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The title complex, [Cu(2)(C(7)H(6)NO(2))(2)(C(12)H(8)N(2))(2)(H(2)O)(2)]·2C(7)H(7)NO(2)·2H(2)O, consists of a dinuclear [Cu(2)(C(7)H(6)NO(2))(2)(C(12)H(8)N(2))(2)(H(2)O)(2)](2+) cation, two Cl(-) anions, two 4-amino-benzoic acid mol-ecules and two disordered water mol-ecules (site occupancy factors 0.5). The Cu(II) ion adopts a distorted square-pyramidal geometry formed by two N atoms from the 1,10-phenanthroline ligand and two O atoms of the two 4-amino-benzoic acid ligands and one water O atom. The Cu⋯Cu separation is 3.109 (2) Å. A twofold axis passes through the mid-point of the Cu⋯Cu vector.

Objective: To explore a fabricating method of incisor all-ceramic cantilevered resin-bonded fixed partial denture (RBFPD) and evaluate their clinical performances., Methods: All-ceramic cantilevered RBFPDs were made to replace 1 missing incisor in each of 10 patients. The RBFPDs with lingual surface retainer were made of Empress II ceramic materials and luted with resin cement. The prostheses were examined at 2 weeks, 1 year and 2 years after denture insertion. Examining criteria included: fracture of bridge, marginal adaptation, secondary caries, and color match., Results: The average follow-up period was 14. 7 months. No framework fracture and retainer debonding were observed and marginal adaptation was evaluated as good. Seven RBFPDs matched the color of adjacent teeth, and other three did not match well but within the acceptable range of tooth shade difference., Conclusions: The results of this preliminary study suggest that the clinical performances of all-ceramic cantilevered RBFPDs are good in short-term evaluation, but their long-term success needs to be further investigated.

Objectives: To investigate the effect of hepatitis B virus X protein (HBx) on adriamycin-induced apoptosis of hepatocellular carcinoma cells., Methods: HBx gene fragment was amplified from subtype adr HBV plasmid by PCR, and inserted into Hind III and Kpn I sites of green fluorescent protein (GFP) eukaryotic expression vector pEGFP-C1 to construct recombinant pGFP/HBx. The pEGFP-C1 and pGFP-HBx were introduced into HepG2 cells by Lipofectamine 2000 to obtain HepG2 cells expressing GFP. GFP-HBx fusion protein was selected using G418. The expression of HBx gene was demonstrated by RT-PCR analysis. HepG2, HepG2/GFP and HepG2/GFP-HBx cells were treated with adriamycin (2.5 microg/ml), and apoptosis of the cells was determined by their morphological changes, trypan blue exclusion, and flow cytometry analysis., Results: Under a fluorescence microscope, visible expression of GFP and GFP-HBx fusion proteins were observed in HepG2/GFP and HepG2/GFP-HBx cells, even after growing over 70 generations. RT-PCR analysis showed that HBx gene was expressed in HepG2/GFP-HBx cells. Trypan blue exclusion showed adriamycin induced time-dependent cell death in HepG2 and HepG2/GFP cells while no significant cell death was observed in HepG2/GFP-HBx cells. Flow cytometry analysis showed that apoptosis rates in HepG2/GFP-HBx (3.94%) cells were significantly lower than those in HepG2 (59.03%) and HepG2/GFP cells (61.38%) at 36 hours after the adriamycin treatment (P < 0.01). No significant differences of apoptosis rates of HepG2/GFP-HBx (3.94%) and of the untreated cells (2.12%, 2.78%, 2.55%) (P > 0.05) were observed., Conclusion: A HepG2 cell line expressing GFP and GFP-HBx fusion proteins was successfully established. HBV X protein blocks adriamycin-induced apoptosis of these HepG2 cells.

Objective: To evaluate trigeminal function of patients with chronic masticatory muscle pain (MMP) using trigeminal somatosensory evoked potential (TSEP) and analyze mechanism of changes compared to the controls., Methods: Twelve chronic MMP patients and 12 matched controls participated in this study. TSEPs of bilateral masseter regions and inferior alveolar nerves were measured and compared between patient and control groups. The collected waves were concluded and those with appearance rate over 75% - 100% were selected. The latencies of waves were analyzed by use of the paired t test and independent-samples t test., Results: Five stable-appearing waves were obtained and named P1, N1, P2, N2, P3. The latency of P1 was significant reduced in patients (P < 0.05). The latencies of other waves were prolonged, but only P2 and N2 in left were significantly changed (P < 0.05)., Conclusions: TSEP latencies of chronic MMP patients changed in certain regular pattern and TSEP could be used as a parameter to disclose the trigeminal system abnormalities of the patients. The reduced latency of P1 might indicate the increasing conductivity of trigeminal nerves under level of ganglion Gasseri and the prolongation of latency of P2 was possibly related to inhibitory effects of the brain stem.

The influence of human genetics on the natural history of hepatitis B virus (HBV) infection may be diminished in endemic areas because infection at a young age predisposes to chronic HBV infection. The present study aimed to address this issue through the determination of the influences of single nucleotide polymorphisms (SNPs) of myxovirus resistence-1 (MxA) -88 G/T and interferon (IFN)-gamma +874 A/T on the natural history of HBV infection in endemic regions. One hundred adult patients with self-limiting HBV infection (positive for both anti-HBs and anti-HBc) and 340 adult patients with persistent HBV infection were recruited from southern China, an endemic area with an HBsAg carrier rate of 17.8%. SNPs of MxA -88 G/T and interferon (IFN)-gamma +874 A/T were typed using a protocol based on competitively differentiated polymerase chain reaction. A highly significant difference in the distribution of MxA -88 G/T was observed between those with persistent and self-limiting HBV infections. The latter displayed a lower frequency of the GG genotype (41.0% vs. 52.9%, P = 0.036) and a higher frequency of the TT genotype (16.0% vs. 2.4%, P = 0.000), compared to patients with persistent infection. These differences were not gender- or age-specific. However, a significant distribution difference of IFN-gamma +874 A/T was not observed. Between two groups of patients, respectively, the distribution frequencies of the AA genotype (65.0% vs. 72.8%, P = 0.139) and the TT genotype (2.0% vs. 1.2%, P = 0.894) were found. These results suggest that MxA gene -88 G/T and IFN-gamma +874 A/T behave differently in endemic HBV infections. Further study is necessary to clarify the influences of human genetics on endemic HBV infections.

Objective: To analyze influence of fiber framework design on fracture strength of posterior glass fiber-reinforced-composite resin-bonded fixed partial dentures (GFRC-RBFPD)., Methods: Based on established three-dimensional finite element models of GFRC-RBFPD for restoring the second mandibular premolar or the first mandibular molar, traditional fiber framework design and modified fiber framework design were analyzed. Two types of load, including cusp-fossa load and buccal-lingual cusp load, were selected. Load values were 400 N on premolar and 600 N on molar respectively. The fracture strength of GFRC-RBFPD was calculated., Results: Under cusp-fossa load, the fracture strength was 1340 N for both types of fiber frameworks of premolar GFRC-RBFPD, and 864 N for traditional framework and 875 N for modified framework of molar GFRC-RBFPD. Under buccal-lingual load, the fracture strength of premolar GFRC-RBFPD was 792 N for traditional framework and 1019 N for modified framework; that of molar GFRC-RBFPD was 645 N for traditional framework and 652 N for modified framework., Conclusions: The modified fiber framework obviously improved the strength of premolar GFRC-RBFPD and only slightly improved that of molar GFRC-RBFPD.

Objective: To compare the difference of stress distribution among models with different fiber frameworks., Methods: Four models were generated in Marc 2003 software. Four types of loads simulating normal mastication were selected. The stress within models was calculated, and output by means of graph and data., Results: There was stress concentration around connectors and retainers near connectors under cusp -fossa load, occlusal even load, and lateral load. When dentures were reinforced with fiber framework, area of stress concentration and principal stress max could decrease in comparison with pure composite resin bonded fixed partial denture. Under buccal-lingual load, there was another stress concentration around central fossa beside above two stress concentration areas. Only modified fiber framework constructed with both mesial-distal and lingual-buccal directional glass fiber could markedly reduce principal stress under buccal-lingual cusp loads., Conclusion: Under 4 types of loads simulating normal mastication, three critical regions were disclosed at the area of retainers adjacent connectors, connectors and occlusal central fossa and fissures. Only modified fiber framework constructed with both mesial-distal and lingual-buccal directional glass fiber could markedly reduce stress concentration under buccal-lingual cusp loads.

Background: The influence of interleukin-10 (IL-10) gene promoter polymorphisms on the mode and sequel of HBeAg seroconversion (a favorable event usually) in patients with chronic Hepatitis B virus (HBV) infection has not been clarified., Patients and Methods: IL-10 genotyping and haplotype analyses of 340 HBsAg carriers and 100 volunteers with self-limiting HBV infection from southern China, a high prevalent area of HBV were performed according to the single nucleotide polymorphisms in its promoter (-1,082, -819 and -592) using a competitively differentiated PCR., Results: High-producer genotype (GG at -1,082) or haplotype (GCC) was rarely found in patients from southern China (<1%). Intermediate-producer haplotype (ACC) was closely associated with chronic liver disease (P=0.004); compared with this, low-producer genotype (AA at -592) and haplotype (ATA) were closely associated with asymptomatic carriers (P=0.035 and 0.035). Intermediate-producer genotype (AC at -592) and haplotype (ACC) were closely associated with covert seroconversion of HBeAg (P=0.0086 and 0.0013) and progressive sequel after HBeAg seroconversion (P=0.013 and 0.0008), while, low-producer genotype (AA at -592) and haplotype (ATA) were closely associated with overt seroconversion of HBeAg (P=0.0023 and 0.0061) and silent sequel after HBeAg seroconversion (P=0.0009 and 0.001)., Conclusions: IL-10 gene promoter polymorphisms significantly influence the mode and sequel of HBeAg seroconversion in patients with chronic HBV infection.

Rapid, specific and sensitive methods without advanced equipment are required urgently in developing countries in order to detect or monitor lamivudine-resistant mutants routinely before or in the course of the therapy. A protocol is described for the detection of two major YMDD mutations simultaneously through modifying a previous competitively differentiated-PCR (CD-PCR) by revising the strategy, increasing the number of competitively differentiated primers, increasing the number of labeled haptens, optimizing the amplification system and analyzing its products by enzyme immunoassay. Special care was taken to promote the sensitivity, specificity and the ability of the protocol to detect mutation in mixture of the mutants and wild strain. YMDD mutants in clinical serum samples were detected simultaneously, specifically and rapidly only with assistance of the equipment used widely in highly prevalent areas of hepatitis B virus infection.

Aim: Immune escape mutations of HBV often occur in the dominant epitope, the second-loop of the a determinant of hepatitis B surface antigen (HBsAg). To let the hosts respond to the subdominant epitopes in HBsAg may be an effective way to decrease the prevalence of immune escape mutants. For this reason, a man-made clone of HBV S gene with the second-loop deletion was constructed. Its antigenicity was evaluated by yeast expression analysis and DNA immunization in mice., Methods: HBV S gene with deleted second-loop, amino acids from 139 to 145, was generated using splicing by overlap extension. HBV deleted S gene was then cloned into the yeast expression vector pPIC9 and the mammalian expression vector pcDNA3 to generate pHB-SDY and pHB-SD, respectively. The complete S gene was cloned into the same vectors as controls. The deleted recombinant HBsAg expressed in yeasts was detected using Abbott IMx HBsAg test kits, enzyme-linked immunoadsorbent assay (ELISA) and immune dot blotting to evaluate its antigenicity in vitro. The anti-HBs responses to DNA immunization in BALB/c mice were detected using Abbott IMx AUSAB test kits to evaluate the antigenicity of that recombinant protein in vivo., Results: Both deleted and complete HBsAg were successfully expressed in yeasts. They were intracellular expressions. The deleted HBsAg could not be detected by ELISA, in which the monoclonal anti-HBs against the alpha determinant was used, but could be detected by Abbott IMx and immune dot blotting, in which multiple monoclonal anti-HBs and polyclonal anti-HBs were used, respectively. The activity of the deleted HBsAg detected by Abbott IMx was much lower than that of complete HBsAg (the ratio of sample value/cut off value, 106+/-26.7 vs 1 814.4+/-776.3, P<0.01, t = 5.02). The anti-HBs response of pHB-SD to DNA immunization was lower than that of complete HBV S gene vector pHB (the positive rate 2/10 vs 6/10, 4.56+/-3.52 mIU/mL vs 27.60+/-17.3 mIU/mL, P = 0.02, t = 2.7)., Conclusions: HBsAg with deleted second-loop of the alpha determinant still has antigenicity, and can also raise weak anti-HBs response in mice to DNA immunization, suggesting that it is possible to develop a subdominant vaccine for preventing infections of immune escape mutants of HBV.

Aim: To design and construct an exogenous multiple epitope of helper T lymphocytes (HTL), and to evaluate its effect on anti-HBs response through DNA immunization., Methods: Artificial HTL epitope, PADRE and four other HTL epitopes from different proteins were linked together using splicing by overlap extension to generate exogenous multiple epitopes of HTL, MTE5. pcMTE5 and pcHB were generated by cloning MTE5 and fragments of HBV pre-S2/S gene into mammalian expression plasmid pcDNA3. Four chimeric plasmids were constructed by cloning MTE5 into the region of pre-S2 gene (Bam HI), 5' terminal of S gene (HincII, Xba I) and 3' terminal of S gene (Acc I) of pcHB respectively. BALB/c mice were used in DNA immunization of the recombinant plasmids. Anti-HBs was detected using Abbott IMx AUSAB test kits., Results: The sequences of MTE5 and the 6 constructs of recombinant plasmids were confirmed to be correct by DNA sequencing. The anti-HBs response of the co-inoculation of pcHB and pcMTE5 was much higher than that of the inoculation of pcHB only (136.7+/-69.1 mIU/mL vs 27.6+/-17.3 mIU/mL, P<0.01, t = -6.56). Among the 4 chimeric plasmids, only the plasmid in which MTE5 was inserted into the pre-S2 region had good anti-HBs response (57.54+/-7.68 mIU/mL), and had no significant difference compared with those of pcHB and the co-inoculation of pcHB and pcMTE5., Conclusion: Exogenous multiple epitopes of HTL had immune enhancement when they were co-inoculated with pre-S2/S gene or inoculated in the chimeric form at a proper site of pre-S2/S gene of HBV. It might suggest that it was possible to improve hepatitis B vaccine using exogenous multiple epitopes of HTL. The antibody responses were very low using DNA immunization in the study. Thus, the immune enhancement effect of exogenous multiple epitopes of HTL has to be confirmed and the effect on overcoming the drawback of the polymorphism of HLA II antigens should also be evaluated after these chimeric plasmids are expressed in mammalian cell lines.

Objective: To evaluate the mandible angle and to investigate the relationship of angle size to gender, age-group, cortical thickness at the mandibular angle (CTMA), height of mandibular residual body, and edentulous period in the elderly edentulous subjects., Methods: A total of 356 panoramic radiographs of three groups of subjects were evaluated: the young dentate group, 131 subjects (mean age: 27); the older dentate group, 97 (mean age: 64); and the elderly edentulous group, 128 (ages 76, 81, or 86). Mandibular angle size, CTMA, and height of mandibular residual body were measured from panoramic radiographs. A structured questionnaire was used to determine the history of edentulousness., Results: Difference in angle size was found between dentate men and women (P < 0.05, P < 0.001), but not between the elderly edentulous men and elderly women. The elderly edentulous subjects had larger mandibular angles than did older dentate subjects (P < 0.001). The angle size was negatively related to CTMA only among 76-year-old edentulous women (P < 0.01) and negatively associated with average height of the mandibular residual body in the edentulous men and women (P < 0.01). No association existed between angle size and duration of edentulousness., Conclusions: Elderly edentulous subjects have large mandibular angles and the angle size is correlated with low-height of the mandibular residual body, which suggests that masticatory function of natural dentition and complete denture may influence change of the mandibular angle. The significant relationship of mandibular angle size to CTMA probably indicates the effect of systemic factors on change in the mandibular angle.

Ghrelin is an acylated peptide recently identified as an endogenous ligand for the growth hormone (GH) secretagogues (GHSs) receptor (GHS-R) and is involved in a novel system for regulating GH release. To study the biological activities of ghrelin using plasmid vector administration, we constructed myogenic expression vectors containing the full length cDNA of swine ghrelin-28 (pGEM-wt-sGhln) and truncated variant (pGEM-tmt-sGhln) consisting of the first seven residues of ghrelin (including Ser3 substituted with Trp3) with addition of a basic amino acid, Lys (K) at the C-terminus. After intramuscular injection of pGEM-wt-sGhln and pGEM-tmt-sGhln, RT-PCR analysis demonstrated that the ectopic expressions of ghrelin and its variant were observed 30 days post-injection. The level of GH increased in rat serum, and was significantly higher than that of the control group 20 days post-injection with pGEM-tmt-sGhln (P < 0.05). Administration of 150 microg of pGEM-wt-sGhln and pGEM-tmt-sGhln enhanced growth in rats over 30 days and great stimulatory responses were observed at day 10 and 20 post-injection respectively, whose body weight gains were on average 15% (P < 0.05) and 21% P < 0.033 significantly heavier than controls. These results suggested that skeletal muscle might have the potential to perform post-translational acylation for ghrelin, and short ghrelin variant might have the biological effects as wild type ghrelin.

Objective: To study the mechanical properties of two kinds of composite resins reinforced by preimpregnated glass fibers., Methods: Sinfony and belleGlass composite resins were used to make standard samples (25 mm x 2 mm x 2 mm) with and without glass fibers. After all specimens were stored for 24 hours in distilled water at (37 +/- 1) degrees C, the flexural strength and flexural modulus were measured on a universal test machine., Results: Both flexural strength and flexural modulus of Sinfony composite reinforced by the glass fibers became significantly increased, which were (555.76 +/- 67.31) MPa and (12.59 +/- 3.06) GPa respectively, and 4.5 and 2.5 times much more than those of the specimens without glass fibers (P = 0); the flexural modulus of belleGlass composite became significantly increased, which was (14.10 +/- 2.88) GPa, and 0.9 time much more than the specimens without glass fibers (P = 0), but the improvement of flexural strength was not significant., Conclusion: Glass fibers can improve the mechanical properties of composite resins, but the reinforcement effect is different between different resins.

Statement of Problem: Previous reports on widening of the gonial angle in edentulous patients are conflicting. Aside from age and loss of teeth, other factors may influence change in gonial angle., Purpose: This study evaluated gonial angles from panoramic radiographs of young and older dentate subjects and elderly edentulous subjects and investigated the relationship of gonial angle size to gender, age group, cortical thickness at the gonial angle, height of the mandibular residual body, and edentulous period in elderly edentulous subjects., Material and Methods: A total of 356 panoramic radiographs of 3 groups of subjects were evaluated: the young dentate group, 131 subjects (mean age 27 years); the older dentate group, 97 subjects older than age 52 (mean age 64 years); and the elderly edentulous group, 128 subjects aged 76, 81, or 86 (mean age 80 years). The gonial angle, cortical thickness at gonial angle, and height of mandibular residual body were measured from panoramic radiographs made with the same radiographic equipment and selected according to criteria. A structured questionnaire was used to determine the history of edentulism. Paired and unpaired 2-tailed t tests served to test the difference in gonial angle measurements, and a linear regression was performed to study correlations (alpha=.05)., Results: Difference in size of the gonial angle was found between dentate men and women (P<.05 in the young and P<.001 in the older dentate group), but not between elderly edentulous men and women. The elderly edentulous subjects had significantly larger gonial angles (128.4 degrees +/- 6.6) than did the young (122.4 degrees +/- 6.6, P<.001) and older dentate subjects (122.8 degrees +/- 6.6, P<.001). The angle size was negatively related to cortical thickness at the gonial angle only among 76-year-old edentulous women (P<.01), and was associated with average height of the mandibular residual body in the edentulous men and women (P<.01). No association existed between angle size and duration of edentulism. No differences were significant in any test of intraexaminer error., Conclusion: In this study, elderly edentulous subjects had larger gonial angles than did dentate subjects. The angle size was correlated with low height of the mandibular residual body and with its cortical thickness in edentulous women.

The ectopic expression of a sheep growth hormone-releasing hormone (GHRH) from muscle tissues, using a myogenic plasmid expression vector pM-GHRH, has been shown to result in enhanced animal growth. Animal injected with pM-GHRH alone exhibited a daily weight gain rate of 0.84+/-0.02%/d (p < 0.05), while that of the control animal was only 0.73+/-0.04%/d. A more significant growth enhancement was observed in the group treated with pM-GHRH plus 0.25% bupivacaine. The animal displayed a daily weight gain rate of 0.87+/-0.03%/d (p<0.01). In addition, the group treated by pM-GHRH and bupivacaine had higher levels of growth hormone (GH) in their blood (1.18+/-0.33 ng/mL) compared with the group treated by pM-GHRH vector alone (p < 0.05). Evaluation of body composition by dissection and histochemical analysis indicated a significant increase in bulk with no organomegaly or associated pathology. PCR analysis demonstrated that there was little plasmid residue detected in the pM-GHRH treated sheep.

Objective: To compare the masticatory efficiency and the character of mandibular movement trace of the patients with complete denture (CD), complete overdenture (COD) and implant-supported overdenture (IOD)., Methods: A total of 42 subjects were rehabilitated with CD, COD and IOD respectively and wore the dentures at least half a year. Each study group was composed of 14 subjects. The masticatory function of patients were investigated by means of masticatory efficiency and mandibular movement trace. The characters of mandibular movement trace were evaluated from four aspects: the regulation of chewing cycle, centralization of end traces, the type of the contact slides and the type of the trace on the frontal plane., Results: The average chewing efficiency of almond and jujube in the IOD patients was higher than that in the CD group (P < 0.01), and the chewing efficiency of almond in COD group was higher than that in the CD group (P < 0.01). In the IOD group, there were more patients with regular chewing cycle (P < 0.05) and centralized end traces (P < 0.01) in mandibular movement than those in the CD group and COD group., Conclusions: IOD and COD benefit the fully or partially edentulous patients with a relatively good masticatory function. The patients with IOD have more regular mandibular movement than those with CD.

Objective: To study the natural head posture (NHP) of edentulous patients compared with dentate people and to understand NHP shift immediately inserting complete dentures and three months after denture wearing., Methods: The NHPs of twenty edentulous patients and twenty-two dentate subjects were recorded with cephalometric technique. The NTPs of edentulous patients were exposed three times, before inserting, right after inserting and three months after inserting dentures. The NHPs of dentate subjects were recorded once as a controlled group. Six angles measured from the radiographs were evaluated for the NHP and three angles and two linear measures for the mandibular position., Results: Compared with dentate subjects, the craniomandibular angles of the edentulous patients increased and the camber of the cervical columns decreased, but changes of the NHP were not significant. The mandible showed a significant upward moving (P < 0.05) and an insignificant forward moving. At the time of denture insertion, the camber of the cervical columns significantly increased (P < 0.05). Three months after using the dentures, the craniomandibular angles of the patients obviously decreased. (P < 0.05)., Conclusion: The shift of NHP after denture inserting does exist. The shifted NHP of the patients with dentures is a new balanced posture and closer to the normal position than the NHP of them without dentures.

Objective: To compare the clinical results of repairing bone defect of limbs with tissue engineering technique and with autogeneic iliac bone graft., Methods: From July 1999 to September 2001, 52 cases of bone fracture were randomly divided into two groups (group A and B). Open reduction and internal fixation were performed in all cases as routine operation technique. Autogeneic iliac bone was implanted in group A, while tissue engineered bone was implanted in group B. Routine postoperative treatment in orthopedic surgery was taken. The operation time, bleeding volume, wound healing and drainage volume were compared. The bone union was observed by the X-ray 1, 2, 3, and 5 months after operation., Results: The sex, age and disease type had no obvious difference between groups A and B. all the wounds healed with first intention. The swelling degree of wound and drainage volume had no obvious difference. The operation time in group A was longer than that in group B (25 minutes on average) and bleeding volume in group A was larger than that in group B (150 ml on average). Bone union completed within 3 to 7 months in both groups. But there were 2 cases of delayed union in group A and 1 case in group B., Conclusion: Repair of bone defect with tissue engineered bone has as good clinical results as that with autogeneic iliac bone graft. In aspect of operation time and bleeding volume, tissue engineered bone graft is superior to autogeneic iliac bone.