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Xu-chen Ma

Publications and source records attributed to Xu-chen Ma.

14 recordsLinked to original sources
PubMed2006

[Analysis of the mitochondrial mutations of articular chondrocyte in temporomandibular joint osteoarthrosis].

OBJECTIVE: To explore the significance of mitochondrial DNA mutations of articular chondrocytes in the rat model of temporomandibular joint osteoarthrosis (TMJOA). METHODS: TMJOA models were created in left sides of TMJ of 15 SD rats by the partial resection of the articular disc. The experimental rats were killed 3 months after operation. After the chondrocytes culture, the entire mtDNA were amplified using 32 pairs of overlapping. DNA fragments showing different banding patterns between normal and experimental mtDNA by temporal temperature gradient gel electrophoresis were sequenced to identify the mutations. RESULTS: Of the 35 heteroplasmic pattern PCR products, 42 novel mutations were found, Majority of the novel mutations were in the tRNA and D-loop regions. CONCLUSION: The mutations occurred in the mtDNA of TMJOA articular chondrocytes.

Animals↗
PubMed2006

[Brain activities during maximum voluntary clenching with and without soft splint in patients with hemimasticatory spasms by functional magnetic resonance imaging].

OBJECTIVE: Functional magnetic resonance imaging (fMRI) was used to detect the cerebral cortical somatotopy during maximum voluntary clenching with and without soft splint in patients with hemimasticatory spasms (HMS) and the central mechanisms of HMS and the rule of the splint therapy. METHODS: Four HMS patients were selected and the spasms sides were right in two cases and left in the other two cases. FMRI images were obtained on Elscint/GE 2.0 Tesla MR system. Block design was used and the movement pattern was the onset of spasms after maximum voluntary clenching with and without soft splint. The fMRI data were analyzed by SPM99 software. RESULTS: With the onset of spasms after maximum voluntary clenching, the activation of motor cortex in 3 HMS patients was found lateral dominance on the left side, and the other one showed bilateral activation. All the 4 patients were found activation in cingulate area. With the onset of spasms after maximum clenching wearing soft splints, the activation of motor cortex showed no lateral dominance on the left side, and 3 patients were not found activation in cingulate area. CONCLUSIONS: The changes of the activation in motor cortex and cingulate area during the onset of spasms after clenching with and without soft splint might be the central mechanisms of the rule of splint therapy, through which the soft splint might function in alleviating muscle pain.

Brain↗
PubMed2005

Clinical study of preoperative angiography and embolization of hypervascular neoplasms in the oral and maxillofacial region.

OBJECTIVE: The purpose of this study was to investigate the angiographic features of hypervascular head and neck neoplasms and to evaluate the effects of embolization on these lesions. METHODS: Angiograms and operation records of 25 patients with hypervascular neoplasms (23 neck paragangliomas, 1 hemangiopericytoma, and 1 hemangioendothelioma) were retrospectively analyzed, and the effects of 8 embolization procedures were estimated. RESULTS: Angiograms demonstrated that 23 neck paragangliomas (NPs) were manifested as richly vascularized lesions, and were divided into 3 types. Type I NPs (n = 2) were located cranial-laterally to the carotid bifurcation, and were removed with an intact carotid artery and injured vagus nerve. Type II (n = 17) lesions widened the bifurcations in 16 of 17 cases. During the operation, the continuity of the internal carotid arteries was preserved in 15 of 17 cases. Type III (n = 4) lesions enveloped the carotid bifurcations, and were removed together with the bifurcations in 3 of 4 cases. In 6 type II paraganglioma cases intra-arterial embolization was employed and the paragangliomas were removed with less blood loss (238 mL) than the nonembolized group (600 mL). Additionally, the infratemporal hemangiopericytoma and the parotid hemangioendothelioma were embolized and removed uneventfully. CONCLUSIONS: Angiographic studies are highly valuable for the diagnosis and preoperative analysis of hypervascular head and neck neoplasms. Also, embolization therapy may minimize intraoperative blood loss. Both methods should be employed in a team approach to lesion treatment.

Adolescent↗
PubMed2005

A preliminary study of angiographic classification and its correlation to treatment of central arteriovenous malformation in the jaw.

OBJECTIVE: To elaborate on the classification of central arteriovenous malformations (AVMs) in the jaw based on angioarchitecture and to evaluate the correlation of this classification with treatment options. STUDY DESIGN: X-ray films and digital subtraction angiograms (DSA) of 25 cases with AVMs in the jaw were retrospectively reviewed to evaluate the appearance of bone resorption, feeding arteries, nidus of the malformations, and draining veins. Based on the findings a classification of angioarchitecture was recommended. Furthermore, the treatment results of these cases were reviewed to assess the correlation of this classification system with treatment options. RESULTS: The angiographic pictures of 25 cases with central AVMs could be divided into 5 types: Type I (n = 5) had diffused microarteriovenous fistulas (AVFs); type II (n = 8) had 1 large venous pouch with all the feeding arteries draining into it; type III (n = 7) had a large venous pouch as well as diffused microAVFs (I+II); type IV (n = 2) had multiple venous pouches; and type V (n = 3) had multiple venous pouches and diffused microAVFs (I + IV). The angioarchitecture corresponded well to the x-ray appearance in all cases except 1 (96%). With respect to the treatment outcomes, type II, III, and IV AVMs gained clinical cure in 100% of the cases, whereas type I and type V AVMs obtained clinical cure only in 60% and 33.3% of the cases, respectively. CONCLUSIONS: Central AVMs in the jaw contained variant patterns of angioarchitecture and could be divided into 5 types. This angiographic classification was helpful for decision making about appropriate therapy.

Adolescent↗
PubMed2005

[Brain activities during maximum voluntary clenching with soft occlusal pad in healthy adults by functional magnetic resonance imaging].

OBJECTIVE: Using functional magnetic resonance imaging (fMRI) to detect the cerebral cortical somatotopy during maximum voluntary clenching with soft occlusal pad in healthy adults. By comparing with the cerebral cortical activation during clenching with and without soft occlusal pad we try to detect the central mechanism of the rule of the occlusal pad. METHODS: Ten healthy subjects were selected and scanned by Elscint/GE 2.0 Tesla MR system. Block design was used and the movement pattern was maximum voluntary clenching with soft occlusal pad. The fMRI data were analyzed by SPM99 software and group map analysis was done. RESULTS: The activation areas were found in bilateral or unilateral motor cortex, somatosensory cortex, prefrontal cortex, temporal cortex, premotor cortex, insula, frontal operculum, basal ganglia (putamen), parietal cortex and cingulate. Group map analysis showed activation in bilateral motor cortex, right somatosensory cortex, bilateral basal ganglia, and bilateral insula. The activation of left motor cortex was significantly higher than right side. Compared with cortical activation without occlusal pad, the motor and somatosensory cortex changed a lot. CONCLUSION: The changes of the activation of motor and somatosensory cortex during clenching after wearing the soft occlusal pad might be the central mechanism of the rule of the occlusal pad.

Adult↗
PubMed2005

[A preliminary study of angiographic classification and treatment of central arteriovenous malformations in jaws].

OBJECTIVE: To elaborate on the angiographic classification of central arteriovenous malformations (AVMs) in jaws, and to evaluate the correlation between this classification and treatment options. METHODS: X-ray films and angiograms of 25 cases with AVMs in the jaw were retrospectively reviewed to evaluate the appearance of radiolucency, feeding arteries, nidus of the malformations and draining veins. Based on the findings a classification of angioarchitecture was recommended. Furthermore, the treatment results of these cases were reviewed to assess the correlation between this classification and treatment options. RESULTS: The angiographic pictures of 25 cases with central AVMs could be divided into five types: type I (n = 5) was with merely diffused micro-arteriovenous fistulas (AVFs); type II (n = 8) demonstrated a large venous pouch, all the feeding arteries drained into it; type III (n = 7) had a large venous pouch together with diffused micro-AVFs (I + II); type IV (n = 2) had multiple venous pouches; type V (n = 3) had multiple venous pouches and diffused micro-AVFs (I + IV). The angioarchitecture corresponded well to the radiographic appearance in all except one case. With respect to the treatment, type II, III, IV AVMs gained clinical cure in 100% of cases, whereas type I and type V AVMs obtained clinical cure only in 3 of 5 and 1 of 3 cases respectively. CONCLUSIONS: Central AVMs in jaws exhibited variant patterns of angioarchitecture, which could be divided into five types. Elaboration of this classification was helpful for decision-making on choosing appropriate therapy.

Adolescent↗
PubMed2004

[Hemimasticatory muscle spasm: an electromyogram analysis].

OBJECTIVE: To investigate the usefulness of electromyogram (EMG) in the diagnosis of the patients with hemimasticatory spasm (HMS). METHODS: Four cases with HMS were reported. All the 4 patients were undertaken needle and surface electrode EMG examination. RESULTS: Needle electrode EMG of the 4 patients with HMS showed grouped potentials synchronously with the onset of the spasm, which indicated abnormal excitatory electrical activities of the trigeminal nerve resulting in involuntary masticatory muscle movements. CONCLUSION: It is very important to use EMG for the diagnosis of HMS.

Adult↗
PubMed2004

[Study on the metabolism of cartilage matrix by the chondrocytes in osteoarthritic condylar cartilage].

OBJECTIVE: To study the characteristics of cellular metabolism of mandibular condylar chondrocytes in repairing state of osteoarthrosis and investigate its role in the pathogenesis of the disease. METHODS: Temporomandibular joint osteoarthrosis model of rabbits was created by the partial resection of joint disc and confirmed with histological diagnosis. The chondrocytes were harvested from osteoarthritic condylar cartilage in the repairing state and cultured in vitro under the monolayer culture condition. The cellular expression of cartilaginous matrix protein, collagenase and growth factors between the osteoarthritic chondrocytes and the normal controls were measured with RT-PCR technique to outline the basic feature of the osteoarthritic cells. RESULTS: The cultured cells were confirmed as chondrocytes with their ability of expression of collagen type II and Aggrecan. In the reactive repairing state of osteoarthrosis, the chondrocytes showed the imbalance of expression of ECM proteins, and increased expression of collagenase and endogenous growth factors such as IGF-1 and TGF-beta1. CONCLUSIONS: This study found the active anabolism of the chondrocytes within the osteoarthritic condylar cartilage and the imbalance synthesis of cartilage matrix. These repairing attempts by the osteoarthritic chondrocytes may be impossible to restore the primary homeostasis within the condylar cartilage.

Animals↗
PubMed2004

[Study on the characteristics of apoptosis in the condyles of osteoarthritic temporomandibular joints].

OBJECTIVE: To study the characteristics of apoptosis in the condyles of osteoarthritic temporomandibular joints, and investigate its role in the pathogenesis of the disease. METHODS: Temporomandibular joint osteoarthrosis model of rabbits was created by partial resection of joint disc. The animal models were sacrificed in the 15th day, the 1st month, the 2nd month, the 3rd month, the 4th month, the 5th month, and the 6th month chronologically. Then the pathological condyles were sectioned and detected with TUNEL method to investigate the apoptosis within the tissue. RESULTS: In the reactive repairing state of osteoarthrosis, the apoptosis cells mainly located in the superficial fibrous layer of articular cartilage. With the remodeling of articular cartilage and bone, the apoptosis cells gradually appeared in the proliferating layer, especially in the "clusters of chondrocytes". Accompanied with the severe damage and loss of articular cartilage, the phenomena of apoptosis decreased in the lower zone of cartilage and increased in the hypertrophic and calcified zone. CONCLUSION: There were abundant phenomena of apoptosis within the condylar cartilage of osteoarthritic temporomandibular joint. Abnormal proliferation and abundant apoptosis would disturb the regulation mechanism in the cartilage matrix and lead to the osteoarthrosis.

Animals↗
PubMed2003

[Temporomandibular joint disc displacement: diagnosis by arthrography with dental volumetric computerized tomography].

OBJECTIVE: Temporomandibular joint sideways and rotational disc displacement was assessed by arthrography with dental volumetric computerized tomography. METHODS: The study was conducted retrospectively on 119 joints of 109 patients (87 females, 22 males, mean age 31.1 years), who had undergone arthrography with dental volumetric CT in the sagittal and coronal planes. The disc displacements were subdivided into 5 types; condylar abnormalities were subdivided into 4 types. RESULTS: Complete anterior disc displacement was the commonest (70.6%) and medial the rarest (0.8%); anterolateral and anteromedial displacements were 18.5% and 10.1% respectively. The types of disc displacements were not correlated with bone lesions. A higher prevalences of bone lesions were found in the lateral poles of condyles. CONCLUSIONS: Arthrography using dental volume CT can be taken in the sagittal and coronal planes, so the sideways and rotational disc displacements, perforations and bone lesions can be evaluated. It's superior to conventional arthrography.

Adolescent↗
PubMed2002

Color Doppler sonography of the facial artery in the anterior face.

OBJECTIVES: The purpose of this study was to clarify the Doppler sonographic features of the facial artery in the anterior face in healthy volunteers and to investigate those of related hemangiomas. STUDY DESIGN: Forty-six volunteers and 3 patients with hemangiomas were examined with Doppler sonography. The detection rates of the facial artery in the anterior face were determined. The features of the main trunk, superior and inferior labial branches, and the branches in the buccinator area were investigated together with the flow diameter, flow velocities, and resistive and pulsatility indexes. RESULTS: The detection rates of the main trunk and superior and inferior branches were 100%, whereas that of the branches in the buccinator area was 92.4%. There were no significant differences in the measured values for all indexes between the right and left sides. However, there were significant correlations between right and left sides in the flow diameter and minimum velocity of the main trunk and in the flow diameter and pulsatility index of the superior labial branch. The Doppler sonographic features of the hemangioma were characterized as a hypoechoic area with internal and surrounding blood flows. CONCLUSIONS: Doppler sonography can clearly depict the facial artery and its branches in the anterior face, and this method appears to be useful in the follow-up examination of hemangiomas in this area.

Adult↗