Primary liver cancer is one of the common malignant tumors.However, the efficacy of traditional treatments is not satisfactory.RNA interference is a new treatment method, which develops rapidly in recent years.It has been found that RNA interference can exert the anti-tumor effect through inhibiting the growth and proliferation of hepatocarcinoma cells, promoting apoptosis, inhibiting the invasion and metastasis of hepatocarcinoma cells, inhibiting angiogenesis and overcoming the resistance to chemotherapy.

Objective:To study the role of 14-3-3εand Cdc25B in germinal vesicle (GV)-stage arrest of mouse oocytes,and to pay foundation for further study on the molecular mechanism of PKA/Cdc25B/14-3-3εpathway in GV-stage arrest of mouse oocytes.Methods:The eukaryotic expression vectors of pcDNA3.1-ZEO-HA-14-3-3ε, pcDNA3.1-MYC-Cdc25B-WT, pcDNA3.1-MYC-Cdc25B-S321A, and pcDNA3.1-MYC-Cdc25B-S321D were transcribed into mRNA invitro.The mouse GV-stage oocytes were collected after superovulation and divided into no injection group,TE buffer microinjection group,14-3-3εmRNA injection group,14-3-3εmRNAs + Cdc25B-WT mRNA injection group,and 14-3-3εmRNA + Cdc25B-S321A mRNA injection group,14-3-3εmRNA+Cdc25B-S321D mRNA injection group.The protein expression levels of HA-14-3-3εand MYC-Cdc25B and the phosphorylation status of Cdc2-pTyr15 were observed by Western blotting method.The morphological changes and germinal vesicle breakdown (GVDB)rates of mouse oocytes were observed under phase-contrast microscope. Results:None of the oocytes in no injection group, TE buffer microinjection group, 14-3-3εmRNA injection group,14-3-3εmRNA + Cdc25B-WT mRNAs injection group and 14-3-3εmRNA + Cdc25B-S321D mRNA were able to undergo GVBD until at least 20 h after injection (P>0.05 );the GVBD rates of oocytes in 14-3-3εmRNA+Cdc25B-S321A mRNA group at 1 h (5.00%±0.68%),2 h (62.00%±3.56%)and 3 h (100.00%± 0.00%)after injection were significantly higher than those in no injection group and TE buffer injection group (P<0.01);the oocytes in 14-3-3εmRNA+ Cdc25B-Ser321A mRNA group at 20 h (79.00%±2.80%)after injection progressed to MII (P<0.01).Conclusion:14-3-3εcan regulate the transition from GV to GVBD of mouse oocytes by means of phosphorylation and dephosphorylation of S321-Cdc25B.

Objective To observe the effects of sevoflurane and propofol on cerebral oxygen metabolism and postoperative cognitive function during cardiopulmonary bypass (CPB). Methods Fifty ASA Ⅱ or Ⅲ patients aged 40-65 years old scheduled for cardiac valve replacement surgery with CPB were randomly assigned into two groups,sevoflurane group (group S) and propofol group (group P),25 in each group.Two groups of patients used the same method of anesthesia induction:midazolam 0.1 mg?kg-1,sufentanil 0.7 μg?kg-1,vecuronium 0.1 mg?kg-1,and etomidate 0.2 mg?kg-1 were intravenously injected successively,and then tracheal intubation was performed.For maintenance of anesthesia,patients of group S continuously inhaled 3%-4% sevoflurane, and patients of group P were intravenous pumped with propofol 4-6 mg?kg-1?h-1 via vein;midazolam,sufentanil and vecuronium bromide were intermittently injected in both groups.At the time points of pre-bypass (t1), nasopharynx temperature dropping to constant temperature regularly ( t2 ) ,nasopharynx temperature rising to constant temperature regularly ( t3 ) ,1 h after the end of CPB ( t4 ) ,and 6 h after the end of CPB ( t5 ) ,blood from radial artery and right jugular bulb was harvested for blood gas analysis,and mini-mental state examination( MMSE) score were evaluated before and 24 and 48 h after the surgery. Results The jugular venous bulb oxygen saturation( SjvO2 ) in the two groups were both increased during T2 period and then decreased during t3 period, but arteriovenous oxygen content difference ( AVDO2 ) and oxygen extraction rate (O2ER) were both decreased during t2 period and then increased during t3 period.There was no significant difference between the two groups during t2 and t3 period (P>0.05).MMSE scores of the two groups after operation were all less than those before operation,but that was significantly higher in the sevoflurane group than in the propofol group 24 h after the surgery ( t=4.34,P<0.05) . Conclusion The two anesthesia methods can meet the need of valve replacement surgery and maintain the cerebral oxygen balance during CPB period, but sevoflurane anesthesia has fewer influences in post-operation mental nerve functional changes.

Objective to probe into whether head-simulator teaching can enhance tooth cavity preparation compared with traditional preclinical teaching program.Method Questionnaires were conducted among the Grade 2002 students who had been trained by head-simulator teaching and were practicing in oral cavity section of our school.Result Majority of students think it's a good method and they have got better results than those trained in traditional experiment teaching.Conclusion The head-simulator teaching has improved the teaching quality of tooth cavity preparation but there exist some disadvantages which need further improvement and extension.

Objcetive To investigate the protective effects of the nitroxides R-1 on human liver cells exposed to ionizing radiation.Methods Human liver cells L-02 were cultured and irradiated with 60Co γ-rays at the doses of 0,1,2,4,and 8 Gy,in order to screen the proper irradiation dose.WR2721 at the terminal concentration of 4 mmol/L was used as positive control.L-02 cells irradiated with 4 Gy were added with R-1 at the terminal concentration of 0.25 μmol/L at 30 min before irradiation or immediately after irradiation.MIT method was used to screen the proper conditions for follow-up experiment 72 h later.L-02 cell culture fluid was added with R-1 at the concentrations of 0,0.125,0.25,0.5,and 1 μmol/L,respectively for 30 min before irradiation at the doses of 0,1,2,4,and 8 Gy to ealculate clone formation rate at 10 d post-irradiation.L-02 cells were cultured and divided into 4 groups:control group without any treatment.drug group pretreated by 0.25 μmol/L R-1 only,irradiation group,irradiated at 4 Gy only,and drug + irradiation group with combination of 0.25 μmol/L R-01 and 4 Gy irradiation.The inverted microscopy and Hoechst 33258 staining and flow eytometry were used to observe the apoptosis of the cells at 24,48,and 72 h later.Results Nitroxides R-1 did not inhibit the viability of L-02 cell when its concentration was less than 1 μmol/L and it inhibited the L-02 cell growth when the concentration wu higher than 2 μmoL/L.The A value and colony formation rate of different concentration of R-1 groups were all higher than those of the irradiation group,and the effect of the 0.25 μmol/L drug concentration group was the most significant.Consequently,the concentration 0.25 μmoL/L was selected for follow-up experiment.Compared with the irradiation group,the L-02 cells of the pretreatment group showed solid adherence, increased refraction,clear outline,less apoptotic and dead cells at 4 Gy post-irradiation.Conclusions Nitroxides R-1 can protect the human liver cells from 60Coγ-ray induced injury effectively.The mechanism of its protective effect may be the reduction of apoptosis.

BACKGROUND:Studies have found that epithelial-mesenchymal transition is closely related with tumor invasion, metastasis, and drug resistance, but studies on the role of epithelial-mesenchymal transition in the transformation process of gastric cancer cels SGC7901 to gastric cancer stem-like cels are rarely reported.
OBJECTIVE: To explore the effect of epithelial-mesenchymal transition in the transformation process of gastric cancer cels SGC7901 to gastric cancer stem-like cels.
METHODS:Vincristine-induced SGC7901 cels were cultured and screened to prepare gastric cancer stem-like cels. CD44 phenotype, morphological changes, stem cel-related markers, and epithelial-mesenchymal transition related molecules were detected.
RESULTS AND CONCLUSION:After passage, vincristine-induced SGC7901 cels presented with morphological changes, and clonal cel spheres generated after serum-free suspension culture. Meanwhile, the proportion of SGC7901 cels positive for CD44 was decreased. Expression levels of SOX2, OCT4, Snail1 mRNA, Twist mRNA and Vimentin mRNA were significantly higher in the gastric cancer stem-like cels than SGC7901 cels, but the expression level of E-caderin was lower in the gastric cancer stem-like cels than SGC7901 cels. These findings indicate that gastric cancer cels SGC7901 can be successfuly transformed into gastric cancer stem-like cels, and the epithelial-mesenchymal transition is involved in this transforming progress.

BACKGROUND:Choosing internal fixator implants with good strength and stiffness is the key to repair femoral neck combined with ipsilateral subtrochanteric fractures. OBJECTIVE:To compare the biomechanical properties of different implant fixation for femoral neck combined with ipsilateral subtrochanteric fractures. METHODS:Totaly 24 adult antiseptic cadaver specimens were used to produce fracture models with femoral neck fracture combined with 5 cm of ipsilateral subtrochanteri medical cortical defect, and were divided into femoral proximal locking plate group, lengthening proximal femur anti-rotation intramedulary nail group and lengthening proximal femoral nail group according to the random number table method. The results of axial compression test, torsion test and axial compression failure rest in three groups were compared. RESULTS AND CONCLUSION: The axial compressive stiffness and failure load in lengthening proximal femur anti-rotation intramedulary nail group were significantly greater than those in femoral proximal locking plate group and lengthening proximal femoral nail group, and those in lengthening proximal femoral nail group were significantly greater than those in femoral proximal locking plate group (P < 0.05). The torsional stiffness in femoral proximal locking plate group was significantly greater than that in lengthening proximal femur anti-rotation intramedulary nail group and lengthening proximal femoral nail group, and that in lengthening proximal femur anti-rotation intramedulary nail group was significantly greater than that in lengthening proximal femoral nail group (P < 0.05). The indexes of biomechanical properties of specimens at the 4thand 8th weeks after fixation in three groups were slightly increased compared with those in 0 week after surgery, but the difference was no statisticaly significant (P > 0.05). These results demonstrate that to a certain extent, compared with the femoral proximal locking plate and lengthening lengthening proximal femoral nail, lengthening proximal femur anti-rotation intramedulary nail fixation for repair of femoral neck combined with ipsilateral subtrochanteric fractures has more biomechanical advantages.

AIM: To investigate the effect of advanced glycosylation end products(AGEs) modified protein on morphological changes of actin cytoskeleton in primary endothelial cells and the role of MAPK signaling pathways in this pathological procedure.METHODS: Human umbilical vein endothelial cells(HUVECs) were incubated with AGEs modified human serum albumin(AGE-HSA) at concentrations of 12.5,25,50,and 100 mg/L,respectively,for 2,4,8,12 and 24 hours.The cells were treated with different chemical compounds of inhibitors,or adenoviral deliver approach(either dominant positive or negative adenoviral constructs) of MAP kinases to specifically block or activate certain signal transduction pathways under above situations.As control,HSA of the same concentration was administered to cells at the same time.The treated cells were incubated with FITC-phalloidin to stain F-actin.RESULTS: F-actin in HUVECs was rearranged greatly by AGEs in a concentration and time-dependent manners.The unmodified HSA did not influence Factin distributions.The AGEs-induced changes were blocked by pretreatment with SB203580,PD98059 for 30 min,or pre-infection with recombinant virus of dominant negative form of MKK 6b [MKK6b(A)],MEK1 [MEK1(A)] for 24 h,while SP600125 and dominant negative form of MKK7 [MKK7(A)] failed to inhibit the effects of AGEs.Furthermore,the infection of recombinant virus of constitutive active form of MKK6b [MKK6b(E)] or MEK1 [MEK1(E)] could also induced re-arrangement of F-actin,respectively,while the effect elicited by [MKK6b(E)] was abolished by co-infection with recombinant adeno-virus of dominant negative p38?. CONCLUSION: AGEs-induced morphological changes of F-actin in endothelial cells are mediated by p38-and ERK MAPK signal pathways.

Objective To explore the duration of blood blocking effect and recovery process induced by low-frequency ultrasound combining microbubbles (USMB) on prostate cancer xenografts.Methods A total of 88 nude mice undergoing USMB was studied.Contrast enhanced ultrasound,Hemotoxylin and eosin staining,and modified Martius-Sarlet-Blue staining were used to compared the average peak intensity(API),time to peak intensity(TP) and histological alteration before and after treatment.Results Immediately after the treatment,the tumor contrast perfusion completely disappeared,API dropped from 68.63±5.25 to 18.01±2.73 (P<0.001,vs pre-treatment) and TP increased from (32.28±6.18)s to (72.63±7.47)s (P<0.001,vs pre-treatment).At 30 minutes and 1 hour after treatment,the tumor perfusion remained defect.At 2 hours after treatment,rarely dotted enhancement was showed.The differences among the three groups in API and TP at 30 minutes,1 hour and 2 hours after treatment were not significant (all P>0.05).From post-3 hours after treatment ,the tumor perfusion began a process of perfusion recovery,and showed nodular or large patch of heterogeneous enhancement.API at 3 hours after treatment was 51.99±6.20 (P<0.001,vs post treatment immediately),and TP decreased to (50.41±6.51)s (P<0.001,vs post treatment immediately).At 4 hours,5 hours,6 hours,12 hours and 24 hours after treatment ,CEUS showed homogeneous and rich enhancement,and there was no significant difference in both API and TP,compared with those pre-treatment (all P>0.05,vs pre-treatment).Histological examinations showed that,immediately after treatment,microvessels severely dilated,ruptured and intravascular and extravascular thrombi formed.At 30 minutes,1-hour and 2-hour after treatment,extravascular thrombi and hematomas gradually disappeared.From 3-hour after treatment,vessel dilation was lessened,and intravascular thrombi gradually shrank.At 12-hour after treatment,microvessels had almost fully recovered as pre-treatment.Conclusions USMB could block blood perfusion of prostate cancer xenografts in nude mice for 2 hours.The blood reperfusion is probably mainly caused by thrombolysis in microvessels.

Objective To investigate the clinical characteristics,distribution and drug sensitivity of pathogens causing intravenous catheter-related bloodstream infections (CRBSIs) in pediatric intensive care unit (PICU) so as to use antibiotics reasonably.Methods All patients with CRBSIs in PICU of Guangdong General Hospital from September 2009 to September 2014 were investigated and the drug resistance profiles of pathogens causing CRBSIs were also analyzed retrospectively.Results Between 2009 and 2014,there were totally 10 834 catheter days and 23 episodes of CRBSIs with an incidence of 2.1 infections per 1 000 catheter days.Catheter indwell time ＜ 7 days in 9 cases (39.1％),8 to 14 days in 10 cases (43.5％),14 to 21 days in 4 cases (17.4％).There were 13 strains (56.6％) of gram-positive bacteria,5 strains (21.7％) of gram-negative bacteria and 5 strains (21.7％) of fungi.The main pathogens causing CRBSIs were coagulase negative Staphylococci (7 strains,30.4％),Staphylococcus aureus (3 strains,13.0％),Candida albicans(3 strains,13.0％),Candida parapsilosis(2 strains,8.7％),and Enterobacter cloacae (2 strains,8.7 ％).The susceptibility to Vancomycin,Linezolid and Teicoplanin of coagulase negative Staphylococ cus such as S.epidermidis and to Imipenem,Piperacillin/Tazobactam,Cefoperazone/ Sulbactam and Amikacin of gram-positive bacteria arrived at 100.0％,respectively.The candida were 100％ susceptible to Amphotericin B,5-Flucytosine,Fluconazole and Voriconazole.Twenty-one cases (91.3％) received antibiotic treatment versus no antibiotic in 2 cases (8.7％).The average number of antibiotic kinds administered on the patients with fungal infection was 4.4,bacteria were 1.4.Ten cases (43.5％) treatment with 1 kind of antibiotic,4 cases (17.4％) with 2,4 cases (17.4％) with 3,5 cases (21.7％) with more than 3.Twenty-two cases (95.7％) cured and 1 case died (4.3％).Conclusions The major species of pathogen causing CRBSIs was coagulase negative staphylococci in PICU.It is critical for clinicians to guard against fungal infection because of prolonged catheter indwelling time and more antibiotics administered before indwelling catheter.It is effective way to prevent the CRBSIs by reasonably using antibiotics and shortening the time of catheter indwelling.Monitoring CRBSIs pathogenic bacteria distribution and drug susceptibility helps reasonable administration of antibiotics in the earlier time.