[Preliminary investigation of animal model of tibial defection fracture made by drilling hole method ].

OBJECTIVE: To compare the differences in damage degree, healing time and healing process between two animal models of defection fracture and provide the research data for the establishment of a new animal model. METHODS: Sixty male SPF Spragur-Dawley rats were divided randomly into control group, sawing group and drilling hole group, with 20 rats in each group. Animals of drilling hole group were treated with hone drill and made an 1 mm hole on tibial plateau animals of sawing group were treated with saw and made an 3 mm defection on tibial plateau; nothing to do in animals of control group. The rats were respectively killed at 2nd, 4th weeks after operation, bone density, bone ash quantity, contents of bone Ca, P were detected. RESULTS: At the 2nd week after operation, bone density, bone ash quantity, contents of bone Ca, P in drilling hole group and sawing group were significantly lower than that of the control group (P < 0.05 or P < 0.01). Two animal models of drilling hole group and sawing group were similar in X-ray films and pathology investigations. At the 4th week after operation, there were no significant defference in bone density and bone ash quantity among three groups (P > 0.05). Rats of sawing group showed more poroma and inflammatory infiltration in histological examination. CONCLUSION: Drilling hole method and sawing method could be used to make animal model of defection fracture, two methods showed similar damage degree, healing time and healing process, hut drilling hole method have advantages of simple operation, easily control damage degree and less inflammatory infiltration and bone disunion.

Enhanced chemiluminescence of the luminol-hydrogen peroxide system by colloidal cupric oxide nanoparticles as peroxidase mimic.

As a peroxidase mimic, cupric oxide nanoparticles were found to enhance the chemiluminescence (CL) of luminol-H(2)O(2) system up to 400 folds. The CL spectra and radical scavengers were conducted to investigate the possible CL enhancement mechanism. It was suggested that the enhanced CL could be attributed to the peroxidase-like activity of CuO nanoparticles, which effectively catalyzed the decomposition of hydrogen peroxide into hydroxyl radicals. The effects of the reactant concentrations and some organic compounds were also investigated. The proposed method could be used as a sensitive detection tool for hydrogen peroxide and glucose.

Analysis of risk factors for retinopathy of prematurity.

AIM: To analyze the incidence and risk factors for retinopathy of prematurity (ROP). METHODS: A retrospective analysis was conducted on 568 premature infants from September 2005 to December 2010 with birth weight(BW) equal to or less than 2 500g or a gestational age(GA) at birth of 34 weeks or less. All of the members were examined by indirect binocular ophthalmoscopy. RESULTS: ROP occurred with an incidence rate of 10.7% among 568 premature infants, and stages 3 and above ROP occurred with an incidence rate of 2.5%. This study showed the infants were more prone to develop ROP with short geststional age, low BW, long time of oxygen inhalation, and severe infants diseases. Twins had a significantly higher rate of ROP(18.3%) than singleton babies(9.8%), ROP were severer in twins than singleton babies. CONCLUSION: Short GA, low BW, long time of oxygen inhalation, severe infants diseases, and non-singleton babies were the most significant risk factors associated with ROP.

Possible association of ACE gene I/D polymorphism with blood pressure--lowering response to hydrochlorothiazide.

OBJECTIVE: To explore the association between polymorphism in the ACE I/D gene and blood pressure-lowering response to hydrochlorothiazide (HCTZ) in 829 patients. METHODS: HCTZ 12.5 mg was taken once a day for six weeks. The blood pressure reduction and ratio reaching target blood pressure were compared in different ACE genotype groups. RESULTS: The reduction in SBP of patients carrying DD was greater than that in other groups carrying II or ID (12.2 mmHg versus 5.4 mmHg, 12.2 mmHg versus 4.4 mmHg, respectively, P<0.05). The reduction in MAP of patients carrying DD was also greater than that in other groups carrying II or ID (6.9 mmHg versus 3.9 mmHg, 6.9 mmHg versus 3.6 mmHg, respectively, P<0.05). The ratio reaching target blood pressure in DD groups was significantly higher than that in II or ID groups (P<0.05). The pre-treatment SBP, DD genotype, aldosterone levels entered the multi-linear regression model significantly and might affect the reduction of SBP. The pre-treatment DBP, aldosterone levels, DD genotype entered the multi-linear regression model significantly and might affect the reduction of DBP. The pre-treatment MAP, DD genotype, aldosterone levels entered the multi-linear regression model significantly and might affect the reduction of MAP. CONCLUSION: ACE genotyping is associated with blood pressure-lowering response to HCTZ. Specific genotypes might be associated with the response to specific antihypertensive treatment.