methods Cultured H8 cells were divided into 5 groups to be treated with 0 (control group),6.25,12.5,25 and 50 mg/L tea polyphenols respectively for 24,36,and 48 hours,and then cell counting kit-8 (CCK8)assay was performed to detect cell proliferation.After 24 hours of incubation,flow cytometry was conducted to detect cell apoptosis and cell cycle,and fluorescence microscopy to observe the morphology of apoptotic cells.Results After incubation with tea polyphenols at different concentrations for 24,36 and 48 hours,the proliferation of H8 cells was inhibited,and 12.5 mg/L tea polyphenols could inhibit the relative growth rate of H8 cells in a time-dependent manner.Flow cytometry showed that there was a significant difference in cell apoptosis rate among the 6.25-,12.5-,25-,50-mg/L tea polyphenols groups and the control group (52.62％ ± 0.62％,52.22％ ± 0.72％,42.52％ ± 0.90％,45.96％ ± 2.11％,29.96％ ± 0.70％ respectively,F =272.0,P ＜ 0.05).Moreover,all the tea polyphenol groups showed significantly increased cell apoptosis rate compared with the control group (all P ＜ 0.05).Fluorescence microscopy showed karyopyknosis,nuclear fragmentation and other typical apoptotic morphological changes in H8 cells in tea polyphenols groups.There were significant differences in the percentage of cells in G1,G2 phase and cell proliferation index among the 5 groups (all P ＜ 0.05).Compared with the control group,the 6.25-,12.5-,25-mg/L tea polyphenols groups showed significantly increased percentage of cells in G1 phase (55.96％ ± 0.72％,54.12％ ± 3.20％,65.30％ ± 1.51％ respectively,all P ＜ 0.05),but significantly decreased percentage of cells in G2 phase (3.17 ± 1.82％,4.94 ± 1.46％,4.65 ± 4.26％ respectively,all P ＜ 0.05) and lower cell proliferation index(0.44 ± 0.01,0.46 ± 0.02,0.36 ± 0.01 respectively,all P ＜ 0.05).Conclusion Tea polyphenols can inhibit the proliferation of H8 cells,induce cell apoptosis,and block cell cycle progression.

BMP9 Regulates Osteogenic/Odontogenic Differentiation of Immortalized Stem Cells from the Apical Papilla via the ERK5 Pathway / 中国医科大学学报

Objective The aim of this study was to investigate the effects of the ERK5 pathway on bone morphogenetic protein?9(BMP9)?regu?lated osteogenic/odontogenic differentiation of immortalized stern cells from the apical papilla(iSCAP). Methods BMP9 was introduced into the iSCAP by using recombinant adenoviruses,and the P?ERK5 protein expression was measured via western blotting. Then,the osteogenic/odontoblas?tic changes were analyzed by alkaline phosphatase(ALP)staining and Alizarin red staining,and the expression of osteogenic/odontoblast?associat?ed genes,such as Runx2,OCN,OPN,and DMP1 was measured by RT?PCR. Results BMP9 could up?regulate the phosphorylation of ERK5 in iSCAP. After using BIX02189,which was an inhibitor of ERK5,the phosphorylation of ERK5;the activity of ALP;the expression of Runx2, OCN,OPN,and DMP1;and the calcium deposition were all significantly inhibited. Conclusion The ERK5 signaling pathway plays an important role in BMP9?regulated osteogenic/odontogenic differentiation of iSCAP.

Investigation of the cytotoxicity of thermoplastic denture base resins

PURPOSE: The purpose of this study was to investigate the in vitro cytotoxicity of thermoplastic denture base resins and to identify the possible adverse effects of these resins on oral keratinocytes in response to hot water/food intake. MATERIALS AND METHODS: Six dental thermoplastic resin materials were evaluated: three polyamide materials (Smile tone, ST; Valplast, VP; and Luciton FRS, LF), two acrylic materials (Acrytone, AT; and Acryshot, AS), and one polypropylene resin material (Unigum, UG). One heat-polymerized acrylic resin (Vertex RS, RS) was chosen for comparison. After obtaining extracts from specimens of the denture resin materials (Φ=10 mm and d=2 mm) under different extraction conditions (37℃ for 24 hours, 70℃ for 24 hours, and 121℃ for 1 hour), the extracts (50%) or serial dilutions (25%, 12.5%, and 6.25%) in distilled water were co-cultured for 24 hours with immortalized human oral keratinocytes (IHOKs) or mouse fibroblasts (L929s) for the cytotoxicity assay described in ISO 10993. RESULTS: Greater than 70% viability was detected under all test conditions. Significantly lower IHOK and L929 viability was detected in the 50% extract from the VP (70℃) and AT (121℃) samples (P < .05), but only L929 showed reduced viability in the 50% and 25% extract from LF (37℃) (P < .05). CONCLUSION: Extracts obtained from six materials under different extraction conditions (37℃, 70℃, and 121℃) did not exhibit severe cytotoxicity (less than 70% viability), although their potential risk to oral mucosa at high temperatures should not be ignored.

Optimization of Recombinant Human Platelet-Derived Growth Factor-BB Encapsulated in Poly (Lactic-co-Glycolic Acid) Microspheres for Applications in Wound Healing

Growth factors play multiple and critical roles in wound repair processes. Platelet-derived growth factor (PDGF) is a potent growth factor that is particularly important in the early inflammatory phase of wound healing. In order to extend the half-life of PDGF, polymeric encapsulation is used. In the current study, Poly (lactic-co-glycolic acid) (PLGA) microspheres containing recombinant human (rh) PDGF-BB were prepared to prolong the effectiveness of this growth factor. PLGA microspheres were optimized using a modified w/o/w-double-emulsion/solvent evaporation method by changing the processing conditions of stirring speed and emulsifier (polyvinyl alcohol) concentration. Microspheres prepared using the optimized method released rhPDGF-BB for up to three weeks. An in vitro migration assay showed a significant decrease in the wound area in cells treated with rhPDGF-BB microspheres compared to control cells. These findings demonstrate the potential of rhPDGF-BB encapsulated in microspheres to enhance wound healing.

CONSTRUCTION OF IMMORTALIZEDBONE MARROW MESENCHYMAL STEM CELLS / 现代医院

Objective To establish immortalized bone marrow mesenchymal stem cells (BMSCs) from SD rats in vitro for further research on the characteristics and clinical application of BMSCs.Methods By using L ipo-fectamine TM 2000 -mediated gene transfection, plasmid pCMVSV40T/PUR containing the simian virus 40 large T antigene gene (SV40Tag) was transfected into BMSCs.BMSCs were screened by puromycin and then cultured on an extended scale.Their cell morphology and growth conditions were observed.Growth curve of cells was graphed.The expression of SV40Tag in transfected cells was identified by enzyme digestion method for the detection of tumor forma-tion.Results The growth rate of the experimental group of BMSCs after the 7th generation was significantly higher than that of the control group.No tumorigenicity was found in BMSCs after the 7th generation.Conclusion In vitro, the immortalized BMSCs by pCMVSV40T/PUR can provide basis on a large scale for its application in clinic and sci-entific research.

Efeito dual de FGF2 e PMA em células HEK 293 transformadas por H-rasV12 / Dual effects of FGF2 and PMA on H-rasV12 transformed HEK293 cell line

Sabe-se há décadas que mutações nos genes ras estão presentes em cerca de 20% dos cânceres humanos, mas o desenvolvimento de terapias eficazes para o tratamento de câncer dependente dos oncogenes ras permanece um desafio científico importante. Nesse contexto, o nosso grupo publicou recentemente resultados interessantes mostrando que FGF2 exógeno ou PMA, contrariamente à expectativa geral, inibem a proliferação de células de camundongo malignas dependentes dos oncogenes H- ou K-Ras. Para dar continuidade a estes estudos o projeto desta tese foi planejado para investigar os mecanismos subjacentes a possíveis efeitos citotóxicos de FGF2 e PMA em células humanas transformadas por ras. Para esse fim, a linhagem humana imortalizada HEK 293 foi condicionalmente transformada pela expressão ectópica da construção quimérica de DNA ER:H-rasV12, que codifica a oncoproteína de fusão ER:H-RasV12, cuja atividade é induzível por 4-hidroxi-tamoxifen (4OHT). Essa abordagem nos permitiu verificar os efeitos de FGF2 e PMA em sublinhagens HEK/ER:HrasV12 fenotipicamente "normais" ou transformadas por níveis crescentes da oncoproteína H-RasV12. Os principais resultados mostraram que tanto FGF2 como PMA tem efeito dual promovendo ou inibindo a proliferação das células transformadas em função da concentração intracelular crescente de H-RasV12. Ensaios de crescimento de colônias em suspensão de agarose mostraram que: a) as células parentais HEK293 não desenvolveram colônias mesmo quando tratadas com FGF2 ou PMA, resultados que estão de acordo com seu fenótipo não tumoral; b) mas, as sublinhagens HEK/ER:HrasV12 deram origem a colônias mesmo quando tratadas com concentrações pequenas de 4OHT, que condicionaram níveis intracelulares baixos de ER:HRasV12; nestas condições experimentais, FGF2 foi um forte promotor do crescimento de colônias, condizente com sua reconhecida atividade promotora do crescimento de células tumorais em suspensão; ainda nestas condições, PMA não teve efeito significante sobre o crescimento de colônias; c) coerentemente, concentrações elevadas de 4-OHT levaram aos níveis intracelulares mais altos de ER:HRasV12 e, por conseguinte, a desenvolvimento máximo de colônias de células HEK/ER:HrasV12, no entanto, nestas condições, ambos FGF2 e PMA inibiram completamente o crescimento de colônias. Por outro lado, transformação de HEK293 com um vetor de expressão constitutiva de HrasV12 levou à seleção e isolamento das sublinhagens tumorais HEK/HrasV12, cujo fenótipo se caracterizou por: a) nenhum efeito de FGF2 sobre a sua proliferação e b) forte inibição de sua proliferação por PMA. A ação citotóxica de PMA exclusivamente observada em células HEK 293 transformadas por H-rasV12 se caracterizou por: a) total dependência de PKC, provavelmente mediada pela ativação proteolítica específica de PKC δ; b) envolvimento de níveis elevados e sustentados de ROS com disparo tardio de apoptose

It is known for nearly 20 years that mutated ras oncogenes are found in 20% of human malignancies, however efficacious therapies are not yet available for Ras-driven cancer. Along of these lines, our group recently published provocative results showing, against common belief, that FGF2 and PMA inhibited proliferation of Ras-dependent malignant mouse cells. Aiming to gain insight into this intriguing phenomenon, the present thesis project was planned to investigate the possible cytotoxicity of FGF2 and PMA in human Ras-driven malignant cells. To this end an immortalized non-tumorigenic human cell line (HEK293) was stably transformed with the DNA construction ER:H-rasV12, which encodes the fusion protein ER:H-RasV12, whose activity requires activation by 4-hidroxitamoxifen (4-OHT). This approach allowed us to evaluate FGF2 and PMA effects on HEK/ER:HrasV12 sublines under switching from "normal" to transformed phenotypes upon 4-OHT induction. Our main results have shown that both FGF2 and PMA displayed dual effects promoting or inhibiting proliferation of HEK/ER:HrasV12 cells in function of ER:HRasV12 intracellular levels. Clonogenic assays in agarose suspension have shown: a) parental HEK293 line did not develop colonies under FGF2 and PMA treatment or not, in agreement with its non-tumorigenic nature; b) however, HEK/ER:HrasV12 sublines developed colonies even under low 4-OHT concentrations, which led to low ER:HRasV12 intracellular levels; under these conditions FGF2 strongly promoted colony growth and PMA had no effect; c) furthermore, in HEK/ER:HrasV12 sublines, elevated 4-OHT concentrations led to high ER:HRasV12 intracellular levels and maximal colony growth; but, under these experimental conditions both FGF2 and PMA abolished colony growth. On the other hand, HEK293 transformation with a vector that constitutively express HrasV12 yielded HEK/ER:HrasV12 sublines displaying the following phenotypic traits: a) non FGF2 effects on proliferation and b) severe proliferation inhibition by PMA. PMA toxicity, exclusively observed in HrasV12 -transformed HEK293 cells, was characterized by: a) total dependency on PKC, likely mediated by specific proteolytic activation of PKCδ; b) involvement of high and sustained ROS levels correlated with late apoptosis triggering

Changes of gene methylation profile in malignant transformation of immortalized human bronchial epithelial cell line induced by alpha-particle irradiation / 中华放射医学与防护杂志

Objective To identify the changes of DNA methylation profile in the process of malignant transformation of BEP2D cell induced by α particles.Methods The genomic DNAs were isolated from the malignant transformation BERP35T4 cells and immortalized human bronchial epithelial cell line BEP2D.Genomic DNAs were digested by MseI and ligated of PCR linkers.Methylated DNAs were digested by BstUI and amplified by PCR.The methylated DNA probes were prepared by labeling with Cy3 and Cy5 fluorescence dyes individually and hybridized to the methylation CpG-Island microarray.The hybridization results were scanned and analyzed.Intensity values were quality controlled and normalized.The normalized data were used to identify the differentially expressed genes based on a 1.5 fold difference of the expression level.Results There were 16 genes which showed changes of methylation level in malignant transformation BERP35T4 cells, 9 of them were hypermethylation and 7 were hypomethylation.These genes were including the SKIP gene, PPP3CC gene, MAP2K6 gene, KIR2DL1 gene, KIR2DL4 gene, KIR3DP1 gene, ZNF493 gene, ZNF100 gene, NKX2-5 gene, TFAP2D gene, DR1 gene, KCNJ16 gene, CCDC18 gene, FNBP1L gene, IRX4 gene, EPB41L3 gene, TCP10 gene and so on.Conclusions The DNA methylation might have effects on ionizing radiation drived tumorigenesis.

Mechanism of cyclin-dependent inhibitor p27~(Kip1) in regulating the differentiation of immortalized human neural progenitor cells / 解剖学报

Objective To investigate whether there is any functional link between p27~(Kip1) function and all-trans retinoic acid (RA) in the control of neuronal differentiation of immortalized human neural progenitor cells (hSN12W-TERT cells). To investigate the mechanism by which p27~(Kip1) regulates the differentiation of immortalized human neural progenitor cells. Methods hSN12W-TERT cells were derived from the striatums of human embryos at 12 weeks gestation and cultured with serum-free medium in presence of EGF and bFGF. At the appropriated time, hSN12W-TERT cells were exposed to 1μmol/L RA for 3, 5, 7 days respectively. The experiment was repeated there times. Cell cycle analysis was performed by flow cytometry analysis (FACS). The expression of p27~(Kip1), p21~(cip1), cyclin-dependent kinase 2 (cdk2), p-cdk2 and S-phase kinase-associated protein 2 (skp2) in hSN12W-TERT cells before and after RA treatment cells were determined by using Western blotting analysis. Results FACS result showed that 77.25% of proliferating hSN12W-TERT cells were in the G1/G0-phase while 9.38% of cells in the S-phase. Following RA treatment, cell growth was arrested, and 85.68% of cells accumulated in G1/G0-phase while 8.57% of cells in the S-phase. Western blotting analysis demonstrated that the levels of p27~(Kip1) in the hSN12W-TERT cells increased following 3 days' treatment with RA compared with those of normal untreated cells, with a peak at 5 days (P<0.05). The similar results were acquired both in nuclear proteins and in cytoplasm proteins of hSN12W-TERT cells. The expression level of p21~(cip1) decreased in response to RA treatment. RA did not affect the expression of cdk2, but the expression of p-cdk2, which represented the activity of cdk2, was markedly decreased in response to RA treatment. Skp2, which was required for the ubiquitin-mediated degradation of p27~(Kip1), was detected in proliferating hSN12W-TERT cells. The expression of skp2 reduced dramatically in response to RA treatment in a time-dependent manner.Conclusion There is a functional link between RA and p27~(Kip1) function in the control of neuronal differentiation in hSN12W-TERT cells. P27~(Kip1) plays a key role during neuronal differentiation. Moreover, high levels of p27~(Kip1) are associated with its degradation inhibiting through reducing proteasome-dependent proteolysis.

Establishment of immortalized B lymphoblastoid cell lines of old residents in high background radiation area in Guangdong,China / 中华放射医学与防护杂志

Objective To establish the immortalized cell lines of peripheral blood lymphocytes for old male residents in high background radiation area(HBRA)in Guangdong,China,in order to preserve the specific genomic resources of residents in HBRA for the further genetic and molecular biological study on HBRA.Methods The peripheral blood samples of 20 old male residents in HBRA were collected after informed consent.The immortalized B lymphoblastoid cell lines,2 for each resident,were established with Epstein-Barr virus.After being frozen and recovered,the cell viability,the contamination of bacterium and mycoplaama were analyzed.The stabilization of cell lines was decided by comparing the karyotypes of the peripheral blood lymphocytes and the cell lines.Results 40 cell lines for 20 residents in HBRA were successfully established.The recovery rate of cell lines after being frozen was 100%.All the cell viablity after recovery was higher than 90%.and no contamination of bacteria and mycoplasma occurred.The karyotypes of the 20th generation cell lines were not change.Conclusion The immortalized cell lines established in this study could provide biological resources for further study on genetics and molecular biology in HBRA.

Evaluation of the radiopacity and cytotoxicity of resinous root canal sealers / 대한치과보존학회지

The aim of this study was to evaluate the radiopacity and cytotoxicity of three resin-based (AH 26, EZ fill and AD Seal), a zinc oxide-eugenol-based (ZOB Seal), and a calcium hydroxide-based (Sealapex) root canal sealers. Specimens, 10 mm in diameter and 1 mm in thickness, were radiographed simultaneously with an aluminum step wedge using occlusal films, according to ISO 6876/2001 standards. Radiographs were digitized, and the radiopacity of sealers was compared to the different thicknesses of the aluminum step wedge, using the Scion image software. Using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the cytotoxicity of each material was determined in immortalized human periodontal ligament (IPDL) cells. The results demonstrated that EZ fill was the most radiopaque sealer, while Sealapex was the least radiopaque (p 0.05). These results indicate that resin-based root canal sealer is more biocompatible and has advantage in terms of radiopacity.

Characterization of Immortalized Human Corneal Endothelial Cell Line using HPV 16 E6/E7 on Lyophilized Human Amniotic Membrane

PURPOSE: To establish the immortalized human corneal endothelial cell line (IHCEn) by transducing human papilloma virus (HPV) 16 E6/E7 oncogenes, and to identify their characteristics when cultivated on a lyophilized human amniotic membrane (LAM). METHODS: Primary human corneal endothelial cells (PHCEn) were infected using a retroviral vector with HPV 16 E6/E7, and transformed cells were clonally selected by G418. Growth properties and characteristics of IHCEn were compared with PHCEn by cell counting and RT-PCR of VDAC3, SLC4A4, CLCN3, FGF-1, Col IV, and Na+/K+ ATPase. IHCEn were cultured on LAM. Messenger RNA expressions of VDAC3, CLCN3, and Na+/K+ ATPase, and protein expressions of Na+/K+ ATPase and Col IV in IHCEn cultivated on LAM were investigated by RT-PCR, immunofluorescence, and immunohistochemical staining, respectively. RESULTS: Successful immortalization was confirmed by stable expression of HPV 16 E6/E7 mRNA by RT-PCR, and IHCEn exhibited typical corneal endothelial morphology. Doubling time of IHCEn was 30.15+/-10.96 hrs. Both IHCEn and PHCEn expressed VDAC3, CLCN3, SLC4A4, FGF-1, Col IV, and Na+/K+ ATPase. IHCEn cultivated on LAM showed stronger expression of VDAC3, CLCN4, and Na+/K+ ATPase mRNA than on plastic culture dish. Immunohistochemical staining and immunofluorescence revealed the positive expression of Na+/K+ ATPase and Col IV. CONCLUSIONS: IHCEn were successfully established, and LAM is a good substrate for the culture of human corneal endothelial cells.

The neurochemical properties of an immortalized glomus cell line from the carotid body of rat / 中华神经医学杂志

Objective Embryonic stem cells (ES) are potentially useful for treatment of Parkinson's disease. However, ES cells contain a mixed population of neurons, and selective enrichment of dopaminergic components remains difficult. Here, we report that a dopaminergic clonal cell line developed from carotid body. Methods Glomus cells of the rat carotid body were conditionally immortalized by retroviral transfer of the SV40 T antigen and Cre/lox P elements. The oncogene was subsequently removed adenoviral delivery of the Cre recombinase. Results Cloned glomus cells expressed high levels of tyrosine hydroxylase immunoreactivity and selectively released dopamine in culture. Remarkably, they expressed little dopamine transporter DAT, and were resistant to dopamine- and MPTP-mediated neurotoxicity. Conclusion Immortalized glomus cell line might provide an alternative way to the treatment of Parkinson's disease.

Dynamic Changes of B Cells Lymphocytes and Immortalized B Cells in Children with Infectious Mononucleosis / 实用儿科临床杂志

0.05),but the expression of CD19+ in the 3rd month and the 6th month were lower than that of healthy control group(Pa

Immortalized Rat Astrocyte Strain Genetically Modified by Rat Preprogalanin Gene / 华中科技大学学报（医学）（英德文版）

To construct an immortalized rat astrocyte strain genetically modified by rat preprogalanin gene (IAST/GAL) and detect its galanin (GAL) expression and secretion, a cDNA fragment of rat GAL in plasmid of pBS KS(+)-GAL was inserted into eukaryotic expression vector pcDNA3.1(+) by DNA recombinant technology, then the restriction enzyme digestion and DNA sequencing were carried out to evaluate the recombinant. The pcDNA3.1 (+)-GAL and pcDNA3.1 (+) construct were transfected into immortalized rat astrocyte strain (IAST) by lipofectamine and the population of cells which stably integrated the construct was selected with 600 μg/mL G418. Individual clones were screened and expanded into clonal cell strains. Detection of Neo gene was used to validate the success of the transfection. Immunocytochemical staining, RT-PCR and radioimmunoassay were used to detect the expression and secretion level of GAL. The recombinant had been successfully constructed by restriction enzyme digestion and DNA sequencing. Detection of Neo gene showed that the pcDNA3.1 (+)-GAL and pcDNA3.1 (+) have been successfully transfected into IAST. After selection by using G418, IAST/GAL and IAST/Neo cell strains were obtained.IAST/GAL, IAST/Neo and IAST were immunostained positively for GAL, but the GAL average optical density of IAST/GAL was significantly higher than that of IAST/Neo and IAST (P＜0.01). The level of GAL mRNA expression and the supernatant concentration of GAL in cultured IAST/GAL were significantly higher than those of IAST and IAST/Neo (P＜0.01), but no significant differences were found between the IAST and IAST/Neo (P＞0.05). It was concluded that IAST/GAL strain was constructed successfully and it might provide a basis for the further study of pain therapy.