Clinical and Radiographic Outcomes of Inversed Restricted Kinematic Alignment Total Knee Arthroplasty by Asia Specific (Huang's) Phenotypes, a Prospective Pilot Study.

Inverse restricted kinematic alignment (irKA) was modified from restricted kinematic alignment for total knee arthroplasty (TKA). This prospective single-center study aimed to evaluate the outcomes of irKA-TKA on all knee subtypes classified by Asia specific (Huang's) phenotypes. A total of 96 knees that underwent irKA-TKA at one hospital between January 2018 and June 2020 were included, with 15 knees classified in Type 1, nine in Type 2, 15 in Type 3, 47 in Type 4, and 10 in Type 5 by Huang's phenotypes. Outcomes were knee alignment measures and patient-reported satisfaction evaluated by the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and traditional Chinese version of the Forgotten Joint Score-12 (FJS-12). Follow-up was one year. Type 4 knee was most significantly corrected in all angles by irKA-TKA, followed by Type 2 and 3 knees. Type 5 and 1 knee were only significantly corrected in some angles. The correlation between FJS-12 and WOMAC was good at 6 months (Pearson correlation coefficient (r) = 0.74) and moderate at 6 weeks, 3 months, and 12 months during follow-up (r = 0.37~0.47). FJS-12 and WOMAC displayed comparable hip-knee-ankle angle cut-off value (4.71° vs. 6.20°), sensitivity (70.49% vs. 67.19%), specificity (84.00% vs. 85.71%), and Youden index (54.49% vs. 52.90%) in prediction of good prognosis. In conclusion, irKA-TKA corrects knee alignment in all knee types with increasing satisfaction for one-year follow-up. Knees with presurgical varus deformity are most recommended for irKA-TKA. Both presurgical scores of the traditional Chinese version of FJS-12 and WOMAC predict the prognosis of irKA-TKA.

The Association between Iron-Deficiency Anemia (IDA) and Septic Arthritis (SA): The Real-World Data.

Background and Objectives: Iron-deficiency anemia (IDA) could predispose the afflicted individuals to various infections and musculoskeletal disorders. This study attempted to investigate the association between IDA and septic arthritis (SA), a musculoskeletal disease. Materials and Methods: We investigated all the eligible subjects in the Taiwanese longitudinal health insurance database (LHID) between 2000 and 2012. Subjects with the diagnosis of IDA (International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM): 280) were allocated to the IDA cohort. The control subjects were randomly matched to every subject with IDA coding by age and sex at the 1:4 ratio. All of the recruited subjects were followed since the index date to the onset of SA (ICD-9-CM: 711.0), withdrawal from the insurance (including death), or 31 December 2013. Results: The cumulative incidence of SA was assessed. We showed that the cumulative incidence of SA was higher in the IDA cohort than in the control cohort (p-value < 0.0001). After adjustment of the comorbidities, the IDA patients had a 2.53-fold risk of SA compared to control subjects (aHR = 2.53, 95% CI = 1.89−3.38). Conclusions: IDA was associated with an increased risk of SA.

Makoplasty medial unicondylar knee replacement: Correction or postoperative angle matters?

INTRODUCTION: Various considerations prevail around optimal postoperative varus deformity, correction angle and physiological constitutional varus deformity. The goal of our present study was to understand correlation between these parameters and their influence over Western Ontario McMaster University Osteoarthritis Index scale (WOMAC). MATERIALS AND METHODS: Consecutive robotic-arm-assisted medial onlay fixed bearing unicompartmental knee arthroplasty (UKA) in 143 knees studied. WOMAC score was recorded preoperatively and at specific intervals after surgery for consecutive 2 years. RESULTS: Mean preoperative and postoperative varus deformities were 10.2° and 4.8°, respectively, and mean correction angle was 5.4°. The preoperative varus and correction angles were found well correlated (r = 0.815). The amount of improvement in the WOMAC total score was not influenced by the postoperative varus angle. CONCLUSION: The correction angle has a stronger correlation with preoperative varus deformity, and postoperative varus deformity does not imply favourable clinical outcomes.

Epidemiology of fatal/non-fatal suicide among patients with chronic osteomyelitis (COM): a nationwide population-based study.

OBJECTIVE: Chronic osteomyelitis (COM) can induce systemic inflammation, and systemic inflammation may be associated with suicide tendency. However, no studies have investigated the correlation between COM and suicide tendency. METHODS: The aim of this population-based study was to determine the epidemiology of fatal/non-fatal suicide among COM patients. Subjects with at least two outpatient visits or one course of inpatient care diagnosed with COM were recruited into a COM cohort. The control/COM subject ratio was approximately 4:1 matched by age, sex, major depression coding and index year (COM patients). Subjects with suicide attempts before COM diagnosis and subjects aged <20 years were excluded. RESULTS: COM patients had 1.93 (95% confidence interval [CI]: 1.11-3.36) times the risk of fatal/non-fatal suicide as control subjects. Considering death as the competing event of fatal/non-fatal suicide, COM patients had 1.76 (95% CI: 1.03-3.01) times the risk of fatal/non-fatal suicide (competing risk regression model). The effect of COM on fatal/non-fatal suicide was more prominent among diabetic patients. COM severity also correlated with the risk of fatal/non-fatal suicide. CONCLUSIONS: More attention must be paid to suicide tendency among COM patients.

A combination of bimalleolar fracture and fracture on talar body and neck: A rare case report.

RATIONALE: Talar fracture accompanied with malleolar fracture is rare, and its management is complex. Ankle soft tissue is much thinner than other parts of the human body, and the shape of the ankle makes wounds difficult to close immediately after surgery, which may result in poor skin condition if the wound tension is too high. However, joint congruity and osteonecrosis are the main concerns of talar fracture. PATIENT CONCERNS: A 57-year-old man presented at the emergency department following a motorcycle accident. DIAGNOSES: Physical examination revealed swelling and tenderness of the left ankle and midfoot. The patient had comminuted talar fracture and was indicated for dual-screw fixation or even plate with screw fixation. INTERVENTIONS: We performed single screw fixation after assessing the soft tissue condition and employed a technique of using continuous longitudinal force to bring together fracture fragments (ankle ligamentotaxis) during surgery. Open reduction with a mini-hook plate and tension band wire was used for bimalleolar fracture repair using the combined anteromedial and anterolateral approach with extension of the incision. Kirschner wire for temporary fixation was performed using ligamentotaxis, and a 2.4 headless screw was inserted from the posteromedial to the anterolateral direction. OUTCOMES: The patient was discharged with a standard short leg splint and was instructed not to bear weight on the affected ankle for 2 months. The patient walked well without discomfort, and the Hawkins sign was clearly visible. Single screw fixation preserves the integrity of the talus bone as minimal space is used for this operative technique. Single screw fixation preserves more bony stock when most of the internal fixator is located within the bone. Additionally, surgery time is shorter than multiple implantations even when performing the same procedure; as a result, there was less ankle soft tissue swelling. LESSONS: This case provides evidence of using the single screw fixation technique for addressing both malleolar and talar fractures, and that talar fracture management can be less aggressive with limited weight bearing and initial limited range of motion given the presence of malleolar fracture. The alignment and stability of bony fragments also benefit from ankle ligamentotaxis.

Improved Bioactivity of 3D Printed Porous Titanium Alloy Scaffold with Chitosan/Magnesium-Calcium Silicate Composite for Orthopaedic Applications.

Recently, cases of bone defects have been increasing incrementally. Thus, repair or replacement of bone defects is gradually becoming a huge problem for orthopaedic surgeons. Three-dimensional (3D) scaffolds have since emerged as a potential candidate for bone replacement, of which titanium (Ti) alloys are one of the most promising candidates among the metal alloys due to their low cytotoxicity and mechanical properties. However, bioactivity remains a problem for metal alloys, which can be enhanced using simple immersion techniques to coat bioactive compounds onto the surface of Ti⁻6Al⁻4V scaffolds. In our study, we fabricated magnesium-calcium silicate (Mg⁻CS) and chitosan (CH) compounds onto Ti⁻6Al⁻4V scaffolds. Characterization of these surface-modified scaffolds involved an assessment of physicochemical properties as well as mechanical testing. Adhesion, proliferation, and growth of human Wharton's Jelly mesenchymal stem cells (WJMSCs) were assessed in vitro. In addition, the cell attachment morphology was examined using scanning electron microscopy to assess adhesion qualities. Osteogenic and mineralization assays were conducted to assess osteogenic expression. In conclusion, the Mg⁻CS/CH coated Ti⁻6Al⁻4V scaffolds were able to exhibit and retain pore sizes and their original morphologies and architectures, which significantly affected subsequent hard tissue regeneration. In addition, the surface was shown to be hydrophilic after modification and showed mechanical strength comparable to natural bone. Not only were our modified scaffolds able to match the mechanical properties of natural bone, it was also found that such modifications enhanced cellular behavior such as adhesion, proliferation, and differentiation, which led to enhanced osteogenesis and mineralization downstream. In vivo results indicated that Mg⁻CS/CH coated Ti⁻6Al⁻4V enhances the bone regeneration and ingrowth at the critical size bone defects of rabbits. These results indicated that the proposed Mg⁻CS/CH coated Ti⁻6Al⁻4V scaffolds exhibited a favorable, inducive micro-environment that could serve as a promising modification for future bone tissue engineering scaffolds.

The Incidence and Risk Factors of Hip Fracture after Liver Transplantation (LT): A Nationwide Population-Based Study.

BACKGROUND: Osteoporosis and fragility fracture are the major complications after liver transplantation (LT). The aim of the study was to determine the incidence and risk factors of hip fracture after LT. METHODS: We conducted a retrospective population-based cohort study, enrolling the patients receiving LT between January 1999 and December 2010. Control subjects were randomly matched to every recipient by age and sex by 1 : 10 ratios. RESULTS: During the follow-up period, 17 recipients (0.77%) and 70 (0.32%) control subjects suffered from hip fractures. The incident rates (per 10000 person-years) were 21.49 for recipients and 7.52 for controls (adjusted hazard ratio = 2.71; 95% confidence interval = 1.21-6.05). The cumulative incidence of hip fracture was significantly higher among the recipients (p < 0.0001). Among the recipients, the subjects aged >65 years at transplantation and with pretransplant steroid use are more susceptible to posttransplant hip fracture. Immunosuppressive agents did not significantly affect the risk of hip fracture among recipients. CONCLUSIONS: Liver transplantation is a risk factor for hip fractures. Aged >65 years at transplantation and pretransplant steroid use are risk factors for posttransplant hip fractures among the recipients.

Correction: Resistin promotes tumor metastasis by down-regulation of miR-519d through the AMPK/p38 signaling pathway in human chondrosarcoma cells.

[This corrects the article DOI: 10.18632/oncotarget.2724.].

Disorder-related risk factors for revision total hip arthroplasty after hip hemiarthroplasty in displaced femoral neck fracture patients: a nationwide population-based cohort study.

BACKGROUND: The choice of primary hip hemiarthroplasty or total hip arthroplasty for displaced femoral neck fracture is still controversial. Revision hip arthroplasty not only increases risk and cost but also could result in worse outcome. Determining the risk factors for revision can help inform medical decision-making and aid in risk stratification of publicly reported outcomes. Therefore, we conducted a nationwide population-based study to identify the disease-related risk factors and construct a risk score nomogram to predict revision surgery. METHODS: Records of all 68,030 femoral neck fracture patients receiving partial hemiarthroplasty (HA) in 2000-2010, with no total hip arthroplasty (THA) or revision HA history, were collected from the National Health Insurance Research Database. Cox proportional hazard regression was used to estimate the risk of revision hip replacement (RHA). The score of each risk factor was the quotient of the regression coefficient of the variable by the regression coefficient for a 10-year increase in age. The predictive accuracy was tested using the area under the receiver operating characteristic curve (AUROC). RESULTS: The revision risk for hemiarthroplasty increased in male, those with schizophrenia and end-stage renal disease patients had 1.58-, 1.88-, and 1.74-fold revision HA risk (95 % confidence interval (CI) = 1.40-1.78, 1.26-2.79, and 1.29-2.34, respectively). In a predictive model, the cumulative risk score ranged from 0 to 13 with a 5.08 to 91.82 % 10-year predicted RHA risk. The percentage of AUROC for 10-year RHA risk in nomogram was 61.9 (95 % CI = 60.0-63.4). CONCLUSIONS: Males, schizophrenia and end-stage renal disease patients have higher risk of revision surgery after hemiarthroplasty for femoral neck fracture.

A Minimally Invasive Endoscopic Surgery for Infectious Spondylodiscitis of the Thoracic and Upper Lumbar Spine in Immunocompromised Patients.

This study evaluates the safety and effectiveness of computed tomography- (CT-) assisted endoscopic surgery in the treatment of infectious spondylodiscitis of the thoracic and upper lumbar spine in immunocompromised patients. From October 2006 to March 2014, a total of 41 patients with infectious spondylodiscitis underwent percutaneous endoscopic surgery under local anesthesia, and 13 lesions from 13 patients on the thoracic or upper lumbar spine were selected for evaluation. A CT-guided catheter was placed before percutaneous endoscopic surgery as a guide to avoid injury to visceral organs, major vessels, and the spinal cord. All 13 patients had quick pain relief after endoscopic surgery without complications. The bacterial culture rate was 77%. Inflammatory parameters returned to normal after adequate antibiotic treatment. Postoperative radiographs showed no significant kyphotic deformity when compared with preoperative films. As of the last follow-up visit, no recurrent infections were noted. Traditional transthoracic or diaphragmatic surgery with or without posterior instrumentation is associated with high rates of morbidity and mortality, especially in elderly patients, patients with multiple comorbidities, or immunocompromised patients. Percutaneous endoscopic surgery assisted by a CT-guided catheter provides a safe and effective alternative treatment for infectious spondylodiscitis of the thoracic and upper lumbar spine.

Clinical outcome and radiographic change of ipsilateral scapular neck and clavicular shaft fracture: comparison of operation and conservative treatment.

OBJECTIVE: The purpose of this study is to compare glenopolar angle (GPA) and the functional outcomes of fixation of both the clavicle and the scapular neck, fixation of the clavicle alone, and conservative treatment for floating-shoulder injuries. METHODS: A prospective stratified randomized study was performed in 39 adult patients who suffered floating-shoulder injuries and underwent fixation of both the clavicle and the scapular neck (group A), or fixation of the clavicle alone (group B), or conservative treatment (group C) between January 2005 and September 2011. The GPA, Disabilities of the Arm, Shoulder and Hand (DASH) score, and Constant-Murley Shoulder Outcome (Constant) score were compared between the three groups. RESULTS: All 39 patients were followed up for more than 2 years. GPA after bony consolidation was significantly better in group A than in groups B and C (p = 0.015). Functional outcomes measured by DASH and Constant scores were significantly better in group A at final follow-up (p = 0.008 and 0.002, respectively). Both DASH and Constant scores were highly correlated with GPA after consolidation (p < 0.001, respectively). The receiver operating characteristic (ROC) analysis showed that of the two randomly selected DASH scores, the smaller DASH score would have a larger GPA than the larger DASH score. Similarly, the larger Constant score would have a larger GPA than the smaller Constant score. CONCLUSIONS: Fixation of both the clavicle and the scapular neck may correct GPA and improve functional outcomes for the treatment of floating-shoulder injuries. GPA after fracture consolidation is a useful prognostic indicator of a satisfactory clinical outcome as defined by either DASH score or Constant score.

Resistin promotes tumor metastasis by down-regulation of miR-519d through the AMPK/p38 signaling pathway in human chondrosarcoma cells.

Resistin is a recently discovered adipocyte-secreting adipokine, which may play a critical role in modulating cancer pathogenesis. Chondrosarcoma is a highly malignant tumor known to frequently metastasize; however, the role of resistin in the metastasis of human chondrosarcoma is largely unknown. Here, we found that the expression of resistin was higher in chondrosarcoma biopsy tissues than in normal cartilage. Moreover, treatment with resistin increased matrix metalloproteinase (MMP)-2 expression and promoted cell migration in human chondrosarcoma cells. Co-transfection with microRNA (miR)-519d mimic resulted in reversed resistin-mediated cell migration and MMP-2 expression. Additionally, AMP-activated protein kinase (AMPK) and p38 inhibitors or siRNAs reduced the resistin-increased cell migration and miR-519d suppression, and inhibition of resistin expression resulted in suppression of MMP-2 expression and lung metastasis in vivo. Taken together, our results indicate that resistin promotes chondrosarcoma metastasis and MMP-2 expression through activation of the AMPK/p38 signaling pathway and down-regulation of miR-519d expression. Therefore, resistin may represent a potential novel molecular therapeutic target in chondrosarcoma metastasis.

Readiness to quit as a predictor for outcomes of smoking-reduction programme with transdermal nicotine patch or bupropion in a sample of 308 patients with schizophrenia.

Readiness to quit has been found to predict smoking-cessation outcomes in a general population. However, little is known about the relationship between the readiness to quit and smoking-reduction outcomes in patients with schizophrenia treated with pharmacological adjuvants. The aim of this study was to examine the association between readiness to quit and smoking-reduction outcomes in patients with schizophrenia. A total of 308 subjects using nicotine replacement therapy (NRT) (N = 242) or bupropion (N = 66) participated in an 8-week smoking-reduction programme. Participants were categorised into precontemplators (N = 127), contemplators (N = 76) and preparators (N = 105) to quit smoking based on the transtheoretical model. There was a significant difference in change in number of cigarettes (NOC) (p = 0.007) and Fagerstrom test for nicotine dependence (FTND) score (nicotine dependence level) (p = 0.029) across the stages of change. A linear regression model revealed trend of increasing reduction in NOC and FTND scores in different stages of change (NOC: B = -1.22, t = -2.81, p = 0.005; FTND: B = -0.43, t = -2.57, p = 0.011). However, the 7-day point prevalence of abstinence was 5.5% (18/308), but there was no significant association between stage of change and smoking cessation (p = 0.26), possibly due to a very small sample size of successful quitters. In summary, among a cohort of institutionalised chronic schizophrenia patients receiving 8-week NRT or bupropion, stage of change can predict smoking reduction and may serve as a useful indicator for patients' preparedness before a trial of smoking reduction.

Fracture as an independent risk factor of dementia: a nationwide population-based cohort study.

Dementia is among various diseases affecting the elderly, who is also at a high risk for fractures. This study aimed to evaluate the association between fracture history and sequential risk of dementia in Taiwan.A retrospective cohort study was designed using the claims data of the entire insured residents covered by Taiwan's universal health insurance from 1998 to 2010. A total of 66,797 patients with fractures and 133,594 control subjects without fractures were matched in terms of age (±5 years), sex, and index year and then recruited. Fractures and dementia were defined in accordance with the International Classification of Diseases, 9th Revision, Clinical Modification. The influence of fractures on the risk of dementia was analyzed using a Cox proportional hazards model.After a 12-year follow-up period, 2775 and 3991 incident cases of dementia were reported in exposed and unexposed cohorts, respectively. The overall incidence rate of dementia in individuals with fractures was 41% higher than that in individuals without fractures (6.05 vs 4.30 per 1000 person-years) at an adjusted hazard ratio of 1.38 (95% confidence interval 1.32-1.45) after age, sex, urbanization, and individual disorders or comorbidities were adjusted. Considering fracture location, we found that patients with hip fractures were at a slightly high risk for dementia. The occurrence of multiple fractures at a single visit was also significantly associated with an increased risk of dementia.Fracture history is regarded as an independent risk factor of dementia in individuals aged ≥65 years, particularly those who suffered from multiple fractures and/or fractures located in the hip. Further studies are needed to support an independent role of fracture in dementia considering the clinical information and other comorbidities.

Cloning, overexpression, purification and crystallization of malate dehydrogenase from Thermus thermophilus.

Malate dehydrogenase (MDH) has been used as a conjugate for enzyme immunoassay of a wide variety of compounds, such as drugs of abuse, drugs used in repetitive therapeutic application and hormones. In consideration of the various biotechnological applications of MDH, investigations of MDH from Thermus thermophilus were carried out to further understand the properties of this enzyme. The DNA fragment containing the open reading frame of mdh was amplified from the genomic DNA of T. thermophilus and cloned into the expression vector pET21b(+). The protein was expressed in a soluble form in Escherichia coli strain BL21(DE3). Homogeneous protein was obtained using a three-step procedure consisting of thermal treatment, Ni(2+)-chelating chromatography and size-exclusion chromatography. The purified MDH was crystallized and the crystals diffracted to a resolution of 1.80 Šon the BL13C1 beamline of the National Synchrotron Radiation Research Center (NSRRC), Taiwan. The crystals belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 71.3, b = 86.1, c = 118.2 Å. The unit-cell volume of the crystal is compatible with the presence of two monomers in the asymmetric unit, with a corresponding Matthews coefficient VM of 2.52 Å(3) Da(-1) and a solvent content of 51.2%. The crystal structure of MDH has been solved by molecular replacement and is currently under refinement.

Crystal structures and molecular dynamics simulations of thermophilic malate dehydrogenase reveal critical loop motion for co-substrate binding.

Malate dehydrogenase (MDH) catalyzes the conversion of oxaloacetate and malate by using the NAD/NADH coenzyme system. The system is used as a conjugate for enzyme immunoassays of a wide variety of compounds, such as illegal drugs, drugs used in therapeutic applications and hormones. We elucidated the biochemical and structural features of MDH from Thermus thermophilus (TtMDH) for use in various biotechnological applications. The biochemical characterization of recombinant TtMDH revealed greatly increased activity above 60 °C and specific activity of about 2,600 U/mg with optimal temperature of 90 °C. Analysis of crystal structures of apo and NAD-bound forms of TtMDH revealed a slight movement of the binding loop and few structural elements around the co-substrate binding packet in the presence of NAD. The overall structures did not change much and retained all related positions, which agrees with the CD analyses. Further molecular dynamics (MD) simulation at higher temperatures were used to reconstruct structures from the crystal structure of TtMDH. Interestingly, at the simulated structure of 353 K, a large change occurred around the active site such that with increasing temperature, a mobile loop was closed to co-substrate binding region. From biochemical characterization, structural comparison and MD simulations, the thermal-induced conformational change of the co-substrate binding loop of TtMDH may contribute to the essential movement of the enzyme for admitting NAD and may benefit the enzyme's activity.

Clinical practice and evaluation of electronic portal imaging device for VMAT quality assurance.

Volumetric-modulated arc therapy (VMAT) is a novel extension of the intensity-modulated radiation therapy (IMRT) technique, which has brought challenges to dose verification. To perform VMAT pretreatment quality assurance, an electronic portal imaging device (EPID) can be applied. This study's aim was to evaluate EPID performance for VMAT dose verification. First, dosimetric characteristics of EPID were investigated. Then 10 selected VMAT dose plans were measured by EPID with the rotational method. The overall variation of EPID dosimetric characteristics was within 1.4% for VMAT. The film system serving as a conventional tool for verification showed good agreement both with EPID measurements ([94.1 ± 1.5]% with 3 mm/3% criteria) and treatment planning system (TPS) calculations ([97.4 ± 2.8]% with 3 mm/3% criteria). In addition, EPID measurements for VMAT presented good agreement with TPS calculations ([99.1 ± 0.6]% with 3 mm/3% criteria). The EPID system performed the robustness of potential error findings in TPS calculations and the delivery system. This study demonstrated that an EPID system can be used as a reliable and efficient quality assurance tool for VMAT dose verification.

Primary traumatic patellar dislocation.

Acute traumatic patellar dislocation is a common injury in the active and young adult populations. MRI of the knee is recommended in all patients who present with acute patellar dislocation. Numerous operative and non-operative methods have been described to treat the injuries; however, the ideal management of the acute traumatic patellar dislocation in young adults is still in debate. This article is intended to review the studies to the subjects of epidemiology, initial examination and management.

Anti-interleukin-6 receptor antibody inhibits the progression in human colon carcinoma cells.

BACKGROUND: Interleukin-6 (IL-6) promotes proliferation and invasion in colorectal carcinoma, and serum IL-6 levels are correlated with survival in patients with colorectal carcinoma. In this study, we attempted to clarify the signal pathway downstream of IL-6 and the role of the IL-6 receptor complex in terms of the biological effects of clonogenic growth and invasiveness in colorectal carcinoma cells. MATERIALS AND METHODS: IL-6-stimulated SW480 cells were treated with IL-6 receptor neutralization antibody, mitogen-activated protein kinase (MAPK) inhibitor and phosphatidylinositol 3-kinase inhibitor, and clonogenic growth and invasiveness were assessed. IL-6 and IL-6 receptor-expressing LoVo cells were also tested the IL-6 receptor antibody effect. The downstream molecules of the IL-6-mediated pathway were also evaluated. RESULTS: IL-6 effectively enhanced the clonogenicity and invasiveness of SW480; however, these abilities were reversed by treatment with anti-IL-6 receptor antibody, and MAPK and PI3K inhibitors exhibited partial ability to reduce these effects. Similar effects were also found in anti-IL-6 receptor antibody-treated LoVo cells in addition of modulating STAT3 pathway. Anti-IL-6 receptor antibody also inhibited matrix metalloproteinase-2 (MMP-2) and 9 (MMP-9) expressions in IL-6-stimulated SW480. CONCLUSIONS: IL-6 and the IL-6R complex could induce clonogenic growth and invasiveness by mediating signals in the Ras/MAPK and PI3K/AKt pathways, and the malignant phenotypes might be associated with the production of MMP-2 and MMP-9 after IL-6 stimulation in SW480 cancer cells.

Evidence that highly conserved residues of Delonix regia trypsin inhibitor are important for activity.

Delonix regia trypsin inhibitor (DrTI) consists of a single-polypeptide chain with a molecular mass of 22 kDa and containing two disulfide bonds (Cys44-Cys89 and Cys139-Cys149). Sequence comparison with other plant trypsin inhibitors of the Kunitz family reveals that DrTI contains a negatively charged residue (Glu68) at the reactive site rather than the conserved Arg or Lys found in other Kunitz-type trypsin inhibitors. Site-directed mutagenesis yielded five mutants containing substitutions at the reactive site and at one of the disulfide bonds. Assay of the recombinant proteins showed mutant Glu68Leu and Glu68Lys to have only 4-5% of the wild-type activity. These provide evidence that the Glu68 residue is the reactive site for DrTI and various other Kunitz-type trypsin inhibitors. The Cys139Gly mutant lost its inhibitory activity, whereas the Cys44Gly mutant did not, indicating that the second disulfide bond (Cys139-Cys149) is critical to DrTI inhibitory activity, while the first disulfide bond (Cys44-Cys89) is not required.