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BACKGROUND: Relatively or absolutely active bone resorption function of osteoclasts is one of the causative factors of osteoporosis. Therefore, how to inhibit the formation of osteoclasts and reduce the bone resorption activity is a key element in the prevention and treatment of osteoporosis. Liquiritin, which is derived from licorice, plays a role in the clinical treatment of bone diseases, but there are fewer studies addressing the application of liquiritin in osteoporosis and the mechanism is unknown. OBJECTIVE: To confirm, through both in vivo and in vitro experiments, that liquiritin inhibits osteoclast differentiation and alleviates bone loss. METHODS: Cell counting kit-8 was used to detect whether Liquiritin exerts toxic or proliferative effects on mouse bone marrow-derived macrophages, and tartrate-resistant acid phosphatase staining was performed to observe the effect of liquiritin in inhibiting osteoclast differentiation. The affinity of liquiritin binding to proteins related to osteoclast differentiation was verified by network pharmacology. RT-PCR and western blot assays were performed to detect the inhibitory effects of liquiritin on osteoclast-specific protein and gene expression as well as relevant signaling pathways. Finally, the mitigating effect of liquiritin on bone loss was verified in the C57BL/6J mouse osteoporosis model. RESULTS AND CONCLUSION: Liquiritin, at concentrations of 20 μmol/L and below, could inhibit the formation and differentiation of osteoclasts. Concurrently, it exhibited a high affinity with osteoclast-specific proteins such as nuclear factor of activated T-cells 1, Cathepsin K, c-Fos, and matrix metalloproteinase 9, and reduced the relative expression levels of these genes and proteins. Liquiritin could also effectively lower the phosphorylation expression level of JNK in the MAPK signaling pathway at the 15th, 30th, 45th, and 60th minutes, and it could salvage the degradation of nuclear factor-κB inhibitor α in the nuclear factor-κB signaling pathway at the 60th minute. In vivo experiments demonstrated that liquiritin could mitigate bone loss caused by osteoclasts and improve parameters related to trabecular bone. To conclude, liquiritin possesses the capacity to inhibit osteoclast differentiation and alleviate bone loss, thereby exerting a protective role against osteoporosis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Osteoporosis vertebral compression fracture is a common fracture secondary to osteoporosis, and there is currently a lack of effective predictive indicators and methods for osteoporosis vertebral compression fracture. OBJECTIVE: To investigate the predictive effects of paravertebral muscle degeneration, functional cross-sectional area, and percentage of fat infiltration on osteoporotic vertebral compression fractures. METHODS: The 224 patients with osteoporosis diagnosed from January 2018 to June 2022 were included. They were followed up for more than 2 years. They were divided into fracture group and non-fracture group according to the presence and absence of vertebral fracture. The detailed information of demographics, body mass index, bone mineral density and so on were collected. The functional cross-sectional area and percentage of fat infiltration of bilateral Psoas major muscle and extensor dorsi (Erector spinae muscles muscle and multifidus muscle) at the level of lower endplate of L2 vertebral body were measured and calculated. RESULTS AND CONCLUSION: (1) 224 patients were ultimately included, of which 126 had fractures as the fracture group and 98 had no fractures as the nonfracture group. There was no statistically significant difference in age, gender, height, body mass, body mass index, and fracture segment between the two groups (P > 0.05). (2) The bone mineral density of the fracture group was significantly lower than that of the non-fracture group (P < 0.05). Functional crosssectional areas of Psoas major muscle and extensor dorsi in the fracture group were significantly lower than those in the non-fracture group (P < 0.05). The percentage of fat infiltration of the extensor dorsi in the fracture group was significantly higher than that in the non-fracture group (P < 0.05). There was no significant difference in percentage of fat infiltration of Psoas major muscle between the two groups (P > 0.05). (3) Receiver operating characteristic analysis showed that the vertebral bone mineral density, percentage of fat infiltration of extensor dorsi, functional cross-sectional area of extensor dorsi and percentage of fat infiltration of Psoas major muscle were 0.903 g/cm², 35.426%, 418.875 mm², and 6.375%, respectively. The areas under curve were 0.634, 0.755, 0.876, and 0.585, respectively. (4) These findings indicate that paravertebral muscle degeneration is strongly associated with the occurrence of osteoporotic vertebral compression fractures. The functional cross-sectional area of extensor dorsi muscle can effectively predict the occurrence of osteoporotic vertebral compression fractures, which is helpful for early prevention and treatment of osteoporotic vertebral compression fractures. [ABSTRACT FROM AUTHOR]

BACKGROUND: Osteoporotic vertebral compression fracture is a common fracture secondary to osteoporosis. At present, there is no effective prediction index and method for osteoporotic vertebral compression fracture. OBJECTIVE: To investigate the predictive effect of the comprehensive index of lumbar vertebral body bone strength on osteoporotic vertebral compression fracture. METHODS: 233 patients with osteoporosis were divided into a fracture group and a non-fracture group according to whether a vertebral fracture occurred. The demography, body mass index, vertebral bone mineral density and other details were collected. Lateral X-ray films of the lumbar spine were photographed. The vertebral body width, vertebral body length, sacral slope, pelvic tilt, pelvic incidence, lumbar compressive strength index and the lumbar impact strength index were measured, calculated, and analyzed by univariate and multivariate, and the receiver operating characteristic curve was analyzed. The survival analysis was conducted according to the cut-off value. RESULTS AND CONCLUSION: (1) All patients were followed up for 2-4 years, with an average of 3.1 years. During the follow-up period, 99 cases (38 cases of L1 vertebral body, 61 cases of L2 vertebral body) had fractures (fracture group), and 134 cases (52 cases of L1 vertebral body, 82 cases of L2 vertebral body) had no fractures (non-fracture group). Univariate analysis showed that there was no significant difference in age, sex, height, body mass, body mass index and fracture segment between the two groups (P > 0.05). (2) Lumbar compressive strength index and lumbar impact strength index in the fracture group were lower than those in the non-fracture group (P<0.05). Pelvic incidence and pelvic tilt in the fracture group were higher than those in the non-fracture group (P<0.05). (3) Multivariate analysis showed that lumbar compressive strength index, lumbar impact strength index and pelvic tilt were risk factors for osteoporotic vertebral compression fractures (P<0.05). (4) Receiver operating characteristic curve analysis showed that the cutoff values of vertebral bone mineral density, lumbar compressive strength index, lumbar impact strength index, pelvic tilt and pelvic incidence were 0.913 5 g/cm2, 1.932, 0.903, 21.5° and 55°, respectively; areas under the curve were 0.630, 0.800, 0.911, 0.633 and 0.568, respectively. (5) According to the survival analysis (with osteoporotic vertebral compression fracture as the end point), the average survival time of the patients with lumbar impact strength index ≥0.903 was significantly longer than that of the patients with lumbar impact strength index < 0.903 (P<0.05). (6) These findings conclude that the comprehensive index of lumbar vertebral body bone strength is more accurate than the bone mineral density of the vertebral body and spine-pelvis sagittal parameters in predicting osteoporotic vertebral compression fractures, which is helpful for early prevention and treatment of osteoporotic vertebral compression fractures. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: The majority of studies on developmental dysplasia of the hip focus on hip malformations, but there are few reports on the effects of acetabular dysplasia on the spine. OBJECTIVE: To investigate the compensation of spinopelvic parameters in coronal and sagittal views in patients with developmental dysplasia of the hip, and to explore the correlation between acetabular development and spinopelvic parameters. METHODS: A total of 101 patients with developmental dysplasia of the hip admitted to the Third Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2018 to June 2022 were selected as the trial group, and 114 healthy subjects were selected as the control group during the same period. The spinopelvic parameters of the subjects were measured through the full-length X-ray films of the coronal and sagittal spines: lumbar lordosis, anterior pelvic tilt, thoracolumbar kyphosis, Cobb angle, and the distance between the C7 plumb line and the center sacral vertical line, sacral slope, pelvic incidence, and thoracic kyphosis. The differences in spinopelvic parameters were compared between the two groups. In addition, the differences in spinopelvic parameters in patients with unilateral, bilateral and different Crowe classifications of developmental dysplasia of the hip were compared. Pearson correlation analysis was used to explore the correlation between Sharp angle and spinopelvic parameters. RESULTS AND CONCLUSION: (1) In the sagittal view, the lumbar lordosis in the trial group was significantly lower than that in the control group (P < 0.05). The pelvic tilt and kyphosis angle of the thoracolumbar segment in the trial group were significantly greater than those in the control group (P < 0.05). In the coronary position, the Cobb angle and the distance between the C7 plumb line and center sacral vertical line in the trial group were significantly greater than those in the control group (P < 0.05). There was no significant difference in the remaining spinopelvic parameters between the two groups (P > 0.05). (2) The lumbar lordosis of patients with bilateral developmental dysplasia of the hip was significantly lower than that of patients with unilateral developmental dysplasia of the hip (P < 0.05). The pelvic tilt, thoracolumbar kyphosis, Cobb angle and the distance between the C7 plumb line and center sacral vertical line in bilateral developmental dysplasia of the hip patients were significantly greater than those in unilateral developmental dysplasia of the hip patients (P < 0.05). (3) The lumbar lordosis decreased with the increase of Crowe classification severity (P < 0.05). The pelvic tilt increased with the severity of the Crowe classification (P < 0.05). (4) Pearson correlation analysis showed that Sharp angle was negatively correlated with lumbar lordosis (P < 0.05), while Sharp angle was positively correlated with anterior pelvic tilt, Cobb angle, C7 plumb line and center sacral vertical line (P < 0.05). (5) It is concluded that the pelvic tilt, thoracolumbar kyphosis, Cobb angle and the distance between the C7 plumb line and center sacral vertical line increase, while lumbar lordosis decreases in developmental dysplasia of the hip patients. The degree of acetabular dysplasia was significantly correlated with lumbar lordosis, pelvic tilt, Cobb angle, C7 plumb line and center sacral vertical line. [ABSTRACT FROM AUTHOR]

Copyright of Special Oil & Gas Reservoirs is the property of Special Oil & Gas Reservoirs Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metal Working (1674-165X) is the property of Metal Working Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Vibration Engineering is the property of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For establishing the high reliability load spectrum for transmission shaft of military tracked vehicle on the typical road, the torque and relevant vehicle data similar to that in real service conditions was collected through vehicle experiments, and the confidence level of load data samples was calculated based on the criteria of least testing times. A load spectrum compiling procedure is designed based on 2-D kernel density estimation on account of the irregular 2-D distribution of amplitude and mean values in test load data. In the load spectrum compiling procedure, two times of rain-flow counting are adopted; the first rain-flow counting result is used to deduce the extrema of amplitude and mean values, and the second rain-flow counting result is used to extrapolate the kernel density. This compiling procedure can not only obtain better fitting of amplitude and mean distribution, but also achieve the reasonable extrapolation of the experimental rain-flow matrix. Goodman equation and the equivalent damage conversion method are used to derive 8-level program block load spectrum from 2-D load spectrum, and a loading method for the combination of torque and rotational speed is presented. 0.8 times of eighth amplitude are chosen as the value of small load from the perspective of fatigue damage, and total cycles are decreased by 99. 33% while total damage is decreased only by 0.29% , which can accelerate the fatigue loading test. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)