Objective To study the expression level of peptidylarginine deiminase 4 (PADI4) and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in the synovium of rat model of collagen-induced arthritis, and to explore their possible therapeutic role in rheumatoid arthritis.
Methods Thirty-two female Wistar rats weighing 100±20 g were randomly assigned into 3-week collagen-induced arthritis (CIA) model group (n=8), 4-week CIA model group (n=8), 6-week CIA model group (n=8), and the control group (n=8). The body weight changes of each group were recorded. The expression levels of PADI4 and PTPN22 were detected and compared by the methods of immunohistochemical staining and Western blot.
Results Arthritis of rat began to form 14 days after sensitization and the joint swelling reached peak at 28 days. The weights of the rats slowly grew both in CIA model groups and the control group. Immunohistochemical staining results showed that the positive expression of PADI4 and PTPN22 was mainly located in cartilage peripheral mononuclear cells, the cytoplasm of infiltrated cells, and bone marrow cavity. There were significant differences in the optical density of PADI4 and PTPN22 among CIA model groups and the control group (PADI4, 0.2898±0.012, 0.2982±0.022, 0.2974±0.031, 0.2530±0.013 in 3-week CIA model, 4-week CIA model, 6-week CIA model and control groups;PTPN22, 0.2723±0.004, 0.2781±0.010, 0.2767±0.008, 0.2422±0.019;all P<0.05). The expression bands of PADI4 were observed in Western blot 3 weeks after initial immunization, the thickest in the 4th week, and decreased in the 6th week. The expression bands of PTPN2 were observed at all the time points, with no obvious time-dependent trend.
Conclusions PADI4 and PTPN22 are obviously correlated with CIA in rat model. PADI4 is expressed at early stage of the disease, while the expression of PTPN22 sustains throughout the course.

To clone mouse phage antibodies against H-Y antigen from a phage antibody library, three cycles of affinity enrichment of the mouse phage antibody library with male spleen cells and two cycles of nonspecific absorption with female spleen cells were performed. The presence of mouse Fab on the phage surface was determined by ELISA and sequence analysis. 9 of 15 strains can bind to male spleen cells with the specific activity. Recombination rate of the phage antibody library clones is 60%. Sequence analysis of the PCR products of plasmid DNA of E5 clones show VH and Vkappa had common characteristics shared by other known variable region of antibodies. The mouse phage Fab antibody could be used for identifying H-Y antigen, and for the development of sex determination of early embryos in mammals.
Animals ; Base Sequence ; Cloning, Molecular ; Enzyme-Linked Immunosorbent Assay ; Female ; H-Y Antigen ; analysis ; Immunoglobulin Fab Fragments ; genetics ; immunology ; Isoantibodies ; genetics ; immunology ; Male ; Mice ; Molecular Sequence Data ; Peptide Library

Objective To understand the status of screen exposure in children with epilepsy and analyze the influencing factors for screen exposure time,providing a scientific basis for managing screen exposure in these children. Methods A convenience sampling method was used to select 275 children with epilepsy from outpatient clinics or those undergoing 24-hour electroencephalogram monitoring at two tertiary hospitals in Jinan from March to June 2023. Their parents (fathers or mothers) completed a questionnaire to collect data on screen exposure,parental screen regulation behaviors,and related information about the children and their families. The Wilcoxon rank-sum test or the Kruskal-Wallis H test was used to conduct a univariate analysis of the average screen exposure time of children on school days and weekends,as well as the daily average screen exposure time. A multivariate logistic regression analysis was used to identify the risk factors for children whose screen exposure time exceeded the recommended guidelines (average screen exposure time on school days>1 hour or average on weekends>2 hours). Results The median screen exposure duration on school days was 40 minutes,while on weekends it was 120 minutes. Among the children studied,23.1％ (63/273) had average screen exposure time exceeding 1 hour on school days,and 42.5％ (117/275) had average screen exposure time exceeding 2 hours on weekends. Four children experienced seizures while using screen devices. Multivariate logistic regression analysis indicated that using screen devices shortly before sleep,lower educational levels of parents,caregivers discussing screen content with children,and longer seizure durations in children were risk factors for exceeding recommended guidelines (P<0.05). Conclusions Some children with epilepsy have a screen exposure time exceeding the recommended guidelines. A longer seizure duration,lower parental education levels,and permissive digital parenting are closely associated with children's screen exposure time exceeding the recommended guidelines. Families and children exhibiting these characteristics should be prioritized for attention and health education.

OBJECTIVETo study the expression level of peptidylarginine deiminase 4 (PADI4) and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in the synovium of rat model of collagen-induced arthritis, and to explore their possible therapeutic role in rheumatoid arthritis.

METHODSThirty-two female Wistar rats weighing 100±20 g were randomly assigned into 3-week collagen-induced arthritis (CIA) model group (n=8), 4-week CIA model group (n=8), 6-week CIA model group (n=8), and the control group (n=8). The body weight changes of each group were recorded. The expression levels of PADI4 and PTPN22 were detected and compared by the methods of immunohistochemical staining and Western blot.

RESULTSArthritis of rat began to form 14 days after sensitization and the joint swelling reached peak at 28 days. The weights of the rats slowly grew both in CIA model groups and the control group. Immunohistochemical staining results showed that the positive expression of PADI4 and PTPN22 was mainly located in cartilage peripheral mononuclear cells, the cytoplasm of infiltrated cells, and bone marrow cavity. There were significant differences in the optical density of PADI4 and PTPN22 among CIA model groups and the control group (PADI4, 0.2898±0.012, 0.2982±0.022, 0.2974±0.031, 0.2530±0.013 in 3-week CIA model, 4-week CIA model, 6-week CIA model and control groups; PTPN22, 0.2723±0.004, 0.2781±0.010, 0.2767±0.008, 0.2422±0.019; all P <0.05). The expression bands of PADI4 were observed in Western blot 3 weeks after initial immunization, the thickest in the 4th week, and decreased in the 6th week. The expression bands of PTPN2 were observed at all the time points, with no obvious time-dependent trend.

CONCLUSIONSPADI4 and PTPN22 are obviously correlated with CIA in rat model. PADI4 is expressed at early stage of the disease, while the expression of PTPN22 sustains throughout the course.

Animals ; Arthritis, Experimental ; enzymology ; metabolism ; Blotting, Western ; Collagen ; administration & dosage ; Female ; Hydrolases ; metabolism ; Immunohistochemistry ; Protein Tyrosine Phosphatase, Non-Receptor Type 22 ; metabolism ; Protein-Arginine Deiminases ; Rats ; Rats, Wistar ; Synovial Membrane ; enzymology ; metabolism