[Protective effect of 2,4-dihydroxybenzophenone on cocaine-induced hepatotoxicity and neurotoxicity in mice].

OBJECTIVE: To investigate the protective effect of 2,4-dihydroxybenzophenone(BP-1) on acute hepatotoxicity and neurotoxicity induced by cocaine in mice, and its possible mechanism. METHODS: Male ICR mice were pretreated with BP-1(100,200,400 mg/kg, ig, 4 d), cocaine(75 mg/kg) was injected 30 minutes after BP-1 administration on day 4.Twenty-four hours after the injection of cocaine, the serum activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were assayed by HITACHI-7170A automatic analyzer. The content of malondialdehyde (MDA) and the content of reduced glutathione (GSH) and oxidized glutathione (GSSG) were examined, and the ratio of GSH/GSSG was calculated, and histopathological analyses were also made. Male ICR mice were pretreated with BP-1(100,200,400 mg/kg, ig, 3 d), cocaine(20 mg/kg) was injected 30 minutes after BP-1 administration on day 3.The locomotor activity during 0-180 minutes of mice was recorded individually for each animal immediately after cocaine injection. RESULTS: After the administration of cocaine, compared with corresponding solvent group, the activities of ALT [(1 571±1 161) IU/L vs. (30±16) IU/L, P<0.05], AST [(408±226) IU/L vs. (101±12) IU/L, P<0.05] and LDH [(3 963±1 431) IU/L vs. (1 935±287) IU/L, P<0.05] were significantly increased; the ratio of GSH/GSSG [(5.11±0.63) vs. (6.88±1.13),P<0.05] was decreased and the content of MDA [(1.97±1.36) µ mol/g vs. (0.07±0.06) µmol/g, P<0.01] was significantly increased. With the pretreatment of BP-1, compared with cocaine treatment group, the serum ALT [(112±96 )IU/L, (54±20) IU/L, (35±15) IU/L, P<0.05],AST [(130±33) IU/L,(107±5) IU/L, (99±9) IU/L, P<0.05] and LDH [(1 667±564) IU/L, (1 507±365) IU/L, (1 249±349) IU/L, P<0.01] were significantly decreased, the ratios of GSH/GSSG [(7.33±1.84), (9.28±0.67), (10.5±1.20), P<0.05] were increased and the contents of MDA [(1.82±1.19)µmol/g, (0.49±0.31)µmol/g, (0.35±0.30) µmol/g, P<0.05] were decreased. Significant amelioration in liver histopathology was also presented in the BP-1 treatment groups. The BP-1 pretreated mice showed significant reduction in activity counts evoked by cocaine (20 mg/kg), and shorten the time for activity counts to become normal. CONCLUSION: BP-1 has protective effect on acute hepatotoxicity and neurotoxicity of mice induced by cocaine. Its mechanisms might be associated with its antioxidant activity.

[Study of the appearance difference of lower complete denture between functional and anatomic impression techniques].

PURPOSE: To compare the difference in oblique external ridge, oblique internal ridge and alveolar process crest of lower complete denture base made through functional impression and anatomic impression techniques. METHODS: Fifteen patients were chosen to treat with two kinds of complete dentures through functional impression and anatomic impression technique respectively. 3D laser scanner was used to scan the three-dimensional model of the denture base and the differences of the surface structural between two techniques in alveolar process crest, external and internal oblique ridges were analyzed, using paired t test with SPSS 12.0 software package. RESULTS: Between the two techniques, there were significant differences in the areas of internal and external oblique ridge(P<0.01); there was no significant difference in the main support areas(P>0.05). CONCLUSIONS: The results explain why there is less tenderness when functional impression technique is applied. The differences measured also indicate that sufficient buffering should be made in external and internal oblique ridge areas in clinic.

[Clinical evaluation of unanatomic and long centric occlusal complete dentures].

PURPOSE: To compare and analyze the effect of unanatomic and long centric complete occlusal denture on the satisfaction of edentulous patients and mastication. METHODS: Sixty edentulous patients with severe resorption of residual ridge were treated with unanatomic occlusal and long centric occlusal complete dentures. One month and three months after wearing dentures, the satisfaction evaluation from edentulous patients for the different complete dentures was analyzed, and the masticatory stroke was tested, the masticatory efficiency of the two complete dentures was detected by light absorption method. SPSS 11.0 software package was used for data analysis. RESULTS: Compared with unanatomic occlusal dentures, appearance, pronunciation and comfort of long centric occlusal denture wearers were not significantly different for one and three months (P>0.05). But the masticatory function of long centric occlusal denture wearers was significantly better than anatomic occlusal denture wearers (P<0.05). CONCLUSIONS: Modified occlusion is feasible for restoration of masticatory efficiency of edentulous patients using long centric occlusal complete dentures, and they are more acceptable by edentulous patients with severe resorption of residual ridge.