Wei Sun

Publications (3)4.41 Total impact

• Article: Bacterial diversity in synovial fluids of patients with TMD determined by cloning and sequencing analysis of the 16S ribosomal RNA gene.

  Wei Sun, Lingli Dong, Keiseki Kaneyama, Tsutomu Takegami, Natsuki Segami
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  ABSTRACT: The purpose of this study was to examine the presence of bacteria in synovial fluids from patients with temporomandibular joint disorder (TMD) by polymerase chain reaction (PCR) targeting the 16S ribosomal RNA (rRNA) gene, followed by cloning and sequencing. Universal bacterial primers were used to amplify 16S rRNA genes in 28 synovial fluid samples from 27 patients with TMD (TMD group) as well as control subjects: 5 patients with dislocation of TMJ (non-TMD group). Subsequently, PCR amplicons were purified and cloned. Partial 16S rRNA sequences of the cloned insert were used to determine the species identities or closest relative by comparison with known sequences using GeneBank. Nineteen (67.86%) of 28 samples from patients in the TMD group were identified with the presence of bacterial DNA by PCR. The 5 control samples from the nonTMD group were all negative in this study. After cloning and sequencing, a total of 11 bacterial species was detected, including Granulicatella adiacen (6 samples), Pseudomonas sp. (6 samples), Methylobacterium sp. (5 samples), and Beta proteobacterium (4 samples). Other species, such as Acidovorax sp., Bradyrhizobium sp., Sphingomonas, Streptococcus, Leptothrix sp. oral clone, Thiobacillus denitrificans, and Comamonadaceae bacterium, were also identified. Eight patients were found with mixed bacteria, with 2-4 bacteria per sample. The patients with fastidious bacteria such as Granulicatella adiacen and mixed bacteria were more likely to be older than 45 years (P < .05). A wide variety of bacteria, including some not previously reported associated with TMD, were identified in the synovial fluids from patients with TMD.
  Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 06/2008; 105(5):566-71. · 1.50 Impact Factor
• Article: Levels of soluble cytokine factors in temporomandibular joint effusions seen on magnetic resonance images.

  Keiseki Kaneyama, Natsuki Segami, Wei Sun, Jun Sato, Kazuma Fujimura
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  ABSTRACT: To elucidate the correlations between joint effusion (JE) on T2-weighted magnetic resonance images (MRI) of the temporomandibular joint (TMJ) and the levels of various cytokine receptors, cytokine antagonists, and protein in the synovial fluid of patients with temporomandibular joint disorders (TMD). Fifty-five TMJs of 55 patients with TMD were scanned by MRI, and synovial fluid samples were obtained on the same day. The grade of JE was evaluated on a scale of 0 to 3: Grades 0 and 1 indicated absence, and grades 2 and 3 indicated the presence of JE. Correlations were evaluated between JE and the concentrations of soluble tumor necrosis factor receptors I and II (sTNFR-I and sTNFR-II, respectively), IL-6 soluble receptor (IL-6sR), IL-1 soluble receptor type II, and IL-1 receptor antagonist and protein in the synovial fluid of patients with TMD. The concentrations of sTNFR-I and protein in the group with JE (18 joints) were significantly higher than in the group without JE (37 joints). In addition, there were significant positive correlations between the grade of JE and the levels of sTNFR-I, sTNFR-II, and protein. sTNFRs and protein may play important roles in the pathogenesis of TMD. These mediators seem to influence the expression of JE, which may reflect synovial inflammation of the TMJ.
  Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontics 05/2005; 99(4):411-8. · 1.46 Impact Factor
• Article: Analysis of tumor necrosis factor-alpha, interleukin-6, interleukin-1beta, soluble tumor necrosis factor receptors I and II, interleukin-6 soluble receptor, interleukin-1 soluble receptor type II, interleukin-1 receptor antagonist, and protein in the synovial fluid of patients with temporomandibular joint disorders.

  Keiseki Kaneyama, Natsuki Segami, Wei Sun, Jun Sato, Kazuma Fujimura
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  ABSTRACT: To measure the levels of various cytokines, cytokine receptors, and cytokine antagonists in the synovial fluid of patients with temporomandibular disorders (TMD) and to determine the correlations among these expression levels. Synovial fluid was obtained from 55 patients with TMD and from 5 asymptomatic healthy volunteers as controls. The concentrations of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-1beta, soluble tumor necrosis factor receptors I and II (sTNFR-I and sTNFR-II), IL-6 soluble receptor (IL-6sR), IL-1 soluble receptor type II, and IL-1 receptor antagonist were determined by enzyme-linked immunosorbent assay. The concentrations of TNF-alpha, IL-6, IL-1beta, sTNFR-I, and sTNFR-II were significantly higher in the synovial fluid of patients than in controls (P < .05). TNF-alpha level was positively correlated with those of IL-6, sTNFR-I, and sTNFR-II. In particular, there was a highly significant positive correlation between sTNFR-I and sTNFR-II. TNF and sTNFRs in the synovial fluid of patients with TMD may be important in the pathogenesis of these disorders.
  Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontics 03/2005; 99(3):276-84. · 1.46 Impact Factor