Aim To establish a mouse breast cancer model stab-ly expressing HER2. Methods 4T1-Luc mouse breast cancer cell line was transfected with the full-length human HER2 gene and selected with G418. The HER2 expression in 4T1-Luc stable cells was detected by fluorescence-activated cell sorting ( FACS) and Western blot. 4T1-Luc/HER2 cells were implanted into the mammary fat pads of BALB/c or nude mice. After tumor stabili-zation, mice were randomly assigned into 4 groups for treatment with PBS control, chA21, Trastuzumab, or chA21 plus Trastu-zumab. Tumor volumes were measured and tumor growth inhibi-tion ratios were calculated twice a week. At the end of experi-ment, tumor metastasis in mice was detected by bioluminescence imaging technology. Results Several 4T1-Luc/HER2 stable cell clones were obtained after G418 selection. FACS and West-ern blot analysis showed that all clones expressed HER2 protein at high levels. These 4T1-Luc/HER2 clones showed good tumor-igenicity in mice with steady tumor growth after one week of cell implantation. After 2-3 weeks, metastatic tumor cells were seen in the lung, cheek and groin areas. In BALB/c mice, the tumor growth inhibition ratio was 43. 3% in chA21 plus Trastuzumab group (P<0. 05 vs PBS control), which was higher than chA21 group (11. 1%) or Trastuzumab group (23%). In addition, the luminescence number and density of tumor metastases in lungs were significantly reduced in the antibody combination group. Conclusions The mouse model of spontaneously metastasizing breast cancer with HER2 overexpression is successfully estab-lished. The preliminary study suggests that anti-HER2 antibody combination of chA21 and Trastuzumab has excellent inhibitory effects on tumor growth and metastasis.

Objective: To explore the application of real-time three-dimensional ultrasound in locating the course, the brand and the blind end of internal opening of congenital preauricular fistula. Methods: Congenital preauricular fistula patients from Changhai Hospital were studied. All the cases were evaluated using two-dimensional and three-dimensional ultrasound before surgeries. The surgery findings were utilized as the gold standard. The imaging features of 3D ultrasound were described to determine the accuracy of the blind end location, the course of the main fistula tract and the branch tracts. The diagnosis was compared with the surgery findings. Results: In 89 cases, among which there were 21 branch fistulae. There were 68 bend fistulae without branch. The diagnostic accuracy of both two-dimensional ultrasound and three-dimensional ultrasound was 100%. The accuracy in locating the blind end of internal opening, the course of the branch tracts with 3D ultrasound was 92.1%(82/89), 85.7%(18/21) , compared to 80.9%(72/89), 57.1%(12/21) with 2D ultrasound. It was obvious that 3D ultrasound had more advantages. These differences were statistically significant (χ²=4.8, P<0.05; χ²=4.2, P<0.05). Conclusions Compared with 2D ultrasound, 3D ultrasound can accurately locate the blind end of internal opening, the course, and the branch of preauricular fistula, clearly display the morphology and the spatial structure of preauricular fistulaand its surroundings. It has high clinical application value in preoperative imaging examination.

In the emergency of the outbreak of COVID-19 in December 2019, Shaanxi Provincial Health Committee mobilized several medical teams from major hospitals in the province, and, by relying on Xi’an Chest Hospital, jointly established an anti COVID-19 consortium to control and eradicate the epidemic in a short time. Information support is an important guarantee for winning this battle. In order to realize the efficient cooperation among multiple medical teams, we have carried out some exploratory and innovative information support services on the basis of the original information system of the chest hospital. In this process, we have gone through some detours. Some compromises were made on some problems that could not be solved in the short term. Finally, in an environment full of uncertainty, a set of information support management system with basically smooth operation was built through rapid trial and error adjustment. The system mainly includes the following aspects: support of the organizational structure and operation process of the anti-epidemic consortium, support for medical collaboration related businesses of multiple medical teams, and support for statistical reports and online meetings. Information support has played a very important role in this action, and this practice has also accumulated experience for us to deal with similar situations in the future.