Anisotropic Hyperelastic Strain Energy Function for Carbon Fiber Woven Fabrics.

The present paper introduces an innovative strain energy function (SEF) for incompressible anisotropic fiber-reinforced materials. This SEF is specifically designed to understand the mechanical behavior of carbon fiber-woven fabric. The considered model combines polyconvex invariants forming an integrity basisin polynomial form, which is inspired by the application of Noether's theorem. A single solution can be obtained during the identification because of the relationship between the SEF we have constructed and the material parameters, which are linearly dependent. The six material parameters were precisely determined through a comparison between the closed-form solutions from our model and the corresponding tensile experimental data with different stretching ratios, with determination coefficients consistently reaching a remarkable value of 0.99. When considering only uniaxial tensile tests, our model can be simplified from a quadratic polynomial to a linear polynomial, thereby reducing the number of material parameters required from six to four, while the fidelity of the model's predictive accuracy remains unaltered. The comparison between the results of numerical calculations and experiments proves the efficiency and accuracy of the method.

Peripheral enthesitis assessed by whole-body MRI in axial spondyloarthritis: Distribution and diagnostic value.

Objective: To determine the distribution and diagnostic value of peripheral enthesitis detected by whole-body MRI (WBMRI) in axial spondyloarthritis (axSpA) diagnosis, and to determine the value of the peripheral enthesitis score in axSpA assessment. Methods: Sixty axSpA patients [mean age of 33.2 (24.8-40.6) years] and 50 controls with chronic low back pain (LBP) [mean age of 34.7 (28.3-41.1) years] were enrolled. The gold standard was physician's comprehensive diagnosis based on current classification criteria and physical examination. All subjects underwent WBMRI, and 47 peripheral entheses were assessed for each patient with scores of 0-188. Results: WBMRI identified 155 enthesitis sites in 78.3% (n = 47) patients with axSpA. Meanwhile, 23 enthesitis sites were identified in 32% (n = 16) controls. The pelvis had the maximum number of enthesitis sites (52, 33.5%) in axSpA patients. Pelvic and anterior chest wall enthesitis had the highest sensitivity (51.67%) and specificity (100%) in axSpA diagnosis, respectively. There were different manifestations of enthesitis subtypes between axSpA patients and the control group. Osteitis was more present than soft-tissue inflammation in axSpA patients. The AUC for the number of enthesitis sites was 0.819 (95% CI 0.739-0.899), and that for the enthesitis score was 0.833 (95% CI 0.755-0.910), indicating statistically significant differences (P = 0.025). Based on the Youden index and clinical need, three enthesitis sites (sensitivity of 53.33, specificity of 98, and Youden index of 0.51) and enthesitis score (sensitivity of 58.33, specificity of 98, and Youden index of 0.56) may have the greatest value for axSpA diagnosis. Conclusion: The distribution of peripheral enthesitis can be adequately assessed by whole-body MRI, which could help diagnose axial spondyloarthritis. The enthesitis score may provide a more accurate assessment and diagnostic tool in axSpA compared with enthesitis site counting.

Clinical Value of sTREM-1, PCT, and 1,3-ß-D Glucan in Diagnosis of Immune-Associated Pulmonary Interstitial Disease with Fungal Infection.

Background: Fungal infection in the lungs can cause fungal infectious diseases. This disease develops rapidly and involves a wide range. Pathogenic fungi are also more serious types of pathogenic bacteria. If it invades deep organs and tissues, it will endanger life, so it needs timely diagnosis. Aim: To investigate the diagnostic value of serum soluble myeloid cell triggering receptor-1 (sTREM-1), procalcitonin (PCT), and 1,3-ß-D glucan detection in immune related lung disease complicated with fungal infection. Methods: In this study, a case-control study was conducted. 50 patients with immune-related pulmonary disease complicated with fungal infection (infection group) diagnosed by sputum culture in our hospital from January 2017 to December 2021 were selected as the control group, and 50 patients with immune-related pulmonary disease without fungal infection were selected as the control group. The levels of sTREM-1, PCT, and 1,3-ß-D glucan were compared in the two groups. The receiver operating characteristic (ROC) was used to analyze the value of the three indicators in the diagnosis of immune-related pulmonary disease complicated with fungal infection, and the changes of the three indicators before and after treatment were compared. Results: The levels of sTREM-1, PCT, and 1,3-ß-D glucan in the infection group were higher than those in the control group (P < 0.05). The levels of sTREM-1, PCT, and 1,3-ß-D glucan in the infection group after treatment were significantly lower than those before treatment (P < 0.05). The AUC value of sTREM-1 in the diagnosis of immune-related pulmonary diseases complicated with fungal infection was 0.980, the sensitivity was 97.11%, and the specificity was 83.06%. The AUC value of PCT in the diagnosis of immune-related pulmonary diseases complicated with fungal infection was 0.860, the sensitivity was 80.00%, and the specificity was 72.41%. The AUC value of 1,3-ß-D glucan in the diagnosis of immune-related pulmonary diseases complicated with fungal infection was 0.993, the sensitivity was 98.74%, and the specificity was 99.16%. The levels of sTREM-1, PCT, and 1,3-ß-D glucan in the infection group after treatment were considerably lower than those before treatment, and the difference was statistically significant (P < 0.05). Conclusion: The detection of sTREM-1, PCT, and 1,3-ß-D glucan levels has high clinical value for the diagnosis of immune-related pulmonary diseases complicated with fungal infection.

Prevalence of metabolic syndrome in patients with rheumatoid arthritis in eastern China-A hospital based study.

OBJECTIVE: The purpose of this hospital clinic based study was to evaluate the potential risk factors associated with the prevalence of MetS in RA population. METHODS: From January 2015 to October 2018, 717 patients with RA and 717 healthy controls who were treated or performed physical examination in Tianjin First Central Hospital were enrolled in this study. The basic disease diagnoses were recorded. A questionnaire was performed on all participants to assess the demographic details of the RA cohort. Moreover, laboratory indicators related to glucose and lipid metabolism in patients with RA were also detected. The potential risk factors for MetS were also analyzed. RESULTS: The prevalence of MetS were 31.2% and 34.2% in case and control groups, respectively (P = .22). There were lower levels of HDL-C, obesity, TG, LDL-C and TC in case group than control group (all P < .05). The hypertension levels in healthy controls was decreased in compared with patients with RA (P < .05). Nevertheless, in patients with RA, complement 3 (OR: 1.02; 95% CI: 1.01-1.03, P = .007) and less glucocorticoids use (OR: 0.63, 95% CI: 0.39-0.99, P = .046) were associated with MetS. CONCLUSION: The prevalence of MetS was not associated with RA. Complement 3 may be associated with the higher prevalence of MetS in patients with RA. Glucocorticoids treatment may be associated with MetS.

Serum progranulin level is associated with disease activity following orthopedic surgery in rheumatoid arthritis patients.

BACKGROUND: Few studies have focused on the ability of progranulin to predict postoperative disease activity in rheumatoid arthritis (RA) patients who have undergone surgery. This study evaluated serum progranulin levels in active RA patients and analyzed its relationship with postoperative disease activity. METHODS: One hundred thirty-two patients with active RA and 72 healthy subjects were included in this study. Serum progranulin was measured, and clinical data were collected. The postoperative 1-year Disease Activity Score in 28 joints calculated with C-reactive protein (DAS28-CRP) scores was evaluated as an indicator of disease activity. The predictive value of progranulin in postoperative 1-year disease activity in RA patients was also analyzed. RESULTS: Serum progranulin was significantly associated with the postoperative 1-year RA disease activity. The mean serum progranulin level in patients with a high disease activity was significantly higher than that of RA patients with low-to-moderate disease activity (54.2 ± 10.6 ng/mL vs. 46.7 ± 8.8 ng/mL). Serum progranulin was also evaluated as an independent predictive factor for postoperative 1-year RA disease activity in multivariate analysis (odds ratio [OR], 2.21; 95% confidence interval [CI], 1.02-8.85). CONCLUSIONS: Serum progranulin levels may be a promising indicator of postoperative disease activity in RA patients who underwent orthopedic surgery.

Drug screening and identification of key candidate genes and pathways of rheumatoid arthritis.

Rheumatoid arthritis (RA), which normally manifests as a multi­joint inflammatory reaction, is a common immunological disease in clinical practice. However, the pathogenesis of RA has not yet been fully elucidated. Rituximab (RTX) is an effective drug in the treatment of RA, however its therapeutic efficacy and mechanism of action require further investigation. Thus, the present study aimed to screen the candidate key regulatory genes and explain the potential mechanisms of RA. Gene chips of RA and normal joint tissues were analyzed and, gene chips of RTX before and after treatment were investigated. In the present study, strong evidence supporting the pathogenesis of RA and mechanism of action of RTX were also revealed. Differentially expressed genes (DEGs) were analyzed using the limma package of RStudio software. A total of 1,150 DEGs were detected in RA compared with normal joint tissues. The upregulated genes were enriched in 'interleukin­12 production', 'I­κB kinase/NF­κB signaling', 'regulation of cytokine production involved in immune response' and 'cytokine metabolic process'. Functional enrichment analysis showed that RTX was primarily involved in the inhibition of 'adaptive immune response', 'B cell activation involved in immune response' and 'immune effector process'. Subsequently, leukocyte immunoglobulin­like receptor subfamily B member 1 (LILRB1), a hub gene with high connectivity degree, was selected, and traditional Chinese medicine libraries were molecularly screened according to the structure of the LILRB1 protein. The results indicated that kaempferol 3­O­ß­D­glucosyl­(1→2)­ß­D­glucoside exhibited the highest docking score. In the present study, the DEGs and their biological functions in RA and the pharmacological mechanism of RTX action were determined. Taken together, the results suggested that LILRB1 may be used as a molecular target for RA treatment, and kaempferol 3­O­ß­D­glucosyl­(1→2)­ß­D­glucoside may inhibit the pathological process of RA.

Analysis of kinematic behavior of pedestrians/cyclists in vehicle collisions using impulse.

Objective: In order to further reduce the injury risks to pedestrians/cyclists in vehicle collisions, it is necessary to control pedestrian/cyclist kinematics. To investigate pedestrian/cyclist kinematic behavior from initial contact with the vehicle to the ground contact, it is necessary to evaluate the force interactions between the pedestrian/cyclist body region and the car body during the crash event.Method: Finite element analysis was conducted for models of pedestrians and cyclists being struck by a car around the center, left, and right sides of the front of the vehicle at 40 km/h. The impulse that was applied to each body region of the pedestrian/cyclist by the vehicle body during the impact was employed to analyze the kinematic behavior of the pedestrian/cyclist.Results: An impulse-time history can be separated into three stages. In the first stage, the pedestrian/cyclist was accelerated by the vehicle's forward impulse imparted to the subject due to the lower extremities contacting the bumper and hood leading edge. In the second stage, the pedestrian/cyclist rotates around the hood leading edge. In the third stage, the pedestrian/cyclist was accelerated in the vehicle forward and upward directions by the impulse resulting from the contact of the head and upper extremities with the cowl and the windshield. As the impulse to the lower extremity increased, the wraparound distance (WAD) decreased; however, the pelvis velocity in the forward direction increased.Conclusion: This research employed a new approach using the impulse transmitted to each body region due to contact with the vehicle body and showed that impulse is a useful parameter to understand the process of pedestrian/cyclist kinematics. The impulse relates to the linear and angular velocities of the pedestrian/cyclist at the time of separation from the car, thereby providing useful information to control pedestrian/cyclist falling kinematics prior to the ground impact.

Active vitamin D activates chondrocyte autophagy to reduce osteoarthritis via mediating the AMPK-mTOR signaling pathway.

Osteoarthritis (OA) is a common joint degenerative disease. Vitamin D (VD) is essential for bone health. We hypothesized that active VD could be used as a therapeutic treatment for OA. Low serum levels of 25-hydroxyvitamin D [25(OH)D] have been found in patients with OA, and thus the serum level of VD could be diagnostic of OA. To test this, we established a mouse model of OA. The results from staining with hematoxylin-eosin and Safranin O - Fast Green indicated that active VD reduced the symptoms of OA in mice. The results from Western blotting indicated that treatment with VD increased the activity of the p-AMPK-AMPK signaling pathway and decreased the p-mTOR-mTOR pathway; it also increased the ratio of LC3II:LC3I antibodies and the protein expression levels of Beclin-1, but decreased the level of p62. Further, treatment with VD reduced the levels of tumor necrosis factor-α and interleukin-6 both in cartilage tissues and in chondrocytes. Administration of the AMPK inhibitor compound C and autophagy inhibitor 3-methyladenine (3-MA) reversed these changes following VD treatment. In addition, the results from transfection with mRFP-GFP-LC3 indicated that active VD led to autophagosome aggregation in OA chondrocytes. 3-MA inhibited cell autophagy and promoted inflammation in OA. This study provides evidence that active VD activate chondrocyte autophagy to reduce OA inflammation via activating the AMPK-mTOR signaling pathway. Treatment with active VD could be a novel therapeutic option for OA.

Logistic regression analysis of pedestrian casualty risk in passenger vehicle collisions in China.

A large number of pedestrian fatalities were reported in China since the 1990s, however the exposure of pedestrians in public traffic has never been measured quantitatively using in-depth accident data. This study aimed to investigate the association between the impact speed and risk of pedestrian casualties in passenger vehicle collisions based on real-world accident cases in China. The cases were selected from a database of in-depth investigation of vehicle accidents in Changsha-IVAC. The sampling criteria were defined as (1) the accident was a frontal impact that occurred between 2003 and 2009; (2) the pedestrian age was above 14; (3) the injury according to the Abbreviated Injury Scale (AIS) was 1+; (4) the accident involved passenger cars, SUVs, or MPVs; and (5) the vehicle impact speed can be determined. The selected IVAC data set, which included 104 pedestrian accident cases, was weighted based on the national traffic accident data. The logistical regression models of the risks for pedestrian fatalities and AIS 3+ injuries were developed in terms of vehicle impact speed using the unweighted and weighted data sets. A multiple logistic regression model on the risk of pedestrian AIS 3+ injury was developed considering the age and impact speed as two variables. It was found that the risk of pedestrian fatality is 26% at 50 km/h, 50% at 58 km/h, and 82% at 70 km/h. At an impact speed of 80 km/h, the pedestrian rarely survives. The weighted risk curves indicated that the risks of pedestrian fatality and injury in China were higher than that in other high-income countries, whereas the risks of pedestrian casualty was lower than in these countries 30 years ago. The findings could have a contribution to better understanding of the exposures of pedestrians in urban traffic in China, and provide background knowledge for the development of strategies for pedestrian protection.