Objective:To provide reference for clinical case diagnosis and treatment applications using descriptive analysis of patient-specific IgM and IgG test result of novel coronavirus pneumonia (COVID-19).Methods:Chemical luminescence was used to detect the levels of 423 confirmed or suspected cases IgM and IgG antibody, and the test result of patients with different clinical characteristics were compared and analyzed.Results:The positive rates of confirmed cases of COVID-19 were 80.4% (314/388) and 98.2% (381/388), for IgM and IgG respectively, and the positive rates of COVID-19 suspected cases specific IgM and IgG were 0.0% (0/24) and 45.8% (11/24), respectively. In patients at 6 weeks or more after the onset of the disease, the positive rate of IgG antibody was 100%. The level of IgG titer was generally higher in cases of 5~8 weeks after onset (mean: 112.70 AU/ml) than in cases of 1-4 weeks after onset (mean: 85.01 AU/ml) (U=8 531, P<0.0001). The level of IgG titer was higher in severe type cases than that of patients with ordinary type illness, with an average of 137.61 AU/ml. Conclusions:Specific IgM and IgG antibodies have strong application value in COVID-19 case diagnosis, and it is recommended to strengthen the tracking and monitoring of IgM and IgG titer levels in patients.

Objective:To investigate the clinical and pathological characteristics of breast cancer with HER2 low expression.Methods:The data from 3 422 patients with invasive breast cancer which archived in Peking Union Medical College Hospital between April 2019 and July 2022 were retrospectively reviewed. Among them, 136 patients were treated with neoadjuvant chemotherapy. The tumor size, histological type, tumor differentiation, lymph node metastasis, Ki-67 index, the status of estrogen receptor, progesterone receptor and HER2 as well as pathological complete response (pCR) rate were collected.Results:The HER2 status of 3 286 patients without neoadjuvant therapy, 616 (616/3 286, 18.7%) score 0, 1 047 (1 047/3 286, 31.9%) score 1+, 1 099 (1 099/3 286,33.4%) score 2+ and 524 (524/3 286,15.9%) score 3+ by immunohistochemistry (IHC). Among the 1 070 IHC 2+ cases, 161 were classified as HER2 positive by reflex fluorescence in situ hybridization (FISH) assay. In our cohort, 1 956 cases of HER2-low (IHC 1+ and IHC 2+/FISH-) breast cancer were identified. Compared to the HER2 IHC 0 group, HER2-low tumors more frequently occurred in patients with hormone receptor (HR) positive ( P<0.001), Ki-67 index below 35% ( P<0.001), well or moderate differentiation ( P<0.001) and over the age of 50 ( P=0.008). However, there were no significant differences in histological type, tumor size, and lymph node metastasis between HER2-low and HER2 IHC 0 group. For patients who had neoadjuvant therapy, the pCR rate in the patients with HER2-low was lower than those with HER2 IHC 0 (13.3%, 23.9%), but there was no significant difference. Although HER2-low breast cancers showed a slightly lower pCR rate than HER2 IHC 0 tumors, no remarkable difference was observed between tumors with HER2-low and HER2 IHC 0 regardless of hormone receptor status. Conclusions:The clinicopathological features of HER2-low breast cancers are different from those with HER2 IHC 0. It is necessary to accurately distinguish HER2-low breast cancer from HER2 IHC 0 and to reveal whether HER2-low tumor is a distinct biological entity.

With persistent breakthrough and maturity of surgical procedures and postoperative immunosuppressive therapy, the survival rate of liver transplant recipients and grafts has been significantly increased. The shortage of donor liver has become the main obstacle for clinical development of liver transplantation. How to expand the source of donor liver has become an urgent issue. Groundbreaking progresses have been made in the use of common marginal donor livers in clinical liver transplantation, such as elderly donor liver, steatosis donor liver, viral hepatitis donor liver and liver from donation after cardiac death. Nevertheless, multiple restrictions still exist regarding the use of marginal donor liver. Consequently, the definition of marginal donor liver and research progress in the application of common marginal donor livers were reviewed, and the opportunities and challenges of mariginal donoor liver were illustrated, aiming to provide reference for expanding the donor pool for clinical liver transplantation and bringing benefits to more patients with end-stage liver disease.