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1.
Eur Rev Med Pharmacol Sci ; 22(20): 6816-6823, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30402845

RESUMO

OBJECTIVE: To detect the expression of microRNA-556-3p in esophageal cancer (EC) tissues and to elucidate the mechanisms underlying microRNA-556-3p in promoting EC progression. PATIENTS AND METHODS: QRT-PCR (quantitative Real-Time Polymerase Chain Reaction) was performed to detect microRNA-556-3p expression in 65 cases of EC tissues, 30 cases of normal esophageal tissues and EC cell lines. The overall survival (OS) of EC patients was calculated based on the 10-year follow-up data. For in vitro experiments, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and transwell assay were performed to evaluate the effect of microRNA-556-3p on the proliferative and invasive abilities of EC cells. The effect of microRNA-556-3p on DAB2IP and MAPK pathway was determined by Western blot and qRT-PCR. The binding condition between microRNA-556-3p and DAB2IP was further confirmed by Luciferase reporter gene assay. RESULTS: MicroRNA-556-3p expression was upregulated in EC tissues than that of paracancerous tissues. EC patients with higher expression of microRNA-556-3p presented a shorter OS than those with lower expression. Moreover, microRNA-556-3p overexpression in EC cells remarkably promoted cell viability. Upregulated microRNA-556-3p in Eca109 and Eca7906 cell lines markedly increased cell proliferation and invasion. The expression level of DAB2IP was negatively regulated by microRNA-556-3p verified by the Luciferase reporter gene assay. CONCLUSIONS: MicroRNA-556-3p blocked the translation of DAB2IP at mRNA level by directly binding to 3'UTR of DAB2IP, thereafter enhancing the proliferation of Eca109 and Eca7906 cells. MicroRNA-556-3p promoted the occurrence and development of EC. Our study provided a new theoretical basis and therapeutic target for EC treatment.


Assuntos
Neoplasias Esofágicas/metabolismo , MicroRNAs/metabolismo , Proteínas Ativadoras de ras GTPase/metabolismo , Regiões 3' não Traduzidas , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Transdução de Sinais , Proteínas Ativadoras de ras GTPase/genética
2.
J Opt Soc Am A Opt Image Sci Vis ; 34(4): 498-505, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28375319

RESUMO

Wavelength calibration is an important step in charge-coupled device (CCD) spectrometers. In this paper, an accurate calibration method is proposed. A model of a line profile spectrum is built at the beginning, followed by noise reduction, bandwidth correction, and automatic peak-seeking treatment. Experimental tests are conducted on the USB4000 spectrometer with a mercury-argon calibration light source. Compared with the traditional method, the results show that this wavelength calibration procedure obtains higher accuracy and the deviations are within 0.1 nm.

3.
Clin Radiol ; 72(6): 517.e1-517.e6, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28292511

RESUMO

AIM: To determine the efficacy of dual Y-shaped covered airway stents to treat thoracic stomach-right main bronchus fistulae. MATERIAL AND METHODS: Fifteen patients who developed thoracic stomach-right main bronchus fistula after oesophageal cancer resection and postoperative irradiation were retrospectively analysed. All fistulae were close to the right upper lobe bronchus. Two Y-shaped covered airway stents were designed for each patient. Under radiographic guidance, one stent was placed from the right main bronchus into the bifurcation of upper lobe and intermediate bronchus, the other was placed from the trachea into both main bronchi. RESULTS: All fistulae were closed immediately after stenting. All patients could eat a semi-solid diet. The symptom of coughing while lying down resolved in all patients, and no complications, such as airway bleeding or pneumothorax, occurred. The average survival time was 26.65 months (range 2-40 months, 11 patients were still alive at the study end). Two patients died of tumour recurrence. Another two patients died of pulmonary infections. In one of these patients, there was a long delay between symptom onset and stenting. In the other patient, a small rupture occurred in the silicone membrane covering the stent, which allowed the leakage of gastric contents into the lung. CONCLUSION: Dual Y-shaped covered airway stent placement is feasible and safe to treat thoracic stomach-right main bronchus fistulae. Improvements to the material covering the stents is required.


Assuntos
Fístula Brônquica/cirurgia , Fístula Gástrica/cirurgia , Stents , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
4.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 31(19): 1496-1500;1503, 2017 Oct 05.
Artigo em Chinês | MEDLINE | ID: mdl-29798102

RESUMO

Objective:The purpose of this study was to produce chitosan nerve conduit in order to investigate the feasibility of chitosan nerve conduit combined with autologous platelet-rich plasma (PRP) for repairing facial nerve defects.Method:Forty New Zealand white rabbits were randomly divided into four groups (n=10 in each group).Establishment of the facial nerve defect model of the upper buccal branches was placed in the nerve regeneration catheter and injected with the same amount of PRP and saline. The PRP was injected into the chitosan nerve conduit as group A. The physiological saline was injected into the chitosan nerve conduit as group B. The physiological saline was injected into the silicone tube as group C. The PRP was injected into the silicone tube as group D. Eight weeks later,facial nerve gross observation,facial nerve electrophysiological tests,histological observation,image analysis,valuation of nerve regeneration recovery were detected.Result:Five patients were lost to follow up (all five in the modified Semont group),and three patients failed to complete treatment (all three in the Epley group). The sequelae at the 3rd day and one week after modified Semont maneuver were 27 and 9,while 41 and 15 in Epley group. The efficacy rates at the 3rd day and one week after modified Semont maneuver were 91.7% and 98.3%,and 91.9% and 96.8% in Epley group retrospectively. The sequelae and short-term effective rate of patients in modified Semont group was no difference when compared with that in Epley group (P>0.05).Conclusion:The chitosan nerve conduit combined with PRP has a certain effect on the repair of facial nerve defects and is expected to be applied to the repair of clinical facial nerve defects.


Assuntos
Quitosana , Traumatismos do Nervo Facial/tratamento farmacológico , Nervo Facial/fisiologia , Regeneração Nervosa/efeitos dos fármacos , Plasma Rico em Plaquetas , Animais , Nervo Facial/patologia , Doenças do Nervo Facial/terapia , Humanos , Coelhos
5.
Artigo em Chinês | MEDLINE | ID: mdl-29798408

RESUMO

Objective:To compare the clinical effect between partial superficial parotidectomy (PSP) and superficial parotidectomy (SP) through a retrospective analysis and to provide evidence for the benign tumor surgical strategy. Method:According to different surgical strategies performed, 168 patients with superficial parotid benign tumor were reviewed and divided into PSP group and SP group. Clinical data was compared between two groups from different aspects, including operation condition, complications, recurrence rate, as well as parotid function. SPSS 22.0 software was used in statistical analysis. Result:PSP group has an average operative incision length of (6.65±1.17)cm, and average operation time of (82.25±11.56)min, while SP group is (10.86±1.65)cm and (121.42±17.32)min. So, compared with the SP group, PSP has obvious advantages in operation conditions (P<0.01). Furthermore, PSP group also presents an advantage over SP group in occurrence of postoperative complications (P<0.05), while there is no significant difference between two groups in palindromia rate (P>0.05). As for the maintenance of parotid gland functions, PSP group could retain most of parotid functions, but no function would be retained in SP group. Statistical analysis confirms the significance (P<0.05). Conclusion: Compared with SP, in PSP there is declined complication incidence but no increased palindromia recurrence. However, PSP has an apparent advantage on decreased surgical incision length, downscaled operation scope, reduced operation time and retained original functions of gland. All these advantages present the reliability and feasibility of PSP in treating superficial parotid benign tumor.


Assuntos
Glândula Parótida/cirurgia , Neoplasias Parotídeas/cirurgia , Humanos , Recidiva Local de Neoplasia , Complicações Pós-Operatórias , Reprodutibilidade dos Testes , Estudos Retrospectivos
6.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 51(9): 566-9, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-27596349

RESUMO

The mode of dental antibacterial resin-based materials can be divided into two types, namely, single and combined antibacterial mode. With regard to single antibacterial mode, only one kind of antibacterial agent is added into the resin, which can be released or act as contacting antibacterial agent. The single mode resin has limitation in sterilization methods and effect. As for combined antibacterial mode, it is a combination of different types of biocides and thus maximizes the sterilizing effect, including the releasing antibacterial agent incorporated with the contacting antibacterial agent or antibacterial agents combined with calcium compound possessing biological mineralization function. In this paper, current status and further prospects of dental resin-based materials with antibacterial properties are reviewed from the perspectives of single and combined antibacterial modes to provide guidance for dental antibacterial resin material research.


Assuntos
Materiais Dentários/análise , Antibacterianos , Resinas Compostas , Materiais Dentários/química , Teste de Materiais , Resinas Sintéticas
7.
Genet Mol Res ; 14(3): 10007-14, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26345937

RESUMO

The current study was performed to investigate the effects of midazolam on immune function in pediatric patients after surgery and possible mechanism involved. Patients who needed sedation for more than 2 consecutive days after undergoing surgery in the Pediatric Surgery Department of our hospital were enrolled for the study. Fifty-six patients (5-14 years old) were randomly divided into midazolam and propofol treatment groups (N = 28 each in each group). Pediatric patients received midazolam or profolol via continuous intravenous administration, and their plasma cytokine levels were compared after 48 h. Cultured rat C6 brain glioma cells were pretreated with a range of concentrations of midazolam or propofol for 60 minutes prior to incubation with 10 ng/mL IL-1ß in serum-free medium or vehicle for 36 h. IL-6 concentration was subsequently measured using ELISA. In comparison with levels measured before the infusion of midazolam for 48 h, concentrations of all cytokines decreased, with the differences in IL-1ß, IL-8, and TNF-α concentrations reaching significance (all P < 0.05). Midazolam significantly suppressed the IL-1ß-induced release of IL-6 in rat C6 glioma cells. This inhibition was concentration-dependent between 0.3 and 3 µM, with 3 µM concentration of midazolam decreasing the IL-1ß-induced release of IL-6 by 43.58%. Midazolam can significantly inhibit the release of cytokines in pediatric patients after surgery. One of the mechanisms may be the inhibition of IL-1ß- induced release of IL-6 in the central nervous system.


Assuntos
Hipnóticos e Sedativos/administração & dosagem , Imunidade/efeitos dos fármacos , Midazolam/administração & dosagem , Cuidados Pós-Operatórios , Adolescente , Fatores Etários , Animais , Linhagem Celular , Criança , Pré-Escolar , Citocinas/sangue , Feminino , Humanos , Masculino , Propofol/administração & dosagem , Ratos , Resultado do Tratamento
8.
Genet Mol Res ; 14(1): 2799-808, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25867429

RESUMO

Sucrose phosphate synthase (SPS) is an enzyme used by higher plants for sucrose synthesis. In this study, three primer sets were designed on the basis of known SPS sequences from maize (GenBank: NM_001112224.1) and sugarcane (GenBank: JN584485.1), and five novel SPS genes were identified by RT-PCR from the genomes of Pennisetum spp (the hybrid P. americanum x P. purpureum, P. purpureum Schum., P. purpureum Schum. cv. Red, P. purpureum Schum. cv. Taiwan, and P. purpureum Schum. cv. Mott). The cloned sequences showed 99.9% identity and 80-88% similarity to the SPS sequences of other plants. The SPS gene of hybrid Pennisetum had one nucleotide and four amino acid polymorphisms compared to the other four germplasms, and cluster analysis was performed to assess genetic diversity in this species. Additional characterization of the SPS gene product can potentially allow Pennisetum to be exploited as a biofuel source.


Assuntos
Variação Genética , Glucosiltransferases/genética , Pennisetum/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Análise por Conglomerados , DNA Complementar/química , DNA Complementar/genética , Genoma de Planta/genética , Dados de Sequência Molecular , Pennisetum/classificação , Pennisetum/enzimologia , Filogenia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
9.
Neuroscience ; 290: 570-80, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25665753

RESUMO

Estrogen receptor-related receptor-α (ERRα) is an orphan member of the nuclear receptor superfamily that interacts with peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) to stimulate vascular endothelial growth factor (VEGF) expression and angiogenesis in a hypoxia-inducible factor-1α-independent pathway. Although it is not regulated by any natural ligand, the action of ERRα can be blocked by the synthetic molecule XCT790. In the present study, Sprague-Dawley rats were randomly allocated to a sham group, injury-saline group or injury-XCT90 group. A modified Allen's weight-drop method was applied to induce the acute traumatic spinal cord injury (SCI) model in these rats, and an injection of XCT790 was administered every 24h, starting half an hour after the SCI contusion. Histological analyses revealed that XCT790 significantly aggravated tissue damage and decreased the number of ERRα-positive cells at 1, 3 and 7 days after SCI. Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) analyses also indicated that XCT790 dramatically repressed the expression of ERRα, thus reducing the expression of VEGF and angiopoietin-2 (Ang-2) throughout the duration of the experiment, but the expression of PGC-1α was not affected. Immunofluorescence analyses indicated that vascular density and endothelial cell proliferation were decreased in the injury-XCT90 group compared with the injury-saline group. These results suggest that ERRα is involved in mediating angiogenesis after SCI in the rat traumatic SCI model.


Assuntos
Inibidores da Angiogênese/farmacologia , Neovascularização Patológica/tratamento farmacológico , Nitrilas/farmacologia , Receptores de Estrogênio/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Tiazóis/farmacologia , Angiopoietina-2/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Células Endoteliais/fisiologia , Masculino , Neovascularização Patológica/patologia , Neovascularização Patológica/fisiopatologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Distribuição Aleatória , Ratos Sprague-Dawley , Receptores de Estrogênio/antagonistas & inibidores , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Fatores de Transcrição/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor ERRalfa Relacionado ao Estrogênio
10.
Int Endod J ; 48(1): 95-102, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24646359

RESUMO

AIM: To investigate the effect of chronic periodontitis on dental pulps by assessing histological changes in the pulps of teeth with moderate-to-severe periodontitis. METHODOLOGY: A total of 242 teeth from 162 patients with moderate-to-severe periodontitis were collected, and histological changes in pulps were investigated by staining with haematoxylin and eosin. Baseline data were taken from the patients' records before extraction. The morphologic changes observed in the pulp were classified as degree I, degree II, degree III and degree IV. Statistical analysis of the severity of periodontitis and histological changes with the pulps was applied using the Mann-Whitney U rank sum test, whilst the contingency coefficient was used to analyse the inter-relationship between the severity of periodontitis and histological changes in the pulps. RESULTS: The inter-relationship between the severity of periodontitis and histological changes in the pulps was 0.274 (P < 0.001), and significant differences existed between teeth with moderate periodontitis and severe periodontitis group (Z = 4.145, P < 0.001). The inter-relationship between attachment loss and histological changes in the pulps was 0.397 (P < 0.001). There were significant differences in the histological changes amongst teeth with various degrees of attachment loss (χ(2) = 33.023, P < 0.001) and amongst teeth in different locations (χ(2) = 23.163, P < 0.001). CONCLUSIONS: There was a positive association between the severity of periodontitis and histological changes within the pulp. More attachment loss was correlated with pathological changes within the dental pulp.


Assuntos
Periodontite Crônica/patologia , Polpa Dentária/patologia , Adulto , Idoso , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Coloração e Rotulagem , Extração Dentária
11.
Appl Phys Lett ; 104(16): 163701, 2014 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-24803682

RESUMO

Based on the requirements for studying the dynamic process of proteinase action substrates in life science, we selected six random proteins including 1L-10, SCGB2A2, CENPQ, GST, HK1, KLHL7, as well as five different concentrations of 1L-10 proteins of 1 mg/ml, 0.5 mg/ml, 0.25 mg/ml, 0.125 mg/ml, and 0.0625 mg/ml, and fabricated two types of substrate protein microarrays, respectively. We detected the dynamic processes of proteins degraded by proteinase K using oblique-incidence reflectivity difference (OIRD) method in a label-free and real-time manner. We obtained the relevant degradation velocities and the degradation time. The experimental results demonstrate that OIRD has the ability to study proteinase action substrates which is out of reach of label methods and is expected to offer opportunities to determine protease-substrate relationships on the systems biology level.

12.
Adv Drug Deliv Rev ; 65(4): 515-35, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22727746

RESUMO

After being severely and quasi-plastically deformed, shape memory materials are able to return to their original shape at the presence of the right stimulus. After a brief presentation about the fundamentals, including various shape memory effects, working mechanisms, and typical shape memory materials for biomedical applications, we summarize some major applications in shaping tissue with shape memory materials. The focus is on some most recent development. Outlook is also discussed at the end of this paper.


Assuntos
Materiais Biocompatíveis , Animais , Equipamentos e Provisões , Humanos , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
13.
Osteoarthritis Cartilage ; 19(1): 96-102, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21034837

RESUMO

OBJECTIVE: To measure in vivo thicknesses of the facet joint subchondral bone across genders, age groups, with or without low back pain symptom groups and spinal levels. METHODS: Lumbar (L1-L2 to L5-S1) magnetic resonance (MR) imaging was performed in 81 subjects (41 males and 40 females, mean age 37.6 years). Thicknesses of the subchondral bone were measured in 1620 facet joints using the MR images with custom-written image processing algorithms together with a multi-threshold segmentation technique using each facet joint's middle axial-slice. This method was validated with 12 cadaver facet joints, scanned with both MR and micro-computed tomography images. RESULTS: An overall average thickness value for the 1620 analyzed joints was measured as 1.56±0.01 mm. The subchondral bone thickness values showed significant increases with successive lower spinal levels in the subjects without low back pain. The facet joint subchondral bone thickness in asymptomatic females was much smaller than in asymptomatic males. Mean subchondral bone thickness in the superior facet was greater than that in the inferior facet in both female and male asymptomatic subjects. CONCLUSIONS: This study is the first to quantitatively show subchondral bone thickness using a validated MR-based technique. The subchondral bone thickness was greater in asymptomatic males and increased with each successive lower spinal level. These findings may suggest that the subchondral bone thickness increases with loading. Furthermore, the superior facet subchondral bone was thicker than the inferior facet in all cases regardless of gender, age or spinal level in the subjects without low back pain. More research is needed to link subchondral bone microstructure to facet joint kinematics and spinal loads.


Assuntos
Dor Lombar/patologia , Vértebras Lombares/patologia , Articulação Zigapofisária/patologia , Adulto , Fatores Etários , Análise de Variância , Feminino , Humanos , Região Lombossacral/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteoartrite/patologia , Fatores Sexuais , Adulto Jovem
14.
J Int Med Res ; 38(3): 929-39, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20819429

RESUMO

Ten rabbits implanted with VX2 liver tumours were investigated by perfusion computed tomography (PCT) imaging 1 week (early) and 2 weeks (late) after tumour induction; 10 other rabbits were non-implanted controls. Time-density curves, perfusion parametric maps and perfusion parameters were obtained for tumour rim and normal tissue surrounding the tumour, and for liver tissue from the controls. In addition, microvessel density (MVD) and vascular endothelial growth factor (VEGF) were studied by immunohistochemistry 2 weeks after tumour implantation. A deconvolution mathematical model was used to calculate hepatic blood flow (HBF), hepatic blood volume (HBV), mean transit time (MTT), capillary vessel surface permeability (PS) and hepatic arterial index (HAI). At the tumour rim on the early PCT scan, MTT was significantly lower whereas HBF, HBV, HAI and PS were significantly higher than in surrounding normal tissue. There were no significant changes in perfusion parameters on the late PCT scan compared with the early scan. Significant linear correlations of MVD and VEGF were found with HBF, PS and HAI, but not with HBV or MTT. It is concluded that PCT imaging is useful for the evaluation of tumour angiogenesis and for the early detection of liver tumours.


Assuntos
Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Neovascularização Patológica/patologia , Tomografia Computadorizada por Raios X/métodos , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/diagnóstico por imagem , Modelos Animais de Doenças , Técnicas Imunoenzimáticas , Neoplasias Hepáticas/diagnóstico por imagem , Microvasos/metabolismo , Microvasos/patologia , Transplante de Neoplasias , Neovascularização Patológica/diagnóstico por imagem , Perfusão , Coelhos , Fluxo Sanguíneo Regional , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Br J Sports Med ; 44(2): 114-20, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18523038

RESUMO

BACKGROUND: Animal models for the study of tendinopathy and bone-tendon (B-T) junction repair have been established in the past for sports medicine research. As healing at the B-T junction is difficult and sometimes delayed, establishing a delayed B-T healing experimental model is therefore essential to study the efficacy of potential biophysical and biological interventions for treatment of B-T junction healing. OBJECTIVE: To test the hypothesis that a delay in B-T healing could be modelled by shielding the B-T healing interface for the initial few weeks. METHODS: Using an established partial patellectomy model in rabbits, the B-T healing interface was shielded with a latex slice for the first 4 postoperative weeks in mature female rabbits. The characteristics of delay in B-T repair (n = 10) compared with controls (n = 10) were evaluated at 8 and 12 postoperative weeks. RESULTS: Radiology showed consistent delay in osteogenesis at the healing interface in all samples in the delayed healing group; growth of new bone was only 25.8% and 50.1% of that in the control group at weeks 8 and 12, respectively. Bone mineral density was 56.0% lower in the delayed healing group at week 8, but this difference diminished at week 12. The quality of B-T healing was poor in the delayed healing group, with 22.9% and 24.2% lower failure load than the control group at weeks 8 and 12, respectively. The healing quality was also reflected by histological findings. CONCLUSIONS: A delayed B-T healing experimental model was established for the first time for future sports medicine research.


Assuntos
Traumatismos em Atletas/cirurgia , Regeneração Óssea/fisiologia , Osteogênese/fisiologia , Patela/fisiologia , Ligamento Patelar/fisiologia , Cicatrização/fisiologia , Animais , Traumatismos em Atletas/diagnóstico por imagem , Densidade Óssea , Remodelação Óssea , Feminino , Modelos Animais , Patela/diagnóstico por imagem , Patela/lesões , Ligamento Patelar/diagnóstico por imagem , Ligamento Patelar/lesões , Coelhos , Radiografia , Tendões
16.
Phys Med Biol ; 53(10): 2537-52, 2008 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-18424876

RESUMO

Swelling behavior is an electrochemical mechanical property of articular cartilage. It plays an important role in weight bearing and joint lubrication. In this study, the altered transient and inhomogeneous swelling behavior of the degenerated articular cartilage was observed and quantified in situ using ultrasound. Three groups of bovine patellar articular cartilage samples (n = 10 x 3) were obtained and digested by trypsin for 10, 20 and 30 min respectively to mimic different levels of degeneration. The osmotic-free shrinkage and swelling behavior induced by changing the concentration of the bathing saline solution from 0.15 M to 2 M and then back to 0.15 M were characterized using high-frequency ultrasound (central frequency = 35 MHz) before and after digestion. It was found that the degenerated cartilage specimens showed a weaker shrinkage-swelling behavior compared with the normal cartilage samples. However, no significant differences in the peak shrinkage or swelling strains were observed between different groups. The absolute values of the peak shrinkage strain significantly (p < 0.05) decreased by 45.4%, 42.1% and 50.6% respectively after the trypsin digestion for 10, 20 and 30 min, but such significance was not demonstrated for the peak swelling strains. Due to the potential alterations in the collagen-PG matrix during trypsin digestion, the correlation between the swelling strain and the shrinkage strain of the degenerated samples changed slightly in comparison with the normal samples. The proposed ultrasound method has been successfully used to measure the transient and inhomogeneous swelling behavior of the degenerated articular cartilage and has the potential for the characterization of osteoarthritis.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/metabolismo , Proteoglicanas/deficiência , Animais , Cartilagem Articular/citologia , Bovinos , Pressão Osmótica , Tripsina/metabolismo , Ultrassonografia
17.
Nanotechnology ; 19(4): 045605, 2008 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21817511

RESUMO

A low-cost and catalyst-free two-step approach has been developed to produce ZnO nanotubes (ZNTs) by simple thermal oxidation of Zn nanowires under 20 Pa at a low temperature of 400 °C. The growth mechanism of ZNTs is discussed in detail. The formation of these tubular structures is closely linked to the oxidation pressure and temperature, which involves a process consisting of the deposition of Zn nanowires, cracking of the Zn nanowires and sublimation of the Zn cores, and subsequent oxidation to ZNTs. The optical properties were studied by using Raman and photoluminescence spectra, where a strong green emission related to the single ionized oxygen vacancy appears. The photocatalytic activity measurement indicates an enhanced photocatalytic activity of the prepared ZNTs due to their high surface-to-volume ratios and abundant oxygen vacancies near the surfaces of the ZNTs. This type of high surface area structural ZNTs could find promising potential for optoelectronic and environmental applications.

18.
Nanotechnology ; 19(17): 175501, 2008 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-21825672

RESUMO

We report a kind of gas sensor using ZnO nanowires as the field ionization anode. The sharp tips of nanowires generate very high electric fields at relatively low voltages. The sensors show good sensitivity and selectivity. Moreover, the detection limitation of the field ionization based ZnO nanowire gas sensors is about 5%. More importantly, a sensor with ZnO nanowires as the anode exhibits an impressive performance with respect to stability and anti-oxidation behavior, which are significantly better than those of carbon nanotubes (CNTs) as electrodes. Therefore, the simple, low-cost, sensors described here could be deployed for a variety of applications.

19.
Opt Lett ; 32(17): 2526-8, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17767293

RESUMO

High-sensitivity and visible-blind ultraviolet (UV) photoconductive detectors based on SrTiO(3) single crystal with interdigitated electrodes are reported. The responsivities of photovoltage and photocurrent can reach 2.13x10(5) V/W and 213 mA/W, respectively, at 330 nm at ambient temperature, and the corresponding quantum efficiency eta reaches 80.2%. The dark current is lower than 50 pA at 10 V bias, and the UV/visible contrast ratio is about four orders of magnitude with a sharp cutoff at 390 nm. The experimental results demonstrate that SrTiO(3) single crystal has potentially wide applications in UV detection.

20.
Tissue Eng ; 10(9-10): 1597-606, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15588419

RESUMO

Cranial neural crest-derived ectomesenchymal cells may be pluripotent stem cells that are capable of generating a range of phenotypes. The fate of these cells appears to be determined in part by intrinsic genetic programs and also by the influence of extracellular signals in the local environment. The extent of lineage determination once neural crest cells have migrated to the first branchial arch is not clear, although branchial arch pattern is not thought to be the result of crest predetermination. The aim of the present study was to test the hypothesis that ectomesenchymal cells of the first branchial arch show properties of pluripotent stem cells, the lineage of which may be directed by specific molecular signaling. Ectomesenchymal cells were enzymatically isolated from the mandibular processes of BALB/c mice and maintained in an undifferentiated state while cultured with leukemia inhibitory factor or induced to differentiate by lineage-specific induction factors or growth conditions, including transforming growth factor beta, forskolin, and a mineralization-promoting medium. Morphological observations and immunocytochemistry demonstrated that cells could be induced to differentiate into smooth muscle cells, glial cells, and osteoblasts, respectively. In the presence of the mineralization-promoting medium, alkaline phosphatase activity increased significantly and mineralization nodules formed. The data reported support the concept that many, although not all, first branchial arch-derived ectomesenchymal cells show properties of multipotent stem cells, the subsequent fate of which can be influenced by induction factors and growth conditions. Some cells, however, showed a degree of commitment with respect to their fate. The possible application of first branchial arch-derived stem cells to tissue engineering of the orofacial tissues should involve consideration of the developmental stage of cell harvesting and the desired cell fate.


Assuntos
Região Branquial/citologia , Células-Tronco Mesenquimais/citologia , Músculo Liso/citologia , Crista Neural/citologia , Neuroglia/citologia , Osteoblastos/citologia , Engenharia Tecidual/métodos , Animais , Região Branquial/embriologia , Região Branquial/fisiologia , Diferenciação Celular/fisiologia , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Músculo Liso/fisiologia , Crista Neural/embriologia , Crista Neural/fisiologia , Neuroglia/fisiologia , Osteoblastos/fisiologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/fisiologia
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