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1.
Br J Surg ; 107(9): 1114-1122, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32187680

RESUMO

BACKGROUND: Placebo-controlled trials play an important role in the evaluation of healthcare interventions. However, they can be challenging to design and deliver for invasive interventions, including surgery. In-depth understanding of the component parts of the treatment intervention is needed to ascertain what should, and should not, be delivered as part of the placebo. Assessment of risk to patients and strategies to ensure that the placebo effectively mimics the treatment are also required. To date, no guidance exists for the design of invasive placebo interventions. This study aimed to develop a framework to optimize the design and delivery of invasive placebo interventions in RCTs. METHODS: A preliminary framework was developed using published literature to: expand the scope of an existing typology, which facilitates the deconstruction of invasive interventions; and identify placebo optimization strategies. The framework was refined after consultation with key stakeholders in surgical trials, consensus methodology and medical ethics. RESULTS: The resulting DITTO framework consists of five stages: deconstruct treatment intervention into constituent components and co-interventions; identify critical surgical element(s); take out the critical element(s); think risk, feasibility and role of placebo in the trial when considering remaining components; and optimize placebo to ensure effective blinding of patients and trial personnel. CONCLUSION: DITTO considers invasive placebo composition systematically, accounting for risk, feasibility and placebo optimization. Use of the framework can support the design of high-quality RCTs, which are needed to underpin delivery of healthcare interventions.


ANTECEDENTES: Los ensayos controlados con placebo juegan un papel importante en la evaluación de las intervenciones sanitarias. Sin embargo, pueden ser difíciles de diseñar e implementar en el caso de intervenciones invasivas, incluida la cirugía. Se necesita un conocimiento profundo de los componentes de la intervención terapéutica (para determinar qué se debe y qué no se debe administrar como parte del placebo). También se precisa de una evaluación del riesgo para los pacientes y de las estrategias para garantizar que el placebo imite el tratamiento de forma efectiva. Hasta la fecha no existen guías para el diseño de intervenciones invasivas con placebo. Este estudio tuvo como objetivo desarrollar un marco para optimizar el diseño y la práctica de intervenciones invasivas con placebo dentro en los ensayos clínicos aleatorizados (ECA). MÉTODOS: Utilizando la literatura publicada, se desarrolló un marco preliminar para i) ampliar el alcance de los modelos existentes para facilitar la deconstrucción de las actuaciones invasivas, y ii) identificar estrategias para optimizar el placebo. El marco se perfeccionó tras consultar con partes interesadas ​​en ensayos quirúrgicos, metodología de consenso y ética médica. RESULTADOS: El marco DITTO resultantes consiste en cinco etapas: Etapa 1: deconstrucción de la intervención de tratamiento en sus componentes esenciales y co-intervenciones; Etapa 2: identificar el(los) elemento(s) quirúrgico(s) básico(s); Etapa 3: eliminar el(los) elemento(s) básico(s); Etapa 4: considerar el riesgo, la viabilidad y el papel del placebo en el ensayo al tener en cuenta los demás componentes; y Etapa 5: optimizar el placebo para garantizar el cegamiento efectivo de los pacientes y del personal del ensayo. CONCLUSIÓN: DITTO considera de forma sistemática la naturaleza invasiva del placebo, teniendo en cuenta el riesgo, la viabilidad y la optimización del placebo. El uso de este marco de referencia puede ayudar al diseño de ECAs de alta calidad, necesarios para afianzar la implementación de intervenciones sanitarias.


Assuntos
Placebos/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Medição de Risco
2.
Anaesthesia ; 75(8): 1050-1058, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32500530

RESUMO

In the UK, tranexamic acid is recommended for all surgical procedures where expected blood loss exceeds 500 ml. However, the optimal dose, route and timing of administration are not known. This study aimed to evaluate current practice of peri-operative tranexamic acid administration. Patients undergoing primary total hip arthroplasty, total knee arthroplasty or unicompartmental knee arthroplasty during a 2-week period were eligible for inclusion in this prospective study. The primary outcome was the proportion of patients receiving tranexamic acid in the peri-operative period. Secondary outcomes included: dose, route and timing of tranexamic acid administration; prevalence of pre- and postoperative anaemia; estimated blood loss; and red blood cell transfusion rates. In total, we recruited 1701 patients from 56 NHS hospitals. Out of these, 1523 (89.5%) patients received tranexamic acid and of those, 1052 (69.1%) received a single dose of 1000 mg intravenously either pre- or intra-operatively. Out of the 1701 patients, 571 (33.6%) and 1386 (81.5%) patients were anaemic (haemoglobin < 130 g.l-1 ) in the pre- and postoperative period, respectively. Mean (SD) estimated blood loss for all included patients was 792 (453) ml and 54 patients (3.1%) received a red blood cell transfusion postoperatively. The transfusion rate for patients with pre-operative anaemia was 6.5%, compared with 1.5% in patients without anaemia. Current standard of care in the UK is to administer 1000 mg of tranexamic intravenously either pre- or intra-operatively. Approximately one-third of patients present for surgery with anaemia, although the overall red blood cell transfusion rate is low. These data provide useful comparators when assessing the efficacy of tranexamic acid and other patient blood management interventions in future studies.


Assuntos
Antifibrinolíticos/uso terapêutico , Artroplastia de Substituição/métodos , Ácido Tranexâmico/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Anemia/complicações , Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue , Estudos de Coortes , Transfusão de Eritrócitos , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos
3.
BMC Musculoskelet Disord ; 20(1): 542, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727033

RESUMO

OBJECTIVE: To evaluate the prevalence and risk factors of wrist pain. METHODS: Systematic review. DATA SOURCES: The MEDLINE and EMBASE via OVID, CINAHL and SPORTDiscus via EBSCO databases were searched from database inception to 9th March 2018. Specific criteria were used to define inclusion and exclusion. Data was extracted independently by a pair of reviewers. RESULTS: In total 32 cross sectional studies were identified for inclusion (1 with a longitudinal component). The median prevalence of wrist pain in the general population and non-manual workers within the short term (within last week) was 6 and 4.2% within the medium term (> 1 week and within a year). The median prevalence of wrist pain in physically demanding occupations and sports people was 10% within the short term and 24% within the medium term. Non-modifiable factors associated with wrist pain included increased age (1 study in adults and 3 studies in children/adolescents) and female sex (2 studies). Modifiable risk factors included high job physical strain (2 studies), high job psychological strain (1 study), abnormal physeal morphology in children/adolescents (2 studies), high frequency impact tool use (1 study) and effort reward imbalance (1 study). CONCLUSIONS: Wrist pain is highly prevalent in groups who partake in physically demanding activities from day to day such as manual labourers and sportspeople. It is less prevalent in the general population and non-manual workers, although there is a relative lack of research in the general population. TRIAL REGISTRATION: The review protocol was registered with PROSPERO under the registration number CRD42018090834. LEVEL OF EVIDENCE: 1 (Prognostic study).


Assuntos
Artralgia/epidemiologia , Traumatismos em Atletas/epidemiologia , Doenças Profissionais/epidemiologia , Traumatismos do Punho/epidemiologia , Articulação do Punho/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artralgia/diagnóstico , Artralgia/fisiopatologia , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/fisiopatologia , Fenômenos Biomecânicos , Criança , Pré-Escolar , Feminino , Humanos , Descrição de Cargo , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/diagnóstico , Doenças Profissionais/fisiopatologia , Saúde Ocupacional , Prevalência , Medição de Risco , Fatores de Risco , Carga de Trabalho , Traumatismos do Punho/diagnóstico , Traumatismos do Punho/fisiopatologia , Adulto Jovem
4.
Soft Matter ; 14(17): 3336-3343, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29658047

RESUMO

The casein micelle is a flexible construct, with its key structural components being casein proteins and colloidal calcium phosphate nanoclusters. According to literature, milk from different species exhibits differences in composition and physicochemical properties. X-ray scattering techniques were used to investigate and compare the nanoscale structure of casein micelles present in cow, goat and sheep milk. Although there were differences in the size and density of larger scale protein structures, at an atomic level the protein structures were similar. There were also strong similarities in the structure of the calcium-containing nanoclusters, namely that they had similar sizes and separations within the casein micelle for all three species.


Assuntos
Caseínas/química , Micelas , Leite/química , Animais , Bovinos , Cabras , Espalhamento a Baixo Ângulo , Ovinos , Difração de Raios X
5.
J Dairy Sci ; 100(4): 2553-2563, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28215884

RESUMO

We isolated goat phosphopeptides via calcium and ethanol precipitation from a caseinate digest and investigated their feasibility as an iron-fortification ingredient in nutritional foods. Goat tryptic-digested phosphopeptides could bind 54.37 ± 0.50 mg of Fe/g of protein compared with goat milk, which could bind 3.83 ± 0.01 mg of Fe/g of protein, indicating that isolation did increase iron binding. However, the >13-fold increase in iron binding was only partly explained by the increased concentration of phosphoserine-rich residues in the isolated fraction: we observed a 77% increase in serine residue content and a 5.9-fold increase in phosphorus in the goat peptide isolate compared with the starting caseinate material. We investigated the effect of potential industrial processing conditions (including heating, cooling, holding time, and processing order) on iron binding by the tryptic-digested phosphopeptides. In addition, we tested the effect of ionic strength and the addition of peptides to a milk system to understand how food formulations could affect iron binding.


Assuntos
Caseínas , Cabras/metabolismo , Quelantes de Ferro , Animais , Ferro , Leite/química , Fosfopeptídeos
6.
Lancet ; 386(9991): 376-87, 2015 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-25748615

RESUMO

Osteoarthritis is a major source of pain, disability, and socioeconomic cost worldwide. The epidemiology of the disorder is complex and multifactorial, with genetic, biological, and biomechanical components. Aetiological factors are also joint specific. Joint replacement is an effective treatment for symptomatic end-stage disease, although functional outcomes can be poor and the lifespan of prostheses is limited. Consequently, the focus is shifting to disease prevention and the treatment of early osteoarthritis. This task is challenging since conventional imaging techniques can detect only quite advanced disease and the relation between pain and structural degeneration is not close. Nevertheless, advances in both imaging and biochemical markers offer potential for diagnosis and as outcome measures for new treatments. Joint-preserving interventions under development include lifestyle modification and pharmaceutical and surgical modalities. Some show potential, but at present few have proven ability to arrest or delay disease progression.


Assuntos
Osteoartrite/diagnóstico , Osteoartrite/terapia , Biomarcadores/metabolismo , Progressão da Doença , Diagnóstico Precoce , Humanos , Estilo de Vida , Osteoartrite/epidemiologia
7.
Osteoarthritis Cartilage ; 24(5): 883-91, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26687825

RESUMO

OBJECTIVE: Dickkopf-3 (Dkk3) is a non-canonical member of the Dkk family of Wnt antagonists and its upregulation has been reported in microarray analysis of cartilage from mouse models of osteoarthritis (OA). In this study we assessed Dkk3 expression in human OA cartilage to ascertain its potential role in chondrocyte signaling and cartilage maintenance. METHODS: Dkk3 expression was analysed in human adult OA cartilage and synovial tissues and during chondrogenesis of ATDC5 and human mesenchymal stem cells. The role of Dkk3 in cartilage maintenance was analysed by incubation of bovine and human cartilage explants with interleukin-1ß (IL1ß) and oncostatin-M (OSM). Dkk3 gene expression was measured in cartilage following murine hip avulsion. Whether Dkk3 influenced Wnt, TGFß and activin cell signaling was assessed in primary human chondrocytes and SW1353 chondrosarcoma cells using qRT-PCR and luminescence assays. RESULTS: Increased gene and protein levels of Dkk3 were detected in human OA cartilage, synovial tissue and synovial fluid. DKK3 gene expression was decreased during chondrogenesis of both ATDC5 cells and humans MSCs. Dkk3 inhibited IL1ß and OSM-mediated proteoglycan loss from human and bovine cartilage explants and collagen loss from bovine cartilage explants. Cartilage DKK3 expression was decreased following hip avulsion injury. TGFß signaling was enhanced by Dkk3 whilst Wnt3a and activin signaling were inhibited. CONCLUSIONS: We provide evidence that Dkk3 is upregulated in OA and may have a protective effect on cartilage integrity by preventing proteoglycan loss and helping to restore OA-relevant signaling pathway activity. Targeting Dkk3 may be a novel approach in the treatment of OA.


Assuntos
Cartilagem Articular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Osteoartrite/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Células Cultivadas , Quimiocinas , Condrogênese/fisiologia , Relação Dose-Resposta a Droga , Regulação para Baixo/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Técnicas de Cultura de Tecidos , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/fisiologia , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/fisiologia
8.
Soft Matter ; 12(33): 6937-53, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-27491477

RESUMO

An in-depth, critical review of model-dependent fitting of small-angle X-ray scattering (SAXS) data of bovine skim milk has led us to develop a new mathematical model for interpreting these data. Calcium-edge resonant soft X-ray scattering data provides unequivocal evidence as to the shape and location of the scattering due to colloidal calcium phosphate, which is manifested as a correlation peak centred at q = 0.035 Å(-1). In SAXS data this feature is seldom seen, although most literature studies attribute another feature centred at q = 0.08-0.1 Å(-1) to CCP. This work shows that the major SAXS features are due to protein arrangements: the casein micelle itself; internal regions approximately 20 nm in size, separated by water channels; and protein structures which are inhomogeneous on a 1-3 nm length scale. The assignment of these features is consistent with their behaviour under various conditions, including hydration time after reconstitution, addition of EDTA (a Ca-chelating agent), addition of urea, and reduction of pH.

9.
Soft Matter ; 11(14): 2723-5, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25711160

RESUMO

The interpretation of milk X-ray and neutron scattering data in relation to the internal structure of the casein micelle is an ongoing debate. We performed resonant X-ray scattering measurements on liquid milk and conclusively identified key scattering features, namely those corresponding to the size of and the distance between colloidal calcium phosphate particles. An X-ray scattering feature commonly assigned to the particle size is instead due to protein inhomogeneities.


Assuntos
Caseínas/química , Micelas , Animais , Leite/química , Tamanho da Partícula , Espalhamento de Radiação , Difração de Raios X
10.
Osteoarthritis Cartilage ; 22(2): 218-25, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24269636

RESUMO

INTRODUCTION: Cam impingement is characterized by abnormal contact between the proximal femur and acetabulum caused by a non-spherical femoral head, known as a cam deformity. A cam deformity is usually quantified by the alpha angle; greater alpha angles substantially increase the risk for osteoarthritis (OA). However, there is no consensus on which alpha angle threshold to use to define the presence of a cam deformity. AIM: To determine alpha angle thresholds that define the presence of a cam deformity and a pathological cam deformity based on development of OA. METHODS: Data from both the prospective CHECK cohort of 1002 individuals (45-65 years) and the prospective population-based Chingford cohort of 1003 women (45-64 years) with respective follow-up times of 5 and 19 years were combined. The alpha angle was measured at baseline on anteroposterior radiographs, from which a threshold for the presence of a cam deformity was determined based on its distribution. Further, a pathological alpha angle threshold was determined based on the highest discriminative ability for development of end-stage OA at follow-up. RESULTS: A definite bimodal distribution of the alpha angle was found in both cohorts with a normal distribution up to 60°, indicating a clear distinction between normal and abnormal alpha angles. A pathological threshold of 78° resulted in the maximum area under the ROC curve. CONCLUSION: Epidemiological data of two large cohorts shows a bimodal distribution of the alpha angle. Alpha angle thresholds of 60° to define the presence of a cam deformity and 78° for a pathological cam deformity are proposed.


Assuntos
Impacto Femoroacetabular/patologia , Idoso , Estudos de Coortes , Inglaterra/epidemiologia , Feminino , Impacto Femoroacetabular/complicações , Impacto Femoroacetabular/diagnóstico por imagem , Impacto Femoroacetabular/epidemiologia , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/patologia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Osteoartrite do Quadril/epidemiologia , Osteoartrite do Quadril/etiologia , Osteoartrite do Quadril/patologia , Radiografia , Reprodutibilidade dos Testes
11.
Osteoarthritis Cartilage ; 22(10): 1504-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25047637

RESUMO

OBJECTIVE: Femoroacetabular Impingement (FAI) and Acetabular Dysplasia are common deformities, which have been implicated as a major cause of hip osteoarthritis (OA). We examined whether these subtle deformities of the hip are associated with the development of radiographic OA and total hip replacement (THR) in women. DESIGN: A population-based, longitudinal cohort of 1003 women underwent pelvis radiographs at years 2 and 20. Alpha Angle, Triangular Index Height, Lateral Centre Edge (LCE) angle and Extrusion Index were measured. An alpha angle of greater than 65° was defined as Cam-type FAI. Radiographic OA and the presence of a THR were then determined at 20 years. RESULTS: Cam-type FAI was significantly associated with the development of radiographic OA. Each degree increase in alpha angle above 65° was associated with an increase in risk of 5% (Odds Ratio (OR) 1.05 [95% confidence interval (CI) 1.01-1.09]) for radiographic OA and 4% (OR 1.04 [95% CI 1.00-1.08]) for THR. For Acetabular Dysplasia, each degree reduction in LCE angle below 28° was associated with an increase in risk of 13.0% (OR 0.87 [95% CI 0.78-0.96]) for radiographic OA and 18% (OR 0.82 [95% CI 0.75-0.89]) for THR. CONCLUSIONS: This study demonstrates that Cam-type FAI and mild Acetabular Dysplasia are predictive of subsequent OA and THR in a large female population cohort. These are independent of age, BMI and joint space and significantly improve current predictive models of hip OA development.


Assuntos
Artroplastia de Quadril/estatística & dados numéricos , Impacto Femoroacetabular/epidemiologia , Luxação do Quadril/epidemiologia , Articulação do Quadril/anormalidades , Osteoartrite do Quadril/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Estudos de Coortes , Feminino , Impacto Femoroacetabular/diagnóstico por imagem , Luxação do Quadril/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Razão de Chances , Osteoartrite do Quadril/diagnóstico por imagem , Osteoartrite do Quadril/cirurgia , Estudos Prospectivos , Radiografia , Fatores de Risco
12.
Osteoarthritis Cartilage ; 21(2): 314-21, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23123686

RESUMO

OBJECTIVE: Genetic factors and abnormalities of joint morphology are important in the aetiology of hip osteoarthritis (OA). The extent to which genetic influences are manifest through joint morphology has undergone limited investigation. Using a cohort with an hereditary predisposition to end-stage hip OA and a control group with no inherited risk, we aimed to identify associations with abnormal joint morphology and clinical features. DESIGN: One hundred and twenty-three individuals (mean age 52 years) with a family history of total hip arthroplasty (THA) (termed 'sibkids') were compared with 80 spouse controls. Morphology was assessed using standardised radiographs and cam, dysplasia, and pincer deformities defined. Regression modelling described the association of cohort with abnormal joint morphology, adjusting for confounders [age, gender, body mass index (BMI), OA, and osteophyte]. RESULTS: Sibkids had an odds ratio of 2.1 [95%confidence interval (CI) 1.3-3.5] for cam deformity. There were no differences in the prevalence of dysplasia or pincer deformities. In both groups, hips with cam deformities or dysplasia were more likely to have clinical features than normal hips [odds ratio (OR) 4.46 (1.8-11.3), and 4.40 (1.4-14.3) respectively]. Pincer deformity was associated with positive signs in the sibkids but not in the controls (OR 3.0; 1.1-8.2). DISCUSSION: After adjustment for confounders that cause secondary morphological change, individuals with an hereditary predisposition to end-stage hip OA had a higher prevalence of morphological abnormalities associated with hip OA. Sibkids were more likely to demonstrate clinical features in the presence of pincer deformity, suggesting that the genes are acting not only through abnormal morphology but also through other factors that influence the prevalence of pain.


Assuntos
Predisposição Genética para Doença/genética , Articulação do Quadril/anormalidades , Osteoartrite do Quadril/epidemiologia , Osteoartrite do Quadril/genética , Acetábulo/anormalidades , Acetábulo/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Intervalos de Confiança , Feminino , Fêmur/anormalidades , Fêmur/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Radiografia
13.
Osteoporos Int ; 24(4): 1471-81, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22907737

RESUMO

UNLABELLED: Bisphosphonates reduce skeletal loss and fracture risk, but their use has been limited in patients with chronic kidney disease. This study shows skeletal benefits of zoledronic acid in an animal model of chronic kidney disease. INTRODUCTION: Bisphosphonates are routinely used to reduce fractures but limited data exists concerning their efficacy in non-dialysis chronic kidney disease. The goal of this study was to test the hypothesis that zoledronic acid produces similar skeletal effects in normal animals and those with kidney disease. METHODS: At 25 weeks of age, normal rats were treated with a single dose of saline vehicle or 100 µg/kg of zoledronic acid while animals with kidney disease (approximately 30% of normal kidney function) were treated with vehicle, low dose (20 µg/kg), or high dose (100 µg/kg) zoledronic acid, or calcium gluconate (3% in the drinking water). Skeletal properties were assessed 5 weeks later using micro-computed tomography, dynamic histomorphometry, and mechanical testing. RESULTS: Animals with kidney disease had significantly higher trabecular bone remodeling compared to normal animals. Zoledronic acid significantly suppressed remodeling in both normal and diseased animals yet the remodeling response to zoledronic acid was no different in normal and animals with kidney disease. Animals with kidney disease had significantly lower cortical bone biomechanical properties; these were partially normalized by treatment. CONCLUSIONS: Based on these results, we conclude that zoledronic acid produces similar amounts of remodeling suppression in animals with high turnover kidney disease as it does in normal animals, and has positive effects on select biomechanical properties that are similar in normal animals and those with chronic kidney disease.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Remodelação Óssea/efeitos dos fármacos , Difosfonatos/farmacologia , Imidazóis/farmacologia , Insuficiência Renal Crônica/fisiopatologia , Animais , Fenômenos Biomecânicos , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Remodelação Óssea/fisiologia , Diáfises/efeitos dos fármacos , Diáfises/fisiopatologia , Difosfonatos/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fêmur/efeitos dos fármacos , Fêmur/fisiopatologia , Imidazóis/administração & dosagem , Masculino , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley , Tíbia/efeitos dos fármacos , Tíbia/patologia , Tíbia/fisiopatologia , Ácido Zoledrônico
14.
Osteoarthritis Cartilage ; 20(5): 368-375, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22343497

RESUMO

OBJECTIVE: Genetic factors are important in the aetiology of hip osteoarthritis (OA), but studies are limited by cross-sectional design and poor association with clinically important disease. Identifying cohorts with progressive OA will facilitate development of OA biomarkers. Using a middle-aged cohort with genetic predisposition to hip OA and a control group, we compared the prevalence of clinical and radiographic hip OA and incidence of progression over 5 years. DESIGN: 123 individuals (mean age 52 years) with a family history of total hip arthroplasty (THA) ('sibkids') were compared with 80 (mean age 54 years) controls. The prevalence of radiographic OA [scored according to Kellgren & Lawrence (K&L)], clinical features, and incidence of clinical progression over a 5-year period were compared. A multivariate logistic regression model was used to adjust for confounders. RESULTS: Sibkids had odds ratios (ORs) of 2.7 [95% confidence interval (CI) 1.1-6.3, P = 0.02] for hip OA (K&L grade ≥2), 3.4 (1.4-8.4, P = 0.008) for clinical signs, and 2.1 (0.8-5.8, P = 0.14) for signs and symptoms. Over 5 years, sibkids had ORs of 4.7 (1.7-13.2, P = 0.003) for the development of signs, and 3.2 (1.0-10.3, P = 0.047) for the development of signs and symptoms. DISCUSSION: Compared to a control group and after adjustment for confounders, individuals with genetic predisposition to end-stage hip OA have higher prevalence of OA, clinical features, and progression. In addition to structural degeneration, the inherited risk may include predisposition to pain. Genetically-loaded cohorts are useful to develop hip OA biomarkers, as they develop progressive disease at a young age.


Assuntos
Osteoartrite do Quadril/genética , Idoso , Artroplastia de Quadril , Estudos de Casos e Controles , Fatores de Confusão Epidemiológicos , Progressão da Doença , Feminino , Seguimentos , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/diagnóstico por imagem , Osteoartrite do Quadril/cirurgia , Radiografia
15.
Eur Cell Mater ; 24: 344-57; discussion 357, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-23090765

RESUMO

Rotator cuff tendon pathology is thought to account for 30-70 % of all shoulder pain. For cases that have failed conservative treatment, surgical re-attachment of the tendon to the bone with a non-absorbable suture is a common option. However, the failure rate of these repairs is high, estimated at up to 75 %. Studies have shown that in late disease stages the tendon itself is extremely degenerate, with reduced cell numbers and poor matrix organisation. Thus, it has been suggested that adding biological factors such as platelet rich plasma (PRP) and mesenchymal stem cells could improve healing. However, the articular capsule of the glenohumeral joint and the subacromial bursa are large spaces, and injecting beneficial factors into these sites does not ensure localisation to the area of tendon damage. Thus, the aim of this study was to develop a biocompatible patch for improving the healing rates of rotator cuff repairs. The patch will create a confinement around the repair area and will be used to guide injections to the vicinity of the surgical repair. Here, we characterised and tested a preliminary prototype of the patch utilising in vitro tools and primary tendon-derived cells, showing exceptional biocompatibility despite rapid degradation, improved cell attachment and that cells could migrate across the patch towards a chemo-attractant. Finally, we showed the feasibility of detecting the patch using ultrasound and injecting liquid into the confinement ex vivo. There is a potential for using this scaffold in the surgical repair of interfaces such as the tendon insertion in the rotator cuff, in conjunction with beneficial factors.


Assuntos
Polidioxanona/metabolismo , Tendões/citologia , Adesão Celular , Linhagem Celular , Movimento Celular , Proliferação de Células , Humanos , Teste de Materiais , Manguito Rotador , Tendões/metabolismo , Cicatrização
16.
J Mater Sci Mater Med ; 23(3): 823-33, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22198644

RESUMO

Tissue engineering scaffolds encourage cell proliferation whilst degrading to facilitate tissue regeneration. Their mechanical properties therefore change, decreasing due to scaffold degradation and increasing due to extracellular matrix deposition. This work compares the changing properties of collagen scaffolds incubated in culture medium, with and without human tenocytes, in order to investigate the relationship between degradation and tenocyte proliferation. The material properties of scaffolds are compared over 26 days using mechanical testing, differential scanning calorimetry, infra-red spectroscopy, and histology and biochemical assays. For medium-only scaffolds, the mechanical properties decrease rapidly, while culture medium sulfhydryl content increases significantly, with no significant changes in the denaturation temperature of scaffold collagen content. Conversely, the mechanical properties and collagen content of tenocyte-seeded scaffolds increase significantly while culture medium sulfhydryl content decreases and denaturation temperature remains the same. These results indicate that tenocytes proliferation both reduces the degradation of collagen scaffolds incubated in culture medium and produces scaffolds with improved properties.


Assuntos
Proliferação de Células , Colágeno/química , Tendões/citologia , Engenharia Tecidual , Varredura Diferencial de Calorimetria , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Osteoarthritis Cartilage ; 19(2): 155-62, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20951814

RESUMO

OBJECTIVES: There is an increasing movement to collect and report patient reported outcome measures (PROM's) following total hip replacement (THR). In the UK, the procedure specific PROM of choice is the Oxford Hip Score (OHS). It is currently unclear how to use this information to determine outcome following surgery. The aim of this study was to define a threshold for the OHS that is correlated with patient satisfaction. DESIGN: Prospective cohort study. SETTING: A district general hospital (St. Helier Hospital, Carshalton, UK). PARTICIPANTS: 799 patients receiving THR from 1995 to 2004. MAIN OUTCOME MEASURES: At 12 and 24 months after surgery patients were asked if they were satisfied with surgery and completed the OHS. Receiver operating characteristic (ROC) analyses were used to identify thresholds of follow-up OHS, which best discriminated patient satisfaction. Analyses were stratified by age, sex, body mass index (BMI), baseline OHS and patient expectations. RESULTS: 91.9% of patients were satisfied with THR at 12 months (92.8% at 24 months). Using the ROC technique, the OHS at 12 months associated with patient satisfaction was 38 and at 24 months 33. The OHS at 24 months associated with satisfaction was higher in those with highest tertile of baseline OHS (30, 33, 43 respectively), and lowest tertile of BMI. CONCLUSIONS: We have identified a value of the OHS that predicts patient satisfaction 12-24 months following THR within a standard clinical setting. However, this threshold is markedly influenced by pre-operative OHS and should be stratified accordingly.


Assuntos
Artroplastia de Quadril , Avaliação de Resultados em Cuidados de Saúde , Satisfação do Paciente , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Inquéritos e Questionários/normas
18.
Osteoarthritis Cartilage ; 18(2): 200-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19733643

RESUMO

OBJECTIVE: Several research groups have examined osteoarthritis (OA) association with Interleukin-1 (IL-1) region markers and haplotypes. The results have been suggestive for hand OA, negative for knee OA, and conflicting for hip OA. DESIGN: Our aim was to address conflicts employing meta-analytical methods on data from 1238 European-descent cases with various OA phenotypes and 1269 European-descent controls from four study centers. We imputed some missing genotype data and reconstructed IL-1 region extended haplotypes. A previously reported 7-marker IL1A-IL1B-IL1RN extended risk haplotype was tested for association with each specific index phenotype. RESULTS: For hip OA, data from three centers showed heterogeneity of extended-risk-haplotype effect, two panels showing trend toward risk and another showing protection, with overall odds ratio (OR) 1.24 (95% Confidence interval (CI) 0.45-3.41, P 0.67). The heterogeneity fell partly along control ascertainment lines, chiefly between controls ascertained as spouses of arthroplasty patients and controls identified through population radiographic survey. For knee OA, the results showed no heterogeneity and no significant extended-risk-haplotype effect. For hand OA, the results showed little heterogeneity and a modest trend toward positive association (summary OR 1.34, 95% CI 0.83-2.17 P 0.23). Using a Bayesian partition modeling approach, the 7-marker extended haplotypes showed no significant effect on any OA phenotype examined. A 3-single-nucleotide polymorphism (SNP) IL1B-IL1RN haplotype rs1143627-rs16944-rs419598 showed a trend toward hand OA association (posterior probability of association 0.72) with the most prominent feature being protection from a specific haplotype representing a partial mirror image of the extended risk haplotype (OR estimated at 0.46). CONCLUSIONS: The meta-analysis data do not confirm but only suggest that some hand and hip OA risk could be associated with the IL-1 region, particularly centered in IL1B and possibly also IL1RN.


Assuntos
Predisposição Genética para Doença/genética , Haplótipos/genética , Interleucina-1/genética , Osteoartrite do Quadril/genética , Osteoartrite do Joelho/genética , Frequência do Gene/genética , Marcadores Genéticos , Genótipo , Humanos , Fenótipo , Polimorfismo de Nucleotídeo Único , População Branca/genética
19.
PLoS One ; 15(4): e0230235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240199

RESUMO

BACKGROUND: Rotator cuff tears are a common cause of shoulder pain and can result in prolonged periods of pain, disability and absence from work. Rotator cuff repair surgery is increasingly used in an attempt to resolve symptoms but has failure rates of around 40%. There is a pressing need to improve the outcome of rotator cuff repairs. Patch augmentation increasingly being used within the NHS in an attempt to reduce repair failures. The aim of this survey was to determine current UK practice and opinion relating to the factors that influence choice of patch, current patient selection and willingness to assist with generation of improved evidence. METHODS: An online survey was sent to the surgeon members of the British Elbow and Shoulder Society (BESS). Questions covered respondent demographics, experience with patches, indications for patch augmentation and willingness to be involved in a randomised trial of patch augmented rotator cuff surgery. RESULTS: The response rate was 105/550 (19%). 58% of respondents had used a patch to augment rotator cuff surgery. 70% of patch users had undertaken an augmented repair within the last 6 months. A wide surgical experience in augmentation was reported (ranging 1 to 200 implants used). However, most surgeons reported low volume usage, with a median of 5 rotator cuff augmentation procedures performed. At least 10 different products had been used. Most of the patches used were constructed from human decellularised dermis tissue, although porcine derived and synthetic based patches had also been used. Only 3-5% stated they would undertake an augmented repair for small tears across ages, whereas 28-40% and 19-59% would do so for large or massive tears respectively. When assessing patient suitability, patient age seemed relevant only for those with large and massive tears. Half of the surgeons reported an interest in taking part in a randomised controlled trial (RCT) evaluating the role of patch augmentation for rotator cuff surgery, with a further 22% of respondent's undecided. CONCLUSIONS: A variety of patches have been used by surgeons to augment rotator cuff repair with a wide range of operator experience. There was substantial uncertainty about which patch to use and differing views on which patients were most suitable. There is a clear need for robust clinical evaluation and further research in this area.


Assuntos
Artroplastia/métodos , Artroscopia/métodos , Tomada de Decisão Clínica/métodos , Lesões do Manguito Rotador/cirurgia , Manguito Rotador/cirurgia , Idoso , Idoso de 80 Anos ou mais , Animais , Cotovelo/inervação , Cotovelo/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Próteses e Implantes , Manguito Rotador/inervação , Manguito Rotador/patologia , Lesões do Manguito Rotador/patologia , Ombro/inervação , Ombro/patologia , Ombro/cirurgia , Dor de Ombro/prevenção & controle , Dor de Ombro/cirurgia , Inquéritos e Questionários , Suínos , Resultado do Tratamento , Incerteza , Reino Unido , Lesões no Cotovelo
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