Objective To discuss the characteristics and management of pregnancy on cesarean section scar. Methods Five women with pregnancy on cesarean section scar were reviewed from Apr. 2000 to Mar. 2003. Results All of the five patients had cesarean section before and suffered from painless,irregular vaginal bleeding after 6～8 weeks of amenorrhea. The pregnancy could be misdiagnosed as invasive mole or cervical pregnancy. All had better outcome by uterine suction under ultrasound monitoring without massive bleeding or hysterectomy. Conclusions Women who had cesarean section before are in the risk of pregnancy on the old scar. Clear diagnosis should be made before any treatment. Ultrasound monitoring,local MTX injection and packing can be utilized to prevent perforation during suction. Patients should be monitored continuously after operation with serum hCG level and ultrasound. The principle prevention of pregnancy on cesarean section scar is to reduce the cesarean section rate and effective contraception.

Objective To explore the operational indications, preoperative evaluation,operative essentials and clinical prospect of endovascular repair(EVR) for aortic dissection.Methods Twenty-six patients underwent EVR for aortic dissection and all cases were Stanford B dissection.Four patients had two or more tear entries in different sites.Computed tomography angiography(CTA) or digital subtraction angiography(DSA) were used as preoperative evaluation methods.Results The grafts were installed successfully in 26 patients(100%).The patients were followed up for 1 to 18 months after treatment,and there was no endoleaks and organ or limb ischemia in all the patients.Conclusion Endovascular repair was simple,safe and effective in treating aortic dissection and dissecting aneurysm.

Objective To detect whether there is neurotropism following end-to-side neurorrhaphy by means of the neuron retrograde tracing technique. Methods Forty female Sprague-Dawley rats were randomly divided into 4 groups: tracing main branch of musculcutaneous nerve(MC) of end-to-side group, tracing MC main branch of normal group, tracing MC motor branch of end-to-side group and tracing MC motor branch of normal group.In two end-to-side groups, the MC was transeeted, then an 1 mm epineukral window was created on the ulnar nerve. Distal end of MC nerve was sutured to the windowed ulnar nerve by means of end-to-side neurorrhaphy.In two normal control groups, MC and ulnar nerves were just exposed. Five months post operation, by means of retrograde Fluoro-Gold neuron tracing technique,the number of C5～ T1 anterior horn motoneurons and dorsal root ganglion sensory neurons of all groups were counted. Results In two tracing MC main branch groups: the motor neuron counts in end-to-side group was 245.2 ± 93.8, the motor neuron counts in normal group was 846.7 ± 264.8, and counts of end-to-side group was 30.0% of the normal control group (P＜ 0.01). The sensory neuron counts in end-to-side was 434.7 ± 160.4, the sensory neuron counts in normal group was 1545.2 ± 287.4, and counts of end-to-side group was 28.1% of the normal control group (P ＜ 0.01). The per-centage of motor neuron in end-to-side group was 0.36 ± 0.09, there was no difference between end-to-side group and normal control group(P＞ 0.05). In two tracing MC motor branch groups: the motor neuron counts in end-to-side group was 72.3 ± 35.3, the motor neuron counts in normal group was 189.7 ± 57.0, and counts of end-to-side group was 38.1% of the normal control group (P ＜ 0.01). The sensory neuron counts in end-to-side was 110.8 ± 52.5, the sensory neuron counts in normal group was 157.9 ± 50.0, and counts of end-to-side group was 70.2% of the normal control group (P ＞ 0.05). The percentage of motor neuron in end-to-side group was 0.40 ± 0.14, the difference between end-to-side group and normal control group was signifieant(P ＜ 0.01 ). Conclusion Neurotropism in collateral spouting after end-to-side neurorrhaphy is not significant.

OBJECTIVETo explore the effects of trichloroethylene (TCE) on cardiac developmental differentiation in human embryonic stem cells.

METHODSIn this study, based on the human embryonic stem cells in vitro cardiac differentiation assay, we investigated the potential effect of TCE exposure on the cardiac toxicity in embryo development. Human embryonic stem cells were treated with TCE at different concentrations of 100 ppb, 1 ppm, and 10 ppm and dimethyl sulfoxide(DMSO) treated as control. The MTT assay was performed to examine the cytoplasmic toxicity of TCE exposure. The beating percentages were recorded and the expression of cardiac specific gene was evaluated by PCR or flow cytometry. Also, real time PCR was performed to verify the micro array analysis on the expression level changes of genes which were involved in the Ca2+ signal pathways.

RESULTSCompared with the control group, there was no significant difference in cell viability when cells were treated with TCE at the concentrations of 100 ppb, 1 ppm, and 10 ppm. However, TCE could inhibit the expression of cTnT protein in a concentration-dependant manner. And the most interestingly, TCE significantly inhibited the cardiac differentiation characterized by the decrease beating percentages. Genes involved in Ca2+ signaling pathway were severely disrupted by TCE.

CONCLUSIONTCE inhibited the cardiac specific differentiation of human embryonic stem cell and at the meanwhile the genes responsible for Ca2+ signaling pathway were severely disrupted, which could contribute the severe effects of TCE cardiotoxicity.

Calcium Signaling ; Cell Differentiation ; Cells, Cultured ; Embryonic Development ; Embryonic Stem Cells ; cytology ; drug effects ; Heart ; embryology ; Humans ; Trichloroethylene ; toxicity

AIM:To construct eukaryotic expression vector of Sirt2 and detect its expression in HEK293 cells. METHODS: Total RNA was isolated from brain tissue of a-dult SD rat. A 1 130 bp fragment containing the coding region of Sirt2 was amplified by RT-PCR and the resulting PCR product was subcloned into PMD20-T vector and se-quenced. Coding region of Sirt2 was generated with PCR by using the PMD20-T-Sirt2 as template, the amplified PCR fragment was inserted into the EcoR I and Hind Ⅲ sites of the pcDNA3. 1myc-his(-)A expression vector, and the sequence was confirmed by DNA sequencing. The expression of new construct pcDNA3.1 myc-his(-) A-Sirt2 in HEK293 cells was detected by immunofluorescence. RESULTS: The full length coding region of Sirt2 was obtained and confirmed by sequencing, the expression of Sirt2 was detected successfully in HEK293 cells. CONCLUSION: The eukaryotic expression vector of Sirt2 has been successfully constructed, which will provide a useful tool for designing an in-depth investigation of the role of Sirt2.

According to the theory of microscopic system reform in higher education, a total of 927 college students of different majors from Beijing University of Chinese Medicine were investigated by using SIMPP method. It indicated that through promoting the study of self-prepared, learning state and learning effect, students can enhance their learning ability of the admission acceptance. From the perspective of teachers, the students' self-study ability can be fully mobilized using individual person-alized teaching method. Then, the initiative of university education in the teaching and learning can be improved. Ultimately, the efficiency of student learning can be improved.

Interest in learning can not only stimulate students' enthusiasm for learning, but also directly affect the quality of higher education. In this paper, the questionnaire of the related factors of college students' interest was designed to carry out micro-system engineering research. The factors as-sociated with college students' interest in learning and their complex relationships were investigated by using methods of systems science and systems engineering. The results shows that the students who can actively participate in after-school learning discussions , feel good in lectures and have clear learning objectives, are interested in learning. And at the same time, the teacher's influence and his active guidance in classroom teaching will raise students' interest in learning. This study provides a more comprehensive basis and clues to improve students' interest in learning and education reform.

Objective To detect the mutation of STK11 in a family with Peutz-Jeghers syndrome.Methods Genomic DNA was extracted from peripheral blood and harmatoma polypus of all the patients,and 9 exons and noncoding regions of STK11 were amplified by PCR.Cycle sequencing was used to analysis the DNA sequence,and western blot was used to detected the mutational STK11 protein in the harmatoma polypus.Results The 21th codon CAG in exon 5 of STK11 gene transformed to TAG in all the patients,which translated into a truncated STK11 protein.Conclusion This novel mutation is the pathogeny of PJS in this family,which could be an indicator for the diagnosis of PJS in this family.And it may lead to a higher risk of cancer in patients.

Objective To evaluate the effcacy and safety of nephron-sparing surgery(NSS) in the treatment of renal angiomyolipoma(AML) in middle-aged and elderly patients.Methods From September 2002 to September 2011,NSS was performed in 12 cases with renal AML in our hospital.Renal function was observed before and after surgery.Tumor size,pathological findings,surgical complications and prognosis were retrospectively analyzed.Clinical features were summarized.Results The age of patients ranged from 45 to 65 years(median 60.2 years).There were 2 males and 10 females in this study,including 1 eases with solitary kidney.Open NSS were performed in 2 cases and laparoscopic surgery in 10 cases.Tumor diameter was(6.8 ±3.3) cm on average,ranged from 3.5 cm to 12.0 cm.Intraoperative findings showed that diameters of AML in the basal kidney were small,similar to themushroom in shape,and the depth of tumor invasion into the renal parenchyma was superficial.Pathologic results showed that pathologically classic AML was found in 9 cases,epithelial-like type in 2 cases,leiomyoma type in 1 case.Mean intraoperative blood loss was 250 ml(100-750 ml).Postoperative retroperitoneal hematoma occurred in 1 case.Serum creatinine level showed no statistically significant difference between pre-surgery and 10 days after surgery [(87 ±34) mmol/L vs.(92±37) mmol/L,t=2.073,P＞0.05].During mean follow-up of 26.5 months (12-48 months),no renal insufficiency was found.Conclusions NSS is an effective and safe treatment for renal AML in middle-aged and elderly patients.

BACKGROUND: Quiet a number of researches has reported the morphological changes of global ischemic reperfusion model. However, there are few reports on the ultrastructural changes of cortex in early reperfusion, especially the change of blood brain barrier.OBJECTIVE: To explore the changes of brain cortex neurons, glial cells and blood brain barrier in order to provide reliable evidence for clinical treatment.DESIGN: A randomized and controlled trial.SETTING: Department of Neurosurgery, Departnent of Anesthesia and Electron Microscope Room of Beijing Tiantan Hospital.MATERIALS: The experiment was conducted to 6 Wistar rats in Beijing Neurological Surgery Research Institute of Capital University of Medical Sciences during February 2003 to February 2004. The rats were randomly divided into two groups with one of ischemia-reperfusion group and sham operation group with 3 rats in each group.INTERVENTIONS: To prepare global ischemic reperfusion model of rats. Brain was removed from ischemic group in one hour of reperfusion and from sham operation group one hour after the operation. Electronic microscope technique was used to observe the ultrastructural changes of cortex.MAIN OUTCOME MEASURES: Ultrastructural changes of cortex.RESULTS: The neurons of cortex shrank to certain degree in the early stage of ischemic reperfusion(1 hour) . The glial cells were swollen with dissolved chromosome in nucleus and unclear nuclear membrane. The foot protrusions around blood vessel slightly swelled and separated from basement membrane. Mircro-tubes were partially dissolved.CONCLUSION: In early stage of reperfusion injury, the cortex neurons, glial cells, cellular framework and blood brain barrier already changed which suggested that the protective treatment such as reducing brain edema, protecting blood brain barrier should start as early as possible.