circ_0003204 regulates the osteogenic differentiation of human adipose-derived stem cells via miR-370-3p/HDAC4 axis / 国际口腔科学杂志·英文版

Human adipose-derived stem cells (hASCs) are a promising cell type for bone tissue regeneration. Circular RNAs (circRNAs) have been shown to play a critical role in regulating various cell differentiation and involve in mesenchymal stem cell osteogenesis. However, how circRNAs regulate hASCs in osteogenesis is still unclear. Herein, we found circ_0003204 was significantly downregulated during osteogenic differentiation of hASCs. Knockdown of circ_0003204 by siRNA or overexpression by lentivirus confirmed circ_0003204 could negatively regulate the osteogenic differentiation of hASCs. We performed dual-luciferase reporting assay and rescue experiments to verify circ_0003204 regulated osteogenic differentiation via sponging miR-370-3p. We predicted and confirmed that miR-370-3p had targets in the 3'-UTR of HDAC4 mRNA. The following rescue experiments indicated that circ_0003204 regulated the osteogenic differentiation of hASCs via miR-370-3p/HDAC4 axis. Subsequent in vivo experiments showed the silencing of circ_0003204 increased the bone formation and promoted the expression of osteogenic-related proteins in a mouse bone defect model, while overexpression of circ_0003204 inhibited bone defect repair. Our findings indicated that circ_0003204 might be a promising target to promote the efficacy of hASCs in repairing bone defects.

Parathyroid hormone increases alveolar bone homoeostasis during orthodontic tooth movement in rats with periodontitis via crosstalk between STAT3 and β-catenin / 国际口腔科学杂志·英文版

Periodontitis patients are at risk of alveolar bone loss during orthodontic treatment. The aim of this study was to investigate whether intermittent parathyroid hormone (1-34) treatment (iPTH) could reduce alveolar bone loss during orthodontic tooth movement (OTM) in individuals with periodontitis and the underlying mechanism. A rat model of OTM in the context of periodontitis was established and alveolar bone loss was observed. The control, iPTH and iPTH + stattic groups received injections of vehicle, PTH and vehicle, or PTH and the signal transducer and activator of transcription 3 (STAT3) inhibitor stattic, respectively. iPTH prevented alveolar bone loss by enhancing osteogenesis and suppressing bone resorption in the alveolar bone during OTM in rats with periodontitis. This effect of iPTH was along with STAT3 activation and reduced by a local injection of stattic. iPTH promoted osteoblastic differentiation and might further regulate the Wnt/β-catenin pathway in a STAT3-dependent manner. The findings of this study suggest that iPTH might reduce alveolar bone loss during OTM in rats with periodontitis through STAT3/β-catenin crosstalk.

Influencing factors of lateral lymph node metastasis in papillary thyroid carcinoma / 国际肿瘤学杂志

Papillary thyroid carcinoma is the most common pathology type of thyroid carcinoma with the following biological characteristics:low malignancy,slow progress,longer duration,good prognosis,but it is prone to lymph node metastasis.Lateral lymph node metastasis relates with patients' age,sex,tumor size,tumor location,capsular invasion/extra-thyroidal extension,muli-focality and the number of positive central lymph nodes.Understanding the influencing factors of the lateral lymph node metastasis has important clinical significance for determining the lymph node dissection scope and the indications for the patients with thyroid carcinoma.

Proliferation and differentiation of rat bone marrow mesenchymal stem cells under different mechanical strains / 中国组织工程研究

BACKGROUND:In vitro and in vivo studies of cel response to a variety of mechanical loadings have demonstrated the stimulation of bone formation by loads. However, the effects of different mechanical strains on the same cel s have never been adequately studied by far. OBJECTIVE:To investigate the effects of different mechanical strains on rat bone marrow mesenchymal stem cel s. METHODS:Rat bone marrow mesenchymal stem cel s were isolated and cultured in vitro. Bone marrow mesenchymal stem cel s were subjected to different stimulations including dynamic stretch, static stretch and hybrid stretch through the use of custom-made mechanical stretch device. Cel ular proliferation, alkaline phosphatase activity and mRNA expression of Runx2 of bone marrow mesenchymal stem cel s were detected and the secretion of osteocalcin was evaluated under three different stretch modes respectively. RESULTS AND CONCLUSION:Compared to the control group, cel proliferation increased by 18.67%, however, alkaline phosphatase activity, Runx2 expression and osteocalcin secretion were not changed obviously in the static stretchgroup. Compared to the control group, alkaline phosphatase activity, Runx2 expression and osteocalcin secretion increased by 60.33%, 49.67%and 48%respectively;however, cel proliferation was inhibited, in the dynamic stretch group. Compared to the control group, cel proliferation was slightly, but not significantly, increased in the hybrid stretch group, and the alkaline phosphatase activity, Runx2 expression and osteocalcin secretion increased although the increases were not as apparent as those in the dynamic stretch group. These findings suggest that static mechanical strain can significantly promote cel proliferation, the dynamic mechanical strain more greatly promotes osteogenic differentiation of bone marrow mesenchymal stem cel s, and the hybrid mechanical strain promotes the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cel s.

Meta analysis of soft tissue profile repair in patients treated with and without premolar extraction / 中国组织工程研究

OBJECTIVE: To analyze the impact of extraction and nonextraction in soft tissue profile repair. METHODS: Databases of CNKI, Wanfang, VIP Chinese Periodical Database, CBM, Medline (ovid) and Science direct had been searched for studies of soft tissue profile after orthodontic treatment with and without extractions published in recent decade, with orthodontics, corrective, tooth extraction, soft tissue profile as key words. Hand searching was also done to obtain any further information about the studies. Meta analysis was used to comprehensively quantitatively analyze the upper (lower) lip with esthetic plane and soft tissue plane before and after extraction and nonextraction treatment. According to homogeneity test, fixed effect model and random effect model were adopted to calculate weighted mean difference (WMD) and 95% confidence interval (95% Cl).Revman 5.0 was used for data management. RESULTS: Five studies with 356 patients were included. Homogeneity test showed that lower lip-esthetic line and lower lip-soft tissue line Ⅰ~2 < 50%, without heterogeneity, so fixed effect model was adopted. Upper lip-esthetic line and upper lip-soft tissue line were more than 50%, indicating heterogeneity, so random effect model was adopted. Result of meta-analysis showed that, the WMD value and 95% Cl of lower lip-esthetic line, lower lip-soft tissue line, and upper lip-soft tissue line has statistically significance. CONCLUSION: The extraction treatment significantly decreased the distance of lower lip-esthetic line, lower lip-soft tissue line, and upper lip-soft tissue line.

Establishment of a rat midpalatal suture expansion model / 中国组织工程研究

BACKGROUND: Monkeys, dogs, pigs, rabbits and other large animals have bean applied previously to prepare animal models of midpelatel suture expansion, but there are high cost, small sample size, difficult to obtain antibodies and other disadvantages, Wistar rats have wide heads to facilitate cavity operation, with low cost and high reproduction rata, as the midpalatal suture model, it is possible to overcome the above deficiencies. OBJECTIVE: To establish a rat model of midpalatal suture expansion, and to supply basement for further relative researches of animal models. METHODS: Twenty Wistar male rats of 5 weeks old, average weight of 65 g, were randomly divided into 2 groups, a experiment and a control, with 10 rats in each group. Rats in experimental group were placed on the expansion appliance, inserting into the diastema between the first and second molars, then stick to molar lingual using light-cured resin for retention. The rats in control group were sham operated, followed by one weak of active expansion. After expansion, the midpalatal sections were observed by X-ray and light microscopy. RESULTS AND CONCLUSION: Maxillary X-ray film showed that midpalatal suture in experimental group was significantly widened, molar lead to cheek. Observed by light microscopy, partial oral side of midpalatal suture in the experimental group was obviously enlarged, mesenchymst ceils were spindle, in the same direction to tension force, Below it, traumatic inflammatory response appeared, with a clear bleeding area. The midpalatal suture expansion model in rats is available, simple and reprodudble.

Reoperation for thyroid cancer / 中国耳鼻咽喉头颈外科

OBJECTIVE To study the results of the reoperation for thyroid cancer. METHODS The clinical data of 288 cases who underwent reoperation for thyroid cancer were analyzed retrospectively. There were 69 male and 219 female. There were 249 cases (86.5 %) with papillary adenocarcinoma, 27 cases(9.4 %) with follicle adenocarcinoma, 6 cases (2 %) with medullar cancer, and 6 cases (2 %) with anaplastic cancer pathologically. The types of operation were lobectomy and near total lobectomy. The unilateral or bilateral neck dissections were performed in selected cases. RESULTS Pathological examination reveal that there were 63 cases of cancer residual in the ipsilateral side and 33 cases of the opposite side. The cervical node metastasis were present in 164 cases of patients at the same side. CONCLUSION The ipsilateral side lobaectomy and/or contralateral side near total lobectomy should be employed for the thyroid cancer patients. The neck dissection should be performed in most of the patients.

Expression of matrix metalloproteinase-3 and tissue inhibitor metalloproteinases-1 in regenerated rabbit bone after mandibular osteodistraction / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To observe the expression patterns of matrix metalloproteinase-3 and its inhibitor, tissue inhibitor metalloproteinases (TIMP)-1, in remodeling phase of mandibular distraction osteogenesis.</p><p><b>METHODS</b>Bilateral mandibular osteotomies were performed in 8 mature rabbits. The mandibles were lengthened 6 mm using a custom-made distractor with a rate of 1 mm/d. All animals were killed in 4 weeks after completion of distraction. The distracted calluses were harvested and processed for histology and immunohistochemistry of MMP-3 and TIMP-1.</p><p><b>RESULTS</b>Elevated expression of both MMP-3 and TIMP-1 was found in the distracted calluses resulting from mandibular lengthening. Positive staining for MMP-3 was seen in the osteoblasts and osteocytes, and TIMP-1 was mainly localized in osteoblasts.</p><p><b>CONCLUSION</b>MMP-3 and TIMP-1 appear to play important roles in the remodeling of new bone created by mandibular distraction osteogenesis.</p>

Changes in the inferior alveolar vessels and angiogenesis following mandibular lengthening with different rates of distraction / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The purpose of this study was to study the changes in the inferior alveolar vessels and angiogenesis following mandibular lengthening with different rates of distraction.</p><p><b>METHODS</b>Bilateral mandibular corticotomies were performed in 6 goats. The mandibles in 6 goats were lengthened 10.0 mm using a custom-made distractor with different rates of distraction (1.0 mm/d[n = 3] and 2.0 mm/d [n = 3]); the other 2 nondistracted mandibles served as control. The goats with distracted mandibles were killed at 2 weeks after completion of distraction. The inferior alveolar vessels with distracted calluses were harvested and processed for histologic and morphometric evaluation.</p><p><b>RESULTS</b>No pathological changes in the inferior alveolar vessels were found following mandibular osteodistraction. However, the number of microvessels within distraction gap in the animals distracted at a rate of 1.0 mm/day was greater than that in the goats distracted using a rate of 2.0 mm/day, and more mature newly formed bone trabeculae was observed.</p><p><b>CONCLUSION</b>There were no significant changes in the inferior alveolar vessels after mandibular lengthening with distraction osteogenesis, but rapid distraction may have adverse effects on the aniogenesis in the distraction gap.</p>

Changes in the temporomandibular joint after unilateral mandibular distraction osteogenesis / 实用口腔医学杂志

objective: To observe the changes in the bilateral condyles after unilateral mandibular lengthening with distraction osteogenesis. Methods: Unilateral mandibular osteodistraction (DO) was performed in 8 goats. 4 animals were sacrificed at 8 and 16 weeks after completion of distraction respectively. The TMJ specimens were harvested and processed for histologic, histomorphometric and scanning electron microscopic (SEM) examinations. Results: Reversible adaptive remodeling in the condyles was observed following mandibular distraction at a rate of 1 mm/d. No degenerative changes in the TMJs were found after mandibular lengthening. Conclusion: Gradual distraction at a rate of 1 mm/day may not lead to degenerative change in condylar cartilage.

Effects of mechanical strain on proliferation of human osteoblast-like cells / 实用口腔医学杂志

Objective: To study the effects of mechanical strain on the proliferation of human osteoblasts. Methods: Cloned MG 63 human osteoblasts were cultured and seeded at 10 5/well in 6 well Bioflex cell cuture plates. Subsequently, the cells were exposed to mechanical strain stimulation (at 6%, 12% and 24% elongation rate respectively) for 24 hours using Flexercell 3000 Cell Stretching Unit. MTT colorimetric method was used to assess the proliferation of the cells. Results: The proliferation of MG 63 cells was significantly increased 24 h after mechanical strain treatment( P

The changes of cranial suture induced by the distraction forces in growing goats / 实用口腔医学杂志

Objective:To observe the response and changes of cranial suture to the distraction forces in growing goats.Methods:A custom-made distractor was used for expanding coronal suture of 11 growing goats at the rate of 0.4 mm/day for 8 days.The animals were killed 0,2 and 4 weeks respectively after completion of suture distraction application. X-ray examination was taken and the distracted suture samples were harvested and processed for scanning electron microscopic observation and immunohistochemistry examination of BMP and TGF-? expression. The coronal sutures taken from other undistracted animals were used as the controls. Results:The coronal sutures were separated successfully in distracted goats. 0 and 2 weeks after application of suture distraction, the collagen fiber bundles were strengthened and aligned in the direction of the distraction. Strong expression of BMP and TGF-? were detected in the fibroblast-like cells and the active osteoblasts. 4 weeks after suture distraction, signs of intramembranous ossification were found in the edge areas of the distracted suture, and the positive staining of BMP and TGF-? was still noted in the osteoblasts around the newly formed bone trabeculae. Conclusion:BMP and TGF-? may play important roles in the process of bone formation and remodeling during suture distraction osteogenesis.