Application of functional magnetic resonance imaging for evaluation of cartilage injury effect on knee joint function by recurrent patellar dislocation.

Explore the therapeutic effect of vastus medialis oblique plasty and the reliability and applicability of functional magnetic resonance imaging as a diagnostic method for early cartilage degeneration and injury diagnosis. From July 2020 to July 2022, there were 53 patients with recurrent patellar dislocation who met the inclusion criteria for surgery, including 34 women and 19 men, aged 11 to 53 years, with an average age of 24.4 years. After patient selection, functional magnetic resonance imaging was performed before surgery. According to the presence or absence of cartilage injury, they were divided into cartilage injury group (n = 28) and non-cartilage injury group (n = 25), and underwent vastus medialis oblique plasty. Preoperative patellar axial radiographs were performed in both groups of patients to measure the patellar tilt angle and lateral patellofemoral angle. The Lysholm, Kujala, and VAS (visual analogue scale) scores were applied to assess changes in knee joint function and anterior knee pain. All patients were postoperatively followed up. The patellar tilt angle and lateral patellofemoral angle of the 2 groups were significantly improved postoperatively (P < .05), with no statistical difference between the 2 groups (P > .05). Significant differences were observed in the VAS changes between the cartilage injury group and the non-cartilage injury group before and after operation (P < .05). There was a statistical difference in VAS score between the groups (P < .05). The changes in the Lysholm and Kujala scores before and after the operation in the cartilage injury and the non-cartilage injury groups were statistically different (P < .05). There was statistical difference between the 2 groups in Lysholm score and Kujala score after operation (P < .05). Vastus medialis oblique plasty significantly improved knee joint function and pain. Patients with cartilage injury had worse preoperative and postoperative knee function than patients without cartilage injury. Functional magnetic resonance imaging can reflect the early-stage changes in the biochemical cartilage components caused by recurrent patellar dislocation.

Evaluation of an Autologous Bone Mesenchymal Stem Cell-Derived Extracellular Matrix Scaffold in a Rabbit and Minipig Model of Cartilage Repair.

BACKGROUND This study aimed to evaluate an autologous bone mesenchymal stem cell (MSC)-derived extracellular matrix (ECM) scaffold in two animal models of cartilage repair. MATERIAL AND METHODS A rabbit model (n=16) and a minipig model (n=8) of cartilage repair were created with cartilage defects of the knee joints treated with bone marrow stimulation (BMS). In the ECM group, autologous bone MSC-derived ECM scaffolds were implanted into the cartilage defects after bone marrow stimulation. In the BMS group, the cartilage defects were treated by bone marrow stimulation only. The renewal capacity of bone MSCs was measured with a colony-forming unit fibroblast (CFU-F) in vitro assay. The extent of cartilage repair was as-sessed at 6 months after surgery. RESULTS In the rabbit model, the macroscopic appearance of the exudate of the healing wounds in the ECM group showed less fibrosis, and the histology showed more evenly distributed chondrocytes compared with the BMS group. The CFU-F assay showed that the number of bone MSCs in the ECM group was approximately was twice that of the BMS group. In the minipig model, the macroscopic appearance and magnetic resonance imaging (MRI) findings of the ECM group were improved when compared with the BMS group. The repaired tissue in ECM group had similar histological characteristics and biochemical content to normal hyaline cartilage. CONCLUSIONS In two animal models of knee joint cartilage repair, the use of an ECM scaffold increased the number of bone MSCs and improved the extent of cartilage repair.

A four serum-miRNA panel serves as a potential diagnostic biomarker of osteosarcoma.

BACKGROUND: Osteosarcoma (OS) is the most common malignant bone tumor in young adults and adolescents with approximately 3 million new cases annually. Due to the lack of sensitive and specific diagnostic biomarkers, although OS patients are curable after surgical resection, many patients suffer from metastasis or recurrence. This study aimed to investigate whether circulating microRNAs (miRNAs) could serve as biomarkers for the diagnosis of OS. MATERIALS AND METHODS: Healthy individuals and OS patients enrolled in this study came from Nanjing First Hospital. First, candidate miRNAs were selected by integrated analysis of two GEO datasets and a publicly available miRNA dataset. The expression of these miRNAs in tissues and serum samples were subsequently examined through qRT-PCR. The diagnostic utility of these differential miRNAs was examined by using receiver operating characteristic (ROC) curve analysis. Finally, the potential signaling pathways associated with candidate miRNAs were searched through online tools. RESULTS: Four miRNAs (miR-487a, miR-493-5p, miR-501-3p and miR-502-5p) were selected to further investigate their diagnostic potential for OS. We discovered miR-487a, miR-493-5p, miR-501-3p and miR-502-5p were upregulated in OS tissues and serums. Besides, miR-487a, miR-493-5p, miR-501-3p and miR-502-5p in peripheral blood of OS patients were tumor-derived. The area under the ROC curve (AUC) was 0.83 (95% CI 0.71-0.97) for miR-487a, 0.79 (95% CI 0.66-0.93) for miR-493-5p, 0.82 (95% CI 0.68-0.95) for miR-501-3p, 0.83 (95% CI 0.72-0.95) for miR-502-5p, and 0.89 (95% CI 0.78-1.0) for miRNAs combination. CONCLUSION: Circulating miR-487a, miR-493-5p, miR-501-3p and miR-502-5p were novel potential diagnostic biomarkers of OS.

Identification of circulating miR-663a as a potential biomarker for diagnosing osteosarcoma.

PURPOSE: Osteosarcoma (OS) is the most common malignant bone tumor in children and young adults. The overall survival rate of OS patients has not been improved during the last 25 years, in part due to the lack of sensitive and specific biomarkers. This study aimed to investigate miRNAs existing in the peripheral blood as diagnostic biomarkers of OS. PATIENTS AND METHODS: OS patients and healthy controls (HCs) in this study were enrolled from Nanjing First Hospital. Candidate miRNA was selected by comprehensive analysis of GEO database. The expressions of candidate miRNA in tissues and plasma samples were subsequently examined through qRT-PCR. The diagnostic utility of candidate miRNA was examined by using receiver operating characteristic (ROC) curve analysis. RESULTS: After analysis of GEO database and clinical plasma samples, miR-663a was selected as a candidate miRNA to further investigate its value for diagnosing OS due to the highest differential fold change. We discovered that miR-663a expressions were remarkably elevated in both tissues and plasmas of OS patients. In addition, upregulated miR-663a in peripheral blood of OS patients was proved to be tumor-derived. The area under the ROC curve (AUC) was 0.86 (95%CI: 0.78 to 0.93) for miR-663a with 67.35% sensitivity and 89.8% specificity. CONCLUSION: Plasma miR-663a was identified as a novel potential biomarker for the diagnosis of OS.

Chondrogenic Differentiation Could Be Induced by Autologous Bone Marrow Mesenchymal Stem Cell-Derived Extracellular Matrix Scaffolds Without Exogenous Growth Factor.

We previously found that the combination of an autologous bone mesenchymal stem cell-derived extracellular matrix (aBMSC-dECM) scaffold with bone marrow stimulation could enhance hyaline cartilage regeneration. We suspected that chondrogenic differentiation could be induced by the aBMSC-dECM scaffold. This study aimed to investigate whether aBMSC-dECM scaffolds could promote chondrogenic differentiation without exogenous growth factors. BMSCs were seeded on aBMSC-dECM scaffolds and cultured in vitro with or without transforming growth factor-ß3 (E(+) or E(-) group). Atelocollagen scaffolds were used as controls (C(+) or C(-) group). The chondrogenic differentiation was evaluated by histological, biochemical, and real-time polymerase chain reaction assays. After 3 weeks, cartilage-like tissue with a homogeneous structure, a high cartilaginous matrix content (proteoglycan and type II collagen), and high expression levels of cartilage-associated genes (COL2A1, ACAN, and SOX9) were observed in the E(+), E(-), and C(+) groups. In addition, BMSCs in each scaffold (E group or C group) were preconditioned with chondrogenic media in vitro for 1 week, and then implanted in the backs of nude mice for 3 weeks. Three weeks later, cartilage matrix formation (proteoglycan and type II collagen) was achieved only in the E group, confirmed by safranin O staining and immunohistochemical staining for type II collagen. Taken together, these results indicate that aBMSC-dECM scaffolds could induce chondrogenic differentiation. Thus, they could be successful candidate scaffolds for cartilage tissue engineering.

[Current therapy status and research progress of cartilage defects of knees].

To demonstrate the current strategies for treating cartilage defects of knees and the related research. Published papers about cartilage defects were searched and reviewed. The current strategies for the treatment were summarized. Based on the research of our study and others, the conclusion how to treat cartilage defects was made. The current ways for treating cartilage defects include micro-fractures, chondrocytes transplantation, mosaicplasty and tissue engineering; Research on functional magnetic resonance imaging in the early diagnosis of cartilage defects, cartilage degeneration is gradually increasing. There is still no effective treatment of cartilage defects and tissue engineering has brought new hopes for the treatment of cartilage defects , functional magnetic resonance imaging has some significance in early diagnosis of cartilage defects, cartilage degeneration.

Technetium-99m-labeled annexin V imaging for detecting prosthetic joint infection in a rabbit model.

Accurate and timely diagnosis of prosthetic joint infection is essential to initiate early treatment and achieve a favorable outcome. In this study, we used a rabbit model to assess the feasibility of technetium-99m-labeled annexin V for detecting prosthetic joint infection. Right knee arthroplasty was performed on 24 New Zealand rabbits. After surgery, methicillin-susceptible Staphylococcus aureus was intra-articularly injected to create a model of prosthetic joint infection (the infected group, n = 12). Rabbits in the control group were injected with sterile saline (n = 12). Seven and 21 days after surgery, technetium-99m-labeled annexin V imaging was performed in 6 rabbits of each group. Images were acquired 1 and 4 hours after injection of technetium-99m-labeled annexin V (150 MBq). The operated-to-normal-knee activity ratios were calculated for quantitative analysis. Seven days after surgery, increased technetium-99m-labeled annexin V uptake was observed in all cases. However, at 21 days a notable decrease was found in the control group, but not in the infected group. The operated-to-normal-knee activity ratios of the infected group were 1.84 ± 0.29 in the early phase and 2.19 ± 0.34 in the delay phase, both of which were significantly higher than those of the control group (P = 0.03 and P = 0.02). The receiver operator characteristic curve analysis showed that the operated-to-normal-knee activity ratios of the delay phase at 21 days was the best indicator, with an accuracy of 80%. In conclusion, technetium-99m-labeled annexin V imaging could effectively distinguish an infected prosthetic joint from an uninfected prosthetic joint in a rabbit model.

Using 7.0T MRI T2 mapping to detect early changes of the cartilage matrix caused by immobilization in a rabbit model of immobilization-induced osteoarthritis.

OBJECTIVE: The goal of this study was to detect early changes in the cartilage matrix caused by immobilization in a rabbit model of immobilization-induced osteoarthritis (OA) by T2 mapping with 7.0T MRI. MATERIALS AND METHODS: Left knee joints of 28 mature rabbits were immobilized at 180° of extension with orthopedic casting tape for 1, 2, or 3weeks (n=7 rabbits each). No immobilization was performed in the control group (n=7 rabbits). T2 mapping was performed after 1, 2, and 3weeks. Osteochondral specimens harvested from the trochlea groove (TG) and medial femoral condyle (MFC) were subjected to histologic, immunohistochemical, and microscopic evaluation, followed by biochemical assays for water, glycosaminoglycan (GAG), and collagen. The ability of T2 mapping to reveal changes in the cartilage matrix was further assessed. RESULTS: Rabbits demonstrated elevated T2 values (9.9% in TG, 10.6% in MFC), a dulled cartilage surface, reduced Safranin-O staining, and decreased GAG content (14.2% in TG and MFC) after 2weeks, with cartilage surface softening, irregularity, and markedly reduced GAG content by 3weeks. T2 values were correlated positively with water (r=0.836 in TG, r=0.821 in MFC) and negatively with GAG content (r=-0.945 in TG, r=-0.957 in MFC), but had no discernible relationship with collagen content (r=-0.196 in TG, r=-0.213 in MFC). CONCLUSIONS: 7.0T MRI T2 mapping can be used to detect early changes of the cartilage matrix caused by immobilization in an immobilization-induced OA model.

Design, construction and mechanical testing of digital 3D anatomical data-based PCL-HA bone tissue engineering scaffold.

The study aims to investigate the techniques of design and construction of CT 3D reconstructional data-based polycaprolactone (PCL)-hydroxyapatite (HA) scaffold. Femoral and lumbar spinal specimens of eight male New Zealand white rabbits were performed CT and laser scanning data-based 3D printing scaffold processing using PCL-HA powder. Each group was performed eight scaffolds. The CAD-based 3D printed porous cylindrical stents were 16 piece × 3 groups, including the orthogonal scaffold, the Pozi-hole scaffold and the triangular hole scaffold. The gross forms, fiber scaffold diameters and porosities of the scaffolds were measured, and the mechanical testing was performed towards eight pieces of the three kinds of cylindrical scaffolds, respectively. The loading force, deformation, maximum-affordable pressure and deformation value were recorded. The pore-connection rate of each scaffold was 100 % within each group, there was no significant difference in the gross parameters and micro-structural parameters of each scaffold when compared with the design values (P > 0.05). There was no significant difference in the loading force, deformation and deformation value under the maximum-affordable pressure of the three different cylinder scaffolds when the load was above 320 N. The combination of CT and CAD reverse technology could accomplish the design and manufacturing of complex bone tissue engineering scaffolds, with no significant difference in the impacts of the microstructures towards the physical properties of different porous scaffolds under large load.

Chondrogenic regeneration using bone marrow clots and a porous polycaprolactone-hydroxyapatite scaffold by three-dimensional printing.

Scaffolds play an important role in directing three-dimensional (3D) cartilage regeneration. Our recent study reported the potential advantages of bone marrow clots (MC) in promoting extracellular matrix (ECM) scaffold chondrogenic regeneration. The aim of this study is to build a new scaffold for MC, with improved characteristics in mechanics, shaping, and biodegradability, compared to our previous study. To address this issue, this study prepared a 3D porous polycaprolactone (PCL)-hydroxyapatite (HA) scaffold combined with MC (Group A), while the control group (Group B) utilized a bone marrow stem cell seeded PCL-HA scaffold. The results of in vitro cultures and in vivo implantation demonstrated that although an initial obstruction of nutrient exchange caused by large amounts of fibrin and erythrocytes led to a decrease in the ratio of live cells in Group A, these scaffolds also showed significant improvements in cell adhesion, proliferation, and chondrogenic differentiation with porous recanalization in the later culture, compared to Group B. After 4 weeks of in vivo implantation, Group A scaffolds have a superior performance in DNA content, Sox9 and RunX2 expression, cartilage lacuna-like cell and ECM accumulation, when compared to Group B. Furthermore, Group A scaffold size and mechanics were stable during in vitro and in vivo experiments, unlike the scaffolds in our previous study. Our results suggest that the combination with MC proved to be a highly efficient, reliable, and simple new method that improves the biological performance of 3D PCL-HA scaffold. The MC-PCL-HA scaffold is a candidate for future cartilage regeneration studies.

Composite scaffolds composed of bone marrow mesenchymal stem cell-derived extracellular matrix and marrow clots promote marrow cell retention and proliferation.

Various biomaterials have been investigated in attempts to improve the mechanical stability of marrow clots derived from microfracture to obtain repaired tissue closely resembling hyaline cartilage. The goal of this study was to investigate the retention, adhesion, proliferation, and cartilage extracellular matrix (ECM) production of marrow clot-derived cells within a bone marrow mesenchymal stem cell-derived (BMSC-d) ECM/marrow clot composite scaffold. We fabricated BMSC-dECM/marrow clot composite scaffolds and kept them in chondrogenic medium in vitro for 1, 3, or 6 weeks. Unmodified marrow clots were used as a control. The BMSC-dECM/marrow clot composite scaffold exhibited a porous structure suitable for cell attachment and growth and further maintained cell viability. The DNA content measurements revealed that more cells proliferated in the BMSC-dECM/marrow clot composite scaffolds over time than in the marrow clots. Furthermore, the histologic, immunohistochemical, and western blot results demonstrated that the BMSC-dECM/marrow clot composite scaffold produced more hyaline-like cartilage and less fibrocartilage than the marrow clot in culture. Taken together, these findings indicate that the porous BMSC-dECM/marrow clot composite scaffold promotes the retention, attachment, and proliferation of cells from the marrow clot, and thus can stabilize the marrow clot to support chondrogenesis.

Preparation and characterization of bone marrow mesenchymal stem cell-derived extracellular matrix scaffolds.

The aim of this study was to assess the feasibility of creating extracellular matrix (ECM) scaffolds from mesenchymal stem cells. Bone marrow mesenchymal stem cell (BMSC)-derived ECM (BMSC-dECM) scaffolds were fabricated by lyophilization after crosslinking, without using a decellularization process. Acellular porcine chondrocyte-derived ECM (AC-dECM) scaffolds were used as a control. The surface morphology, internal structure, water uptake ratio, mechanical properties, and biocompatibility of the scaffolds, as well as the in vitro behavior of cells grown on the scaffolds were examined and compared between the two scaffold types. For the BMSC-dECM scaffolds, the average pore size was 304.4 ± 108.2 µm, average porosity was 93.3% ± 4.5%, average compressive modulus was 6.8 ± 1.5 kPa, and average water uptake ratio exceeded 20. The BMSC-dECM scaffolds supported the in vitro attachment and proliferation of cells, with these aspects likely being comparable to those of the AC-dECM scaffolds. The findings of this preliminary study highlight the potential utility of BMSC-derived ECM scaffolds for future cartilage tissue-engineering applications.

Chondrogenic differentiation of marrow clots after microfracture with BMSC-derived ECM scaffold in vitro.

Repairing articular cartilage by combining microfracture and various scaffolds has been extensively performed in in vivo animal models. We previously described a novel extracellular matrix (ECM) scaffold for cartilage tissue engineering. The aim of this study was to investigate the effect of a bone marrow-derived mesenchymal stem cells-derived ECM (BMSC-dECM) scaffold on the chondrogenic differentiation of marrow clots following microfracture in vitro. In this study, we manufactured the BMSC-dECM scaffold using a freeze-drying method. To obtain the marrow clots, a full-thickness cartilage defect was established and microholes were created in the trochlear groove of New Zealand white rabbits. The samples were divided and cultured in vitro for 1, 2, 4, and 8 weeks. The samples included a culture of the marrow clot alone (Group 1), a culture of the marrow clot with transforming growth factor-beta 3 (TGF-ß3) (Group 2), a culture of the composite of the BMSC-dECM scaffold and the marrow clot alone (Group 3), and a culture of the composite with TGF-ß3 (Group 4). A smooth and glossy surface was observed in Group 2 and Group 4 over time, but the surface for Group 4 was larger from week 1 onward. Compressive strength gradually increased in Groups 2 and 4, and greater increases were observed in Group 4 during the 8-week culture period. Enhanced cartilage-like matrix deposition of glycosaminoglycan (GAG) and type II collagen were confirmed by Safranin O and immunohistochemistry staining, respectively, in Groups 2 and 4. The GAG and collagen contents also gradually increased over time in Groups 2 and 4; the increase was greater in Group 4. In addition, real-time-polymerase chain reaction demonstrated that the expression of chondrogenic genes, such as COL2, ACAN, and SOX9, was gradually upregulated in Groups 2 and 4. However, greater increases in the expression of these cartilage-like genes were observed in Group 4 from week 4 onward. Our results suggest that the BMSC-dECM scaffold may favor the chondrogenesis of marrow clots following microfracture in vitro. In conclusion, these tissue engineering-like constructs could be potential candidates for cartilage repair.

An autologous bone marrow mesenchymal stem cell-derived extracellular matrix scaffold applied with bone marrow stimulation for cartilage repair.

PURPOSE: It is well known that implanting a bioactive scaffold into a cartilage defect site can enhance cartilage repair after bone marrow stimulation (BMS). However, most of the current scaffolds are derived from xenogenous tissue and/or artificial polymers. The implantation of these scaffolds adds risks of pathogen transmission, undesirable inflammation, and other immunological reactions, as well as ethical issues in clinical practice. The current study was undertaken to evaluate the effectiveness of implanting autologous bone marrow mesenchymal stem cell-derived extracellular matrix (aBMSC-dECM) scaffolds after BMS for cartilage repair. METHODS: Full osteochondral defects were performed on the trochlear groove of both knees in 24 rabbits. One group underwent BMS only in the right knee (the BMS group), and the other group was treated by implantation of the aBMSC-dECM scaffold after BMS in the left knee (the aBMSC-dECM scaffold group). RESULTS: Better repair of cartilage defects was observed in the aBMSC-dECM scaffold group than in the BMS group according to gross observation, histological assessments, immunohistochemistry, and chemical assay. The glycosaminoglycan and DNA content, the distribution of proteoglycan, and the distribution and arrangement of type II and I collagen fibers in the repaired tissue in the aBMSC-dECM scaffold group at 12 weeks after surgery were similar to that surrounding normal hyaline cartilage. CONCLUSIONS: Implanting aBMSC-dECM scaffolds can enhance the therapeutic effect of BMS on articular cartilage repair, and this combination treatment is a potential method for successful articular cartilage repair.

Feasibility of autologous bone marrow mesenchymal stem cell-derived extracellular matrix scaffold for cartilage tissue engineering.

Extracellular matrix (ECM) materials are widely used in cartilage tissue engineering. However, the current ECM materials are unsatisfactory for clinical practice as most of them are derived from allogenous or xenogenous tissue. This study was designed to develop a novel autologous ECM scaffold for cartilage tissue engineering. The autologous bone marrow mesenchymal stem cell-derived ECM (aBMSC-dECM) membrane was collected and fabricated into a three-dimensional porous scaffold via cross-linking and freeze-drying techniques. Articular chondrocytes were seeded into the aBMSC-dECM scaffold and atelocollagen scaffold, respectively. An in vitro culture and an in vivo implantation in nude mice model were performed to evaluate the influence on engineered cartilage. The current results showed that the aBMSC-dECM scaffold had a good microstructure and biocompatibility. After 4 weeks in vitro culture, the engineered cartilage in the aBMSC-dECM scaffold group formed thicker cartilage tissue with more homogeneous structure and higher expressions of cartilaginous gene and protein compared with the atelocollagen scaffold group. Furthermore, the engineered cartilage based on the aBMSC-dECM scaffold showed better cartilage formation in terms of volume and homogeneity, cartilage matrix content, and compressive modulus after 3 weeks in vivo implantation. These results indicated that the aBMSC-dECM scaffold could be a successful novel candidate scaffold for cartilage tissue engineering.

[Effect of bone marrow mesenchymal stem cells-derived extracellular matrix scaffold on chondrogenic differentiation of marrow clot after microfracture of bone marrow stimulation in vitro].

OBJECTIVE: To evaluate the feasibility and validity of chondrogenic differentiation of marrow clot after microfracture of bone marrow stimulation combined with bone marrow mesenchymal stem cells (BMSCs)-derived extracellular matrix (ECM) scaffold in vitro. METHODS: BMSCs were obtained and isolated from 20 New Zealand white rabbits (5-6 months old). The 3rd passage cells were cultured and induced to osteoblasts, chondrocytes, and adipocytes in vitro, respectively. ECM scaffold was manufactured using the 3rd passage cells via a freeze-dying method. Microstructure was observed by scanning electron microscope (SEM). A full-thickness cartilage defect (6 mm in diameter) was established and 5 microholes (1 mm in diameter and 3 mm in depth) were created with a syringe needle in the trochlear groove of the femur of rabbits to get the marrow clots. Another 20 rabbits which were not punctured were randomly divided into groups A (n=10) and B (n=10): culture of the marrow clot alone (group A) and culture of the marrow clot with transforming growth factor beta3 (TGF-beta3) (group B). Twenty rabbits which were punctured were randomly divided into groups C (n=10) and D (n=10): culture of the ECM scaffold and marrow clot composite (group C) and culture of the ECM scaffold and marrow clot composite with TGF-beta3 (group D). The cultured tissues were observed and evaluated by gross morphology, histology, immunohistochemistry, and biochemical composition at 1, 2, 4, and 8 weeks after culture. RESULTS: Cells were successfully induced into osteoblasts, chondrocytes, and adipocytes in vitro. Highly porous microstructure of the ECM scaffold was observed by SEM. The cultured tissue gradually reduced in size with time and disappeared at 8 weeks in group A. Soft and loose structure developed in group C during culturing. Chondroid tissue with smooth surface developed in groups B and D with time. The cultured tissue size of groups C and D were significantly larger than that of group B at 4 and 8 weeks (P < 0.05); group D was significantly larger than group C in size (P < 0.05). Few cells were seen, and no glycosaminoglycan (GAG) and collagen type II accumulated in groups A and C; many cartilage lacunas containing cells were observed and more GAG and collagen type II were synthesized in groups B and D. The contents of GAG and collagen increased gradually with time in groups B and D, especially in group D, and significant difference was found between groups B and D at 4 and 8 weeks (P < 0.05). CONCLUSION: The BMSCs-derived ECM scaffold combined with the marrow clot after microfracture of bone marrow stimulation is effective in TGF-beta3-induced chondrogenic differentiation in vitro.

[Preliminary clinical application of SL-PLUS MIA femoral stem prosthesis in total hip arthroplasty].

OBJECTIVE: To investigate the short-term effectiveness of total hip arthroplasty (THA) with SL-PLUS MIA femoral stem prosthesis by comparing with the SL-PLUS prosthesis. METHODS: Retrospective analysis was made on the clinical data of 33 patients (38 hips) undergoing THA with SL-PLUS MIA femoral stem prosthesis (trial group) between June and December 2011, which was compared with those of 35 patients (40 hips) with SL-PLUS prosthesis (control group) during the same period. There was no significant difference in gender, age, disease duration, etiology, preoperative range of motion (ROM) of hip, and preoperative Harris score between 2 groups (P > 0.05). The incision length, operation time, and intraoperative blood loss were recorded during operation. The improvement of hip joint function was evaluated according to Harris score criteria. The ROM of hip was measured, and the X-ray film was taken to observe the position of prosthesis. RESULTS: Trial group had shorter incision length, less operation time, and less intraoperative blood loss than control group, showing significant differences (P < 0.05). All wounds healed by first intention. All patients were followed up 10-16 months (mean, 13.6 months). During follow-up, 5 cases (5 hips) of control group and 3 cases (3 hips) of trial group still had pain of hips. At last follow-up, the ROM of hip was (152.48 +/- 9.68) degrees in trial group and (152.16 +/- 8.18) degrees in control group, the Harris score was 91.4 +/- 2.9 in trial group and 90.9 +/- 1.8 in control group; there were significant differences when compared with preoperative values (P < 0.05), but no significant difference was found between 2 groups (P > 0.05). X-ray films showed good position of the prosthesis with no displacement, loosening, or subsidence in both groups. CONCLUSION: SL-PLUS MIA femoral stem prosthesis has less surgical trauma and blood loss than SL-PLUS prosthesis during THA. The short-term effectiveness is satisfactory, but the long-term effectiveness still needs further observation.

[Correlation between expression of aquaporins 1 and chondrocyte apoptosis in articular chondrocyte of osteoarthritis].

OBJECTIVE: The changes of the aquaporins 1 (AQP-1) expression may be related to the chondrocyte apoptosis. To explore the correlation between the expression of AQP-1 and chondrocyte apoptosis by observing the expression of the AQP-1 and the Caspase-3, so as to provide experimental evidence for the further study in the pathogenesis of osteoarthritis (OA). METHODS: Seventy-two 8-week-old clean grade male Sprague Dawley rats, weighing 286-320 g (mean, 300 g), were randomly divided into the operated group (n = 24), the sham-operated group (n = 24), and the control group (n = 24). OA models were made by amputating the anterior cruciate ligament and medial collateral ligament, and partial excision of medial meniscus in operated group; the articular cavity was exposed only in sham-operated group; and no treatment was given in control group. The general condition of the rat was observed after model was established. At 1, 2, 4, and 8 weeks, the specimens of knee joints were harvested to perform the gross and histological observations; the mRNA expressions of AQP-1 and Caspase-3 were determined by real-time fluorescent quantitative PCR; and the activity of the Caspase-3 protease was detected. The correlations between the expression of AQP-1 mRNA and the expressions of Caspase-3 mRNA and protease were analyzed. RESULTS: Totally 6 rats died after operation, and the rats were supplied immediately; the other rats survived to the end of experiment. The appearance and structure of knee articular cartilage were normal in control group and sham-operated group. While in operated group, the cartilage had a rough surface with fissure and vegetation, and fibrosis and irregular cell arrangement were seen on the surface of cartilage. There were significant differences in the Mankin score between the operated group and sham-operated group, control group at 2, 4, and 8 weeks (P < 0.05). There was no significant difference in expressions of the AQP-1 mRNA and Caspase-3 mRNA, and the activity of the Caspase-3 protease among 3 groups at 1 week after operation (P > 0.05); while the expressions of the AQP-1 mRNA, Caspase-3 mRNA, and the activity of the Caspase-3 protease in operated group were significantly higher than those in sham-operated group and control group at 2, 4, and 8 weeks after operation (P < 0.05), and there was an increased trend over time. There was significantly positive correlation (r = 0.817, P = 0.000) between the expressions of AQP-1 mRNA and Caspase-3 mRNA, and the regression equation was y = 0.426 7x(2) + 0.051 5x; meanwhile, there was also significantly positive correlation (r = 0.945, P = 0.000) between the expression of AQP-1 mRNA and the activity of Caspase-3 protease, and the regression equation was y = 15.423 0x + 4.392 8. CONCLUSION: The up-regulation of AQP-1 expression in OA cartilage may be related to the chondrocyte apoptosis, and the changes of AQP-1 expression may involve in the pathogenesis of OA.

Design of antiangiogenic hypoxic cell radiosensitizers: 2-nitroimidazoles containing a 2-aminomethylene-4-cyclopentene-1,3-dione moiety.

We designed chiral 2-nitroimidazole derivatives containing a 2-aminomethylene-4-cyclopentene-1,3-dione moiety as antiangiogenic hypoxic cell radiosensitizers. Based on results of molecular orbital calculations, the 2-aminomethylene-4-cyclopentene-1,3-dione moiety is expected to show high electrophilicity comparable to that of the 2-methylene-4-cyclopentene-1,3-dione moiety included in TX-1123 and tyrphostin AG17. We evaluated the antiangiogenic and radiosensitizing effects of the new compounds, along with other biological properties including their activities as hypoxic cytotoxicities and protein tyrosine kinase (PTK) inhibitory activities. Among the compounds tested, 5 (TX-2036) proved to be the strongest antiangiogenic hypoxic cell radiosensitizer. All the other chiral 2-nitroimidazole derivatives having 2-aminomethylene-4-cyclopentene-1,3-dione moiety tested were also antiangiogenic hypoxic cell radiosensitizers. The PTK inhibitory activity of 5 (TX-2036) showed this to be a promising and potent EGFR kinase inhibitor, having an IC(50) value of lower than 2microM. This compound also was an Flt-1 kinase inhibitor having an IC(50) value of lower than 20microM. Our results show that these chiral 2-nitroimidazole derivatives that contain the 2-aminomethylene-4-cyclopentene-1,3-dione moiety as a potent antiangiogenic pharmacophoric descriptor are promising lead candidates for the development of antiangiogenic hypoxic cell radiosensitizers.

Angiogenesis inhibitor TX-1898: syntheses of the enantiomers of sterically diverse haloacetylcarbamoyl-2-nitroimidazole hypoxic cell radiosensitizers.

(R)- and (S)-Epichlorohydrins were used to prepare the enantiomers of sterically diverse haloacetylcarbamoyl-2-nitroimidazoles that function as hypoxic cell radiosensitizers. The synthetic design allowed for introduction of a side chain of varying bulk that permitted an examination of the steric effects on enantio-discrimination in biological assay systems. The single stereocenter also connected the two pharmacophores--a 2-nitroimidazole moiety critical to hypoxic cell radiosensitization, and a haloacetylcarbamoyl group to function as an anti-angiogenesis pharmacophore. In the chick embryo chorioallantoic membrane (CAM) assay, the R-enantiomers possessing the bulky p-tert-butylphenyl group showed higher anti-angiogenic activity than the corresponding S-enantiomers, while there were no differences in the activity between the enantiomers containing the less bulky methyl and tert-butyl groups. Among the compounds we report, R-p-tert-butylphenyl-bromoacetylcarbamoyl-2-nitroimidazole, TX-1898, was found to be the most promising candidate for further development of as anti-angiogenic hypoxic cell radiosensitizer.