Clinical Competence ; Dentists ; Humans ; Temporomandibular Joint Disorders

Objective:To investigate the peripheral mechanism by studying the histological changes of masseter muscles using HE stains and substance P(SP) and protein gene product 9.5(PGP9.5) immunohistochemical stains.Methods: Fifteen male Sprague-Dawley were randomly assigned into occlusal interference group(n=12) and control group(n=3).In occlusal interference group,0.4 mm thick crowns were bonded to the rats'first molar of the maxillary.In the control group,rats were anesthetized and mouths were forced open for about 5 min but restorations were not applied.1,5,10,and 21 d after 0.4 mm occlusal alteration treatment,mechanical pain thresholds of bilateral masseter muscles were quantitatively measured by modified electronic anesthesiometer in control group and occlusal interference group.The rats were euthanized by transcardiac perfusion after deep anesthetization at different time points.The paraffin sections of masseter muscles were made and processed for HE,SP,and PGP9.5 immunohistochemical staining.Results: Decreased head withdrawal threshold to mechanical pressure was detected in masseter muscles on both sides following occlusal interference.Histological stains of masseter muscles presented intact following occlusal interference,and no inflammatory cells were observed in both sides.Intensely stained PGP9.5 was observed at 1 d in occlusal interference groups and maintained until the end of the experiment.SP expression was the most obviously increased at 5 d in both sides and gradually decreased to the level of control.Conclusion: Experimental occlusal interference-induced masticatory muscle pain is associated with peripheral sensitization of nociceptive neurons rather than muscle damage and inflammation.

AIM: To establish human lymphocyte cell line secreting monoclonal antibody against Rhesus(D) antigen and analyse the nucleotide and deduced amino acid sequences of a human monoclonal anti-D Fab fragment. METHODS: By using PCR method, the cDNA of human anti-(Rhesus D) antibody(lgM ?)Fab fragment was amplified from an Epstein- Barr-virus-transformed cell line. Cloning and subsequent sequence analysis of the Fab fragment was performed. The deduced amino acid sequence was compared and analysed with previously published sequences. RESULTS : A band of approximate 700 and 650 base pairs was amplified using lgM heavy chain primers and ? light chain primers, respectively. Sequence analysis indicated that the deduced amino acid sequences was in agreement with the characterization of the amino acid present in the human lg Fab fragment. CONCLUSION: The cloning and sequencing of a human anti-Rhesus (D) antibody Fab fragment cDNA will make benefits for production of recombinant anti-Rhesus (D) antibody and prevention of Rh haemolytic disease in the newborn.

Objective Study on producing human monoclonal antibodies against Rhesus (D) antigen that was suitable for use as blood group typing reagent. Methods B lymphocytes from a Rh negative woman, which can produce anti D antibodies were transformed by Epstein Barr virus(EBV). Antibody secreting cells were enriched by RhD + group O erythrocytes and cloned by limited dilute method. By using one step emzymatic method on microplates, one thousand normal blood donors with a common Rh phenotype were tested with the supernatant of cell culture medium as well as a polyclonal human anti D and a commercial monoclonal anti D serum. Results Three human B lymphocyte lines secreting monoclonal antibodies to Rh (D) were established. One of them produced lgM antibody. The titer of the monoclonal antibodies was 64～128. Study on 1000 blood donors, the results did not show any discrepancy among the three different anti Rh(D) serum. Conclusion These monoclonal antibodies against D antigen could be used in Rh(D) typing.

Objective:To investigate the effect of segmental Le FortⅠosteotomy and bilateral sagittal split ramus osteotomy ( BSSRO ) on the condyle position in skeletal class Ⅲ malocclusion patients . Methods:In this retrospective study , 19 patients with skeletal class Ⅲmalocclusion who met the inclu-sion criteria were enrolled .All the patients underwent the segmental Le FortⅠ osteotomy and BSSRO . Cone beam computed tomography ( CBCT) scans were performed in the following phases:T1:within one week before the surgeries;T2:within one week post-surgery;T3:three months post-surgery;T4:6 to 14 months post-surgery .The posterior spaces , anterior spaces and the superior spaces of the bilateral tem-poromandibular joints were measured according to the Kamelchuk method respectively .The fossa ratios of the condyle and the distribution of the condyle positions related to the glenoid fossa ( anterior , concentric and posterior position ) were calculated .The results were analyzed statistically .Results:The posterior space , the anterior space and the superior space of bilateral temporomandibular joints in T 2 phase [ right:(2.78 ±1.23) mm, (2.47 ±0.89) mm, (3.07 ±0.85) mm; left: (2.93 ±0.83) mm, (2.69 ± 1.14) mm, (3.44 ±1.16) mm] showed significantly larger spaces than those in T 1 phase [right:(1.81 ±0.95) mm, (1.65 ±0.55) mm, (2.13 ±0.52) mm;left:(2.12 ±1.05) mm, (1.79 ±0.59) mm, (2.15 ±0.93) mm],in T3 phase [right:(2.08 ±1.25) mm, (1.79 ±0.68) mm, (1.80 ±0.76) mm;left: (2.05 ±0.75) mm, (1.99 ±0.94) mm, (2.14 ±0.71) mm] and in T4 phase [right:(1.94 ±0.77) mm, (1.81 ±0.69) mm, (2.05 ±0.69) mm;left:(1.89 ±0.69) mm, (1.80 ±0.61) mm, (2.19 ±0.75) mm], P<0.05.No significant differences were observed among T 1,T3 and T4 pha-ses in the terms of the joint spaces of both sides ( P >0.05).The fossa ratio and the condyle position related to the glenoid fossa had no significant difference in all the four phases (P>0.05).The results suggested that the condyle moved downward in T 2 phase and changed to the original pre-surgery position in T3 phase, then keot stable in T4 phase.Conclusion:Segmental Le FortⅠ osteotomy and BSSRO caused significant and transient changes of the condyle position in skeletal class Ⅲmalocclusion patients . However , the condyle tended to move back to the original pre-surgery position and might keep stable .

AIM: To clone and express a human monoclonal anti-D Fab fragment in E. coli and make benefits for the expression of the whole immunoglobulin molecules of anti-D. METHODS: The gene of anti-D Fab fragment was cloned into the phagemid vector pComb3. After analyzing by PCR and restriction site analysis, the recombinant was expressed in E. coli and the expressed protein was analyzed by SDS-PAGE and ELISA. RESULTS: The result of SDS-PAGE confirmed that E.coli expressed a 48 kD protein. The ELISA result demonstrated that the cell culture supernatant reacted with Rh+ group O human erythrocytes, but was not recognized by Rh-group O human erythrocytes. CONCLUSION: Expressed Fab fragment has the antigenic specificity for human erythrocytes.

AIM: To amplify from leader peptide region an d obtain human monoclonal anti-D variable region gene with high specificity and affinity, and analyze the nucleotide and deduced amino acid sequences.ME THODS: The total RNA was extracted from an Epstein-Barr-virus-transforme d cell line secreting monoclonal anti- (rhesus D) antibody. The leader region pri mers containing a ribosome recognition site were designed. By using PCR method, the cDNA of human anti-(rhesus D) antibody (IgM ?) variable region gene was amp lified. Cloning and subsequent sequence analysis of the variable region gene was performed. The deduced amino acid sequence was also compared and analyzed with previ ously published sequences.RESULTS: A band of approximate 440 and 410 base pairs were amplified using heavy chain primers and light chain primer s, respectively. Sequence analysis indicated that the deduced amino acid sequenc e w as in agreement with the characterization of the amino acid present in the human Ig variable region. CONCLUSION: The cloning and sequencing of a human anti- (Rhesus D) antibody variable region cDNA will make benefits for pro duction of recombinant anti-(Rhesus D) antibody and prevention of Rh haemolytic disease in newborns.

The graft-versus-tumor (GVT) effect of T cells induced by tumor antigen-pulsed CD8α(+) dendritic cells (DCs) in vitro was investigated in this study. Immature CD8α(+) DCs were prepared from C57BL/6 (H-2(b)) bone marrow cells by using a cytokine cocktail. On the 3rd day of culture, CD8α(+) DCs were pulsed by allogeneic (Balb/c, H-2(d)) EL9611 leukemia antigen, or RM-1 syngeneic prostate cancer antigen, with the concentration series of 0, 2.5, 5.0, 10.0, 20.0 μg/mL, respectively, then antigen-loaded immature CD8α(+) DCs were co-cultured with syngeneic T cells according to the DC/T ratio of 1:1, 2:1 and 4:1. T cell proliferation was measured by MTT assay. Cytokines including interferon gamma (IFN-γ) and interleukin-10 (IL-10) in CD8α(+) DCs and T co-culture supernatant were detected by using ELISA. Cytotoxic effect of antigen-specific T cells was tested by LDH release assay. Conventional mature DCs (mDCs) induced from C57BL/6 (H-2(b)) bone marrow cells by using granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) served as a control. The results showed that the proliferative activity of T cells stimulated by CD8α(+) DCs loaded with allogeneic or syngeneic tumor antigen was augmented with the CD8α(+) DC/T ratio increased (P<0.05). When antigen concentration ≤ 5 μg/mL and CD8α(+) DC/T ratio ≤ 2:1, the ability of CD8α(+) DCs to stimulate T cell proliferation was higher than mDC control in allogeneic tumor antigen-pulsed groups (P<0.05), but not in syngeneic tumor antigen-pulsed groups (P>0.05). The level of IFN-γ and IL-10 in CD8α(+) DCs and T cell co-culture supernatant were increased in both allogeneic and syngeneic antigen-pulsed groups (P<0.05), and the cytokine level was higher in allogeneic antigen-pulsed groups than in syngeneic antigen groups when the CD8α(+) DC/T was 1:1 or 2:1 (P<0.05). There existed a negative correlation between the level of IL-10 and T cell proliferation. T cell cytotoxicity assay showed that when CD8α(+) DCs were pulsed with allogeneic tumor antigen, the maximal T cell killing efficiency could reach (100±7.7)%, whereas syngeneic tumor antigen-pulsed group had only (65.0±3.4)%. It was concluded that syngeneic and allogeneic tumor antigen-pulsed immature CD8α(+) DCs could stimulate T cells to exert the GVT effect in vitro, and the GVT effect was more obvious with allogeneic tumor antigen than with syngeneic tumor antigen. The optimal condition was low allogeneic tumor antigen pulsation (≤ 5 μg/mL) and low CD8α(+) DC/T ratio (1:1 and 2:1).

OBJECTIVE: To study the effects of occlusal trauma on the ultra-structure of synovial membrane and articular cartilage in rabbit's temporomandibular joints (TMJ). METHODS: TMJs from six rabbits with occlusal trauma and three control rabbits were studied by transmission electron microscopy. RESULTS: Degenerative changes in synovial membrane and articular cartilage of TMJ were induced following occlusal trauma. The structure of the articular surface was damaged, and chondrocytes in cartilage showed signs of degeneration. The synovial lining cells contained dense accumulations of vimentin intermediate filaments (IFs), which were especially prevalent in the cellular processes as well as paranuclearly. Microvilli on the synovial cell membrane were commonly seen. The "vermiform bodies" in the deeper interstitium of the synovial tissue were also found. Our findings of the punctate adherens between synovial lining cells were described in detail. CONCLUSIONS: The occlusal trauma is really a factor inducing degenerative changes of the TMJ.

OBJECTIVETo evaluate a new treatment method for temporomandibular joint acute disk displacement without reduction.

METHODSTwenty-one patients diagnosed as acute anterior disk displacement without reduction were treated by manipulation with the aid of joint cavity extension followed by anterior repositioning splint. All and eleven of twenty-one patients were re-examined two weeks after insertion of splint and at the end of treatment (3 approximately 6 months later).

RESULTS(1) Degree of maximum mouth opening was increased from 25.8 mm before treatment to 46.6 mm 2 weeks after, 48.1 mm at the end of treatment; (2) Mean pain level (VAS) dropped from 2.62 before treatment to 0.43 2 weeks after, 0.18 at the end of treatment; (3) Fricton's TMJ dysfunction index and craniomandibular index decreased from 0.337 and 0.185 respectively before treatment to 0.021 and 0.011 respectively 2 weeks after, 0.031 and 0.018 respectively at the end of treatment.

CONCLUSIONSThe treatment method should be considered for acute anterior disk displacement without reduction if medication and physical therapy failed to have disk successfully reduced.

Acute Disease ; Adolescent ; Adult ; Female ; Humans ; Joint Dislocations ; therapy ; Male ; Manipulation, Orthopedic ; Splints ; Temporomandibular Joint Disorders ; therapy