Objective:In general, patients with seropositive rheumatoid arthritis (RA) are considered to show an aggressive disease course. However, the relationship between the two subgroups in disease severity is controversial. Our study is aimed to compare the clinical characteristics and prognosis of double-seropositive and seronegative RA in China through a real-world large scale study.Methods:RA patients who met the 1987 American College of Rheumatology (ACR) classification criteria or the 2010 ACR/European Anti-Rheumatism Alliance RA classification criteria, and who attended the 10 hospitals across the country from September 2015 to January 2020, were enrolled. According to the serological status, patients were divided into 4 subgroups [rheumatoid factor (RF)(-) anti-cyclic citrullinated peptide (CCP) antibody (-), RF(+), RF(+) anti-CCP antibody(+), anti-CCP antibody(+)] and compared the disease characteristics and treatment response. One-way analysis of variance was used for measurement data that conformed to normal distribution, Kruskal-Wallis H test was used for measurement data that did not conform to normal distribution; paired t test was used for comparison before and after treatment within the group if the data was normally distributed else paired rank sum test was used; χ2 test was used for count data. Results:① A total of 2 461 patients were included, including 1 813 RF(+) anti-CCP antibody(+) patients (73.67%), 129 RF(+) patients (5.24%), 245 RF(-) anti-CCP antibody(-) patients (9.96%), 74 anti-CCP antibody(+) patients (11.13%). ② Regardless of the CCP status, RF(+) patients had an early age of onset [RF(-) anti-CCP antibody(-) (51±14) years old, anti-CCP antibody(+) (50±15) years old, RF(+) anti-CCP antibody(+) (48±14) years old, RF(+)(48±13) years old, F=3.003, P=0.029], longer disease duration [RF(-) anti-CCP antibody(-) 50 (20, 126) months, anti-CCP antibody(+) 60(24, 150) months, RF(+) anti-CCP antibody(+) 89(35, 179) months, RF(+) 83(25, 160) months, H=22.001, P<0.01], more joint swelling counts (SJC) [RF(-) anti-CCP antibody(-) 2(0, 6), Anti-CCP antibody(+) 2(0, 5), RF(+) anti-CCP antibody(+) 2(0, 7), RF(+) 2(0, 6), H=8.939, P=0.03] and tender joint counts (TJC) [RF(-) anti-CCP antibody(-) 3(0, 8), anti-CCP antibody(+) 2(0, 6), RF(+) anti-CCP antibody(+) 3(1, 9), RF(+) 2(0, 8), H=11.341, P=0.01] and the morning stiff time was longer [RF(-) anti-CCP antibody(-) 30(0, 60) min, anti-CCP antibody(+) 20(0, 60) min, RF(+) anti-CCP antibody(+) 30(10, 60) min, RF(+) 30(10, 60) min, H=13.32, P<0.01]; ESR [RF(-) anti-CCP antibody(-) 17(9, 38) mm/1 h, anti-CCP antibody(+) 20(10, 35) mm/1 h, RF(+) anti-CCP antibody(+) 26(14, 45) mm/1 h, RF(+) 28(14, 50) mm/1 h, H=37.084, P<0.01] and CRP [RF(-) anti-CCP antibody(-) 2.3 (0.8, 15.9) mm/L, Anti-CCP antibody(+) 2.7(0.7, 12.1) mm/L, RF(+) anti-CCP antibody(+) 5.2(1.3, 17.2) mm/L, RF (+) 5.2(0.9, 16.2) mm/L, H=22.141, P<0.01] of the RF(+)patients were significantly higher than RF(-) patients, and RF(+) patients had higher disease severity(DAS28-ESR) [RF(-) anti-CCP antibody(-) (4.0±1.8), anti-CCP antibody(+) (3.8±1.6), RF(+) anti-CCP antibody(+) (4.3±1.8), RF(+) (4.1±1.7), F=7.269, P<0.01]. ③ The RF(+) anti-CCP antibody(+) patients were divided into 4 subgroups, and it was found that RF-H anti-CCP antibody-L patients had higher disease severity [RF-H anti-CCP antibody-H 4.3(2.9, 5.6), RF-L anti-CCP antibody-L 4.5(3.0, 5.7), RF-H anti-CCP antibody-L 4.9(3.1, 6.2), RF-L anti-CCP antibody-H 2.8(1.8, 3.9), H=20.374, P<0.01]. ④ After 3-month follow up, the clinical characteristics of the four groups were improved, but there was no significant difference in the improvement of the four groups, indicating that the RF and anti-CCP antibody status did not affect the remission within 3 months. Conclusion:Among RA patients, the disease activity of RA patients is closely related to RF and the RF(+) patients have more severe disease than RF(-) patients. Patients with higher RF titer also have more severe disease than that of patients with low RF titer. After 3 months of medication treatment, the antibody status does not affect the disease remission rate.

Depression is a common disease that affects human mental health in today’s society. The establishment of animal model of depression is of great significance to the study of depression. In recent years, people’s research on depression has gradually increased, and the modeling methods of depression animals have been gradually enriched. Due to the reasons of operation and cost, the modeling of depression in rodents is more common and mature. At present, the main animal models of depression include stress model, drug model, surgical model and genetic model. Each model has its own advantages and disadvantages. Appropriate methods can be selected according to the research purpose, so as to conduct in-depth research on depression. Recent studies have found that some brain signal pathways have become new targets for the treatment of depression. These signal pathways are closely related to depression, and the drugs acting on these targets have significant curative effects. Therefore, this paper reviewed the research progress of animal models and signal pathways of depression in recent years, so as to provide a theoretical basis for the study of the pathogenesis of depression.