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1.
Pharm Biol ; 58(1): 146-151, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31971852

RESUMO

Context: Oridonin exhibits various pharmacological and physiological activities, including antioxidant, antibacterial, anti-inflammatory, pro-apoptotic, anticancer and neurological effects. However, its role in rheumatoid arthritis (RA) is yet to be revealed.Objective: We evaluated the effects of oridonin on the survival and autophagy of RA-fibroblast-like synoviocytes (FLSs).Materials and methods: RA-FLSs were treated with oridonin at serial concentrations of 0, 2, 4, 6, 8 and 10 µg/mL for 24, 48 and 72 h. Then, cell proliferation and apoptosis were measured. A GFP-LC3 plasmid was transfected into the cells to determine autophagy.Results: Oridonin suppressed RA-FLS proliferation in a dose-dependent manner. The half maximal inhibitory concentrations (IC50) of oridonin at 24, 48 and 72 h were 8.28, 7.88 and 8.35 µg/mL, respectively. Treatment with oridonin for 24 h increased apoptosis by 4.1%, and increased the protein levels of Bax and cleaved caspase-3 but significantly decreased the levels of IL-1ß in the culture supernatant (p < 0.05). In addition, 6 h of oridonin treatment significantly decreased the number of GFP-LC3 punctate dots and inhibited the protein levels of ATG5 and Beclin1 by 80.01% and 42.12%, respectively. Chloroquine (CQ) significantly reinforced the effects of oridonin on inhibition of autophagy, suppression of proliferation, and induction of apoptosis in RA-FLSs (p < 0.05).Conclusions: Our results indicate that treatment with oridonin in combination with CQ inhibits autophagy and cell proliferation and induces apoptosis in RA-FLSs more effectively than treatment oridonin alone. This finding indicates that oridonin is a potential therapeutic agent for RA.

2.
ACS Appl Mater Interfaces ; 12(4): 4815-4820, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31898447

RESUMO

Taking the advantages of excellent optical properties, biocompatibility, and photostability of carbon dots, herein, we developed polarity-sensitive polymer carbon dots (PCDs) for visualizing of cellular polarity to real-time monitoring autophagy changes without perturbing the cellular status. The PCDs can be prepared by simply mixing dopamine (DA), H2O2, and o-phenylenediamine (o-PDA) in a common beaker without the need for any special equipment or external energy supply, and the preparation could be completed within 3 min at room temperature. Interestingly, the polarity-sensitive PCDs could emit various types of fluorescence and are insensitive to the excitation light when dispersed in different water/dioxane systems with different polarities. Based on the polarity-sensitive emission of the PCDs, the change of polarity during autophagy has been successfully monitored in living cells. Moreover, the change of polarity detected by PCDs is autophagy-specific (does not occur during apoptosis), occurs under different autophagy-inducing situations (starvation, rapamycin, and trehalose), and requires a normal autophagic flux, showing that PCDs rapidly prepared by polymerization cross-linking at room temperature can be functionally applied in the case of autophagy-related physiological or pathological processes.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31820689

RESUMO

BACKGROUND: Melittin, the major medicinal component of honeybee venom, exerts anti-inflammatory, analgesic, and anti-arthritic effects in patients with rheumatoid arthritis (RA). Melittin has hormone-like effects but no hormone-like side effects. RA is an inflammatory autoimmune joint disease that leads to irreversible joint destruction and functional loss. Fibroblast-like synoviocytes (FLS) are dominant, special mesenchymal cells characterized by the structure of the synovial intima, playing a crucial role in both the initiation and progression of RA. OBJECTIVE: In this study, we evaluated the effects of melittin on the viability and apoptosis of FLS isolated from patients with RA. METHOD: Cell viability was determined using CCK-8 assays; apoptosis was evaluated by flow cytometry, and the expression levels of apoptosis-related proteins (caspase-3, caspase-9, BAX, and Bcl-2) were also determined. To explore whether melittin alters inflammatory processes in RA-FLS, IL-1ß levels were determined using an enzyme-linked immunosorbent assay (ELISA). Furthermore, we performed GFP-LC3 punctate fluorescence dot assays and western blotting (for LC3, ATG5, p62, and Beclin 1) to assess autophagy in RA-FLS. RESULTS: Our results show that melittin can significantly impair viability, promote apoptosis and autophagy, and inhibit IL-1ß secretion in RA-FLS. CONCLUSION: Melittin may be useful in preventing damage to the joints during accidental local stimulation.

4.
Technol Cancer Res Treat ; 18: 1533033819851833, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31570091

RESUMO

OBJECTIVE: To investigate the role of miR-26a-5p in cell proliferation and doxorubicin sensitivity in hepatocellular carcinoma. METHODS: We evaluated miR-26a-5p expression in hepatocellular carcinoma tissues and cell lines by reverse transcription polymerase chain reaction. Cell Counting Kit-8 was used to examine cell proliferation. Relationship between miR-26a-5p and aurora kinase A was evaluated by luciferase report system. Western blot was used to detect expression of aurora kinase A. RESULTS: In this study, we observed miR-26a-5p was downregulated in hepatocellular carcinoma tissues and cell lines. Gain-of-function experiments showed that proliferation rate of hepatocellular carcinoma cells decreased under condition of miR-26a-5p mimics. We found miR-26a-5p mimics could enhance doxorubicin sensitivity of hepatocellular carcinoma cells. Further study showed that aurora kinase A was target gene of miR-26a-5p. Suppression of aurora kinase A could lead to lower cell proliferation and higher doxorubicin sensitivity of hepatocellular carcinoma cells. CONCLUSION: Our study found that miR-26a-5p could inhibit cell proliferation and enhance doxorubicin sensitivity in hepatocellular carcinoma cells by targeting aurora kinase A.


Assuntos
Aurora Quinase A/genética , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , MicroRNAs/genética , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Panminerva Med ; 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31290300

RESUMO

OBJECTIVE: Emerging evidences suggest that metformin has a potential antitumor effect both in vitro and in vivo. Increasing epidemiological studies indicate that diabetic patients receiving metformin therapy have lower incidences of cancer and have better survival rates. However, there are limited and inconsistent studies available about the effect of metformin therapy on ovarian cancer (OC). Thus, we conducted this meta-analysis to study the effect of metformin therapy on OC. Meanwhile, we systematically reviewed relevant studies to provide a framework for future research. RESEARCH DESIGN AND METHODS: We conducted a systematic literature search on PubMed, Web of Science, Springerlink, CNKI, VIP, SinoMed, and Wanfang up to the period of October 2018. A random-effects meta-analysis model was used to derive pooled effect estimates. RESULTS: A total of 13 studies were retrieved of which 5 studies explained the prevention and 8 studies explained the treatment for OC. Our pooled results showed that metformin has a potential preventive effect on OC in diabetic women [pooled odds ratio (OR) 0.62, 95% confidence interval (95% CI) 0.34, 1.11; P<0.001]. In addition, metformin can also significantly prolong progression-free survival (PFS) [pooled hazard ratio (HR) 0.49, 95% CI 0.34, 0.70; P=0.002], and overall survival (OS) [HR 0.71, 95%CI 0.61, 0.82; P<0.001] in patients with OC, regardless of whether they had diabetes. CONCLUSIONS: The use of metformin can potentially reduce the risk of OC among diabetics, and it also can significantly improve PFS and OS in patients with OC. A further large clinical investigation would be needed to adopt our finding in practice, however, our systematic review provides an insight for future study designs.

6.
Urol J ; 16(4): 347-351, 2019 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-30882174

RESUMO

PURPOSE: This study aims to evaluate the value of quantitative analysis of ultrasound real-time tissue diffusion elastography in the diagnosis of benign and malignant prostate lesions. MATERIALS AND METHODS: From March 2010 to June 2013, 52 patients suspected with prostate cancer based on laboratory or clinical test results and underwent prostate biopsy in our hospital were enrolled into this study. The age of these patients ranged between 45-82 years, with an average age of 67.2 ± 6.8 years. All patients underwent transrectal real-time ultrasound elastography (TRTE) before biopsy. A total of 63 prostate nodules were detected, and the 11 elastic characteristic quantities of these nodules were quantitatively analyzed via tissue diffusion quantitative analysis. The results of ultrasonography were compared with the results of operation and pathology. RESULT: Among these 11 characteristic quantities, which include the mean (MEAN) and standard deviation (SD), blue area ratio (AREA%), complexity (COMP), kurtosis (KURT), skewness (SKEW), contrast (CONT), equality (ENT), entropy (IDM), consistency (ASM) and correlation (CORR), except for COMP and CORR, the differences in other nine characteristic quantities between benign and malignant prostatic nodules were statistically significant (P<0.05). Among these, the AREA% and MEAN had the highest correlation, which were 0.791 and -0.791, respectively. The Youden's index (sensitivity and specificity) of AREA% in the ROC curves was the highest, the cutoff value was 80.65% for the diagnosis of prostate cancer, sensitivity was 87.9%, and specificity was 96.6%. CONCLUSION: Quantitative analysis of ultrasound real-time tissue diffusion elastography is helpful in the diagnosis of benign and malignant prostate lesions, provides a relatively accurate evaluation method in clinical practice, and has broad application prospects.


Assuntos
Técnicas de Imagem por Elasticidade , Doenças Prostáticas/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Estudos de Avaliação como Assunto , Humanos , Masculino , Pessoa de Meia-Idade
7.
Oncol Rep ; 41(3): 1649-1657, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30592290

RESUMO

The present study investigated the expression and potential influence of SHC SH2 domain­binding protein 1 (SHCBP1) in gastric cancer (GC) cells. SHCBP1 is closely related to cell proliferation and cell cycle progression, but its role in GC remains unclear. The TCGA database revealed that SHCBP1 is highly expressed in GC tissues. Furthermore, SHCBP1 was revealed to be highly expressed in GC cell lines MGC­803 and SGC­7901 cells, and downregulation of SHCBP1 significantly inhibited GC cell proliferation. Furthermore, SHCBP1 expression promoted cell cycle progression and inhibition of apoptosis. Since the CDK4, cyclin D1 and caspase family proteins play important roles in cell cycle and apoptosis regulation, it was examined whether there was an association between SHCBP1 and these signaling pathways in GC. Our results revealed that SHCBP1 promoted cell cycle progression by regulating the CDK4­cyclin D1 cascade and suppressed caspase­3, caspase PARP­dependent apoptotic pathways. Cell invasion and metastasis experiments also revealed that SHCBP1 promoted tumor growth and invasiveness. These tumor­promoting functions of SHCBP1 may provide a potential molecular basis for the diagnosis and targeted therapy of GC.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Neoplasias Gástricas/patologia , Apoptose , Biomarcadores Tumorais/genética , Caspase 3/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , RNA Interferente Pequeno/metabolismo , Proteínas Adaptadoras da Sinalização Shc/genética , Transdução de Sinais , Estômago/patologia , Neoplasias Gástricas/diagnóstico
8.
Surg Laparosc Endosc Percutan Tech ; 26(3): e69-72, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27258919

RESUMO

OBJECTIVE: To evaluate the feasibility and safety of laparoscopic liver resection in obese patients, we compared the operative outcomes between obese and nonobese patients, also between laparoscopic liver resection and open liver resection of obese and nonobese patients. MATERIALS AND METHODS: A total of 86 patients suffering from liver resection in our department from January 2013 to December 2014 were divided into 3 groups: the obese patients group for laparoscopic liver resection, the nonobese patients group for laparoscopic liver resection and the obese patients group for open liver resection. Characteristics and clinic data of 3 groups were studied. RESULTS: Characteristics of patients and clinic data were equivalent between the 3 groups. The groups were well matched in age, sex distribution, and liver function (P>0.05). There were no significant differences in the operative time, estimated blood loss, time to oral intake, and postoperative hospital stay in the 3 groups. Tumor diameter of laparoscopic liver resection groups in obese patients was smaller than open liver resections groups in obese patients (P<0.05), but there were no obvious difference of tumor diameter in the laparoscopic liver resection groups of the obese patients and the nonobese patients. CONCLUSIONS: Obesity should not be seen as a contraindication for laparoscopic liver resection, which is a safe and feasible procedure for obese patients.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hemangioma Cavernoso/cirurgia , Laparoscopia/métodos , Neoplasias Hepáticas/cirurgia , Obesidade/complicações , Perda Sanguínea Cirúrgica , Estudos de Viabilidade , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos , Resultado do Tratamento
9.
Surg Laparosc Endosc Percutan Tech ; 25(5): e145-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26429056

RESUMO

OBJECTIVE: To evaluate the feasibility and safety of laparoscopic versus open resection for liver cavernous hemangioma (LCH). MATERIALS AND METHODS: A total of 131 patients suffering from LCH operated in our department between January 2013 and December 2014 were divided into 2 groups: 31 for laparoscopic liver resection (LR) and 100 for open liver resection (OR). RESULTS: Age, sex, presence or absence of chronic liver disease, tumor size, tumor location, type of resection, estimated intraoperative blood loss, operative time, length of postoperative hospital stay, morbidity, and mortality were equivalent between the 2 groups. There were no significant differences in estimated intraoperative blood loss between the LR and OR groups. The operation time of the LR group was longer than the OR group and the hospitalization expenses less than the OR group. However, the time of postoperative hospital stay and time of oral intake were shorter in the LR group than the OR group. The tumor of the LR group was smaller than the OR group. In liver function, alanine aminotransferase after operation of the LR group was lower than the OR group, the same as aspartate transaminase after operation. But there were no significant differences in total bilirubin after operation. CONCLUSIONS: Laparoscopic resection for LCH is a safe and feasible procedure as OR.


Assuntos
Hemangioma Cavernoso/cirurgia , Hepatectomia/métodos , Laparoscopia/métodos , Laparotomia/métodos , Neoplasias Hepáticas/cirurgia , Feminino , Seguimentos , Hemangioma Cavernoso/diagnóstico , Humanos , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
CNS Neurosci Ther ; 21(10): 826-36, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26122409

RESUMO

AIMS: Automated hippocampal segmentation is an important issue in many neuroscience studies. METHODS: We presented and evaluated a novel segmentation method that utilized a manifold learning technique under the multiatlas-based segmentation scenario. A manifold representation of local patches for each voxel was achieved by applying an Isomap algorithm, which can then be used to obtain spatially local weights of atlases for label fusion. The obtained atlas weights potentially depended on all pairwise similarities of the population, which is in contrast to most existing label fusion methods that only rely on similarities between the target image and the atlases. The performance of the proposed method was evaluated for hippocampal segmentation and compared with two representative local weighted label fusion methods, that is, local majority voting and local weighted inverse distance voting, on an in-house dataset of 28 healthy adolescents (age range: 10-17 years) and two ADNI datasets of 100 participants (age range: 60-89 years). We also implemented hippocampal volumetric analysis and evaluated segmentation performance using atlases from a different dataset. RESULTS: The median Dice similarities obtained by our proposed method were approximately 0.90 for healthy subjects and above 0.88 for two mixed diagnostic groups of ADNI subjects. CONCLUSION: The experimental results demonstrated that the proposed method could obtain consistent and significant improvements over label fusion strategies that are implemented in the original space.


Assuntos
Doença de Alzheimer/patologia , Atlas como Assunto , Hipocampo/anatomia & histologia , Hipocampo/patologia , Aprendizado de Máquina , Imagem por Ressonância Magnética/métodos , Adolescente , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade
11.
Chin Med J (Engl) ; 128(8): 1042-6, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25881597

RESUMO

BACKGROUND: The cause of the adjacent segment degeneration (ASD) after fusion remains unknown. It is reported that adjacent facet joint stresses increase after anterior cervical discectomy and fusion. This increase of stress rate may lead to tissue injury. Thus far, the load rate of the adjacent segment facet joint after fusion remains unclear. METHODS: Six C2-C7 cadaveric spine specimens were loaded under four motion modes: Flexion, extension, rotation, and lateral bending, with a pure moment using a 6° robot arm combined with an optical motion analysis system. The Tecscan pressure test system was used for testing facet joint pressure. RESULTS: The contact mode of the facet joints and distributions of the force center during different motions were recorded. The adjacent segment facet joint forces increased faster after fusion, compared with intact conditions. While the magnitude of pressures increased, there was no difference in distribution modes before and after fusion. No pressures were detected during flexion. The average growth velocity during extension was the fastest and was significantly faster than lateral bending. CONCLUSIONS: One of the reasons for cartilage injury was the increasing stress rate of loading. This implies that ASD after fusion may be related to habitual movement before and after fusion. More and faster extension is disadvantageous for the facet joints and should be reduced as much as possible.


Assuntos
Fusão Vertebral/efeitos adversos , Coluna Vertebral/fisiopatologia , Fenômenos Biomecânicos , Humanos , Técnicas In Vitro , Vértebras Lombares/fisiopatologia , Amplitude de Movimento Articular/fisiologia
12.
Connect Tissue Res ; 56(2): 99-105, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25602512

RESUMO

OBJECTIVES: To observe the age-related changes of sulfated glycosaminoglycan (sGAG) content of hip joint cartilage of elderly people based on Equilibrium Partitioning of an Ionic Contrast Agent (EPIC) micro-CT. METHODS: Seventy human hip cartilage-bone samples were collected from hip-fracture patients (ages 51-96) and divided into five groups (10 years in an age group). They were first immersed in 20% concentration of the contrast agent Meglumine Diatrizoate (MD) for 6 h at 37 °C, and then scanned by micro-CT. Following scanning, samples were stained for sGAG with toluidine blue. The X-ray attenuation and sGAG optical density were calculated by image processing. The correlation between X-ray attenuation and sGAG optical density was then analyzed. RESULTS: The X-ray mean attenuation of the cartilage increased by 18.81% from the 50-80 age groups (p < 0.01), but decreased by 7.15% in the 90 age group compared to the 80 age group. The X-ray mean attenuation of the superficial layer and middle layer increased by 31.60 % and 44.68% from the 50-80 age groups, respectively (p < 0.01), but reduced by 4.67% and 6.05% separately in the 90 age group. However, the deep layer showed no significant change with aging. The sGAG optical density showed a linear correlation (r = -0.91, p < 0.01) with the X-ray attenuation. CONCLUSION: The sGAG content of hip joint cartilage varied with aging in elderly people. The changes in superficial layer and middle layer were more evident than deep layer.


Assuntos
Cartilagem Articular/patologia , Glicosaminoglicanos/metabolismo , Articulação do Quadril/patologia , Osteoartrite do Quadril/patologia , Microtomografia por Raio-X , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Humanos , Pessoa de Meia-Idade , Microtomografia por Raio-X/métodos
13.
Ying Yong Sheng Tai Xue Bao ; 25(3): 738-44, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24984491

RESUMO

The profile distribution and accumulation characteristics of organic carbon of four typical marshes (herbaceous peat, marsh wetland, mountain wetland, subalpine meadow) were studied in Gahai Wetlands of Gannan in July 2011. The results showed that the soil bulk densities of the four typical marshes ranged from 0.22 to 1.29 g x cm(-3). The content of soil organic carbon in the herbaceous peat was higher than in other types, with its average content of organic carbon (286. 80 g x kg(-1)) being about 2.91, 4.99, 7.31 times as much as that of the marsh wetland, mountain wetland and subalpine meadow, respectively. The average organic carbon densities were in order of herbaceous peat > subalpine meadow > marsh wetland > mountain wetland, with the highest in the 0-10 cm layer. The change of organic carbon density along the soil profile was basically in accordance with the organic carbon content in the four typical marshes, but fluctuated with soil depth. There were obviously two carbon storage layers (0-10 and 20-40 cm, respectively) in the four typical marshes. The amounts of organic carbon stored in the 0-60 cm layer of the four typical marshes were 369.46, 278.83, 276.16, 292.23 t x hm(-2), respectively. The total amount of organic carbon stored in the 0-60 cm of the four typical marshes was about 9.50 x 10(6) t.


Assuntos
Ciclo do Carbono , Carbono/análise , Solo/química , Áreas Alagadas , China , Pradaria
14.
Sci China Life Sci ; 57(10): 1034-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24771062

RESUMO

In previous research, time-delay (Δt) was a more important parameter than the reflection coefficient in the individual transfer function of central aortic pressure reconstruction. The Δt can be obtained by electrocardiography (ECG) or phonocardiography (PCG). Because the pre-ejection period remains an uncertain factor, the present study used ECG and PCG to define the delay time and analyzed the accuracy of the reconstruction results. The Δt pre is the actual delay time derived from the aorta to the carotid pressure wave, Δt PCG is the time delay between the aortic valve component of the second heart sound and the dicrotic incisura of the carotid pressure wave, and Δt ECG represents the delay from the interval of the ECG R-peak to the foot of the carotid pressure wave. Compared with the measured aortic pressure, the reconstruction result obtained by Δt=Δt PCG slightly differed from the best result estimated by Δt=Δt pre. However, the differences between the result obtained by Δt=Δt ECG and the best result were significant in terms of the diastolic blood pressure, and pulse pressure, and especially in terms of the augmentation index and root-mean-square-error. Thus, the Δt should be determined by PCG for central aortic pressure reconstruction in practice.


Assuntos
Aorta/patologia , Eletrocardiografia/métodos , Fonocardiografia/métodos , Animais , Pressão Arterial , Pressão Sanguínea , Artérias Carótidas/patologia , Ruídos Cardíacos , Valvas Cardíacas/patologia , Modelos Teóricos , Pulso Arterial , Processamento de Sinais Assistido por Computador , Suínos , Fatores de Tempo
15.
Biomed Mater Eng ; 24(1): 191-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24211898

RESUMO

UNLABELLED: The internal hydrostatic pressure (IHP) of the intervertebral disc is the functional and physiological basis of the spine. Disc bulging is a direct effect of increased IHP and can be used to evaluate the IHP without destroying the structure of the disc. Disc tissue engineering is a developing field but more data on the properties of normal discs are required for evaluation of possible graft materials. However, very little data is available concerning bulge distribution along the normal disc surface under creep. METHODS: Fifteen motion segment specimens of ovine IVD were used to analyze axial creep, and disc bulging deformations of 5 markers on the surface were measured and analyzed. FINDINGS: The maximum radial bulging rate was 2.78%± 1.09% and the position at which the maximum radial deformation occurred was found to be below the midline of the disc during all levels of loading. The results showed that deformations occurred in the order vertical, radial, circumferential. INTERPRETATION: Disc bulging during creep is a very important biomechanical response, affecting spinal functions. The deformation regularities of the disc surface were identified and may help supply important basic data for disc tissue engineering.


Assuntos
Deslocamento do Disco Intervertebral/fisiopatologia , Disco Intervertebral/fisiopatologia , Animais , Fenômenos Biomecânicos , Elasticidade , Pressão Hidrostática , Vértebras Lombares/patologia , Movimento (Física) , Ovinos , Coluna Vertebral , Estresse Mecânico , Vértebras Torácicas/patologia , Engenharia Tecidual
16.
Biomed Res Int ; 2013: 714103, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24383057

RESUMO

The intervertebral disc degeneration and injury are the most common spinal diseases with tremendous financial and social implications. Regenerative therapies for disc repair are promising treatments. Fiber-reinforced materials (FRMs) are a kind of composites by embedding the fibers into the matrix materials. FRMs can maintain the original properties of the matrix and enhance the mechanical properties. By now, there are still some problems for disc repair such as the unsatisfied static strength and dynamic properties for disc implants. The application of FRMs may resolve these problems to some extent. In this review, six parts such as background of FRMs in tissue repair, the comparison of mechanical properties between natural disc and some typical FRMs, the repair standard and FRMs applications in disc repair, and the possible research directions for FRMs' in the future are stated.


Assuntos
Materiais Biocompatíveis , Degeneração do Disco Intervertebral/cirurgia , Disco Intervertebral/lesões , Próteses e Implantes , Medicina Regenerativa/métodos , Animais , Humanos , Disco Intervertebral/cirurgia
17.
Sci China Life Sci ; 55(5): 444-51, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22645088

RESUMO

The purpose of this study was to explore the triphasic mechanical properties of osteoarthritic cartilage with different pathological grades. First, samples of cartilage from rabbits with different stages of osteoarthritis (OA) were graded. Following this, the cartilage was strained by a swelling experiment, and changes were measured using a high-frequency ultrasound system. The result, together with fixed charge density and water volume fraction of cartilage samples, was used to estimate the uniaxial modulus of the cartilage tissue, based on a triphasic model. For the control cartilage samples, the uniaxial elastic modulus on the cartilage surface was lower than those in the middle and deep layers. With an increase in the OA grade, the uniaxial elastic modulus of the surface, middle and deep layers decreased. A significant difference was found in the surface elastic modulus of different OA grades (P<0.01), while no significant differences were identified for OA cartilages of Grades 1 and 2 in the middle and deep layers (P<0.01). Compared with Grades 1 and 2, there was a significant reduction in the elastic modulus in the middle and deep layers of Grade 3 OA cartilage (P<0.05). Overall, this study may provide a new quantitative method to evaluate the severity of OA using the mechanical properties of cartilage tissue.


Assuntos
Cartilagem Articular/fisiologia , Osteoartrite/fisiopatologia , Animais , Teste de Materiais , Modelos Teóricos , Coelhos
18.
BMC Musculoskelet Disord ; 13: 70, 2012 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-22584084

RESUMO

BACKGROUND: Physical loading leads to a deformation of bone microstructure and may influence quantitative ultrasound (QUS) parameters. This study aims at evaluating the effect of physical loading on bone QUS measurement, and further, on the potential of diagnosing osteoporosis using QUS method under physical loading condition. METHODS: 16 healthy young females (control group) and 45 postmenopausal women (divided into 3 groups according to the years since menopause (YSM)) were studied. QUS parameters were measured at calcaneus under self-weight loading (standing) and no loading (sitting) conditions. Weight-normalized QUS parameter (QUS parameter measured under loading condition divided by the weight of the subject) was proposed to evaluate the influence of loading. T-test, One-Way analysis of variance (one way ANOVA) and receiver operating characteristic (ROC) analysis were applied for analysis. RESULTS: In QUS parameters, mainly normalized broadband ultrasound attenuation (nBUA), measured with loading significantly differed from those measured without loading (p < 0.05). The relative changes of weight-normalized QUS parameters on postmenopausal women with respect to premenopausal women under loading condition were larger than those on traditional QUS parameters measured without loading. In ROC analysis, weight-normalized QUS parameters showed their stronger discriminatory ability for menopause. CONCLUSIONS: Physical loading substantially influenced bone QUS measurement (mainly nBUA). Weight-normalized QUS parameters can discriminate menopause more effectively. By considering the high relationship between menopause and osteoporosis, an inference was drawn that adding physical loading during measurement may be a probable way to improve the QUS based osteoporosis diagnosis.


Assuntos
Calcâneo/diagnóstico por imagem , Osteoporose Pós-Menopausa/diagnóstico por imagem , Ultrassonografia/métodos , Suporte de Carga/fisiologia , Adulto , Fatores Etários , Idoso , Calcâneo/patologia , Calcâneo/fisiologia , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/patologia , Pós-Menopausa , Valor Preditivo dos Testes , Curva ROC , Estresse Mecânico , Adulto Jovem
19.
BMC Musculoskelet Disord ; 13: 34, 2012 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-22405078

RESUMO

BACKGROUND: Early diagnosis of osteoarthritis (OA) is essential for preventing further cartilage destruction and decreasing severe complications. The aims of this study are to explore the relationship between OA pathological grades and quantitative acoustic parameters and to provide more objective criteria for ultrasonic microscopic evaluation of the OA cartilage. METHODS: Articular cartilage samples were prepared from rabbit knees and scanned using ultrasound biomicroscopy (UBM). Three quantitative parameters, including the roughness index of the cartilage surface (URI), the reflection coefficients from the cartilage surface (R) and from the cartilage-bone interface (Rbone) were extracted. The osteoarthritis grades of these cartilage samples were qualitatively assessed by histology according to the grading standards of International Osteoarthritis Institute (OARSI). The relationship between these quantitative parameters and the osteoarthritis grades was explored. RESULTS: The results showed that URI increased with the OA grade. URI of the normal cartilage samples was significantly lower than the one of the OA cartilage samples. There was no significant difference in URI between the grade 1 cartilage samples and the grade 2 cartilage samples. The reflection coefficient of the cartilage surface reduced significantly with the development of OA (p < 0.05), while the reflection coefficient of the cartilage-bone interface increased with the increase of grade. CONCLUSION: High frequency ultrasound measurements can reflect the changes in the surface roughness index and the ultrasound reflection coefficients of the cartilage samples with different OA grades. This study may provide useful information for the quantitative ultrasonic diagnosis of early OA.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Microscopia Acústica , Osteoartrite do Joelho/diagnóstico por imagem , Animais , Cartilagem Articular/patologia , Modelos Animais de Doenças , Diagnóstico Precoce , Feminino , Articulação do Joelho/patologia , Osteoartrite do Joelho/patologia , Valor Preditivo dos Testes , Coelhos , Índice de Gravidade de Doença , Propriedades de Superfície
20.
Sci China Life Sci ; 54(11): 1029-35, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22173309

RESUMO

Subtle changes of articular cartilage (AC) can lead to tissue degeneration and even osteoarthritis (OA). The early degeneration of AC is closely related to a change in proteoglycans (PG) content. The observation of PG is therefore an appropriate way of studying OA and evaluating the degree of AC degeneration. In this study, 20 cartilage-bone samples were prepared from normal porcine femoral condyle cartilage and 10 samples were digested over 2 h using 0.25% trypsin solution. The dynamic process of PG-digestion was explored using a conventional A-mode ultrasound (US) experimental system with a 10 MHz center frequency. Quantitative acoustic parameters were calculated from ultrasonic radio-frequency echo signals and included US speed (USS), US amplitude attenuation coefficient (UAA) and broadband US attenuation coefficient (BUA). The experimental results showed that the conventional A-mode ultrasound is valuable for tracking the degree of PG-digestion. Histology also confirmed the validity of the ultrasound observations. For every AC sample, the degree of PG-digestion within a given time was different and was affected by individual differences. After two hours of degeneration, USS showed a mean decrease of 0.4% (P<0.05). UAA was significantly lower after a two-hour PG depletion period (from (2.45±0.23) to (2.28±0.41) dB mm⁻¹). BUA showed no significant differences during this process. In conclusion, conventional ultrasound can provide useful information about trypsin-induced progressive PG depletion in AC and can reflect variations of PG content via the quantitative acoustic parameters USS and UAA. The results of this study may be used to identify an indirect indicator of cartilage matrix integrity and OA disease progression.


Assuntos
Cartilagem Articular/química , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Tripsina/química , Tripsina/metabolismo , Ultrassom/métodos , Animais , Humanos , Osteoartrite/diagnóstico por imagem , Osteoartrite/patologia , Proteoglicanas/análise , Suínos , Ultrassonografia
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