Lymphocyte transformation test reveals low prevalence of true metal hypersensitivity among pre-operative total knee arthroplasty patients.

PURPOSE: The aims of this study were to determine the prevalence of metal hypersensitivity, and identify pre-operative factors which could predict susceptibility to hypersensitivity reactions among patients scheduled for primary total knee arthroplasty (TKA). The present study used a testing method consistent with the recognised biological response to metals. METHODS: A prospective cross-sectional analysis of 220 patients was conducted. All patients received a testing protocol using lymphocyte transformation test to evaluate reactivity to possible contents of orthopaedic implants. Test response is interpreted as stimulation index (SI) values. A comprehensive questionnaire was used to evaluate prior exposure. Patients were categorised according to SI values and the odds ratios (OR) were calculated as comparative effect measure for each predetermined prior exposure factor. RESULTS: The prevalence of metal sensitivity response was 28% (n = 61) among patients with susceptibility to at least one agent (SI = 2 to 4.9), and 3.2% (n = 7) among patients with true hypersensitivity (SI ≥ 5). The population-weighted prevalence, adjusted for sampling weights of symptomatic knee osteoarthritis, was SI ≥ 5 = 4.7% (95% CI 0.4-11.8%) and SI ≥ 2 = 35.2% (95% CI 24.8-48.6%). Stimulation index levels of response to materials were markedly varied with the highest being aluminium. Female sex, smoking history, cutaneous reaction to jewellery, occupational exposure, and dental procedures were among factors shown to increase the odds of having higher reactivity response to tested metals. Nevertheless, patients with well-functioning prior contralateral TKA did not appear at greater risk of having either sensitivity or susceptibility with odds ratio (OR) = 0.2 (95% CI 0.01-3.2), p: NS and OR = 0.6 (95% CI 0.3-1.2), p: NS, respectively. Prior positive patch test was neither predictor of susceptibility to hypersensitivity OR = 1.2 (95% CI 0.6-2.6) p: NS nor predictor of true hypersensitivity OR = 0.7 (95% CI 0.08-6.1), p: NS. CONCLUSION: Among patients scheduled for primary TKA with no prior clinical features of metal allergy the prevalence of true hypersensitivity to at least one metal is just over 3%. Patients are likely to encounter a material to which they have pre-existing susceptibility to hypersensitivity. With certain prior exposure factors, there was increased susceptibility to metal hypersensitivity reaction evoking an acquired condition. LEVEL OF EVIDENCE: Level II, prospective cross-sectional study.

Elucidating the Role of Protandim and 6-Gingerol in Protection Against Osteoarthritis.

Protandim and 6-gingerol, two potent nutraceuticals, have been shown to decrease free radicals production through enhancing endogenous antioxidant enzymes. In this study, we evaluated the effects of these products on the expression of different factors involved in osteoarthritis (OA) process. Human OA chondrocytes were treated with 1 ng/ml IL-1ß in the presence or absence of protandim (0-10 µg/ml) or 6-gingerol (0-10 µM). OA was induced surgically in mice by destabilization of the medial meniscus (DMM). The animals were treated weekly with an intraarticular injection of 10 µl of vehicle or protandim (10 µg/ml) for 8 weeks. Sham-operated mice served as controls. In vitro, we demonstrated that protandim and 6-gingerol preserve cell viability and mitochondrial metabolism and prevented 4-hydroxynonenal (HNE)-induced cell mortality. They activated Nrf2 transcription factor, abolished IL-1ß-induced NO, PGE2 , MMP-13, and HNE production as well as IL-ß-induced GSTA4-4 down-regulation. Nrf2 overexpression reduced IL-1ß-induced HNE and MMP-13 as well as IL-1ß-induced GSTA4-4 down-regulation. Nrf2 knockdown following siRNA transfection abolished protandim protection against oxidative stress and catabolism. The activation of MAPK and NF-κB by IL-1ß was not affected by 6-gingerol. In vivo, we observed that Nrf2 and GSTA4-4 expression was significantly lower in OA cartilage from humans and mice compared to normal controls. Interestingly, protandim administration reduced OA score in DMM mice. Altogether, our data indicate that protandim and 6-gingerol are essential in preserving cartilage and abolishing a number of factors known to be involved in OA pathogenesis. J. Cell. Biochem. 118: 1003-1013, 2017. © 2016 Wiley Periodicals, Inc.

An overview of the role of lipid peroxidation-derived 4-hydroxynonenal in osteoarthritis.

BACKGROUND: Over the years, many theories have been proposed and examined to better explain the etiology and development of osteoarthritis (OA). The characteristics of joint destruction are one of the most important aspects in disease progression. Therefore, investigating different factors and signaling pathways involved in the alteration of extracellular matrix (ECM) turnover, and the subsequent catabolic damage to cartilage holds chief importance in understanding OA development. Among these factors, reactive oxygen species (ROS) have been at the forefront of the physiological and pathophysiological OA investigation. FINDINGS: In the last decades, research studies provided an enormous volume of data supporting the involvement of ROS in OA. Most interestingly, published data regarding the effect of exogenous antioxidant therapy in OA lack conclusive results from clinical trials to back up in vitro data. Accordingly, it is rational to suggest that there are other reactive species in OA that are not taken into account. Thus, our present review is focused on our current understanding of the involvement of lipid peroxidation-derived 4-hydroxynonenal (HNE) in OA. CONCLUSION: Our findings, like those in the literature, illustrate the central role played by HNE in the regulation of a number of factors involved in joint homeostasis. HNE could thus be considered as an attractive therapeutic target in OA.

Periprosthetic fractures of the acetabulum during cup insertion: posterior column stability is crucial.

Periprosthetic hip fractures around acetabular components are rare with little information available to guide surgical management of these complex injuries. A retrospective review of intraoperative isolated acetabular periprosthetic fractures from three tertiary surgical units was done. A total of 32 patients were identified with 9 initially missed. Acetabular components were stable (type 1) in 11 patients with no failures; unstable (type 2) in 12 patients and treated with supplemental fixation. Non-union and displacement were correlated with absent posterior column plating. Missed fractures (type 3) had the highest reoperation rate. Anterior patterns all healed, whereas fractures with posterior column instability had a 67% failure rate. Periprosthetic acetabular fracture can heal successfully with posterior column stability. Plating is mandatory for large posterior wall fragments to achieve osteointegration.

Sorbitol-modified hyaluronic acid reduces oxidative stress, apoptosis and mediators of inflammation and catabolism in human osteoarthritic chondrocytes.

OBJECTIVE AND DESIGN: Our study was designed to elucidate the precise molecular mechanisms by which sorbitol-modified hyaluronic acid (HA/sorbitol) exerts beneficial effects in osteoarthritis (OA). METHODS: Human OA chondrocytes were treated with increasing doses of HA/sorbitol ± anti-CD44 antibody or with sorbitol alone and thereafter with or without interleukin-1beta (IL-1ß) or hydrogen peroxide (H2O2). Signal transduction pathways and parameters related to oxidative stress, apoptosis, inflammation, and catabolism were investigated. RESULTS: HA/sorbitol prevented IL-1ß-induced oxidative stress, as measured by reactive oxygen species, p47-NADPH oxidase phosphorylation, 4-hydroxynonenal (HNE) production and HNE-metabolizing glutathione-S-transferase A4-4 expression. Moreover, HA/sorbitol stifled IL-1ß-induced metalloproteinase-13, nitric oxide (NO) and prostaglandin E2 release as well as inducible NO synthase expression. Study of the apoptosis process revealed that this gel significantly attenuated cell death, caspase-3 activation and DNA fragmentation elicited by exposure to a cytotoxic H2O2 dose. Examination of signaling pathway components disclosed that HA/sorbitol prevented IL-1ß-induced p38 mitogen-activated protein kinase and nuclear factor-kappa B activation, but not that of extracellular signal-regulated kinases 1 and 2. Interestingly, the antioxidant as well as the anti-inflammatory and anti-catabolic effects of HA/sorbitol were attributed to sorbitol and HA, respectively. CONCLUSIONS: Altogether, our findings support a beneficial effect of HA/sorbitol in OA through the restoration of redox status and reduction of apoptosis, inflammation and catabolism involved in cartilage damage.

Validation of an advanced practice physiotherapy model of care in an orthopaedic outpatient clinic.

BACKGROUND: In Canada, new models of orthopaedic care involving advanced practice physiotherapists (APP) are being implemented. In these new models, aimed at improving the efficiency of care for patients with musculoskeletal disorders, APPs diagnose, triage and conservatively treat patients. Formal validation of the efficiency and appropriateness of these emerging models is scarce. The purpose of this study is to assess the diagnostic agreement of an APP compared to orthopaedic surgeons as well as to assess treatment concordance, healthcare resource use, and patient satisfaction in this new model. METHODS: 120 patients presenting for an initial consult for hip or knee complaints in an outpatient orthopaedic hospital clinic in Montreal, Canada, were independently assessed by an APP and by one of three participating orthopaedic surgeons. Each health care provider independently diagnosed the patients and provided triage recommendations (conservative or surgical management). Proportion of raw agreement and Cohen's kappa were used to assess inter-rater agreement for diagnosis, triage, treatment recommendations and imaging tests ordered. Chi-Square tests were done in order to compare the type of conservative treatment recommendations made by the APP and the surgeons and Student t-tests to compare patient satisfaction between the two types of care. RESULTS: The majority of patients assessed were female (54%), mean age was 54.1 years and 91% consulted for a knee complaint. The raw agreement proportion for diagnosis was 88% and diagnostic inter-rater agreement was very high (κ=0.86; 95% CI: 0.80-0.93). The triage recommendations (conservative or surgical management) raw agreement proportion was found to be 88% and inter-rater agreement for triage recommendation was high (κ=0.77; 95% CI: 0.65-0.88). No differences were found between providers with respect to imaging tests ordered (p≥0.05). In terms of conservative treatment recommendations made, the APP gave significantly more education and prescribed more NSAIDs, joint injections, exercises and supervised physiotherapy (p<0.05). Patient satisfaction was significantly higher for APP care than for the surgeons care (p<0.05). CONCLUSION: The diagnoses and triage recommendations for patients with hip and knee disorders made by the APP were similar to the orthopaedic surgeons. These results provide evidence supporting the APP model for orthopaedic care.

Inhibition of inducible nitric oxide synthase prevents lipid peroxidation in osteoarthritic chondrocytes.

Nitric oxide (NO) and the lipid peroxidation (LPO) product 4-hydroxynonenal (HNE) are considered to be key mediators of cartilage destruction in osteoarthritis (OA). NO is also known to be an important intermediary in LPO initiation through peroxynitrite formation. The aim of the present study was to assess the ability of the inducible NO synthase (iNOS) inhibitor N-iminoethyl-L-lysine (L-NIL) to prevent HNE generation via NO suppression in human OA chondrocytes and cartilage explants. Human OA chondrocytes and cartilage explants were treated with L-NIL and thereafter with or without interleukin-1beta (IL-1ß) or HNE at cytotoxic or non-cytotoxic concentrations. Parameters related to oxidative stress, apoptosis, inflammation, and catabolism were investigated. L-NIL stifled IL-1ß-induced NO release, iNOS activity, nitrated proteins, and HNE generation in a dose-dependent manner. It also blocked IL-1ß-induced inactivation of the HNE-metabolizing glutathione-s-transferase (GST). L-NIL restored both HNE and GSTA4-4 levels in OA cartilage explants. Interestingly, it also abolished IL-1ß-evoked reactive oxygen species (ROS) generation and p47 NADPH oxidase activation. Furthermore, L-NIL significantly attenuated cell death and markers of apoptosis elicited by exposure to a cytotoxic dose of HNE as well as the release of prostaglandin E(2) and metalloproteinase-13 induced by a non-cytotoxic dose of HNE. Altogether, our findings support a beneficial effect of L-NIL in OA by (i) preventing the LPO process and ROS production via NO-dependent and/or independent mechanisms and (ii) attenuating HNE-induced cell death and different mediators of cartilage damage.

Chitosan-Based Nanogels: Synthesis and Toxicity Profile for Drug Delivery to Articular Joints.

One important challenge in treating avascular-degraded cartilage is the development of new drugs for both pain management and joint preservation. Considerable efforts have been invested in developing nanosystems using biomaterials, such as chitosan, a widely used natural polymer exhibiting numerous advantages, i.e., non-toxic, biocompatible and biodegradable. However, even if chitosan is generally recognized as safe, the safety and biocompatibility of such nanomaterials must be addressed because of potential for greater interactions between nanomaterials and biological systems. Here, we developed chitosan-based nanogels as drug-delivery platforms and established an initial biological risk assessment for osteocartilaginous applications. We investigated the influence of synthesis parameters on the physicochemical characteristics of the resulting nanogels and their potential impact on the biocompatibility on all types of human osteocartilaginous cells. Monodisperse nanogels were synthesized with sizes ranging from 268 to 382 nm according to the acidic solution used (i.e., either citric or acetic acid) with overall positive charge surface. Our results demonstrated that purified chitosan-based nanogels neither affected cell proliferation nor induced nitric oxide production in vitro. However, nanogels were moderately genotoxic in a dose-dependent manner but did not significantly induce acute embryotoxicity in zebrafish embryos, up to 100 µg∙mL-1. These encouraging results hold great promise for the intra-articular delivery of drugs or diagnostic agents for joint pathologies.

Nuclear receptor retinoid-related orphan receptor α1 modulates the metabolic activity of human osteoblasts.

Nuclear receptor retinoid-related orphan receptor alpha (RORα1) is a member of ROR-family receptors. It is broadly expressed in various tissues and organs during embryonic development. However, so far, little is known about its function in bone. Here, we have elucidated the expression and function of RORα1 in human MG-63 osteoblast-like cells. Reverse transcriptase-polymerase chain reaction and immunocytochemical analysis revealed that human MG-63 osteoblasts expressed and produced RORα1. Other cell lines, such as THP-1 monocytes expressed also RORα1. RORα1 over-expression increased alkaline phosphatase, osteocalcin, cell mineralization, and collagen type I mRNA and protein expression, while RORα1 RNA silencing inhibited these responses. In addition, RORα1 over-expression suppressed the tumor necrosis factor-alpha (TNFα)-induced production of cyclooxygenase-2, prostaglandin E(2) , and metalloproteinase-9. Examination of the signaling pathways disclosed that RORα1 was able to block TNFα-evoked nuclear factor-kappaB activation. In conclusion, this study demonstrates that RORα1 is involved in human osteoblast metabolism by stimulating osteoblast marker expression and inhibiting inflammatory responses. The results may encourage further exploration of RORα1 as a potential target for the treatment of bone disorders related to inflammation.

Elucidation of molecular mechanisms underlying the protective effects of thymoquinone against rheumatoid arthritis.

Thymoquinone (TQ) is the major active compound derived from the medicinal Nigella sativa. A few studies have shown that TQ exhibits anti-inflammatory activities in experimental models of rheumatoid arthritis (RA) through mechanisms that are not fully understood. The aim of this work was to evaluate the in vitro and in vivo effects of TQ and to investigate its influence on the major signalling pathways involved in pathophysiological RA changes. We used isolated human RA fibroblast-like synoviocytes (FLS) and a rat adjuvant-induced arthritis model of RA. In isolated RA FLS, TQ (0-10 µM) was not cytotoxic and inhibited slightly lipopolysaccharide (LPS)-induced FLS proliferation and strongly H(2)O(2)-induced 4-hydroxynonenal (HNE) generation. By studying different inflammatory and catabolic factors, we determined that TQ significantly abolished LPS-induced interleukin-1beta (IL-1ß), tumour necrosis factor-alpha (TNFα), metalloproteinase-13, cyclooxygenase-2, and prostaglandin E(2). Furthermore, LPS-induced the phosphorylation of p38 mitogen-activated protein kinase, extracellular-regulated kinases ½, and nuclear factor-kappaB-p65 were also blocked by TQ in time-dependent manner. In our experimental RA model, the oral administration of TQ 5 mg/kg/day significantly reduced the serum levels of HNE, IL-1ß and TNFα as well as bone turnover markers, such as alkaline phosphatase and tartrate-resistant acid phosphatase. The protective effects of TQ against RA were also evident from the decrease in arthritis scoring and bone resorption. In conclusion, the fact that TQ abolishes a number of factors known to be involved in RA pathogenesis renders it a clinically valuable agent in the prevention of articular diseases, including RA.

Hydrodynamic delivery of chitosan-folate-DNA nanoparticles in rats with adjuvant-induced arthritis.

50 kDa chitosan was conjugated with folate, a specific tissue-targeting ligand. Nanoparticles such as chitosan-DNA and folate-chitosan-DNA were prepared by coacervation process. The hydrodynamic intravenous injection of nanoparticles was performed in the right posterior paw in normal and arthritic rats. Our results demonstrated that the fluorescence intensity of DsRed detected was 5 to 12 times more in the right soleus muscle and in the right gastro muscle than other tissue sections. ß-galactosidase gene expression with X-gal substrate and folate-chitosan-plasmid nanoparticles showed best coloration in the soleus muscle. Treated arthritic animals also showed a significant decrease in paw swelling and IL-1ß and PGE2 concentration in serum compared to untreated rats. This study demonstrated that a nonviral gene therapeutic approach using hydrodynamic delivery could help transfect more efficiently folate-chitosan-DNA nanoparticles in vitro/in vivo and could decrease inflammation in arthritic rats.

Trajectories of Follow-up Compliance in a Fracture Liaison Service and Their Predictors: A Longitudinal Group-Based Trajectory Analysis.

INTRODUCTION/OBJECTIVES: Identification of groups of patients following similar trajectories of time-varying patient characteristics are often of considerable clinical value. This study provides an example of how the identification of trajectory groups of patients can be useful. METHODS: Using clinical and administrative data of a prospective cohort study aiming to improve the secondary prevention of osteoporosis-related fractures with a Fracture Liaison Service (FLS), trajectory groups for visit compliance over time (2-year follow-up) were predicted using group-based trajectory modeling. Predictors of trajectory groups were identified using multinomial logistic regressions. RESULTS: Among 532 participants (86% women, mean age 63 years), three trajectories were identified and interpreted as high followers, intermediate followers, and low followers. The predicted probability for group-membership was: 48.4% high followers, 28.1% intermediate followers, 23.5% low followers. A lower femoral bone mineral density and polypharmacy were predictors of being in the high followers compared to the low followers group; predictors for being in the intermediate followers group were polypharmacy and referral to a bone specialist at baseline. CONCLUSIONS: Results provided information on visit compliance patterns and predictors for the patients undergoing the intervention. This information has important implications when implementing such health services and determining their effectiveness.

Patient Healthcare Trajectory and its Impact on the Cost-Effectiveness of Fracture Liaison Services.

This study aimed to assess the cost-utility of a Fracture Liaison Service (FLS) with a systematic follow-up according to patients' follow-up compliance trajectories. The Lucky Bone™ FLS is a prospective cohort study conducted on women and men (≥40 years) with fragility fractures. Dedicated personnel of the program identified fractures, investigated, treated, and followed patients systematically over 2 years. Groups of follow-up compliance trajectories were identified, and Markov decision models were used to assess the cost-utility of each follow-up trajectory group compared to usual care. A lifetime horizon from the perspective of the healthcare payer was modeled. Costs were converted to 2018 Canadian dollars and incremental cost-utility ratios (ICURs) were measured. Costs and benefits were discounted at 1.5%. A total of 532 participants were followed in the FLS (86% women, mean age of 63 years). Three trajectories were predicted and interpreted; the high followers (HFs, 48.4%), intermediate followers (IFs, 28.1%), and low followers (LFs, 23.5%). The costs of the interventions per patient varied between $300 and $446 for 2 years, according to the follow-up trajectory. The FLS had higher investigation, treatment, and persistence rates compared to usual care. Compared to usual care, the ICURs for the HF, IF, and LF trajectory groups were $4250, $21,900, and $72,800 per quality-adjusted life year (QALY) gained, respectively ($9000 per QALY gained for the overall FLS). Sensitivity analyses showed that the HF and IF trajectory groups, as well as the entire FLS, were cost-effective in >67% of simulations with respect to usual care. In summary, these results suggest that a high-intensity FLS with a systematic 2-year follow-up can be cost-effective, especially when patients attend follow-up visits. They also highlight the importance of understanding the behaviors and factors that surround follow-up compliance over time as secondary prevention means that they are at high risk of re-fracture. © 2020 American Society for Bone and Mineral Research (ASBMR).

Performance of a Fracture Liaison Service in an Orthopaedic Setting: A Report of Key Indicators and Improvement of Longitudinal Outcomes.

BACKGROUND: Many Fracture Liaison Services (FLSs) have been successfully implemented, but very few incorporate systematic longitudinal follow-up. The objective of this study was to report on the performance of such an FLS using key performance indicators and longitudinal clinical outcomes. METHODS: An FLS was implemented in 2 outpatient orthopaedic clinics. Men and women who were ≥40 years of age and had a recent fragility fracture were recruited. Participants were evaluated, treated when appropriate, and systematically followed over a 2-year period. Clinical data including chart review and questionnaires were collected. Medical services and hospitalization claims data were retrieved from administrative databases. The primary outcomes were the following key performance indicators: the numbers of investigated and treated patients, follow-up attendance, and the incidence of subsequent fractures. Secondary outcomes were the changes in bone turnover markers and quality of life, physical capacity, and pain scores between baseline and follow-up visits. RESULTS: A total of 532 subjects with a mean age of 63.4 years were recruited; 85.7% were female. Bone mineral density results were collected for 472 subjects (88.7%) and a prescription for anti-osteoporosis medication was given to 86.6% of patients. Overall, 83.6% of patients attended at least 1 follow-up visit. The subsequent fracture incidence rate was 2.6 per 100 person-years (23 fractures). The mean level of type-I collagen C-telopeptide (CTX-1), a bone resorption marker, decreased >35%. Clinically important improvements of functional capacity scores (by 14.4% to 63.7%) and pain level (by 19.3% to 35.7%) were observed over time; however, the increase in quality-of-life scores was not clinically important (by 3% to 15.2%). CONCLUSIONS: In this FLS, the rates of investigation, treatment, and participation were >80% over a 2-year period. The subsequent fragility fracture incidence rate was <3 per 100 person-years. These results suggest that an intensive FLS model of care, with a systematic longitudinal follow-up, is effective. A randomized controlled trial is needed to support these results. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Bone-protective effects of nonviral gene therapy with folate-chitosan DNA nanoparticle containing interleukin-1 receptor antagonist gene in rats with adjuvant-induced arthritis.

Interleukin-1 receptor antagonist (IL-1Ra), is a natural blocker of the inflammatory cytokine interleukin-1. Using a rat adjuvant-induced arthritis (AIA) model of rheumatoid arthritis (RA), we examined the protective effects of IL-1Ra in bone metabolism in vivo after folate-mediated nonviral gene delivery. We detected secreted human IL-1Ra protein in serum and cultured primary osteoblasts of rats that were treated with chitosan-IL-1Ra and folate-IL-1Ra-chitosan nanoparticles, respectively. In vivo, IL-1Ra gene delivery significantly reverted alterations in bone turnover observed in arthritic animals by modulating the level of osteocalcin (OC) as well as the activities of alkaline phosphatase and tartrate-resistant acid phosphatase. The protective effects of these nanoparticles were evident from the decrease in the expression levels of interleukine-1beta and prostaglandin E(2) as well as osteoclast number and other histopathological findings. Compared to naked DNA and chitosan-DNA, folate-chitosan-DNA nanoparticles were less cytotoxic and enhanced IL-1Ra protein synthesis in vitro and offered a better protection against inflammation and abnormal bone metabolism in vivo. Nonviral gene therapy with folate-chitosan-DNA nanoparticles containing the IL-1 Ra gene seemed to protect against bone damage and inflammation in rat adjuvant-induced arthritis model.

Persistence and compliance to osteoporosis therapy in a fracture liaison service: a prospective cohort study.

Persistence and compliance to osteoporosis medications aiming to prevent fragility fractures are essential for fracture prevention, but are suboptimal in the population. A Fracture Liaison Service with a systematic follow-up led to ongoing therapy and optimal drug compliance for more than half of treated patients over 2 years. PURPOSE: Fracture Liaison Services (FLS) have the potential to improve persistence and compliance to osteoporosis therapy. We aimed to assess patterns of drug use in a high-level intervention FLS. METHODS: Women and men (> 40 years) with a fragility fracture were recruited in a FLS, where osteoporosis therapy was prescribed if appropriate. Based on claims data, patients who filled their prescription in the 3-month period following baseline were selected. The 1- and 2-year persistence rates were measured using survival analysis. In non-persistent subjects, 1-year treatment re-initiation was measured. The 1- and 2-year compliance levels were measured, using the proportion of days covered (PDC > 80% = compliant). Regression analyses were performed to identify predictors of non-persistence/compliance. RESULTS: Out of 332 subjects with complete drug insurance coverage, 297 (89.5%) were prescribed osteoporosis therapy by the FLS, and 275 (92.6%) were dispensed. Two hundred sixty participants (86.9% female; mean age 65.6 years) were selected for having filled a prescription inside 3 months after baseline. The 1- and 2-year persistence rates were 66.4% and 55.6%, respectively. Treatment re-initiation was observed in 56% of non-persistent patients. PDC was > 80% in 64.2% for 1 year and 62.5% for 2 years. Older and younger age, smoking, higher spine bone mineral density, lower major FRAX risk, and missing follow-up visits were predictors of non-persistence and/or non-compliance. CONCLUSIONS: After 2 years in a high-level intervention FLS, more than half the treated participants were persistent and compliant to treatment. Comparative effectiveness studies must be undertaken to determine whether this intervention is an improvement over usual care.

Rationale, study design, and descriptive data of the Lucky Bone™ Fracture Liaison Service.

The study design of a multidisciplinary Fracture Liaison Service (2-year follow-up) aiming to optimize fragility fracture management in an outpatient setting is presented. Patient characteristics, investigation, and treatment initiation data at baseline were recorded. Results corroborate the care gap in osteoporosis management, reinforcing the need for secondary fracture prevention programs. PURPOSE: This paper describes the study design, implementation, and baseline characteristics of a multidisciplinary Fracture Liaison Service (FLS) in Quebec (Canada). METHODS: A FLS was implemented as a prospective cohort study. After identification, fracture risk was assessed and patients were started on treatment or referred, according to guidelines and risk assessment. Thereafter, patients were systematically followed over 2 years. Clinical data (fractures, bone density, blood testing (bone turnover markers), quality of life, physical disability) as well as administrative data (pharmacological, health services, hospitalization) was collected. Baseline descriptive data was analyzed and presented. RESULTS: Of 542 recruited participants, 532 underwent baseline assessment (85.7% female, mean age 63.4 years). Overall, 29.7% of participants either withdrew from the study or were lost to follow-up. Almost 27% were referred to a specialist, while > 70% received anti-osteoporosis medication prescriptions through the FLS at baseline. Mean femoral T-score was - 1.6 ± 1.0 and vertebral T-score was - 1.7 ± 1.4. Nearly 19% of subjects reported being under anti-osteoporosis medication at the time of incident fracture. Thirty-three percent of participants reported a prior fracture history, of which 29.7% reported being given anti-osteoporosis therapy. Most fracture sites were to the wrist and ankle, while < 19% were hip/femur or vertebral fractures. CONCLUSIONS: These results highlight the important care gap in fragility fracture management and reinforce the need for secondary fracture prevention programs. This prospective study will allow the evaluation of key performance indicators for outpatient clinic-based FLS, such as medication usage, by combining prospective clinical and administrative data.

Incidence of symptomatic venous thromboembolism in 2372 knee and hip replacement patients after discharge: data from a thromboprophylaxis registry in Montreal, Canada.

BACKGROUND: Low-molecular-weight heparin (LMWH) is a recommended anticoagulant for thromboprophylaxis after major orthopedic surgery. Dabigatran etexilate is an oral anticoagulant recognized as noninferior to LMWH. We aimed to assess the incidence of symptomatic venous thromboembolic events (VTEs) after discharge in patients who underwent joint replacement, using a hospital registry. PATIENTS AND METHODS: Patients who underwent total knee and hip arthroplasty between September 2011 and March 2015 were selected. Subcutaneous enoxaparin (30 mg twice daily) was given during hospitalization. At discharge, patients received either enoxaparin 30 mg twice daily/40 mg once daily or dabigatran 220 mg/150 mg once daily. Patients were seen or called at 2, 6, and 12 weeks after surgery. Outcomes were the number of VTEs, including deep venous thrombosis, pulmonary embolism, and the number of major/minor bleeding events after discharge. RESULTS: After discharge, 1468 patients were prescribed enoxaparin and 904 dabigatran (1396 total knee arthroplasty and 976 total hip arthroplasty patients). Mean age was 66±10 years, and 60% were female. The cumulative incidence of VTEs during the 12-week follow-up was 0.7%. One patient sustained a VTE during the switch window. Seven patients sustained a pulmonary embolism (0.3%). There was no statistical difference between the total knee arthroplasty and total hip arthroplasty groups. The incidence of major and minor bleeding events during follow-up was 0.3% and 30.3%, respectively. These events had a higher incidence in the dabigatran group compared to the enoxaparin group after discharge (p<0.05), but not between knee and hip replacement groups for major bleeding events. CONCLUSION: A pharmaceutical prophylaxis protocol using LMWH and dabigatran during the post-discharge period resulted in low incidences of VTE and equivalence between treatments. However, the increased number of major and minor bleeding events in patients taking dabigatran is of concern regarding the safety and needs to be evaluated using analyses adjusted for risk factors.

Synthetic and natural polycations for gene therapy: state of the art and new perspectives.

Currently, the major drawback of gene therapy is the gene transfection rate. The two main types of vectors that are used in gene therapy are based on viral or non-viral gene delivery systems. There are several non-viral systems that can be used to transfer foreign genetic material into the human body. In order to do so, the DNA to be transferred must escape the processes that affect the disposition of macromolecules. These processes include the interaction with blood components, vascular endothelial cells and uptake by the reticuloendothelial system. Furthermore, the degradation of therapeutic DNA by serum nucleases is also a potential obstacle for functional delivery to the target cell. Cationic polymers have a great potential for DNA complexation and may be useful as non-viral vectors for gene therapy applications. The objective of this review was to address the state of the art in gene therapy using synthetic and natural polycations and the latest strategies to improve the efficiency of gene transfer into the cell.

Characterization of folate-chitosan-DNA nanoparticles for gene therapy.

Gene therapy using polymers such as chitosan shows good biocompatibility, but low transfection efficiency. The mechanism of folic acid (FA) uptake by cells to promote targeting and internalization could improve transfection rates. The objective of this study was to synthesize and characterize FA-chitosan-DNA nanoparticles and evaluate their cytotoxicity in vitro. Chitosan-DNA and FA-Chitosan-DNA nanoparticles were prepared using reductive amidation and a complex coacervation process. The effect of charge ratio on the properties of these nanoparticles was monitored by laser scattering. DNA inclusion and integrity was evaluated by gel electrophoresis. Cell viability was illustrated with the MTT assay. Charge ratio (N/P) controlled the nanoparticles size and their zeta potential. Nanoparticles presented a mean size of 118 nm and 80% cellular viability compared to 30% cell viability using LipofectAMINE2000 controls. Gel electrophoresis showed intact DNA within the carriers. FA-nanoparticles have lower cytoxicity, good DNA condensation, positive zeta potential and particle size around 118 nm, which makes them a promising candidate as a non-viral gene vector.