Acetabular Revision Arthroplasty Based on 3-Dimensional Reconstruction Technology Using Jumbo Cups.

Background: This study was aimed at evaluating the changes in cup coverage (CC) and hip center of rotation (HCOR) in acetabular defects of various severities treated with acetabular revision using jumbo cups. Methods: A total of 86 hips were included. The American Academy of Orthopedic Surgeons (AAOS) classification of these patients was as follows: 16 patients, AAOS I; 16 patients, AAOS II; and 16 patients, AAOS III. A three-dimensional (3D) implant simulation technique was used to visualize the placement of jumbo cups during revision arthroplasty. The acetabular anteversion, inclination, CC, and the HCOR were measured. Results: The inclination and anteversion of simulated acetabular cups in AAOS I-III groups were consistent with the normal acetabular anatomy. Compared with the controls, in AAOS I-III groups, the HCOR was significantly increased and CC was significantly decreased. The HCOR elevation was significantly higher in AAOS III patients than in AAOS I (p = 0.001) and AAOS II patients (p < 0.001). The use of the jumbo cup technology for acetabular revision would decrease the CC in AAOS I-III patients to 86.47, 84.78, and 74.51%, respectively. Conclusion: Our study demonstrated that in patients with acetabular defects, acetabular revision arthroplasty using jumbo cups will lead to decreased CC and HCOR upshift. Upon classifying these patients according to the AAOS classification, CC decreased with the severity of acetabular defects, and the elevation of the HCOR in AAOS III patients exceeded 10 mm and was significantly higher than in other patients.

[Research status of acetabular reconstruction in Crowe type â ¡ and â ¢ developmental dysplasia of the hip].

Developmental dysplasia of the hip (DDH) is a major cause of hip arthritis and ultimately total hip arthroplasty. Due to the dysplastic acetabulum, how to place the acetabular cup becomes a challenge in acetabular reconstruction for such patients. Especially in the acetabula classified as Crowe typeⅡand type Ⅲ, the dislocation of the femoral head causes bone defects above the true acetabulum, which will affect the stability of the acetabular cup when the acetabular reconstruction is performed at the true acetabulum. Many acetabular reconstruction methods such as bone grafting, the use of small acetabular cups, socket medialization technique, and high hip center technique are used to increase the host bone coverage of the cup. However, each method has its own shortcomings that can not be ignored so that there is no unified conclusion on the acetabular reconstruction methods for Crowe typeⅡand type Ⅲ hip dysplasia. This article summarized and evaluated various reconstruction methods in combination with the acetabular morphology of DDH, and put forward the research direction in the future.

The MRI-based 3D morphologic changes of knee meniscus under knee weight-bearing and early flexion conditions.

There are few studies investigate morphologic changes of knee meniscus in vivo mechanical loading and three-dimensions (3D) deformation and displacement of the whole meniscus between in vivo mechanical loading and unloading conditions are still unclear. To investigate the displacements and 3D morphological changes of the menisci under knee weight-bearing and early flexion conditions in healthy adults using a Magnetic Resonance Imaging (MRI)-compatible loading device (a 3.0 T MR imaging system) combined with a newly developed 3D comparison technique. Fifteen healthy volunteers were recruited in this cross-sectional observational study. Each subject underwent MRIs of their dominant right knee in eight different scanning conditions using a 3.0-T MRI scanner with a custom-made MRI-compatible loading device. The knee meniscus images were 3D reconstructed, and dimensional comparisons were made for each meniscal model with baseline (0°-unloaded model). The morphologic changes of the meniscal-anterior horn (AH), body (BD), and posterior horn (PH) regions were expressed as mean positive and negative deviations. The displacements were further investigated, and the meniscal extrusions of different subregions were measured. The morphologic changing patterns of human meniscus under loading and flexions were presented using 3D chromatic maps. The bilateral menisci were generally shifting laterally and posteriorly in most flexion angles and were changing medially and anteriorly under fully extended knee loading conditions. The mean deviations were more significant with loading at 0° of knee flexion, while the PH region in the lateral side changed further posteriorly with loading in 30° flexion. Most of the differences were not significant in other flexion angles between loading conditions. The extrusion of meniscus's medial body was greater in full extension compared to any other flexing angles. Mechanical loading can significantly deform the menisci in knee extension; however, this effect is limited during knee flexion. Current study can be used as a reference for the evaluations of the integrity in meniscal functions.

Bone defect map of the true acetabulum in hip dysplasia (Crowe type II and III) based on three-dimensional image reconstruction analysis.

The high hip center technique (HHC) is considered to be feasible for acetabular reconstruction in patients with DDH, but there is little in-depth study of its specific impact on Crowe type II and III DDH. The purpose of this study was to simultaneously analyze the effect of HHC on bone coverage of the cup (CC) in the acetabular reconstruction of type II and III DDH patients and to propose a map of acetabular bone defects from the perspective of the cup. Forty-nine hip CT data of 39 patients with DDH (Crowe type II and III) were collected to simulate acetabular reconstruction by cup models of different sizes (diameter 38mm-50 mm, 2 mm increment) with the HHC technique. The frequency distribution was plotted by overlapping the portions of the 44 mm cups that were not covered by the host bone. The mean CC of cups with sizes of 38 mm, 40 mm, 42 mm, 44 mm, 46 mm, 48 mm, and 50 mm at the true acetabula were 77.85%, 76.71%, 75.73%, 74.56%, 73.68%, 72.51%, and 71.75%, respectively, and the maximum CC increments were 21.24%, 21.58%, 20.86%, 20.04%, 18.62%, 17.18%, and 15.42% (P < 0.001), respectively, after the cups were elevated from the true acetabula. The bone defect map shows that 95% of type II and III DDH acetabula had posterosuperior bone defects, and approximately 60% were located outside the force line of the hip joint. Acetabular cups can meet a CC of more than 70% at the true acetabulum, and approximately 60% of Crowe type II and III DDH patients can obtain satisfactory CC at the true acetabulum by using a 44-mm cup without additional operations.

Electrochemical DNA synthesis and sequencing on a single electrode with scalability for integrated data storage.

DNA has been considered as a compelling candidate for digital data storage due to advantages such as high coding density, long retention time, and low energy consumption. Despite many works reported, the development of a DNA-based database of full integration, high efficiency, and practical applicability is still challenging. In this work, we report the synthesis and sequencing of DNA on a single electrode with scalability for an integrated DNA-based data storage system. The synthesis of DNA is based on phosphoramidite chemistry and electrochemical deprotection. The sequencing relies on charge redistribution originated from polymerase-catalyzed primer extension, leading to a measurable current spike. By regeneration of the electrode after sequencing, repeated sequencing can be achieved to improve the accuracy. A SlipChip device is developed to simplify the liquid introduction involved in DNA synthesis and sequencing. As the proof-of-concept experiment, text information is stored in the system and then accurately retrieved.

[Research progression in the pathogenesis of osteoarthritis].

Osteoarthritis(OA) is one of the most common joint diseases. As Chinese society enters the age of aging, the incidence of OA has been soar year by year, and research on its pathogenesis has been continuously valued by researchers. Studies have found that inflammatory cytokines, mainly interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α), were responsible for the construction of OA inflammatory networks. It was also found that the overexpression of proteases, mainly matrix metalloproteinases(MMPs) and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS), was the direct cause of OA cartilage deficiency. What's more, signaling pathways such as stromal cell derived factor-1 (SDF-1) and Wnt, chondrocytic senescence and the senescence-associated secretory phenotype (SASP), chondrocyte apoptosis and autophagy, and estrogen all play significant roles in OA pathogenesis. This paper extensively reviews the research literature relevant to the pathogenesis of OA in recent years, and systematically expounds the pathogenesis of OA from two aspects:molecular level and cell level. At the end of the paper, we discussed and predicted some potential directions in the future clinical diagnosis and treatment of OA.

Effects of the depth of the acetabular component during simulated acetabulum reaming in total hip arthroplasty.

We aimed to evaluate whether there are differences in the rotation center, cup coverage, and biomechanical effects between conventional and anatomical technique. Computed tomography scans of 26 normal hips were used to simulate implantation of acetabular component. The hip rotation center and acetabular component coverage rate were calculated. Moreover, a finite element model of the hip joint was generated to simulate and evaluate the acetabular cup insertion. Micromotion and the peak stress distribution were used to quantify the biomechanical properties. The medial and superior shifts of the rotation center were 5.2 ± 1.8 mm and 1.6 ± 0.7 mm for the conventional reaming technique and 1.1 ± 1.5 mm and 0.8 ± 0.5 mm for anatomical technique, respectively. The acetabular component coverage rates for conventional reaming technique and anatomical technique were 86.8 ± 4% and 70.0 ± 7%, respectively. The micromotion of the cup with conventional reaming technique was greater than that with anatomical technique. The peak stress concentration was highest in the superior portion with conventional reaming technique, whereas with anatomical technique, there was no stress concentration. Paradoxically although the acetabular component coverage rate is larger with conventional reaming technique, anatomical technique provides less micromotion and stress concentration for initial cup stability. Thus, anatomical technique may be more suitable for acetabulum reaming during primary total hip arthroplasty.

Comparison of two different on-shelf femoral stems for Crowe type IV developmental dysplasia of the hip.

OBJECTIVE: This study was performed to evaluate the proximal anatomical compatibility of stems for treatment of Crowe IV developmental dysplasia of the hip (DDH) using a previously developed three-dimensional comparison technique. METHODS: Patients with Crowe IV DDH who underwent computed tomography were retrospectively analyzed. The femoral medullary canals were three-dimensionally reconstructed, and models of cementless modular (S-ROM; DePuy Synthes) and conical (Wagner Cone; Zimmer Biomet) implants were used for virtual implantation. The negative point percentages (NPPs) were applied to verify fitting. The average distance (deviation) and the root mean square of the distance (RMSd) were used to quantify geometric compatibilities. RESULTS: Four (16.7%) and 12 (50.0%) femoral medullary canals could not be fitted properly with either the modular or conical implant. The NPPs in the distal comparison region were significantly greater in the conical than modular group. The deviation was significantly smaller in the modular than conical group. The RMSd was also significantly smaller in the modular than conical group. CONCLUSIONS: Compared with conical implants, modular implants might be more effectively used in patients with Crowe type IV DDH. However, some Crowe IV DDH femurs with severe deformity cannot be fitted with either of these two on-shelf implants.

Multivariable analysis of anatomic risk factors for anterior cruciate ligament injury in active individuals.

OBJECTIVE: The aim of the present study was to compare the morphometric differences between patients with or without anterior cruciate ligament (ACL) injury, and identify the anatomic risk factors associated with ACL injury in active individuals. METHODS: The knee joint magnetic resonance images (MRI) of 100 subjects were included in this study. Data from the ACL-injured group (50 patients) and matched controls (50 subjects) were obtained from the same hospital. These data were analyzed by univariable analysis or multivariable conditional logistic regression analysis to examine the effects of the following variables on the risk of suffering ACL injury for the first time: TT-TG distance, medial and lateral tibial slope, intercondylar notch width and depth, femur condylar width, lateral femoral condylar depth, notch width index (NWI), notch shape index (NSI), notch depth index (NDI), and cross-sectional area (CSA). RESULTS: In the univariable analysis, the ACL-injured group had a larger TT-TG distance, increased medial and lateral tibial slope, narrower intercondylar notch width, deeper lateral femoral condylar depth, lesser NWI and NSI, and CSA when compared with the control group (P < 0.05). However, there were no significant between-group differences in intercondylar notch depth (P = 0.174), femur condylar width (P = 0.797), and NDI (P = 0.436). The multivariable analysis revealed that TT-TG distance [odds ratio (OR) = 1.37, 95% CI = 1.04-1.81, P = 0.028], medial tibial slope (OR = 1.30, 95% CI = 1.02-1.66, P = 0.036) and NWI (OR = 0.46, 95% CI = 0.24-0.91, P = 0.025) had significant multivariable associations with the sole independent risk of ACL injury. CONCLUSION: Larger TT-TG distance, increased MTS, and lesser NWI are independent anatomic risk factors for active individuals with ACL injury. LEVEL OF EVIDENCE: Case-control study; Level of Evidence, III.

Cyclooxygenase-2 expression correlates with development, progression, metastasis, and prognosis of osteosarcoma: a meta-analysis and trial sequential analysis.

Cyclooxygenase-2 (COX-2), a key enzyme in arachidonic acid metabolism, is involved in several cancers, including osteosarcoma. The prognostic significance of COX-2 in osteosarcoma remains controversial. This study was to analyze the potential clinical and prognostic effects of COX-2 protein expression in patients with osteosarcoma. Eligible articles were searched via online databases. The combined odds ratios (ORs) or hazard ratios (HRs) with their 95% confidence intervals (95% CIs) were calculated using the random-effects model. Trial sequential analysis (TSA) was applied to analyze the required information size and determine the reliability of the evidence. Twenty-three studies on COX-2 expression were identified, which included a total of 1084 patients with malignant osteosarcoma and 247 patients with benign osteochondroma. COX-2 protein expression in osteosarcoma was higher than in benign osteochondroma (OR = 7.66, P < 0.001). COX-2 expression was not correlated with age, gender, tumor location, cancer histology, or necrosis (P > 0.1), but was significantly associated with tumor grade (high grade vs. low grade: OR = 4.81, P < 0.001), clinical stage (stage 3-4 vs. stage 1-2: OR = 4.89, P < 0.001), and metastasis (yes vs. no: OR = 3.53, P < 0.001). Based on TSA results, we suggest that additional studies are not required to examine osteosarcoma vs. benign osteochondroma, tumor grade, clinical stage, or metastasis. No heterogeneity was observed in these analyses. COX-2 expression is linked to poor prognosis in metastasis-free survival, overall survival, and relapse-free survival, as indicated by multivariate analysis. Therefore, the expression of COX-2 may correlate with the development, progression, metastasis, and poor prognosis of osteosarcoma.

[Radiological study on the cup abduction angle during total hip arthroplasty].

OBJECTIVE: To analyze the relationship among the parameters by measuring the relevant parameters of the anteroposterior X-ray of both hips in patients after total hip arthroplasty, to discuss the reliable anatomical markers and reference standards of acetabulum placement in total hip arthroplasty, and finally to accurately control the abduction angle of acetabulum. METHODS: From January 2016 to June 2017, 282 patients (235 hips) underwent total hip arthroplasty and 128 patients(157 hips) met the inclusion criteria. There were 91 males and 37 females, 82 cases of the left hip and 75 cases of the right hip; ranging in age from 22 to 78 years old, with a mean of 55.1 years old. The abduction angle(ß), ilium thickness (a), acetabular cup insertion depth (b), ischial thickness (c), acetabular cup insertion depth(d), acetabular abrasion and contusion depth(e) were measured on the postoperative AP X-ray of both hips, and the data were compared. RESULTS: There was a positive correlation between ß and b (r=0.424, P=0.000), a negative correlation between ß and d (r=-0.407, P=0.000), a positive correlation between ß and b/a (r=0.419, P=0.000), a negative correlation between ß and d/c (r=-0.472, P=0.000). There was a linear relationship between ß and b/a (t=5.753, P=0.000) and a linear relationship between ß and d/c (t=-6.671, P=0.000). CONCLUSIONS: The outreach angle is mainly controlled by the distance between the outer edge of the cup and the outer edge of the cup in the inferior portion(d) during the operation. The distance b from the outer edge of the cup can be used as a reference.

Long non-coding RNA ASBEL promotes osteosarcoma cell proliferation, migration, and invasion by regulating microRNA-21.

Osteosarcoma is the most common malignant bone tumor in children and adolescents with high rate of incidence, high frequency of recurrence, and high degree of metastasis. This study aimed to investigate the effects of long noncoding RNA antisense ncRNA in the abundant in neuroepithelium area (ANA)/B-cell translocation gene 3 (BTG3) locus (lncRNA ASBEL) on the pathogenesis of osteosarcoma. The expression levels of ASBEL in human osteoblast cells and human osteosarcoma cells were evaluated using qRT-PCR. Effects of ASBEL knockdown on cell viability, migration, and invasion were detected using trypan blue exclusion assay, cell migration, and cell invasion assay, respectively. The regulatory effects of ASBEL on microRNA-21 (miR-21) were analyzed using qRT-PCR. The roles of miR-21 and protein phosphatase 2A (PP2A), the possible downstream factor of miR-21, in osteosarcoma cell proliferation, migration, and invasion were also explored. The results showed that ASBEL was highly expressed in osteosarcoma cells. Knockdown of ASBEL inhibited osteosarcoma cell viability, migration, and invasion, as well as the expression level of miR-21. PP2A was a direct target of miR-21, which participated in the effects of ASBEL and miR-21 on the activation of phosphatidylinositol 3-kinase/protein kinase 3/glycogen synthase kinase-3ß (PI3K/AKT/GSK3ß) and mitogen-activated protein kinase/extracellular regulated protein kinase (MEK/ERK) signaling pathways as well as the enhancement of osteosarcoma cell proliferation, migration, and invasion. In conclusion, we verified that ASBEL-miR-21-PP2A pathway might play critical regulatory effects on the pathogenesis of osteosarcoma and could be as the potential therapeutic target and biomarker for osteosarcoma treatment.

Glenoid morphology and the safe zone for protecting the suprascapular nerve during baseplate fixation in reverse shoulder arthroplasty.

PURPOSE: The purpose of this study was to investigate glenoid morphology and define the safe zone for protecting the suprascapular nerve baseplate screw during baseplate fixation in reverse shoulder arthroplasty (RSA) in a Chinese population. METHODS: Shoulder computed tomography (CT) scans from 56 subjects were retrospectively reviewed. Three-dimensional (3D) reconstruction was performed using Mimics software, and corresponding bony references were used to evaluate glenoid morphology. To standardize evaluation, the coronal scapular plane was defined. Safe fixation distances and screw placements were investigated by constructing a simulated cutting plane of the baseplate during RSA. RESULTS: Mean glenoid height was 35.83 ± 2.95 mm, and width was 27.32 ± 2.78 mm, with significant sexual dimorphism (p < 0.01). According to the cutting plane morphology, the average baseplate radius was 13.84 ± 1.34 mm. The distances from the suprascapular notch and from two bony reference points at the base of the scapular spine to the cutting plane were 30.27 ± 2.77 mm, 18.39 ± 1.67 mm and 16.52 ± 1.52 mm, respectively, with a gender-related difference. Based on the clock face indication system, the danger zone caused by the suprascapular nerve projection was oriented between the two o'clock and eight o'clock positions in reference to the right shoulder. CONCLUSIONS: Glenoid size and the safe zone for screw fixation during RSA were characterized in a Chinese population. Careful consideration of baseplate fixation and avoidance of suprascapular nerve injury are important for improved clinical outcome.

Preoperative T1 Slope as a Predictor of Change in Cervical Alignment and Range of Motion After Cervical Disc Arthroplasty.

BACKGROUND This study analyzed the effect of preoperative T1 slope on cervical alignment and range of motion (ROM) after cervical disc arthroplasty (CDA) in patients with cervical degenerative disease. MATERIAL AND METHODS This retrospective study included 32 patients with single-level symptomatic cervical disc disease who underwent CDA with the Mobi-C cervical disc prosthesis and had a mean follow-up of 26.8±6.4 months. Standing lateral, flexion, and extension X-rays of the cervical spine were obtained preoperatively and postoperatively at 24-month follow-up. Simple linear regression analysis was used to assess the impact of preoperative T1 slope on changes from preoperative values in radiologic parameters. RESULTS Compared to preoperative values, at 24-month follow-up, there was a significant increase in mean functional spinal unit (FSU) angle (+7.4°), upper adjacent segment (UAS) angle (+3.1°), and overall cervical alignment (C2-C7 angle) (+6.3°), and a significant decrease in mean lower adjacent segment (LAS) angle (-2.4°). Mean ROM of the FSU (-3.6°), LAS (-3.0°), and overall cervical spine (-11.5°) significantly decreased, and mean ROM of the UAS (+1.6°) significantly increased. There were significant correlations between preoperative T1 slope and mean change from preoperative value in FSU angle, C2-C7 angle, and ROM of the overall cervical spine (C2-C7). CONCLUSIONS T1 slope is useful for evaluating changes in the FSU angle, C2-C7 angle, and ROM of the overall cervical spine following CDA with the Mobi-C disc. Patients with a large preoperative T1 slope may be good candidates for CDA with the Mobi-C prosthesis due its motion maintenance and the fact that it has little adverse impact on sagittal alignment. It also could be a good option in terms of sagittal alignment improvement or motion maintenance for patients with kyphosis.

Morphological Analysis of True Acetabulum in Hip Dysplasia (Crowe Classes I-IV) Via 3-D Implantation Simulation.

BACKGROUND: The purpose of this study was to investigate the 3-dimensional (3D) morphological features of the true acetabulum in patients with developmental dysplasia of the hip (DDH). METHODS: Seventy-nine hips-53 in patients with developmental dysplasia of the hip (DDH) and 36 normal hips-were included in the present study. According to the Crowe classification, 26 hips were graded as Class I, 31 were Class II or III, and 22 were Class IV. The anterior pelvic plane was defined to standardize the measurements in the study. A selected virtual cup component was implanted into the true acetabulum of a 3D pelvic model of each hip. The acetabular anteversion angle, effective center-edge (CE) angle, effective Sharp angle, and thickness of the medial wall were measured to provide morphological indices of the true acetabulum. Acetabular sector angles and the component coverage ratio were measured to provide coverage indices. RESULTS: The acetabular anteversion angle increased with the severity of the DDH. Crowe-II/III hips had the smallest effective CE angle and the largest effective Sharp angle. The mean medial wall thickness was greatest in the Crowe-II/III hips (8.72 mm; 95% confidence interval [CI] = 7.52 to 9.92 mm), intermediate in the Crowe-I hips (7.17 mm; 95% CI = 6.24 to 8.11 mm), and smallest in the Crowe-IV hips (6.05 mm; 95% CI = 4.78 to 7.32 mm). The integrated coverage ratio of the Crowe-II/III hips was significantly less than that of the Crowe-I and IV hips. CONCLUSIONS: The morphological features of the true acetabulum in patients with DDH can be evaluated comprehensively by using 3D implantation simulation. Segmental bone deficiency was prevalent in the dysplastic hips, especially those in the Crowe-II/III group. Both the severity and the individual morphology of the acetabular dysplasia should be carefully considered in preoperative planning.

Correcting pelvic obliquity in the lateral position to improve acetabular component orientation during total hip arthroplasty.

BACKGROUND: The acetabular component orientation during total hip arthroplasty (THA) impacts future hip function and early revision. Correcting pelvic obliquity may improve outcomes. OBJECTIVE: To correct pelvic obliquity in the lateral position by applying a gradienter and plumb during THA using fluoroscopy. METHODS: Fifty patients undergoing THA were randomized and divided into 2 groups. In controls, acetabular components were placed using traditional methods. In experimental patients, acetabular components were placed after correcting pelvic obliquity. We measured pelvic obliquity and recorded intra-operative and post-operative abduction angles, comparing abduction angle bias between post-operative measurements and intra-operation estimations. RESULTS: Before correction, the average pelvic obliquity was -1.647∘± 4.512∘ in experimental patients. The average abduction angle in experimental patients was 42.685∘± 3.355∘ postoperatively, differing by 1.962∘± 1.515∘ from intra-operative estimates, while in control patients, it was 44.534∘± 4.844∘ postoperatively, differing by 4.244∘± 3.042∘ from intra-operative estimates. The bias of the abduction angle was much greater in control than in experimental patients (P< 0.05). CONCLUSION: The pelvic obliquity in the lateral position affects surgeon judgment during THA. By correcting pelvic obliquity with a gradienter and plumb, the abduction angle bias can be reduced.

Expression of CD44 standard form and variant isoforms in human bone marrow stromal cells.

Human Bone Marrow Stromal Cells (hBMSCs) can migrate from bone marrow to injured tissues, where they may differentiate into different types of new cells for replacement of dysfunctional cells. CD44 plays an important role in stem cell movement. The expression distribution of CD44 standard form (CD44S) and CD44 variants (CD44V) is closely related to cell movement and tissue migration. The aim of this study was to evaluate the expressions of CD44S and CD44V in hBMSCs. The hBMSCs from four human subjects were cultured in vitro. Phenotypic properties were analyzed by flow cytometry, and adipocyte and osteoblast differentiations were evaluated at passage 4. The expressions of CD44S and CD44V were examined using quantitative real-time polymerase chain reaction (q-PCR). Results showed that hBMSCs were successfully cultured, with positive expressions of markers of mesenchymal cells (CD90, CD73, CD105), and negative expressions of markers of hematopoietic cells (CD34, CD45). The cultured hBMSCs can be induced to differentiate into adipocytes and osteoblasts. Q-PCR results showed that the expression of CD44S was significantly higher than the expressions of different CD44V isoforms in different samples. These results revealed significant differences in the distributions of CD44S and CD44V gene expressions, demonstrating a dominant CD44S expression in hBMCSs.

Chitosan nanoparticle-delivered siRNA reduces CXCR4 expression and sensitizes breast cancer cells to cisplatin.

Chemokine (C-X-C motif) receptor 4 (CXCR4) has been reported as a poor prognostic biomarker in human breast cancers, and has been suggested as a promising therapeutic target of breast cancer treatment. The present study aims to investigate the delivery efficiency of siRNA by chitosan into breast cancer cells, and then to examine the regulatory role by chitosan nanoparticle-delivered siRNA on CXCR4 expression and on the chemosensitivity of breast cancer cells. Our results demonstrated that the siRNA could be capsuled by chitosan into nanoparticles with a diameter of 80-110 nm, and with a zeta potential of 20-50 mV. The chitosan nanoparticle delivered siRNA efficiently into breast cancer MCF-7 cells significantly reduced the expression of CXCR4 in both mRNA and protein levels. Moreover, the reduced CXCR4 by chitosan nanoparticle-delivered siRNA was associated with increased sensitivity of breast cancer cells to cisplatin. Reduced growth and increased apoptosis of MCF-7 cells were observed in the CXCR4 siRNA group than in the control siRNA group. Taken together, our results present the treatment potential of chitosan nanoparticle-delivered siRNA targeting CXCR4 in breast cancers.

Scavenger Receptor-Mediated Targeted Treatment of Collagen-Induced Arthritis by Dextran Sulfate-Methotrexate Prodrug.

Rheumatoid arthritis (RA) is a chronic autoimmune disorder implicated in multiple joint affection and even disability. The activated macrophages perform a predominant role in onset and persistence of RA. Scavenger receptor (SR), one of several receptors overexpressed on the activated macrophages, is a specific biomarker for targeted therapy of numerous chronic inflammation diseases like RA. In this work, dextran sulfate-graft-methotrexate conjugate (DS-g-MTX) is synthesized and characterized, which exhibits excellent targetability to SR on the activated RAW 264.7 cells. Additionally, the enhanced accumulation and potent inflammatory inhibition are observed in the affected joint after intravenous injection of DS-g-MTX, compared to the treatment with dextran-graft-methotrexate (Dex-g-MTX), as is confirmed by the detection of histopathology and pro-inflammatory cytokines. Our work highlights DS-g-MTX as a potential therapeutic option for RA aiming the SR-expressed activated macrophages.

Study of three-dimensional morphology of the proximal femur in developmental adult dysplasia of the hip suggests that the on-shelf modular prosthesis may not be an ideal choice for patients with Crowe type IV hips.

PURPOSE: The purpose of this study was to investigate the three-dimensional morphological features of the proximal femur of developmental dysplasia of the hip (DDH). METHODS: From January 2012 to December 2014, 38 patients (47 hips) of DDH were admitted and 30 normal hips were selected as controls. All hips from both groups were examined by CT scan. CT data were imported into Mimics 17.0. Three-dimensional models of the proximal femur were then reconstructed, and the following parameters were measured: neck-shaft angle, neck length, offset, height of the centre of femoral head, level of isthmus, height of the tip of greater trochanter, the medullary canal diameter of isthmus(Di), the medullary canal diameter 10 mm above the apex of the lesser trochanter(DT + 10), the medullary canal diameter 20 mm below the apex of the lesser trochanter(DT-20), and then DT + 10/Di, DT-20/Di and DT + 10/DT-20 were calculated. RESULTS: There was no significant difference in neck-shaft angle between Crowe I, Crowe II-III DDH and the control group, while the neck-shaft angle was much smaller in Crowe IV DDH. The neck length of Crowe IV DDH was also much smaller than those of Crowe I and Crowe II-III DDH. Height of the tip greater trochanter in Crowe IV was greater than that in Crowe I, Crowe II-III DDH and the control group. The centre of femoral head in Crowe IV DDH was lower than those in Crowe I, Crowe II-III DDH and the control group. The level of isthmus in Crowe IV was much higher than those in Crowe I, Crowe II-III DDH and the control group. DT + 10, DT-20, DT + 10/Di and DT-20/Di were much smaller in Crowe IV DDH than those in Crowe I, Crowe II-III and the control group. CONCLUSIONS: Neck-shaft angle in the DDH groups was not larger than that in the control group. Comparing to Crowe I, Crowe II-III DDH and the control group, Crowe IV DDH had a dramatic change in the intramedullary and extramedullary parameters, especially the dramatic narrowing of medullary canal around the level of the lesser trochanter. The on-shelf modular prosthesis may not be an ideal choice for the Chinese patients with Crowe IV hips.