Objective:To investigate the frequency of metabolic syndrome (MS) in patients with psoriatic arthritis (PsA) and further analyze the correlation of MS and its components with clinical features of PsA.Methods:Data including demographics, clinical manifestations, laboratory tests, MS-associated features (height, weight, waist circumference, blood pressure, serum lipid spectrum, and so on) and history of complications (hypertension, diabetes mellitus, atherosclerosis, coronary heart disease, and cerebral vascular disease) were collected from PsA patients in our hospital from Jan 2017 to Sep 2019. The frequency of MS in PsA patients was calculated and the association between PsA clinical manifestations and MS as well as its components was investigated.Results:One hundred and sixty-two PsA patients who fulfilled the Classification Criteria for Psoriatic Arthritis (CASPAR) were recruited. Hypertension was identified in 36 (22.2%) patients, diabetes mellitus in 28(17.2%) patients, coronary heart disease in 11(6.7%) patients, and cerebral vascular disease in 7 (4.3%) patients. Based on the criteria of the International Diabetes Federation (IDF), 58(35.8%) patients were diagnosed as MS. Compared with MS-free patients, patients with MS, hypertension or diabetes mellitus were older [(54±10 vs 44±13; 56±11 vs 45±12; 54±11 vs 44±13, respectively, t=5.058 , 4.450, 5.150, P<0.01 for all], with higher disease activity [DAPSA scores 16.75(11.25, 26.7) vs 8.8(4.8, 16.4), 16.3(9.6, 27.8) vs 10.0 (5.1, 18.0), 14.4 (9, 25.7) vs 9.5 (5, 17.7), Z=4.539 , 3.046, 3.063, P<0.01]. There was a positive correlation between the sum of components of MS and DAPSA score ( r=0.27 , P<0.01), but multiple linear regression showed no correlation between each component with DAPSA score ( P>0.05) except for hypertension ( P<0.01, standard coefficient=0.334) and elevated fasting blood glucose ( P=0.023, standard coefficient=0.247). PsA patients with hypertension had higher ESR [16.5 (9.5, 34.25) mm/1 h vs 10 (5, 24.5) mm/1 h, Z=2.127, P=0.012]. CRP level was higher in patients with dyslipidemia [5.6(2.1, 17.8) mg/L vs 3.7(1.5, 6.5) mg/L, Z=2.543, P<0.01]. Prevalence of inflammatory back pain was also higher in dyslipidemia patients (41.3% vs 22.4%, χ2=5.901, P=0.016). DAPSA score was higher in dyslipidemia patients (14.1 vs9.9, P=0.031). Conclusion:MS and its components are not rare comorbidities in PsA patients. PsA patients with MS tend to be older with higher disease activity, which calls for more attention.

Objective Comparing the effects of steam sterilization on cyclic fatigue of stainless steel files. Meth-ods Fifty instruments of 25# stainless steel K files were randomly divided into 5 groups, which include 10 in each group. Group 1 was the blank control group, group 2 to 5 were subjected to 1, 3, 4, 5 steam sterilization cycles, then the files were tested by a custom-made device to assess cyclic fatigue and the number of cycles of failure (NCF) was calculated. Microstruc-ture of each file’s fracture surface was analyzed by Scanning Electron microscope (SEM). Results NCF in the 5 groups were 4 345.2 ± 384.2,3 937.9 ± 645.4,3 812.9 ± 532.5,3 626.2 ± 380.0,3 625.9 ± 565.6 respectively, and the differences among 5 groups were significantly different(F=2.598, P<0.05). After 4 or 5 times of steam sterilization, cyclic fatigue de-creased if compared with that in control group (P<0.05). Fracture surface in group 1 and group 2 was tough dimple structure and large numbers of regular, deep dimples were distributed on the surface. You could also see micro cavities clearly formed by fracture;Fracture surface in group 4 was dimple structure in brittle intergranular morphology. It is characterized by the presence of thin brittle precipitates, clean and smooth crystal interface, and a great sense of polyhedral stereo. Conclusion After 4 times of steam sterilization, cyclic fatigue strength of 25# stainless steel K files declined, which possessed the poten-tial risk of fracture.

Animals ; Cognitive Dysfunction/therapy* ; Maze Learning ; Mice ; Protein Phosphatase 2 ; Restraint, Physical ; Stress, Psychological/therapy*

Mice ; Animals ; Humans ; Disease Models, Animal