Objective To explore the feasibility of establishing a tree shrew model of chronic gastrointestinal mucosal injury. Methods A total of 12 adult male tree shrews were randomly divided into 3 groups. The experimental groups 1 and 2 were administered with intraperitoneal injection of 2 mg/(kg·d)and 1 mg/(kg·d)of 1-methyl-4-phenyl-1,2, 3,6-tetrahydropyridine(MPTP)once every day for 56 days, respectively. The control group was given the same volume of sterile saline at the corresponding time points. Changes in the body weight of the tree shrews were observed. The contents of dopamine in the cerebrospinal fluid were detected. Gastrointestinal morphology was observed by stereoscope and histopathological changes of the gastrointestinal mucosa were examined by HE staining. Results The body weight and the contents of dopamine in the cerebrospinal fluid of the tree shrews in the model group were significantly decreased(P< 0.05 for both). Pathological changes to some extent of the gastric antrum, the gastric body and the duodenum were observed, without obvious differences between the 2 mg/kg group and the 1 mg/kg group. No obvious changes were found in the control group. Conclusions Long-term intraperitoneal injection with a low dose of MPTP is a feasible method for the establishment of a tree shrew model of chronic gastrointestinal mucosal injury. The optimal dose is 2 mg/(kg·d)every day for 56 days.

Objective To provide reference values for bone mineral density(BMD)in different skeletal regions of female Wistar rats at different ages. Methods Thirty SPF female Wistar rats were selected. The BMD of different skeletal regions(skull,upper limbs,thighs,trunk,ribs,pelvis,spine and the whole body)was measured by dual energy X-ray absorptiometry(DXA)at 6,10,12,24 and 30 months of age. The bone mineral densities between different age groups and that of different skeletal regions in the same age groups were compared. Results The BMD of the skull,upper limbs,thighs,trunk,ribs,pelvis, spine and the whole body was increased rapidly with age, and reached a peak at 10 months of age. The BMD of the skull,upper limbs,thighs,trunk,ribs were significantly higher than the whole body BMD in the same month-age group(P< 0.05 or P< 0.01). However,there was no significant difference between the pelvic, spine and the whole body BMD(P> 0.05). There was a significant positive correlation among the three correlations(P<0.01). Conclusions Some background data are provided for the bone biology studies of female Wistar rats, and provide useful supplementary reference for the studies of bone metabolism in rats and their application in biomedicine.

Rheumatoid arthritis ( RA ) is a common chronic autoimmune disease .A variety of autoantibodies appears in RA patients and the detection of autoantibodies could be used for the diagnosis and treatment for RA.Anti-citrullinated protein antibodies and rheumatoid factor has been currently used in clinical diagnosis of RA. Recently, a new widely concerned autoantibody , anti-carbamylated protein antibody , is expected to become one of the markers for early diagnosis and evaluation of disease activity and bone destruction.