Microarchitecture Alternations of Osteochondral Junction in Patients with Osteonecrosis of the Femoral Head.

The study was aimed to investigate microarchitecture of osteochondral junction in patients with osteonecrosis of the femoral head (ONFH). We hypothesis that there were microarchitecture alternations in osteochondral junction and regional differences between the necrotic region (NR) and adjacent non-necrotic region(ANR) in patients with ONFH. Femoral heads with ONFH or femoral neck fracture were included in ONFH group (n = 11) and control group (n = 11). Cylindrical specimens were drilled on the NR/ANR of femoral heads in ONFH group and matched positions in control group (CO.NR/ CO.ANR). Histology, micro-CT, and scanning electron microscope were used to investigate microarchitecture of osteochondral junction. Layered analysis of subchondral bone plate was underwent. Mankin scores on NR were higher than that on ANR or CO.NR, respectively (P < 0.001, P < 0.001). Calcified cartilage zone on the NR and ANR was thinner than that on the CO.NR and CO.ANR, respectively (P = 0.002, P = 0.002). Tidemark roughness on the NR was larger than that on the ANR (P = 0.002). Subchondral bone plate of NR and ANR was thicker than that on the CON.NR and CON.ANR, respectively (P = 0.002, P = 0.009). Bone volume fraction of subchondral bone plate on the NR was significantly decreasing compared to ANR and CON.NR, respectively (P = 0.015, P = 0.002). Subchondral bone plate on the NR had larger area percentages and more numbers of micropores than ANR and CON.NR (P = 0.002/0.002, P = 0.002/0.002). Layered analysis showed that bone mass loss and hypomineralization were mainly on the cartilage side of subchondral bone plate in ONFH. There were microarchitecture alternations of osteochondral junction in ONFH, including thinned calcified cartilage zone, thickened subchondral bone plate, decreased bone mass, altered micropores, and hypomineralization of subchondral bone plate. Regional differences in microarchitecture of osteochondral junction were found between necrotic regions and adjacent non-necrotic regions. Subchondral bone plate in ONFH had uneven distribution of bone volume fraction and bone mineral density, which might aggravate cartilage degeneration by affecting the transmission of mechanical stresses.

A forecasting model for suitable dental implantation in canine mandibular premolar region based on finite element analysis.

In recent years, dental implants have become a trend in the treatment of human patients with missing teeth, which may also be an acceptable method for companion animal dentistry. However, there is a gap challenge in determining appropriate implant sizes for different dog breeds and human. In this study, we utilized skull computed tomography data to create three-dimensional models of the mandibles of dogs in different sizes. Subsequently, implants of various sizes were designed and subjected to biomechanical finite element analysis to determine the optimal implant size. Regression models were developed, exploring the relationship between the average weight of dogs and the size of premolar implants. Our results illustrated that the regression equations for mean body weight (x, kg) and second premolar (PM2), third premolar (PM3), and fourth premolar (PM4) implant length (y, mm) in dogs were: y = 0.2785x + 7.8209, y = 0.2544x + 8.9285, and y = 0.2668x + 10.652, respectively; the premolar implant diameter (mm) y = 0.0454x + 3.3506, which may provide a reference for determine suitable clinical implant sizes for dogs.

Clinical phenotypes of comorbidities in end-stage knee osteoarthritis: a cluster analysis.

OBJECTIVES: Comorbidities, as components of these heterogeneous features, often coexist with knee osteoarthritis, and are particularly prevalent in end-stage knee osteoarthritis. Here, we attempted to identify the different clinical phenotypes of comorbidities in patients with end-stage knee osteoarthritis by cluster analysis. METHODS: A total of 421 inpatients diagnosed with end-stage knee osteoarthritis who underwent inpatient surgery were included in this cross-sectional study. 23 demographic, comorbidity, inflammatory immune and evaluation scale variables were collected. Systematic clustering after factor analysis and separate two-step cluster analysis were performed for individual comorbidity variables and all variables, respectively, to objectively identify the different clinical phenotypes of the study patients. RESULTS: Four clusters were finally identified. Cluster 1 had the largest proportion of obese patients (93.8%) and hypertension was common (71.2%). Almost all patients in cluster 2 were depressed (95.8%) and anxiety disorders (94.7%). Cluster 3 combined patients with isolated end-stage knee osteoarthritis and a few comorbidities. Cluster 4 had the highest proportion of patients with rheumatoid arthritis (58.8%). CONCLUSIONS: Patients with end-stage knee osteoarthritis may be classified into four different clinical phenotypes: "isolated end-stage knee osteoarthritis"; "obesity + hypertension"; "depression + anxiety"; and "rheumatoid arthritis", which may help guide individualized patient care and treatment strategies.

IU1 and enzalutamide combination yields synergistic effects on castration-resistant prostate cancer.

BACKGROUND: Androgen deprivation therapy (ADT) is one of the main treatment modalities for prostate cancer (PCa); however, almost all patients treated with ADT eventually progress into castration-resistant PCa (CRPC). Although second-generation androgen receptor (AR) antagonists, such as enzalutamide, have been approved for CRPC treatment, AR signaling in CRPC cells is reactivated through multiple mechanisms, resulting in resistance to treatment and tumor progression with a very poor prognosis. The present study aimed to explore the anticancer effect of a treatment combining AR antagonist enzalutamide with AR degrader IU1 on PCa cells. METHODS: The joint effects of enzalutamide and IU1 on PCa cell proliferation and apoptosis and associated cell signaling were evaluated in vitro. Mechanistically, the ubiquitination level and half-life of AR were examined under the combination treatment. The binding of IU1 and enzalutamide to AR was further verified using cellular thermal shift analysis and isothermal dose-response curve fingerprinting. RESULTS: The combination of IU1 and three AR antagonists showed synergistic effects in different prostate cell lines. IU1 and enzalutamide synergistically promoted the degradation of AR and AR-V7 proteins, as well as suppressed the expression levels of AR and AR-V7 downstream target genes at the transcriptional and protein levels. The combination also synergistically blocked the PCa cell cycle and promoted apoptosis in PCa cell lines. Mechanistically, the combination promoted increased levels of AR ubiquitination. In CRPC cell lines and in the presence of increased androgen concentrations, enzalutamide was still able to bind AR competitively with androgens, reducing the stability of AR and thus promoting the degradation effect of IU1 on AR, synergistically producing an inhibitory effect on PCa cells. CONCLUSION: Taken together, our findings suggest that the combination of AR degrader and enzalutamide potentially represents a new therapeutic strategy for CRPC.

Urinary Exosomal miRNAs as biomarkers of bladder Cancer and experimental verification of mechanism of miR-93-5p in bladder Cancer.

BACKGROUND: Bladder cancer (BC) is one of the most common malignancies globally. Early diagnosis of it can significantly improve patients' survival and quality of life. Urinary exosomes (UEs)-derived miRNAs might be a promising biomarker for BC detection. METHOD: A total of 12 patients with BC and 4 non-cancerous participants (as healthy control) were recruited from a single center between March 2018 and December 2019 as the discovery set. Midstream urine samples from each participants were collected and high-throughput sequencing and differentially expression analysis were conducted. Combined with miRNA expression profile of BC tissue from The Cancer Genome Atlas (TCGA), miRNAs biomarkers for BC were determined. Candidate miRNAs as biomarkers were selected followed by verification with a quantitative reverse-transcription polymerase chain reaction assay in an independent validation cohort consisting of 53 BC patients and 51 healthy controls. The receiver-operating characteristic (ROC) curve was established to evaluate the diagnostic performance of UE-derived miRNAs. The possible mechanism of miRNAs were revealed by bioinformatic analysis and explored in vitro experiments. RESULTS: We identified that miR-93-5p, miR-516a-5p were simultaneously significantly increased both in UEs from BC compared with healthy control and BC tissue compared with normal tissue, which were verified by RT-qPCR in the validation cohort. Subsequently, the performance to discover BC of the miR-93-5p, miR-516a-5p was further verified with an area under ROC curve (AUC) of 0.838 and 0.790, respectively, which was significantly higher than that of urine cytology (AUC = 0.630). Moreover, miR-93-5p was significantly increased in muscle-invasive BC compared with non-muscle-invasive BC with an AUC of 0.769. Bioinformatic analysis revealed that B-cell translocation gene 2(BTG2) gene may be the hub target gene of miR-93-5p. In vitro experiments verified that miR-93-5p suppressed BTG2 expression and promoted BC cells proliferation, invasion and migration. CONCLUSION: Urine derived exosomes have a distinct miRNA profile in BC patients, and urinary exosomal miRNAs could be used as a promising non-invasive tool to detect BC. In vitro experiments suggested that miR-93-5p overexpression may contribute to BC progression via suppressing BTG2 expression.

iTRAQ-based proteomics and in vitro experiments reveals essential roles of ACE and AP-N in the renin-angiotensin system-mediated congenital ureteropelvic junction obstruction.

OBJECTIVE: Ureteropelvic junction obstruction (UPJO) is a common renal obstructive disorder, but its pathogenic mechanisms remain largely unclear. We aimed to investigate the potential involvement of the renin-angiotensin system in congenital UPJO pathogenesis. METHODS: Differentially expressed proteins in exosomes isolated from amniotic fluid of patients with congenital UPJO were characterized using iTRAQ (isobaric tags for relative and absolute quantification)-based proteomics. The expressions of angiotensin-converting enzyme (ACE) and aminopeptidase N (AP-N) in HK2 cells were inhibited by quinapril and siRNA, respectively. Cell proliferation and reactive oxygen species were measured by EdU staining and flow cytometry, respectively. Gene expression was detected by Western blot or qRT-PCR. The inflammatory factors were measured through ELISA. Mice that underwent unilateral ureteral obstruction were used as the animal model. RESULTS: The identity of exosomes from amniotic fluids was confirmed by the expression of CD9 and CD26. In total, 633 differentially expressed proteins were identified in the amniotic fluid-derived exosomes from patients with UPJO, including 376 up- and 257 down-regulated proteins associated with multiple biological processes. Of them, ACE and AP-N were significantly decreased in the amniotic fluid exosomes. Inhibition of ACE and AP-N resulted in suppressed cell proliferation; repressed IARP, AT1R, and MAS1 expression; elevated ROS production; and increased IL-1ß, TNF-α, and IL-6 levels in HK2 cells. Decreased ACE expression and elevated IL-1ß levels were also observed in the mouse model. CONCLUSION: Suppression of ACE and AP-N expression mediates congenital UPJO pathogenesis by repressing renal tubular epithelial proliferation, promoting ROS production, and enhancing inflammatory factor expression.

The Relationship Between Body Mass Index and Bone Mineral Density: A Mendelian Randomization Study.

Body mass index (BMI) is closely associated with bone mineral density (BMD) in both men and women. However, the relationship between BMI and BMD varies according to different studies. Using SNPs strongly associated with BMI in 336,107 individuals, we conducted a two-sample Mendelian randomization study to identify whether and to what extent BMD at different skeletal sites was affected by BMI. A power calculation was also performed. We found that BMI may causally increase lumbar BMD (ß 0.087; 95% CI 0.025 to 0.149; P = 0.006) and heel calcaneus BMD (ß 0.120; 95% CI 0.082 to 0.157; P = 1 × 10-7). The associations of BMI with forearm and femoral neck BMD were not statistically significant. Our study suggested that higher BMI plays a causal role in increasing BMD and the effects are similar across the skeleton. BMI was causally and positively associated with lumbar and heel calcaneus BMD. However, no statistically significant effects were observed for BMI on femoral neck or forearm BMD.

Association of short-term exposure to sulfur dioxide and hospitalization for ischemic and hemorrhagic stroke in Guangzhou, China.

BACKGROUND: In developing countries, ambient sulfur dioxide (SO2) is a serious air pollutant concern, but there is no enough and consistent epidemiological evidence about its health effects on stroke hospitalization. METHODS: We collected the daily air pollution data, meteorological data and number of daily hospital admissions for ischemic and hemorrhagic stroke, in Guangzhou from January 1st 2009 to December 31st 2014. Then we applied generalized additive model with a quasi-Poisson link to assess the relationship between short-term SO2 exposure and the total number of hospital admissions for ischemic and hemorrhagic stroke. In addition, we evaluated the effect of ambient SO2 by age (< 65 years and ≥ 65 years). RESULTS: During the study period, a 24-h mean concentration of ambient SO2 of 27.82 µg/m3, a total of 58,473 ischemic stroke and 9167 hemorrhagic stroke hospital admissions hospital were recorded. Ambient SO2 was found to increase the risk for both ischemic and hemorrhagic stroke hospital admission in single pollutant model. The maximum value of percentage changes for ischemic and hemorrhagic stroke occurred in lag 0 day and lag 1 day, per 10 µg/m3 increase in SO2 concentrations was corresponded to a 1.27% (95% confidence interval (CI), 0.42-2.12%) and 1.55% (95%CI, 0.02-3.11%) increased risk, respectively. The association between SO2 and ischemic stroke hospitalization was robust to two pollutant model, but for hemorrhagic stroke it's partially weakened after adjusting for co-pollutants. The effect of ambient SO2 on ischemic stroke appeared to be greater for people < 65 years old, but null effect on hemorrhagic stroke was identified for both age groups. CONCLUSIONS: We found short-term exposure to ambient SO2 may significantly increase the risks of hospitalization for ischemic stroke. The findings may contribute to a better understanding of the health effects of low-levels of SO2.

Antinociceptive Efficacy of Retigabine and Flupirtine for Gout Arthritis Pain.

INTRODUCTION: Gout arthritis is an inflammatory disease characterized by severe acute pain. The goal of pharmacological gout arthritis treatments is to reduce pain, and thereby increase the patient's quality of life. The Kv7/M channel activators retigabine and flupirtine show analgesic efficacy in animal models of osteoarthritic pain. We hypothesized that these drugs may also alleviate gout arthritis pain. OBJECTIVE: To determine the effects of retigabine and flupirtine on pain behavior associated with monosodium urate (MSU)-induced gout arthritis. METHODS: The gout arthritis model was established with an intra-articular injection of MSU into the right ankle joint, animals were treated with retigabine or flupirtine, and pain-related behaviors were assessed. RESULTS: Retigabine and flupirtine significantly increased the mechanical threshold and prolonged the paw withdrawal latency in a rat model of gout arthritis pain in a dose-dependent manner. The antinociceptive effects of retigabine and flupirtine were fully antagonized by the Kv7/M channel blocker XE991. CONCLUSION: Retigabine and flupirtine showed antinociceptive effects for MSU-induced gout pain at different times during pain development.

Effects of delayed hip replacement on postoperative hip function and quality of life in elderly patients with femoral neck fracture.

BACKGROUND: For various reasons, some elderly patients with femoral neck fracture undergo delayed surgical treatment. There is little information about the effect of delayed treatment on postoperative hip function and quality of life. The aim of this study was to investigate the effect of delayed hip arthroplasty on hip function, quality of life, and satisfaction in patients with femoral neck fractures. METHODS: Forty-seven patients with femoral neck fracture and hip replacement delayed over 21 days served as the delayed group (D group). Patients with femoral neck fracture, matched 1:1 for age and sex, and hip replacement within 7 days served as the control group (C group). The Harris hip score (HHS) and health-related quality of life (HRQoL) were assessed before surgery and 3 months, 6 months and 1 year postoperatively. The satisfaction questionnaires were completed by the patients themselves at the last follow-up. RESULTS: The HHS in the C group was lower than that in the D group (32.64 ± 9.11 vs. 46.32 ± 9.88, P < 0.05) before surgery but recovered faster after surgery. The HHS in the D group was lower than that in the C group 1 year postoperatively (85.2 ± 3.80 vs. 89.8 ± 3.33, P < 0.05). The patients' quality of life changed similarly to their HHS. The HHS 1 year after surgery was related to the preoperative HHS in group D (rs = 0.521, P < 0.01). Patients in the D group showed significantly higher satisfaction scores than those in the C group (P < 0.05). CONCLUSIONS: Hip function in patients with femoral neck fracture surgery delayed over 21 days recovered more slowly than that in those who underwent surgery within 7 days. However, they were more satisfied with the surgery. Moderate hip movement to ameliorate the lower limb muscle atrophy was recommended for patients facing a temporary inability to undergo surgery.

Evaluation of a logistic regression model for predicting liver necroinflammation in hepatitis B e antigen-negative chronic hepatitis B patients with normal and minimally increased alanine aminotransferase levels.

Liver necroinflammation is the indicator for treating patients with chronic hepatitis B (CHB) infection. However, there is no suitable non-invasive index for diagnosing liver necroinflammation. This study aimed to create a non-invasive index to predict liver necroinflammation in patients who lack clear-cut clinical inflammation parameters. Patients who were hepatitis B e antigen (HBeAg)-negative and underwent liver histological diagnosis, had a normal or minimally increased alanine aminotransferase (ALT) level were enrolled. Liver necroinflammation was defined as histological active index ≥4. A logistic regression model (LRM) was established based on the parameters independently associated with liver necroinflammation. Of all 550 patients, 36.73% had necroinflammation. In patients with an abnormal ALT level, the rate of necroinflammation was 52.49%. The area under the curve (AUC) of the ALT level for predicting necroinflammation was 0.655 (95% confidence interval [CI], 0.609-0.702), and that of the HBV DNA level ≥2000 IU/mL combined with an abnormal ALT level was 0.618. By using the LRM, the AUC improved to 0.769 (95% CI, 0.723-0.815) with a Youden index of 0.519 and diagnostic accuracy of 75.3%. The cutoff value ≥0.7 in the LRM had a specificity of 97.4% and positive predictive value of 85.0% for predicting necroinflammation. By using the cutoff value <0.15 in the LRM, the presence of necroinflammation could be excluded with a negative predictive value of 90.8%. This study indicated that the LRM can be used to effectively diagnose liver necroinflammation in HBeAg-negative patients with CHB who have normal or minimally elevated ALT levels.

MiR-155 Enhances Insulin Sensitivity by Coordinated Regulation of Multiple Genes in Mice.

miR-155 plays critical roles in numerous physiological and pathological processes, however, its function in the regulation of blood glucose homeostasis and insulin sensitivity and underlying mechanisms remain unknown. Here, we reveal that miR-155 levels are downregulated in serum from type 2 diabetes (T2D) patients, suggesting that miR-155 might be involved in blood glucose control and diabetes. Gain-of-function and loss-of-function studies in mice demonstrate that miR-155 has no effects on the pancreatic ß-cell proliferation and function. Global transgenic overexpression of miR-155 in mice leads to hypoglycaemia, improved glucose tolerance and insulin sensitivity. Conversely, miR-155 deficiency in mice causes hyperglycemia, impaired glucose tolerance and insulin resistance. In addition, consistent with a positive regulatory role of miR-155 in glucose metabolism, miR-155 positively modulates glucose uptake in all cell types examined, while mice overexpressing miR-155 transgene show enhanced glycolysis, and insulin-stimulated AKT and IRS-1 phosphorylation in liver, adipose tissue or skeletal muscle. Furthermore, we reveal these aforementioned phenomena occur, at least partially, through miR-155-mediated repression of important negative regulators (i.e. C/EBPß, HDAC4 and SOCS1) of insulin signaling. Taken together, these findings demonstrate, for the first time, that miR-155 is a positive regulator of insulin sensitivity with potential applications for diabetes treatment.

Role of inflammation in the process of clinical Kashin-Beck disease: latest findings and interpretations.

Kashin-Beck disease (KBD), a particular type of osteoarthritis (OA), and an endemic disease with articular cartilage damage and chondrocytes apoptosis, can affect many joints, and the most commonly affected joints are the knee, ankle, and hand. KBD has traditionally been classified as a non-inflammatory OA. However, recent studies have shown that inflammation has played an important role in the development of KBD. Nowadays, clinical KBD is not only an endemic disease, but also a combined result of many other non-endemic factors, which contains age, altered biomechanics, joint trauma and secondary OA. The characteristics of the developmental joint failure of advanced KBD, because of the biochemical and mechanical processes, are tightly linked with the interaction of joint damage and its immune response, as well as the subsequent state of chronic inflammation leading to KBD progression. In this review, we focus on the epidemiology, pathology, imaging, cytokines and transduction pathways investigating the association of inflammation with KBD; meanwhile, a wide range of data will be discussed to elicit our current hypotheses considering the role of inflammation and immune activation in KBD development.

Comparative study of serum proteomes in Legg-Calve-Perthes disease.

BACKGROUND: Legg-Calve-Perthes Disease (LCPD) is an idiopathic osteonecrosis of the developing femoral head complicated by pain and disability of the hip joint. To date, the pathological mechanisms of LCPD are not well-known. This study screened the changes in serum protein expression in patients with LCPD. METHODS: Age- and sex-matched serum samples from 10 control subjects and 10 patients with LCPD were compared using the isobaric tags for relative and absolute quantification (iTRAQ) technique. Gene ontology analyses, KEGG pathway and functional network analyses were performed. Proteins of interest with large differences in expression, S100-A8, alpha-1-acid glycoprotein 1, haptoglobin and apolipoprotein E, were compared by western blotting. RESULTS: The disease/control ratios showed 26 proteins were significantly differentially expressed (all p < 0.05). Including higher abundances of complement factor H (1.44), complement C4-B (1.45), isocitrate dehydrogenase [NAD] subunit alpha (2.7) alpha-1-acid glycoprotein 1 (1.87), heptoglobin (1.53) and Ig lambda-2 chain C regions (1.46), and lower levels of apolipoprotein E (0.50), apolipoprotein F (0.60), apolipoprotein C-III (0.69), S100-A8 (0.73), S100-A9 (0.75) and prothrombin (0.77) in LCPD than in controls. The alpha-1-acid glycoprotein 1 and haptoglobin increases, and apolipoprotein E and S100-A8 decreases were confirmed by western blot. KEGG pathway analysis revealed these proteins were related to the complement and coagulation cascades, Staphylococcus aureus infection, PPAR signaling, fat digestion and absorption, and vitamin digestion and absorption. Functional network analysis suggested that the proteins were involved in lipid regulation. CONCLUSIONS: The complement and coagulation cascades, and abnormal lipid metabolism may be involved in the pathogenesis of LCPD.

Sciatic nerve course in adult patients with unilateral developmental dysplasia of the hip: implications for hip surgery.

BACKGROUND: Sciatic nerve injury is a disastrous adverse complication of surgery and can cause debilitating pain, functional impairment and poor quality of life. Patients with developmental dysplasia of the hip (DDH) have a high incidence of sciatic nerve injury after total hip arthroplasty (THA). A better understanding of the course of the sciatic nerve in patients with DDH may help minimise the risk of sciatic nerve injury after THA. METHODS: A total of 35 adult patients with unilateral DDH were enrolled in this retrospective study. We reviewed the patients' computed tomography (CT) scans, which included the area from the iliac crest to below the lesser trochanter. The distance between the sciatic nerve and regional anatomic landmarks in four different sections on CT scans was measured to identify the course of the sciatic nerve. RESULTS: The distance from the sciatic nerve to the spine's midline was shorter on the affected side than on the healthy side (p < 0.05); the same difference was also detected in the distance to the ilium/ischium outside the true pelvis (p < 0.05). The distance to the greater trochanter was longer on the affected side (p < 0.05). However, the two sides showed no significant difference in the distance from the sciatic nerve to the lesser trochanter (p > 0.05). CONCLUSIONS: For patients with unilateral DDH, the sciatic nerve was located near the ischium and ilium but relatively far from the femur of the affected hip joint, compared to its location on the healthy side. These findings reveal that sciatic nerve becomes shorter in the affected low-limb and is relatively unlikely to be directly injuried using the posterolateral approach in patients with unilateral DDH.

Ulnar Rotation Osteotomy for Congenital Radial Head Dislocation.

PURPOSE: To evaluate an ulnar rotation osteotomy for congenital anterior dislocation of the radial head. METHODS: Nine patients (5 boys and 4 girls aged 6 to 13 years) with congenital anterior dislocation of the radial head were treated with ulnar rotation osteotomy. Magnetic resonance imaging of the elbow showed the proximal radioulnar joint on the anterior-lateral side of the ulna rather than on the lateral side in patients with congenital anterior dislocation of the radial head. On the basis of this finding, we performed an osteotomy on the ulna and laterally rotated the proximal radioulnar joint achieving radial head reduction and restoring the anatomical relationship between the radial head and the capitellum. Clinical and radiographical evaluation of the elbow was performed before surgery and at postoperative follow-up. RESULTS: All patients were followed for 13 to 45 months after surgery. Elbow radiography showed that the radiocapitellar joint was reduced in all patients at the last follow-up visit and that the carrying angle was decreased relative to that in the preoperative condition. Elbow stability and the range of elbow flexion motion were improved at the last follow-up. We did not observe ulnar osteotomy site nonunion or elbow osteoarthritis in these patients. Furthermore, radial head dislocation did not recur. CONCLUSIONS: At early follow-up, ulnar rotation osteotomy was a safe and effective method for the treatment of congenital anterior dislocation of the radial head. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Beneficial effect of grape seed proanthocyanidin extract in rabbits with steroid-induced osteonecrosis via protecting against oxidative stress and apoptosis.

BACKGROUND: Oxidative damage and apoptosis play dominant roles in the pathogenesis of steroid-induced osteonecrosis (ON). Grape seed proanthocyanidin extract (GSPE) demonstrates antioxidant and antiapoptotic properties. Our aim was to demonstrate the effects of GSPE in preventing steroid-induced ON in rabbits. METHODS: Osteonecrosis was induced by high-dose methylprednisolone (40 mg/kg). Rabbits in the preventive medicine group were treated with 100 mg/kg/day GSPE for 14 consecutive days, and the presence or absence of ON was examined histopathologically. Oxidative damage in bone tissue was assessed by immunohistochemical staining of 8-oxo-2'-deoxyguanosine (8-OHdG), malondialdehyde (MDA) levels, and activities of antioxidant enzymes Cu/Zn superoxide dismutase (SOD) and phospholipid hydroperoxide glutathione peroxidase (GSH-Px). Apoptosis was detected via quantitative terminal deoxynucleotidyl transferase (TdT) deoxyuridine triphosphate nick end labelling (TUNEL) staining and activated caspase 3 immunoblotting and activity. RESULTS: GSPE significantly attenuated the changes of immunohistochemical staining of 8-OHdG, MDA levels, and antioxidant enzymes activities, which were caused by methylprednisolone administration. Quantitative TUNEL and caspase 3 assay showed lower apoptosis with GSPE application. Simultaneously, GSPE reduced the incidence of steroid-induced ON in an established rabbit model to 17.6 %, compared with 87.5 % in the steroid-only group. CONCLUSION: These results reveal that GSPE treatment could inhibit oxidative damage and apoptosis to exert beneficial effects on reducing the incidence of steroid-induced ON in rabbit models.

Effect of preoperative limb-length discrepancy on abductor strength after total hip arthroplasty in patients with developmental dysplasia of the hip.

BACKGROUND: Limb-length discrepancy (LLD) arising from hip subluxation or dislocation and accompanied by insufficiency of hip abductor in patients with developmental dysplasia of the hip (DDH) can be corrected partially or completely with total hip arthroplasty (THA). However, information about post-THA changes in abductor strength related to preoperative LLD in patients with DDH is lacking. We aimed to explore the post-THA recovery course of abductor muscle strength and its related factors in patients with DDH. METHODS: A cohort of 45 patients with unilateral DDH was divided into two groups according to their Crowe classification: patients with class I or II DDH formed Group M, and patients in class III and IV DDH formed Group S. The following parameters were measured on standardized antero-posterior hip radiographs taken in the supine position pre- and post-THA: abductor muscle length, abductor lever arm, LLD, and femoral offset (FO). Abductor strength was evaluated quantitatively with the Isomed 2000 isokinetic test system (1 week before the operation and 1, 3, 6, and 12 months after the operation). The contralateral normal hip joint served as a within-patient control. The affected side:healthy side ratios of the parameters above were calculated. RESULTS: Abductor strength ratio evaluated at the five follow-up time points was larger in Group M than that in Group S (p < 0.001). The average abductor strength ratio reached 78.5, 85.4, and 89.2% at the 3, 6, and 12 months postoperative exams, respectively, in Group M, and reached 50.3, 63.2, and 72.9% in Group S. The abductor muscle length ratio, the abductor muscle level arm ratio, and the FO ratio were significantly increased postoperatively, relative to preoperative assessment, in the two groups. LLD was reduced significantly postoperatively, relative to preoperative values, in both groups. Both preoperative LLD (r = -0.791, p < 0.001) and the change in abductor muscle length ratio (r = -0.659, p < 0.001) correlated with abductor strength recovery. CONCLUSION: Patients showed the greatest improvement in abductor strength within the first 6 months after THA, especially during the first 3 months. Abductor strength was consistently greater in patients with mild dysplasia than in patients with severe dysplasia. The extent of preoperative LLD and the increase in abductor length were related with post-THA abductor strength recovery in patients with DDH.

Genetic predisposition of BMP7 polymorphisms to lumbar disk herniation in the Chinese Han population.

Bone morphogenetic protein 7 (BMP7) can induce skeletal formation, promote the differentiation of chondrocytes and osteoblasts, and ameliorate intervertebral disc degeneration. The study was designed to evaluate the relationship of BMP7 variants to LDH risk in the Chinese Han population. BMP7 variants were genotyped with the Agena MassARRAY system among 690 LDH patients and 690 healthy controls. The odds ratio (OR) and 95% confidence interval (CI) were calculated by logistic regression. Multi-factor dimension reduction (MDR) (version 3.0.2) software was used to evaluate the effect of BMP7 variant-variant interaction on the susceptibility to LDH. Here, the risk-reducing association between rs230189 and LDH occurrence was found (p = 0.005, OR = 0.79). Specially, rs230189 was associated with decreased LDH risk in females (p = 0.001, OR = 0.60), elder group (p = 0.025, OR = 0.76), subjects with BMI < 24 kg/m2 (p = 0.027, OR = 0.48), nonsmokers (p = 0.001, OR = 0.66), and nondrinkers (p = 0.011, OR = 0.72). Moreover, rs1321862 might be the risk factor for LDH susceptibility among the participants with BMI < 24 kg/m2 (p = 0.024, OR = 1.84). MDR results displayed that rs230189 was the greatest attribution factor on LDH risk in the single-locus model, with an information gain of 0.44%. The present study demonstrated that BMP7 rs230189 g.55771443A>C may play a protective role against LDH risk. Our findings may help to understand the potential mechanism of BMP7 in LDH susceptibility.

Bioinformatics proved the existence of potential hub genes activating autophagy to participate in cartilage degeneration in osteonecrosis of the femoral head.

The obvious degeneration of articular cartilage occurs in the late stage of osteonecrosis of the femoral head (ONFH), which aggravates the condition of ONFH. This study aimed to demonstrate aberrant activation of autophagy processes in ONFH chondrocytes through bioinformatics and to predict and identify relevant hub genes and pathways. Differentially expressed genes (DEGs) were identified using R software in the GSE74089 dataset from the GEO database. DEGs were crossed with the Human Autophagy Database (HADb) autophagy genes to screen out autophagy-related differential genes (AT-DEGs). GSEA, GSVA, GO, and KEGG pathway enrichment analyses of AT-DEGs were performed. The STRING database was used to analyze the protein-protein interaction (PPI) of the AT-DEGs network, and the MCODE and CytoHubba plugin in the Cytoscape software was used to analyze the key gene cluster module and screen the hub genes. The PPI network of hub genes was constructed using the GeneMANIA database, and functional enrichment and gene connectivity categories were analyzed. The expression levels of hub genes of related genes in the ONFH patients were verified in the dataset GSE123568, and the protein expression was verified by immunohistochemistry in tissues. The analysis of DEGs revealed abnormal autophagy in ONFH cartilage. AT-DEGs in ONFH have special enrichment in macroautophagy, autophagosome membrane, and phosphatidylinositol-3-phosphate binding. In the GSE123568 dataset, it was also found that ATG2B, ATG4B, and UVRAG were all significantly upregulated in ONFH patients. By immunohistochemistry, it was verified that ATG2B, ATG4B, and UVRAG were significantly overexpressed. These three genes regulate the occurrence and extension of autophagosomes through the PI3KC3C pathway. Finally, we determined that chondrocytes in ONFH undergo positive regulation of autophagy through the corresponding pathways involved in three genes: ATG2B, ATG4B, and UVRAG.