DNA methylation of DKK-1 may correlate with pathological bone formation in ankylosing spondylitis.

OBJECTIVE: To investigate DNA methylation (DNAm) status of dickkopf-associated protein 1 (DKK-1) in ossified hip capsule synovium and serum among patients with ankylosing spondylitis (AS). METHODS: Western blot was applied to detect the level of DKK-1 protein expression in hip joint capsule tissues from four patients with AS as well as four patients with femoral neck fracture (FNF) caused by trauma as control. DKK-1 gene promoter methylation (GPM) was examined by methylation-specific polymerase chain reaction. Reverse transcription-polymerase chain reaction was performed to examine the messenger RNA (mRNA) levels of DKK-1, ß-catenin, and Wnt3a in both tissue and serum. The DNAm status of serum DKK-1 was measured among 36 patients with AS and syndesmophytes (AS + syndesmophytes group), 40 patients with AS but no syndesmophyte (AS group), and 42 healthy individuals (control group). Also, the serum levels of DKK-1 were measured by enzyme-linked immunosorbent assay. The modified New York criteria (mNYC) together with the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) were adopted to examine the radiographic progression of AS. The receiver operating characteristic (ROC) curve was applied to investigate the diagnostic value of the methylation rate of DKK-1 with regard to radiographic progression. RESULTS: The expressions of DKK-1 protein and mRNA in hip joint capsule tissues of AS patients were significantly lower, while DKK-1 GPM rate, ß-catenin mRNA, and Wnt3a mRNA were markedly higher when compared with FNF group. For serum samples, the DKK-1 methylation rate was significantly higher in AS+ syndesmophytes group in contrast to AS group and healthy controls. Serum levels of DKK-1 protein and mRNA in AS with syndesmophytes group were markedly decreased, while ß-catenin mRNA and Wnt3a mRNA expressions were significantly increased than AS with no syndesmophyte group and the healthy control group. AS patients in Grade 4 showed a significantly higher serum DKK-1 GPM rate than those in Grade 3 based on mNYC. Serum DKK-1 GPM level was markedly and positively correlated with mSASSS. Serum levels of DKK-1 in AS+ syndesmophytes group were markedly lower compared with AS but no syndesmophyte group and healthy controls. ROC curve analysis indicated that serum DKK-1 methylation rate serves as a decent indicator for AS radiographic progression. CONCLUSION: DNAm of DKK-1 may correlate with pathological bone formation in AS, which may provide new strategies for the treatment of AS abnormal bone formation.

Study subnetwork developing pattern of autism children by non-negative matrix factorization.

BACKGROUND: As a developmental disorder, the brain networks of autism children show abnormal patterns compared with that of typically developing. The differences between them are not stable due to the developing progress of children. It has become a choice to study the differences of developing trajectories between autistic and typically developing children by investigating the change of each group respectively. Related researches studied the developing of brain network by analyzing the relationship between network indices of the entire or sub brain networks and the cognitive developing scores. METHODS: As a matrix decomposition algorithm, non-negative matrix factorization (NMF) was applied to decompose the association matrices of brain networks. By NMF, we can obtain subnetworks in an unsupervised way. The association matrices of autism and control children were estimated by their magnetoencephalography data. NMF was applied to decompose the matrices to obtain common subnetworks of both groups. Then we calculated the expression of each subnetwork in each child's brain network by two indices, energy and entropy. The relationship between the expression and the cognitive and development indices were investigated. RESULTS: We found a subnetwork with left lateralization pattern in α band showed different expression tendency in two groups. The expression indices of two groups were correlated with cognitive indices in autism and control group in an opposite way. In γ band, a subnetwork with strong connections on right hemisphere of brain showed a negative correlation between the expression indices and development indices in autism group. CONCLUSION: NMF algorithm can effectively decompose brain network to meaningful subnetworks. The finding of α band subnetworks confirms the results of abnormal lateralization of autistic children mentioned in relevant studies. We assume the results of decrease of expression of the subnetwork may relate to the dysfunction of mirror neuron. The decrease expression of γ subnetwork of autism may be related to the weaken process of high-frequency neurons in the neurotrophic competition.

[Asymmetric response mechanism of auditory event related potentials].

The classical auditory oddball paradigm is a commonly used experimental paradigm for evoking event related potentials (ERPs). The present study was aimed to explore the auditory cognitive processing mechanism of space perception of human brain. We employed an auditory oddball paradigm of binaural unbiased and biased sound intensity to compare and analyze the response characteristics of ERP. By focusing on the spatial lateralization characteristics of P300 and mismatch negativity (MMN) components, we analyzed their lateralization trends according to the laterality index. We found that both P300 and MMN components showed right-hemisphere lateralization phenomenon under the stimulation of asymmetric intensity of auditory acoustic. The results suggested that the right hemisphere of human brain played a key role in spatial information processing. The results also indicated that the hemispherical characteristics of the brain were not related to the actual spatial direction of the auditory stimulus, but were determined by the hemispherical functions of the brain. Furthermore, the results suggested that the MMN components induced by spatial differences were stronger in females than those in males.

[Recurrence and survival analysis of postoperative patients aged 25 to 59 years with differentiated thyroid carcinoma].

OBJECTIVE: To investigate the recurrence and survival of postoperative patients with differentiated thyroid carcinoma (DTC) aged from 25 to 59 years. METHODS: We retrospectively analyzed the clinical data of 36 patients with DTC treated in our hospital from 1996 to 2011, and the recurrence and survival status of the patients were recorded. Kaplan-Meier analysis was carried out to analyze factors that affect the patient's survival. RESULTS: Nine patients died of recurrence or metastasis, and the interval between the initial surgery and recurrence ranged from 22 to 46 months. The survival time of the 36 patients ranged from 34 to 135 months with a 10-year survival rate of 75.0%. Kaplan-Meier analysis showed that male patients had a significantly shorter mean survival time than female patients (Χ2=3.164, P=0.041); the median survival time of patients aged 45-59 years was obviously shorter than that of patients aged 25-44 years (Χ2=4.622, P=0.032); the postoperative survival in patients with 131I therapy was significantly longer than those who did not receive the therapy (Χ2=4.527, P=0.033), and was not affected by total excision of the thyroid gland (Χ2=0.988, P=0.320). No significant difference was found in the median survival of patients in different clinical stages (Χ2=2.2132, P=0.167). CONCLUSION: In young and middle-aged patients with DTC, postoperative recurrence is the most likely in 2 to 4 years after the surgery. Male patients at 45-59 years of age who do not receive 131I treatment are at high risks of tumor recurrence.