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1.
Osteoporos Int ; 34(10): 1763-1770, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37341729

RESUMO

A national hip fracture registry does not yet exist in China. This is the first to recommend a core variable set for the establishment of a Chinese national hip fracture registry. Thousands of Chinese hospitals will build on this and improve the quality of management for older hip fracture patients. The rapidly ageing population of China already experiences over half a million hip fractures every year. Many countries have developed national hip fracture registries to improve the quality of hip fracture management, but such a registry does not exist in China. The study is aimed at determining the core variables of a national hip fracture registry for older hip fracture patients in China. A rapid literature review was conducted to develop a preliminary pool of variables from existing global hip fracture registries. Two rounds of an e-Delphi survey were conducted with experts. The e-Delphi survey used a Likert 5-point scale and boundary value analysis to filter the preliminary pool of variables. The list of core variables was finalised following an online consensus meeting with the experts. Thirty-one experts participated. Most of the experts have senior titles and have worked in a corresponding area for more than 15 years. The response rate of the e-Delphi was 100% for both rounds. The preliminary pool of 89 variables was established after reviewing 13 national hip fracture registries. With two rounds of the e-Delphi and the expert consensus meeting, 86 core variables were recommended for inclusion in the registry. This study is the first to recommend a core variable set for the establishment of a Chinese national hip fracture registry. The further development of a registry to routinely collect data from thousands of hospitals will build on this work and improve the quality of management for older hip fracture patients in China.


Assuntos
Fraturas do Quadril , Humanos , Técnica Delphi , Sistema de Registros , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/cirurgia , China/epidemiologia
2.
Osteoporos Int ; 33(10): 2185-2192, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35763077

RESUMO

Prevalence of cognitive impairment in hip fractures was 86.5%. MoCA is an independent risk factor of mortality. MoCA score of < 15 is correlated with 11.71 times increased risk of mortality. Early attention and caution should be given to these patients for appropriate intervention to decrease mortality rates. INTRODUCTION: Hip fractures rank amongst the top 10 causes of disability and current mortality of hip fractures is high. Objectives were to determine 1) prevalence of cognitive impairment, 2) whether Montreal Cognitive Assessment (MoCA) score was an independent risk factor associated with mortality, 3) MoCA cut-off that result in high risk of mortality. METHODS: This was a cohort study between July 2019 to June 2020. Inclusion criteria were 1) hip fracture, 2) > = 65 years old, and 3) low-energy trauma. Patients undergo assessment for cognitive impairment with MoCA. Prevalence was assessed, MoCA cut-off point, and accuracy of statistical model was evaluated. Logistic regression modelling was used to assess association between mortality and MoCA. RESULTS: There were 260 patients recruited. Two hundred twenty-five patients had MoCA score < 22 signifying cognitive impairment, and 202 patients had MoCA score of < 19. 46 hip fracture patients died at 1-year follow-up. 45 of these patients had MoCA score < 19, and 1 patient had a MoCA > 22. Results showed statistical significance and good model effect (at least 0.8) with MoCA cut-off points between < 15 and < 19 (p < 0.05). After controlling confounding factors, statistical significance still existed in MoCA cut-off point at < 15 (odds ratio (95% CI) = 11.71 (1.14, 120.71); p = 0.04). CONCLUSION: Prevalence of cognitive impairment in hip fractures was 86.5%. MoCA is an independent risk factor of mortality in hip fracture patients. MoCA score of < 15 is correlated with 11.71 times increased risk of mortality at 1-year after a hip fracture. AUC with MoCA score < 15 was 0.948. Early attention and caution should be given to these patients for appropriate intervention to decrease mortality rates.


Assuntos
Disfunção Cognitiva , Fraturas do Quadril , Idoso , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Estudos de Coortes , Fraturas do Quadril/complicações , Humanos , Testes de Estado Mental e Demência , Testes Neuropsicológicos , Fatores de Risco
3.
Stud Health Technol Inform ; 280: 66-71, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34190063

RESUMO

To establish the age- and sex-related normative values of sagittal alignment in asymptomatic Chinese adults, and to investigate the changes and possible associated compensation mechanisms across age groups. 584 asymptomatic Chinese adults aged 20-89 years were recruited. Subjects were grouped according to age and gender. Whole-body standing radiographs were acquired for evaluating sagittal alignment from spine to lower limb. Sagittal parameters between gender in different age groups were compared via independent t test. Pearson correlation analysis was used to demonstrate relationships between parameters. Thoracic kyphosis (TK) increased steadily while lumbar lordosis decreased gradually in both genders. Pelvic tilt (PT) in male is greater than in female across all age groups with age related gradual increase. There were significant differences between male and female from 20s to 60s in terms of knee flexion angle (KA) and ankle dorsiflexion angle (AA), but the differences were not significant after 60s. T1 pelvic angle (TPA) was significantly correlated with spinal, pelvic and lower-limb alignment. The older group (≥50 years) had a stronger correlation of TPA with PT and KA, whereas the younger (<50 years) had stronger correlation with TK. This study comprehensively presented the normative sagittal alignment based on a large asymptomatic population, which could serve as an age- and gender-specific reference value for spine surgeons when planning for correction surgery. Age can influence the recruitment of compensation mechanism that involve more pelvic and lower limb mechanisms for elderly people.


Assuntos
Cifose , Lordose , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Cifose/diagnóstico por imagem , Lordose/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Coluna Vertebral , Adulto Jovem
4.
J Orthop Translat ; 24: 58-65, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32695605

RESUMO

OBJECTIVE: To analyze the effectiveness of exercise interventions on falls and fall-related fracture prevention among community-dwelling elderlies. METHODS: Literature search was conducted in Pubmed and Embase. Keywords used for literature search were "fracture" AND "fall" AND "exercise". Randomized controlled trials involving community-dwelling elderlies older than 60 years old with physical exercises as intervention were included. A systematic review and meta-analysis was performed. The primary outcomes were falls and fractures. RESULTS: Twelve studies were included and 4784 participants were involved with a mean age of 75.4. The most common exercise interventions were strength and balance exercises. The results of meta-analysis of 11 studies showed that exercise intervention had beneficial effect on fall prevention (RR = 0.71, 95% CI, 0.62-0.82; I2 = 24%, p < 0.0001). The effect was better when exercise intervention applied to women participants (RR = 0.64, 95% CI, 0.49-0.83; I2 = 28%, p = 0.00009) compared to men and women participants (RR = 0.75, 95% CI, 0.64-0.89; I2 = 24%, p = 0.001). The results of meta-analysis of seven studies showed that physical exercise had significant effect on fracture prevention (RR = 0.54, 95% CI, 0.35-0.83; I2 = 25%, p = 0.005). However, the effect was significant when exercise intervention applied to women participants only (RR = 0.37, 95% CI, 0.20-0.67; I2 = 0%, p = 0.001) but not significant when exercise intervention applied to both genders (RR = 0.80, 95% CI, 0.58-1.09; I2 = 0%, p = 0.15). CONCLUSION: Exercise interventions, especially the combination of strength and balance training, were effective in preventing falls. Resistance exercises and jumping exercises were effective for fracture prevention among community-dwelling older population. The effectiveness of exercise interventions on fracture prevention have more significant effect on women. Further studies are needed to test the effectiveness of exercise interventions in men. TRANSLATIONAL POTENTIAL: The use of effective exercises or biophysical interventions including vibration therapy can be incorporated into Fracture Liaison Services to prevent future fall and fracture.

5.
Eur Cell Mater ; 38: 228-245, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31697398

RESUMO

Fracture healing is a well-orchestrated and coordinated process and begins with the inflammatory stage involving the infiltration of immune cells and the release of cytokines, including tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-10 (IL-10). Low-magnitude high-frequency vibration (LMHFV) stimulation is effective in promoting fracture healing. The study hypothesis was that the innate immune response was impaired in osteoporotic fracture and LMHFV could positively modulate it. 9-month-old ovariectomy (OVX)-induced osteoporotic rats were randomised into sham (SHAM), OVX control (OVX), OVX-vibration (OVX-VT) or OVX vibration plus administration of COX-2 specific non-steroid anti-inflammatory drugs (OVX-VT-NSAID). LMHFV (35 Hz, 0.3 g) was given 20 min/d and 5 d/week to the treatment groups. Healing and innate immune response were evaluated by weekly radiographs, endpoint micro-computed tomography (µCT), enzyme-linked immunosorbent assay (ELISA) and histomorphometry at weeks 1, 2, 4 and 8 post-treatment. Results showed that OVX slightly elevated systemic inflammation but impaired the innate immune response locally at the fracture site, with significantly lower expressions of TNF-α and IL-6 but higher IL-10 expression during the early stage of healing. LMHFV was effective in accelerating the delayed fracture healing in OVX bones by partly restoring the impaired innate immune response at the fracture site, accompanied by promoted progression of macrophage polarisation from M1 (pro-inflammatory) to M2 (anti-inflammatory) phenotype. In conclusion, vibration treatment could positively modulate the impaired innate immune response and promote macrophage polarisation in osteoporotic-fracture healing.


Assuntos
Consolidação da Fratura , Macrófagos/citologia , Fraturas por Osteoporose/terapia , Vibração/uso terapêutico , Animais , Diferenciação Celular , Estrogênios/deficiência , Feminino , Imunidade Inata , Interleucina-10/genética , Interleucina-10/metabolismo , Macrófagos/metabolismo , Fraturas por Osteoporose/etiologia , Ratos , Ratos Sprague-Dawley
7.
Eur Cell Mater ; 37: 420-430, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-31115897

RESUMO

Most osteoporotic fractures occur at metaphyseal regions of long bones. The present study proposed a clinically relevant animal model that satisfied: i) induction of osteoporosis, ii) unilateral complete osteotomy at metaphysis, iii) internal fixation. 6 months old female Sprague-Dawley rats (n = 64) were randomly divided into the ovariectomised-metaphyseal osteotomy (OVX, n = 32) and metaphyseal osteotomy (SHAM, n = 32) groups. The metaphyseal-osteotomy model was created with a plate-fixation of the osteotomy and assessed by X-ray, micro-computed tomography, histomorphometry and mechanical testing at weeks 1, 3 and 6. X-ray results showed complete healing of metaphyseal osteotomy at week 6. Histology showed 3 stages of metaphyseal healing. Stage 1 was characterised by fibrous tissue, consisting of disorganised orientation of collagen fibres, and infiltration of immune cells. At stage 2, a transitional zone consisting of maturing fibrous tissue and differentiating mesenchymal cells with early trabecular bone formation and disorganised woven bone were observed. During stage 3, cortical bone ends unified and woven bone underwent transformation to lamellar bone. OVX group healing was significantly delayed when compared to SHAM samples. The study demonstrated that healing of osteoporotic osteotomy at the metaphyseal region was delayed in terms of radiography, histomorphometry and mechanical strength. These quantitative evaluations, along with histological features, may provide key references for future studies. The animal model may provide additional clinical relevance as most osteoporotic fracture in humans occurs at metaphyseal regions.


Assuntos
Osso e Ossos/fisiopatologia , Osteoporose/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Animais , Modelos Animais de Doenças , Feminino , Fixação Interna de Fraturas/métodos , Consolidação da Fratura/fisiologia , Osteotomia/métodos , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X/métodos
8.
Osteoporos Int ; 30(3): 541-553, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30610245

RESUMO

Sarcopenia is a common geriatric syndrome characterized by progressive decrease of muscle mass and function leading to an increased risk of physical disability, poor quality of life, and mortality. Increasing evidence shows that sarcopenia is related with fragility fractures. This systematic review aimed to summarize the following: (1) the prevalence of sarcopenia in patients with fragility fracture and (2) the associated risk factors for fragility fracture in patients with sarcopenia. Literature search was conducted in PubMed and Cochrane databases. Studies with the prevalence of sarcopenia in elderly patients with fragility fracture and associated risk factors in patients with sarcopenia were included. A total of 15 papers were included, with 10 reporting sarcopenia prevalence, and 5 on fracture risk in patients with sarcopenia. The prevalence of sarcopenia after fracture ranged from 12.4 to 95% in males and 18.3 to 64% in females. The prevalence of sarcopenia in elderly patients with fragility fracture was high, especially in men. Two studies showed that sarcopenia was a risk factor for fragility fracture when associated with low bone mineral density (BMD) but only in men. Caution should be taken for male patients with sarcopenia and low BMD, which is related to significantly increased risk of fractures. There is a pressing need for further research on sarcopenia and its risk on fragility fracture to better understand the relationship, pathophysiology, and mechanisms, which may shed light on potential interventions to improve clinical outcomes.


Assuntos
Fraturas por Osteoporose/etiologia , Sarcopenia/complicações , Densidade Óssea/fisiologia , Humanos , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/fisiopatologia , Prevalência , Fatores de Risco , Sarcopenia/epidemiologia , Sarcopenia/fisiopatologia
9.
Bone Joint Res ; 7(1): 6-11, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29305425

RESUMO

OBJECTIVES: The treatment of osteoporotic fractures is a major challenge, and the enhancement of healing is critical as a major goal in modern fracture management. Most osteoporotic fractures occur at the metaphyseal bone region but few models exist and the healing is still poorly understood. A systematic review was conducted to identify and analyse the appropriateness of current osteoporotic metaphyseal fracture animal models. MATERIALS AND METHODS: A literature search was performed on the Pubmed, Embase, and Web of Science databases, and relevant articles were selected. A total of 19 studies were included. Information on the animal, induction of osteoporosis, fracture technique, site and fixation, healing results, and utility of the model were extracted. RESULTS: Fracture techniques included drill hole defects (3 of 19), bone defects (3 of 19), partial osteotomy (1 of 19), and complete osteotomies (12 of 19). Drill hole models and incomplete osteotomy models are easy to perform and allow the study of therapeutic agents but do not represent the usual clinical setting. Additionally, biomaterials can be filled into drill hole defects for analysis. Complete osteotomy models are most commonly used and are best suited for the investigation of therapeutic drugs or noninvasive interventions. The metaphyseal defect models allow the study of biomaterials, which are associated with complex and comminuted osteoporotic fractures. CONCLUSION: For a clinically relevant model, we propose that an animal model should satisfy the following criteria to study osteoporotic fracture healing: 1) induction of osteoporosis, 2) complete osteotomy or defect at the metaphysis unilaterally, and 3) internal fixation.Cite this article: R. M. Y. Wong, M. H. V. Choy, M. C. M. Li, K-S. Leung, S. K-H. Chow, W-H. Cheung, J. C. Y. Cheng. A systematic review of current osteoporotic metaphyseal fracture animal models. Bone Joint Res 2018;7:6-11. DOI: 10.1302/2046-3758.71.BJR-2016-0334.R2.

10.
Diabet Med ; 35(3): 360-367, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29055156

RESUMO

AIMS: The comparative efficacy of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy on Type 2 diabetes remission and the role of weight loss are unclear. The DiaRem diabetes remission prediction score uses HbA1c , age and diabetes medications but not diabetes duration. The aim of this study was to compare the DiaRem with the DiaBetter score that includes diabetes duration, upon combined (complete plus partial) 2-year post-surgery diabetes remission in people following RYGB and sleeve gastrectomy, and to investigate the relationship between weight loss and diabetes remission. METHODS: A retrospective single-centre cohort study of obese people with diabetes who underwent RYGB (107) or sleeve gastrectomy (103) and a validation cohort study (173) were undertaken. Diabetes remission, % weight loss, DiaRem, DiaBetter scores and areas under receiving operator characteristic (ROC) curves were calculated. The relationship between % weight loss and diabetes remission was investigated using logistic regression. RESULTS: The proportion of people achieving diabetes remission was highest for those with the lowest DiaBetter and DiaRem scores. Areas under the ROC curves were comparable [DiaBetter: 0.867 (95%CI: 0.817-0.916); DiaRem: 0.865 (95%CI: 0.814-0.915), P=0.856]. Two-year % weight loss was higher post RYGB [26.6 (95%CI: 24.8-28.4)] vs post-sleeve gastrectomy [20.6 (95%CI: 18.3-22.8), P<0.001]. RYGB had 151% higher odds of diabetes remission [OR 2.51 (95%CI: 1.12-5.60), P=0.025]. This association became non-significant when adjusted for % weight loss. CONCLUSION: DiaBetter and DiaRem scores predict diabetes remission following both procedures. Two-year % weight loss plays a key role in determining diabetes remission.


Assuntos
Cirurgia Bariátrica/métodos , Diabetes Mellitus Tipo 2/cirurgia , Gastrectomia/métodos , Redução de Peso/fisiologia , Diabetes Mellitus Tipo 2/sangue , Feminino , Derivação Gástrica/métodos , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Indução de Remissão , Resultado do Tratamento
12.
Eur Cell Mater ; 34: 108-127, 2017 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-28880360

RESUMO

This systematic review examines the efficacy and safety of whole body vibration (WBV) on fracture healing. A systematic literature search was conducted with relevant keywords in PubMed and Embase, independently, by two reviewers. Original animal and clinical studies about WBV effects on fracture healing with available full-text and written in English were included. Information was extracted from the included studies for review. In total, 19 articles about pre-clinical studies were selected. Various vibration regimes are reported; of those, the frequencies of 35 Hz and 50 Hz show better results than others. Most of the studies show positive effects on fracture healing after vibration treatment and the responses to vibration are better in ovariectomised (OVX) animals than non-OVX ones. However, several studies provide insufficient evidence to support an improvement of fracture healing after vibration and one study even reports disruption of fracture healing after vibration. In three studies, vibration results in positive effects on angiogenesis at the fracture site and surrounding muscles during fracture healing. No serious complications or side effects of vibration are found in these studies. WBV is suggested to be beneficial in improving fracture healing in animals without safety problem reported. In order to apply vibration on fractured patients, more well-designed randomised controlled clinical trials are needed to examine its efficacy, regimes and safety.


Assuntos
Consolidação da Fratura , Vibração , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Estrogênios/farmacologia , Consolidação da Fratura/efeitos dos fármacos , Consolidação da Fratura/genética , Consolidação da Fratura/efeitos da radiação , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/genética , Resultado do Tratamento , Vibração/efeitos adversos
13.
Hong Kong Med J ; 23(3): 264-71, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28473651

RESUMO

INTRODUCTION: In setting up a disease registry for fragility fractures in Hong Kong, we conducted a retrospective systematic study on the management of fragility hip fractures. Patient outcomes were compared with the standards from our orthopaedic working group and those from the British Orthopaedic Association that runs a mature fracture registry in the United Kingdom. METHODS: Clinical data on fragility hip fracture patients admitted to six acute major hospitals in Hong Kong in 2012 were captured. These included demographics, pre- and post-operative assessments, discharge details, complications, and 1-year follow-up information. Analysis was performed according to the local standards with reference to those from the British Orthopaedic Association. RESULTS: Overall, 91.0% of patients received orthopaedic care within 4 hours of admission and 60.5% received surgery within 48 hours. Preoperative geri-orthopaedic co-management was received by 3.5% of patients and was one of the reasons for the delayed surgery in 22% of patients. Only 22.9% were discharged with medication that would promote bone health. Institutionalisation on discharge significantly increased by 16.2% (P<0.001). Only 35.1% of patients attended out-patient follow-up 1 year following fracture, and mobility had deteriorated in 69.9% compared with the premorbid state. Death occurred in 17.3% of patients within a year of surgery compared with 1.6% mortality rate in a Hong Kong age-matched population. CONCLUSIONS: The efficiency and quality of acute care for fragility hip fracture patients was documented. Regular geri-orthopaedic co-management can enhance acute care. Much effort is needed to improve functional recovery, prescription of bone health medications, attendance for follow-up, and to decrease institutionalisation. A Fracture Liaison Service is vital to improve long-term care and prevent secondary fractures.


Assuntos
Fraturas do Quadril/cirurgia , Procedimentos Ortopédicos/métodos , Qualidade da Assistência à Saúde , Sistema de Registros , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Fraturas do Quadril/mortalidade , Fraturas do Quadril/patologia , Hong Kong , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos
14.
Environ Technol ; 38(13-14): 1638-1643, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27636360

RESUMO

Dry and chemical torrefaction of sugar cane bagasse was examined in this study with the aim of stabilising and upgrading the fuel properties of bagasse. Dry torrefaction was conducted at temperatures from 160°C to 300°C under inert conditions, whilst chemical torrefaction incorporated a H2SO4 pre-treatment of bagasse. Chemical torrefaction imparted superior chemical and physical properties inducing morphological transformation and textural development with the potential to address issues in handling, feeding and processing bagasse. It increased the energy density of the chars with maximum HHVmass 21.5 MJ/kg and maximum HHVvolume of 7.4 GJ/m3. Chemically torrefied bagasse demonstrated resistance against microbiological attack for 18 months. These features demonstrate the practical value of chemical torrefaction in advancing the utilisation of bagasse as fuel.


Assuntos
Biocombustíveis , Celulose/química , Saccharum , Conservação de Recursos Energéticos , Temperatura Alta , Ácidos Sulfúricos/química
15.
Bioresour Technol ; 223: 202-209, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27792930

RESUMO

This study compared the upgrading of sugar bagasse by thermochemical and dry torrefaction methods and their corresponding combustion behavior relative to raw bagasse. The combustion reactivities were examined by non-isothermal thermogravimetric analysis. Thermochemical torrefaction was carried out by chemical pre-treatment of bagasse with acid followed by heating at 160-300°C in nitrogen environment, while dry torrefaction followed the same heating treatment without the chemical pretreatment. The results showed thermochemical torrefaction generated chars with combustion properties that are closer to various ranks of coal, thus making it more suitable for co-firing applications. Thermochemical torrefaction also induced greater densification of bagasse with a 335% rise in bulk density to 340kg/m3, increased HHVmass and HHVvolume, greater charring and aromatization and storage stability. These features demonstrate the potential of thermochemical torrefaction in addressing the practical challenges in using biomass such as bagasse as fuel.


Assuntos
Biomassa , Celulose/química , Temperatura Alta , Saccharum/química , Biocombustíveis , Carvão Mineral , Dessecação , Incineração
16.
Eur Cell Mater ; 31: 341-54, 2016 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-27215741

RESUMO

Low-magnitude high-frequency vibration (LMHFV) has been proven to promote osteoporotic fracture healing. Mechanical stimulation was reported to enhance SDF-1/CXCR4 signalling in mesenchymal stem cells (MSCs). We hypothesised that LMHFV promoted osteoporotic fracture healing by enhancing MSC migration through the SDF-1/CXCR4 pathway. 152 ovariectomised SD-rats received closed femoral fracture in groups of vibration+MSC (VMG) (20 min/d, 5 d/week), vibration+MSC+AMD3100 (VMAG; AMD, a CXCR4 inhibitor) (1 mg/kg/d, intraperitoneal), MSC (MG) (1 × 106 MSC, intracardiac) or control (CG) for a treatment duration of 2, 4 or 8 weeks. MSC migration was evaluated by ex-vivo green fluorescent protein signal in the callus; and fracture healing was examined by weekly radiographs, endpoint computed-tomography and mechanical test. At week-2 and week-4, ex-vivo callus GFP intensity of VMG was significantly higher than other groups (p < 0.05). From week-2 to week-3, both callus width and callus area in VMG were significantly larger; and from week-7 to week-8, smaller than other groups (p < 0.05). At week-8, high-density bone volume fraction, bone volume fraction, bone mineral density and stiffness in VMG were significantly higher than other 3 groups (p < 0.05). This study demonstrated that LMHFV promoted MSC migration and fracture healing in osteoporotic rats. This effect was attenuated by CXCR4 inhibitor, providing strong evidence that SDF-1-mediated MSC migration was one of the important mechanisms through which LMHFV enhanced fracture healing.


Assuntos
Quimiocina CXCL12/metabolismo , Consolidação da Fratura , Células-Tronco Mesenquimais/citologia , Fraturas por Osteoporose/patologia , Fraturas por Osteoporose/terapia , Receptores CXCR4/metabolismo , Transdução de Sinais , Vibração , Animais , Calo Ósseo/patologia , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica , Teste de Materiais , Fraturas por Osteoporose/diagnóstico por imagem , Ratos Sprague-Dawley , Microtomografia por Raio-X
17.
Osteoporos Int ; 27(10): 2989-3000, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27155884

RESUMO

UNLABELLED: Estrogen receptor (ER) in ovariectomy-induced osteoporotic fracture was reported to exhibit delayed expression. Mechanical stimulation enhanced ER-α expression in osteoporotic fracture callus at the tissue level. ER was also found to be required for the effectiveness of vibrational mechanical stimulation treatment in osteoporotic fracture healing. INTRODUCTION: Estrogen receptor(ER) is involved in mechanical signal transduction in bone metabolism. Its expression was reported to be delayed in osteoporotic fracture healing. The purpose of this study was to investigate the roles played by ER during osteoporotic fracture healing enhanced with mechanical stimulation. METHODS: Ovariectomy-induced osteoporotic SD rats that received closed femoral fractures were divided into five groups, (i) SHAM, (ii) SHAM-VT, (iii) OVX, (iv) OVX-VT, and (v) OVX-VT-ICI, where VT stands for whole-body vibration treatment and ICI for ER antagonization by ICI 182,780. Callus formation and gene expression were assessed at 2, 4, and 8 weeks postfracture. In vitro osteoblastic differentiation, mineralization, and ER-α expression were assessed. RESULTS: The delayed ER expression was found to be enhanced by vibration treatment. Callus formation enhancement was shown by callus morphometry and micro-CT analysis. Enhancement effects by vibration were partially abolished when ER was modulated by ICI 182,780, in terms of callus formation capacity at 2-4 weeks and ER gene and protein expression at all time points. In vitro, ER expression in osteoblasts was not enhanced by VT treatment, but osteoblastic differentiation and mineralization were enhanced under estrogen-deprived condition. When osteoblastic cells were modulated by ICI 182,780, enhancement effects of VT were eliminated. CONCLUSIONS: Vibration was able to enhance ER expression in ovariectomy-induced osteoporotic fracture healing. ER was essential in mechanical signal transduction and enhancement in callus formation effects during osteoporotic fracture healing enhanced by vibration. The enhancement of ER-α expression by mechanical stimulation was not likely to be related to the increased expression in osteoblastic cells but rather to the systemic enhancement in recruitment of ER-expressing progenitor cells through increased blood flow and neo-angiogenesis. This finding might explain the observed difference in mechanical sensitivity of osteoporotic fracture to mechanical stimulation.


Assuntos
Calo Ósseo/metabolismo , Consolidação da Fratura , Fraturas por Osteoporose/terapia , Receptores de Estrogênio/metabolismo , Vibração , Animais , Calo Ósseo/patologia , Feminino , Mecanotransdução Celular , Fraturas por Osteoporose/patologia , Ovariectomia , Ratos , Ratos Sprague-Dawley
18.
J Musculoskelet Neuronal Interact ; 16(1): 4-11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26944817

RESUMO

OBJECTIVES: To investigate the effects on muscle performance after one-year cessation of 18-month low-magnitude high-frequency vibration (LMHFV) intervention in the untrained community elderly. METHODS: This is a case-control study with 59 community elderly women (25 control without any treatment; 34 received 18-month LMHFV but discontinued for 1 year from our previous clinical study). Muscle strength, balancing ability, occurrence of fall/fracture, quality of life (QoL) were assessed 1-year after cessation of intervention. The 30-month results were compared with baseline and 18-month treatment endpoint data between groups. RESULTS: At 30 months (i.e. one year post-intervention), the muscle strengths of dominant and non-dominant legs relative to baseline in treatment group were significantly better than those of control. In balancing ability test, reaction time, movement velocity and maximum excursion of treatment group (relative to baseline) remained significantly better than the control group. The muscle strength, balancing ability and quality of life at 30 months relative to 18 months did not show significant differences between the two groups. CONCLUSION: The benefits of LMHFV for balancing ability, muscle strength and risk of falling in elderly were retained 1 year after cessation of LMHFV.


Assuntos
Acidentes por Quedas/prevenção & controle , Força Muscular/fisiologia , Equilíbrio Postural/fisiologia , Qualidade de Vida , Vibração/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos
19.
J Musculoskelet Neuronal Interact ; 15(4): 316-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26636277

RESUMO

OBJECTIVES: Low-magnitude high-frequency vibration (LMHFV) was reported beneficial to muscle contractile functions in clinical and preclinical studies. This study aims to investigate the effects of LMHFV on myofibers, myogenic cells and functional properties of disused soleus (Sol) and gastrocnemius medialis (GM) during reloading. METHODS: Sprague Dawley rats were hind-limb unloaded for 28 days and assigned to reloading control (Ctrl) or LMHFV group (Vib). Sol and GM of both groups were harvested for fiber typing, proliferating myogenic cell counting and in vitro functional assessment. RESULTS: Myogenic cells proliferation was promoted by LMHFV in both Sol and GM (p<0.001 and p<0.05 respectively). Force generating capacity was not much affected (Vib=Ctrl, p>0.05) but fast-fiber favorable changes in fiber type switching (more type IIA but lower type I in Vib; p<0.05 and 0.01 respectively) and fiber hypertrophy (type I, Vib

Assuntos
Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Lenta/patologia , Músculo Esquelético/patologia , Vibração , Animais , Contagem de Células , Elevação dos Membros Posteriores/efeitos adversos , Imuno-Histoquímica , Masculino , Células Musculares/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/fisiopatologia , Ratos , Ratos Sprague-Dawley
20.
J Obes ; 2015: 693829, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26199740

RESUMO

BACKGROUND: Lifestyle intervention programs after bariatric surgery have been suggested to maximise health outcomes. This pilot study aimed to investigate the feasibility and impact of an 8-week combined supervised exercise with nutritional-behavioral intervention following Roux-en-Y gastric bypass and sleeve gastrectomy. METHODS: Eight female patients (44 ± 8 years old, BMI = 38.5 ± 7.2 kg m(-2)) completed the program. Before and after intervention, anthropometric measures, six-minute walk test (6MWT), physical activity level, eating behavior, and quality of life (QoL) were assessed. Percentage weight loss (%WL) outcomes were compared with a historical matched control group. RESULTS: The program significantly improved functional capacity (mean increment in 6MWT was 127 ± 107 meters, p = 0.043), increased strenuous intensity exercise (44 ± 49 min/week, p = 0.043), increased consumption of fruits and vegetables (p = 0.034), reduced consumption of ready meals (p = 0.034), and improved "Change in Health" in QoL domain (p = 0.039). The intervention group exhibited greater %WL in the 3-12-month postsurgery period compared to historical controls, 12.2 ± 7.5% versus 5.1 ± 5.4%, respectively (p = 0.027). CONCLUSIONS: Lifestyle intervention program following bariatric surgery is feasible and resulted in several beneficial outcomes. A large randomised control trial is now warranted.


Assuntos
Terapia Comportamental/métodos , Exercício Físico , Gastrectomia , Derivação Gástrica , Terapia Nutricional/métodos , Obesidade Mórbida/terapia , Redução de Peso , Adulto , Terapia Combinada , Estudos de Viabilidade , Feminino , Humanos , Obesidade Mórbida/prevenção & controle , Obesidade Mórbida/psicologia , Projetos Piloto , Qualidade de Vida , Comportamento de Redução do Risco , Resultado do Tratamento
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