BACKGROUND:Using Twin-block appliance to treat mandibular retrusion,the mandible position changes greatly.The influence of this change on temporomadibular joint and the effect of Twin-block appliance on condylar growth remain unclear.OBJECTIVE:To observe the effect of Twin-block appliance on condylar process location during mandible forward positioning.PARTICIPANTS:A total of 20 patients with mandible retraction (Angel Ⅱ) malocclusion were selected from Department of Stomatology,First Sanatorium of Qingdao,Jinan Military Area Command of Chinese PLA,comprising 13 males and 7 females,aged 10.8 years (range 9-13 years).All patients were treated with Twin-block appliance.Four median joint pantomograms were taken before treatment,1 week after treatment,1 week and 1 year after treatment finish to measure the condylar process location.RESULTS AND CONCLUSION:In all cases,neutroclusion were obtained.No clicking,pain or other temporomadibular joint symptoms were observed.The condylar process position altered significantly.The anterior space distance was decreased,the superior space distance was increased,and posterior space was enlarged (P<0.05-0.01),i.e.condylar process moved downward and forward.The condylar process position was consistent with preoperative,and joint superior,anterior and posterior space distributed balancedly.Twin-block appliance could restore normal and harmonious process-fossa relationship through growth remodeling,but maintenance is necessary till the remodeling accomplish.

BACKGROUND: The initial stability of implantable distractor depends on the stress distribution of bone-distractor interface. The understanding of the biomechanical change in initial stage can improve the clinical success ratio of implantable distractor used in alveolar crest.OBJECTIVE: To evaluate the influence of bone quality on stress distribution and deformation in initial distraction stage.METHODS: Four three-dimensional models with 10 079-11 456 cells and 17 299-20 101 nodes were prepared by finite element methods (11 mm in length and 3.7-4.1 mm diameter). Implantable distractor was embedded in a segment of mandible. The elastic modulus of cancellous bone and the thickness of cortical bone, stress and deformation of bones and distractor were calculated.RESULTS AND CONCLUSION: The highest stress in the bone was concentrated in transportable section and the maximum deformation of transportable section was observed at the edge of the cortical bone, both of which were increased with bone quality decreased. The subsidence of distractor was observed with bone quality decreased. Bone quality influenced the initial stability and the result of the implantal distraction. The decrease of bone elastic modulus would increase the failure risk of distraction osteogenisis.

Objective:To evaluate the effects of magnetron-sputtered ZrSiN/ZrO2 gradient coating on the bonding strength of commercially pure titanium to porcelain.Methods:50 cast titanium specimens were prepared according to the ISO 9693 standard,and divided into 2 groups(n =25).The ZrSiN/ZrO2 gradient coating was deposited on specimens by magnetron sputtering technique,and subsequently a low-fusing porcelain was applied for the samples in the expermental group,the samples in the control group were treated by surface sandblasting.The roughness and surface energy of the samples were measured(n =10).The bonding strength of titanium-porcelain specimens was analyzed by three-point bending test (n =10).Scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDS) were employed to examine the properties of the delaminated and cross-sectioned surfaces.The results were analyzed by paired t-test (α =0.05) with SPSS 1 1.0 software.Results:The roughness of the experimantal group was lower(P ＜ 0.05) and the contact angle was larger(P ＜ 0.05) than those in the control group.The titanium-porcelain bond strength of gradient-coated group was greater than that of control group(P ＜0.05).The SEM and EDS examination results of delaminated and cross-sectioned surfaces also indicated that the gradient-coated group showed more porcelain residues.Conclusion:The bonding strength of porcelain-fused-to-titanium can be improved by magnetron sputtered ZrSiN/ZrO2 gradient coating.

BACKGROUND: Because of complicated physiological environment and difficulty to control experimental conditions, it is difficult to get satisfactory results from in vivo studies of cell mechanics.OBJECTIVE: To study the action and mechanism of p38MAPK signaling pathways on myoblast apoptosis based on successful construction of in vitro mechanical stimulation models.METHODS: The C2C12 cells cultured in vitro were divided into control group and SB203580 treatment group. Cyclic tensile stress was applied on the C2C12 myoblast cells for 0, 6, 12 and 24 hours in each group. The Flexcell Strain Unit-5000T was used to expose C2C12 myoblast cell to an equiaxial cyclic of 15% magnitude and a frequency of 10 cycles/min, each cycle including the 3 s stretch and 3 s relaxation. Hoechst 33258 fluorescent staining and optical microscope were used to detect cell apoptosis. RT-PCR, flow cytometric analysis were used to observe the apoptosis of C2C12 myoblast cells and Western blotting were used to detect the activity of p38MAPK and p-p38MAPK. RESULTS AND CONCLUSION: The optical microscope tested the change in the morphology. Hoechst 33258 staining showed that after treatment with cyclic stress, the cell took the typical appearance of apoptosis with chromatin condensation and apoptotic bodies. RT-PCR and flow cytometry showed that with the extension of time the rate of the apoptosis of C2C12 myoblast cell increased. And cells imposed SB203580 before imposing cyclical tensile stress, the results showed that the apoptosis was markedly affected, and the p-p38MAPK expression declined apparently. These findings demonstrate that p38MAPK signaling pathways in stress mediated into C2C12 myoblast cell apoptosis plays an important role.

OBJECTIVEThe color difference meter and electronic nose fingerprint analyzer were introduced to discriminate processed betel nut's different huohou and quantize empirical index during the processing of Chinese medicine.

METHODBy collecting the color's and the smell's characteristic parameters of betel nut and its processed products to set up huohou's math discrimination modules and 90% reference value scale.

RESULTWe set up a huohou's math discrimination module and 90% reference value range base on L a*b*, which discrimination coincidence was 100% and 90% reference value range respectively was Shengpin: L* (50.07-55.03), a* (4.136-6.906), b* (6.65-8.82); Chaopin: L* (43.874-47.998), a* (3.816-6.732), b* (3.786-6.558); Jiaopin: L* (38.744-40.616), a* (1.11-3.01), b* (-1.434-0.538). At the same time, we set up a huohou's math discrimination module base on smell's characteristic parameters too.

CONCLUSIONThe betel nut and its processed products' color and smell measurement based on the color difference meter and electronic nose fingerprint analyzer may be feasible, and provides a reference to better study on traditional Chinese medicine theory.

Areca ; chemistry ; Pigmentation ; Technology, Pharmaceutical ; methods

Objective:To explore the coexisting gene mutations of FLT3-ITD mutation and its association with partial clinical parameters in acute myeloid leukemia (AML).Methods:The clinical data of 236 newly diagnosed AML outpatients and hospitalized patients of Changzhou No.2 People's Hospital and the Second People's Hospital of Wuxi between December 2012 and August 2019 were retrospectively analyzed. Genome DNA-polymerase chain reaction (PCR) combined with Sanger sequencing was used to detect FLT3-ITD mutations, and 51 tumor target gene mutations in patients with FLT3-ITD mutations were detected by using high-throughput DNA sequencing combined with Sanger sequencing.Results:Among 236 AML patients, FLT3-ITD mutations were found in 71 cases (30.1%). About 97.2% (69/71) patients with FLT3-ITD mutations were accompanied by additional mutations, of which 19 patients harbored double coexisting genes mutations, 24 patients harbored 3 coexisting genes mutations and 26 patients harbored ≥ 4 coexisting genes mutations. The most common coexisting genes mutations were NPM1 (55 cases, 77.5%), followed by DNMT3A (36 cases, 50.7%), TET2 (9 cases, 12.7%), CEBPA (5 cases, 7.0%), IDH1 (4 cases, 5.6%) and NRAS (4 cases, 5.6%). In FLT3-ITD mutation group, the hemoglobin level of patients with DNMT3A mutation type was lower than that of those with DNMT3A wild type ( t = -2.37, P = 0.020); the hemoglobin level of patients with NPM1 mutation type was higher than that of those with NPM1 wild type ( t = 2.04, P = 0.045). The platelet in patients with 3 mutations and ≥ 4 mutations was higher than that in those with double mutations ( χ2 = 7.72, P = 0.021). After chemotherapy in 71 patients, the curative effect of 66 cases was evaluable, and the white blood count of 18 patients who did not reach complete remission was higher than that of 48 patients who reached complete remission ( Z = -2.74, P = 0.006). Conclusions:Most FLT3-ITD mutated patients with AML commonly show coexisting gene mutations, and the mutation types of coexisting genes are correlated with the clinical features of patients.

OBJECTIVETo explore the mechanism of NK cell dysfunction in patients with multiple myeloma (MM).

METHODSThe expression of inhibitory receptors (CD158a and CD158b) and activating receptors NKG2D and NCRs (NKp30, NKp44 and NKp46) on CD3-CD56+NK cell of 13 MM patients and 30 healthy controls were analyzed by flow cytometry. The concentration of soluble NKG2D ligands (MICA, MICB, ULBP1, ULBP2 and ULBP3) in serum was detected by enzyme- linked immunosorbent assay (ELISA), and the cytotoxicity of NK cell against MM cell line by flow cytometry.

RESULTSThere are no significant differences of percentage and absolute number of NK cells, and the expression level of CD158a and CD158b between MM patients and healthy individuals (P>0.05). No NKp44 expression was detected on fresh isolated NK cells from both groups. There is no difference in inhibitor receptors expression between MM patients and healthy individuals but the expression of NKG2D, NKp30 and NKp46 on NK cells were higher in MM patients as compared with that in healthy individuals. The concentration of soluble NKG2D ligands in serum was higher in MM patients as compared with that in healthy individuals (P<0.05). Cultured healthy individual's NK cells with MM patient's serum could significantly decrease its cytotoxicity against MM cell line U266 cells [(38.5 ± 6.5) % vs (25.4 ± 5.9)%, P=0.044］.

CONCLUSIONThe higher level of soluble NKG2D ligands in serum may be the mechanism of NK cell dysfunction in MM patient.

Cells, Cultured ; Flow Cytometry ; Humans ; Killer Cells, Natural ; metabolism ; pathology ; Multiple Myeloma ; immunology ; metabolism ; NK Cell Lectin-Like Receptor Subfamily K ; metabolism ; Natural Cytotoxicity Triggering Receptor 1 ; metabolism ; Natural Cytotoxicity Triggering Receptor 2 ; metabolism ; Natural Cytotoxicity Triggering Receptor 3 ; metabolism ; Receptors, KIR2DL1 ; metabolism ; Receptors, KIR2DL3 ; metabolism