Objective:To investigate the optimal serum antibody titer in acute stage for the diagnosis of Mycoplasma pneumoniae (MP) infection by passive agglutination, and to evaluate the clinical diagnostic value of different antibody titers.Methods:A cross-sectional study.Eighty-eight pairs of clinical serum samples were collected from children with MP infection treated at the Department of Pediatrics in Shengjing Hospital of China Medical University from December 2016 to February 2017 and Children′s Hospital of Baotou in November 2019.The four-fold change of the double serum specific antibody titer was used as the gold standard, and the receiver operating characteristic (ROC) curve was plotted.When detecting the single serum in acute stage, different antibody titers were used as positive criteria to evaluate their clinical application value in the diagnosis of MP infection and find the most appropriate serum antibody titer as the diagnostic cut-off value.Results:(1)When the serum specific antibody titer ≥1∶40 was used as the positive criterion, the sensitivity was 72.9%, the area under the ROC curve was 0.817, and the specificity was 87.5%, which might cause overdiagnosis.When the serum specific antibody titer ≥1∶160 was used as the positive criterion, the specificity was 97.5%, the area under the ROC curve was 0.775, and the sensitivity was 52.1%, which might cause missed diagnosis.When the serum specific antibody titer ≥1∶80 was used as the positive criterion, the sensitivity was 60.4%, the specificity was 97.5%, and the area under the ROC curve was 0.823, overall performing better compared with the said two criteria.(2)After the disease lasted at least 5 days, blood samples were collected.About 72.5% of the children had antibodies, and 60.0% of the children had antibody titers ≥1∶80.Conclusions:(1)When the passive agglutination method is used to detect MP infection, antibody titer ≥1∶80 is recommended as the diagnostic standard.However, in clinical practice, the diagnosis of MP infection depends on clinical and other laboratory test results.(2) It is appropriate to collect blood samples on 5-7 days of illness.If MP infection is clinically suspected, and an antibody titer of 1∶40 is also suggestive, it can perform cooperative diagnosis based on molecular biology lab results or retest at a shorter interval.

Objective To investigate the serum levels of microRNA-892b(miR-892b)and growth-associat-ed oncogene product β(GROβ)in patients with gastric cancer and their clinical significance.Methods A total of 124 patients with gastric cancer admitted to the hospital from February 2019 to February 2022 were select-ed as the gastric cancer group,and 100 volunteers with normal gastroscopy were selected as the control group during the same period.Serum levels of miR-892b and GROβ were detected in the two groups,and the rela-tionship between serum levels of miR-892b and GROβ and clinicopathological characteristics of patients with gastric cancer was analyzed.Multivariate Cox regression analysis was used to explore the influencing factors of prognosis of patients with gastric cancer.Results The serum level of miR-892b in gastric cancer group was lower than that in control group,and the serum level of GROβ was higher than that in control group(P＜0.05).There were statistically significant differences in serum miR-892b and GROβ levels in gastric cancer pa-tients with different degrees of differentiation,maximum tumor diameter lymph node metastasisand TNM stage(P＜0.05).A total of 124 patients with gastric cancer were followed up for one year after discharge,91 patients survived,and the overall survival rate was 73.39％.The one year overall survival rate of gastric cancer patients was related to the degree of differentiation,maximum tumor diameter,lymph node metastasis and TNM stage(P＜0.05).The overall survival rate of gastric cancer patients with high expression of serum miR-892b and low expression of GROβ was higher than that of patients with low expression of serum miR-892b and high expression of GROβ(P＜0.05).Multivariate Cox regression analysis showed poor differentia-tion(HR=1.839,95％CI 1.048-3.227),lymph node metastasis(HR=1.791,95％CI 1.076-2.982),TNM stage Ⅲ-Ⅳ(HR=1.660,95％CI 1.015-2.715),low expression of serum miR-892b(HR=3.040,95％CI 1.592-5.805),high expression of serum GROβ(HR=2.277,95％CI 1.503-3.451)were risk fac-tors for the prognosis of gastric cancer patients(P＜0.05).Conclusion The serum level of miR-892b is de-creased and the level of GROβ is increased in patients with gastric cancer,which is closely related to the occur-rence and development of gastric cancer.The expression of miR-892b and GROβ is related to the clinicopatho-logical characteristics and prognosis of patients,and can be used as a biological indicator to evaluate the prog-nosis of patients with gastric cancer.

Objective To evaluate the value of high-frequency color ultrasound for different types of thyroid nodules during healthy examinations. Methods A total of 150 subjects with ultrasound diagnosis of thyroid nodule abnormality were enrolled. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of ultrasound diagnosis for differentiating benign and malignant thyroid nodules were evaluated with histopathological examinations of surgical thyroid specimens as a gold standard. Results A single thyroid nodule was found in all patients, and histopathological examinations identified 102 benign thyroid nodules and 48 malignant nodules. Microcalcification showed the highest accuracy for prediction of benign and malignant thyroid nodules (98.1%; χ² = 45.67, P = 0.001), followed by taller than wider shape of thyroid nodule (92.1%; χ² = 34.06, P = 0.001), central vascularity (82.0%; χ² = 13.29, P = 0.001), halo (76.0%; χ² = 6.15, P = 0.008) and hypoechogenicity (70.3%; χ² = 10.63, P = 0.001). In addition, ultrasound diagnosis showed a 100.0% sensitivity, a 94.1% specificity, a 88.9% positive predictive value, a 100.0% negative predictive value and a 96.0% accuracy for differentiation between benign and malignant thyroid nodules (χ² = 41.830, P < 0.001). Conclusion High-frequency color ultrasound has a high diagnostic accuracy for differentiating benign and malignant thyroid nodules, and microcalcification and taller than wider shape of thyroid nodule exhibit high values for predicting the malignancy of thyroid nodules.

Objective:To investigate the effect of CHI3L1 on the biological function of chondrocytes and its role in lumbar facet joint degeneration.Methods:The human lumbar facet joint articular cartilage were collected, and the relative mRNA expression of CHI3L1 gene detected by quantitative fluorescence PCR. Then explored the correlation between joint degeneration and gender, age and relative mRNA expression of CHI3L1. Human chondrocytes were cultured in vitro. The effects of CHI3L1 on chondrocyte proliferation, cycling, and apoptosis, as well as expression of related inflammatory factors, were investigated. The mechanism by which CHI3L1 regulates the degeneration of articular cartilage was investigated using the signal transduction pathway protein chip.Results:There was a positive correlation between the grade of degeneration in lumbar facet joint and the relative expression of CHI3L1 gene mRNA ( r=0.76, P<0.001). There was no correlation with the patient's gender ( r=-0.12, P=0.500). A positive correlation between the age of patients and the relative expression of CHI3L1 gene mRNA was found ( r=0.47, P=0.005). Compared with the non-degenerative group, the expression of CHI3L1 gene mRNA significantly increased in the degenerative group, and the expression of CHI3L1 gradually increased with the aggravation in the grade of degeneration ( F=18.90, P<0.001). Compared with the non-degenerative group, the chondrocytes in the CHI3L1 group had significantly lower proliferation at 48 h (OD 490/fold=7.132), 72 h (OD 490/fold=4.803), 96 h (OD 490/fold=2.431) and 120 h (OD 490/fold=0.009). The ratio of chondrocytes in G1 phase, S phase and G2/M phase were 85.03%±3.05%, 12.78%±2.29% and 0.90%±0.76% in the CHI3L1 group, and 73.93%±2.73%, 22.81%±1.93% and 0.99%±0.87% in control group, respectively. There were significant differences in the percentage of chondrocytes in G1 phase ( t=4.70, P<0.001) and S phase ( t=5.80, P<0.001) between the two groups. The percentages of apoptosis in chondrocyte in CHI3L1 group and control group were 8.64%±0.76% and 5.68%±1.13%, which has a statistically difference ( t=4.47, P<0.001). The expression of IL-6 in chondrocytes of CHI3L1 group was 49.60±0.01 pg/ml, which was higher than that of 47.88±0.01 pg/ml in the control group ( t=132.70, P<0.001). The expression of TNF-α was 95.93±0.02 pg/ml, which was higher than 90.69±0.02 pg/ml in the control group ( t=376.10, P<0.001). There was significant difference in expression of IL-6 in chondrocytes between the CHI3L1 group and the control group ( t=132.72, P<0.001). The expression of TNF-α ( t=376.10, P<0.001) was statistically difference. Protein chip detected 53 proteins with significant differences in expression and 43 proteins with significant differences in protein phosphorylation levels. Bioinformatics analysis was used to identify 16 signaling pathways in which the above different proteins might be involved, including ErbB, PI3K, Akt, Ras, JAK, STAT3, MAPK pathway. In the MAPK pathway, the expression of MAPK1 and RAF1 proteins was higher in the chondrocytes of the CHI3L1 group than in the control group (1.094±0.00 vs. 0.814±0.00, 0.988±0.00 vs. 0.786±0.00; t=103.16, P<0.001; t=54.32, P<0.001). Compared with the control group, the expression of MAPK1 and RAF1 proteins was significantly increased in the chondrocytes of the CHI3L1 group. Conclusion:The expression of CHI3L1 is corrected to articular cartilage degeneration. CHI3L1 is able to inhibit the proliferation of articular chondrocytes, which regulated the cycling of chondrocytes from G1 phase to S phase, promote the apoptosis of chondrocytes, and promote the expression of IL-6 and TNF-α in chondrocytes. Regulation of chondrocytes biological function through the MAPK pathway, which is a potential biomarker for the clinical diagnosis and treatment of lumbar joint degeneration.

Objective: To analyze the correlations between intraoperative ultrasound and MRI metrics of the spinal cord in degenerative cervical myelopathy and identify novel potential predictive ultrasonic indicators of neurological recovery for degenerative cervical myelopathy. Materials and Methods: Twenty-two patients who underwent French-door laminoplasty for multilevel degenerative cervical myelopathy were followed up for 12 months. The Japanese Orthopedic Association (JOA) scores were assessed preoperatively and 12 months postoperatively. Maximum spinal cord compression and compression rates were measured and calculated using both intraoperative ultrasound imaging and preoperative T2-weight (T2W) MRI. Signal change rates of the spinal cord on preoperative T2W MRI and gray value ratios of dorsal and ventral spinal cord hyperechogenicity on intraoperative ultrasound imaging were measured and calculated. Correlations between intraoperative ultrasound metrics, MRI metrics, and the recovery rate JOA scores were analyzed using Spearman correlation analysis. Results: The postoperative JOA scores improved significantly, with a mean recovery rate of 65.0 ± 20.3% (p < 0.001). No significant correlations were found between the operative ultrasound metrics and MRI metrics. The gray value ratios of the spinal cord hyperechogenicity was negatively correlated with the recovery rate of JOA scores (ρ = -0.638, p = 0.001), while the ventral and dorsal gray value ratios of spinal cord hyperechogenicity were negatively correlated with the recovery rate of JOA-motor scores (ρ = -0.582, p = 0.004) and JOA-sensory scores (ρ = -0.452, p = 0.035), respectively. The dorsal gray value ratio was significantly higher than the ventral gray value ratio (p < 0.001), while the recovery rate of JOA-motor scores was better than that of JOA-sensory scores at 12 months post-surgery (p = 0.028). Conclusion For degenerative cervical myelopathy, the correlations between intraoperative ultrasound and preoperative T2W MRI metrics were not significant. Gray value ratios of the spinal cord hyperechogenicity and dorsal and ventral spinal cord hyperechogenicity were significantly correlated with neurological recovery at 12 months postoperatively.

Objective: To analyze the correlations between intraoperative ultrasound and MRI metrics of the spinal cord in degenerative cervical myelopathy and identify novel potential predictive ultrasonic indicators of neurological recovery for degenerative cervical myelopathy. Materials and Methods: Twenty-two patients who underwent French-door laminoplasty for multilevel degenerative cervical myelopathy were followed up for 12 months. The Japanese Orthopedic Association (JOA) scores were assessed preoperatively and 12 months postoperatively. Maximum spinal cord compression and compression rates were measured and calculated using both intraoperative ultrasound imaging and preoperative T2-weight (T2W) MRI. Signal change rates of the spinal cord on preoperative T2W MRI and gray value ratios of dorsal and ventral spinal cord hyperechogenicity on intraoperative ultrasound imaging were measured and calculated. Correlations between intraoperative ultrasound metrics, MRI metrics, and the recovery rate JOA scores were analyzed using Spearman correlation analysis. Results: The postoperative JOA scores improved significantly, with a mean recovery rate of 65.0 ± 20.3% (p < 0.001). No significant correlations were found between the operative ultrasound metrics and MRI metrics. The gray value ratios of the spinal cord hyperechogenicity was negatively correlated with the recovery rate of JOA scores (ρ = -0.638, p = 0.001), while the ventral and dorsal gray value ratios of spinal cord hyperechogenicity were negatively correlated with the recovery rate of JOA-motor scores (ρ = -0.582, p = 0.004) and JOA-sensory scores (ρ = -0.452, p = 0.035), respectively. The dorsal gray value ratio was significantly higher than the ventral gray value ratio (p < 0.001), while the recovery rate of JOA-motor scores was better than that of JOA-sensory scores at 12 months post-surgery (p = 0.028). Conclusion For degenerative cervical myelopathy, the correlations between intraoperative ultrasound and preoperative T2W MRI metrics were not significant. Gray value ratios of the spinal cord hyperechogenicity and dorsal and ventral spinal cord hyperechogenicity were significantly correlated with neurological recovery at 12 months postoperatively.

Objective To investigate the antibacterial effect of Fusidic acid on Mycoplasma pneumoniae and antibiotic resistant Mycoplasma pneumoniae in vitro.Methods Twenty-eight clinical strains of Mycoplasma pneumoniae isolated from patients with respiratory tract infection at Beijing Friendship Hospital Affiliated to the Capital University of Medical Sciences from January to December 2016 and 2 Mycoplasma pneumoniae reference strains were enrolled.The minimum inhibitory concentration (MIC) of Fusidic acid and Azithromycin were determined by using micro-dilution ration method.The chessboard method was used to check the antibacterial effect of combination between Fusidic acid and Azithromycin.The antibacterial activity of the Fusidic acid was evaluated by measuring the antibacterial rate of different concentrations.Results One isolate showed no mutation in 23SrRNA,26 isolates had one point mutation in loci 2063 and 1 isolate had one point mutation in loci 2064 among the 28 clinical isolates.The findings by micro-dilution method results showed that the MIC values of all the clinical isolates with mutations associated with macrolide resistance to Azithromycin were ＞ 1.000 0 mg/L,and the MIC values of all the clinical isolates with no mutations to azithromycin were ＜ 0.500 0 mg/L.The findings by micro-dilution method results showed that the MIC value of Fusidic acid for Mycoplasma pneumonia and drug resistance Mycoplasma pneumoniae was 1.000 0 mg/L.The Fractional Inhibitory Concentration index of Fusidic acid and Azithromycin combination was ≤0.500 0 mg/L.When the concentration of the Fusidic acid was lower than or equal to 32 MIC,the antibacterial effect of Fusidic acid against Mycoplasma pneumoniae increased with its higher concentration.When the concentration of the Fusidic acid was lower than or equal to 8 MIC,the longer the strain was exposed to the drug,the stronger antibacterial effect was against Mycoplasma pneumoniae.Conclusion If the treatment of Mycoplasma pneumoniae infection is not effective or the infection of patient is combined with bacteria,the application or combination of Fusidic acid may inhibit pathogenic bacteria effectively.Of course,how to use Fusidic acid in clinical treatment needs further study and discussion.

Objective To developed A laboratory diagnosis of Moraxella catarrhalis by an laboratories diagnostic method real-time fluorescence quantitative PCR assay. Methods The specific primers and probes were designed based on the sequence of outer membrane protein CopB(copB)gene in Moraxella catarrhalis,and the Taqman probe RT-PCR method was developed to detect the Moraxella catarrhalis.The standard plasmids ex-tracted from the Moraxella catarrhalis standard strains were used to constitute the standard samples,and compared with these standard samples,the sensitivity of the fluorescence quantitative PCR assay was tested by the estab-lished standard curves.The specificity of the fluorescence quantitative PCR assay was tested by the DNA samples of other bacterias in the laboratory.Meanwhile,321 throat swab samples from inpatient and outpatient child pa-tients,with asthma infection were collected as clinical samples to validate the fluorescence quantitative PCR as-say.Results The standard curve was drawn in the real-time PCR by the Taqman fluorescence reporter.During the sensitivity tests,the newly-developed real-time fluorescence PCR could detect at least 10 copies of Moraxella catarrhalis,and could successfully distinguish several DNAs of the pathogens.On the basis of the validation result of the 321 throat swab samples,there are 25 Moraxella catarrhalis with 7.79 % positive rate.Conclusion The fluorescence quantitative PCR assay is of great sensitivity and specificity,and it can be widely used for the detec-tion of Moraxella catarrhalis.

As the nerve regeneration has been researched more and more, nerve regeneration related signaling pathways after spinal cord injury (SCI) comes into the view. Inhibiting apoptosis signaling pathways may reduce the apoptosis, inflammation and nerve degenera-tion after SCI. Mitogen activated protein kinase (MAPK) signaling pathway plays an important role in regulation of gene expression, cell proliferation and apoptosis, and there was interaction among the four subordinate pathways. Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway does not only participate in the body cell survival, proliferation, differentiation and apoptosis, but also in the process of inflammatory and oxidative stress in the body. It has been found that blocking the Wnt signaling pathway after inju-ry in the central nervous system would inhibit neural axon regeneration. Exogenous Wnt3a can increase the number of neurons after SCI and promote the axon conduction and nerve function. Inhibiting mammalian target of rapamycin (mTOR) signaling pathway after SCI can signif-icantly reduce neuronal loss, cell death and well promote the functional recovery. When Notch signaling pathways are activated, neural stem cells proliferate actively and differentiation are inhibited, and stem cells enter the stage of differentiation as the pathway inhibited. Activa-tion of Ras homolog gene/Rho associated coiled coil forming protein kinase (Rho/ROCK) signaling pathways leads to the collapse of the growth cone, inhibition of axon regeneration, whereas the selective inhibition of Rho can promote axon regeneration and recovery of motor function after SCI.

Objective To explore the effect of Governor Vessel electroacupuncture in different time points on motor function and p75 neurotrophin receptor (p75NTR) after spinal cord injury. Methods A total of 180 adult male Sprague-Dawley rats were randomly divided into three groups (one day, three days and seven days after modeling), and each group was divided into normal control group, normal electroacupuncture group, sham operation group, model group and Governor Vessel electroacupuncture group with 12 cases in each group. The spinal cord injury model was established with the modified Allen's method. The normal electroacupuncture group and the Governor Vessel electroacupuncture group received electroacupuncture on Dazhui (DU14) and Mingmeng (DU04) acupoints. Basso-Beattic-Bresnahan (BBB) Scale was performed to assess the motor function of rats. The expression of p75NTR was detected with Western blotting. Results The BBB score of the model group and the Governor Vessel electroacupuncture group were significantly lower than that of the other three groups. The BBB score was significantly higher in the Governor Vessel electroacupuncture group than in the model group seven days after intervention (t=-4.510, P<0.001). The expression of p75NTR was siginificantly lower in the Governor Vessel electroacupuncture group than in the model group (P<0.01). Conclusion The expression of p75NTR increased after spinal cord injury. Governor Vessel electroacupuncture could improve the motor function, and inhibit the p75NTR expression of damaged spinal cord tissues.