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1.
Head Face Med ; 16(1): 29, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33213460

RESUMO

BACKGROUND: Periodontal health is of great concern for periodontists and orthodontists in the inter-disciplinary management of patients with bimaxillary protrusion. The aim of present study is to investigate changes in the alveolar bone in the maxillary incisor region and to explore its relationship with displacement of root apex as well as changes in the inclination of maxillary incisors during incisor retraction. METHODS: Samples in this retrospective study consisted of 38 patients with bimaxillary protrusion. Cone-beam computed tomography (CBCT) images was taken before(T0) and after (T1) treatment. Alveolar bone thickness (ABT), height (ABH) and area (ABA) were utilized to evaluate changes in the alveolar bone, while incisor inclination and apex displacement were used to assess changes in the position of maxillary central and lateral incisors. Correlations between alveolar bone remodeling and apex displacement as well as changes in the inclination were investigated. RESULTS: The labial ABT of central and lateral incisors at the mid-root third was increased. In contrast, the palatal ABT at crestal, mid-root and apical third level were consistently decreased. ABH was not altered on the labial side, while significantly decreased on the palatal side. ABA was not significantly increased on the labial side, but significantly decreased on the palatal side, leading to a significantly reduced total ABA. Orthodontic treatment significantly reduced inclination of upper incisors. Changes in the amount (T1-T0) of ABA was remarkably correlated with apex displacement and changes of inclination (T1-T0); in addition, using the multivariate linear regression analysis, changes of ABA on the palatal side (T1-T0) can be described by following equation: Changes of palatal ABA (T1-T0) = - 3.258- 0.139× changes of inclination (T1-T0) + 2.533 × apex displacement (T1-T0). CONCLUSIONS: Retraction of incisors in bimaxillary protrusion patients may compromise periodontal bone support on the palatal side. An equation that incorporated the displacement of root apex and change in the incisor inclination may enable periodontist-orthodontist interdisciplinary coordination in assessing treatment risks and developing an individualized treatment plan for adult patients with bimaxillary protrusion. Moreover, the equation in predicating area of alveolar bone may reduce the risks of placing the teeth out of the bone boundary during 3D digital setups.


Assuntos
Incisivo , Técnicas de Movimentação Dentária , Adulto , Remodelação Óssea , Cefalometria , Tomografia Computadorizada de Feixe Cônico , Humanos , Incisivo/diagnóstico por imagem , Maxila/diagnóstico por imagem , Estudos Retrospectivos
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1618-1624, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067963

RESUMO

OBJECTIVE: To explore the clinical value of serum bone turnover markers including ß-CrossLaps (ß-CTx), N-MID Osteocalcin (Osteocalcin), and total procollagen type 1 amino-terminal propeptide (TP1NP) in patients with myeloma bone disease (MBD). METHODS: A total of 55 MBD patients(MBD group) and 20 healthy volunteers(control group) were selected, and the serum was collected for detecting ß-CTx, Osteocalcin and TP1NP by Roche analyzer of automated electrochemiluminescence. Meanwhile, the imaging techniques such as MRI and CT were used for evaluation of bone destruction and the damage extent in MBD patients. RESULTS: Measurement data is expressed as median (P25, P75) according to distribution characteristics of data. The detection results showed that concentrations of ß-CTx in MBD patients and control group were 0.72(0.48, 1.28) ng/mL and 0.53(0.34, 0.61) ng/mL respectively, the ß-CTx concentration in MBD patients was significantly higher than that in control group(P=0.002). The ratio ß-CTx to TP1NP (%) in MBD patients and control group was 1.50 (1.05, 3.36) and 1.25 (0.86, 1.35) respectively, the ratio in MBD patients was significantly higher than that in control group (P=0.007). The serum ß-CTx concentrations in MBD patients of localized bone destruction type and extensive bone destruction type were 0.41(0.31, 0.66) ng/mL and 1.14(0.72, 1.81) ng/mL respectively, the ß-CTx concentration in MBD patients of extensive bone destruction type was significantly higher than that in MBD patients of localized bone destruction type (P<0.001). The ratio of ß-CTx to TP1NP(%) in MBD patients of localized and extensive bone destruction type was 1.30 (0.90, 2.49) and 1.98 (1.18, 3.76) respectively, the ratio in the MBD patients of extensive bone destruction type was significantly higher than that in MBD patients of localized bone destruction type (P=0.019). The serum osteocalcin concentrations in MBD patients of localized and extensive bone destruction type were 14.31 (8.82, 19.39) ng/mL and 21.52 (14.42, 47.76) ng/mL respectively, the osteocalcin concentration in MBD patients of extensive bone destruction type was higher than that in MBD patients of localized bone destruction type (P=0.008). The AUC of ß-CTx was 0.88 (95% CI: 0.78-0.98)(P<0.001), and the cut-off value was 0.69 ng/ml in the diagnosis of extensive bone injury for MBD patients, and the sensitivity and specificity were 80.65% and 83.33% respectively. CONCLUSION: The MBD patients show bone resorption hyperthyroidism and high bone turnover. The ß-CTx and osteocalcin in serum bone turnover markers can effectively reflect the extent of bone damage in MBD patients, especially the ß-CTx is more efficient for the diagnosis of MBD patients of extensive bone destruction type. However, ß-CTx, osteocalcin and TP1NP are not relate with the MM disease progression.


Assuntos
Doenças Ósseas , Mieloma Múltiplo , Biomarcadores , Remodelação Óssea , Humanos , Osteocalcina
3.
Arch Osteoporos ; 15(1): 143, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929613

RESUMO

INTRODUCTION: Iron overload, a state with excessive iron storage in the body, is a common complication in thalassemia patients which leads to multiple organ dysfunctions including the bone. Iron overload-induced bone disease is one of the most common and severe complications of thalassemia including osteoporosis. Currently, osteoporosis is still frequently found in thalassemia even with widely available iron chelation therapy. STUDY SELECTION: Relevant publications published before December 2019 in PubMed database were reviewed. Both pre-clinical studies and clinical trials were obtained using iron overload, thalassemia, osteoporosis, osteoblast, and osteoclast as keywords. RESULTS: Increased ROS production is a hallmark of iron overload-induced impaired bone remodeling. At the cellular level, oxidative stress affects bone remodeling by both osteoblast inhibition and osteoclast activation via many signaling pathways. In thalassemia patients, it has been shown that bone resorption was increased while bone formation was concurrently reduced. CONCLUSION: In this review, reports on the cellular mechanisms of iron overload-associated bone remodeling are comprehensively summarized and presented to provide current understanding this pathological condition. Moreover, current treatments and potential interventions for attenuating bone remodeling in iron overload are also summarized to pave ways for the future discoveries of novel agents that alleviate this condition.


Assuntos
Remodelação Óssea , Sobrecarga de Ferro/sangue , Osteoporose/etiologia , Talassemia/complicações , Humanos , Osteoclastos
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(9): 617-623, 2020 Sep 09.
Artigo em Chinês | MEDLINE | ID: mdl-32878395

RESUMO

Objective: To establish a three-dimensional (3D) quantitative measurement and evaluate the condylar bone remodeling of temporomandibular joint (TMJ). Methods: Pre-and post-treatment cone-beam CT (CBCT) data were obtained from 41 patients ï¼»10 males, 31 females, mean age of (19.7±4.4) years (12-30 years old)ï¼½, who visited the Center for TMD and Orofacial Pain, Peking University School and Hospital of Stomatology from November 2014 to August 2019, and diagnosed with acute disc displacement without reduction or disc displacement with reduction, with intermittent locking and treated by manual disc reduction followed by anterior repositioning splint. First, condylar bone remodeling was evaluated according to the number of "double contour image" and qualitatively classified as no remodeling (no double contour image), partial remodeling (1-4 double contour images) and remarkable remodeling (5-6 double contour images). Then, condylar bone remodeling was quantitatively evaluated by CBCT based 3D measurement: segmenting condylar images using a semi-automatic method of the manually preliminary mark combined with watershed algorithm, reconstructing the surface models, superimposing the pre-and post-treatment condylar images and finally calculating the volumetric differences of condyle and condylar head, respectively. Results: The Kappa values of two-dimensional (2D) qualitative evaluation were 0.66-0.87, and 3D quantitative measurements of condyle and condylar head volume were also reliable, with the intraclass correlation coefficient (ICC) values of intra-observer 0.998/0.941 and inter-observer 0.999/0.942 respectively. The volumetric increment of the condyle and condylar head after treatment was (41.7±90.2) mm³ and (62.8±70.9) mm³, respectively. Eighty-two condyles were divided into three sub-groups: no remodeling (21), partial remodeling (20) and remarkable remodeling (41). Ranking of the volumetric increment of the condyle and condylar head after treatment was as follows: remarkable remodeling group>partial remodeling group>no remodeling group (P<0.05). Conclusions: The 3D quantitative measurement for evaluating condylar bone remodeling had excellent consistency and reliability, which was consistent with the qualitative classification for condylar bone remodeling. The condylar head as a region of interest was more sensitive to the volumetric changes.


Assuntos
Côndilo Mandibular/diagnóstico por imagem , Articulação Temporomandibular , Adolescente , Adulto , Remodelação Óssea , Criança , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Imageamento Tridimensional , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
5.
Cell Prolif ; 53(10): e12912, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32964544

RESUMO

OBJECTIVES: Mechanical force plays an important role in modulating stem cell fate and behaviours. However, how periodontal ligament stem cells (PDLSCs) perceive mechanical stimulus and transfer it into biological signals, and thereby promote alveolar bone remodelling, is unclear. MATERIALS AND METHODS: An animal model of force-induced tooth movement and a compressive force in vitro was used. After force application, tooth movement distance, mesenchymal stem cell and osteoclast number, and proinflammatory cytokine expression were detected in periodontal tissues. Then, rat primary PDLSCs with or without force loading were isolated, and their stem cell characteristics including clonogenicity, proliferation, multipotent differentiation and immunoregulatory properties were evaluated. Under compressive force in vitro, the effects of the ERK signalling pathway on PDLSC characteristics were evaluated by Western blotting. RESULTS: Mechanical force in vivo induced PDLSC proliferation, which was accompanied with inflammatory cytokine accumulation, osteoclast differentiation and TRPV4 activation; the force-stimulated PDLSCs showed greater clonogenicity and proliferation, reduced differentiation ability, improved induction of macrophage migration, osteoclast differentiation and proinflammatory factor expression. The biological changes induced by mechanical force could be partially suppressed by TRPV4 inhibition. Mechanistically, force-induced activation of TRPV4 in PDLSCs regulated osteoclast differentiation by affecting the RANKL/OPG system via ERK signalling. CONCLUSIONS: Taken together, we show here that TRPV4 activation in PDLSCs under mechanical force contributes to changing their stem cell characteristics and modulates bone remodelling during tooth movement.


Assuntos
Remodelação Óssea , Ligamento Periodontal/citologia , Células-Tronco/citologia , Canais de Cátion TRPV/metabolismo , Animais , Fenômenos Biomecânicos , Proliferação de Células , Células Cultivadas , Humanos , Masculino , Osteoclastos/citologia , Osteoclastos/metabolismo , Ligamento Periodontal/metabolismo , Ratos , Ratos Sprague-Dawley , Células-Tronco/metabolismo , Estresse Mecânico
6.
Life Sci ; 258: 118164, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32739467

RESUMO

High mobility group box-1 (HMGB1) protein is a diverse, single polypeptide moiety, present in mammalian eukaryotic cells. In response to stimuli, this nuclear protein is actively secreted in to the extracellular compartment or passively released by the necrotic cells, in order to mediate inflammatory responses, by forming complexes with IL-1α, IL-1ß, LPS and other moieties, and binding to RAGE, TLR and other receptor ligands, initiating downstream, signaling processes. This molecule acts as a proinflammatory cytokine and contributes to the progression of diseases like, acute lung injury, autoimmune liver damage, graft rejection immune response and arthritis. Small concentrations of HMGB1 are released during apoptosis, which facilitates oxidative regulation on Cys106, and propagates immune inactivating tolerogenic signals in the body. The review portrays the role of HMGB1 in rheumatoid arthritis, evidently supported by pre-clinical and clinical investigations, demonstrating extensive HMGB1 expression in synovial tissue and fluid as well as serum, excessive expression of transduction receptor signaling molecules, bone remodeling and uncontrolled expression of bone destroying osteoclastogenesis, resulting in destruction of articular cartilage, bone deformation and synovial proliferation, alleviating the pathogenesis in RA disease. Moreover, the review highlights the therapeutic regime targeting HMGB1, facilitating inhibition of its actions and release into the extracellular compartment, to ameliorate the destructive events that prevail in rheumatoid arthritis.


Assuntos
Artrite Reumatoide/patologia , Proteína HMGB1/metabolismo , Animais , Apoptose/efeitos dos fármacos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Artrite Reumatoide/fisiopatologia , Remodelação Óssea/efeitos dos fármacos , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Cartilagem Articular/fisiopatologia , Proteína HMGB1/análise , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Inflamação/fisiopatologia , Terapia de Alvo Molecular , Osteogênese/efeitos dos fármacos
7.
Artigo em Inglês | MEDLINE | ID: mdl-32630653

RESUMO

BACKGROUND: Depression and osteoporosis are severe public health problems. There are conflicting findings regarding the influence of depression on bone metabolism. The aim of the presented study was to compare bone turnover markers and vitamin D levels between patients treated for depression and healthy controls. PATIENTS AND METHODS: We determined a concentration of osteocalcin, carboxy-terminal telopeptide of type I collagen (ß-CTX), 25-hydroxyvitamin D (25OHD) and 1,25(OH)2D3 in 99 patients, aged 46.9 ± 11 years, treated for depression, as well as in 45 healthy subjects. Depressive status was determined with the Hamilton Depression Scale (HDRS). RESULTS: In patients treated for depression, we demonstrated significantly lower osteocalcin concentrations (p < 0.03) and higher concentration of ß-CTX (result on the border of significance; p = 0.08). Those relationship were stronger in women. The level of 25OHD and 1,25(OH)2D3 did not differ significantly between the examined groups. We observed a negative correlation between the 25OHD and HDRS score after treatment in all patients treated for depression and in subgroups of women and subjects with recurrent depression. CONCLUSIONS: Our results indicate that depression is related to disturbances in bone metabolism, especially in women and patients with recurrent depression, suggesting its role in context of osteoporosis development.


Assuntos
Remodelação Óssea , Osso e Ossos/metabolismo , Depressão/fisiopatologia , Adulto , Biomarcadores , Densidade Óssea , Colágeno Tipo I/metabolismo , Depressão/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina , Hormônio Paratireóideo , Vitamina D
8.
J Oral Maxillofac Surg ; 78(11): 2071.e1-2071.e11, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32649898

RESUMO

PURPOSE: The present study assessed the postoperative bone remodeling after simultaneous sagittal split ramus osteotomy (SSRO) and mandibular angle ostectomy using a 3-dimensional analysis of computed tomography (CT) data. MATERIALS AND METHODS: We designed and implemented a retrospective study that included patients who had undergone SSRO with (study group) or without (control group) mandibular angle ostectomy. Using CT data taken immediately after (T1) and 6 months (T2) after surgery, the vertical and horizontal morphologic changes of the mandibular angle were evaluated and compared between the 2 groups. In the study group, the volumetric changes of the mandibular angle were assessed, and the bone regeneration rate was calculated. RESULTS: A total of 58 mandibular angles were evaluated (32 in the study group and 26 in the control group). The study group exhibited significantly greater vertical bone regrowth at the middle and posterior regions of the mandibular angle ostectomy line compared with that in the control group (middle, P < .001; posterior, P < .001). Both groups showed significant horizontal bone regrowth at 6 months postoperatively (P < .01). In the study group, the postoperative vertical bone regrowth was significantly associated with the extent of exposed bone below the angle ostectomy line at T1 for all regions (P < .001). The percentage of postoperative regenerated bone volume relative to the volume of bone removed intraoperatively was 41.8%. CONCLUSIONS: The present findings suggest that significant bone regrowth could occur after mandibular angle ostectomy with simultaneous SSRO. Therefore, it is necessary to consider bone remodeling patterns in the treatment planning stage for better and more predictable surgical outcomes.


Assuntos
Osteotomia Sagital do Ramo Mandibular , Prognatismo , Remodelação Óssea , Cefalometria , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Prognatismo/diagnóstico por imagem , Prognatismo/cirurgia , Estudos Retrospectivos
9.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(3): 194-198, 2020 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-32621424

RESUMO

In order to evaluate the biomechanical stability of titanium alloy screw with different structural parameters under bone remodeling, some three-dimensional finite element models were established and the bone remodeling process after implanting the screw was simulated. Three-dimensional finite element models consist of bone and screw with different lengths and diameters. Bone remodeling process was simulated by user-defined subroutine. It is found that the stress on the bone is concentrated on the groove and root of the internal thread. The screw stress is mainly on the beginning of the thread, and the whole stress decreases along the long axis of the screw. The stress distribution trend of bone and screw did not change significantly during the bone remodeling. The maximum equivalent stress value was different, the maximum equivalent stress on the screw and cancellous bone increased while the maximum equivalent stress value on the cortical bone decreased.


Assuntos
Remodelação Óssea , Parafusos Ósseos , Fenômenos Biomecânicos , Análise de Elementos Finitos , Estresse Mecânico , Titânio
10.
Int J Occup Environ Med ; 11(3): 140-147, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32683426

RESUMO

BACKGROUND: The major portion of lead in the body resides in skeletal system. The bone turnover affects the release of lead into the circulation from bones. The bone turnover biomarkers (BTM) in lead-battery workers with long-term exposure to lead have not been explored yet. OBJECTIVE: To evaluate the BTM (formation and resorption) in lead-battery workers with long-term exposure to lead in lead-battery manufacturing plant. METHODS: 176 male lead-exposed workers and 80 matched comparison group were studied. All participants were examined for blood lead levels (BLLs), bone formation biomarkers- serum osteocalcin (OC), alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BALP)-and bone resorption biomarkers-serum pyridinoline (PYD), deoxypyridinoline (DPYD), tartarate-resistant acid phosphatase-5b (TRACP-5b), and urinary hydroxyproline (UHYP). RESULTS: We found a significantly higher bone formation biomarkers such as BALP (p=0.007) and bone resorption biomarkers, eg, PYD (p=0.048), TRCAP-5b (p=0.001), and UHYP (p=0.001) in lead-exposed workers. A significant (p=0.041) negative correlation (ρ ­0.128) was noted between BLLs and OC. A significant positive correlation was noted between BLLs and TRACP-5b (ρ 0.176, p=0.005) and UHYP (ρ 0.258, p=0.004). Serum OC (p=0.040) and UHYP (p=0.015) levels changed significantly with BLL level. Bone resorption biomarkers levels- PYD, TRACP-5b, and BALP-were higher among those with higher BLLs levels. The duration of exposure was significantly associated with BALP (p=0.037), DPYD (p=0.016), TRACP-5b (p=0.001), and UHYP (p=0.002) levels. CONCLUSION: Long-term lead exposure affects the bone turnover.


Assuntos
Biomarcadores/sangue , Remodelação Óssea/fisiologia , Fontes de Energia Elétrica , Chumbo/toxicidade , Exposição Ocupacional/análise , Fosfatase Ácida/sangue , Fosfatase Ácida/metabolismo , Adulto , Fosfatase Alcalina/sangue , Biomarcadores/análise , Reabsorção Óssea/sangue , Estudos de Casos e Controles , Estudos Transversais , Fontes de Energia Elétrica/efeitos adversos , Humanos , Isoenzimas/sangue , Isoenzimas/metabolismo , Chumbo/química , Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/diagnóstico , Masculino , Instalações Industriais e de Manufatura , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/estatística & dados numéricos , Osteocalcina/sangue , Local de Trabalho
11.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(7): 509-514, 2020 Jul 09.
Artigo em Chinês | MEDLINE | ID: mdl-32634892

RESUMO

Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication of anti-resorption drugs and anti-angiogenesis drugs. Its mechanism is still unclear, which may be related to bone remodeling inhibition, angiogenesis inhibition, inflammation, etc. The main clinical symptoms are continuous infection, recurrent swelling and pain and impacting the patients' quality of life. Because of its serious symptoms and unclear treatment, MRONJ has attracted wide attention. Now there are many researches on the treatment and prevention of MRONJ. The treatment includes conservative treatment and surgical treatment. There is no clear evidence of the effectiveness of existing methods of prevention and treatment of MRONJ, and lacking the unified and accepted standard methods of prevention and treatment. In this article, current researches of the prevention and treatment of MRONJ are reviewed, including the mechanism of the methods.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/terapia , Conservadores da Densidade Óssea , Osteonecrose , Remodelação Óssea , Difosfonatos , Humanos , Qualidade de Vida
12.
PLoS One ; 15(7): e0236891, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730332

RESUMO

Signal Transducer and Activator of Transcription 3 (STAT3) has recently been shown to be involved in bone development and has been implicated in bone diseases, such as Job's Syndrome. Bone growth and changes have been known for many years to differ between sexes with male bones tending to have higher bone mass than female bones and older females tending to lose bone mass at faster rates than older males. Previous studies using conditional knock mice with Stat3 specifically deleted from the osteoblasts showed both sexes exhibited decreased bone mineral density (BMD) and strength. Using the Cre-Lox system with Cathepsin K promotor driving Cre to target the deletion of the Stat3 gene in mature osteoclasts (STAT3-cKO mice), we observed that 8-week old STAT3-cKO female femurs exhibited significantly lower BMD and bone mineral content (BMC) compared to littermate control (CN) females. There were no differences in BMD and BMC observed between male knock-out and male CN femurs. However, micro-computed tomography (µCT) analysis showed that both male and female STAT3-cKO mice had significant decreases in bone volume/tissue volume (BV/TV). Bone histomorphometry analysis of the distal femur, further revealed a decrease in bone formation rate and mineralizing surface/bone surface (MS/BS) with a significant decrease in osteoclast surface in female, but not male, STAT3-cKO mice. Profiling gene expression in an osteoclastic cell line with a knockdown of STAT3 showed an upregulation of a number of genes that are directly regulated by estrogen receptors. These data collectively suggest that regulation of STAT3 differs in male and female osteoclasts and that inactivation of STAT3 in osteoclasts affects bone turnover more in females than males, demonstrating the complicated nature of STAT3 signaling pathways in osteoclastogenesis. Drugs targeting the STAT3 pathway may be used for treatment of diseases such as Job's Syndrome and osteoporosis.


Assuntos
Reabsorção Óssea/patologia , Osso e Ossos/patologia , Osteoclastos/patologia , Osteogênese , Osteoporose/patologia , Fator de Transcrição STAT3/fisiologia , Animais , Densidade Óssea , Remodelação Óssea , Reabsorção Óssea/etiologia , Osso e Ossos/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoclastos/metabolismo , Osteoporose/etiologia
13.
Comput Methods Biomech Biomed Engin ; 23(13): 959-967, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32538160

RESUMO

Remodelling and adaptation of bone within the pelvis is believed to be influenced by the mechanical strains generated during locomotion. Variation in the cortical bone thickness observed in the prenatal ilium has been linked to the musculoskeletal loading associated with in utero movements; for example the development of a thicker gluteal cortex is a possible response to contractions of the gluteal muscles. This study examines if the strains generated in the prenatal iliac cortex due to musculoskeletal loading in utero are capable of initiating bone remodelling to either maintain homeostasis or form new bone. Computational modelling techniques were used firstly to predict the muscle forces and resultant joint reaction force acting on the pelvis during a range of in utero movements. Finite element analyses were subsequently performed to calculate the von Mises strains induced in the prenatal ilium. The results demonstrated that strains generated in the iliac cortex were above the thresholds suggested to regulate bone remodelling to either maintain homeostasis or form new bone. Further simulations are required to investigate the extent to which the heterogeneous cortex forms in response to these strains (i.e., remodelling) or if developmental bone modelling plays a more pivotal role.


Assuntos
Feto/fisiologia , Análise de Elementos Finitos , Ílio/crescimento & desenvolvimento , Fenômenos Fisiológicos Musculoesqueléticos , Fenômenos Biomecânicos , Remodelação Óssea/fisiologia , Humanos , Ílio/anatomia & histologia , Ílio/diagnóstico por imagem , Modelos Biológicos , Estresse Mecânico , Microtomografia por Raio-X
14.
Nat Commun ; 11(1): 3168, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32576830

RESUMO

In humans, mutations in the PIEZO2 gene, which encodes for a mechanosensitive ion channel, were found to result in skeletal abnormalities including scoliosis and hip dysplasia. Here, we show in mice that loss of Piezo2 expression in the proprioceptive system recapitulates several human skeletal abnormalities. While loss of Piezo2 in chondrogenic or osteogenic lineages does not lead to human-like skeletal abnormalities, its loss in proprioceptive neurons leads to spine malalignment and hip dysplasia. To validate the non-autonomous role of proprioception in hip joint morphogenesis, we studied this process in mice mutant for proprioceptive system regulators Runx3 or Egr3. Loss of Runx3 in the peripheral nervous system, but not in skeletal lineages, leads to similar joint abnormalities, as does Egr3 loss of function. These findings expand the range of known regulatory roles of the proprioception system on the skeleton and provide a central component of the underlying molecular mechanism, namely Piezo2.


Assuntos
Canais Iônicos/metabolismo , Anormalidades Musculoesqueléticas/metabolismo , Sistema Musculoesquelético/metabolismo , Neurônios/metabolismo , Propriocepção/fisiologia , Anormalidades Múltiplas , Animais , Remodelação Óssea , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Modelos Animais de Doenças , Proteína 3 de Resposta de Crescimento Precoce/metabolismo , Predisposição Genética para Doença/genética , Luxação do Quadril/genética , Luxação do Quadril/metabolismo , Luxação do Quadril/patologia , Articulação do Quadril/anatomia & histologia , Articulação do Quadril/metabolismo , Articulação do Quadril/patologia , Canais Iônicos/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Anormalidades Musculoesqueléticas/genética , Anormalidades Musculoesqueléticas/patologia , Sistema Musculoesquelético/patologia , Escoliose
15.
J Contemp Dent Pract ; 21(4): 463-470, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32584287

RESUMO

AIM: The purpose of this study was to evaluate the degree of vertical peri-implant resorption around implants inserted with an inclination increased more than 10° at a distance of at least 1 year from insertion. MATERIALS AND METHODS: For the realization of the study, a sample consisting of 47 patients for a total of 115 implants was selected. We excluded all those subjects whose conditions could have compromised the outcome of the treatment. An orthopantomography of the dental arches was made using Orthophos XG 3D Sirona at time T0 (at the end of definitive insertion of prosthesis) and at time T1 (at least 1 year after T0) with the aim of an individualized positioner. In this study, all the implants with inclination equal to or greater than 10° were subdivided into three groups, and the implants with inclination between 0 and 10 were used as control sample. RESULTS: In group I, there is a statistically significant difference in at least one of the two sides (distal one) between T0 and T1. In groups II and III, there is a statistically significant difference in the degree of bone resorption on the mesial side with respect to distal side. In group IV, a statistically significant difference on both sides was evidenced. The implant survival at a distance of 1 year was equal to 100% of cases. CONCLUSION: Surgeons must take into account the possibility that an increase in inclination of implants may lead to a more rapid resorption of bone mesially or distally. CLINICAL SIGNIFICANCE: The direction of the prosthetic load transmitted to the fixture is a variable that could influence the degree of reabsorption of both mesial and distal bone structures according to both laboratory and clinical data.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Remodelação Óssea , Prótese Ancorada no Osso , Implantação Dentária Endo-Óssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Seguimentos , Humanos
16.
Sports Health ; 12(4): 334-340, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525466

RESUMO

BACKGROUND: Female runners are at increased risk of stress fractures (SFs) compared with men. Literature is lacking with regard to best practice for preventing and treating SFs in women. The purpose of the study was to compare physiological measures and running-related factors between women of various ages and running abilities with and without a history of running-related SFs. HYPOTHESIS: Women with and without SF histories will differ with regard to medical and menstrual history, bone health, body composition, nutrition, and running history. STUDY DESIGN: Prospective cohort study. LEVEL OF EVIDENCE: Level 2. METHODS: A total of 20 female runners with SF histories were matched based on age and running distance with 20 women without SF histories. Data included medical, menstrual, running, injury, and nutritional histories; blood histology related to nutritional, hormonal, and bone-related risk factors; and bone density, fat, and lean tissue using dual energy x-ray absorptiometry. Paired t tests were used to examine differences between women with and without SF histories, and Spearmen correlations were conducted to examine relationships between physiological factors. RESULTS: Women with SF histories had lower hip bone mineral density compared with women without SF histories (P < 0.05). SF history was moderately correlated with menstrual changes during increased training times (r = 0.580; P < 0.0001) but was not correlated with any other physiological factor. There was a moderate correlation within the SF group (r = 0.65; P = 0.004) for bone markers for resorption and formation both increasing, indicating increased bone turnover. CONCLUSION: Female runners with low hip bone mineral density, menstrual changes during peak training, and elevated bone turnover markers may be at increased risk of SF. CLINICAL RELEVANCE: Female runners need routine screening for risks associated with SF occurrence. As bone mineral density and bone turnover markers are not routinely assessed in this population, important risk factors may be missed.


Assuntos
Fraturas de Estresse/fisiopatologia , Corrida/fisiologia , Adulto , Biomarcadores/sangue , Distribuição da Gordura Corporal , Índice de Massa Corporal , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Feminino , Humanos , Menstruação , Pessoa de Meia-Idade , Condicionamento Físico Humano/fisiologia , Projetos Piloto , Estudos Prospectivos , Fatores de Risco , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem
17.
Environ Sci Pollut Res Int ; 27(27): 33998-34004, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32557063

RESUMO

In conditions of intensive development of gas fields, environmental safety issues are becoming increasingly important. High rates of gas production and growth of its chemical processing have turned gas industry enterprises into a powerful source of environmental pollution, which poses a real threat to public health and contributes to an increase in morbidities and environmentally determined pathological conditions. The development of methods for the diagnosis, treatment and prevention of such conditions is an important task for modern science. The aim of the research is to make a comprehensive assessment of serum markers of bone synthesis and resorption in children with short stature living in the oil and gas processing regions. A total of 240 children aged 8-17 years, living in the oil and gas processing region (Kenkiyak), and 409 schoolchildren (8-17 years old), living in the environmentally favourable region (Kobda village), during 3 years were examined. It was established that emissions of pollutants by oil processing enterprises account for almost 80% of all emissions into the atmosphere. Gas flaring at oil production sites plays a special role in this process. Speaking of the effects of environmental factors on children's health, it should be noted that there is no consensus on the mechanisms and consequences of exposure to low doses of chemical atmospheric pollutants in children and adolescents so far.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Ambientais , Adolescente , Atmosfera , Remodelação Óssea , Criança , Poluição Ambiental , Humanos , Campos de Petróleo e Gás
18.
J Vis Exp ; (159)2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32510503

RESUMO

Bone remodeling is a tightly regulated process that is required for skeletal growth and repair as well as adapting to changes in the mechanical environment. During this process, mechanosensitive osteocytes regulate the opposing responses between the catabolic osteoclasts and anabolic osteoblasts. To better understand the highly intricate signaling pathways that regulate this process, our lab has developed a foundationary lab-on-a-chip (LOC) platform for analyzing functional outcomes (formation and resorption) of bone remodeling within a small scale system. As bone remodeling is a lengthy process that occurs on the order of weeks to months, we developed long-term cell culturing protocols within the system. Osteoblasts and osteoclasts were grown on functional activity substrates within the LOC and maintained for up to seven weeks. Afterward, chips were disassembled to allow for the quantification of bone formation and resorption. Additionally, we have designed a 3D printed mechanical loading device that pairs with the LOC platform and can be used to induce osteocyte mechanotransduction by deforming the cellular matrix. We have optimized cell culturing protocols for osteocytes, osteoblasts, and osteoclasts within the LOC platform and have addressed concerns of sterility and cytotoxicity. Here, we present the protocols for fabricating and sterilizing the LOC, seeding cells on functional substrates, inducing mechanical load, and disassembling the LOC to quantify endpoint results. We believe that these techniques lay the groundwork for developing a true organ-on-a-chip for bone remodeling.


Assuntos
Remodelação Óssea , Dispositivos Lab-On-A-Chip , Mecanotransdução Celular , Osteócitos/citologia , Animais , Humanos , Osteoblastos/citologia , Osteoclastos/citologia , Osteogênese
19.
J Sports Sci ; 38(18): 2080-2091, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32530734

RESUMO

Acute and adaptive changes in systemic markers of oxidatively generated nucleic acid modifications (i.e., 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo)) as well as inflammatory cytokines (i.e., C-reactive protein, interleukin-6, interleukin-10, and tumour necrosis factor alpha), a liver hormone (i.e., fibroblast growth factor 21 (FGF21)), and bone metabolism markers (sclerostin, osteocalcin, C-terminal telopeptide, and N-terminal propeptide of type 1 procollagen) were investigated following a marathon in 20 study participants. Immediate changes were observed in inflammatory cytokines, FGF21, and bone metabolism markers following the marathon. In contrast, no immediate changes in urinary excretion of 8-oxodG and 8-oxoGuo were evident. Four days after the marathon, decreased urinary excretion of 8-oxodG (-2.9 (95% CI -4.8;-1.1) nmol/24 h, P < 0.01) and 8-oxoGuo (-5.8 (95% CI -10.3;-1.3) nmol/24 h, P = 0.02) was observed. The excretion rate of 8-oxodG remained decreased 7 days after the marathon compared to baseline (-2.3 (95%CI -4.3;-0.4) nmol/24 h, P = 0.02), whereas the excretion rate of 8-oxoGuo was normalized. In conclusion marathon participation immediately induced a considerable inflammatory response, but did not increase excretion rates of oxidatively generated nucleic acid modifications. In fact, a delayed decrease in oxidatively generated nucleic acid modifications was observed suggesting adaptive antioxidative effects following exercise. ABBREVIATIONS: 8-oxodG: 8-oxo-7,8-dihydro-2'-deoxyguanosine; 8-oxoGuo: 8-oxo-7,8-dihydroguanosine; CI: confidence interval; CTX: C-terminal telopeptide of type 1 collagen; DXA: dual-energy X-ray absorptiometry; ELISA: enzyme-linked immunosorbent assay; FGF21: Fibroblast growth factor 21; h: hour; hsCRP: high sensitivity C-reactive protein; IL: interleukin; IQR: interquartile range; MS: mass spectrometry: P1NP: N-terminal propeptide of type 1 procollagen; TNFα: tumour necrosis factor alpha; UPLC: ultra-performance liquid chromatography.


Assuntos
Inflamação/sangue , Inflamação/urina , Estresse Oxidativo , Resistência Física/fisiologia , Corrida/fisiologia , 8-Hidroxi-2'-Desoxiguanosina/urina , Biomarcadores/sangue , Biomarcadores/urina , Remodelação Óssea , Creatinina/urina , Citocinas/sangue , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
20.
Ann Agric Environ Med ; 27(2): 219-224, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32588596

RESUMO

INTRODUCTION: Osteoporosis, the "quiet epidemic", is one of the most serious threats to public health. It is known that estrogen plays a significant role in the regulation of bone turnover, and its loss at menopause causes osteoporosis. Added to this, insufficient calcium intake accelerates bone mass loss, increasing the risk of fractures. OBJECTIVE: The study aimed to answer the question whether a fructan-enriched diet could be helpful in preventing from disturbances in bone turnover caused by calcium restriction combined with ovariectomy-induced estrogen deficiency. The differences related to the kind of fructan and 'matrix effect' of fructan action (form of addition) were also evaluated. MATERIAL AND METHODS: The study was conducted using sham-operated (control groups) or ovariectomized (OVX) rats fed a calcium restricted diet. The treatment diets contained one of three fructan sources - Jerusalem artichoke, yacon and Beneo Orafti Synergy1 - added alone or as an ingredient of strawberry sorbet, all in the amount providing 8% fructans. Analyses of biological material included: serum Ca, Mg and P concentrations, alkaline phosphatase activity (ALP), osteocalcin (OC) and C-telopeptide degradation products from type I collagen (CTX). Densitometric parameters of femora were also assayed. RESULTS: Among markers of bone turnover, the ALP activity depended both on the kind of fructan and the form of addition. The highest value was shown in the OVX group fed a low-calcium diet, whereas administration of diet enriched with Jerusalem artichoke led to an almost 50% decrease in the value of this parameter. Dietary fructans also lowered the OC level. Feeding rats with diet containing sorbet enriched in yacon or Jerusalem artichoke resulted in a decrease of CTX, compared to the diet containing yacon alone or fructan formulation in both forms No significant differences were observed in densitometric parameters between treatment groups. CONCLUSIONS: The obtained findings suggest that fructan administration with a calcium-restricted diet might exert a positive effect on bone turnover parameters. Regarding the form of their addition, it is possible that other constituents of sorbets contributed to the fructan action. It remains open whether this impact would be significant over a longer period of time.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Cálcio/deficiência , Fêmur/efeitos dos fármacos , Frutanos/metabolismo , Osteoporose/prevenção & controle , Ovariectomia , Ração Animal/análise , Animais , Cálcio/administração & dosagem , Cálcio na Dieta/administração & dosagem , Dieta , Suplementos Nutricionais/análise , Feminino , Frutanos/administração & dosagem , Ratos , Ratos Wistar
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