Carcinogenesis promotion in oral squamous cell carcinoma: KDM4A complex-mediated gene transcriptional suppression by LEF1.

Oral squamous cell carcinoma (OSCC) is the most prevalent cancer of the mouth, characterised by rapid progression and poor prognosis. Hence, an urgent need exists for the development of predictive targets for early diagnosis, prognosis determination, and clinical therapy. Dysregulation of lymphoid enhancer-binding factor 1 (LEF1), an important transcription factor involved in the Wnt-ß-catenin pathway, contributes to the poor prognosis of OSCC. Herein, we aimed to explore the correlation between LEF1 and histone lysine demethylase 4 A (KDM4A). Results show that the KDM4A complex is recruited by LEF1 and specifically binds the LATS2 promoter region, thereby inhibiting its expression, and consequently promoting cell proliferation and impeding apoptosis in OSCC. We also established NOD/SCID mouse xenograft models using CAL-27 cells to conduct an in vivo analysis of the roles of LEF1 and KDM4A in tumour growth, and our findings show that cells stably suppressing LEF1 or KDM4A have markedly decreased tumour-initiating capacity. Overall, the results of this study demonstrate that LEF1 plays a pivotal role in OSCC development and has potential to serve as a target for early diagnosis and treatment of OSCC.

Case report: Aggressive progression of acute heart failure due to juvenile tuberculosis-associated Takayasu arteritis with aortic stenosis and thrombosis.

Background: Takayasu arteritis (TA) is a chronic granulomatous vasculitis with unknown pathophysiology. TA with severe aortic obstruction has a poor prognosis. However, the efficacy of biologics and appropriate timing of surgical intervention remain controversial. We report a case of tuberculosis (TB)-associated TA with aggressive acute heart failure (AHF), pulmonary hypertension (PH), thrombosis, and seizure, who failed to survive after surgery. Case presentation: A 10-year-old boy who developed a cough with chest tightness, shortness of breath, hemoptysis with reduced left ventricular ejection fraction, PH, and increased C-reactive protein and erythrocyte sedimentation rate was hospitalized at the pediatric intensive care unit of our hospital. He had strongly positive purified protein derivative skin test and interferon-gamma release assay result. Computed tomography angiography (CTA) showed occlusion of proximal left subclavian artery and stenosis of descending aorta and upper abdominal aorta. His condition did not improve after administration of milrinone, diuretics, antihypertensive agents, and intravenous methylprednisolone pulse followed by oral prednisone. Intravenous tocilizumab was administered for five doses, followed by two doses of infliximab, but his HF worsened, and CTA on day 77 showed complete occlusion of the descending aorta with large thrombus. He had a seizure on day 99 with deterioration of renal function. Balloon angioplasty and catheter-directed thrombolysis were performed on day 127. Unfortunately, the child's heart function continued to deteriorate and died on day 133. Conclusion: TB infection may be related to juvenile TA. The biologics, thrombolysis, and surgical intervention failed to achieve the anticipated effect in our case with aggressive AHF due to severe aortic stenosis and thrombosis. More studies are needed to determine the role of biologics and surgery in such dire cases.

Short-term effectiveness of baricitinib in children with refractory and/or severe juvenile dermatomyositis.

Objective: To determine the short-term effectiveness safety of baricitinib in children with refractory and/or severe juvenile dermatomyositis (rsJDM) in a real-world setting. Methods: This was a single-center retrospective study, including 20 children with rsJDM. They were all treated using baricitinib combined with steroids and other immunosuppressive agents. The childhood myositis assessment scale (CMAS) and PRINTO remission criteria were used to evaluate the disease severity and treatment outcome at 0, 4, 12, and 24 weeks after initiation of baricitinib. Results: The skin rash improved in 95% of patients (19/20) at week 24, with a significant decrease of skin-DAS at weeks 12 (6.0 vs. 2.0, p < 0.05] and week 24 [6.0 vs. 1.0, p < 0.05) by median statistics. The CMAS score increased significantly at week 12 (41.0 [29.0, 44.0] vs. 46.0 [42.0, 52.0], p < 0.05) and week 24 (41.0 [29.0, 44.0] vs. 50.0 [45.0, 52.0], p < 0.05), as did the manual muscle testing (MMT)-8 score at week 24 (73.0 [610, 76.0] vs. 79.0 [77.0, 80.0], p < 0.05). At 24 weeks, the complete response (CR) and partial response (PR) were achieved in 75% (15/20) and 15% (3/20), respectively. The dose of corticosteroids (CS) decreased by 37% from the baseline (0.53 [0.42, 1.00] mg/kg) to week 12 (0.33 [0.18, 0.40] mg/kg) (p < 0.05), and by 49% at week 24 (p < 0.05). No serious side effects were observed. Conclusion: Baricitinib combined with traditional immunosuppressants treatment was efficacious in rsJDM. Add-on therapy of baricitinib was helpful for tapering CS dose. No serious side effects were observed in this study.

Telemedicine management of type 2 diabetes mellitus in obese and overweight young and middle-aged patients during COVID-19 outbreak: A single-center, prospective, randomized control study.

OBJECTIVE: The coronavirus disease-2019 (COVID-19) pandemic severely affected the disease management of patients with chronic illnesses such as type 2 diabetes mellitus (T2DM). This study aimed to assess the effect of telemedicine management of diabetes in obese and overweight young and middle-aged patients with T2DM during the COVID-19 pandemic. METHODS: A single-center randomized control study was conducted in 120 obese or overweight (body mass index [BMI] ≥ 24 kg/m2) young and middle-aged patients (aged 18-55 years) with T2DM. Patients were randomly assigned to the intervention (telemedicine) or control (conventional outpatient clinic appointment) group. After baseline assessment, they were home isolated for 21 days, received diet and exercise guidance, underwent glucose monitoring, and followed up for 6 months. Glucose monitoring and Self-Rating Depression Scale (SDS) scores were evaluated at 22 days and at the end of 3 and 6 months. RESULTS: Ninety-nine patients completed the 6-month follow-up (intervention group: n = 52; control group: n = 47). On day 22, the fasting blood glucose (FBG) level of the intervention group was lower than that of the control group (p < 0.05), and the control group's SDS increased significantly compared with the baseline value (p < 0.05). At the end of 3 months, glycated hemoglobin (HbA1c) and FBG levels in the intervention group decreased significantly compared with those in the control group (p < 0.01). At the end of 6 months, the intervention group showed a significant decrease in postprandial blood glucose, triglyceride, and low-density lipoprotein cholesterol levels as well as waist-to-hip ratio compared with the control group (p < 0.05); moreover, the intervention group showed lower SDS scores than the baseline value (p < 0.05). Further, the intervention group showed a significant reduction in BMI compared with the control group at the end of 3 and 6 months (p < 0.01). CONCLUSION: Telemedicine is a beneficial strategy for achieving remotely supervised blood glucose regulation, weight loss, and depression relief in patients with T2DM. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04723550.

Antifungal Peptide P852 Controls Fusarium Wilt in Faba Bean (Viciafaba L.) by Promoting Antioxidant Defense and Isoquinoline Alkaloid, Betaine, and Arginine Biosyntheses.

Green pesticides are highly desirable, as they are environmentally friendly and efficient. In this study, the antifungal peptide P852 was employed to suppress Fusarium wilt in the Faba bean. The disease index and a range of physiological and metabolomic analyses were performed to explore the interactions between P852 and the fungal disease. The incidence and disease index of Fusarium wilt were substantially decreased in diseased Faba beans that were treated with two different concentrations of P852 in both the climate chamber and field trial. For the first time, P852 exhibited potent antifungal effects on Fusarium in an open field condition. To explore the mechanisms that underlie P852's antifungal effects, P852 treatment was found to significantly enhance antioxidant enzyme capacities including guaiacol peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), and the activities of antifungal enzymes including chitinase and ß-1,3-glucanase, as well as plant dry and fresh weights, and chlorophyll content compared to the control group (p ≤ 0.05). Metabolomics analysis of the diseased Faba bean treated with P852 showed changes in the TCA cycle, biological pathways, and many primary and secondary metabolites. The Faba bean treated with a low concentration of P852 (1 µg/mL, IC50) led to upregulated arginine and isoquinoline alkaloid biosynthesis, whereas those treated with a high concentration of P852 (10 µg/mL, MFC) exhibited enhanced betaine and arginine accumulation. Taken together, these findings suggest that P852 induces plant tolerance under Fusarium attack by enhancing the activities of antioxidant and antifungal enzymes, and restoring plant growth and development.

Correlation between tumor markers and type 2 diabetes mellitus complications and their related influencing factors.

BACKGROUND: This study aims to investigate the correlation between type 2 diabetes mellitus (T2DM) and the tumor markers/biochemical parameters of patients, as well as the related factors leading to complications. METHODS: A total of 150 T2DM patients in our hospital were included as the research group, and 80 healthy persons were matched in the normal control group. The levels of tumor markers (CA199, CEA, CA153, CA125, AFP) and body mass index (BMI), waist-to-hip ratio (WHR), blood pressure (BP), fasting plasma glucose (FPG), glycosylated hemoglobin (HbA1c), urine microalbumin (M-ALB), and triglyceride (TG) in the two groups were determined. Based on the complications status of T2DM patients, the patients were further divided into a complication-free group (patients with simple diabetes) and complication group. Univariate analysis was performed between patients with and without complications. RESULTS: The levels of serum CA199, CEA, and CA125 in the study group were significantly higher than those in the normal control group (all P<0.0001), and the levels of BMI, WHR, systolic BP (SBP), diastolic BP (DBP), FPG, HbA1c, M-ALB, and TG in the study group were significantly higher than those in the control group (all P<0.05). Tumor markers CA199, CEA, and CA125 were positively correlated with BMI, WHR, BP, FPG, HbA1c, M-ALB, and TG. Smoking, family history of diabetes, combined hypertension, hyperlipemia, course of disease, CA199, CEA, CA153, CA125, AFP, SBP, DBP, FPG, HbA1c, M-ALB, and TG were the influencing factors of complications in T2DM patients. CONCLUSIONS: Relevant indicators of T2DM patients with complications should be fully evaluated clinically, and long-term follow-up observation should be conducted, so as to reduce the occurrence of complications.

Scutellarin alleviates type 2 diabetes (HFD/low dose STZ)-induced cardiac injury through modulation of oxidative stress, inflammation, apoptosis and fibrosis in mice.

BACKGROUND: Diabetes is a serious global health concern which severely affected public health as well as socio-economic growth worldwide. Scutellarin (SCU), a bioactive flavonoid, is known for its efficacious action against a range of ailments including cardiovascular problems. The present study was conducted to find out possible protective effect and its associated mechanisms of SCU on experimental type 2 diabetes-induced cardiac injury. METHODS: Type 2 diabetes was induced by treating animals with high fat diet for 4 weeks and a single intraperitoneal dose (35 mg/kg body weight) of streptozotocin and diabetic animals received SCU (10 or 20 mg/kg/day) for 6 weeks. RESULTS: Scutellarin attenuated type 2 diabetes-induced hyperglycemia, bodyweight loss, hyperlipidaemia, cardiac functional damage with histopathological alterations and fibrosis. Scutellarin treatment to type 2 diabetic mice ameliorated oxidative stress, inflammatory status and apoptosis in heart. Furthermore, the underlying mechanisms for such mitigation of oxidative stress, inflammation and apoptosis in heart involved modulation of Nrf2/Keap1 pathway, TLR4/MyD88/NF-κB mediated inflammatory pathway and intrinsic (mitochondrial) apoptosis pathway, respectively. CONCLUSIONS: The current findings suggest that SCU is effective in protecting type 2 diabetes-induced cardiac injury by attenuating oxidative stress and inflammatory responses and apoptosis, and it is also worth considering the efficacious potential of SCU to treat diabetic cardiomyopathy patients.

Low-Intensity Pulsed Ultrasound Modulates RhoA/ROCK Signaling of Rat Mandibular Bone Marrow Mesenchymal Stem Cells to Rescue Their Damaged Cytoskeletal Organization and Cell Biological Function Induced by Radiation.

Osteoradionecrosis of the jaw (ORNJ) is an infrequent yet potentially devastating complication of head and neck radiation therapy. Low-intensity pulsed ultrasound (LIPUS) has been widely accepted as a promising method for the successful management of ORNJ, but the mechanism remains unclear. In this study, the effects of LIPUS on cytoskeletal reorganization, cell viability, and osteogenic differentiation capacity of rat mandible-derived bone marrow mesenchymal stem cells (M-BMMSCs) induced by radiation were determined by immunofluorescence staining, CCK-8 cell proliferation assay, quantification of alkaline phosphatase (ALP) activity, alizarin red staining, and real-time RT-PCR, respectively. Moreover, the involvement of the RhoA/ROCK signaling pathway underlying this process was investigated via western blot analysis. We found that radiation induced significant damage to the cytoskeleton, cell viability, and osteogenic differentiation capacity of M-BMMSCs and downregulated their expression of RhoA, ROCK, and vinculin while increasing FAK expression. LIPUS treatment effectively rescued the disordered cytoskeleton and redistributed vinculin. Furthermore, the cell viability and osteogenic differentiation capacity were also significantly recovered. More importantly, it could reverse the aberrant expression of the key molecules induced by radiation. Inhibition of RhoA/ROCK signaling remarkably aggravated the inhibitory effect of radiation and attenuated the therapeutic effect of LIPUS. In the light of these findings, the RhoA/ROCK signaling pathway might be a promising target for modifying the therapeutic effect of LIPUS on osteoradionecrosis.

Effects of a diet with or without physical activity on angiopoietin-like protein 8 concentrations in overweight/obese patients with newly diagnosed type 2 diabetes: a randomized controlled trial.

Angiopoietin-like protein 8 (ANGPTL8) is a newly discovered adipokine plays an important role in energy homoeostasis, obesity and type 2 diabetes (T2D). Although lifestyle modification in obesity and T2D is known to offer metabolic benefits, there is paucity of comprehensive data on change in ANGPTL8. We investigated the effect of lifestyle intervention on ANGPTL8 concentrations. 384 obese/overweight adults with newly diagnosed T2D were randomly assigned (1:1:1) to diet (n = 128), diet + activity (n = 128) or usual care (control, n = 128) groups. All patients received usual care. Besides, the diet group received a calorie-restricted diet aiming for a weight loss of 5-10%. The diet + activity group additionally received a pedometer-based walking program. Primary outcome was change in ANGPTL8 concentration at 6 months. Data were analyzed according to intention-to-treat. From baseline to 6 months, the median ANGPTL8 level changed from 804.38 pg/mL to 792.86 pg/mL in control group. Compared with control, ANGPTL8 decreased with diet (baseline-adjusted between-group difference was -121.00 pg/mL, 95% CI -177.47 to -64.53; p < 0.0001) and diet + activity (-126.16 pg/mL, -181.21 to -71.11; p < 0.0001). There was no greater effect of diet + activity compared with diet (-5.16 pg/mL, -53.63 to 43.31; p = 0.8348). Both effects disappeared after adjusting for change in body fat, but did not differ significantly when adjusting for physical activity. A 6-month intervention inducing weight loss by a calorie-restricted diet or diet + activity, resulted in significant decrease on ANGPTL8 concentration. These effects were established by change in total body fat, and not by change in physical activity.

Effect of low-intensity pulsed ultrasound on the biological behaviors of bone marrow mesenchymal stem cells on titanium with different surface topographies.

The use of low-intensity pulsed ultrasound (LIPUS) is a promising approach to promote osteogenesis. However, few studies have reported the influence of this technique on the osseointegration of endosseous implants, especially regarding different implant topographies. We focused on how the initial interaction between cells and the titanium surface is enhanced by LIPUS and the potential regulatory mechanisms. The bone marrow mesenchymal stem cells (BMSCs) of rats were cultured on two types of titanium surfaces (polished surface, Flat and large grain blast acid etched, SLA) under LIPUS stimulation or control conditions. The cell proliferation on the implant surfaces was significantly promoted by LIPUS, which stimulated the increase in the number of microfilaments, pseudopodia formed and extracellular matrix mineralization nodules compared with those in the control group. The expression of osteogenesis-related genes, including OPN, OCN, BMP-2, ALP, Runx2 and Col-1, were up-regulated on all the surfaces by LIPUS stimulation. Our findings suggest that LIPUS enhances osteoblast differentiation from BMSCs on titanium surfaces. The use of LIPUS might be a potential adjuvant treatment to improve the osseointegration process.

A Simulation of Low and High Cycle Fatigue Failure Effects for Metal Matrix Composites Based on Innovative J2-Flow Elastoplasticity Model.

New elastoplastic J 2 -flow constitutive equations at finite deformations are proposed for the purpose of simulating the fatigue failure behavior for metal matrix composites. A new, direct approach is established in a two-fold sense of unification. Namely, both low and high cycle fatigue failure effects of metal matrix composites may be simultaneously simulated for various cases of the weight percentage of reinforcing particles. Novel results are presented in four respects. First, both the yield condition and the loading-unloading conditions in a usual sense need not be involved but may be automatically incorporated into inherent features of the proposed constitutive equations; second, low-to-high cycle fatigue failure effects may be directly represented by a simple condition for asymptotic loss of the material strength, without involving any additional damage-like variables; third, both high and low cycle fatigue failure effects need not be separately treated but may be automatically derived as model predictions with a unified criterion for critical failure states, without assuming any ad hoc failure criteria; and, finally, explicit expressions for each incorporated model parameter changing with the weight percentage of reinforcing particles may be obtainable directly from appropriate test data. Numerical examples are presented for medium-to-high cycle fatigue failure effects and for complicated duplex effects from low to high cycle fatigue failure effects. Simulation results are in good agreement with experimental data.

Application of IMF screws to assist internal rigid fixation of jaw fractures: our experiences of 168 cases.

Intermaxillary fixation (IMF) screws were first introduced to achieve IMF as a kind of bone borne appliance for jaw fractures in 1989. Because this method can overcome many disadvantages associated with tooth borne appliance, IMF screws have been popularly used for jaw fractures since then. From March 2011 to February 2014, we treated 168 cases with single or multiple jaw fractures by open reduction and a total of 705 IMF screws were intraoperatively applied in all the cases to achieve IMF and maintain dental occlusion as an adjuvant to open reduction. The numbers, implantation sites and complications of IMF screws were retrospectively analyzed. In our experience, we found that IMF screws were important to assist open reduction of jaw fractures but their roles should be objectively assessed and the reliability of open reduction and internal rigid fixation must be emphasized. Much attention should be paid when implanting.

Improvement of ß-cell function ameliorated glycemic variability in patients with newly diagnosed type 2 diabetes after short-term continuous subcutaneous insulin infusion or in combination with sitagliptin treatment: a randomized control trial.

Glycemic variability (GV) has been proposed as contributor to diabetes-related macrovascular complications. This randomized control trial evaluated a new combination therapy with continuous subcutaneous insulin infusion (CSII) plus sitagliptin (CSII + sitagliptin) vs. CSII only in terms of metabolic control, GV and ß-cell function in patients with newly diagnosed type 2 diabetes (T2DM). 217 patients were randomized to two weeks of CSII (n = 108) or CSII + sitagliptin (n = 109) therapy. As a measure of GV, the coefficient of variation (CV) was computed from capillary blood glucose during the first and second week, respectively. ß-cell function before and after treatment was determined with the Insulin Secretion-Sensitivity Index-2 (ISSI-2). Good metabolic controls were established with both therapies. CSII + sitagliptin therapy resulted in greater improvements in CV and ISSI-2 than CSII alone (all P = 0.000). For each group, change in CV was inversely correlated with change in ISSI-2 (r = -0.529, P = 0.000 and r = -0.433, P = 0.000, respectively). The multivariate regression analysis demonstrated that improved ISSI-2 was the only independent contributor to reduced CV in both groups (standardized ß = -0.388, P = 0.004 and standardized ß = -0.472, P = 0.000, respectively). Correction of ß-cell function in newly diagnosed T2DM patients via use of either CSII or CSII + sitagliptin therapy was feasible in controlling GV to prevent secondary complications of T2DM. Moreover, CSII + sitagliptin therapy was superior to CSII monotherapy in terms of GV.

Maxillary aggressive angiomyxoma showing ineffective to radiotherapy: a rare case report and review of literature.

Aggressive angiomyxoma, mostly originating in the female pelvis and peritoneum or in the male analogous sites, is a rare mesenchymal neoplasm characterized with infiltrative growth to adjacent tissue and local recurrence after primary excision. Herein, we report a case of aggressive angiomyxoma of maxilla in a 60-year-old male patient for its rarity. The patient presented with a one-year history of progressively enlarging maxillary mass on left side. Before referred to our hospital, he was given a biopsy and diagnosed as aggressive angiomyxoma by immunohistochemical staining. After that, he underwent 60 Gy radiotherapy. Unfortunately, CT scan showed bigger mass infiltrated to adjacent facial soft tissues and bones compared with that of before radiotherapy. Besides that, he began to suffer with ingravescent headache. The mass was surgically removed and the diagnosis was confirmed by immunohistology in our hospital. As a case of aggressive angiomyxoma occurred in a rare site and experienced an ongoing growth in spite of radiotherapy, its characteristics was discussed with a brief literature review, which may aid further understanding of aggressive angiomyoma.

Melatonin attenuates inflammation of acute pulpitis subjected to dental pulp injury.

Acute pulpitis (AP), one of the most common diseases in the endodontics, usually causes severe pain to the patients, which makes the search for therapeutic target of AP essential in clinic. Toll-like receptor 4 (TLR4) signaling is widely involved in the mechanism of pulp inflammation, while melatonin has been reported to have an inhibition for a various kinds of inflammation. We hereby studied whether melatonin can regulate the expression of TLR4/NF-ĸB signaling in the pulp tissue of AP and in human dental pulp cells (HDPCs). Two left dental pulps of the adult rat were drilled open to establish the AP model, and the serum levels of melatonin and pro-inflammatory cytokines, including interleukin 1ß (IL-1ß), interleukin 18 (IL-18) and tumor necrosis factor α (TNF-α), were assessed at 1, 3 and 5 d post injury. At the same time points, the expression of TLR4 signaling in the pulp was explored by quantitative real-time PCR and immunohistochemistry. The AP rats were administered an abdominal injection of melatonin to assess whether melatonin rescued AP and TLR4/NF-ĸB signaling. Dental pulp injury led to an approximately five-day period acute pulp inflammation and necrosis in the pulp and a significant up-regulation of IL-1ß, IL-18 and TNF-α in the serum. ELISA results showed that the level of melatonin in the serum decreased due to AP, while an abdominal injection of melatonin suppressed the increase in serum cytokines and the percentage of necrosis at the 5 d of the injured pulp. Consistent with the inflammation in AP rats, TLR4, NF-ĸB, TNF-α and IL-1ß in the pulp were increased post AP compared with the baseline expression. And melatonin showed an inhibition on TLR4/NF-ĸB signaling as well as IL-1ß and TNF-α production in the pulp of AP rats. Furthermore, melatonin could also regulate the expression of TLR4/NF-ĸB signaling in LPS-stimulated HDPCs. These data suggested that dental pulp injury induced AP and reduced the serum level of melatonin and that supplementation with melatonin may have a protective effect on AP by modulating TLR4/NF-ĸB signaling in the pulp and in pulp cells.

Simultaneous detection of four common oral Candida species from blood samples by the fluorescence polarization assay.

The genus Candida is both the commensal microbe and the opportunistic pathogen, containing approximately 200 species inhabiting in oral cavity of 53 % of the general population. Candida species can cause the diseases from local mucosal infections to systemic mycoses, even life-threatening infections in immunocompromised individuals. The timely differentiation of Candida species is important for the guidance of clinical medication. Four common Candida species in Chinese population (Candida albicans, Candida tropicalis, Candida glabrata, Candida krusei) were chosen as the targets to develop the rapid screening method in this work. Combined with amplification by asymmetric PCR, this parallel fluorescence polarization (FP) immunoassay is carried out in homogeneous solution phase. The limit of detection of the assay was shown to be 50 copies/mL in blood samples. The evaluation in multicenter manner showed excellent reproducibility and stability. The comparison between DNA sequencing and the FP immunoassay indicated that there was no significant difference between these methods. This molecular strategy-based method is simple, rapid, and feasible for identifying common Candida species and thereby holding great potential in the application of clinical laboratories.

Effects of chronic sleep deprivation on the extracellular signal-regulated kinase pathway in the temporomandibular joint of rats.

OBJECTIVES: To examine the possible involvement and regulatory mechanisms of extracellular signal-regulated kinase (ERK) pathway in the temporomandibular joint (TMJ) of rats subjected to chronic sleep deprivation (CSD). METHODS: Rats were subjected to CSD using the modified multiple platform method (MMPM). The serum levels of corticosterone (CORT) and adrenocorticotropic hormone (ACTH) were tested and histomorphology and ultrastructure of the TMJ were observed. The ERK and phospho-ERK (p-ERK) expression levels were detected by Western blot analysis, and the MMP-1, MMP-3, and MMP-13 expression levels were detected by real-time quantitative polymerase chain reaction (PCR) and Western blotting. RESULTS: The elevated serum CORT and ACTH levels confirmed that the rats were under CSD stress. Hematoxylin and eosin (HE) staining and scanning electron microscopy (SEM) showed pathological alterations in the TMJ following CSD; furthermore, the p-ERK was activated and the mRNA and protein expression levels of MMP-1, MMP-3, and MMP-13 were upregulated after CSD. In the rats administered with the selective ERK inhibitor U0126, decreased tissue destruction was observed. Phospho-ERK activation was visibly blocked and the MMP-1, MMP-3, and MMP-13 mRNA and protein levels were lower than the corresponding levels in the CSD without U0126 group. CONCLUSION: These findings indicate that CSD activates the ERK pathway and upregulates the MMP-1, MMP-3, and MMP-13 mRNA and protein levels in the TMJ of rats. Thus, CSD induces ERK pathway activation and causes pathological alterations in the TMJ. ERK may be associated with TMJ destruction by promoting the expression of MMPs.

Distraction osteogenesis in the dog mandible under 60-Gy irradiation.

OBJECTIVE: The objective of this study was to explore the probability of distraction osteogenesis (DO) in the irradiated dog mandible after 60-Gy irradiation. STUDY DESIGN: Fourteen Chinese dogs were randomly divided into 2 groups. Twelve dogs received a preoperative unilateral irradiation from (60)Co (group R) in the mandible with a total dose of 24.8 Gy in four 6.2-Gy fractions (biologically equivalent to 60 Gy/25 fractions). The other 2 dogs without irradiation served as the control (group C). Bilateral corticotomies were made 6 months after completion of irradiation. Bone distraction was activated at a rate of 0.5 mm twice daily for 10 days after a 1-week latency period, followed by a consolidation phase of 8 weeks. The inferior alveolar nerve (IAN) underwent electrophysiologic analysis. Dog mandibles were subsequently subjected to histologic and radiographic analysis. RESULTS: All the animals had successful distractions. After 8 weeks of consolidation, no difference was found between the percentage area of new bone in both groups. New bone was more mature and organized in group C than in group R. The action potential of IAN showed corresponding alternation during the irradiation and distraction process. CONCLUSIONS: Based on this study it seems that DO may be feasible in dog mandible under 60-Gy irradiation. Further research is indicated.

A new model of blast injury from a spherical explosive and its special wound in the maxillofacial region.

OBJECTIVE: The goal of this study was to establish an efficient explosive model with spherical explosives for the study of blast injury and its wound characteristics in the maxillofacial region. METHODS: Different spherical explosives were used to produce blast waves and to establish the wound model. Fresh sheep heads as the targets were used for the study of wound characteristics. The wounding parameters and the injuries of targets after explosion were observed. RESULTS: The overpressure values of blast waves decreased exponentially along with the increase of distances to explosives and so did the tissue damage. The blast injury is quite different from other injuries and is more serious. A kind of special "split fracture" of the mandibles was found. CONCLUSIONS: The new explosive wound model with spherical explosives can be used for the study of blast injury in the laboratory. The injury manner of blast wave and the local anatomy of tissues resulted in the special wound characteristics.