The analyses of Mycoplasma pneumoniae antibody test results in patients with respiratory tract infection / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the infection rate of Mycoplasma pneumoniae (MP) and age, sex and season.</p><p><b>METHODS</b>Passive agglutination assay was used to detect Mycoplasma pneumoniae antibodies (MP-Ab) in the serum of patients with respiratory tract infection, and MP-Ab test results in 2010 were analyzed.</p><p><b>RESULTS</b>The positive rates of 5 year test results were 30.10%; among the results, the positive rates of male and female patients were respectively 30.74% and 36.12%, the difference was statistically significant (P < 0.05); And every age group were significantly different (P < 0.001), among each group, the positive rate of 3-14 years old patients was the highest; the season was no significant difference in incidence rates; the patients of positive titer > 1:640 accounted for 10.18% of the patients.</p><p><b>CONCLUSION</b>MP infection is increasing year by year, children aged 3 to 14 has become the high-risk groups. Women are more susceptible to MP than the men and the chances of infection are throughout the year, but the most of the patients have a good prognosis.</p>

Change of expression of matrix metalloproteinase-2 in the periodontal tissues of diabetes mellitus rats during orthodontic tooth movement / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To observe the expression and distribution of matrix mentallproteinase-2 (MMP-2) in the periodontal tissues of diabetes mellitus (DM) rats during tooth movement, and to observe the affection of diabetes mellitus on the collagen metabolism.</p><p><b>METHODS</b>Eighty male Sprague-Dawley rats were used. Mesial force was applied to pull the maxillary first molar. Forty rats were rendered diabetic by injection of streptozotocin. In 3 weeks after the injection, rats were subjected to lateral tooth movement. The animals were sacrificed after 0, 3, 7, 14 and 21 days respectively. Two-step immunohistochemical method was applied to localize and examine the expression of MMP-2 in periodontal tissue of rats.</p><p><b>RESULTS</b>MMP-2 immunohistochemical results indicated that the MMP-2 expression increased and was observed on both sides periodontium of movement tooth, osteoclast, cementoblast, osteocyte, fibroblast and osteoblast appeared positive. According to the immunohistochemistry image analysis, experiment group changes was less obvious than control group. Dynamic changes of OD occured, reaching the minimum on the 7th day and then increasing slowly. IOD increased steadily, up to the peak on the 7th day, and then decreased, which still remained a high level on the 21st day.</p><p><b>CONCLUSION</b>DM alveolar bone collagen metabolism increases. DM alveolar bone reactive potency decreases in orthodontic tooth movement, weak collagen metabolism. MMP-2's activity changes regularly, in close relation to bone remodeling, and plays an important role during the orthodontic tooth movement.</p>