LKB1 and CRMP1 cooperatively promote the repair of the sciatic nerve injury.

After peripheral nervous system injury, Schwann cells (SCs) can repair axons by providing a growth-promoting microenvironment. The aim of this study is to explore the effects and mechanisms of LKB1 and CRMP1 on the repair of sciatic nerve injury (SNI). The expressions of LKB1 and CRMP1 were changed in rats with SNI from 12 h to 4 weeks by hematoxylin-eosin staining, RT-PCR assay, immunohistochemical staining, and western blotting. Immunofluorescence results show that LKB1 and CRMP1 are co-localized in the regenerated axons of the sciatic nerve tissue of SNI rats. Co-immunoprecipitation indicates that LKB1 interacts with CRMP1. LKB1 interference suppresses the phosphorylation level of CRMP1. Overexpression of LKB1 and CRMP1 promotes the invasion and migration of SCs, and nerve cell protuberance extends. The structure of the myelin sheath in the sciatic nerve of the model group was found to be loose and disordered. Rats in the model group had higher pain thresholds and heat sensitivity response times than those in the control group. Nerve conduction velocity, the latency of action potential, and the peak value of compound muscle action potential in the SNI group were significantly lower than those in the control group, and the muscle atrophy was severe. Overexpression of LKB1 may significantly improve the above conditions. However, the function of LKB1 to improve SNI is abolished by the interference of CRMP1. In summary, the interaction between LKB1 and CRMP promotes the migration and differentiation of SCs and the extension of neurons, thereby improving the repair of nerve injury.

Role of Iron Accumulation in Osteoporosis and the Underlying Mechanisms.

Osteoporosis is prevalent in postmenopausal women. The underlying reason is mainly estrogen deficiency, but recent studies have indicated that osteoporosis is also associated with iron accumulation after menopause. It has been confirmed that some methods of decreasing iron accumulation can improve the abnormal bone metabolism associated with postmenopausal osteoporosis. However, the mechanism of iron accumulation-induced osteoporosis is still unclear. Iron accumulation may inhibit the canonical Wnt/ß-catenin pathway via oxidative stress, leading to osteoporosis by decreasing bone formation and increasing bone resorption via the osteoprotegerin (OPG)/receptor activator of nuclear factor kappa-B ligand (RANKL)/receptor activator of nuclear factor kappa-B (RANK) system. In addition to oxidative stress, iron accumulation also has been reported to inhibit either osteoblastogenesis or osteoblastic function as well as to stimulate either osteoclastogenesis or osteoclastic function directly. Furthermore, serum ferritin has been widely used for the prediction of bone status, and nontraumatic measurement of iron content by magnetic resonance imaging may be a promising early indicator of postmenopausal osteoporosis.

A novel method of manual positioning based on anatomical mark (shoulder-to-shoulder) to prevent postoperative leg-length discrepancy for femoral neck fractures in hip arthroplasty.

Objective: To determine whether the two lower extremities are of equal length after hip arthroplasty for femoral neck fractures, we developed a novel method of manual positioning based on anatomical mark (shoulder-to-shoulder) in hip arthroplasty. Methods: Patients with femoral neck fractures requiring hip arthroplasty from July 2020 to March 2022 in the orthopedic department of Jinjiang Municipal Hospital, Fujian Province, China were recruited. Hip arthroplasty was performed using the proposed "shoulder-to-shoulder" method of manual positioning based on anatomical mark in 52 patients with femoral neck fractures who met the inclusion criteria. "Shoulder-to-shoulder" was achieved by alignment of the marked femoral "shoulder" and the "shoulder" of prosthesis stem. There were 16 male and 36 female patients, with 27 undergoing total hip arthroplasty (THA) and 25 undergoing hip hemiarthroplasty (HA). The fractures were categorized according to the Garden classification: type II, type III, and type IV in 5, 11, and 36 patients, respectively. The vertical distance from the apex of the medial margin of the femoral trochanter to the tear drop line on both sides which was regarded as the length of both limbs were compared via postoperative imaging, and the apex-shoulder distance on the ipsilateral side measured via postoperative imaging was compared with those measured intraoperatively. Results: All patients completed the surgery successfully. The measurement results for the lower extremities after THA were as follows: contralateral group, 43.87 ± 5.59 mm; ipsilateral group, 44.64 ± 5.43 mm. The measurement results for the lower extremities after HA were as follows: contralateral group, 45.18 ± 7.82 mm; ipsilateral group, 45.16 ± 6.43 mm. The measurement results for the lower extremities after all arthroplasties were as follows: contralateral group, 44.50 ± 6.72 mm; ipsilateral group, 44.89 ± 5.90 mm. The results for the apex-shoulder distance were as follows: postoperative imaging, 19.44 ± 3.54 mm; intraoperative apex-shoulder distance, 27.28 ± 2.84 mm. Statistical analysis results indicated no statistically significant difference in the postoperative bilateral lower extremity length after hip arthroplasty (P = 0.75), while a statistically significant difference was found between the intraoperative and postoperative imaging measurements of the apex-shoulder distance (P < 0.01). Conclusion: The novel method of manual positioning based on anatomical mark (shoulder-to-shoulder) for femoral neck fractures in hip arthroplasty is simple and accurate, making it effective for preventing postoperative bilateral leg length discrepancy.

Efficacy of Yigu® versus Aclasta® in Chinese postmenopausal women with osteoporosis: a multicenter prospective study.

Zoledronic acid (ZOL) is a therapy inhibiting bone resorption. In this study, generic ZOL (Yigu®) showed its clinical efficacy consistency with original ZOL (Aclasta®) in Chinese postmenopausal women with osteoporosis. This study provides a practical basis for the application of Yigu® in Chinese population. INTRODUCTION: Yigu® has been approved its bioequivalence to Aclasta®. However, the clinical efficacy and safety of Yigu® have not been evaluated yet. Here, we compared the effectiveness and safety between Yigu® and Aclasta® in Chinese postmenopausal women with osteoporosis and assessed the efficacy of intravenous infusion of ZOL. METHODS: This was a randomized open-label, active-controlled study in postmenopausal women with osteoporosis of 14 clinical centers in China. Postmenopausal women with osteoporosis were recruited and randomized to receive a single infusion of 5 mg Yigu® or Aclasta®. The primary endpoint was the percentage change in bone mineral density (BMD) at lumbar spine after 12 months of treatment and was assessed for equivalence. The secondary endpoint was the percentage change in BMD at proximal femur after 12 months. Additional secondary endpoints were percentage changes in BMD at the above sites after 6 months of treatment and changes in bone turnover biomarkers during ZOL treatment. Safety was also evaluated and compared between two groups. RESULTS: A total of 458 postmenopausal women with osteoporosis were enrolled (n = 227, Yigu®; n = 231, Aclasta®). The mean percentage change in the BMD had no statistical difference at the lumbar spine (5.32% vs 5.18%), total hip (2.72% vs 2.83%), and femoral neck (2.37% vs 2.81%) between Yigu® and Aclasta® groups after 12 months of treatment. The mean difference of BMD change at the lumbar spine after 12 months between two groups was 0.15% (95% CI: - 0.71 to 1.00, equivalence margin: - 1.5%, 1.5%), demonstrating the treatments were equivalent. Meanwhile, the decreases in the P1NP and ß-CTX showed no difference between two groups after 14 days and 6 and 12 months of treatment. As regards the whole sample, BMD significantly increased after 12 months of treatment. Also, serum C-terminal telopeptide of type 1 collagen (ß-CTX) and procollagen 1 N-terminal peptide (P1NP) significantly decreased at each visit period. The overall adverse events were comparable and quite well between two groups. CONCLUSION: Intravenous infusion of zoledronic acid achieved the potent anti-resorptive effects which led to significant increase in BMD of Chinese postmenopausal women with osteoporosis. Yigu® was equivalent to Aclasta® with respect to efficacy and safety.

Iron accumulation deteriorated bone loss in estrogen-deficient rats.

BACKGROUND: Postmenopausal osteoporosis is characterized by an imbalance of bone resorption exceeding bone formation, resulting in a net loss of bone mass. Whether a menopause-related excess of iron contributes to the development of postmenopausal osteoporosis has remained unresolved due to a lack of an appropriate animal model. This study aimed to explore the effects of iron accumulation in bone mass in estrogen-deficient rats. METHODS: In the present study, ovariectomy (OVX) was performed in female rats and the changes of iron metabolism and some related modulated genes were detected. Ferric ammonium citrate (FAC) was used as a donor of iron for OVX rats. Moreover, micro-CT was performed to assess the bone microarchitecture in sham group, OVX, and FAC groups. Histological detection of iron in liver was assessed by Perl's staining. The expressions of ß-CTX and osteocalcin were assessed by ELISA. RESULTS: It was found that serum iron decreased after OVX. It was found that the expressions of Hepcidin in liver and Fpn, DMT-1 in duodenum significantly decreased at transcriptional level in OVX group than sham group. However, no difference existed in the expression of DMT-1. Then, ferric ammonium citrate (FAC) was used as a donor of iron for OVX rats. The FAC group manifested significant iron accumulation by increased serum iron and hepatic iron content. In addition, FAC treatment accelerated bone loss and decreased BMD and biomechanics in OVX rats. Moreover, bone biomarker ß-CTX rather than osteocalcin increased significantly in FAC groups than OVX group. CONCLUSIONS: In conclusion, no iron accumulation occurred in OVX rats. Furthermore, iron accumulation could further deteriorate osteopenia through enhanced bone resorption.

miRNA-296-5p functions as a potential tumor suppressor in human osteosarcoma by targeting SND1.

BACKGROUND: The pathogenesis of osteosarcoma (OS) is still unclear, and it is still necessary to find new targets and drugs for anti-OS. This study aimed to investigate the role and mechanism of the anti-OS effects of miR-296-5p. METHODS: We measured the expression of miR-296-5p in human OS cell lines and tissues. The effect of miR-296-5p and its target gene staphylococcal nuclease and tudor domain containing 1 on proliferation, migration, and invasion of human OS lines was examined. The Student's t test was used for statistical analysis. RESULTS: We found that microRNA (miR)-296-5p was significantly downregulated in OS cell lines and tissues (control vs. OS, 1.802 ±â€Š0.313 vs. 0.618 ±â€Š0.235, t = 6.402, P < 0.01). Overexpression of miR-296-5p suppressed proliferation, migration, and invasion of OA cells. SND1 was identified as a target of miR-296-5p by bioinformatic analysis and dual-luciferase reporter assay. Overexpression of SND1 abrogated the effects induced by miR-296-5p upregulation (miRNA-296-5p vs. miRNA-296-5p + SND1, 0.294 ±â€Š0.159 vs. 2.300 ±â€Š0.277, t = 12.68, P = 0.003). CONCLUSION: Our study indicates that miR-296-5p may function as a tumor suppressor by targeting SND1 in OS.

Iron accumulation regulates osteoblast apoptosis through lncRNA XIST/miR-758-3p/caspase 3 axis leading to osteoporosis.

Postmenopausal osteoporosis (PMOP) is mainly caused by multiple factors. Recent studies have suggested that iron accumulation (IA) was closely related to PMOP. However, the detailed molecular mechanisms have not been well demonstrated. We constructed the IA mouse model by intraperitoneal injections of ferric ammonium citrate (FAC) and cell model by culturing with the medium containing FAC. Osteoporosis was confirmed in mouse bone tissues using H&E staining, and the level of serum ferritin, alkaline phosphatase (ALP), procollagen-1 N-terminal peptide (P1NP), and osteocalcin in mice was examined by ELISA. The expressions of XIST and miR-758-3p were detected by qRT-PCR. Cell proliferation and apoptosis were measured by CCK-8, TUNEL, and flow cytometry. The expression levels of apoptotic-related proteins were evaluated by western blot. Dual luciferase reporter assay was used to examine the molecular interaction. The expressions of ALP, P1NP, and osteocalcin, and the H&E staining of bone tissues in mice were analyzed to confirm the biological function of XIST and miR-758-3p in vivo. XIST was up-regulated while miR-758-3p was down-regulated in IA mouse and cell models. XIST knockdown significantly reduced FAC-induced osteoblast apoptosis, which was mimicked by transfection with miR-758-3p mimics. XIST acted as a sponge of miR-758-3p, which targeted caspase 3. IA led to the high expression of XIST and promoted osteoblast apoptosis through miR-758-3p/caspase 3. Transfection with shXIST or miR-758-3p mimics alleviated IA-induced mouse osteoporosis. IA regulated osteoblast apoptosis through XIST/miR-758-3p/caspase 3 axis, which might provide alternative targets for the treatment of osteoporosis.

[Comparison of measurement methods of lower limb length in hip arthroplasty for femoral neck fracture].

OBJECTIVE: To compare the accuracy of three methods for measuring the length of both lower limbs in hip arthroplasty for femoral neck fracture in the elderly, and to introduce a "shoulder to shoulder" anatomical location marking method for femur. METHODS: From January 2017 to January 2019, 90 elderly patients with femoral neck fracture were treated with hip replacement, including 39 males and 51 females, aged 65 to 96(78.0±7.4) years, 56 cases of total hip and 34 cases of hemi hip. According to garden classification, there were 7 cases of typeⅡ, 63 cases of type Ⅲ and 20 cases of type Ⅳ. The patients were divided into three groups according to different measurement methods:contralateral contrast method (group A) of 19 cases, shuck test method (group B) of 28 cases, and "shoulder to shoulder" anatomical marker localization method (Group C) of 43 cases. The accuracy of the three methods was compared by measuring the length difference of lower limbs in vitro and imaging. RESULTS: All patients completed the operation successfully. After total hip arthroplasty, the length of lower limbs in group A was(12.9±8.6) mm, and that in group B was(10.3±4.4) mm. After hemiarthroplasty, the length of lower limbs in group A was (13.2±7.2) mm, group B was (8.7±3.5) mm, and group C was (6.3±2.8) mm; the measurement results of unequal length of lower limbs after total hip arthroplasty were(12.9±8.1) mm in group A, (9.6±4.0) mm in group B and (6.6±2.6) mm in group C. The results of factorial analysis of variance showed that the differences among the three groups were statistically significant (F=9.763, P<0.01). The difference between two groups showed that the length of lower limbs in group A and group B was higher than that in group C(P<0.05). There was no significant differencebetween total hip arthroplasty and hemiarthroplasty (F=0.270, P=0.605). Three different intraoperative measurement methods for postoperative lower limb length difference were group C

[Study on changes of coagulation state, microthrombus and vascular density in the model of iron accumulation osteoporosis].

OBJECTIVE: To understand changes of coagulation state, microthrombus, microvascular bed and bone density in the osteoporosis model of iron accumulation, and explore the influence of iron accumulation in aspects of osteoporosis on coagulation function and blood vessels. METHODS: Tewnty-four male SPF SD rats aged 6 months were selected, which with the average body weight (250±20) g, which were divided into control group and iron accumulation group according to random number table, 12 rats in each group. Iron accumulation group was intervened by intraperitoneal injection of ferric ammonium citrate 90 mg / kg, and control group was intraperitoneally injected with equal volume of normal saline, twice a week for 9 weeks. After intervention, serum ferritin, coagulation function, microthrombus, vascular density, and three-dimensional morphological reconstruction and spatial structure parameters of the distal femur trabeculae were measured and statistically analyzed. RESULTS: Serum ferritin of iron accumulation group (136.36±35.41) µg / L was higher than control group (68.44±16.86) µg / L(P<0.05). Bone mineral density (BMD) of iron accumulation group (0.167±0.024) g / cm3 was lower than control group(0.400±0.030)g / cm3. Fibrinogen of iron accumulation group (2.03±0.13) g / L was increased than that of control group (1.78±0.46) g / L, D-dimer contents of iron accumulation group (534.95±31.81) ng /ml was increased than that of control group (329.02±84.99) ng /ml, while thrombin time (39.64±2.18) s and prothrombin time(8.70±0.39) s of iron accumulation group were shorter than that of control group (44.92±2.98) s, (9.44±0.49) s (P<0.05). After ink staining, microvessel density in iron accumulation group (17.46±2.07)% was significantly reducedcompared with that of control group(23.81±2.98)%(P<0.05). HE and MSB staining which showed microthrombus in bone marrow of iron accumulation rats, as well as microthrombus in myocardium. CONCLUSION: In the osteoporosis model with the influence of iron accumulation, iron accumulation had a significant influence on the coagulation function, and the blood was relatively hypercoagulable. The bone vascular bed uas reduced, and there were microthrombus in the bone marrow. Hypercoagulable state of blood and formation of microthrombi may be important factors influencing the occurrence of iron accumulation osteoporosis.

Bone Microthrombus Promotes Bone Loss in Iron Accumulation Rats.

In the present study, we investigated the changes of the coagulation state, bone microthrombus, microvascular bed and bone density levels in iron accumulation rats. Meanwhile,the effect of anticoagulation therapy on bone mineral density was further investigated. We established two groups: a control (Ctrl) group and an iron intervention (FAC) group. Changes in coagulation function, peripheral blood cell counts, bone microthrombus, bone vessels and bone mineral density were compared between the two groups. We designed the non-treatment group and treatment group to study the changes of bone mineral density by preventing microthrombus formation with the anticoagulant fondaparinux. We found that the fibrinogen and D-dimer contents were significantly higher, whereas the thrombin time (TT) and prothrombin time (PT) were significantly shorter in the FAC group. After ink staining, the microvascular bed in the FAC group was significantly reduced compared with that in the Ctrl group. HE and Martius Scarlet Blue (MSB) staining showed microthrombus in the bone marrow of the iron accumulation rats. Following anticoagulation therapy, the bone microcirculation vascular bed areas in the treatment group rats were significantly increased. Furthermore, the bone mineral density was increased in the treatment group compared with that in the non-treatment group. Through experiments, we found that the blood in iron accumulation rat was relatively hypercoagulable; moreover, there was microthrombus in the bone marrow, and the bone vascular bed was reduced. Additionally, anticoagulation was helpful for improving bone microcirculation, reducing microthrombus and decreasing bone loss.

[Percutaneous pedicle screw fixation combined with vertebroplasty for the treatment of Genant â ¢ degree osteoporotic vertebral compression fractures].

OBJECTIVE: To investigate the clinical effect of percutaneous pedicle screw fixation(PPSF) combined with percutaneous vertebroplasty (PVP) in the treatment of Genant Ⅲ degree osteoporotic vertebral compression fractures (OVCFs). METHODS: The hospitalized 83 patients with Genant Ⅲ degree OVCFs treated by PPSF combined with PVP from June 2015 to June 2017 were retrospectively analyzed, and 83 patients treated by PVP alone from January 2013 to June 2016 were randomly selected as the control group. There were 19 males and 64 females with an average age of (73.6±11.0) years in combined group with treatment of PPSF and PVP. There were 15 malesand 68 females with an average age of (75.5±10.6) years in control group. The anterior edge height of the vertebral body and Cobb angle before operation, 1 day, and 6, 12, 24 months after operation were compared between two groups. Visual analogue scale(VAS) and Oswestry Disability Index (ODI) were used to assess the pain level and daily lumbar dysfunction for patients, respectively. The complications were observed. RESULTS: The follow-up time of all patients was more than 2 years. The combined group and control group were (24.3±10.2) months and (27.5±14.8) months, respectively. There were no statistically significant differences in the anterior edge height of the vertebral body and Cobb angle at 1 day after surgery between two groups (P>0.05), and there were statistically significant differences at 6, 12, 24 months after surgery between two groups (P<0.01). The difference in ODI and VAS scores at 6 and 12 months after operation between two groups was statistically significant (P<0.05). Postoperative complications incontrol group were higher than those in the combined group. CONCLUSION: PPSF combined with PVP for the treatment of Genant Ⅲ degree OVCFs is superior to PVP alone in terms of vertebral height loss, patient satisfaction, and complications.

Arthroscopic repair of partial articular supraspinatus tendon avulsion lesions by conversion to full-thickness tears through a small incision.

PURPOSE: To assess the clinical efficacy of converting partial articular supraspinatus tendon avulsion (PASTA) lesions to full-thickness tears through a small local incision of the bursal-side supraspinatus tendon followed by repair. METHODS: We retrospectively analyzed 41 patients with Ellman grade 3 PASTA lesions and an average age of (54.7 ± 11.4) years from March 2013 to July 2017. Patients without regular conservative treatment and concomitant with other shoulder pathologies or previous shoulder surgery were excluded from the study. The tears were confirmed via arthroscopy, and a polydioxanone suture was placed to indicate the position of each tear. A small incision of approximately 6 mm was made using a plasma scalpel on the bursal-side supraspinatus tendon around the positioned suture to convert the partial tear into a full-thickness tear. The torn rotator cuff was sutured through the full thickness using a suture passer after inserting a 4.5-mm double-loaded suture anchor. Data were analyzed using a paired Student's t-test with statistical significance defined as p <0.05. RESULTS: At the final follow-up of 2 years, the pain-free shoulder joint range of motion and visual analog scale score were significantly improved compared to those before surgery (p < 0.001). The postoperative American Shoulder and Elbow Surgeons shoulder score was (90.6 ± 6.2), which was significantly higher than the preoperative score of (47.9 ± 8.3) (p < 0.001). The University of California at Los Angeles shoulder rating scale score increased from (14.7 ± 4.1) prior to surgery to (32.6 ± 3.4) points after surgery (p < 0.001). No patient had joint stiffness. CONCLUSION: This modified tear completion repair, by conversion to full-thickness tears through a small incision, has less damage to the supraspinatus tendon on the side of the bursa compared to traditional tear completion repair in the treatment of PASTA lesions. This surgical method is a simple and effective treatment that can effectively alleviate pain and improve shoulder joint function.

MiR-708 inhibits MC3T3-E1 cells against H2O2-induced apoptosis through targeting PTEN.

BACKGROUND: The dysregulation of proliferation and apoptosis plays a significant role in the pathogenesis of postmenopausal osteoporosis (PO). MicroRNAs play an important role in regulating apoptosis of MC3T3-E1 cells. However, the role and potential mechanism of miR-708 for regulating H2O2-induced apoptosis is unknown. This study aimed to investigate the protective function of miR-708 in H2O2-induced apoptosis of MC3T3-E1 osteoblasts. METHODS: MC3T3-E1 was co-cultured with H2O2 for 8 h, then, flow cytometry, malondialdehyde (MDA), and glutathione peroxidase (Gpx) levels were measured to establish the oxidative model. MiRNA microarray was performed to assess differentially expressed miRNAs between control and H2O2-treated MC3T3-E1 cells. We then performed RT-PCR to identify the relative expression of miR-708 and PTEN. After transfected MC3T3-E1 with miR-708 mimics, flow cytometry, MDA, and Gpx level were performed to identify the apoptosis rate and oxidative stress in these groups. Furthermore, we small interfering RNA of PTEN to identify the role of PTEN in H2O2-induced apoptosis of MC3T3-E1 cells. RESULTS: H2O2 (100 nM) could significantly induce the apoptosis of MC3T3-E1 cells. Moreover, H2O2 could significantly increase the MDA level and downregulated Gpx level. RT-PCR found that H2O2 significantly decrease the level of miR-708. Compared with H2O2 group, H2O2 + miR-708 mimic significantly decreased the apoptosis rate. CONCLUSIONS: miR-708 plays a protective role in H2O2-induced MC3T3-E1 osteoblasts apoptosis and its protective effect is proceeded by regulating ROS level and PTEN expression level.

Ferric Ion Induction of Triggering Receptor Expressed in Myeloid Cells-2 Expression and PI3K/Akt Signaling Pathway in Preosteoclast Cells to Promote Osteoclast Differentiation.

OBJECTIVE: Iron plays a significant role in multiple biological processes. The purpose of this study was to measure whether iron mediated osteoclast differentiation through regulation of triggering receptor expressed in myeloid cells-2 (Trem-2) expression and the PI3K/Akt signaling pathway. METHODS: The effects of six different concentrations of ferric ammonium citrate (FAC) (100, 80, 40, 20, 10 and 0 µmol/L) on RAW 264.7 cells proliferation were assessed by Cell Counting Kit-8 (CCK-8) gassay. Tartrate resistant acid phosphatase (TRAP) assay was performed to detect the effects of FAC on osteoclast formation. The expression of osteoclast differentiation-related (TRAP, NFATc-1, and c-Fos) and Trem-2 mRNA and proteins was analyzed by reverse transcription-polymerase chain reaction and western blot, respectively. Si-Trem-2 was constructed and transfected to RAW264.7 to measure the effects of Trem-2 on FAC-mediated osteoclast formation. TRAP assay and osteoclast differentiation-related gene analyses were further performed to identify the role of Trem-2 in osteoclastogenesis. The Search Tool for the Retrieval of Interacting Genes (STRING) was used to explore the target genes of Trem-2. Trem-2-related gene ontology and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were used for further in-depth analysis. PI3K/Akt pathway-related proteins were detected by immunofluorescence and western blot. RESULTS: In groups with FAC concentration of 10 (102.5 ± 3.1), 20 (100.5 ± 1.5), and 40 µmol/L (98.7 ± 3.1), compared with the control group (100.1 ± 2.2), cell viability was not significantly different from the control (P > 0.05). When the concentration of FAC exceeded 80 µmol/L, cell viability was significantly decreased (87.5 ± 2.8 vs 100.1 ± 2.2, P < 0.05). FAC promotes Trem-2 expression and osteoclast differentiation in a dose-response manner (P < 0.05). The number of osteoclast-like cells was found to be reduced following transfection with the siRNA of Trem-2 (42 ± 3 vs 30 ± 5, P < 0.05). We observed that most of Trem-2 target genes are primarily involved in response to organic substance, regulation of reactive oxygen species metabolic process, and regulation of protein phosphorylation. The STRING database revealed that Trem-2 directly target two gene nodes (Pik3ca and Pik3r1), which are key transcriptional cofactors of the PI3K/Akt signaling pathway. KEGG pathways include the "PI3K-Akt signaling pathway," the "thyroid hormone signaling pathway", "prostate cancer," the "longevity regulating pathway," and "insulin resistance." Expression of p-PI3K and p-Akt protein, measured by immunofluorescence and western blotting, was markedly increased in the FAC groups. Trem-2 siRNA caused partial reduction of these two proteins (p-PI3K and p-Akt) compared to the FAC alone group. CONCLUSION: The FAC promoted osteoclast differentiation through the Trem-2-mediated PI3K/Akt signaling pathway. However, its regulation osteoclastogenesis should be verified through further in vivo studies.

Cnidium lactone prevents bone loss in an ovariectomized rat model through the estrogen-α/BMP-2/Smad signaling pathway.

BACKGROUND: The present study aimed to investigate the effect of cnidium lactone on ovariectomy (OVX)-induced bone loss and determine whether it exerts its effects by mediating the estrogen receptor-α (ERα)/bone morphogenetic protein-2 (BMP-2)/Smad signaling pathways. METHODS: Fifty-five female rats were randomly assigned to the following treatment groups: the OVX group, the sham-operated (sham) group, and groups treated with cnidium lactone at different doses (10 mg/kg/day, 20 mg/kg/day, 30 mg/kg/day). Treatments were administered for 60 days. Search Tool for Interacting Chemicals (STITCH; http://stitch.embl.de) was used to identify the interaction between cnidium lactone and target proteins. Bone mineral density (BMD), mechanical strength, serum osteoblastic and osteoclastic markers, and hematoxylin and eosin (HE) staining of the distal femur were evaluated. Moreover, western blot analyses were also performed to evaluate the effect of cnidium lactone on the ERα/BMP-2/Smad signaling pathway. RESULTS: Cnidium lactone treatment was associated with an increase in the BMD of the distal femur compared to that of the OVX group. Moreover, cnidium lactone significantly increased biomechanical properties in a dose-dependent manner compared to those of the OVX group (p < 0.05). Treatment with cnidium lactone significantly enhanced the BMP-2/Smad signaling pathway by up-regulating the expression of ERα, BMP-2, p-Smad1 and p-Smad4. Cnidium lactone treatment improved the microstructure of trabecular bone in the distal femurs of OVX rats, as shown by HE staining. CONCLUSIONS: Cnidium lactone exerts potent antiosteoporotic activity in ovariectomized mice, and the underlying molecular mechanism may be related to the ERα/BMP-2/Smad signaling pathways.

Exosomes from adipose­derived stem cells promote chondrogenesis and suppress inflammation by upregulating miR­145 and miR­221.

Osteoarthritis (OA) is one of the most prevalent joint disorders globally. Patients suffering from OA are often obese and adiposity is linked to chronic inflammation. In the present study, the potential of using exosomes isolated from adipose­derived stem cells (ADSCs) as a therapeutic tool for reducing chronic inflammation and promoting chondrogenesis was investigated using patient­derived primary cells. First, it was tested whether patient­derived ADSCs could differentiate into chondrogenic and osteogenic lineages. The ADSCs were then used as a source of exosomes. It was found that exosomes isolated from ADSCs, when co­cultured with activated synovial fibroblasts, downregulated the expression of pro­inflammatory markers interleukin (IL)­6, NF­κB and tumor necrosis factor­α, while they upregulated the expression of the anti­inflammatory cytokine IL­10; without exosomes, the opposite observations were made. In addition, inflammation­inflicted oxidative stress was induced in vitro by stimulating chondrocytes with H2O2. Treatment with exosomes protected articular chondrocytes from H2O2­induced apoptosis. Furthermore, exosome treatment promoted chondrogenesis in periosteal cells and increased chondrogenic markers, including Collagen type II and ß­catenin; inhibition of Wnt/ß­catenin, using the antagonist ICG­001, prevented exosome­induced chondrogenesis. Periosteal cells treated with exosomes exhibited higher levels of microRNA (miR)­145 and miR­221. The upregulation of miR­145 and miR­221 was associated with the enhanced proliferation of periosteal cells and chondrogenic potential, respectively. The present study provided evidence in support for the use of patient­derived exosomes, produced from ADSCs, for potential chondrogenic regeneration and subsequent amelioration of osteoarthritis.

The acromion-greater tuberosity impingement index: A new radiographic measurement and its association with rotator cuff pathology.

PURPOSE: Several radiographic parameters describe humeral head coverage by the acromion. We describe a new radiographic measurement, the acromion-greater tuberosity impingement index (ATI), and its ability to predict rotator cuff pathology. METHODS: The ATI was measured with magnetic resonance imaging (MRI) and X-ray analysis in 83 patients with rotator cuff pathology and 76 patients with acute rotator cuff tears. The lateral acromial angle (LAA), acromion type, the acromion index (AI) and the critical shoulder angle (CSA) were measured to assess their correlations with the ATI. Receiver operating characteristic (ROC) curves were used to predict degenerative rotator cuff pathology. The change in the ATI after acromion surgery was evaluated in both groups. RESULTS: According to the ROC curves, the ATI is a good predictor of degenerative rotator cuff pathology on both X-ray (cut-off, 0.865) and MRI (cut-off, 0.965). Patients with degenerative rotator cuff pathology had a significantly higher average ATI compared to the trauma group (p = 0.001 for X-ray and MRI). The degenerative group had a significantly lower LAA (p = 0.001) and a higher ratio of type III acromion (p = 0.035) than the trauma group. The ATI on X-ray was negatively related to the LAA and positively related to the AI, the CSA and acromion type (each p < 0.05). The ATI on MRI was negatively related to the LAA and positively related to the AI and acromion type (each p <0.05). More patients in the degenerative group than the trauma group needed acromioplasty or acromion decompression (p < 0.05). The ATI on MRI was significantly lower after acromion surgery compared to before surgery in both groups (p < 0.05). CONCLUSION: The ATI is a good predictor of degenerative supraspinatus tendon tears or subacromial impingement syndrome. The ATI on MRI is more accurate and can precisely guide acromion surgery.

[Case-control studies on modified anterolateral approach with modified postmedial approach for the treatment of trimalleolar fractures].

OBJECTIVE: To compare clinical effect of modified anterolateral approach combined with modified posteromedial approach and conventional posterolateral approach combined with medial-aided in treating trimalleolar fractures. METHODS: From January 2015 to August 2017, 108 patients with trimalleolar fractures were enrolled and randomly divided into modified approaches (experimental group) and conventional approaches(control group). There were 53 patients in experimental group including 31 males and 22 females aged from 18 to 67 years old with an average of(40.2±16.4) years old; 19 patients on the left side and 34 patients on the right side; 39 patients were supination external rotation and 14 patients were pronation-external rotation; preoperative waiting time ranged from 6 to 14 d with an average of(9.6±3.1) d; performed operation through modified anterolateral approach combined with modified posteromedial approach. There were 55 patients in control group, including 34 males and 21 females aged from 19 to 69 years old with an average of (42.1±15.3) years old; 18 patients on the left side and 37 patients on the right side; 42 patients were supination external rotation and 13 patients were pronation-external rotation; preoperative waiting time ranged from 7 to 16 d with an average of (10.3±3.4) d; performed operation through conventional posterolateral approach combined with medial-aided. Operation time, intraoperative blood loss, postoperative drainage volume, cases of incision complications and excellent-good reduction, fracture healing time, cases of nerve injury and muscular flexor contracture, cases of incision complications between two groups were compared; AOFAS score were used to evaluate clinical efficacy at 1 year after operation. RESULTS: All patients were followed up from 12 to 24 months with an average of (16.4 ±7.5) months. Operation time, intraoperative blood loss, postoperative drainage volume and incision complication in experimental group were (95.3±22.6) min, (114.7±68.7) ml, (127.5±87.8) ml and 1 case, respectively; while in control group were (112.5±53.8) min, (155.2±79.6) ml, (178.4±73.8) ml and 3 cases respectively; the data in experimental group were better than that of control group. In experimental group, 36 cases got excellent results, 14 good and 3 poor on the quality of reduction, while 30 patients got excellent results, 15 good and 10 poor in control group; the experimental group was better than control group. Fracture healing time in experimental group were(5.5±1.6) months, 2 patients occurred incision complications, while(6.7±2.1) months, 12 patients in control group; the experiment group were better than control group. Postoperative AOFAS score at 12 months in experimental group was 92.9±18.4, and better than control group 80.3±38.3; 32 patients got excellent results, 17 good, 3 moderate and 1 poor in experimental group; 25 patients got excellent results, 18 good, 8 moderate and 4 poor in control group; there was statistical difference between two groups. CONCLUSIONS: Both of modified anterolateral approach combined with modified posteromedial approach and conventional posterolateral approach combined with medial-aided in treating trimalleolar fractures could receive good clinical effect. While compared with conventional posterolateral approach combined with medial-aided, modified anterolateral approach combined with modified posteromedial approach is more fit for blood supply of local soft tissue, and has advantages of less trauma, safety operation and clearly exposure.

Osteoporotic Fracture Guidelines and Medical Education Related to the Clinical Practices: A Nationwide Survey in China.

OBJECTIVES: To investigate the knowledge and practices of Chinese doctors in the management of osteoporotic fractures after the Chinese osteoporotic fracture guidelines update and aseries of medical education in 2017. METHODS: This was a cross-sectional survey of doctors in 71 cities across Mainland China. Based on the 2017 Chinese guidelines for the diagnosis and treatment of osteoporotic fractures, a questionnaire was designed and pre-tested for reliability and validity. Doctors were surveyed with the questionnaire after scientific meetings during February 2017 to January 2018 through WeChat or conference digital platforms or in paper form. Descriptive statistics was used to analyze the responses to the questionnaire. RESULTS: Overall, 314 valid questionnaires were confirmed. Regarding diagnosis, 77% agreed that osteoporosis could be diagnosed once an osteoporotic fracture occurred; 83% believed that the bone mineral density criteria for osteoporosis diagnosis would be T ≤ -2.5 SD. For treatment, almost all (99.7%) agreed with anti-osteoporosis treatment being one of the basic principles of osteoporotic fracture treatment; 71.6% considered bisphosphonates as the most commonly used anti-osteoporosis drug; 97% believed that patients who have used anti-osteoporosis drugs should reassess osteoporosis after osteoporotic fractures instead of discontinue; 95% thought that the patients who did not use anti-osteoporosis medications before osteoporotic fracture should be treated with anti-osteoporosis drugs after fracture treatment as early as possible; 89% agreed that the standard use of bisphosphonates after osteoporotic fracture would not affect bone healing adversely; 59% believed the course of bisphosphonates treatment for osteoporosis would be 3-5 years, and 27% considered it to be 1-3 years. The patient follow-up rate was poor: 46% selected follow-up rate <30%; only 20% selected follow-up rate >50%. Only 31% of the hospitals had long-term management programs for osteoporotic fractures. CONCLUSIONS: Doctors generally adhered to the updated Chinese guidelines for osteoporotic fractures; frequent participation in medical education can help doctors to increase their awareness of osteoporosis as well as their acceptance and practice of the guidelines.

One-stage reconstruction of complex soft tissue defects in the hands using multidigit, chimeric, lateral arm, perforator flaps.

PURPOSE: To describe our experience using microsurgically fabricated, multilobed, chimeric, lateral arm (LA) flaps to reconstruct hand injuries with complex, multidigit, soft tissue defects and to evaluate the morbidity and esthetic and functional outcomes of the donor sites. METHODS: We performed a single center, retrospective analysis of 21 patients with hand wounds treated from October 2013 to February 2016. All patients underwent reconstruction using multilobed, chimeric, free, LA flaps. A self-reported questionnaire was used to assess donor site morbidity and satisfaction with the esthetic and overall functional result. Outcome measures were the Disabilities of the Arm, Shoulder and Hand (DASH) score, static 2-point discrimination score, and visual analogue scale. RESULTS: The study included 21 patients (20 males and 1 female), with an average age of 32.14 years (range 18-45 years), who sustained traumatic injuries in road traffic accidents (n = 2) or industrial devices (n = 19). The average DASH score was 28.25 ±â€¯2.3, the average 2-PD score was 7.20 ±â€¯1.30, and the average visual analogue scale (VAS) was 0.38 ±â€¯0.40. All 21 patients had sensory disorders at the donor site. Postoperative donor site complications comprised wound dehiscence (n = 1) and hematoma (n = 3). The patient-rated satisfaction score for the donor site was 5.40 ±â€¯0.90, and 70% of the patients would undergo the same surgery again. CONCLUSION: Microsurgical fabrication of multilobed, chimeric, LA flaps can exhibit sensory recovery and minimal pain but may cause hematoma and sensory disorders at the donor site. The flaps are a viable alternative for the reconstruction of complex, multidigit, soft tissue defects of the hands.