Objective To construct the recombinant streptolysin O antigen(SLO) prokaryotic expression plasmid and establish its best expression condition in Escherichia coli .Methods The DNA fragment encoding SLO was amplified from streptococcal ge-nomic DNA template by PCR ,and then incorporated into pET-32a(+ ) vector to construct pET-32a(+ )-SLO recombinant plas-mid .pET-32a(+ )-SLO was transformed into Escherichia coli BL21(DE3) and SLO protein was expressed and purified by isopro-pyl-β-D-thiogalactoside(IPTG)-induction and auto-induction ,respectively .Results The results of DNA electrophoresis and DNA sequencing showed that pET-32a(+ )-SLO recombinant plasmid was constructed successfully .When IPTG at different concentra-tion was used ,SLO expressed as inclusion body and its expression efficiency was low .Under auto-induction condition ,SLO ex-pressed as partly soluble manner ,and its expression efficiency increased .Conclusion The prokaryotic expression plasmid pET-32a (+ )-SLO is constructed successfully and the best condition for SLO expression and purification from Escherichia coli culture is es-tablished ,which lay the foundation for further basic and clinical application research with SLO .

Objective:To evaluate the clinical performance of low-count platelet(PLT) samples for Mindray BC-6800 automatic hematology analyzer and compare the detection results between two sampling mode(automatic injection, manual injection).Methods: To evaluate the repeatability and contamination rate of low-count platelet samples depend on ICHC, CLSI and other standards; to choose 108 blood samples with thrombocytopenia and detect them in two kinds of detection mode (automatic and manual operation), and then evaluate the consistency of low-count PLT samples between the two modes.Results: The results of two detection modes for low-count platelet samples showed there were well repeatability between them. The CV% of those samples which PLT were upon 20×109/L can be assurance within 5% in two modes. The value and fluctuation of SD and range of those samples which PLT were under 20×109/L were smaller; the SD of two modes were 0.5 and 0.8, respectively; and the Range were 1 and 2, respectively. Both of the two modes were less than 1% in carryover rates, high PLT accounts has no influence on low accounts. The correlation coefficient was up to 0.9910 between the two modes by analyzing the 108 blood samples. The results demonstrate there were low deviation and well consistency between the two modes by analyzing medical decision level concentration point for them.Conclusion: Mindray BC-6800 has good clinical performance to detect low-count PLT samples and there are well consistency between automatic and manual operation. Clinical Laboratory chooses which suitable mode to detect samples may depend on self-situation.

Objective: To study the mechanism of Tuina in the treatment of skeletal muscle injury. Methods: Rabbits were heavily beaten at gastrocnemius muscle to make acute contusion model and then treated respectively by early Tuina and routine Tuina. The number of satellite cells of skeletal muscles was observed. Results: The number of the satellite cells continued to grow in both groups, and it began to increase significantly 3-5 days after Tuina treatment. Early Tuina treatment produces larger number of satellite cells than routine Tuina treatment.Conclusion: Early Tuina treatment is helpful to the marked recovery of skeletal muscles by increasing the number of satellite cell.

Objective To analyze of related factors in affecting condylar buttress plate (CBP) surgical treatment of distal femoral fractures.Methods One hundred patients with distal femoral fractures were grouped according to eight related factors (gender,age,fracture type,fracture classification,surgical time,reset quality,whether bone graft and plaster braking),respectively.Operative efficacy was scored by the Neer knee functional score table,and score ≥ 72 was excellent,while ＜ 72 was good.Eight related factors were carried out single factor analysis with x2 test to compare the operative efficacy of each group,then the related factors with single factor analysis result of P＜0.05 were put in Logistic multifactor regression analysis,in order to clarify the independent risk factors for CBP treatment of distal femoral fractures.Results There was no significant difference (P＞0.05) in the operative efficacy between male and female group,open fracture and closed fracture group.The difference between youth,middle-aged and elderly group,type A and type C fracture group was statistically significant (P＜0.05).The operative efficacy of patients got surgery within 7 d was obviously better than those who got surgery 7 d later (P＜0.05).The operative efficacy of patients who had no intraoperative bone graft was better than those who had bone graft (P＜0.05).The operative efficacy of satisfactory reset group and none plaster braking group was better than that of unsatisfied reset group and plaster braking group (P＜0.05),respectively.Conclusions Age,fracture type and reset quality are CBP therapy independent risk factors for the efficacy of operation for patients with distal femoral fractures,which will provide some reference for improving the operative efficacy of CBP operation in treatment of distal femoral fractures.

Objective To investigate the role of dual-source parallel radio frequence (RF) and single-source excitation in liver imaging at 3.0 T MR.Methods This study was a retrospective analysis.One hundred and seven subjects underwent a 3.0 T TX MR scanning including axial spectrally selective attenuated inversion recovery (SPAIR) T2WI,axial DWI and coronal balanced-fast field echo( Balanced FFE).Each sequence was carried out with both single-source and dual-source RF excitation.Student＇s t test was used to compare the differences between single-source and dual-source RF excitation in the image uniformity,signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR).Wilcoxon signed rank test was used to determine whether there was difference between conventional and parallel transmission in the score of image quality.Reader agreement was assessed using the Cohen＇s Kappa test.Results For the image uniformity,there was significant difference between single-source and dual-source excitation (418.40 ± 66.75 for single-source vs.416.26 ± 50.61 for dual-source,t =2.524,P ＜ 0.05 ).There also existed significant difference between single-source and dual-source excitation in SNR and CNR,respectively.The SNR and CNR of parallel transmission (22.03 + 12.16 and 18.33 ± 10.01,respectively) were both higher than those of single transmission (20.36 ± 11.21 and 15.22 ± 8.95,respectively) ( t =- 2.630,P ＜ 0.05 for SNR and t =- 4.238,P ＜ 0.05 for CNR).Image quality comparisons revealed significantly better results with dual-source than single-source RF excitation at SPAIR T2 WI ( 1.40 + 0.42 vs.1.81 ± 0.27 ),DWI ( 1.08 ± 0.40 vs.1.63 ± 0.36 ) and Balanced FFE sequence ( 0.95 ± 0.45 vs.1.65 ± 0.37,Z =- 5.894,- 5.801 and - 6.985,respectively,P ＜ 0.01 ).In the comparison of image quality,the agreement between the two readers was very good ( Kappa ＞ 0.8,P ＜ 0.05 ).Conclusion Dual-source parallel RF excitation MR imaging in liver enables reducing dielectric shading,improving homogeneity of the RF magnetic induction field,and increasing SNR and CNR at 3.0 T.

Objective To investigate the episodic memory monitoring in patients with white matter lesions (WML) and explore the relevance of episodic memory disorder and memory monitoring and the possible mechanism.Methods The feeling of knowing-episodic memory (FOK-EM) paradigm was adopted and subsequently administered in 30 WML patients and 30 control participants who were matched in age and educational level.Results Compared with control group (cued recall 4.37 ± 1.59;recognition 8.73 ± 1.05),the episodic memories of WML patients were significantly impaired on the cued recall performance (3.30 ± 1.51,t =2.666,P ＜ 0.05) and recognition performance (7.23 ± 0.77,t =6.306,P ＜ 0.01).Furthermore,the accuracy of FOK judgment (-0.13 ± 0.31),the correct judgment and correct recognition of FOK-EM (23.16％ ±5.96％) and the correct judgment and false recognition of FOK-EM (34.26％ ± 7.65％) in the WML patients group were significantly different compared with the control group (the accuracy of FOK judgment:0.34 ± 0.27,t =6.280,P ＜ 0.01;the correct judgment and correct recognition:35.12％ ± 6.82％,t =7.234,P ＜ 0.01;the correct judgment and false recognition:19.27％ ±6.50％,t =-8.174,P ＜ 0.01).In addition,the correct judgment and false recognition performance were positively correlated with the severity of periventricular lesions and deep white matter lesions in the WMLpatients group (r=0.716,P＜0.01;r=0.598,P＜0.01).Conclusions The WML patients demonstrated an overestimation of their recognition ability of episodic memory.Moreover,this impairment of memory monitoring was correlated with the deficit of executive function caused by the damage of the prefrontal-subcortical circuit,indicating that this mechanism could be an influential factor of episodic memory disorder in WML.

Objective To explore the clinical value of the dual-low-dose with low tube voltage for head and neck CTA. Methods One hundred and sixty patients who were clinically suspected head and neck vascular disease underwent CTA procedure were propective selected, and whose body mass index (BMI) was also lower than 25 kg/m2. Forty cases were randomly selected as conventional group(120 kV,150 mAs, iodine 320 mg/ml), the other 120 cases were as the low dose group. The low dose group divided into three subgroups according to the random number table method, which were low iodine group (37 cases;120 kV,150 mAs, iodine 270 mg/ml), low tube voltage group (42 cases;100 kV,150 mAs, iodine 320 mg/ml) and low iodine and tube voltage group (41 cases;100 kV,150 mAs, iodine 270 mg/ml). The carotid bifurcated CT value, standard deviation (SD), signal-to-noise ratio (SNR), iodine intake and effective radiation dose (ED) of the four groups were recorded,all data undertook statistical analysis useing one-way ANOVA. Meanwhile, the subjective image quality score was applied to evaluate the image quality, and the differences among groups were compared by Wilcoxon signed ranks test. Results The image quality score were (2.85±0.19),(2.33 ± 0.34),(2.26 ± 0.32),(2.87 ± 0.22) in the four groups, and there was no statistical difference between groups(P>0.05).The carotid bifurcated CT value were respectively (380±30),(314±27),(514±52) and (425±28) HU in conventional, low iodine, low tube voltage and dual-low-dose groups, and the iodine intake were (18.85±2.10), (15.75±1.78), (18.53±1.98), (15.62±1.92) g, the ED of the four groups were (1.74±0.14), (1.73± 0.11), (1.32 ± 0.08) and (1.35 ± 0.09) mSv, the difference were all statistically significant (P<0.01). Furthermore, the iodine intake and the effective radiation dose in dual-low-dose group were significantly lower than the conventational group. Conclusions Head-and-neck CTA with dual-low-dose scan can provide same quality images as using 100 kV and high dose iodine contrast agent, and which also significantly reduced the ED and iodine intake greatly. Thus, this scanning program has great clinical value.

Lung cancer is one of the primary causes of cancer-induced death among the world. Although the network of molecular implicated in lung cancer is gradually revealed, the exact molecular mechanism of its occurrence and development has not been fully elucidated. As a class of small and endogenous single-stranded non-coding RNAs, microRNAs (miRNAs) are found in a wide range of organisms from plants, viruses to humans. miRNAs involve various functions in normal lung tissue development. They take part in a large amount of biological processes including cell growth, metabolism, proliferation and differentiation. However, aberrant expression of miRNAs could induce the occurrence, development, invasion and metastasis of lung tumor, so it is deemed the novel biomarkers. Similar to that of protein-coding genes, expression and function of miRNA are regulated by various factors and the epigenetic network which includes DNA methylation and histone modification. Moreover, key enzymes driving epigenetic modifications are regulated by miRNAs. Therefore, better understanding of inextricable linkage between miRNAs and epigenome will provides a basis for the feasibility of miRNA-orientated diagnostic, therapeutic and prognostic strategies related to lung cancer in future.

Objective: To investigate the effects of acupotomy on skeletal muscle fibrosis and collagen deposition in a rabbit knee osteoarthritis (KOA) model. Methods: Rabbits (n = 18) were randomly divided into control, KOA, and KOA + acupotomy (Apo) groups (n = 6). The rabbits in the KOA and Apo groups were modeled using the modified Videman's method for 6 weeks. After modeling, the Apo group was subjected to acupotomy once a week for 3 weeks on the vastus medialis, vastus lateralis, rectus femoris, biceps femoris, and anserine bursa tendons around the knee. The behavior of all animals was recorded, rectus femoris tissue was obtained, and histomorphological changes were observed using Masson staining and transmission electron microscopy. The expression of transforming growth factor-β1 (TGF-β1), Smad 3, Smad 7, fibrillar collagen types I (Col-I) and III (Col-III) was detected using Western blot and real-time polymerase chain reaction (RT-PCR). Results: Histological analysis revealed that acupotomy improved the microstructure and reduced the collagen volume fraction of rectus femoris, compared with the KOA group (P = .034). Acupotomy inhibited abnormal collagen deposition by modulating the expression of fibrosis-related proteins and mRNA, thus preventing skeletal muscle fibrosis. Western blot and RT-PCR analysis revealed that in the Apo group, Col-I, and Col-III protein levels were significantly lower than those in the KOA group (both P < .01), same as Col-I and Col-III mRNA levels (P = .0031; P = .0046). Compared with the KOA group, the protein levels of TGF-β1 and Smad 3 were significantly reduced (both P < .01), as were the mRNA levels of TGF-β1 and Smad 3 (P = .0007; P = .0011). Conversely, the levels of protein and mRNA of Smad 7 were significantly higher than that in the KOA group (P < .01; P = .0271). Conclusion Acupotomy could alleviate skeletal muscle fibrosis and delay KOA progress by inhibiting collagen deposition through the TGF-β/Smad pathway in the skeletal muscle of KOA rabbits.

Objective:To explore the effect of intermittent angle traction on the supine position combined with acupoint application on the changes of cervical radiculopathy related biological parameters.Methods:Randomized controlled trial. A total of 100 patients with radiculopathy cervical spondylosis treated in the Second Affiliated Hospital of Heilongjiang University of Traditional Chinese Medicine from February 2019 to February 2021 were selected and randomly divided into observation group ( n=50) and control group ( n=50). Patients in the control group were given conventional treatment with western medicine, and patients in the observation group were given acupoint application combined with supine intermittent angle traction combined with treatment. Both groups were treated for 3 months. The Japanese Orthopaedic Association Spinal Cord Function (JOA), Cervical Disability Index (NDI), Pain Visual Analogue Score (VAS) and the changes in intervertebral foramen volume of two groups were compared before and after treatment. The difference in clinical efficacy between the two groups after treatment was observed. We took a thin spiral CT film of the patient's cervical spine, established a three-dimensional finite element model of the cervical spine, and compared the differences in related indicators between the two groups before and after treatment. Results:The total effective rate was 94.0% (47/50) in the observation group and 70.0% (35/50) in the control group, and there was a significant difference between the two groups ( χ2=9.76, P=0.002). After treatment, the JOA score in the observation group was significantly higher than that of the control group ( t=6.23, P<0.01), the NDI score, VAS score were significantly lower than those in the control group ( t values were 5.17,9.13, P<0.01), the intervertebral foraminal volume [(8.45±1.27)mm 3vs. (7.18±1.38)mm 3, t=4.79] was significantly higher than that of the control group ( P<0.01), and C 4-7 cervical vertebra flexion [(7.15±0.87)° vs.(5.64±0.78)°, t=9.14], retroflexion [(8.53±0.73)° vs. (7.15±0.68)°, t=9.78], sidebend [(6.57±0.71)° vs. (5.28±0.67)°, t=9.34], rotated [(7.89±0.52)° vs. (6.54±0.48)°, t=13.49] were significantly higher than those in the control group ( P<0.01); C 4-7 disc flexion [(1.41±0.09) kPa vs. (2.01±0.12) kPa, t=28.28], retroflexion [(1.54±0.07) kPa vs. (2.01±0.08) kPa, t=31.26], sidebend [(1.24±0.07) kPa vs. (1.89±0.13) kPa, t=31.13], rotated [(1.23±0.06)kPa vs. (1.85±0.11)kPa, t=34.99] were significantly lower than those in the control group ( P<0.01). Conclusion:The supine intermittent Angle traction combined with acupoint application in the treatment of cervical spondylotic radiculopathy can relieve the neck pain, improve the neck function, restore the physiological curvature of the cervical spine, and promote the recovery of cervical biomechanics.