Objective To carry out rigid-body inverse dynamics modelling and analysis of a self-designed 6RSS parallel bio-inspired masticatory robot.Methods Firstly,the functions of kinematic variables including translational/rotational velocities and accelerations were derived for rigid-body inverse dynamics modelling.Secondly,the rigid-body inverse dynamics model was established with the Newton-Euler's law.Finally,the chewing motion trajectories of the oral health volunteers were tracked and numerical calculations were carried out in the case where the robot was subjected to a chewing reaction force.Results Numerical calculations showed that the driving torque and the constraint force of the robot peaked when the chewing reaction force was at its maximum.Conclusion The external force has a large impact on the inverse dynamics of the robot,and theoretical references are provided for the motion control and optimal design of the robot.[Chinese Medical Equipment Journal,2024,45(3):16-22]

Objective To campare biomechanical effects of different postural compression techniques on three-dimensional model of lumbar disc herniation(LDH)by finite element analysis.Methods Lumbar CT image of a 48-year-old female patient with LDH(heighted 163 cm,weighted 53 kg)was collected.Mimics 20.0,Geomagic Studio,Solidwords and other software were used to establish three-dimensional finite element model of LDH on L4,5 segments.Compression techniques under horizon-tal position,30° forward bending and 10° backward extension were simulated respectively.After applying the pressure,the ef-fects of compression techniques under different positions on stress,strain and displacement of various tissues of intervertebral disc and nerve root were observed.Results L4,5 segment finite element model was successfully established,and the model was validated.When compression manipulation was performed on the horizontal position,30° flexion and 10° extension,the annular stress were 0.732,5.929,1.286 MPa,the nucleus pulposus stress were 0.190,1.527,0.295 MPa,and the annular strain were 0.097,0.922 and 0.424,the strain sizes of nucleus pulposus were 0.153,1.222 and 0.282,respectively.The overall displace-ment distance of intervertebral disc on Y direction were-3.707,-18.990,-4.171 mm,and displacement distance of nerve root on Y direction were+7.836,+5.341,+3.859 mm,respectively.The relative displacement distances of nerve root and interverte-bral disc on Y direction were 11.543,24.331 and 8.030 mm,respectively.Conclusion Compression manipulation could make herniated intervertebral disc produce contraction and retraction trend,by increasing the distance between herniated interverte-bral disc and nerve root,to reduce symptoms of nerve compression,to achieve purpose of treatment for patients with LDH,in which the compression manipulation is more effective when the forward flexion is 30°.

This study was aimed at creating an engineered strain of Bacillus subtilis for efficient expression of biologically active type 2 toxin B(TcdB2)derived from a highly virulent strain of Clostridium difficile.The TcdB2 gene was cloned from ST1/RT027 strain genome DNA,incorporated into the PHT01 vector,and then transformed into B.subtilis strain WB800N for prokaryotic expression.Cell toxicity assays revealed that the recombinant TcdB2 exhibited cytotoxic effects in various cells.The engineered B.subtilis strain effectively expressed biologically active TcdB2,thus providing a basis for further exploration of the pathogenic mechanisms of highly virulent strains of C.difficile and establishing a foundation for potential vaccine can-didate targets.

Background/Aims: Despite the high efficacy of direct-acting antivirals (DAAs), approximately 1–3% of hepatitis C virus (HCV) patients fail to achieve a sustained virological response. We conducted a nationwide study to investigate risk factors associated with DAA treatment failure. Machine-learning algorithms have been applied to discriminate subjects who may fail to respond to DAA therapy. Methods: We analyzed the Taiwan HCV Registry Program database to explore predictors of DAA failure in HCV patients. Fifty-five host and virological features were assessed using multivariate logistic regression, decision tree, random forest, eXtreme Gradient Boosting (XGBoost), and artificial neural network. The primary outcome was undetectable HCV RNA at 12 weeks after the end of treatment. Results: The training (n=23,955) and validation (n=10,346) datasets had similar baseline demographics, with an overall DAA failure rate of 1.6% (n=538). Multivariate logistic regression analysis revealed that liver cirrhosis, hepatocellular carcinoma, poor DAA adherence, and higher hemoglobin A1c were significantly associated with virological failure. XGBoost outperformed the other algorithms and logistic regression models, with an area under the receiver operating characteristic curve of 1.000 in the training dataset and 0.803 in the validation dataset. The top five predictors of treatment failure were HCV RNA, body mass index, α-fetoprotein, platelets, and FIB-4 index. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the XGBoost model (cutoff value=0.5) were 99.5%, 69.7%, 99.9%, 97.4%, and 99.5%, respectively, for the entire dataset. Conclusions Machine learning algorithms effectively provide risk stratification for DAA failure and additional information on the factors associated with DAA failure.

In this study, the crude polysaccharides was extracted from Shengfupian and purified by Sevag deproteinization. Then, the purified neutral polysaccharide fragment was obtained by the DEAE-52 cellulose chromatography column and Sephadex G-100 co-lumn. The structure of polysaccharides was characterized by ultraviolet spectroscopy, infrared spectroscopy, ion chromatography, and gel permeation chromatography. To investigate the anti-inflammatory activity of Shengfupian polysaccharides, LPS was used to induce inflammation in RAW264.7 cells. The expression of the CD86 antibody on surface of M1 cells, the function of macrophages, and the content of NO and IL-6 in the supernatant were examined. An immunodepression model of H22 tumor-bearing mice was established, and the immunomodulatory activity of Shengfupian polysaccharides was evaluated based on the tumor inhibition rate, immune organ index and function, and serum cytokine levels. Research indicated that Shengfupian polysaccharides(80 251 Da) was composed of arabinose, galactose, glucose, and fructose with molar ratio of 0.004∶0.018∶0.913∶0.065. It was smooth and lumpy under the scanning electron microscope. In the concentration range of 25-200 μg·mL~(-1), Shengfupian polysaccharides exhibited little or no toxicity to RAW264.7 cells and could inhibit the polarization of cells to the M1 type and reduce the content of NO and IL-6 in the cell supernatant. It could suppress the phagocytosis of cells at the concentration of 25 μg·mL~(-1), while enhancing the phagocytosis of RAW264.7 cells within the concentration range of 100-200 μg·mL~(-1). The 200 mg·kg~(-1) Shengfupian polysaccharides could alleviate the spleen injury caused by cyclophosphamide, increase the levels of IL-1β and IL-6, and decrease the level of TNF-α in the serum of mice. In conclusion, Shengfupian polysaccharides has anti-inflammatory effect and weak immunomodulatory effect, which may the material basis of Aconm Lateralis Radix Praeparaia for dispelling cold and relieving pain.
Animals ; Mice ; Interleukin-6/genetics* ; Cytokines/metabolism* ; Polysaccharides/chemistry* ; RAW 264.7 Cells ; Anti-Inflammatory Agents/chemistry* ; Spectrophotometry, Infrared

The cases of feeling comfort during acupuncture and moxibustion treatment in literature were summarized and its biological basis was explored. A simple classification of comfort was made, and the importance of obtaining comfort in acupuncture treatment was pointed out. Considering the pursuit of less pain and harmlessness in modern clinical treatment, sugar needle should be advocated and popularized in current clinical practice of acupuncture and moxibustion.
Sugars ; Moxibustion ; Acupuncture Therapy ; Emotions ; Needles

OBJECTIVE: To investigate the relationship between the shape of the lateral wall and the early failure of internal fixation in the fracture of the femoral trochanteric region(FFT). METHODS: Total 295 patients with femoral trochanteric fracture underwent internal fixation from January 2015 to January 2020 were selected. The patients were divided into two groups according to whether there was early internal fixation failure after surgery, 19 patients in the failure group and 276 patients in the normal group. Gender, affected side, age, AO classification, body mass index(BMI), preoperative hemoglobin, X-ray measurement of lower lateral wall thickness, preoperative internal diseases, intraoperative blood loss, postoperative tip apex distance(TAD), postoperative neck shaft angle, operation time and other data were compared between two groups. The shape of the lateral wall was compared between two groups, and the correlation between the shape of the lateral wall and the early internal fixation failure of femoral trochanteric fracture was analyzed. RESULTS: All patients were followed up for more than 1 year. There was no significant difference between two groups in terms of intraoperative blood loss, operation time, postoperative TAD, and postoperative neck shaft angle(P>0.05). At the latest follow-up, the visual anaglue scale (VAS) of the failure group was higher than that of the normal group(P<0.01), and the Harris score of the failure group was lower than that of normal group(P<0.05). The receiver operator characteristic (ROC) curve between shape of lateral wall and failure of early internal fixation of femoral trochanteric fracture was drawn. The critical value of the midpoint lateral wall thickness was 16.5 mm, and the area under the ROC curve was 0.845;The critical value of average sidewall thickness was 16.5 mm, and the area under ROC curve was 0.838;The critical value of the axial area of the sidewall was 7.5 mm, and the area under the ROC curve was 0.826. CONCLUSION The shape of the lateral femoral wall measured by CT could be used as a predictive factor for the early failure of internal fixation of femoral trochanteric fractures. For patients at risk, more reasonable surgical plans and postoperative preventive measures should be developed.
Humans ; Treatment Outcome ; Fracture Fixation, Intramedullary ; Bone Nails ; Retrospective Studies ; Hip Fractures/surgery* ; Fracture Fixation, Internal

AIM: To evaluate the efficacy and safety of different Conbercept treatment on diabetic macular edema(DME)with 3+PRN and 5+PRN.METHODS: Retrospective case-control study. A total of 51 patients(92 eyes)with DME who were treated in our hospital during December 2019 and June 2020 were included, and they were divided into 3+PRN group with 26 cases(48 eyes)and 5+PRN group with 25 cases(44 eyes). All patients received monthly follow-up for 12mo and the changes of best-corrected visual acuity(BCVA)and central macular thickness(CMT), the number of intravitreal injections and the occurrence of complications were compared and observed in the two groups.RESULTS:After follow-up for 12mo, there was no difference in the average injection times between the 3+PRN group and the 5+PRN group(7.24±0.91 times vs. 7.56±1.04 times, P=0.117). The BCVA and CMT of the two groups improved at 3, 6, 9, and 12mo after treatment compared with those before treatment(all P<0.05), and the BCVA and CMT of the 5+PRN group were better than those of the 3+PRN group at 6, 9, and 12mo after treatment(all P<0.05). During the follow-up period, no serious adverse events occurred in the two groups of patients, and the total incidence of ocular adverse events in the two groups was 27%. All adverse events were improved after symptomatic treatment.CONCLUSION: Both the 3+PRN and 5+PRN treatment strategy of Conbercept can treat DME safely and effectively, the total times of injection were comparable. However, the BCVA and CMT improved more in the 5+PRN group than that in 3+PRN group.

Objective: To investigate the effect of 1-acyl-sn-glycerol-3-phosphate acyltransferaseδ (APGAT4) on the growth and lenvatinib resistance of hepatocellular carcinoma (HCC), and provide novel targets for HCC treatment. Methods: Using the bioinformatics methods to screen out upregulated genes in lenvatinib resistant cell lines from GEO dataset and survival related genes from TCGA dataset. Immumohistochemical staining was used to detect the expression AGPAT4 in HCC tissues, and its correlation with patients' survival. CCK8, EdU, cell cycle, and cell apoptosis assays were used to investigate the impact of role AGPAT4 on the proliferation and lenvatinib reistance of HCC cells. AGPAT4 stable knockdown cell line and subcutaneous nude mouse model were established to test the therapeutic effects of Lenvatinib. Analysis of variance was used to compare the differences between data sets. Results: APGAT4 was the common factor that predicted poor survival and Lenvatinib resistance. The mRNA and protein levels of APGAT4 were significantly upregulated in HCC tissues compared to the para-tumor tissues (P < 0.05). Using siRNA could significantly knocked down the mRNA and protein expression of APGAT4 in HCC cell lines Hep3B and HCCLM3. Compared with the control group, the proliferation ability of HCC cell lines (Hep3B and HCCLM3) in APGAT4 knockdown group was significantly inhibited, and the cell cycle was arrested in G2/M phase (P < 0.05). In addition, compared to the control group, HCC cell lines (Hep3B and HCCLM3) in APGAT4 knockdown group showed significant decrease in the Lenvatinib half maximal inhibitory concentration, and were more sensitive to lenvatinib-induced apoptosis (P < 0.05). In HCC subcutaneous nude mouse model, compared to the control group, the growth of tumor in APGAT4 knockdown group was significantly suppressed, and more apoptosis cells were induced (P < 0.05). Conclusion: APGAT4 promotes the growth and Lenvatinib resistance of HCC, which is a potential target for HCC treatment. Targeting APGAT4 treatment is conducive to inhibit the growth and Lenvatinib resistance of HCC.
Animals ; Mice ; Carcinoma, Hepatocellular/pathology* ; Liver Neoplasms/pathology* ; Mice, Nude ; Cell Line, Tumor ; Cell Proliferation ; RNA, Messenger ; Gene Expression Regulation, Neoplastic

Objective:To study the long-term clinical effect of transvaginal mesh (TVM) and pelvic floor reconstruction with native tissue repair (NTR) in the treatment of advanced pelvic organ prolapse (POP).Methods:Totally 207 patients with advanced POP who were treated in Hunan Provincial Maternal and Child Health Care Hospital from Jan. 2016 to Sep. 2019 were enrolled. The patient′s pelvic organ prolapse quantification were all at degree Ⅲ or above, and they all complained for different degree of symptoms. They were divided into two groups according to the different surgical methods, TVM group and NTR group. In TVM group, the mesh was implanted through the vagina for pelvic floor reconstruction, while in NTR group, the traditional transvaginal hysterectomy combined with uterosacral ligament suspension and anterior and posterior wall repair, as well as perineal body repair were performed. The median follow-up time was 60 months, during the follow up time, 164 cases (79.2%, 164/207) had completed follow-up, including 76 cases in TVM group and 88 cases in NTR group. The perioperative data and complication rates of the two groups were compared, and the subjective and objective outcomes of the two groups at 1, 3 and 5 years were observed, respectively. The objective efficacy was evaluated by three composite criteria, namely: (1) the distance from the farthest end of the prolapse of the anterior and posterior wall of the vagina to the hymen is ≤0 cm, and the descending distance of the top is ≤1/2 of the total length of the vagina; (2) determine the disappearance of relevant POP symptoms according to “Do you often see or feel vaginal mass prolapse？”; (3) no further operation or pessary treatment was performed due to prolapse. If the above three criteria were met at the same time, the operation is successful; otherwise, it was recurrence. The subjective efficacy was evaluated by the pelvic floor distress inventory-short form 20 (PFDI-20) and pelvic floor impact questionnaire-short form 7 (PFIQ-7).Results:The median follow-up time of the two groups was 60 months (range: 41-82 months). Five years after the operation, the subjective and objective cure rates of TVM group were 89.5% (68/76) and 94.7% (72/76), respectively. The subjective and objective cure rates in NTR group were 80.7% (71/88) and 85.2% (75/88), respectively. There were significant differences in the subjective and objective cure rates between the two groups ( χ2=9.869, P=0.002; χ2=3.969, P=0.046). The recurrence rate of TVM group was 5.3% (4/76), and that of NTR group was 14.8% (13/88). There was a significant difference between the two groups ( P=0.046). The postoperative PFDI-20 and PFIQ-7 scores of the two groups were significantly lower than those before surgery, and there were significant differences of the two groups before and after surgery (all P<0.05). Postoperative mesh exposure in TVM group was 1.3% (1/76). Conclusions:The long-term outcomes between the two groups show that the subjective and objective outcomes of pelvic floor reconstruction in TVM group are significantly higher than those in NTR group, and the recurrence rate is significantly lower than that in NTR group. TVM has certain advantages in the treatment of advanced POP.