To explore the molecular mechanism of human papillomavirus subtype 16(HPV-16)E7 oncogene-induced DNA re-replication in response to DNA damage. Flow cytometry was performed to examine the cell cycle changes in RPE1 E7 cells stably expressing HPV-16 E7 and its control cell RPE1 Vector after DNA damage.Immunoblotting assay was used to evaluate the early mitotic inhibitor 1(Emi1)expression in RPE1 E7 and RPE1 Vector cells with or without DNA damage.The changes of the proportion of polyploidy was detected by flow cytometry in DNA-damaged RPE1 E7 cells interfered by Emi1 small interfering RNA. Compared with the control cells,the proportion of polyploids in RPE1 E7 cells was significantly increased in response to DNA damage(=6.397,=0.0031).Emi1 protein expression was significantly increased in DNA damaged RPE1 E7 cells(=8.241,=0.0012).The polyploid ratio of RPE1 E7 cells was significantly reduced after Emi1 was interfered by two independent small interfering RNAs(=2.916,=0.0434;=3.452,=0.0260). In response to DNA damage,Emi1 promoted DNA re-replication caused by HPV-16 E7.
DNA Damage ; DNA Replication ; Human papillomavirus 16 ; Mitosis ; Oncogene Proteins, Viral

OBJECTIVETo study the possible mechanism of protective effect for Baicalin on Bacillus pertussis (BP) infected brain tissue and the dose-effect relationship.

METHODSBrain tissues slices were divided into 7 groups: (1) the normal group; (2) the model group: infected by 10% BP; (3) the baicalin group, which was pretreated with baicalin, infected by BP and subdivided into 5 sub-groups according to different doses of baicalin used; (4) the glutamic acid group: cultured with glutamic acid; (5) the baicalin plus glutamic acid group; (6) the peroxide group: cultured with hydrogen peroxide; and (7) the baicalin plus peroxide group. The lactate dehydrogenase (LDH) content in the supernatant of culture was determined and quantitative protein determination was conducted.

RESULTSThe LDH releasing was higher in the model group, glutamic acid group and peroxide group as compared with that in the normal group, 15.10 +/- 4.89 u/g. protein (the same unit below), 15.49 +/- 5.66 and 16.54 +/- 5.47 vs 6.10 +/- 2.87 respectively (P < 0.01). After being pretreated with 0.25 mmol/L baicalin, LDH level decreased significantly to 8.65 +/- 2.43, which was significantly different from that in the model group (P < 0.01), LDH was also decreased in the baicalin plus glutamic acid group (9.93 +/- 2.89) and baicalin plus peroxide group (9.54 +/- 2.82), which was significantly lower than that in the glutamic acid group and the peroxide group respectively (P < 0.01).

CONCLUSIONPretreatment of baicalin has protective effect on BP caused nerve cell injury in rat brain slices, the protection is possibly related with the reduction of glutamic acid and hydrogen peroxide induced damage on nerve cells in vitro.

Animals ; Anti-Bacterial Agents ; pharmacology ; Bordetella pertussis ; Brain ; cytology ; microbiology ; Coculture Techniques ; Culture Techniques ; Dose-Response Relationship, Drug ; Female ; Flavonoids ; pharmacology ; Glutamic Acid ; pharmacology ; Hydrogen Peroxide ; pharmacology ; Male ; Neuroprotective Agents ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley

Background Our previous study demonstrated that epigallocateehin-gallate(EGCG),an active ingredient of green tea,has protective effect on optical nerve after optic nerve crush.Astrocyte was proved to play key role in the repair of nerve tissue,but the influence of EGCG on astrocyte is unclear.Glial flbrillary acidic protein (GFAP) is a special marker for astrocyte. Objective The aim of this study was to investigate the effect of EGCG on the expression of GFAP in optic nerve tissue after optic nerve crush. Methods Seventy-two clean Wistar rats were randomly divided into normal control group,sham+EGCG group,optic nerve crush+normal saline group(vehicle group),optic nerve crush+EGCG group.Optic nerve crush models were established by clamping optical nerve for 60 seconds by minitype optic nerve clipper with the force of 40 gram.Only ocular tissue was cut in the rats in sham group.Normal saline solution or EGCG(25 mg/kg)was intraperitoneally injected daily for 5 days consecutively and orally administered(2 mg/kg)daily afterwards.The expression of GFAP in optic nerve was detected by immunohistochemistry and quantified by Western blotting analysis on day 7,14 and 28 after modeling. Results lmmunochemistry showed that GFAP were weakly expressed in the rats of both normal group and sham+EGCG group with the sliSht brown staining in optic nerve tissue.The deeply brown staining for GFAP was seen in vehicle group,and the staining intensity weakened in optic nerve crush+EGCG group compared to vehicle group on days 7,14 and 28 after modeling.Western blotting analysis revealed that the expression level of GFAP in rat optic nerve tissue of vehicle group was significantly enhanced in comparison with normal control group(P＜0.01).On day 7 and 14 after optic nerve modeling,the expression levels of GFAP were evidently decreased in optic nerve crush+EGCG group in comparison with vehicle group(P＜0.05).However,on day 28 after modeling,no significant difference wag found in the expression levels of GFAP between vehicle group and optic nerve erush+EGCG group(P＞0.05). Conclusion EGCG down-regulates optic nerve crush-induced of GFAP in the optic nerve and therefore attenuates the activity of astrocytes,suggesting that EGCG might reduce the formation of glial scar.

Background Researches demonstrated that epigallocatechin-3-gallate(EGCG) can protect retinal ganglion cells(RGCs) against damage induced by retinal ischemia-reperfusion and optic nerve crush(ONC),but the effect of EGCG on lateral geniculate nucleus(LGN) was under study.Objective This study was designed to detect neuroprotective effect of EGCG on LGN in the rat model with ONC.Methods Forty-eight 7-week-old female clean Wistar rats were randomly divided into normal control group,sham operation+EGCG group,ONC+normal saline(NS) group and ONC+EGCG group.ONC models were created by clamping the optical nerve for 60 seconds with the clipper with the force of 40 grams in the right eyes of 24 rats.The EGCG solution(25mg/kg) was intraperitoneally injected from 2 days before operation daily for 5 consecutively days and orally administered(2mg/kg) after that,and NS was used in the same way for ONC+NS group.Four weeks after ONC,the brain tissue of the rats was obtained,and the neurons of dorsal LGN(dLGN) were counted by Nissl staining under the light microscopy.The expression of neurofilament triplet L(NF-L) was detected by immunohistochemistry and Western blot analysis.Meanwhile,the neuronal nitric oxide synthase(nNOS) positive cells were counted.Results Compared with normal control group,no significant differences were found in neuron number both between sham operation+EGCG group or ipsilateral LGN of operative eyes in ONC+normal saline group and ONC+EGCG group(P=0.906,0.561,0.794,0.646 respectively) in 4 weeks after ONC,but loss of neurons in contralateral LGN in both ONC+normal saline group and ONC+EGCG group were observed(P=0.000,0.015 respectively).However,compared with ONC+normal saline group,the density of neurons in ONC+EGCG group was higher(P=0.007).Moreover,a higher expression level of NF-L protein was seen in ONC+EGCG group compared with ONC+normal saline group at contralateral LGN of operative eyes(P=0.002).Concerning the number of nNOS positive cells in LGN,there was no significant difference among normal control group,sham operation+EGCG group and ONC+EGCG group(P＞0.05).The number of nNOS positive cells in the contralateral LGN of operative eyes of ONC+normal saline group was higher than that of ONC+EGCG group(P=0.000).Conclusion EGCG plays the protective effect on LGN after ONC in rats through mediating the expression of nNOS.

Objective To explore the effects of under-expression of large tumor suppressor 1 (LATS1) on activation of Hippo signaling pathway and differentiation, proliferation, migration of bone marrow mesenchymal stem cells (mMSCs) of micein vitro.Methods mMSCs of C57BL/6 mice were divided into normal control (MSC) group, empty vector control (MSC-GFP) group, LATS1-over-expressing (MSC-LATS1) group, empty vector without LATS1 shRNA control (MSC-shControl) group and LATS1-under-expressing (MSC-shLATS1) group. Lentiviral vectors with activated,inactivated LATS1 (the key molecule of Hippo signaling pathway) modifications and empty vectors were constructed and were used to infect mMSCsin vitro. The transduction efficiencies mediated by the lentiviral vectors were evaluated by fluorescence microscopy and flow cytometry. The mRNA expression of LATS1 was quantified by quantitative real-time polymerase chain reaction (qRT-PCR), and the protein expressions of LATS1, YAP (p-YAP), 14-3-3 were quantified by Western Blot to evaluate the activation of Hippo signaling pathway. Osteogenic and adipogenic differentiation of mMSCs were evaluated through measurement of Runx2, OSX and C/EBPα, PPAR-γ mRNA by qRT-PCR, as well as Alizarin Red S and Oil red O staining. Proliferation of mMSCs was evaluated using methy thiazdyl tetrazolium (MTT) assay. The scratch test and Transwell chamber test were used to analyze the horizontal and vertical migration ability of mMSCs.Results The transduction efficiencies mediated by the lentiviral vectors were 94.74%-96.10%. Compared with MSC-GFP group, the activation of Hippo signaling pathway was promoted in MSC-LATS1 group [LATS1 mRNA (2-ΔΔCT): 4.37±0.21 vs. 1.20±0.04, LATS1 protein (gray value): 2.21±0.06 vs. 1.09±0.10, p-YAP/YAP protein (gray value): 1.51±0.13 vs. 0.98±0.05, 14-3-3 protein (gray value): 1.92±0.18 vs. 1.10±0.09, allP < 0.05], osteogenic and adipogenic differentiation of mMSCs were decreased in MSC-LATS1 group [mineralization (A value):0.13±0.02 vs. 0.40±0.03, Runx2 mRNA (2-ΔΔCT): 0.51±0.02 vs. 0.98±0.09, OSX mRNA (2-ΔΔCT): 0.41±0.04 vs. 1.04±0.09, lipid accumulation (A value): 0.10±0.02 vs. 0.25±0.03, C/EBPα mRNA (2-ΔΔCT): 0.33±0.03 vs. 1.11±0.09, PPAR-γ mRNA (2-ΔΔCT): 0.29±0.02 vs. 1.04±0.10, allP < 0.05], the proliferation rate of mMSCs at 4-7 days was decreased in MSC-LATS1 group and so were the horizontal and vertical migration of mMSCs [wound healing rate: (18.65±3.53)% vs. (40.29±1.87)%, migrated cells (cells/MP): 35.99±6.18 vs. 103.67±17.77, bothP <0.05]. Compared with MSC-shControl group, the activation of Hippo signaling pathway was inhibited in MSC-shLATS1 group [LATS1 mRNA (2-ΔΔCT): 0.16±0.01 vs. 0.98±0.03, LATS1 protein (gray value): 0.38±0.03 vs. 1.04±0.07, p-YAP/YAP protein (gray value): 0.58±0.04 vs. 1.05±0.06, 14-3-3 protein (gray value): 0.14±0.02 vs. 1.02±0.09, allP < 0.05], osteogenic and adipogenic differentiation of mMSCs were increased in MSC-shLATS1 group [mineralization (A value): 0.93±0.13 vs. 0.44±0.05, Runx2 mRNA (2-ΔΔCT): 1.44±0.12 vs. 0.95±0.04, OSX mRNA (2-ΔΔCT):1.67±0.06 vs. 1.10±0.11, lipid accumulation (A value): 0.47±0.06 vs. 0.28±0.04, C/EBPα mRNA (2-ΔΔCT):3.98±0.61 vs. 0.99±0.10, PPAR-γ mRNA (2-ΔΔCT): 3.05±0.36 vs. 0.98±0.14, allP < 0.05], the proliferation rate of mMSCs at 3-7 days was increased in MSC-shLATS1 group and so were the horizontal and vertical migration of mMSCs [wound healing rate: (80.18±6.98)% vs. (46.18±1.01)%, migrated cells (cells/MP): 212.69±41.21 vs. 115.87±35.15, bothP < 0.05].Conclusions Under-expression of LATS1 promotes the differentiation, proliferation, migration of mMSCs by inhibition of Hippo signaling pathwayin vitro.

The strain Acidiphilium cryptum DX1-1 producing PHB was irradiated respectively by UV and Co60 to raise PHB production. The results indicated that the effect of UV better than using Co60. One strain of the UV mutagenized called UV60-3 has the highest PHB production yield, showing final PHB concentra- tion of 28.56 g/L, 1.45 times higher than that of original strain. FT-IR spectroscopy analysis shows that the polymers obtained from the strain DX1-1 have the same IR spectra of standard PHB. Further research about the best appropriate C/N ratio of the mutant was done. The optimum ratio of C/N was about 3.76, the final PHB concentration reaches to 30.57 g/L.

The aim of this study was to investigate the effect of Celastrol on induction of HL-60 cell apoptosis and its possible mechanism. The proliferative activity of HL-60 cells treated with 0.25 - 8.0 μmol/L of Celastrol for 24 - 72 hours was assayed by MTT method, the effects of Celastrol on apoptosis and cell cycle of HL-60 were detected by TUNEL staining and flow cytometry with Annexin V-FITC/PI double labeling, the expression of pAkt and cyclin D1 at protein and gene level in HL-60 cells treated with Celastrol were measured by Western blot and RT-PCR. The results showed that the Celastrol could obviously inhibit the proliferation of HL-60 cells in concentration-and time-dependent manners, the IC₅₀ value of Celastrol for 24 hours was 6.21 ± 0.242 μmol/L. The Celastrol concentration-dependently induced the apoptosis of HL-60 cells, accompanying with morphological changes of apoptotic cells, which may be related with arrest of cells in G₀/G₁ phase. The Celastrol suppressed the expression of pAkt and Cyclin D1 in HL-60 cells to a varying degree which showed obvious concentration-and time-dependent manners. It is concluded that the Celastrol inhibits the proliferation and induced the apoptosis of HL-60 cells. Its mechanism may be related with down-regulation of p-Act and cyclin D1 expressions.
Apoptosis ; drug effects ; Cyclin D1 ; metabolism ; Down-Regulation ; Gene Expression Regulation, Leukemic ; HL-60 Cells ; Humans ; Proto-Oncogene Proteins c-akt ; metabolism ; Triterpenes ; pharmacology

BACKGROUND: Human umbilical cord mesenchymal stem cells (hUC-MSCs) have low immunogenicity and it is unclear whether insulin producing cells (IPCs) that differentiate from hUC-MSCs have low immunogenicity. OBJECTIVE:To investigate the immunogenicity of IPCs differentiating from hUC-MSCs in vitro and after IPCs transplantation into the host. METHODS: (1) The hUC-MSCs were induced to differentiate into IPCs according to the modified scheme. Flow cytometry assay was used to detect the immunophenotype and apoptotic rate of IPCs in a cytotoxicity test. (2) Cell counting kit-8 was used to detect the proliferative capacity of human peripheral blood mononuclear cells in the one-way mixed lymphocyte assay. (3) The IPCs were then transplanted into the abdominal cavity and left renal capsule of mice, and then the infiltration of immune cells was detected by flow cytometry and immunohistochemistry. RESULTS AND CONCLUSION: The IPCs highly expressed HLA-ABC and lowly expressed HLA-DR, CD40 and CD80. The apoptosis rate of IPCs increased with the increase of pre-sensitized splenocytes in the cytotoxicity test. In the one-way mixed lymphocyte assay, IPCs inhibited the proliferation of human peripheral blood mononuclear cells when the target ratio was 10:1 and 50:1. After IPCs transplantation, the number of lymphocytes was increased in the transplanted site. In summary, our results show that IPCs that differentiate from hUC-MSCs maintain low immunogenicity in vitro,but have some immunogenicity after transplantation into the host due to microenvironment changes.

Objective To establish rat models of polycystic ovary syndrome(PCOS) induced by different methods,to assess the serum levels of several related hormones,to examine the morphological changes in the ovaries,and to discuss their significance.Methods Letrozol,sodium prasterone sulfate,or sodium prasterone sulfate combined with human chorionic gonadotropin were used to establish rat models of PCOS.Radioimmunoassay was used to measure the serum levels of hteinizing hormone(LH),follicle-stimulating hormone(FSH),estrogen(E_2),progesterone(P),testosterone(T),prolactin(PRL),and insulin(INS).HE staining was used to examine the morphological changes of the ovaries.Results Comparing with the normal group A,the serum FSH was increased and the serum progesterone was reduced in the group B,with a statistically significant difference(P<0.05).The serum testosterone was significantly higher in the group B than in the group A(P<0.01).The levels of serum sex hormones and insulin were not significantly different in the group D and C(P>0.05).In comparison with the group C,the levels of serum testosterone and LH/FSH ratio was significantly increased in the group E.(P<0.05).Comparing with the group D,the serum levels of progesterone and testosterone were significantly increased in the group E(P<0.05).The ovaries in the rats of groups A and C showed almost a normal histyology,with mature follicles and dominant follicles.Polycystic changes were observed only in the ovaries of groups B,D and E.Conclusion At the aspect of affecting the level of sex hormones in serum and changing the ovarian morphology.adopting letrozol tablets or sodium prasterone sulfate combined with HCG to induce rat PCO model is more close to clinic manifestations and meets the criteria of PCO animals.In the rat PCOS models induced with letrozol or with sodium prasterone sulfate combined with HCG,either the serum levels of sex hormones and ovarian histology are quite similar to those of human clinical appearance,and may well meet the modeling requirements for future experimental studies of polycystic ovary syndrome.

Objective The hearing and speech rehabilitation effects by hearing aid use and cochlear implanta‐tion in hearing -impaired children were compared .Methods A total of infants aged from 6 months to 3 years with severe hearing loss of prelingual nature were included .They were divided into 2 groups :group 1 (18 with hearing aids) and group 2 (14 with cochlear implantation) .There was no significant difference in the degree of hearing loss and age between the 2 groups .They received rehabilitation education of the same content for a year .Their unaided and aided thresholds were tested in sound field while the IT -MAIS was used for evaluating hearing ability of two groups before and after 3 ,6 ,9 ,and 12 months of hearing aid use and cochlear implantation .Results In both groups ,hearing were better in aided conditions than those of in unaided ,while those from the cochlear group were significantly improved at more frequencies than those of the hearing aid group .In general ,the longer use and train‐ing ,the better hearing improvement .The mean scores of auditory performance in the cochlear implantation group at 6 months were significantly higher in comparison with those at 3 months (P<0 .05) .There were significant differ‐ences in mean scores between the two groups at 6 ,9 ,12 months after fitting (P<0 .05) .The verbal ability scores ,hearing and speech rehabilitation levels in the cochlear group were higher than those of in the hearing aid group (P<0 .05) .Conclusion For severe hearing loss children ,cochlear implantation could produce more noticeable effects than hearing aids .