ABSTRACT
<p><b>OBJECTIVE</b>To observe the effect of different time windows and interventions on skin pressure ulcers and ischemia-reperfusion (I/R) injury in rats.</p><p><b>METHODS</b>Sixty?eight SD rats were randomly divided into blank control group (n=4) and model group (n=64). The rats in the model group were randomly divided into group A (n=32) without intervention and group B (n=32) with post?conditioning. The degree of skin compression, neutrophil infiltration and serum levels of free radicals were observed in the rats after compression for 2, 4, 6, and 8 h (8 rats at each time point).</p><p><b>RESULTS</b>A significant difference was found in the severity of skin damage among the control group, group A, and group B (P=0.001), and the injury was milder in group B than in group A. Severe skin lesions occurred in 2 rats after skin compression for 6 h, as compared with 6 after compression for 8 h (P=0.043), but in none of the rats after compression for 2 or 4. Seventeen rats in group B and 15 in group A showed grade 1 neutrophil infiltration in the skin lesions, and 8 rats in group B and 10 in group A showed grade II neutrophil infiltration (P=0.002). Neutrophil infiltration was the mildest in rats with a 2?h compression, and exacerbated progressively and significantly as the compression time extended (P=0.027). With the prolongation of the intervention time, the rats in both groups A and B showed decreased SOD and increased MDA and NO levels, and overall the I/R injury was milder in 2? and 4?h compression groups than in 6? and 8?h compression groups. The level of serum SOD was significantly higher and MDA and NO levels were significantly higher in group B than in group A (P<0.05).</p><p><b>CONCLUSION</b>Ischemic post?conditioning can relieve I/R injury in acute pressure ulcer in rats. The effective time window for intervention is within 6 h of ischemia, and the effect of ischemic post-conditioning is optimal within 2 h. Ischemic post?conditioning can alleviate free radical injury and inflammation caused by I/R injury.</p>
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the sensitivity and specificity of CD8CD28/CD8CD28T lymphocyte balance in predicting the gastrointestinal hemorrhage (GH) in patients with inflammatory bowel disease (IBD).</p><p><b>METHODS</b>Forty-nine IBD patients, including 30 with ulcerous colitis (UC) and 19 with Crohn's disease (CD), were enrolled to test peripheral blood CD8CD28and CD8CD28T cells using flow cytometry. All the patients were followed up for one year. The receiver-operating characteristic (ROC) curves were used to test the efficiency of CD8CD28/CD8CD28T lymphocyte balance to predict GH. The differences in lasting time of remission (LTR) under different factors were compared using Kaplan-Meier survival analysis, and the correlation between CD8T lymphocytes and the factors were analyzed.</p><p><b>RESULTS</b>The utilization rates of immunosuppressant, steroids, and biological agent (BA) were significantly higher in CD patients than in UC patients (P=0.003, 0.043 and 0.002, respectively). The frequencies of CD8CD28T cells were obviously higher in UC patients than those in CD patients (t=3.022, P=0.004). CD8CD28T cells, CD8CD28T cells, and especially CD8CD28/CD8CD28ratio (area under curve of 0.977, P=0.000; cut-off value of 1.14 [13.95%/12.24%] with a sensitivity of 93.3% and a specificity of 91.2%) showed good efficiencies in predicting GH (P<0.01). The mean and median of LTR of IBD patients who did not receive BA or surgical treatment were significantly longer (Χ=9.730, P=0.002; Χ=15.981, P=0.000). CD8CD28/CD8CD28ratio was significantly related to both BA (P=0.009) and surgery (P=0.038).</p><p><b>CONCLUSION</b>Both decreased CD8CD28T cells and elevated CD8CD28T cells are closely correlated with GH, and their ratio can predict the occurrence of GH with a high sensitivity and specificity and is correlated with BA and surgery at the cut-off value of 1.14.</p>
ABSTRACT
<p><b>OBJECTIVE</b>To explore the role of mast cells in the pathogenesis of ulcerative colitis in rats with dampness and heat syndrome, and observe the regulatory effect of Huangqin decoction on the mast cells.</p><p><b>METHODS</b>Rat models of dampness and heat syndrome were established by feeding with high-fat and-sugar chow, maintenance of a hot and humid environment, and intrarectal administration of 2,4,6-trinitro-benzene-sulfonic acid. The model rats were then randomized into the model group (n=12), Huangqin decoction group (n=13) and mesalazine group (n=12). After a one-week treatment, the inflammatory cell infiltration was observed using HE staining, and the number of mast cells was determined using toluidine blue staining. Immunohistochemistry was used to detect the expression of tryptase, and serum IL-4 and IL-6 levels were measured using ELISA.</p><p><b>RESULTS</b>Compared with the normal control rats (n=15), the rats in the model group showed obvious inflammatory cell infiltration at the lesion site with significantly increased mast cells and serum IL-6 level (P<0.05). Huangqin and mesalazine significantly lessened inflammatory cell infiltration and decreased the mast cell number and serum IL-6 level after a one-week treatment.</p><p><b>CONCLUSION</b>The intestinal mucosal immune cells such as the mast cells play an important role in the pathogenesis of ulcerative colitis associated with dampness and heat syndrome. Huangqin decoction can ameliorate the inflammation, decrease mast cell number and tryptase release, and inhibit IL-6 secretion for treatment of ulcerative colitis in rats with dampness and heat syndrome.</p>