Qiande Liao

Meta-analysis of limb salvage versus amputation for treating high-grade and localized osteosarcoma in patients with pathological fracture

The goal of this study was to determine outcomes related to limb salvage vs. amputation for treating high-grade and localized osteosarcoma in patients with pathological fractures. Literature search was conducted using Medline, Embase and the Cochrane Database. Two reviewers independently assessed all eligible publications. The primary outcome measurement was pooled odds ratio (OR) and 95% confidence interval (CI) for the risk of local recurrence, 5-year overall survival rate and metastatic occurrence calculated through the fixed-effects method. Seven eligible studies were identified, which included a total of 284 patients. The risk for local recurrence and 5-year overall survival rate did not differ significantly (P>0.05) between the limb salvage group and amputation group, with an OR of 1.48 (95% CI, 0.67–3.30) and 1.85 (95% CI, 0.86–3.98), respectively. The risk for metastatic occurrence differed significantly (P<0.05), with an OR of 0.30 (95% CI, 0.10–0.91). The occurrence of a pathological fracture is not regarded as an absolute contraindication to limb salvage in patients with high-grade and localized osteosarcoma. Limb salvage as an alternative for treating high-grade and localized osteosarcoma in patients with pathological fracture does not greatly increase the risk for local recurrence or 5-year overall survival rate compared to amputation and has a lower risk for metastatic occurrence.

T lymphocyte subset imbalances in patients contribute to ankylosing spondylitis

Ankylosing spondylitis is a chronic inflammatory rheumatic disease, which is characterized by inflammation of the spine and the sacroiliac joints. To date, the disease etiology remains unclear. In the present study, the correlation of T lymphocyte subset changes with the progression of ankylosing spondylitis was investigated. A total of 55 patients with ankylosing spondylitis (22 severe and 23 mild cases) and 20 healthy individuals were selected. Firstly, the punctured cells in the lesions and the serum were collected, and the lymphocytes and the peripheral blood mononuclear cells were prepared. Secondly, quantitative PCR, ELISA and flow cytometry analyses were carried out to detect the levels of a series of immunoglobulins, complements, helper T cells, cytotoxic T cells, regulatory cells and cytokines. The expression levels of α-globulin, γ-globulin, immunoglobulin (Ig)G, IgA, IgM, serum complement C3, and complement C4 were found to be significantly increased in ankylosing spondylitis patients. In addition, the percentage of Th1 and Th17 cells was found to be significantly higher in the ankylosing spondylitis groups (mild and severe) compared with the healthy individuals. As a result, the Th1/Th2 and Th17/Treg ratios were significantly higher in patients with ankylosing spondylitis. In addition, T lymphocyte subset ratio imbalances contributed to an increased expression of immune mediators, including interferon (IFN)-γ and interleukin (IL)-17A. The mRNA and protein expression levels of IFN-γ and IL-17A were found to be higher in the ankylosing spondylitis groups compared with the control group. The present study provided further evidence on the function and underlying mechanism of T lymphocyte subsets, which may be useful in the diagnosis and treatment of ankylosing spondylitis.

TWIST interacts with β‐catenin signaling on osteosarcoma cell survival against cisplatin

Both TWIST and Wnt/β‐catenin signaling reportedly play important roles in osteosarcoma development. In the present study, we explored the regulatory effect of TWIST on β‐catenin in osteosarcoma cells and assessed how the functional interaction between TWIST and β‐catenin would impact osteosarcoma cell survival against chemotherapy agent cisplatin. Overexpression and knockdown of TWIST were respectively performed in Saos‐2 and MG‐63 osteosarcoma cells. Overexpression of TWIST in Saos‐2 cells significantly decreased the soluble β‐catenin level, phosphorylation of glycogen synthase kinase‐3β (GSK‐3β) at serine 9, the mRNA level of β‐catenin signaling target genes, and cell survival against cisplatin, which was strengthened by knocking down β‐catenin. Knockdown of TWIST in MG‐63 cells significantly increased the soluble β‐catenin level, phosphorylation of GSK‐3β at serine 9, the mRNA level of β‐catenin signaling target genes, and cell survival against cisplatin, which was reversed by knocking down β‐catenin or phosphatidylinositol 3‐kinase (PI3K) inhibitor LY294002. In conclusion, we demonstrate that TWIST decreases osteosarcoma cell survival against cisplatin by decreasing the soluble β‐catenin level through a PI3K‐dependent manner. This study provides the first evidence of a functional link between TWIST and β‐catenin signaling in osteosarcoma cells, which adds fresh insights into the molecular mechanism of osteosarcoma development.

Procalcitonin levels in fresh serum and fresh synovial fluid for the differential diagnosis of knee septic arthritis from rheumatoid arthritis, osteoarthritis and gouty arthritis.

Whether the levels of procalcitonin (PCT) in the serum and synovial fluid are effective indicators for distinguishing septic arthritis (SA) from non-infectious arthritis remains controversial. The present study aimed to evaluate whether PCT levels in fresh serum or fresh joint fluid may be used in the differential diagnosis of SA from rheumatoid arthritis (RA), osteoarthritis (OA) and gouty arthritis (GA). From January 2012 to June 2013, 23 patients with knee SA, 21 patients with RA, 40 patients with OA and 11 patients with GA were enrolled in the current study. The levels of PCT were measured within 24 h after specimen collection at room temperature. An enzyme-linked fluorescence assay (ELFA) was used to detect the levels of PCT in the serum and synovial fluid. The correlations between the levels of PCT in the serum and synovial fluid and the arthritic patient groups were determined by the Nemenyi test. Areas under the receiver operating characteristic (ROC) curve were calculated to evaluate the accuracy of the correlations. The levels of PCT in the serum and joint fluid of the patients in the SA group were higher compared with those of the other groups (P<0.01) and there were no significant differences among the RA, OA and GA groups in these levels. A PCT level of <0.5 μg/l in the serum and synovial fluid had high specificity in the differential diagnosis of SA from RA, OA and GA. Synovial fluid PCT revealed significantly greater sensitivity than serum PCT. The accuracy of the differential diagnosis of SA by the serum levels of PCT was significantly lower than that by the synovial fluid levels of PCT. The levels of PCT in the serum and synovial fluid may be used as alternative laboratory indicators to distinguish between SA and the non-infectious types of arthritis; however, the PCT levels in fresh synovial fluid are more sensitive and accurate indicators than PCT levels in fresh serum.

Preparation of a new composite combining strengthened β‑tricalcium phosphate with platelet‑rich plasma as a potential scaffold for the repair of bone defects

β-tricalcium phosphate (β-TCP) and platelet-rich plasma (PRP) are commonly used in bone tissue engineering. In the present study, a new composite combining strengthened β-TCP and PRP was prepared and its morphological and mechanical properties were investigated by scanning electron microscopy (SEM) and material testing. The biocompatibility was evaluated by measuring the adhesion rate and cytotoxicity of bone marrow stromal cells (BMSCs). The strengthened β-TCP/PRP composite had an appearance like the fungus Boletus kermesinus with the PRP gel distributed on the surface of the micropores. The maximum load and load intensity were 945.6±86.4 N and 13.1±0.5 MPa, which were significantly higher than those of β-TCP (110.1±14.3 N and 1.6±0.2 MPa; P<0.05). The BMSC adhesion rate on the strengthened β-TCP/PRP composite was >96% after 24 h, with a cell cytotoxicity value of zero. SEM micrographs revealed that following seeding of BMSCs onto the composite in high-glucose Dulbecco’s modified Eagle’s medium culture for two weeks, the cells grew well and exhibited fusiform, spherical and polygonal morphologies, as well as pseudopodial connections. The strengthened β-TCP/PRP composite has the potential to be used as a scaffold in bone tissue engineering due to its effective biocompatibility and mechanical properties.

In vivo ossification of a scaffold combining β‑tricalcium phosphate and platelet‑rich plasma

Tricalcium phosphate (TCP) and platelet-rich plasma (PRP) are commonly used in bone tissue engineering. The aim of the present study was to investigate a composite that combined TCP with PRP and assess its effectiveness in the treatment of bone defects. Cavity-shaped bone defects were established on the tibiae of 27 beagle dogs, and were repaired by pure β-TCP with bone marrow stromal cells (BMSCs), β-TCP/PRP with BMSCs and autogenic ilium. The samples were harvested at 4, 8 and 12 weeks, and bone regeneration was evaluated using X-ray radiography, immunocytochemical staining of osteocalcin (OCN), hematoxylin and eosin staining and reverse transcription-polymerase chain reaction analyses. Biomechanical tests of the scaffolds were performed at the 12th week after scaffold implantation. When using pure β-TCP as a scaffold, the scaffold-bone interface was clear and no material adsorption and bone healing was observed. Substantial bone regeneration was observed when the tibial defects were restored using β-TCP/PRP and autogenic ilium. Furthermore, the mRNA expression levels of OCN, alkaline phosphatase and collagen type I α1 were significantly higher in the animals with β-TCP/PRP scaffolds at 8 and 12 weeks following implantation compared with those in the animals with the pure β-TCP scaffolds. The maximum load and compressive strength of the β-TCP/PRP scaffolds were similar to those of the autogenic ilium; however, they were significantly higher than those of the pure β-TCP scaffold. Thus, the β-TCP/PRP composite may be used as a potential scaffold to carry in vitro cultured BMSCs to treat bone defects.

In vivo testing of porous Ti-25Nb alloy serving as a femoral stem prosthesis in a rabbit model.

The aim of the present study was to observe the performance of Ti-25Nb alloys with various porosities as femoral stem prostheses in a rabbit model, thus providing basic experimental evidence for the development of porous prostheses. The porous Ti-25Nb alloy prostheses were designed according to the morphology of the medullary cavity. These prostheses were placed into the femoral medullary cavities in 36 New Zealand white rabbits. Postoperative X-ray films, scanning electron microscopy (SEM) of the implant interface, energy-dispersive spectroscopy (EDS) analysis of the implant surface, pulling-out test and general observations were conducted. The specimens showed good biocompatibility; there was no obvious bone absorption in porous Ti-25Nb specimens with different porosities at different time points observed using X-ray films. Under SEM examination, calcium deposits were observed inside the pores and in the interface between bone and prostheses. The EDS analysis demonstrated that calcium deposits were present on the surface of the prostheses at the eight-week point postoperatively. The pulling-out test showed good bonding strength between bone and implant; after pulling out, the surface and inside the pores of the prostheses all presented bone mass. Porous Ti-25Nb alloy implants presents good biocompatibility as well as providing a biological fixation between the bone and implant. A porosity of 70% is more advantageous to the newborn bone ingrowth, combined with achieving a more solid bone-implant interface.

Clinical analysis of prosthesis replacement for proximal humerus tumors

OBJECTIVE To explore surgical strategies, functions and prognosis of artificial prosthesis replacement and soft tissue reconstruction for patients with invasive benign or primary malignant proximal humerus tumor.
 METHODS A total of 17 patients with invasive benign or primary malignant proximal humerus tumor underwent prosthetic replacement after segment bone tumor resection and soft tissues reconstruction from April 2007 to April 2014 were enrolled. Based on histological types, tumor stages and surgical procedures, the effects of artificial prosthesis replacement and soft tissue reconstruction on prognosis and shoulder joint function were evaluated.
 RESULTS All patients were followed up for 8 to 96 months (average time: 58.9 months). Among 11 patients with primary malignant tumor, 5 died of tumor recurrence or metastasis, and 6 showed tumor-free survival for 24 to 91 months (average time: 54.83 months). The 6 patients with aggressive benign tumors survived for 39 to 96 months, with an average of 72.33 months. The shoulder joint function of 17 patients recovered to 64.88% of normal. There were significant differences in the shoulder joint function between the patients who underwent half shoulder replacement and those who underwent total shoulder replacement (56.25% vs 72.56%, P<0.05). There were significant differences in the shoulder joint function between the patients who underwent Type I A excision (retention of abductor muscles and rotator cuff) and those who underwent Type I B excision (68.75% vs 61.44%, P<0.05).
 CONCLUSION The survival of patients with invasive benign or primary malignant proximal humerus, who underwent artificial prosthesis replacement and soft tissue reconstruction, is closely related to tumor types. The shoulder joint function is associated with the methods of prosthesis replacement and soft tissue resection.

Treatment of Tile B pelvic fracture by external fixator combined with limited internal fixation

OBJECTIVE To determine the effectiveness of external fixator combined with limited internal fixation for Tile B pelvic fractures. METHODS Fourteen patients with Tile B pelvic fracture were treated by external fixator combined with limited internal fixation between September 2004 and June 2009. RESULTS All the patients were followed for 6-49 (20.2 +/- 10.2) months. According to the Matta standard, the outcome of 9 patients was excellent, 4 patients were good, while the other one patient was fair. CONCLUSION External fixator combined with limited internal fixation is effective for Tile B pelvic fracture. It can not only reduce the anatomic position of the pelvis, but also strengthen the stability of the pelvis as a whole. This method is less invasive and traumatic, which promotes the recovery of patients.