The mechanism of action of Lipiburn on fat metabolism.

Paeoniflorin (PF) is the active ingredient in Lipiburn, a fat loss supplement. PF is a component in Paeonia Lactiflora with multiple medicinal uses. Here, we studied the effect of Lipiburn on fat metabolism in differentiated 3T3-L1 adipocytes. Adipocytes exposed to Lipiburn exhibited significant increase in expression of beta-adrenergic receptors, HSL levels, and cAMP and exhibited increase in glycerol release. The data show that Lipiburn affects fat metabolism through the cAMP route by activating HSL which in turn breaks down triglycerides into glycerol and fatty acids.

Prevalence of supernumerary teeth based on panoramic radiographs revisited.

PURPOSE: The purposes of this study were to: (1) identify, within the literature, reports on the prevalence of supernumerary teeth that have used panoramic radiographs (PRs) as a diagnostic tool; and (2) reanalyze the prevalence data based on the current sensitivity figures for PRs in identifying supernumerary teeth. METHODS: A comprehensive literature search in three databases identified 16 potential studies, of which seven were included in the final analysis. Based on the recent sensitivity data for PRs in identifying supernumerary teeth, the equation "P=r/q" was derived to reanalyze the prevalence data. Multiple regression analysis and paired t test were employed for the statistical analysis. RESULTS: The prevalence figure ranged from 1.2 percent to three percent, and, subsequent to the application of the adjustment factor, it increased to range from 2.4 percent to six percent. The prevalence figures for males was significantly higher than for females (RR=1.37). Furthermore, due to insufficient studies, statistical analysis was unable to elicit ethnical differences in the prevalence figures. CONCLUSIONS: The prevalence of supernumerary teeth is higher than indicated in the published reports and ranges from 2.4 percent to six percent or possibly even higher.

Human dental pulp stem cells expressing transforming growth factor ß3 transgene for cartilage-like tissue engineering.

BACKGROUND AIMS: The aim of this study was to engineer sizable three-dimensional cartilage-like constructs using stem cells isolated from human dental pulp stem cells (DPSCs). METHODS: Human DPSCs were isolated from teeth extracted for orthodontic treatment and enriched further using immuno-magnetic bead selection for stem cell marker CD146. Chondrogenic lineage differentiation of DPSCs induced using recombinant transforming growth factor ß3 (TGFß3) was verified by pellet culture. Because the use of recombinant proteins is associated with rapid degradation and difficult in vivo administration, we constructed the recombinant adeno-associated viral vector encoding human TGFß3 and determined the best multiplicity of infection for DPSCs. Transduced DPSCs were seeded on poly-l-lactic acid/polyethylene glycol (PLLA/PEG) electrospun fiber scaffolds demonstrating proper attachment, proliferation and viability as shown by scanning electron microscopy micrographs and CCK-8 cell counting kit. Scaffolds seeded with DPSCs were implanted in the back of nude mice. RESULTS: Transduced DPSCs highly expressed human TGFß3 for up to 48 days and expressed chondrogenic markers collagen IIa1, Sox9 and aggrecan, as verified by immunohistochemistry and messenger RNA (mRNA). Immunohistochemistry for TGFß3/DPSC constructs (n = 5/group) showed cartilage-like matrix formation with glycosaminoglycans. In vivo constructs with TGFß3/DPSCs showed higher collagen type II and Sox9 mRNA expression relative to non-transduced DPSC constructs (n = 5/group). Western blot analysis confirmed this expression pattern on the protein level (n = 3/group). CONCLUSIONS: Immuno-selected DPSCs can be successfully differentiated toward chondrogenic lineage, while expressing the chondrogenic inducing factor. Seeded on PLLA/PEG electrospun scaffold, human DPSCs formed three-dimensional cartilage constructs that could prove useful in future treatment of cartilage defects.

The adjunct effectiveness of diode laser gingivectomy in maintaining periodontal health during orthodontic treatment.

OBJECTIVE: To evaluate the effectiveness of diode laser gingivectomy as an adjunct to nonsurgical periodontal treatment in the management of periodontal health among patients receiving fixed orthodontic appliance therapy (FOAT). MATERIALS AND METHODS: Thirty patients undergoing FOAT with gingival enlargement were block randomized into two treatment groups. The test group received diode laser gingivectomy (940-nm diode laser, ezlase, Biolase Technology Inc) as an adjunct to nonsurgical periodontal treatment. The control group received nonsurgical periodontal treatment only. For both groups, five periodontal parameters were assessed at baseline, 1 month, 3 months, and 6 months: Plaque Index, Gingival Index, bleeding on probing, probing pocket depth, and Gingival Overgrowth Index. Intra- and intergroup variations in the periodontal parameters were determined over time. RESULTS: Both groups showed statistically significant improvements in periodontal health over the study period (P < .05). However, significant improvements in periodontal health were evident earlier among the test group subjects (P < .05). The magnitude of improvement in periodontal health compared to baseline was greater in the test group than in the control group for Gingival Overgrowth Index at 1 month (P < .001) and 3 months (P < .05), Gingival Index at 3 months (P < .05) and 6 months (P < .05), and probing pocket depth at 1 month (P < .05). CONCLUSIONS: Nonsurgical periodontal management with or without the adjunct use of lasers can be effective in the management of gingival health problems among patients receiving FOAT. The adjunctive use of lasers can produce an earlier and greater improvement in gingival health.

The effect of naringin on early growth and development of the spheno-occipital synchondrosis as measured by the expression of PTHrP and Sox9--an in vitro model.

The aim of this study was to assess the effect of the flavonoid naringin on the growth of the spheno-occipital synchondrosis by quantifying the levels of expression of Sox9 and PTHrP in an in vitro mouse model. Fifty 1-day-old BALB/c mice were randomly assigned to experimental or control groups, and each group equally divided into five time frames (6, 24, 48, 72 and 168 hours). The mice were sacrificed with phenobarbitone sodium, and the spheno-occipital synchondroses dissected and cultured in control or experimental medium, with the experimental medium supplemented with 0.1 µm naringin. Sections of the specimens underwent immunohistochemical staining for Sox9 and PTHrP, and the amount of expression was quantified using true-colour RGB (red-green-blue) computer-assisted image-analysing system with digital imaging. Data analysis showed there was a significant increase of expression of Sox9 at 6 and 24 hours (P < 0.001) between experimental and control groups, however, there was no significant difference between the levels of expression of PTHrP between experimental and control groups at any of the time frames. There was a very weak correlation found in this study between the expression of PTHrP and Sox9. In conclusion, naringin enhances the growth of the spheno-occipital synchondrosis through over expression of Sox9. This is a successful in vitro model to study factors regulating the growth of the spheno-occipital synchondrosis.

Evaluation of the long-term storage stability of saliva as a source of human DNA.

OBJECTIVES: The objectives of this paper are to determine the storage stability of saliva at 37 °C over an 18-month period, and its influence on the DNA yield, purity, PCR protocols and genotyping efficacy. MATERIALS AND METHODS: Of the 60 participants, blood samples were obtained from 10 and saliva from 50. Samples were subjected to different storage conditions: DNA extracted immediately; DNA extracted following storage at 37 °C for 1, 6, 12 and 18 months. Subsequently, DNA yield, OD(260/280) and OD(260/230) ratios were measured. The isolated DNA was used to amplify exons 0-7 of the RUNX2 gene and subsequently sequenced. Furthermore, 25 SNPs were genotyped. RESULTS: The mean DNA yield, OD(260/280) and OD(260/230) ratios obtained from blood were 67.4 ng/µl, 1.8 ± 0.05 and 1.8 ± 0.4 respectively. DNA yield obtained from saliva was significantly higher than blood (p < 0.0001), ranging from 97.4 to 125.8 ng/µl while the OD(260/280) ratio ranged from 1.8 ± 0.13 to 1.9 ± 0.1. The success rates for the 25 SNPs ranged from 98 to 100 % for blood and 96-99 % for saliva samples with the genotype frequencies in Hardy-Weinberg equilibrium (>0.01). CONCLUSIONS: Saliva can be stored at 37 °C for 18 months without compromising its quality and ability to endure genetic analyses. CLINICAL RELEVANCE: Saliva is a viable source of human DNA to facilitate the feasibility of large-scale genetic studies.

The role of vascular endothelial growth factor in ossification.

Osteogenesis and angiogenesis are two closely correlated processes during bone growth, development, remodelling and repair.Vascular endothelial growth factor (VEGF) is an essential mediator during the process of angiogenesis. Based on an extensive literature search, which was carried out using the PubMed database and the keywords of osteogenesis, VEGF, endochondral ossification and intramembranous ossification, this manuscript reviews the role of VEGF in ossification, with emphasis on its effect in endochondral and intramembranous ossification. Osteogenesis and angiogenesis are closely correlated processes. VEGF acts as an essential mediator during these processes. It not only functions in bone angiogenesis but also in various aspects of bone development.

Reliability of panoramic radiographs for identifying supernumerary teeth in children.

OBJECTIVES. To evaluate the reliability of panoramic radiographs (PRs) for identifying supernumerary teeth (ST) and to determine whether the level of dental training of the observer influenced the identification of ST. METHODS. Seventy-five PRs were randomly selected from the patient records and 18 examiners independently rated 25 radiographs each, for specific risk factors as well as for a measure of adequacy. Subsequently, the results were paired with those of the other examiners who assessed the same set of PRs. Descriptive statistics were computed using Fisher's exact test, and kappa statistics were used to assess the inter- and intra-observer reliability. RESULTS. Four hundred and fifty PRs were available for analysis. The overall sensitivity and specificity figures were 50% and 98.3%, whereas the positive and negative predictive values were 90.6% and 83.6%, respectively. The sensitivity figures for Junior House Dental Officers and Postgraduate Paediatric Dental Trainees were 39.2% and 60.8%, whereas the specificity figures were 99.4% and 95% with slight inter-examiner and moderate intra-examiner reliability. CONCLUSIONS. Panoramic radiographs are unreliable for identifying ST, and higher level of dental training is essential for identifying ST.

Analysis of genetic polymorphisms in skeletal Class I crowding.

INTRODUCTION: Dental crowding is a problem for both adolescents and adults in modern society. The purpose of this research was to identify single nucleotide polymorphisms (SNPs) responsible for crowding in subjects with skeletal Class I relationships. METHODS: The case subjects consisted of healthy Chinese people living in Hong Kong with skeletal Class I relationships and at least 5 mm of crowding in either arch. The control subjects met the same requirements but lacked crowding or spacing. SNP genotyping was performed on the MassARRAY platform. The chi-square test was used to compare genotype and allele type distributions between the case and the control groups. Logistic regression was used to calculate odds ratios with 95% confidence intervals, and the effects of age and sex for each SNP. Analyses of linkage disequilibrium and haplotype associations between SNPs were performed with software. RESULTS: Five SNPs were found to be significantly different in genotype or allele type distributions. SNP rs372024 was significantly associated with crowding (P = 0.004). Two SNPs, rs3764746 and rs3795170, on the EDA gene were found to be associated marginally. SNPs rs1005464 and rs15705 also exhibited marginal association with crowding. The effects of associated SNPs remained significant after adjustments for age and sex factors. CONCLUSIONS: This study suggests an association for the genes EDA and XEDAR in dental crowding in the Hong Kong Chinese population.

Comparison of oral impacts experienced by patients treated with labial or customized lingual fixed orthodontic appliances.

INTRODUCTION: Our objective was to compare the oral impacts experienced by patients treated with labial or customized lingual fixed orthodontic appliances. METHODS: This was an age- and sex-matched prospective longitudinal study of 60 adult patients treated with either labial or customized lingual fixed orthodontic appliances over a 3-month period. Ratings of oral impacts experienced and satisfaction were made on visual analog scales at 3 time points after appliance fixation. Variations in oral impacts and satisfaction over the trajectory of treatment were assessed. Area-under-the-curve analyses were conducted to assess variations in oral impacts and satisfaction between the groups. RESULTS: All patients experienced oral impact disturbances, although these disturbances decreased over time (P < 0.001). Patients treated with customized lingual appliances reported more oral discomfort (P < 0.001), dietary changes (P < 0.001), swallowing difficulty (P < 0.001), speech disturbances (P < 0.001), and social problems (P < 0.001) than did those in the other group. There was no significant difference between the groups regarding ratings of oral self-care, mastication, and satisfaction level of treatment (P > 0.05). CONCLUSIONS: The findings indicate that oral impacts are commonly experienced during both labial and customized lingual fixed orthodontic therapies. However, the oral impacts decreased over the observational period. Patients treated with customized lingual appliances experienced more oral impacts. Both groups had similar levels of treatment satisfaction.

Biobased poly(propylene sebacate) as shape memory polymer with tunable switching temperature for potential biomedical applications.

From the point of better biocompatibility and sustainability, biobased shape memory polymers (SMPs) are highly desired. We used 1,3-propanediol, sebacic acid, and itaconic acid, which have been industrially produced via fermentation or extraction with large quantities as the main raw materials for the synthesis of biobased poly(propylene sebacate). Diethylene glycol was used to tailor the flexibility of the polyester. The resulted polyesters were found to be promising SMPs with excellent shape recovery and fixity (near 100% and independent of thermomechanical cycles). The switching temperature and recovery speed of the SMPs are tunable by controlling the composition of the polyesters and their curing extent. The continuously changed switching temperature ranging from 12 to 54 °C was realized. Such temperature range is typical for biomedical applications in the human body. The molecular and crystalline structures were explored to correlate to the shape memory behavior. The combination of potential biocompatibility and biodegradability of the biobased SMPs makes them suitable for fabricating biomedical devices.

Effect of psoralen on bone formation.

To compare the amount of new bone and bone cells produced by psoralen in collagen matrix to that produced by collagen matrix in vivo. Eighteen bone defects, 5 mm by 10 mm were created in the parietal bone of nine New Zealand White rabbits. Six defects were grafted with psoralen mixed with collagen matrix. Six defects were grafted with collagen matrix alone (negative control--collagen) and six were left empty (negative control--empty). Animals were killed on day 14 and the defects were dissected and prepared for histological assessment. Quantitative analysis of new bone formation and bone cells were made on 100 sections (50 sections for each group) using image analysis. A total of 454% more new bone was present in defects grafted with psoralen in collagen matrix than those grafted with collagen matrix. No bone was formed in the negative control--empty group. The amount of bone forming osteoblasts was also significantly greater in the psoralen group than the negative control--collagen group. Psoralen in collagen matrix has the effect of increasing new bone formation locally in vivo. Psoralen in collagen matrix can be developed as a bone graft material.

A protocol for improved stability with Herbst appliance treatment for adults.

OBJECTIVE: To present a treatment protocol for improved stability with Herbst appliance treatment in Class II adult cases. MATERIALS AND METHODS: Sixteen Class II adults were treated at the University of Hong Kong with two phase treatment. The treatment protocol which leads to good stability was presented. RESULTS: The protocol leading to stable correction of overjet, molar relationship and enhanced forward positioning of the mandible involved 12 months Herbst appliance treatment with stepwise advancement followed by fixed appliance. CONCLUSIONS: The long term stability of Herbst appliance treatment is influenced by the treatment protocol employed. Based on the stability of the adult group in the present study, it is recommended to treat for 12 months in a step-wise manner for mandibular advancement with over correction.

Identification of SNP markers on 1p36 and association analysis of EPB41 with mandibular prognathism in a Chinese population.

OBJECTIVE: The results of a genome-wide scan suggested that chromosome locus 1p36 might be linked to the etiology of mandibular prognathism (MP) amongst Asian ethnicities. In this study, we performed a two-stage case-control association study to determine whether one or more genes that confer susceptibility to MP are located within this genomic region. DESIGN: In the first stage of the study, we examined 103 single nucleotide polymorphisms (SNPs) on 1p36 across an 8.6Mb critical region and within four candidate genes in 158 cases and 147 controls to identify genes associated with MP. In the second stage of the study, we examined an additional 23 SNPs within the erythrocyte membrane protein band 4.1 (EPB41) gene in 211 cases and 224 controls. RESULTS: Four SNPs located in the EPB41 gene showed possible allelic and genotypic associations with MP (P<0.03 and P<0.05, respectively) in the first stage. In the analysis of single SNPs in the second stage, the allele of rs4654388 showed the strongest significant association with MP (P=0.008) and the rs4654388 G-allele was associated with a significantly increased risk of MP (OR: 1.78, 95% CI: 1.16-2.74). Haplotype analysis revealed that MP was associated significantly with haplotype GTTCAGGT (P(corrected)=0.031), which included the rs4654388 G-allele. CONCLUSIONS: An association between genetic polymorphisms in the EPB41 gene and MP has been observed. Although the polymorphisms which may contribute to MP have not been determined, the results of our study suggest that the EPB41 gene could confer susceptibility to MP.

Novel method of cell-free in vitro synthesis of the human fibroblast growth factor 1 gene.

Recombinant DNA projects generally involve cell-based gene cloning. However, because template DNA is not always readily available, in vitro chemical synthesis of complete genes from DNA oligonucleotides is becoming the preferred method for cloning. This article describes a new, rapid procedure based on Taq polymerase for the precise assembly of DNA oligonucleotides to yield the complete human fibroblast growth factor 1 (FGF1) gene, which is 468 bp long and has a G+C content of 51.5%. The new method involved two steps: (1) the design of the DNA oligonucleotides to be assembled and (2) the assembly of multiple oligonucleotides by PCR to generate the whole FGF1 gene. The procedure lasted a total of only 2 days, compared with 2 weeks for the conventional procedure. This method of gene synthesis is expected to facilitate various kinds of complex genetic engineering projects that require rapid gene amplification, such as cell-free whole-DNA library construction, as well as the construction of new genes or genes that contain any mutation, restriction site, or DNA tag.

Systemic effect of Fructus Psoraleae extract on bone in mice.

Fructus Psoraleae extract is used in China for the treatment of bone diseases. The objective of the study was to investigate the systemic effect of Fructus Psoraleae extract consumption on bone histomorphology. Sixteen 8-week-old male BALB/c mice were divided into control and experimental groups. In the control group, eight mice were fed daily with distilled water. In the experimental group, eight mice were fed daily with distilled water mixed with Fructus Psoraleae extract. The mice were kept for 5 weeks and then killed. Using micro-computed tomography, 20 micro-tomographic slices with a separation of 0.25 mm were acquired to cover the proximal end of the left tibia of each mouse. Quantitative morphometry of the bone structure was performed. The results showed that consumption of Fructus Psoraleae extract significantly increased the bone volume/tissue volume ratio by 11.8%. The bone trabeculae increased by 7.1% in thickness so that the bone density was increased. To conclude, Fructus Psoraleae extract taken orally increases bone density and alters bone histomorphology.

Evaluation of bone thickness around the mental foramen for potential fixation of a bone-borne functional appliance: a computer tomography scan study.

AIM: A mandible bone-borne Herbst appliance (MBBHA) would avoid the proclination of the lower incisors that occurs with any teeth-borne functional appliance. But mapping of the bone characteristics at potential fixation areas around the mental foramen has not been carried out so far. The aim of this computer tomographic (CT) study was to evaluate bone thickness at specific positions around the mental foramen. MATERIAL AND METHODS: CT scans of 60 randomly chosen adult Hong Kong Chinese subjects (mean age 28 ± 6.3 years) were used to measure the bi-cortical bone thickness in the mandible in the mental foramen area. The thickness of buccal and lingual cortical and cancellous bone was assessed at the following locations: 10 mm (A10 mm) and 5 mm (A5 mm) anterior, 10 mm (P10 mm) and 5 mm (P5 mm) posterior, and 5 mm (Inf5 mm) below the mental foramen. RESULTS: The amount of buccal cortical bone thickness ranged between 1.89 mm, 10 mm anterior of the mental foramen, and 2.16 mm, 10 mm posterior to its location. At the A10 mm level, cortical thickness showed a marginal statistically significant difference between A5 and A10 mm. The total amount of bone thickness ranged from 10.19 to 12.06 mm. CONCLUSION: At the locations studied around the mental foramen, a mean bicortical bone thickness of 10-12 mm was measured. No large variation in the thickness was found between bicortical bone thicknesses in the measured locations around the mental foramen. Thorough evaluation on a case-by-case basis is advisable.

Repair of a defect following the removal of an impacted maxillary canine by orthodontic tooth movement: a case report.

This case report describes a 13-year-old boy with alveolar bony defect resulted from surgical removal of impacted upper canine transposed in the anterior region. The boy had a normal occlusion with malposition of upper central and lateral incisors. The treatment objectives were to align teeth, close spaces by mesial movement of the buccal segments in the upper jaw to repair bone loss. Fixed appliance with palatal root torque was used for the mesial movements, levelling, and alignment of teeth.Orthodontic tooth movement consisted of a sequence of root movement in a direction to increase the thickness of the labial cortical plate of bone, could ensure healthier periodontium. A healthier periodontium prior to space closure ensured repair of alveolar bony defect after surgical intervention. Orthodontic tooth movement should be added to our armamentarium for the repair of alveolar bony defect.