Aims To construct the N-terminal Strep-tagged ( NS-tagged) fusion protein expression vector, and to apply the vector to express NS-tagged fusion proteins of Chlamydia RNA polymerase subunit. Meth-ods By using PCR method, NS fusion protein tag and a new multiple cloning sites (MCS) were inserted into pET21c-DH plasmid by primers to replace the original T7 protein tag and MCS. The newly introduced Not I cutting site was chosen for self-ligation of PCR prod-uct. Then, the cyclized PCR product was transformed into DH-5α competent cells. The positive clones were selected by PCR and sequencing. To get NS-tagged fu-sion proteins of chlamydial RNA polymerase subunits, the α, β and β′ subunits were inserted between BamH I and Sal I cutting sites of the newly constructed ex-pression vector. Then, the NS-α, NS-β and NS-β′ ex-pression vectors were transformed into Arctic Express expression cells. The fusion protein expression statuses of transformed cells were identified by Commassie blue staining and Western blot. Results The NS-tagged fusion protein expression vector pET21c-NS-MCS was successfully constructed, and NS-α, NS-β and NS-β′fusion proteins were obtained by using this newly con-structed expression vector. Conclusions In this pro-ject, we constructed an NS-tagged fusion protein ex-pression vector and applied it to express NS-α, NS-βand NS-β′ fusion proteins. Our study can lay a solid foundation for the study of transcriptional regulation of Chlamydia genes.

Objective To investigate the feature of the microorganisms colonization of the thoracic catheter-related infection and evaluate the clinical significance of prophylactic antibiotics administration in patients with pneumothorax treated with closed thoracic drainage. Method A total of 120 patients with pneumothorax treated with closed thoracic dramage in emergency department wore enrolled. The patients were randomized (random number) into group A (n =60) and group B (n =60). In group A, the patients received levofloxacin mesylate injection and in group B, patients received physiological saline injection instead after closed thoracic drainage. The tip of catheter was cut off to get a 2-cm long segment after catheter removal and this segment was dipped into a bottle filled with liquid culture medium for microorganism culture. Statistical analysis carried out by using χ2 test or Fisher exact test. Results Of all 120 patients, microorganisms were found in 49 segments of catheter and 57 strains of microorganisms were found. The four most common microorganisms were Coagulase-negative staphylococci (57.9%), Candida albicans (10. 5%),Staphylococcus aureus (7%) and Acinetobacter baumanii (7%). All of them were highly drug-resistant to β-1actam antibiotics. The difference in the positive rate of microorganism culture was distinct in pneumothorax patients with underlying diseases (50%) in comparison to the patients without underlying diseases (31%) (P ＜ 0.05). The positive rate of microorganism culture increased significantly as the duration of drainage was longer than 14 days (P ＜ 0.01). The positive rate of culture in group A was lower than that in group B if the duration of drainage was less than 7 days (8.3% vs 52.9%, P ＜ 0.01). The positive rate of culture after drainage for 7 days was 21.4% in group A and 68.8% in group B (P ＜0.05), and that after drainage for over 14 days was 70% in both groups (P ＞ 0.05). There were no significant differences in outcome and days of hospital stay between two groups (P ＞ 0. 05). Conclusions The common colonized microorganisms of thoracic catheter-related infection are conditional pathogens and highly resistant to antibiotics. Lengthening the duration of drainage and having underlying diseases increase the risk of infection. Although prophylactic antibiotics administration is beneficial to decrease the risk of thoracic catheter-related infection, it has no effects on shortening hospital stay and outcome of disease.

ObjectiveTo determine the effectiveness of endovascular embolization in patients with cryptogenic massive hemoptysis who were all long-term smokers.Methods Aortography and subclavian artery angiography were performed in 21long-term smokers with cryptogenicmassive hemoptysis.Transarterial embolization (TAE) was performed in patients with detectable pathologic systemic arteries.The angiographic findings were reviewed and the clinical and follow-up CT results were observed.ResultsThe pathologic systemic arteries were all bronchial arteries (BAs) and thirty-five arteries were involved.The angiography demonstrated peripheral hyperplasia in all BAs,with 24 pathologic BAs supplying the right lung and 25 supplying the upper lobes.In thirty-five BAs,24 showed hypertrophy and 11 were normal.TAE of the pathologic BAs was successfully performed and cessation of bleeding was achieved in all patients.During follow-up,one patient had episodic bloody sputum after embolization and no recurrence in all patients.The follow-up CTdemonstratednoadditionalabnormalitybesidespre-existingpulmonaryemphysema.Conclusion Cryptogenic massive hemoptysis in long-term smokers efficiently treated by endovascular embolization of the responsible bronchial artery.

OBJECTIVETo investigate the effects of all-trans retinoic acid (atRA) on the function of bone morphogenetic protein receptor 2 (BMPR2) expression in embryonic palate.

METHODSCleft palate mice model was established by atRA. On gestation day (GD) 15 and GD 17, the pregnant mice were killed to obtain the embryos from the uteri. The embryonic palates were stained with hematoxylin-eosin, and the remaining sections were used for the immunohistochemistry of BMPR2 detection. Reverse transcription-polymerase chain reaction was performed to detect the expression levels of Bmpr2 mRNA.

RESULTSIn the atRA-treated group, short extensions and failure to fuse with each other were observed. The positive expression of BMPR2 was detected in developing palatal process from GD 15 to GD 17 in the control group. Compared with those of the control group, BMPR2 protein and Bmpr2 mRNA decreased in the atRA-treated group (P<0.05).

CONCLUSIONThe treatment of pregnant mice with retinoic acid produces small palatal shelves in their fetuses and down-regulates BMPR2 expressions.

Animals ; Bone Morphogenetic Protein 2 ; Cleft Palate ; Disease Models, Animal ; Down-Regulation ; Female ; Mice ; Pregnancy ; RNA, Messenger ; Tretinoin

[Objective] To investigate the clinical value of using prospective ECG-gating Helical protocol in whole aorta and coronary arteries CT angiography combined with low tube voltage,low contrast medium injection rate and dose technology.[Methods]A total of 60 patients (heart rate≤ 75 bpm and normal heart rhythm) with suspected aortic disease or post-operation were randomly divided into 2 groups:G1 (n =30;tube voltage:80 kV;contrast medium injection rate:3 mL/s;contrast medium dose:0.65 mL/kg)and G2 (n =30;tube voltage:120 kV;contrast medium injection rate:4 mL/s;contrast medium dose:1.2 mL/kg).The two groups underwent aorta angiography with prospective ECG-gating Helical protocol by using 320-detector CT.The mean CT values and standard deviation of aorta,coronaries and adjacent adipose tissue were measured,signal to noise ratio (signal-to-noise ratio,SNR)and contrast to noise ratio (contrast-to-noise ratio,CNR) were calculated.The subjective quality scoring of 3-d post-processing images were evaluated independently by 2 senior radiologists.The mean CT values and standard deviation of aorta,coronaries and adipose tissue,SNR,CNR,subjective quality scoring,contrast medium dose and radiation dose were compared and analyzed.[Results] The abnormal and normal rate of aorta in two groups were 83.33％ (25/30),16.67％ (5/30) and 86.67％ (26/30),13.33％(4/30);while the abnormal and normal rate of coronary arteries in two groups were 43.33％ (13/30),56.67％ (17/30) and 53.33％(16/30),46.67％ (14/30).SNR values of ascending aorta,descending aorta,abdominal aorta,superior mesenteric artery,bilateral renal artery,left main coronary artery,left anterior descending branch,left circumflex branch,right coronary artery and CNR values of abdominal aorta,superior mesenteric artery,bilateral renal artery,left anterior descending branch,left circumflex branch had no statistical significance,while the other indicators were significant differences between the two groups.The radiation dose and the contrast medium dose of G1 was significantly lower than G2 (P ＜ 0.05).There was no difference in the subjective image quality of 3D post-processing images between the two groups (P ＞ 0.05).[Conclusions] Using prospective ECG-gating Helical protocol in whole aorta and coronary arteries CT angiography combined with low tube voltage,low contrast medium injection rate and low contrast medium dose technology can help to reduce radiation and contrast medium dose without impacting on the imaging quality satisfactorily.

[Objective] To observe the effect of computer-aided detection (CAD) system in improving lung nodule detection sensitivity and inter-observer variation.[Methods] 300 PA digital radiographs including 100 normal cases and 200 cases with pulmonary nodules confirmed by CT were enrolled.Two senior chest radiologists referenced CT images and marked the sizes and locations of all nodules with consensus as the gold standards.Four senior radiologists and four junior radiologists interpreted the digital chest radiographs independently without and with CADand recordtheir results.Pair t test and coefficient of variation (CV) was used to compare the difference of lung nodule detection sensitivity and inter-observer variation between withoutand with CAD.[Results] The mean lung nodule detection sensitivity of senior and junior radiologists withoutand with CAD were (41.1 ± 2.0)％,(28.0 ± 2.0)％ and (45.0 ± 1.8)％,(39.2 ± 0.9)％,respectively,statistical analysis showed there was statistically significant difference.Moreover,CV of all radiologists without and with CAD were 20.9％ and 8.1％.[Conclusion] Both lung nodule detection sensitivity and inter-observer variation of senior and junior radiologists can be improved by CAD.

According to the course teaching requirements of psychiatry,a serial teaching cases of case-based learning (CBL) is built based on cases from psychology department to assist in the theory teaching of Psychiatry.During the teaching process,the scenes where patients came to the psychology department were simulated and the information about the cases was provided step by step.For each step,students would be asked to discuss a series of questions regarding the cases in different groups.Along with CBL,students could thoroughly learn the main points of diagnosis and principles of treatment for common psychiatric disorders.The teaching effect showed that students' involvement in CBL courses,the interests in learning,self-study ability,independent thinking ability,capacity for self-expression,ability of creative thinking and comprehensive analysis and problem solving ability.were greatly improved.Most students were interested in CBL and it produced fruitful teaching results.