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1.
Naunyn Schmiedebergs Arch Pharmacol ; 396(12): 3695-3705, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37306713

RESUMO

Lappaconitine (LA), a diterpenoid alkaloid extracted from the root of Aconitum sinomontanum Nakai, exhibits broad pharmacological effects, including anti-tumor activity. The inhibitory effect of lappaconitine hydrochloride (LH) on HepG2 and HCT-116 cells and the toxicity of lappaconitine sulfate (LS) on HT-29, A549, and HepG2 cells have been described. But the mechanisms of LA against human cervical cancer HeLa cells still need to be clarified. This study was designed to investigate the effects and molecular mechanisms of lappaconitine sulfate (LS) on the growth inhibition and apoptosis in HeLa cells. The cell viability and proliferation were evaluated using the Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2´-deoxyuridine (EdU) assay, respectively. The cell cycle distribution and apoptosis were detected by flow cytometry analysis and 4', 6-diamidino-2-phenylindole (DAPI) staining. The mitochondrial membrane potential (MMP) was determined through the 5, 5', 6, 6'-tetrachloro-1, 1', 3, 3'-tetraethylbenzimi-dazolyl carbocyanine iodide (JC-1) staining. The cell cycle arrest-, apoptosis-, and the phosphatidylinositol-3-kinase/protein kinase B/glycogen synthase kinase 3ß (PI3K/AKT/GSK3ß) pathway-related proteins were estimated by western blot analysis. LS markedly reduced the viability and suppressed the proliferation of HeLa cells. LS induced G0/G1 cell cycle arrest through the inhibition of Cyclin D1, p-Rb, and induction of p21 and p53. Furthermore, LS triggered apoptosis through the activation of mitochondrial-mediated pathway based on decrease of Bcl-2/Bax ratio and MMP and activation of caspase-9/7/3. Additionally, LS led to constitutive downregulation of the PI3K/AKT/GSK3ß signaling pathway. Collectively, LS inhibited cell proliferation and induced apoptosis through mitochondrial-mediated pathway by suppression of the PI3K/AKT/GSK3ß signaling pathway in HeLa cells.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Células HeLa , Glicogênio Sintase Quinase 3 beta/metabolismo , Sulfatos/farmacologia , Transdução de Sinais , Apoptose , Proliferação de Células , Linhagem Celular Tumoral
2.
Life (Basel) ; 13(6)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37374160

RESUMO

Bone mechanics is well understood at every length scale except the nano-level. We aimed to investigate the relationship between bone nanoscale and tissue-level mechanics experimentally. We tested two hypotheses: (1) nanoscale strains were lower in hip fracture patients versus controls, and (2) nanoscale mineral and fibril strains were inversely correlated with aging and fracture. A cross-sectional sample of trabecular bone sections was prepared from the proximal femora of two human donor groups (aged 44-94 years): an aging non-fracture control group (n = 17) and a hip-fracture group (n = 20). Tissue, fibril, and mineral strain were measured simultaneously using synchrotron X-ray diffraction during tensile load to failure, then compared between groups using unpaired t-tests and correlated with age using Pearson's correlation. Controls exhibited significantly greater peak tissue, mineral, and fibril strains than the hip fracture (all p < 0.05). Age was associated with a decrease in peak tissue (p = 0.099) and mineral (p = 0.004) strain, but not fibril strain (p = 0.260). Overall, hip fracture and aging were associated with changes in the nanoscale strain that are reflected at the tissue level. Data must be interpreted within the limitations of the observational cross-sectional study design, so we propose two new hypotheses on the importance of nanomechanics. (1) Hip fracture risk is increased by low tissue strain, which can be caused by low collagen or mineral strain. (2) Age-related loss of tissue strain is dependent on the loss of mineral but not fibril strain. Novel insights into bone nano- and tissue-level mechanics could provide a platform for the development of bone health diagnostics and interventions based on failure mechanisms from the nanoscale up.

3.
Sci Rep ; 10(1): 14208, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848149

RESUMO

Nanoscale mineralized collagen fibrils may be important determinants of whole-bone mechanical properties and contribute to the risk of age-related fractures. In a cross-sectional study nano- and tissue-level mechanics were compared across trabecular sections from the proximal femora of three groups (n = 10 each): ageing non-fractured donors (Controls); untreated fracture patients (Fx-Untreated); bisphosphonate-treated fracture patients (Fx-BisTreated). Collagen fibril, mineral and tissue mechanics were measured using synchrotron X-Ray diffraction of bone sections under load. Mechanical data were compared across groups, and tissue-level data were regressed against nano. Compared to controls fracture patients exhibited significantly lower critical tissue strain, max strain and normalized strength, with lower peak fibril and mineral strain. Bisphosphonate-treated exhibited the lowest properties. In all three groups, peak mineral strain coincided with maximum tissue strength (i.e. ultimate stress), whilst peak fibril strain occurred afterwards (i.e. higher tissue strain). Tissue strain and strength were positively and strongly correlated with peak fibril and mineral strains. Age-related fractures were associated with lower peak fibril and mineral strain irrespective of treatment. Indicating earlier mineral disengagement and the subsequent onset of fibril sliding is one of the key mechanisms leading to fracture. Treatments for fragility should target collagen-mineral interactions to restore nano-scale strain to that of healthy bone.


Assuntos
Envelhecimento/fisiologia , Osso e Ossos/fisiologia , Colágenos Fibrilares/fisiologia , Fraturas do Quadril/etiologia , Osteoporose/complicações , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Nanoestruturas , Osteoporose/fisiopatologia
4.
J Mech Behav Biomed Mater ; 109: 103838, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32543404

RESUMO

The fracture resistance of load-bearing trabecular bone is adversely affected by diseases such as osteoporosis. However, there are few published measurements of trabecular bone fracture toughness due to the difficulty of conducting reliable tests in small specimens of this highly porous material. A new approach is demonstrated that uses digital volume correlation of X-ray computed tomographs to measure 3D displacement fields in which the crack shape and size can be objectively identified using a phase congruency analysis. The criteria for crack propagation, i.e. fracture toughness, can then be derived by finite element simulation, with knowledge of the elastic properties.


Assuntos
Fraturas Ósseas , Osteoporose , Osso Esponjoso/diagnóstico por imagem , Análise de Elementos Finitos , Fraturas Ósseas/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X
5.
Geriatr Orthop Surg Rehabil ; 11: 2151459319897520, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31976153

RESUMO

INTRODUCTION: Direct oral anticoagulants (DOACs) decrease the risk of venous thromboembolism (VTE) without increasing the risk of hemorrhage in elective lower limb orthopedic surgery. However, the role of DOACs in preventing VTE following hip fracture surgery in the older adults remains unclear. This study aims to evaluate the efficacy and safety of DOACs in older adults undergoing surgery for hip fracture. MATERIALS AND METHODS: Single-center, retrospective, population-based cohort study of patients receiving either a DOAC or low-molecular-weight heparin (LMWH) for VTE prophylaxis following hip fracture surgery. Data obtained included patient demographics, comorbidities, fracture classification, time to surgery, procedure performed, and length of stay. Main outcomes assessed were incidence of VTE, incidence of major hemorrhage, and death within 30 days of surgery. RESULTS: A total of 321 patients were included. Incidence of VTE was 0% in the DOAC group and 3.4% in the LMWH group (risk ratio [RR]:0.26, 95% confidence interval [CI]: 0.02-4.34, P = .35). Hemorrhage occurred in 7.4% and 3.0% of patients in the DOAC and LMWH groups, respectively (RR: 2.47, 95% CI: 0.77-7.91, P = .13). Mortality from VTE was 0% in the DOAC group and 0.7% in the LMWH group (RR: 0.97, 95% CI: 0.05-20.02, P = .99). Mortality from hemorrhage was 1.9% in the DOAC group and 0.7% in the LMWH group (RR: 2.47, 95% CI: 0.23-26.78, P = .46). DISCUSSION: The use of DOACs for VTE prophylaxis following surgery in older adults with hip fracture was associated with a similar rate of VTE compared to LMWH. However, there was a worrying trend toward an increased risk of hemorrhage. CONCLUSION: In the present study of a carefully selected cohort of patients, the effect of DOACs in reducing the risk of VTE following surgery for hip fracture in the older adults was comparable to LMWH. However, a trend toward increased risk of hemorrhage was noted. Larger prospective studies will be required to identify patients who will benefit the most from treatment.

6.
Orthop Res Rev ; 11: 79-92, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496838

RESUMO

INTRODUCTION: Knee osteoarthritis is a major cause of pain and disability for which joint distraction is a potential treatment to delay the need for knee arthroplasty. This systematic review aims to assess the short- and long-term clinical and structural outcomes following knee joint distraction (KJD). METHODS: MEDLINE, EMBASE, Scopus, and Web of Science databases were searched from the date of inception to 26th June 2019. Clinical studies investigating joint distraction for knee osteoarthritis with outcomes including ∆WOMAC index, ∆VAS pain score, and ∆joint space width were included. The review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) - CRD42018087032. RESULTS: Nine studies comprising a total of 507 patients were included. There were four randomized controlled trials (RCTs), five open prospective cohort studies, and one case series. Overall, there were significant improvements in WOMAC index, VAS pain score and joint space width following KJD, which persisted up to 9 years. KJD also demonstrated comparable clinical outcomes with high tibial osteotomy and total knee arthroplasty. CONCLUSION: There is moderate quality evidence supporting the beneficial outcomes of joint distraction for knee osteoarthritis. Larger RCTs with longer follow-up (>1 year) are necessary to establish the true effect size of this procedure.

7.
Sci Rep ; 9(1): 7416, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31092837

RESUMO

The cortex of the femoral neck is a key structural element of the human body, yet there is not a reliable metric for predicting the mechanical properties of the bone in this critical region. This study explored the use of a range of non-destructive metrics to measure femoral neck cortical bone stiffness at the millimetre length scale. A range of testing methods and imaging techniques were assessed for their ability to measure or predict the mechanical properties of cortical bone samples obtained from the femoral neck of hip replacement patients. Techniques that can potentially be applied in vivo to measure bone stiffness, including computed tomography (CT), bulk wave ultrasound (BWUS) and indentation, were compared against in vitro techniques, including compression testing, density measurements and resonant ultrasound spectroscopy. Porosity, as measured by micro-CT, correlated with femoral neck cortical bone's elastic modulus and ultimate compressive strength at the millimetre length scale. Large-tip spherical indentation also correlated with bone mechanical properties at this length scale but to a lesser extent. As the elastic mechanical properties of cortical bone correlated with porosity, we would recommend further development of technologies that can safely measure cortical porosity in vivo.


Assuntos
Osso Cortical/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Força Compressiva , Osso Cortical/fisiologia , Osso Cortical/ultraestrutura , Feminino , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/fisiologia , Colo do Fêmur/ultraestrutura , Humanos , Masculino , Pessoa de Meia-Idade , Porosidade , Tomografia Computadorizada por Raios X , Microtomografia por Raio-X
8.
Injury ; 50(2): 534-540, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30466734

RESUMO

INTRODUCTION: Acute lateral patellar dislocation is a very common condition in orthopedics, especially among adolescents and physically active patients. To evaluate distinct medial patellofemoral ligament (MPFL) injury patterns and the associated knee pathology after acute lateral patellar dislocation (ALPD) using magnetic resonance imaging (MRI) studies, which is essential for the development of treatment protocols. MATERIALS AND METHODS: MRI images of 74 ALPD patients were taken between January 2015 to December 2016. Images were evaluated using standardized protocols. RESULTS: The prevalence of MPFL injury following ALPD was 97.3% (72/74 patients). Among the 72 patients with MPFL, the prevalence of Type Ⅰ injury was 26.4% (19/72). Since only bone marrow edema and a partial tear were showed on MRI of these patients, conservative treatment was given. Tear of the MPFL occurred at the patellar attachment (Type Ⅱa) in 16 patients (16/72, 22.2%), at the middle area of the ligament (Type Ⅱb) in 5 patients (5/72, 6.9%), and at the femoral attachment (Type Ⅱc) in 27 patients (27/72, 37.5%). For Type Ⅱ injuries, all patients had the surgery to reconstruct the MPFL. The prevalence of Type Ⅲ MPFL injury was 6.9% (5/72) after the surgery. CONCLUSION: MPFL injury of is a common sequel following ALPD. We assessed the distinct injury pattern and associated pathology of MPFL using MRI studies. A good understanding of the injury pattern and associated knee pathology of MPFL is essential in managing patients with ALPD, especially if surgical intervention is considered.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Instabilidade Articular/diagnóstico por imagem , Ligamentos Articulares/diagnóstico por imagem , Imageamento por Ressonância Magnética , Luxação Patelar/classificação , Articulação Patelofemoral/lesões , Adolescente , Cartilagem Articular/lesões , Criança , China/epidemiologia , Feminino , Humanos , Ligamentos Articulares/lesões , Masculino , Luxação Patelar/diagnóstico por imagem , Luxação Patelar/epidemiologia , Luxação Patelar/patologia , Articulação Patelofemoral/diagnóstico por imagem , Articulação Patelofemoral/fisiopatologia , Prevalência , Estudos Prospectivos , Adulto Jovem
9.
SICOT J ; 4: 58, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30560779

RESUMO

INTRODUCTION: Minimally invasive percutaneous plate osteosynthesis (MIPPO) has emerged as a viable alternative for the treatment of distal tibial fractures. However, the clinical outcomes of this procedure compared to intramedullary (IM) nail fixation have yet to be established. The present meta-analysis aims to compare the clinical outcomes following MIPPO and IM nail fixation for closed distal tibial fractures. METHODS: MEDLINE and EMBASE databases were searched from date of inception to 10th April 2017. Randomized controlled trials (RCTs) comparing MIPPO with IM nail fixation for closed and Gustilo Grade I distal tibial fractures were included. Outcomes assessed included time to union, complications and functional outcomes. Quality and risk of bias of the RCTs were assessed using the Cochrane Collaboration Tool. RESULTS: Five RCTs comprising 497 patients were included. MIPPO was associated with a longer time to union (MD: 1.08, 95% CI: 0.26, 1.90, p = 0.010, I 2 = 84%) and increased risk of wound complications (RR: 1.58, 95% CI: 1.01, 2.46, p = 0.04, I 2 = 0%). Both MIPPO and IM nail fixation had comparable risks of malunion, delayed union, non-union and deep infections, with similar functional outcomes. DISCUSSION: Compared to IM nail fixation, a MIPPO fixation technique for distal tibial fractures is associated with a longer time to fracture union and an increased risk of wound complications. Neither technique demonstrates a clear advantage with regard to risk of malunion/non-union, or functional outcome. Assuming equivalent surgical expertise with both techniques, the results suggest that IM nail fixation is the treatment modality of choice for these challenging fractures.

10.
Open Access Rheumatol ; 10: 135-140, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30323693

RESUMO

Osteoarthritis is the most prevalent chronic joint condition worldwide. The principles of osteoarthritis treatment are to alleviate pain and stiffness as well as maintain function, with current consensus guidelines recommending the use of a combination of conservative measures including physical therapy, analgesia, and surgical interventions such as arthroplasty. In recent years, several pharmacological therapies have emerged as potential alternatives. Although a disease-modifying osteoarthritis drug has yet to be identified, promising results have been reported in recent trials especially with serotonin-norepinephrine reuptake inhibitors, IL-1 antagonists, and antibodies to nerve growth factor. The present review aims to summarize and discuss the latest results of novel treatments for osteoarthritis and potential targets for future research.

11.
Syst Rev ; 7(1): 162, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30322405

RESUMO

BACKGROUND: Osteoarthritis is a degenerative joint disease that is highly prevalent worldwide. Knee osteoarthritis is the most common form of osteoarthritis and is a major cause of pain and disability. However, there remains a lack of treatments available that have demonstrated effectiveness in stopping or reversing the degenerative process. Joint distraction has emerged as a viable alternative in the treatment of knee osteoarthritis to delay the need for knee arthroplasty. METHODS: An electronic search will be conducted on MEDLINE, EMBASE, Web of Science, CINAHL, Cochrane and EBSCO databases. Clinical studies investigating joint distraction for knee osteoarthritis, which reported clinical or structural outcomes including ∆WOMAC index, ∆VAS pain score and ∆joint space width will be included. Risk of bias will be assessed using the Newcastle-Ottawa Scale for observational studies and Cochrane Collaboration tool for randomised controlled trials. Quality of studies will be assessed using the modified Coleman methodology score. DISCUSSION: This systematic review will summarise the short- and long-term clinical and structural outcomes following joint distraction for knee osteoarthritis. The findings from this review will establish the quality of currently available evidence, which will determine the need for further studies to establish the true effect size of this procedure. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018087032.


Assuntos
Procedimentos Ortopédicos , Osteoartrite do Joelho/cirurgia , Humanos , Metanálise como Assunto , Projetos de Pesquisa , Índice de Gravidade de Doença , Revisões Sistemáticas como Assunto , Fatores de Tempo , Resultado do Tratamento
12.
PLoS One ; 13(7): e0200475, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30001364

RESUMO

OBJECTIVES: Bone material properties are a major determinant of bone health in older age, both in terms of fracture risk and implant fixation, in orthopaedics and dentistry. Bone is an anisotropic and hierarchical material so its measured material properties depend upon the scale of metric used. The scale used should reflect the clinical problem, whether it is fracture risk, a whole bone problem, or implant stability, at the millimetre-scale. Indentation, an engineering technique involving pressing a hard-tipped material into another material with a known force, may be able to assess bone stiffness at the millimetre-scale (the apparent elastic modulus). We aimed to investigate whether spherical-tip indentation could reliably measure the apparent elastic modulus of human cortical bone. MATERIALS AND METHODS: Cortical bone samples were retrieved from the femoral necks of nineteen patients undergoing total hip replacement surgery (10 females, 9 males, mean age: 69 years). The samples underwent indentation using a 1.5 mm diameter, ruby, spherical indenter tip, with sixty indentations per patient sample, across six locations on the bone surfaces, with ten repeated indentations at each of the six locations. The samples then underwent mechanical compression testing. The repeatability of indentation measurements of elastic modulus was assessed using the co-efficient of repeatability and the correlation between the bone elastic modulus measured by indentation and compression testing was analysed by least-squares regression. RESULTS: In total, 1140 indentations in total were performed. Indentation was found to be repeatable for indentations performed at the same locations on the bone samples with a mean co-efficient of repeatability of 0.4 GigaPascals (GPa), confidence interval (C.I): 0.33-0.42 GPa. There was variation in the indentation modulus results between different locations on the bone samples (mean co-efficient of repeatability: 3.1 GPa, C.I: 2.2-3.90 GPa). No clear correlation was observed between indentation and compression values of bone elastic modulus (r = 0.33, p = 0.17). The mean apparent elastic modulus obtained by spherical indentation was 9.9 GPa, the standard deviation for each indent cycle was 0.11 GPa, and the standard deviation between locations on the same sample was 1.01 GPa. The mean compression apparent elastic modulus was 4.42 GPa, standard deviation 1.02 GPa. DISCUSSION: Spherical-tip indentation was found to be a repeatable test for measuring the elastic modulus of human cortical bone, demonstrated by a low co-efficient of repeatability in this study. It could not, however, reliably predict cortical bone elastic modulus determined by platens compression testing in this study. This may be due to indentation only probing mechanical properties at the micro-scale while platens compression testing assesses millimetre length-scale properties. Improvements to the testing technique, including the use of a larger diameter spherical indenter tip, may improve the measurement of bone stiffness at the millimetre scale and should be investigated further.


Assuntos
Densidade Óssea , Osso Cortical/química , Cabeça do Fêmur/química , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Int J Surg ; 50: 35-42, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29284151

RESUMO

BACKGROUND: In patients with hepatocellular carcinoma (HCC) and cirrhosis, laparoscopic hepatectomy (LH) confers short-term benefits over open hepatectomy (OH) but the long-term outcomes of this procedure are unclear. This systematic review aims to compare the long-term survival outcomes of LH and OH for patients with HCC and underlying cirrhosis. METHODS: EMBASE, MEDLINE and Scopus databases were searched from date of inception to 7th October 2016. Controlled clinical studies comparing LH to OH for HCC in cirrhotic patients, which reported long-term overall and disease-free survival were included. The studies were evaluated using the MOOSE guidelines and Newcastle-Ottawa Scale. Data were extracted and analysed using a fixed-effects model. RESULTS: Five non-randomised, retrospective observational studies representing 888 patients were included. LH was associated with significantly lower tumour recurrence [OR: 0.65, 95% CI: 0.48, 0.89]. LH conferred greater overall survival at 1- [HR: 0.41, 95% CI: 0.25, 0.68], 3- [HR: 0.63, 95% CI: 0.46, 0.87] and 5-years [HR: 0.60, 95% CI: 0.45, 0.80]. With LH, there was higher disease-free survival at 1-year [HR: 0.71, 95% CI: 0.53, 0.96], but not at 3- [HR: 0.89, 95% CI: 0.70, 1.14]; and 5-years [HR: 0.85, 95% CI: 0.70, 1.04]. CONCLUSIONS: Laparoscopic surgery is associated with comparable postoperative and survival outcomes in patients with HCC and underlying cirrhosis. With careful selection of patients, this approach is safe, feasible and advantageous.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Laparoscopia/métodos , Cirrose Hepática/complicações , Neoplasias Hepáticas/cirurgia , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/mortalidade , Conversão para Cirurgia Aberta/estatística & dados numéricos , Feminino , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/mortalidade , Masculino , Recidiva Local de Neoplasia/cirurgia , Período Pós-Operatório , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
14.
Sci Rep ; 7: 43399, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28262693

RESUMO

Osteoporosis is characterised by trabecular bone loss resulting from increased osteoclast activation and unbalanced coupling between resorption and formation, which induces a thinning of trabeculae and trabecular perforations. Bisphosphonates are the frontline therapy for osteoporosis, which act by reducing bone remodelling, and are thought to prevent perforations and maintain microstructure. However, bisphosphonates may oversuppress remodelling resulting in accumulation of microcracks. This paper aims to investigate the effect of bisphosphonate treatment on microstructure and mechanical strength. Assessment of microdamage within the trabecular bone core was performed using synchrotron X-ray micro-CT linked to image analysis software. Bone from bisphosphonate-treated fracture patients exhibited fewer perforations but more numerous and larger microcracks than both fracture and non-fracture controls. Furthermore, bisphosphonate-treated bone demonstrated reduced tensile strength and Young's Modulus. These findings suggest that bisphosphonate therapy is effective at reducing perforations but may also cause microcrack accumulation, leading to a loss of microstructural integrity and consequently, reduced mechanical strength.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Osso e Ossos/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Osteoporose/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/lesões , Estudos de Casos e Controles , Módulo de Elasticidade , Feminino , Fraturas Ósseas/patologia , Fraturas Ósseas/cirurgia , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Osteoporose/patologia , Síncrotrons , Resistência à Tração , Microtomografia por Raio-X
15.
Clin Rev Bone Miner Metab ; 14(3): 150-160, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27683260

RESUMO

Bone is a complex hierarchical structure, and its principal function is to resist mechanical forces and fracture. Bone strength depends not only on the quantity of bone tissue but also on the shape and hierarchical structure. The hierarchical levels are interrelated, especially the micro-architecture, collagen and mineral components; hence, analysis of their specific roles in bone strength and stiffness is difficult. Synchrotron imaging technologies including micro-CT and small/wide angle X-ray scattering/diffraction are becoming increasingly popular for studying bone because the images can resolve deformations in the micro-architecture and collagen-mineral matrix under in situ mechanical loading. Synchrotron cannot be directly applied in vivo due to the high radiation dose but will allow researchers to carry out systematic multifaceted studies of bone ex vivo. Identifying characteristics of aging and disease will underpin future efforts to generate novel devices and interventional therapies for assessing and promoting healthy aging. With our own research work as examples, this paper introduces how synchrotron imaging technology can be used with in situ testing in bone research.

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