Chromosomally encoded toxin–antitoxin (TA) systems are thought to result in growth arrest and eventual cell death upon exposure to environmental stress in E. coli. In the chromosome of cyanobacteria Synechocystis sp. PCC6803, the genetic organization of a 360 bp open reading frame (ORF), slr0664, and another small ORF of 256 bp, ssr1114, is similar to that of TA system. The predicted protein encoded by slr0664 is homologous to RelE, but neither homologue of ssr1114 nor ssr1114-encoding protein was found in TA system. To see whether slr0664 encodes a toxin protein, ssr1114 encodes an antitoxin, an expressing plasmid containing promoter Plac and PBAD, was constructed. In this construct, Both slr0664 and ssr1114 were controlled by Plac and PBAD, respectively. Expression of slr0664 in Escherichia coli results in the inhi-bition of bacterial growth, the expression of ssr1114 neutralize the toxicity of slr0664 expression. These re-sults show that slr0664 is toxin gene and ssr1114 is antitoxin gene, both ssr1114 and slr0664 constitute achromosomal TA system in Synechocystis sp. PCC6803.

Objective To investigate the efficacy,side effects and cosmetic effects of breast-conserving operation combined with radiotherapy for patients with breast cancer. Methods Forty-three patients with early stage of breast cancer(n=30 for stage I and n=13 for stage II) were performed extended resection plus axillary lymph node dissection or quadrant resection plus axillary lymph node dissection.After operation,tangential field irradiation was conducted with 50 Gy of X ray,tumor bed was irradiated with additional 10 Gy of electron beam,and supraclavicular field irradiation was also administered with 30 Gy of X ray and 22 Gy of electron beam. Results There was no recurrence during the follow up for 14 to 50 months.The acute side effects of radiotherapy included breast complaints(n=10,grade Ⅰ,23.26%),skin erythema and hyperpigmentation(n=19,grade Ⅰ,44.19%),moist desquamation(n=5,grade Ⅱ,11.63%) and radiation esophagitis(n=4,grade Ⅰ,9.30%),while one patient experienced radiation esophagitis one month after radiotherapy.No such complications as skin fibrosis and necrosis,angiotelectasis,breast and upper extremity edema occurred.The short-term cosmetic effects were satisfactory to 93.02% of all the patients. Conclusion For early stage of breast cancer(stage I and stage Ⅱ),breast-conserving operation combined with radiotherapy may yield satisfactory survival rate and short-term cosmetic effects,as well as low incidences of side effects.

Mesenchymal stem cells(MSCs)is a kind of non hematopoietic stem cell from the mesoderm, which can self renew, proliferate and perform multilineage differentiation. Due to the characteristics of acquiring easily and low immunogenicity, it has become the main cell for myocardial infarction. In this article, the biology and the immunology of the MSCs is reviewed, the safety and the validity of the therapy on myocardial infarction with MSCs and the HGF/MSCs is introduced. And furthermore, it also explains the possible mechanism and the problems of how to improve the cardial function.
Cell Differentiation ; Hematopoietic Stem Cells ; Humans ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; Myocardial Infarction ; therapy

Objective To prepare the “bacterial ghost” of E.coli with heat-induction and analyse its lysis rate and configuration. Methods Through immediately shifting the culture temperature from 37℃ to 42℃, E.coli DH5? including plasmid pMuH36 was induced to lyse, and the OD value of culture media was measured every 30 minutes during the induction. After 4 hours of induction, the bacteria samples were collected to examine the lysis rate by CFU (colony formation unit) and the configuration of lysed bacteria was observed by transmission electron microscopy (TEM). Results The OD value of DH5? (pMuH36)began to decline after 1 hour of induction, and increased slowly after 4 hours of induction. The CFU assay showed that the lysis rate was about 95%. TEM observation proved that most of the lysed bacteria were emptied, whereas the whole outmembrane structure, i.e. “bacterial ghost”, remained. Conclusions The E.coli “bacterial ghost” was efficiently prepared and identified, which might provide the basis for further development of a more effective “bacterial ghost” vaccine and adjuvant.

Objective To investigate freshmen's prevalence of depression disorder and to analyse the in-fluential factors on depression in military colleges. Methods Depression, self-consciousness, coping style, per-sonality feature, birth background and other factors were investigated by MMPI and related questionnaires in 683 freshmen of military colleges. Results The prevalence of depression disorder was 3.66% ; $i, Dy, Ne mean scores of freshmen with depression disorder were significantly higher than without depression disorder(t= 5. 348,3. 879,2. 997 ) (P<0.05, P<0.01)), otherwise, Do, Pc , PEI ones were significantly lower than without depres-sion disorder( t= -2.171, -2.602, -2.62) (P<0.05, P<0.01);D mean score of all subjects was significant-ly related to Si, Dy, Do, Nc, PEI,Pe(r=0.600,0.465, -0.356,0. 240, -0. 353, -0. 146) (P<0.05, P<0.01 ). And also Si,Do,Pc,Nc got into regression quotation. Condusion Freshmen's depression is associated with their personalities,coping style and self-consciousness, however,their personalities, coping style were most important pre-dictors.

Future competition in the medical market will in essence be the contest of the core competitiveness of hospitals.It is therefore imperative for hospitals to do a good job in the following aspects in light of trends in medical development,the state of its resources and the needs of the market: enhancing their awareness of the importance of scientific and technological work,setting up a rationally distributed scientific research system,strengthening personnel and disciplinary development,improving the quality of scientific and technological management personnel,and establishing standardized systems for scientific and technological management.The goal is to enhance core competitiveness so as to gain competitive edges for sustainable development.

Objective To explore the extent of lymphadenectomy by comparing the single left thoracotomy and cervico-right thoracic-abdominal triple incision during esophageal carcinoma radial surgery.Methods The clinical data of 95 patients with thoracic esophageal carcinoma underwent esophagectomy plus lymphadenectomy were studied.They were divided into two groups,left thoracotomy group(62 cases)and triple incision group(33 cases).The rates of lymph node metastasis and postoperative complications were analyzed statistically.Results A total of 1322 lymph nodes were dissected with an average of 13.9 lymph nodes in each case.The rates of lymph node metastasis were 45.3 ％(43/95)of all patients,40.3 ％ of left thoracotomy and 54.5 ％ of triple incision.The rates of lymph node metastasis in the neck for patients with upper or middle thoracic esophageal carcinoma were 25.0 ％(2/8)and 40.0 ％(4/10).The rate of abdominal lymph node metastasis was 53.8 ％(7/13)in lower thoracic carcinoma.The depth of tumor invasion (r =0.315,P =0.007)and tumor differentiation(r =0.239,P =0.017)were correlated to lymph node metastasis.Patients with tumor length ＞2 cm had higher rates of lymph node metastasis(x2 =34.2,P ＜ 0.001).The postoperative complication rates of left thoracotomy and triple incision were 25.8 ％(16/62)and 4.2 ％ (8/33).The mortalities rates of left thoracotomy and triple incision were 1.6 ％(1/62)and 3.0 ％(1/33).There was no significant difference in postoperative complication rates(x2 =0.017,P =0.869)and mortalities rates(x2 =0.047,P =0.651)between the two groups.Conclusion Tumor invasion,differentiation and length should be incorporated in the evaluation of lymph node status.Patients with upper and middle thoracic esophageal carcinoma should receive cervico-right thoracic-abdominal triple incision.Particular attention should be given to the resection of abdominal lymph nodes in patients with lower thoracic esophageal carcinoma.

The development of the imaging technology enables diagnostic methods of detect intracranial aneurysms diversified. In recent years, the diagnosis of aneurysms was confirmed by digital subtraction angiography (DSA) which was regarded as the "gold standards". However, CT angiography (CTA), which appears as a fast, non-invasive, and easily achievable examination, is becoming as a new option in clinic. With the development of the CT facility and upgrade of the workstation software, CTA is more widely used in both diagnosing and treating intracranial aneurysm. This article reviews the sensitivity and specificity of CTA in the detection of intracranial aneurysms, and systematically analyzes its advantages and disadvantages as well as its development, imaging methods.

OBJECTIVEThe aim of this study was to determine the accuracy of personalized implant fabricated via 3D printing and fused deposition modeling technique (FDM) and to compare the results with a real tooth.

METHODSSix prepared extracted orthodontic teeth (in vivo) were scanned via cone beam computed tomography (CBCT) to obtain 3D data and to build the data models by using Mimics 15.0 software. The extracted orthodontic teeth (in vitro) and the personalized implants designed via 3D printing and FDM were scanned via CBCT to obtain data and to build the data models at the same parameters. The 3D deviations were compared among the in vivo teeth data models, in vitro teeth data models, and printing personalized implant data models by using the Geomagic studio software.

RESULTSThe average deviations of high and low areas between date models of in vivo teeth and personalized implants were 0.19 mm and -0.16 mm, respectively, and the average deviations between in vitro and in vivo teeth were 0.14 mm and -0.07 mm, respectively. The independent t test showed that no statistically significant difference was observed between the two groups (P>0.05).

CONCLUSION1) The personalized dental implants were manufactured via 3D printing and FDM with a high degree of precision. 2) Errors between the data models of in vitro and in vivo teeth were observed at the same CBCT parameters.

Objective: To study the change of placental corticotropin releasing hormone level in pregnant women entering spontaneous labor at term and preterm or posterm,and to investigate the value of CRH as an indicator of preterm labor. Methods: Subjects( n =200) were recruited to the study at their antenatal visits,and plasma samples were obtained at their routine antental clinic visits from 28 weeks to parturition at 2 weeks intervals.CRH were measured by radioimmunoassay. Results: CRH concentrations rose significantly as pregnancy developed and reached the highest level at delivery. Plasma CRH levels were significantly higher in preterm labor and lower in postterm labor after gestational 28 weeks( P