A20 inhibits the release of inflammatory cytokines by suppressing the activation of the nuclear factor-kappa B pathway in osteoarthritic fibroblast-like synoviocytes.

A growing number of studies suggest that synovitis plays an important role in the pathogenesis and progression of osteoarthritis (OA). As a negative mediator of the nuclear factor-kappa B (NF-κB) signaling pathway, the zinc finger protein A20 has significant anti-inflammatory properties. In this study, the differential expression of A20 was investigated at the mRNA and protein levels in human normal OA fibroblast-like synoviocytes (FLSs) and normal FLSs pretreated with TNF-α. We then measured the activation of the NF-κB pathway and expression of pro-inflammatory cytokines in the above three groups by western blotting, a human cytokine array and ELISA. We found that TNF-α activated the NF-κB pathway, increased the expression of the pro-inflammatory cytokines IL-6 and IL-8, and A20 expression in human normal FLSs. However, the role of A20 in FLSs was unclear. To clarify this, we investigated the effect of A20 overexpression in human normal FLSs. The results indicate that A20 inhibits the NF-κB signaling pathway activation and OA-associated pro-inflammatory cytokines release. The results of this study indicate that A20 has anti-inflammatory effects in FLSs, which makes it a potential target for OA synovitis treatment.

Ryanodine Receptor 2 Plays a Critical Role in Spinal Cord Injury via Induction of Oxidative Stress.

BACKGROUND/AIMS: Spinal cord injury (SCI) is a severe health problem worldwide. Ryanodine receptors (RyRs) are a class of intracellular calcium channels in various excitable tissues such as muscles and nervous tissues. The current study was designed to investigate the possible role of RyR2 upregulation in SCI and to elucidate the possible molecular mechanisms. METHODS: Rats were injected with LVshRNAi- RyR2 and then exposed to spinal cord contusion injury. RESULTS: The results showed that knockdown of RyR2 significantly promoted the recovery of structural and functional injury in spinal cord, as evidenced by reduction of lesion volume and increase of Basso, Beattie and Bresnahan (BBB) and combined behavioral score (CBS) scores. Knockdown of RyR2 inhibited the increase of proinflammatory cytokines, including IL-1ß and TNFα. Moreover, downregulation of RyR2 increased oxygen consumption rate and decreased the expression of glucose-regulated protein 78 (GRP78), activating transcription factor 3 (ATF3) and ATF6, indicating the improvement of mitochondrial dysfunction and endoplasmic reticulum stress after SCI. Furthermore, silence of RyR2 reduced oxidative stress, as reflected by decrease of TBARS and GSSG content and increase of GSH level. The expression of NADPH oxidase 2 (NOX2), NOX4 and p66(shc) were increased in SCI rats. Knockdown of RyR2 significantly decreased NOX2 expression, but had no evident effect on NOX4 and p66shc expression. These results indicated NOX2 may be involved in RyR2-induced ROS generation which mediated contusion-induced spinal cord injury. CONCLUSION: The data provide novel insights into the mechanism of RyR2-mediated injury and the potential therapeutic targets for injury in spinal cord.

Meta-Analysis of Outcomes of a Single-Radius Versus Multi-Radius Femoral Design in Total Knee Arthroplasty.

BACKGROUND: Although the single-radius (SR) femoral design is known to have theoretical advantages in many aspects, studies of clinical outcomes that compare the SR with the multiple-radius (MR) femoral design are controversial. We performed a meta-analysis to address the hypothesis that a SR femoral design in primary total knee arthroplasty improves patient outcomes. METHODS: The meta-analysis identified 15 articles reporting the clinical outcomes of 2212 knee replacements using the SR (n = 948) compared with the multiradius (MR; n = 1361) femoral design. Comparing SR with MR, we examined the Knee Society Score for the knee (KSS-knee), KSS-function, knee flexion, range of motion, complications, isometric peak torque of knee, and survival rate. RESULTS: The range of motion of SR knees was lower than that of MR knees. No differences were found in the analyses of KSS-knee, KSS-function, knee flexion, complications, isometric peak torque of the knee, and survival rate. CONCLUSION: Our meta-analysis does not provide clinical support for the previously reported theoretical advantages of the SR implant design.

Proteomic profiling of osteosarcoma cells identifies ALDOA and SULT1A3 as negative survival markers of human osteosarcoma.

Osteosarcoma (OSA) is the most common primary malignancy of bone. Molecular mechanism underlying OSA remains to be fully elucidated. It is critical to identify reliable diagnostic and prognostic markers for OSA at the molecular levels. This study is designed to investigate possible molecular mechanisms behind OSA development and to identify novel prognostic markers related to OSA survival. We conduct a comprehensive proteomic profiling analysis of human OSA cell lines with differential metastatic potential. Through comprehensive combinatorial analyses of the proteomic data and the previously obtained cDNA microarray results, we identify 37 candidate proteins which are differentially expressed in OSA sublines. Among them, ALDOA and SULT1A3 are selected for further investigation. The expressions of protein are confirmed by Western blotting analysis. We further analyze the expression levels of ALDOA and SULT1A3 from 40 clinical cases of OSA. The results demonstrate that the expression of ALDOA and/or SULT1A3 is significantly higher in patients with worse survival time than patients with better survival time. Five-year survival analysis shows there is a statistically significant difference between two patient populations. The data strongly suggest that ALDOA and/or SULT1A3 expression level in biopsy samples may predict the clinical outcomes of OSA patients. Furthermore, the biological functions of ALDOA and SULT1A3 may be implicated in OSA development and/or progression.

Sequential surgery for the treatment of type I knee ankylosis: a series of 62 cases.

BACKGROUNDS: The lack of systematic classification and standard treatment principles for knee ankylosis prevents optimal treatments. This study explored treatments for type I (mild) knee joint ankylosis. METHOD: This retrospective study analysed patients with knee joint ankylosis admitted from March 2013 to January 2018 who underwent sequential arthroscopic release. RESULT: The 62 patients had 12-36 (average, 18) months of follow-up. Thirty-eight patients were released; of these, 18 were assisted by limited incision with partial quadriceps femoris expansion myotomy and released according to arthroscopy. Six patients underwent lengthening and release of the quadriceps femoris. All surgeries combined with full-course rehabilitation resulted in improved joint mobility. The range of motion (ROM) of the knee joint recovered to a range of 0° to 85°-140° (mean: 118.32 ± 9.42°) from the preoperative range of 30°-70° (mean: 45° ± 15.50°). The clinical effect was evaluated according to the Judet criteria at the final follow-up. The outcomes at the last follow-up (at least for 1 year) were excellent in 55 cases, good in six cases, and fair in one case. CONCLUSION: Sequential arthroscopic release, minimal selective invasion of limited incision of partial quadriceps femoris expansion myotomy, assisted by pie-crusting technique to release, or quadriceps femoris lengthening, and release surgery for type I knee joint ankylosis, accompanied by early rehabilitation training provided satisfactory results without significant complications.

Long noncoding RNA NAV2-AS5 relieves chondrocyte inflammation by targeting miR-8082/TNIP2 in osteoarthritis.

Osteoarthritis (OA) is a common chronic and frequently occurring orthopedic disease in the middle-aged and elderly individuals. Numerous studies have shown that long noncoding RNAs (lncRNAs) play major roles in various diseases. However, the potential molecular mechanism of action of NAV2-AS5 in OA remains unclear. The present study was designed to explore the influence of NAV2-AS5 on the progression of chondrocyte inflammation and its underlying molecular mechanisms. To simulate the inflammatory environment in OA, the human chondrocyte cell line was treated with LPS. Cell proliferation, cell cycle progression, and apoptosis were assessed using Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine analysis, and flow cytometry. Proliferation- and cycle-related proteins and the release of inflammatory factors were examined by western blot analysis and enzyme-linked immunosorbent assay. The downstream targets of NAV2-AS5 were determined using bioinformatics and confirmed by a luciferase reporter assay. In our study, patients with OA showed downregulation of NAV2-AS5, upregulation of miR-8082, and downregulation of TNFAIP3 interacting protein 2 (TNIP2). Moreover, we found that both overexpression of NAV2-AS5 and miR-8082 inhibitor promoted cell proliferation, inhibited apoptosis, and released inflammatory cytokines in LPS-treated chondrocytes. MiR-8082 was predicted to be a target of both NAV2-AS5 and TNIP2. In addition, rescue experiments showed that silencing of TNIP2 reversed the effects of the miR-8082 inhibitor on proliferation, cell cycle, apoptosis, and inflammatory factors in sh-NAV2-AS5-treated chondrocytes. In conclusion, these findings indicate that NAV2-AS5 relieves chondrocyte inflammation by targeting miR-8082/TNIP2 in OA, which provides a new theoretical basis for OA therapy.

Irreversible Electroporation Improves Tendon Healing in a Rat Model of Collagenase-Induced Achilles Tendinopathy.

BACKGROUND: Treatment of painful chronic tendinopathy is challenging, and there is an urgent need to develop new regenerative methods. Irreversible electroporation (IRE) can lead to localized cell ablation by electrical pulses and induce new cell and tissue growth. Previously, the authors' group reported that electroporation-ablated tendons fully regenerated. PURPOSE: To assess the efficiency of IRE in improving tendon healing using a collagenase-induced Achilles tendinopathy rat model. STUDY DESIGN: Controlled laboratory study. METHODS: After screening for the IRE ablation parameters, a collagenase-induced Achilles tendinopathy rat model was used to assess the efficacy of IRE in improving tendon healing via biomechanical, behavioral, histological, and immunofluorescence assessments. RESULTS: The experiments showed that the parameter of 875 V/cm 180 pulses could ablate most tenocytes, and apoptosis was the main type of death in vitro. In vivo, IRE promoted the healing process of chronic tendinopathy in the Achilles tendon of rats, based on biomechanical, behavioral, and histological assessments. Finally, immunofluorescence results revealed that IRE improved blood supply in the early stages of tendon repair and could potentially reduce neuropathic pain. CONCLUSION: IRE enhanced tendon tissue healing in a rat model of collagenase-induced Achilles tendinopathy. CLINICAL RELEVANCE: IRE may as a potential alternative treatment for tendinopathy in clinical usage.

Dose-Response Relationships of Resistance Training in Adults With Knee Osteoarthritis: A Systematic Review and Meta-analysis.

BACKGROUND AND PURPOSE: To determine the effects of resistance training (RT) on symptoms, function, and lower limb muscle strength in patients with knee osteoarthritis (KOA), and to determine the optimal dose-response relationships. DATA SOURCES: We searched the PubMed, MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and ClinicalTrials.gov databases from inception to January 23, 2022. ELIGIBILITY CRITERIA: Randomized controlled trials that examined the effects of RT in KOA patients (mean age ≥50 years) were included. DATA SYNTHESIS: We applied Hedges' g of the random-effects model to calculate the between-subject standardized mean difference (SMDbs). A random-effects metaregression was calculated to explain the influence of key training variables on the effectiveness of RT. We used the Grading of Recommendations Assessments, Development and Evaluation (GRADE) method to appraise the certainty of evidence. RESULTS: A total of 46 studies with 4289 participants were included. The analysis revealed moderate effects of RT on symptoms and function (SMDbs =-0.52; 95% CI: -0.64 to -0.40), and lower limb muscle strength (SMDbs = 0.53; 95% CI: 0.42 to 0.64) in the intervention group compared with the control group. The results of the metaregression revealed that only the variable "training period" (P< .001) had significant effects on symptoms, function, and lower limb muscle strength, and the 4 to 8 weeks of training subgroup showed greater effects than other subgroups (SMDbs =-0.70, -0.91 to -0.48; SMDbs = 0.76, 0.56 to 0.96). CONCLUSIONS: Compared with inactive treatments, RT is strongly recommended to improve symptoms, function, and muscle strength in individuals with KOA. Dose-response relationship analysis showed that 4 to 8 weeks of RT had more benefits.

Healthcare and Scientific Treatment of Knee Osteoarthritis.

Knee osteoarthritis is a chronic degenerative disease companied with chronic knee pain and dysfunction. However, the etiology and pathogenesis of knee osteoarthritis were unclear. Currently, age, diet, trauma, obesity, and inheritance are the main risk factors. The major pathological hallmarks of knee osteoarthritis included subchondral bone sclerosis, articular cartilage degeneration, arthrosynovitis, and osteophyte. With the acceleration of the aging process in China, the treatment of knee arthritis and the methods to improve the quality of life have become the focus of medical staff. Currently, therapies in clinical practice include surgery and nonoperative treatment; however, the clinical effects of different individuals at different stages will still be very different. This article reviews the recent advances in the treatment of knee osteoarthritis from three aspects: nonsurgical treatment, surgical treatment, and modern new medical means.

Pan-Cancer Transcriptome and Immune Infiltration Analyses Reveal the Oncogenic Role of Far Upstream Element-Binding Protein 1 (FUBP1).

Despite increasing evidence to support the relationship between FUBP1 and tumorigenesis in some types of cancers, there have been no analyses from a pan-cancer perspective. Here, we are the first to investigate the putative oncogenic role of FUBP1 in 33 cancer types based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Dysregulated FUBP1 expression was observed in most cancer types, and high FUBP1 expression suggests poor prognosis in cancers such as ACC, KICH, LIHC, LUAD, LUSC, SARC, CESC, and SKCM. Missense mutation is the most common type of FUBP1 mutation, and R430 in KH_4 is a predominant mutation site. Enhanced phosphorylation of FUBP1 at the S120 site has been observed in clear cell RCC, lung adenocarcinoma, and pediatric brain cancer specimens from African-American and Asian individuals. The expression of FUBP1 was found to be negatively correlated with the infiltration of CD8+ T lymphocytes in GBM, HNSC-HPV- and UCEC but positively correlated with that of tumor-associated fibroblasts in CESC, ESCA, HNSC, LIHC, LUAD, PAAD, and THYM. Furthermore, RNA splicing and spliceosome signaling were predominantly enriched in both GO and KEGG analyses of the functional mechanism of FUBP1. Briefly, this pan-cancer analysis comprehensively revealed the multifaceted characteristics and oncogenic role of FUBP1 in different human cancers.

MicroRNA expression during osteogenic differentiation of human multipotent mesenchymal stromal cells from bone marrow.

MicroRNAs comprise a group of non-coding small RNAs (17-25 nt) involved in post-transcriptional regulation that have been identified in various plants and animals. Studies have demonstrated that miRNAs are associated with stem cell self-renewal and differentiation and play a key role in controlling stem cell activities. However, the identification of specific miRNAs and their regulatory roles in the differentiation of multipotent mesenchymal stromal cells (MSCs) have so far been poorly defined. We isolated and cultured human MSCs and osteo-differentiated MSCs from four individual donors. miRNA expression in MSCs and osteo-differentiated MSCs was investigated using miRNA microarrays. miRNAs that were commonly expressed in all three MSC preparations and miRNAs that were differentially expressed between MSCs and osteo-differentiated MSCs were identified. Four underexpressed (hsa-miR-31, hsa-miR-106a, hsa-miR-148a, and hsa-miR-424) and three novel overexpressed miRNAs (hsa-miR-30c, hsa-miR-15b, and hsa-miR-130b) in osteo-differentiated MSCs were selected and their expression were verified in samples from the fourth individual donors. The putative targets of the miRNAs were predicted using bioinformatic analysis. The four miRNAs that were underexpressed in osteo-differentiated MSCs were predicted to target RUNX2, CBFB, and BMPs, which are involved in bone formation; while putative targets for miRNAs overexpressed in osteo-differentiated MSCs were MSC maker (e.g., CD44, ITGB1, and FLT1), stemness-maintaining factor (e.g., FGF2 and CXCL12), and genes related to cell differentiation (e.g., BMPER, CAMTA1, and GDF6). Finally, hsa-miR-31 was selected for target verification and function analysis. The results of this study provide an experimental basis for further research on miRNA functions during osteogenic differentiation of human MSCs.

An experimental study on stress-shielding effects of locked compression plates in fixing intact dog femur.

BACKGROUND: In orthopedic application, stress-shielding effects of implant materials cause bone loss, which often induces porosis, delayed bone healing, and other complications. We aimed to compare the stress-shielding effects of locked compression plate (LCP) and limited-contact dynamic compression plate (LC-DCP) in dogs with plate-fixed femurs. METHODS: Bilateral intact femurs of 24 adult dogs were fixed by adult forearm 9-hole titanium plates using minimally invasive plate osteosynthesis (MIPPO) technology, with LCP on the left and LC-DCP on the right femurs. Dogs were sacrificed at 6 weeks, 12 weeks, and 24 weeks after surgery, and bone specimens were used to evaluate the efficacies of different fixing methods on bones through X-ray, dual-energy X-ray absorptiometry (DEXA), histology, MicroCT, and biomechanics analyses. RESULTS: X-ray results showed significant callus formation and periosteal reaction in the LC-DCP group. Bone cell morphology, degree of osteoporosis, and bone mineral density (BMD) changes of the LCP group were significantly better than that of the LC-DCP group. MicroCT results showed that the LCP group had significantly reduced degree of cortical bone osteoporosis than the LC-DCP group. Tissue mineral density (TMD) in the LCP group was higher than that in the LC-DCP group at different time points (6 weeks, 12 weeks, and 24 weeks). Biomechanics analyses demonstrated that the compressive strength and flexural strength of bones fixed by LCP were better than that by LC-DCP. CONCLUSIONS: Stress-shielding effects of LCP are significantly weaker than that of LC-DCP, which is beneficial to new bone formation and fracture healing, and LCP can be widely used in clinic for fracture fixation.

Hydroxysafflor Yellow A protects spinal cords from ischemia/reperfusion injury in rabbits.

BACKGROUND: Hydroxysafflor Yellow A (HSYA), which is one of the most important active ingredients of the Chinese herb Carthamus tinctorius L, is widely used in the treatment of cerebrovascular and cardiovascular diseases. However, the potential protective effect of HSYA in spinal cord ischemia/reperfusion (I/R) injury is still unknown. METHODS: Thirty-nine rabbits were randomly divided into three groups: sham group, I/R group and HSYA group. All animals were sacrificed after neurological evaluation with modified Tarlov criteria at the 48th hour after reperfusion, and the spinal cord segments (L4-6) were harvested for histopathological examination, biochemical analysis and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining. RESULTS: Neurological outcomes in HSYA group were slightly improved compared with those in I/R group. Histopathological analysis revealed that HSYA treatment attenuated I/R induced necrosis in spinal cords. Similarly, alleviated oxidative stress was indicated by decreased malondialdehyde (MDA) level and increased superoxide dismutase (SOD) activity after HSYA treatment. Moreover, as seen from TUNEL results, HSYA also protected neurons from I/R-induced apoptosis in rabbits. CONCLUSIONS: These findings suggest that HSYA may protect spinal cords from I/R injury by alleviating oxidative stress and reducing neuronal apoptosis in rabbits.

Association between TGFBR1*6A and osteosarcoma: a Chinese case-control study.

BACKGROUND: TGFBR1*6A is a common hypomorphic variant of transforming growth factor beta receptor 1 (TGFBR1). TGFBR1*6A is associated with an increased cancer risk, but the association of this polymorphism with osteosarcoma remains unknown. We have measured the frequency of TGFBR1*6A variants in osteosarcoma cases and controls. METHODS: Our case-control study is based on 168 osteosarcoma patients and 168 age- and gender-matched controls. Blood samples were obtained and the TGFBR1*6A variant determined by PCR amplification and DNA sequencing. The odds ratio (OR) and 95% confidence interval (95% CI) for the TGFBR1*6A polymorphism were calculated by unconditional logistic regression, adjusted for both age and gender. Three models - dominant, additive and recessive - were used to analyze the contribution of the TGFBR1*6A variant to osteosarcoma susceptibility. RESULTS: Heterozygotic and homozygotic TGFBR1*6A variants represented 50.4% and 6.0% of the 168 cases, whereas the controls had 18. 5% and 1.3%, respectively. ORs for homozygosity and heterozygosity of the TGFBR1*6A allele were 4.6 [95% CI, 2.33-7.97] and 2.9 [95% CI, 1.59-5.34] in the additive model. There were significant increases in the TGFBR1*6A variants in osteosarcoma cases compared to control in all 3 models. Further analysis showed that TGFBR1*6A genotypes were not associated with gender, age, or tumor location. However, TGFBR1*6A was significantly associated with less metastasis. CONCLUSIONS: TGFBR1*6A, a dominant polymorphism of TGFBR1, is associated with increased susceptibility and metastasis spread of osteosarcoma.

Functional and radiological evaluations of unstable displaced proximal humeral fractures treated with closed reduction and percutaneous pinning fixation.

OBJECTIVE: The purpose of this study is to evaluate the functional and radiological outcomes of patients with unstable displaced proximal humeral fractures treated with closed reduction and percutaneous pinning (CRPP) fixation. METHODS: We retrospectively reviewed 87 cases of displaced (2-, 3- or 4-part fractures according to Neer classification) proximal humeral fractures treated with CRPP fixation in our center from September 2003 to September 2008. Sixty-four patients were followed up for a period ranging from 12 to 48 months (averaging 16.2 months) and evaluated for the functional and radiological outcomes by a series of standard questionnaire and measurement. RESULTS: The fractures in all 64 patients were healed with an average time of 15.4 weeks (ranging from 12 to 43 weeks), and the mean interval between the operation and full functional exercise was 17.3 weeks (ranging from 14 to 38 weeks). At the final follow-up visit, no patients showed shoulder instability; the mean range of abduction motion was 157.1° (ranging from 70 to 180°). For all patients, no statistically significant difference in the functional outcomes was observed between their 6-month and final follow-up visits, nor in the radiological findings between their immediately postoperative and fi- nal follow-up examinations. CONCLUSION: CRPP fixation is a feasible treatment option for unstable displaced proximal humeral fractures, especially for 2- and 3-part fractures in elderly patients. Although technically demanding, it offers reliable stability without extensive soft tissue dissection, allowing the early painless range of motion. This technique could also promote bone healing, prevent ischemic osteonecrosis of the head of humerus and lead to few complications.

A caspase-6 and anti-HER2 antibody chimeric tumor-targeted proapoptotic molecule decreased metastasis of human osteosarcoma.

Human growth factor receptor-2 (HER2), overexpressed as a result of gene amplification, is detected in 20-40% of patients with breast, ovarian, endometrial, gastric, bladder, prostate, or lung cancers, correlated to metastasis of many tumors, and considered to be a poor prognostic indicator for these tumors. However, the data was controversial for HER2 overexpression and the prognosis of osteosarcoma, which is the most common primary malignant bone tumor, presents a therapeutic challenge in medical oncology due to its metastasis and poor response to current treatments. Previously, we reported that the immunocasp-6 gene fused by a HER2-specific single-chain antibody with domain II of Pseudomonas exotoxin A (PEA) and the 5' end of the truncated active caspase-6 could selectively suppress the HER2-positive tumor growth. In this study, we extend its application. We first confirmed the higher HER2 expression on the surface of metastatic osteosarcoma SOSP-9607(E10) cells, which then be proved specifically addicted to immunocasp-6-induced cells killing in vitro. Thereafter, the efficacy of immunocasp-6 was tested in an osteosarcoma lung metastasis mouse model using intramuscular (i.m.) injections of liposome-encapsulated vectors. Our results showed that the expression of the immunocasp-6 gene not only significantly prolonged animal's survival, but also greatly inhibited tumor metastasis. Thereby, our strategy suggests an alternative approach to treating HER2/neu-positive osteosarcoma.

Establishment of reproducible osteosarcoma rat model using orthotopic implantation technique.

In experimental musculoskeletal oncology, there remains a need for animal models that can be used to assess the efficacy of new and innovative treatment methodologies for bone tumors. Rat plays a very important role in the bone field especially in the evaluation of metabolic bone diseases. The objective of this study was to develop a rat osteosarcoma model for evaluation of new surgical and molecular methods of treatment for extremity sarcoma. One hundred male SD rats weighing 125.45+/-8.19 g were divided into 5 groups and anesthetized intraperitoneally with 10% chloral hydrate. Orthotopic implantation models of rat osteosarcoma were performed by injecting directly into the SD rat femur with a needle for inoculation with SD tumor cells. In the first step of the experiment, 2x10(5) to 1x10(6) UMR106 cells in 50 microl were injected intraosseously into median or distal part of the femoral shaft and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from ultrasound with findings from necropsia and determining time of survival. In the third stage, the orthotopically implanted tumors and lung nodules were resected entirely, sectioned, and then counter stained with hematoxylin and eosin for histopathologic evaluation. The tumor take rate was 100% for implants with 8x10(5) tumor cells or more, which was much less than the amount required for subcutaneous implantation, with a high lung metastasis rate of 93.0%. Ultrasound and necropsia findings matched closely (r=0.942; p<0.01), which demonstrated that Doppler ultrasonography is a convenient and reliable technique for measuring cancer at any stage. Tumor growth curve showed that orthotopically implanted tumors expanded vigorously with time-lapse, especially in the first 3 weeks. The median time of survival was 38 days and surgical mortality was 0%. The UMR106 cell line has strong carcinogenic capability and high lung metastasis frequency. The present rat osteosarcoma model was shown to be feasible: the take rate was high, surgical mortality was negligible and the procedure was simple to perform and easily reproduced. It may be a useful tool in the investigation of antiangiogenic and anticancer therapeutics. Ultrasound was found to be a highly accurate tool for tumor diagnosis, localization and measurement and may be recommended for monitoring tumor growth in this model.

Functional and radiological evaluations of high-energy tibial plateau fractures treated with double-buttress plate fixation.

OBJECTIVE: This study was designed to evaluate the functional and radiological outcomes of patients with complex tibial plateau fractures treated with double-buttress plate fixation. METHODS: Sixty five cases of complex (Schatzker type V and VI) tibial plateau fractures were treated with double-buttress plate fixation in our centre from September 2001 to September 2006 through two separate plate incisions. Fifty four patients were followed up for a period ranging from 12 to 48 months and evaluated for the functional and radiological outcomes by a series of standard questionnaire and measurement. RESULTS: Due to the good exposure without any extensive soft-tissue dissection of the double-buttress plate fixation, the fractures in all 54 patients were healed and the treatment achieved greater than 90% of satisfactory-to-excellent rates of reduction. The mean time of bone union was 15.4 weeks (range, 12-30 weeks), and the mean time of full weight-bearing was 18.7 weeks (range, 14-26 weeks). At the final follow-up visit, no patients showed knee instability; the mean range of motion was 107.6 degrees (range, 85 degrees -130 degrees ). For all patients, no statistically significant difference in the functional outcomes was observed between their 6-months and final follow-up visits; or in the radiological findings between their immediate postoperative and final follow-up examinations. CONCLUSION: Double-buttress plate fixation is a feasible treatment option for bilcondylar and complex tibial plateau fractures. Although technically demanding, it offers reliable stability without additional postoperative adjuvant external fixation, and at the same time avoids extensive soft tissue dissection, allowing the early painless range of motion.

Single-chain antibody/activated BID chimeric protein effectively suppresses HER2-positive tumor growth.

BH3-interacting domain death agonist (BID) is a crucial element in death signaling pathways and is recognized as an intracellular link connecting the intrinsic mitochondrial apoptotic and extrinsic death receptor-mediated apoptotic pathways. Herein, we describe experiments conducted with a fusion protein, which was generated by fusing a human epidermal growth factor receptor-2 (HER2)-specific single-chain antibody with domain II of Pseudomonas exotoxin A and the truncated active BID (tBID). These experiments extend our previous work on several other immuno-proapoptotic proteins. Specifically, by excluding cells with undetectable HER2, we showed that the secreted immuno-tBID molecule selectively recognized and killed HER2-overexpressing tumor cells in vitro by attacking their mitochondria and inducing their apoptotic death. This apoptosis could only be inhibited partially by caspase pan-inhibitor zVAD and mitochondrial protector TAT-BH4. Subsequently, we transferred the immuno-tbid gene into BALB/c athymic mice bearing HER2-positive tumors together with other immuno-proapoptotic proteins using i.m. injections of liposome-encapsulated vectors. The expression of the immuno-tbid gene suppressed tumor growth and prolonged animal survival significantly. We also shortened the translocation domain of Pseudomonas exotoxin A II to only 10-amino acid sequence, which were crucial for furin cleavage. The new recombinant molecule retained the translocation efficiency and the ability of specific killing HER2-positive tumor cells. Our data showed that, compared with the toxins employed before, the chimeric immuno-tBID molecule can not only specifically recognize HER2-positive tumor cells but also certainly induce apoptosis even in the presence of zVAD and TAT-BH4, thereby suggesting an alternative approach to treating HER2/neu-positive tumors.