Objective To investigate the influence of Smac to the chemosensitivity of cyclophosphamide (CTX) and doxorubicin (DOX) in MCF-7 cells.Methods MCF-7 cells were exposed to CTX,DOX and the combination of both.3-(4,5-dimethyl-2-thiazoly)-2,5-diphenyl-2 H-tetrazolium bromide (MTT) assay was used to estimate the cell viability.Apoptosis was measured by acridine orange staining and Ho.33342/PI dou-ble staining.The mRNA and protein expressions of Smac were determined by RT-PCR and Western blotting.The study also analyzed the changes of pro-apoptotic proteins active caspase-3 and active caspase-9.Results CTX,DOX and the combination of both drugs reduced the cell survival rates in a concentration-dependent manner.The cell viability after being treated with 4.0 μg/ml CTX or 0.2 μg/ml DOX or 2.0 μg/ml CTX and 0.1 μg/ml DOX for 48 hours was (52.90 ± 8.78) ％,(53.35 ± 6.29) ％ and (34.19 ± 5.43) ％,respectively.The drug combination developed a stronger inhibitory effect compared to the single drugs (t =9.051,P=0.014;t =9.074,P =0.014).The Smac mRNA and protein levels in 2.0 μg/ml CTX and 0.1 μg/ml DOX group were 7.47 ± 0.82 and 4.13 ± 0.36,which were higher than those in 4.0 μg/ml CTX group (3.27 ± 0.40 and 2.28 ± 0.27;t =-50.120,P =0.000;t =-42.588,P =0.000) and 0.2 μg/ml DOXgroup (3.34±0.62and2.45±0.40;t=-46.233,P=0.000;t=-39.541,P=0.000).Furthermore,pro-apoptotic proteins active caspase-3 and active caspase-9 increased activity was confirmed by Western blotting.Conclusion Smac plays a vital role in enhancing the sensitivity of chemotherapeutic drugs CTX and DOX in MCF-7 cell line.

BACKGROUND:Acellular dermal matrix possesses good flexibility and simple trimming.The intracutaneous or subcutaneous injection of acellular dermal matrix powder has fibroblast migration and collagen deposition.It has been widely used in plastic and reconstructive surgery.OBJECTIVE:To explore the feasibility of reconstructed acellular dermal matrix as a scaffold for chondrocyte implantation.DESIGN,TIME AND SETTING:Comparative observation.The study was performed at the Peking University Medical Department and Beijing Jishuitan Hospital between August 2003 and February 2007.MATERIALS:Neonatal calf dermis was provided by Beijing Yuanheng Shengma Biology Technology Research Institute.A total of 24 healthy adult SD rats,weighing 250 g,regardless of gender,and 36 New Zealand rabbits,aged 3 months,were selected.METHODS:①Calf full-thickness back skin was incubated with cell free buffer or ABS/AES for decellularization,followed by surface modification using growth factors.②Three rectangle skin flaps at two sides of the spinal cord of rats were made,and implanted with acellular dermal matrix.The implants were harvested at 2,6,and 12 weeks postoperatively.③The rabbits were divided into experimental and control groups.The cartilage was obtained from the left articular facet to isolate chondrocytes.The chondrocytes were seeded on the acellular dermal matrix.The cartilage defect was made on the right hind limb of experimentalrabbits,and implanted with acellular dermal matrix containing autoiogous chondrocytes.Biogel wass dropped on the surface of carrier.In the control group,the cartilage defect was made on the right hind limb of rabbits and the wound was sutured.Two rabbits from control group and 5 from experimental group were selected respectively at 4,12 and 24 weeks postoperatively.MAIN OUTCOME MEASURES:Cross-linking effect comparison;repair effect of rabbit bone defects.RESULTS:①The acellular dermal matrix cross-linked by glutaraldehyde demonstrated an obvious inflammatory reaction with tissue bleeding and necrosis.Conversely,ADM treated with water-soluble cross-linking agent caused displayed good histocompatibility.②The cartilage defects were repaired completely;the attached cells survived and proliferated and the acellular dermal matrix was degraded after 24 weeks of surgery.CONCLUSION:The acellular dermal matrix decellularized with cell free buffer,digested with digestive buffer,Cross-linked by water-soluble cross-linking agent,and further decorated with growth factor exhibited good histocompatibility,and was suitable forcell attachment and growth.The acellular dermal matrix scaffold almost degrades in the rabbits,with no rejection,and the bone defects were repaired after 24 weeks.

Objective To analyze the clinic characteristics, lifetime and prognostic factors of young female breast cancer patients. MethodsClinical data of 155 patients under 35 years of age with breast cancer were retrospectively reviewed and followed up.ResultsThe positive rate of hormone receptors was 61.6 % (77/125) in all cases who had been detected receptor status. The median survival time in hormone receptors positive and negative group were 119.0 and 51.3 months (P＜0.01), and 5-year survival rates were 68 % and 33 %, respectively. For patients who had been treated with adjuvant tamoxifen (47.1%), the median survival time was 182 months which longer than without tamoxifen (P ＜0.05). The median disease-free survival time and median survival time were 24 and 91 months in all cases. The overall 3-, 5- and 10-year survival rates were 79 %, 60 % and 51%, respectively. Multifactor analysis with the COX model indicated that tumor size, axillary metastatic status, tamoxifen treatment and overexpression of Her-2 were independent prognostic factors. While clinic stage and hormone receptors status might be referenced prognostic factors. ConclusionYoung women breast cancer patient may have good prognosis if multimodality treatment is conducted. Tumor size, axillary metastatic status, adjuvant endocrine therapy and overexpression of Her-2 are independent prognostic factors.

Objective To study bacteria-blocking effect of surgical gowns with new material.Methods Semi-quantitative and qualitative testing methods were used to detect bacteria-blocking rates of key sites of surgical gowns(chest and forearm), the detected samples included sample A (composite material, unused), sample B (composite material, after washing 100 times), and sample C (monolayer material, unused).Results In semi-quantitative testing,the average bacteria-blocking rates of three samples were 75.47%, 70.78%, and 73.73% respectively.In qualitative testing,three samples could effectively block the penetration of Staphylococcus aureus under wet condition and Bacillus subtilis var.niger spores under dry condition.Conclusion In semi-quantitative testing, all three kinds of samples had bacteria-blocking effect, and the average bacteria-blocking rate was> 70%;in qualitative testing, three samples all meet requirements of bacteria-blocking effect under wet and dry condition.

Objective To apply the optical coherence tomography(OCT) to detect the characteristics of coronary artery plaque and to investigate its correlation with levels of serum matrix metalloproteinase 7(MMP 7),MMP9 and MMP12.Methods The patients undergoing coronary arterial angiography for diagnosing coronary arterial lesions in the cardiology department of our hospital from October 2014 to March 2016 were collected and included into the research subjects.The subjects were divided into the stable plaque group and unstable plaque group based on the results of OCT scanning.The neovascularization characteristics such as the fibrous cap thickness of plaque,angle of lipid pool,macrophage infiltration and plaque cracks were detected by using OCT.ELISA was used to measure serum MMP7,MMP9 and MMP12 levels.Results (1) The fibrous cap thickness in the stable plaque group was more than that in the unstable plaque group(P＜0.01);the lipid pool angle,microphage infiltration,intima erosion and plaque cracks in the unstable plaque group were more than those in the stable plaque group(P＜0.05).(2) The MMP7 and MMP9 levels in the unstable plaque group were higher than those in the stable plaque group and control group(P＜0.05).(3) The fibrous cap thickness had significantly negative correlation with serum MMP9 level(r=-0.336,P=0.034);the MMP7 and MMP9 levels in the microphage infiltration group were higher than those in the non-microphage infiltration group(P＜0.05);the MMP9 level in the intima erosion group was higher than that in the non-intima erosion group(P＜0.01).Conclusion OCT can detect and find unstable plaque and the serum levels of MMP7 and MMP9 are significantly elevated in the patients with unstable plaque,which can be used as an important basis for predicting unstable plaque and guiding the treatment decisions.

BACKGROUND: There are many methods for the treatment of femoral head necrosis, such as core decompression, bone graft, arthroplasty and joint replacement, and each of which has its own shortcomings. So, percutaneous bal oon angioplasty combined with coral artificial bone provides a new attempt for the treatment of femoral head necrosis. OBJECTIVE: To observe the effect of percutaneous bal oon angioplasty combined with coral artificial bone on femoral head necrosis repair. METHODS: Twenty-four Duroc piglets were enrol ed to establish bilateral femoral head necrosis models by liquid nitrogen freezing method. Then, model piglets were randomly treated with percutaneous bal oon angioplasty combined with injectable coral artificial bone (experimental group) or bone cement (control group) on one affected side, and meanwhile, given no treatment on the contralateral side (blank control group). At 2, 4, 8 and 16 weeks after surgery, X-ray examination, biomechanical test and histological detection were conducted. RESULTS AND CONCLUSION: X-ray showed that at 16 weeks after surgery, numerous new bones could be found in the experimental group and there was a fuzzy boundary between the artificial bone and surrounding tissues; no new bone formed in the control group, and the boundary was clear; in the blank control group, the surface of the femoral head col apsed, and bone trabeculae arranged disorderly, which were seriously destroyed. And in the histological detection at 16 weeks after surgery, there were numerous bone trabecula and osteoblasts around the coral bone in the experimental group, and the coral artificial bone almost dissolved; in the control group, bone cement was in an irregular shape and no bone trabecula formed; in the blank control group, bone trabecula were damaged in the col apsed area, whose structure was in disorder. Additional y, biomechanical changes in the experimental group were significantly better than those in the other two groups at different time points after surgery (P < 0.05). In conclusion, percutaneous bal oon angioplasty combined with coral artificial bone can repair femoral head necrosis by promoting new bone formation.

Objective To investigate the perioperative hemodynamic features of mitral replacement of patients with small left ventricle.Methods Patients with left ventricle end-diastolic dimension (LVEDD) less than 40mm received mitral replacement sur- gery were divided into big size M-2 group and small size M-1 group.The perioperative echo results were analyzed with SPSS software. Results The big size M-2 group has lower trans mitral gradient [ (5.9?1.6) mm Hg vs.(10.7?3.2) mm Hg],larger in vivo va- lular acre[ (2.9?0.2) cm~2 vs.(2.6?0.2) cm~2],and high mitral match index [(1.92?0.23) cm~2/m~2 vs.(1.73?0.18) cm~2/m~2 ].Conclusion With the meticulous perioperative treatment and myocardial protection,the patients with small left ventricle should also receive a mitral replacement as big as possible to achieve the ideal hemodynamics results.

Objective:To evaluate the value of blood urea nitrogen (BUN)/creatinine (Cr) ratio for guiding the access route of double balloon enteroscopy (DBE) for small intestinal bleeding.Methods:The clinical information was collected from 105 patients who underwent DBE for suspected small intestinal bleeding at Air Force Medical Center from January 2015 to October 2019. Patients were divided into the elevated BUN/Cr group ( n=52) and the normal BUN/Cr group ( n=53), with a cut-off value of 81. Comparison was made for the detection rate of lesions between the oral route and anal route separately in the two groups using Chi-square test. Results:Among the 105 patients with suspected small intestinal bleeding, definite causes of bleeding were identified in 79 patients by DBE, and the overall lesion detection rate was 75.24% (79/105). In the elevated BUN/Cr group, the overall lesion detection rate was 76.92% (40/52), among which 79.49% (31/39) was through oral and 47.37% (9/19) through anal enteroscopy. In the normal BUN/Cr group, the overall lesion detection rate was 73.58% (39/53), and 63.64% (21/33) was transoral and 51.43% (18/35) transanal. The lesion detection rate of transoral enteroscopy in the elevated group was significantly higher than that in the normal group ( χ2=6.576, P=0.010). There was no significant difference in the lesion detection rate of transanal enteroscopy between the two groups ( χ2=2.230, P=0.135). Conclusion:For patients with active small intestinal bleeding (active bleeding within 48 hours), the BUN/Cr ratio higher than 81 may indicate that DBE should be performed firstly via oral route.

ObjectiveTo investigate the clinical characteristics and therapy of fresh cervical spinal cord injury without radiographic abnormality (SCIWORA) in children.MethodsThe materials of fourteen SCIWORA children (13 cases treated with non operative menthod, 1 case treated by atlantoocciptal fusion) were analyzed retrospectively.ResultsOne child was dead, and the other 13 cases had a 3-year follow up. Three children's symptoms had no change. According to ASIA criterion, there were 3 cases with grade A, 5 cases with grade B, 5 cases with grade C and 1 case with grade D before treatment. After treatment, there were 1 case recovered to grade B, 2 cases recovered to grade C, 5 cases recovered to grade D, 2 cases recovered to grade E.ConclusionSpinal cord injury caused by a short time dislocation of cervical vertebrae is the main reason of SCIWORA in children. The degree of the injury of spinal cord is related directly with the recovery of function of nervous system. Most patients can get satisfactory results by non operative methods. Operations are useful to the cases with obvious instability of cervical spine.

Objective To explore the risk factors for cesarean section after induction of late-term pregnancy. Methods This study enrolled 275 primiparas with a single cephalic fetal presentation,admitted to our hospital between December 2010 and December 2016 for induction of late-term pregnancy. After induction,80 underwent cesarean section and 195 had a normal vaginal delivery. Clinical data were collected and analyzed retrospectively. Single factor analysis and two categories of logistic regression analysis were used to determine the independent risk factors for cesarean section after induction of late-term pregnancy. Results Single factor analysis showed that the differences between the two groups in maternal height,cervical Bishop score before induction of labor,latent phase,intrapartum amniotomy,intrapartum oxytocin,meconium stained amniotic fluid,and birth weight were statistically significant (P < 0. 05). Multivariate analysis showed that maternal height,cervical Bishop score before induction of labor,and latent phase were independent risk factors for cesarean section after induction of late-term pregnancy. Conclusion Late-term pregnant primiparas with short stature,low Bishop score,or a long latent phase should have comprehensive prenatal maternal-fetal assessment,and a reasonable delivery mode should be chosen to avoid adverse outcomes.