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1.
Mol Cell Endocrinol ; 581: 112113, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37989409

RESUMO

Although disorders of primary cilia (PCs) were first reported in human papillary thyroid cancer (PTC) tissues in 1987, their precise role in PTC remains unclear. PCs sense the thyroid follicle colloid environment and act as a cell signaling hub. The present study investigated whether PCs are needed for BRAFV600E-driven PTC. We assessed whether BRAFV600E protein expression correlates with papillary histological architecture and clinicopathological features of PTC. We found that expression of ciliary intraflagellar transport 88 (IFT88) and PC formation were reduced in BRAFV600E-driven PTCs and that loss of cilia may be associated with lymph node metastasis. In PTC cells, the BRAFV600E mutation maintained the aggressiveness of PTC, which was partially related to loss of PCs. Our work confirms that BRAFV600E mutation-driven PC downregulation contributes to maintaining the aggressiveness of PTCs and that manipulating PC can potentially reduce the adverse incidence of PTC in a range of conditions.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Cílios/metabolismo , Regulação para Baixo/genética , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Mutação/genética
2.
Cardiovasc Diabetol ; 21(1): 74, 2022 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-35568946

RESUMO

Cardiovascular diseases (CVDs) are the main cause of death among patients with type 2 diabetes mellitus (T2DM), particularly in low- and middle-income countries. To effectively prevent the development of CVDs in T2DM, considerable effort has been made to explore novel preventive approaches, individualized glycemic control and cardiovascular risk management (strict blood pressure and lipid control), together with recently developed glucose-lowering agents and lipid-lowering drugs. This review mainly addresses the important issues affecting the choice of antidiabetic agents and lipid, blood pressure and antiplatelet treatments considering the cardiovascular status of the patient. Finally, we also discuss the changes in therapy principles underlying CVDs in T2DM.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Glicemia , Pressão Sanguínea , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemiantes/efeitos adversos , Lipídeos
3.
Cancer Med ; 11(4): 1136-1144, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35032114

RESUMO

BACKGROUND: The prevalence of obesity and an increased incidence of thyroid carcinoma (TC) threaten public health in parallel on a global scale. Sufficient evidence supports excess body fatness in thyroid carcinogenesis, and the role and anthropometric markers of obesity have been causally associated with the rising risk of TC. METHODS: A literature search was conducted in PubMed. Studies focused on the effect of obesity in TC. RESULTS: This review mainly discusses the global incidence and prevalence of obesity-related TC. We also review the role of obesity in TC and potential clinical strategies for obesity-related TC. CONCLUSIONS: Excess body fatness in early life and TC survival initiate adverse effects later in life.


Assuntos
Obesidade , Neoplasias da Glândula Tireoide , Humanos , Incidência , Obesidade/complicações , Obesidade/epidemiologia , Prevalência , Fatores de Risco , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia
4.
Front Endocrinol (Lausanne) ; 12: 685228, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34168619

RESUMO

Primary cilia (PC) are microtubule-based organelles that are present on nearly all thyroid follicle cells and play an important role in physiological development and in maintaining the dynamic homeostasis of thyroid follicles. PC are generally lost in many thyroid cancers (TCs), and this loss has been linked to the malignant transformation of thyrocytes, which is regulated by PC-mediated signaling reciprocity between the stroma and cancer cells. Restoring PC on TC cells is a possible promising therapeutic strategy, and the therapeutic response and prognosis of TC are associated with the presence or absence of PC. This review mainly discusses the role of PC in the normal thyroid and TC as well as their potential clinical utility.


Assuntos
Cílios , Neoplasias da Glândula Tireoide , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Cílios/efeitos dos fármacos , Cílios/metabolismo , Cílios/patologia , Proteínas Hedgehog/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia
5.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(1): 30-36, 2020 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-32037763

RESUMO

OBJECTIVE: This study aims to investigate the occlusal and myoelectric characteristics of implant-supported fixed denture in the mandibular region and provide reference for the design of fixed restoration. METHODS: Sixty edentulous patients with implant-supported fixed denture were selected and divided into three groups: group A, 20 cases with implant-supported fixed restoration in the maxillary region; group B, 20 cases with natural dentition, and group C, 20 cases with removable partial denture. The T-scan 8.0 digital occlusion analysis system was used to evaluate the occlusal characteristics of patients in the three groups at intercuspal, protrusion, and left and right lateral positions. Electromyography was used to analyze the myoelectric amplitude and bilateral asymmetry index of the anterior temporalis and masseter of the three groups in different states such as resting and clenching. The relationship between occlusion and myoelectricity was also investigated. RESULTS: In the occlusion analysis by T-scan, the occlusion time, the balance of left and right bite force, the left and right asymmetry of the occlusion center, the trajectory of central occlusion force, and the disclusion time were higher in group C than in groups A and B (P<0.05). No significant differences were observed in the anterior and posterior asymmetry of the occlusion center and percentage of bite force at anterior region among the three groups. In the analysis of myoelectricity, the myoelectric amplitude at resting state and the asymmetry index of masticatory muscles in group C were higher than those in groups A and B (P<0.05). The myoelectric amplitude during clenching in groups A and B groups was higher than that in group C (P<0.05). CONCLUSIONS: In implant-supported fixed restoration at edentulous mandibular, when maxillary includes the removable partial denture, degree of occlusal instability and left and right asymmetry of occlusion center are greater than those with the natural dentition and implant-supported fixed denture at maxillary. The myoelectricity is closely related to occlusion. The removable partial denture can increase the myoelectric activity and reduce the potential of the masticatory muscle. The asymmetry of bilateral myoelectricity is related to the occlusion imbalance.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante , Força de Mordida , Humanos , Mandíbula , Músculos da Mastigação
6.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 36(6): 628-632, 2018 12 01.
Artigo em Chinês | MEDLINE | ID: mdl-30593108

RESUMO

OBJECTIVE: This study aims to evaluate the occlusal characteristics of full edentulous patients with implant-supported prostheses and to provide a reference with the occlusal situation for clinicians. METHODS: A Teetester occlusal analysis system was used with 30 full edentulous patients of implant-supported fixed denture (test group) in comparison with 30 natural dentition (control group). The percentage of occlusal force distribution were measured, as well as the occlusal time at the intercuspal, protrusion, and left and right lateral positions. RESULTS: Compared with control group, the occlusion time, maximum occlusal force in intercuspal of test group significantly reduced (P<0.05); while control group was obviously superior to test group in the left and right bit force degree. Disclusion time in protrusion, occlusion times in lateral positions of test group also significantly reduced (P<0.05). There were no significant differences in average occlusion force, percentage of total force in anterior teeth, and lateral occlusion between test group and control group. CONCLUSIONS: The maximum occlusal force in intercuspal of full edentulous patients with implant-supported prostheses reduce. The occlusal force in protrusive occlusion is concentrated in the front teeth, and the group function occlusion is the main lateral occlusal pattern.


Assuntos
Oclusão Dentária , Má Oclusão , Boca Edêntula , Força de Mordida , Prótese Dentária Fixada por Implante , Dentaduras , Humanos
7.
J BUON ; 21(2): 461-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27273959

RESUMO

PURPOSE: Recent studies in several tumors showed that presence of cancer stem like side population (SP) cells are responsible for chemotherapeutic drugs resistance and tumor relapse. In our present study, we have analyzed the role of SP cells in oral squamous cell carcinoma cell (OSCC) line OSCC-77. METHODS: The oral cancer cell line OSCC-77 was analyzed for the presence of SP cells by FACS using Hoechst 33342 dye exclusion method. Further the FACS-sorted SP and non-SP cells were subjected to drug resistance and sphere formation assays. RESULTS: We identified that the presence of SP cells in OSCC-77 cell line was 3.4%, which was reduced to 0.6% in the presence of verapamil, an inhibitor of ABC transporter. Furthermore, we showed that these SP cells were highly drug-resistant, had increased survival and were highly potent for self-renewal. Also, the clone formation efficiency of SP cells was significantly higher compared to non-SP cells (p<0.01). CONCLUSION: Our data suggest that cancer stem-like SP cells of OSCC-77 cell line contribute to multidrug resistance and are highly involved in tumor relapse. However, further characterization of SP cells at gene expression level and their signaling pathways might provide new insights into the development of novel anticancer drugs.


Assuntos
Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias Bucais/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Células da Side Population/efeitos dos fármacos , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Autorrenovação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células da Side Population/metabolismo , Células da Side Population/patologia , Verapamil/farmacologia
8.
Electromagn Biol Med ; 35(1): 75-83, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25333898

RESUMO

Effects of sinusoidal electromagnetic fields (SEMFs) on bone metabolism have not yet been well defined. The present study investigated SEMF effects on bone formation and resorption in rat femur bone tissues in vitro. Cultured femur diaphyseal (cortical bone) and metaphyseal (trabecular bone) tissues were treated with 50 Hz 1.8 mT SEMFs 1.5 h per day for up to 12 days and treatment effects on bone formation and resorption markers and associated gene expression were examined. Treatment with SEMFs caused a significant increase in alkaline phosphatase (ALP) activity and inhibited the tartrate-resistant acid phosphatase (TRACP) activity in the femoral diaphyseal or metaphyseal tissues. SEMFs also significantly increased levels of mRNA expression of osterix (OSX), insulin-like growth factor (IGF-1) and ALP in the bone tissues. SEMF treatment decreased glucose content and increased lactic acid contents in the culture conditioned medium. In addition, treatment with SEMFs decreased mRNA expression levels of bone resorption-related genes TRACP, macrophage colony stimulating factor (M-CSF) and cathepsin K (CTSK) in the cultured bone tissues. In conclusion, the current study demonstrated that treatment with 1.8 mT SEMFs at 1.5 h per day promoted bone formation, increased metabolism and inhibited resorption in both metaphyseal and diaphyseal bone tissues in vitro.


Assuntos
Reabsorção Óssea/terapia , Campos Eletromagnéticos , Fêmur/efeitos da radiação , Magnetoterapia , Osteogênese/efeitos da radiação , Fosfatase Ácida/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Reabsorção Óssea/fisiopatologia , Fêmur/metabolismo , Fêmur/fisiologia , Fêmur/fisiopatologia , Regulação da Expressão Gênica/efeitos da radiação , Glucose/metabolismo , Isoenzimas/metabolismo , Ácido Láctico/metabolismo , Masculino , Osteogênese/genética , Ratos , Ratos Wistar , Fosfatase Ácida Resistente a Tartarato
9.
Zhongguo Gu Shang ; 28(9): 832-7, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26647566

RESUMO

OBJECTIVE: To investigate osthole effect on femoral tissue resorption activity of rat in vitro. METHODS: Six SD rats weighted (80 ± 5) g were used to isolate and culture femoral tissue (diaphyses and metaphysis) in vitro. The cultured tissue were devided into control group, estradiol group and osthole group. The femoral tissue was treated with final concentration of 1 x 10(-5) mol/L osthole and 1 x 10(-8) mol/L estradiol culture in vitro at 48 hours after cultured. Tartrate-resistant acid phosphatase (StrACP) activity, glucose and Lactic acid content, StrACP, MCSF (Macrophage colony stimulating factor) and CTSK (Cathepsin K) mRNA was detected by Real-Time RT-PCR were detected. RESULTS: Concetration of Alkaline phosphatase activity were 2226 and 2498 in 1 x 10(-5) mol/L osthole and 1 x 10(-8) mol/L estradiol respectively. As compared with control group, the activity of StrACP of 1 x 10(-5) mol/L osthole and 1 x 10(-8) mol/L estradiol were inhibited at 6, 9, 12 days (P < 0.05); under treatment of in l x 10(-5) mol/L osthole, the content of Lactic acid were increased and the content of glucose were decreased at 3, 6, 9 days (P < 0.05); StrACP, MCSF and CTSK mRNA expression level were inhibited at 6, 9 days (P < 0.05). CONCLUSION: Osthole can inhibit bone resorption and raise the level of nutrition metabolism of femurs tissue.


Assuntos
Reabsorção Óssea/prevenção & controle , Cumarínicos/farmacologia , Fêmur/efeitos dos fármacos , Fosfatase Ácida/metabolismo , Animais , Estradiol/farmacologia , Glucose/análise , Ácido Láctico/análise , Masculino , Ratos , Ratos Sprague-Dawley
10.
Zhongguo Gu Shang ; 28(6): 547-52, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26255483

RESUMO

OBJECTIVE: To establish osteoblast model, primary cilla model was removed by chloral hyrate, observe effects of osteoblast primary cilla moved on enhancing ALP staining and calcified nodules staining in electromagnetic field. METHODS: Three 3-day-old male SD rats weighed between 6 and 9 g were killed, cranial osteoblast was drawed and adherencing cultured respectively. Cells were subcultured and randomly divided into 4 groups until reach to fusion states. The four groups included chloral hydrate non-involved group (control group), 2 mM, 4 mM and 8 mM chloral hydrate group, and cultured in 37 °C, 5% CO2 incubator for 72 h. Morphology of primary cilla was observed by laser confocal scanning microscope, and incidence of osteoblast primary cilia was analyzed by Image-Pro Plus 6.0 software. Cells in the correct concentration group which can removed cillia most effectively were selected and divided into 3 groups, including control group (C), Electromagnetic fields group (EMFs), and EMFs with 4 mM chloral hydrate group. DMEM nutrient solution contained 10%FBS were added into three groups and cultured for 9 days and formation of ALP were observed by histochemical staining of alkaline phosphatase. After 12 days' cultivation, formation of mineralization nodes was observed by alizarin red staining. RESULTS: Compared with control group and 2mM chloral hydrate group,4 mM chloral hydrate group could effectively remove osteoblast primary cilla (P<0.01). Removal of osteoblast primary cilla could weaken the formation of ALP and mineralization nodes in osteoblast in EMFS. Compared with EMFs group, the area of ALP and mineralization nodes in EMFs with 4 mM chloral hydrate group were decreased obviously (P<0.01). CONCLUSION: 4mM chloral hydrate could effectively remove osteoblast primary cilia. Primary cilla participate in EMFs promoting formation of ALP and mineralization nodes in osteoblast and provide new ideas for exploring mechanism of EMFs promoting osteoblast maturation and mineralization.


Assuntos
Técnicas de Cultura de Células/métodos , Hidrato de Cloral/farmacologia , Cílios/fisiologia , Osteoblastos/citologia , Fosfatase Alcalina/metabolismo , Animais , Técnicas de Cultura de Células/instrumentação , Células Cultivadas , Cílios/efeitos dos fármacos , Cílios/enzimologia , Masculino , Osteoblastos/enzimologia , Ratos , Ratos Sprague-Dawley
11.
Mol Cell Endocrinol ; 404: 132-40, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25661534

RESUMO

Although pulsed electromagnetic fields (PEMFs) have been approved as a therapy for osteoporosis, action mechanisms and optimal parameters are elusive. To determine the optimal intensity, exposure effects of 50 Hz PEMFs of 0.6-3.6 mT (0.6 interval at 90 min/day) were investigated on proliferation and osteogenic differentiation of cultured calvarial osteoblasts. All intensity groups stimulated proliferation significantly with the highest effect at 0.6 mT. The 0.6 mT group also obtained the optimal osteogenic effect as demonstrated by the highest ALP activity, ALP(+) CFU-f colony formation, nodule mineralization, and expression of COL-1 and BMP-2. To verify our hypothesis that the primary cilia are the cellular sensors for PEMFs, osteoblasts were also transfected with IFT88 siRNA or scrambled control, and osteogenesis-promoting effects of 0.6 mT PEMFs were found abrogated when primary cilia were inhibited by IFT88 siRNA. Thus primary cilia of osteoblasts play an indispensable role in mediating PEMF osteogenic effect in vitro.


Assuntos
Calcificação Fisiológica , Magnetoterapia/instrumentação , Magnetoterapia/métodos , Osteoblastos/fisiologia , Osteogênese , Crânio/citologia , Fosfatase Alcalina , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Cílios , Campos Eletromagnéticos , Técnicas In Vitro , Osteoblastos/citologia , Ratos , Proteínas Supressoras de Tumor/genética
12.
Zhongguo Gu Shang ; 27(7): 587-91, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25338447

RESUMO

OBJECTIVE: To compare the ability of osthole (OST) and genistein (GEN) in enhancing bone peak bone mass of rats to prevent osteoporosis. METHODS: Thirty-six female one-month-old SD rats of (125 +/- 3) g body weight were randomly divided into three groups, 12 rats in each group, one group was orally administered osthole at 9 mg x kg(-1) d(-1), one group was given genistein at 10 mg x kg(-1) d(-1) and another was given equal quantity of distilled water as the control. The body weight was monitored weekly and the bone mineral density (BMD) of total body was measured every month. All rats were sacrificed after three months, the femoral bone mineral density, the serum levels of osteocalcin (OC) and anti-tartaric acid phosphatase 5b (TRACP 5b) were measured by Elisa. The bone microarchitectures were analyzed with micro-CT and the bone biomechanics properties were tested with universal material machine. RESULTS: No significant differences were observed between O-treated or GEN group and the control for the food-intake and body weight during three months. However, the rats treated with OST had significant higher BMD for both total body and femur than the control and GEN group. The O-treated rats also had higher level of serum OC and lower level of TRACP 5b. Besides, they owned bigger bone volume/tissue volume, trabecular thickness, trabecular number but smaller trabecular spacing. In the three point bending tests of femurs,they were found to have larger maximum load, the young's modulus and structural model index (SMI). CONCLUSION: Orally administered osthole could efficiently increase the peak bone mass of rats,which provide new ideas for preventing osteoporosis.


Assuntos
Densidade Óssea/efeitos dos fármacos , Cumarínicos/farmacologia , Genisteína/farmacologia , Fosfatase Ácida/sangue , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Fêmur/patologia , Isoenzimas/sangue , Osteocalcina/sangue , Radiografia , Ratos , Ratos Sprague-Dawley , Fosfatase Ácida Resistente a Tartarato
13.
Zhongguo Zhong Yao Za Zhi ; 39(14): 2704-9, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25272500

RESUMO

OBJECTIVE: To investigate the estrogenic activity of icariin and genistein with estrogen-dependent human breast cancer (MCF-7) cells. METHOD: MCF-7 cells were incubated with media containing 5% charcoal dextran-treated FBS in phenol red-free media for 48 h. CCK-8 kit was used to study the impact of defferent concentration of icariin and genistein on MCF-7 proliferation in vitro. Optimal concentration icariin and genistein were added into medium and total RNA was isolated after 12, 24, 36, 48 h. The gene expression of ERalpha, ERbeta, PS2, and PR were investigated by Real-time RT-PCR Total protein was also isolated and secretion of ERalpha, ERbeta, PS2, and PR were examined by Western blot. RESULT: 10 micromol x L(-1) icariin and genistein could promote the proliferation of MCF-7 evidently. However, the ability of genistein to promote the proliferation was better than icariin. With the concentration of 10 micromol x L(-1), genistein group had a stronger expression of ERa, PS2 and PR mRNA levels than icariin while ERbetaexpression had no significant difference in two group. The same effects were detected by western blotting. CONCLUSION: Both genistein and icariin have a strong estrogen-like effect, but the estrogenic activity of genistein is stronger than icariin. It showed that the activity of icariin is stron-ger than genistein to promote ROB maturation. So it must be that icariin promotes the maturation of osteoblasts in vitro by a estogen-independent mechanism.


Assuntos
Flavonoides/farmacologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Estrogênios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genisteína/farmacologia , Humanos , Células MCF-7 , Osteoblastos/metabolismo , Presenilina-2/metabolismo
14.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 43(3): 359-65, 2014 05.
Artigo em Chinês | MEDLINE | ID: mdl-24998662

RESUMO

The primary cilium is a solitary and special organelle that emanates from the cell surface of most mammalian cells, which is anchored to the cell by mother centriole during the interphase and G0 of cell cycle. Recent studies have revealed that the primary cilium is a sensory organelle to receive extracellular signals and plays a key role in the signal transduction and pathogenesis of diseases. This review presents the structure and the forming process of the primary cilium during cell cycle. The signal transductions associated with primary cilium, including platelet-derived growth factor receptor αα, hedgehog, Wnt are discussed and the relevant researches in the future are proposed.


Assuntos
Cílios/fisiologia , Transdução de Sinais/fisiologia , Humanos
15.
Mater Sci Eng C Mater Biol Appl ; 42: 657-64, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25063166

RESUMO

Plasma electrolytic oxidation (PEO) is one of the most applicable methods to produce bioceramic coating on a dental implant and sandblasting is a primary technique to modify metal surface properties. This study aims to deposit bioceramic Ca- and P-containing coatings on sandblasted commercially pure titanium by PEO technique to improve its bioactive performance. The time-dependent modified surfaces are characterized in terms of their microstructure, phase, chemical composition, mechanical properties and bioactivities. The results show that the combination-treated coating exhibits better properties than the PEO-treated one, especially in bioactivities, as evidenced by the HA formation after immersion in simulated body fluid (SBF) for 5 days and the cell viability after seeding for 1 or 3 days. The enhancement of the modified surface is attributed to a combination of the mechanical sandblasting and the microplasma oxidation.


Assuntos
Materiais Revestidos Biocompatíveis/química , Técnicas Eletroquímicas/métodos , Oxirredução , Titânio/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Camundongos
16.
Bone ; 66: 189-98, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24956021

RESUMO

Icariin, a prenylated flavonol glycoside isolated from Epimedii herba, has been found to be a potent stimulator of osteogenic differentiation and has potential application in preventing bone loss. However, the signaling pathway underlying its osteogenic effect remains unclear. We hypothesized that the osteogenic activity of icariin is related to the nitric oxide (NO) signal pathway and PI3K/AKT pathway in its upstream. Rat bone marrow stromal cells (rBMSCs) were cultured in osteogenic medium and treated with icariin or together with L-NAME, ODQ, PDE5, and/or LY294002 (the inhibitor of NOS, sGC, cGMP, and PI3K respectively), and effects were examined on the expression of signal messengers (NOS, NO, sGC, cGMP, PKG and PI3K) and the levels of osteogenic markers (alkaline phosphatase or ALP, osteocalcin and calcified nodules). It was found that icariin dose-dependently increased ALP activity, and treatment at the optimal concentration (10(-5)M) increased NOS activity, iNOS and eNOS expression, NO production, sGC and cGMP contents and PKG expression besides the phosphorylation of AKT. The addition of L-NAME, ODQ and PDE5 significantly inhibited the icariin effects on above markers respectively. The addition of LY294002 decreased the p-AKT level, NOS activity, eNOS expression and NO production significantly, but had no significant effect on iNOS expression. The addition of any of the four inhibitors also abolished the osteogenic effect of icariin on rBMSCs as indicated by ALP activity, osteocalcin synthesis, calcium deposition and the number and areas of calcified nodules. These results suggest that the osteogenic effect of icariin involves the PI3K-AKT-eNOS-NO-cGMP-PKG signal pathway. Furthermore, dosage response studies showed that icariin at 10(-6)M (a physiologically achievable concentration in vivo) also activated this signal pathway.


Assuntos
Diferenciação Celular/efeitos dos fármacos , GMP Cíclico/metabolismo , Flavonoides/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/enzimologia , Óxido Nítrico/metabolismo , Osteogênese/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Cromonas/farmacologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Morfolinas/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Osteocalcina/metabolismo , Fenótipo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
17.
Zhongguo Gu Shang ; 27(11): 933-7, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25577917

RESUMO

OBJECTIVE: To investigate the effects of different-intensity sinusoidal electromagnetic fields (SEMFs) on bone mineral density (BMD) and histomorphometry in SD rats. METHODS: Thirty female SD rats were randomly divided into three groups: group A (a control group), group B (0.1 mT group) and group C (0.6 mT group). The rats in group B and C were exposed to 50 Hz SEMFs 3 hours each day. However,the magnetic intensity was different between group B and group C:0.1 mT for group B and 0.6 mT for group C. After 8 weeks, all the animals were killed. Changes of BMD and histomorphometric properties were observed. RESULTS: Compared with group A, the BMD of whole body, femur and vertebrae of rats in group B increased significantly; the area percentage, number and width of bone trabeculae in vertebrae and femur of rats in group B were larger than those of group A; but the resolution of bone trabeculae of rats in group B was lower than that of group A. The trabecular number in group C rats were significantly decreased, compared with that in group A rats. The outcome of double fluorescence labeling in group B was found to be significantly different with that in group A. But the difference between rats in group A and C was not significant. CONCLUSION: This study demonstrates that 50 Hz 0.1 mT SEMFs can increase BMD, improve bone tissue microstructure and, promote bone formation.


Assuntos
Densidade Óssea/efeitos da radiação , Campos Eletromagnéticos , Vértebras Lombares/efeitos da radiação , Tíbia/efeitos da radiação , Animais , Feminino , Vértebras Lombares/patologia , Osteogênese/efeitos da radiação , Ratos , Ratos Sprague-Dawley , Tíbia/patologia
18.
Bioelectromagnetics ; 35(1): 30-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23775573

RESUMO

Noninvasive electromagnetic fields (EMFs) have been known to be able to improve bone health; however, their optimal application parameters and action mechanisms remain unclear. This study compared the effects of different forms of EMFs (sinusoidal, triangular, square, and serrated, all set at 50 Hz frequency and 1.8 mT intensity) on proliferation, differentiation and mineralization of rat calvarial osteoblasts. Square EMFs stimulated osteoblast proliferation but sinusoidal EMFs inhibited it. Sinusoidal and triangular EMFs produced significantly greater alkaline phosphatase (ALP) activity, ALP staining areas, calcium deposition, mineralized nodule areas, and mRNA expression of Runx-2, osteoprotegerin and insulin-like growth factor-I than square and serrated EMFs (P < 0.01). Triangular EMFs had a greater effect than sinusoidal EMFs on every indices except for Runx-2 mRNA expression (P < 0.05). These results indicated that while square EMFs promoted proliferation and had no effect on the differentiation of osteoblasts, sinusoidal EMFs inhibited proliferation but enhanced osteogenic differentiation. Triangular EMFs did not affect cell proliferation but induced the strongest osteogenic activity among the four waveforms of EMFs. Thus, the effects of EMFs on proliferation and differentiation of osteoblasts in vitro were dependent on their waveforms.


Assuntos
Calcificação Fisiológica/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Campos Eletromagnéticos , Osteoblastos/efeitos da radiação , Fosfatase Alcalina/metabolismo , Animais , Animais Recém-Nascidos , Calcificação Fisiológica/fisiologia , Cálcio/metabolismo , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Osteoblastos/fisiologia , Osteogênese/fisiologia , Osteogênese/efeitos da radiação , Osteoprotegerina/metabolismo , RNA Mensageiro/metabolismo , Ratos Wistar
19.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 36(6): 660-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25556743

RESUMO

OBJECTIVE: To investigate the effect of 50 Hz 0.1 mT sinusoidal electromagnetic field at different time points on bone mineral density(BMD)and histomorphometry in rats. METHODS: Totally 50 6-week-old female SD rats were equally randomized into 5 groups: control group,45-minute group,90-minute group,180-minute group,and 270-minute group. Except for the control group,the other four groups were given magnetic intervention in the 50-Hz 0.1-mT sinusoidal electromagnetic field for 45 minutes,90 minutes,180 minutes,or 270 minutes,respectively,on a daily basis. After 8 weeks,the total body BMD,femur BMD,and vertebral BMD were measured by dual-energy X-ray absorptiometry. The left tibia and the fifth lumbar vertebrae were separated for bone tissue static and dynamic analyses. RESULTS: Compared with control group,the 90-minute group and the 180-minute group had significantly different total body BMD(P<0.01,P<0.05),while no such significant difference was seen in the 45-minute group and 270-minute group (P>0.05). The femur,vertebral BMD,serum biochemical markers,and the static parameters of the fifth lumbar vertebrae tissue showed significant differences in the 90-minute group,180-minute group,and 270-minute group(P<0.01),but not in the 45-minute group (P>0.05). As shown by double fluorescent labeling,the distance was sorted in an order of 90-minute group>180-minutes group>270-minute group>45-minutes group>control group. CONCLUSION: The 50-Hz 0.1-mT sinusoidal electromagnetic field can effectively increase bone mineral density and improve bone morphology;however,the intervention effectiveness differs at different time points,with the best effectiveness seen at 90 minutes.


Assuntos
Densidade Óssea , Campos Eletromagnéticos , Absorciometria de Fóton , Animais , Osso e Ossos , Feminino , Fêmur , Vértebras Lombares , Ratos , Ratos Sprague-Dawley , Tíbia
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 35(5): 542-6, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24183044

RESUMO

OBJECTIVE: To compare the effects of icariin (ICA) and genistein (GEN) on rats bone peak mass and thus screen for a drug that can more effectively prevent osteoporosis. METHODS: Totally 36 one-month SD rats were randomly divided into three groups: ICA group [25 mg/(kg·d), intragastric administration], GEN group [10 mg/(kg·d), intragastric administration], and control group (fed with equal volume of distilled water). The body weight was monitored weekly and the bone mineral density of total body was measured monthly. All rats were sacrificed three months later. The femoral bone mineral density and the serum levels of osteocalcin and anti-tartaric acid phosphatase 5b, N-terminal propeptide of type 1 procollagen, and C-terminal propeptide of type 1collagen were measured. The bone microarchitectures were analyzed with micro-CT and the bone biomechanics properties were tested with universal material machine. RESULTS: The body weight and organ index showed no significant difference among these three groups(P>0.05). No obvious pathological change was found. The bone mineral density was also not significantly different in the first and second months; however, in the third months, the ICA group had significant higher bone mineral density for both total body and femur than those in the control and GEN group (P<0.05). The same trends were found for both femur bone mineral density and whole-body bone mineral density (P<0.05). The ICA group also had significantly higher serum levels of osteocalcin (P<0.05) and lower level of anti-tartaric acid phosphatase 5b(P<0.05). Besides, rats in the ICA group had significantly larger bone volume/tissue volume, trabecular thickness, and trabecular number than the control group, whereas the trabecular spacing and model coefficients were signicantly lower(all P<0.05), which, however, were not significantly different between ICA group and GEN group (P>0.05). Femoral maximum load, Youg's modulus, and yield load were significantly higher in these two groups than in the control group (P<0.05), which, again, were not significantly different between ICA group and GEN group (P>0.05). CONCLUSION: Orally administered ICA is more efficient than GEN in inhibiting resorption and promoting bone formation, and thus can dramatically improve the peak bone mineral density and bone quality.


Assuntos
Densidade Óssea/efeitos dos fármacos , Flavonoides/farmacologia , Genisteína/farmacologia , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Feminino , Osteoporose/prevenção & controle , Ratos , Ratos Sprague-Dawley
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