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1.
Front Microbiol ; 14: 1226142, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795290

RESUMO

Shihezi Reclamation Area is located at the southern edge of the Junggar Basin, with natural, soil, and climatic conditions unique to the production of peaches. In turn, peach orchards have accumulated rich microbial resources. As an important taxon of soil fungi, the diversity and community structure changes of yeast in the soil of peach orchards on spatial and temporal scales are still unknown. Here, we aimed to investigate the changes in yeast diversity and community structure in non-rhizosphere and rhizosphere soils of peach trees of different ages in the peach orchard and the factors affecting them, as well as the changes in the yeast co-occurrence network in the peach orchard at spatial and temporal scales. High-through put sequencing results showed that a total of 114 yeast genera were detected in all soil samples, belonging to Ascomycota (60 genera) and Basidiomycota (54 genera). The most dominant genus, Cryptococcus, was present in greater than 10% abundance in each sample. Overall, the differences in yeast diversity between non-rhizosphere and rhizosphere soil of peach trees at 3, 8 and 15 years were not significant. Principal coordinate analysis (PCoA) showed that differences in yeast community structure were more pronounced at the temporal scale compared to the spatial scale. The results of soil physical and chemical analysis showed that the 15-year-old peach rhizosphere soil had the lowest pH, while the OM, TN, and TP contents increased significantly. Redundancy analysis showed that soil pH and CO were key factors contributing to changes in soil yeast community structure in the peach orchard at both spatial and temporal scales. The results of co-occurrence network analysis showed that the peach orchard soil yeast network showed synergistic effects as a whole, and the degree of interactions and connection tightness of the 15-year-old peach orchard soil yeast network were significantly higher than the 3- and 8-year-old ones on the time scale. The results reveal the distribution pattern and mechanism of action of yeast communities in peach orchard soils, which can help to develop effective soil management strategies and improve the stability of soil microecology, thus promoting crop growth.

2.
Acta Biomater ; 151: 45-69, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35970479

RESUMO

Three-dimensional (3D) bioprinting is an advanced technology to fabricate artificial 3D tissue constructs containing cells and hydrogels for tissue engineering and regenerative medicine. Nanocomposite reinforcement endows hydrogels with superior properties and tailored functionalities. A broad range of nanomaterials, including silicon-based, ceramic-based, cellulose-based, metal-based, and carbon-based nanomaterials, have been incorporated into hydrogel networks with encapsulated cells for improved performances. This review emphasizes the recent developments of cell-laden nanocomposite bioinks for 3D bioprinting, focusing on their reinforcement effects and mechanisms, including viscosity, shear-thinning property, printability, mechanical properties, structural integrity, and biocompatibility. The cell-material interactions are discussed to elaborate on the underlying mechanisms between the cells and the nanomaterials. The biomedical applications of cell-laden nanocomposite bioinks are summarized with a focus on bone and cartilage tissue engineering. Finally, the limitations and challenges of current cell-laden nanocomposite bioinks are identified. The prospects are concluded in designing multi-component bioinks with multi-functionality for various biomedical applications. STATEMENT OF SIGNIFICANCE: 3D bioprinting, an emerging technology of additive manufacturing, has been one of the most innovative tools for tissue engineering and regenerative medicine. Recent developments of cell-laden nanocomposite bioinks for 3D bioprinting, and cell-materials interactions are the subject of this review paper. The reinforcement effects and mechanisms of nanocomposites on viscosity, printability and biocompatibility of bioinks and 3D printed scaffolds are addressed mainly for bone and cartilage tissue engineering. It provides detailed information for further designing and optimizing multi-component bioinks with multi-functionality for specialized biomedical applications.


Assuntos
Bioimpressão , Nanocompostos , Bioimpressão/métodos , Carbono , Celulose , Hidrogéis/química , Impressão Tridimensional , Silício , Engenharia Tecidual , Alicerces Teciduais/química
3.
J Clin Lab Anal ; 36(4): e24347, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35302673

RESUMO

BACKGROUND: CircRNA is a very important functional RNA that plays an important role in the development and metabolism of cancer. However, the study of circRNA in NSCLC has not been fully elucidated. METHODS: The expression of hsa_circ_0017620, SFMBT2, miR-520a-5p, and KRT5 was determined using qRT-PCR. KRT5, Twist1, E-cadherin, and Ki67 protein expression were measured with western blot. The positive expression rates of Ki67 and Vimentin were determined by immunohistochemistry assay. 5-Ethynyl-2'-deoxyuridine (EdU), colony formation, and MTT assays were used to assess cell proliferation. Transwell migration and invasion assay were applied to determine cell migration and invasion. Dual-luciferase reporter and RNA immunoprecipitation assays were used to verify the relationship among hsa_circ_0017620, miR-520a-5p, and KRT5. The animal experiment was used to ensure the effects of hsa_circ_0017620 on tumor growth in vivo. RESULTS: Hsa_circ_0017620 was upregulated in NSCLC cells and tissues. MiR-520a-5p had been verified to be a target miRNA of hsa_circ_0017620 and KRT5 had been verified to be a target mRNA of miR-520a-5p in NSCLC cells. Knockdown of hsa_circ_0017620 inhibited cell proliferation, migration, and invasion in NSCLC cells, which was reversed by downregulating miR-520a-5p or upregulating KRT5 in NSCLC. Overexpression of hsa_circ_0017620 had opposite effects in NSCLC. Moreover, hsa_circ_0017620 silencing inhibited tumor growth in vivo of NSCLC. CONCLUSION: In this study, we found that hsa_circ_0017620 played an important role in NSCLC progression. Hsa_circ_0017620 regulated cell proliferation, invasion, and migration through targeting miR-520a-5p/KRT5 axis in NSCLC, providing a potential new target for the treatment and diagnosis of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/genética , Humanos , Queratina-5 , Antígeno Ki-67 , Neoplasias Pulmonares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética
4.
Thorac Cancer ; 12(23): 3223-3235, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34658165

RESUMO

BACKGROUND: Currently, the prognosis of non-small-cell lung cancer (NSCLC) patients remains dismal due to recurrence and metastasis. The purpose of our study was to explore the role of circular RNA_0016760 (circ_0016760) in NSCLC progression and its associated mechanism. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was implemented to measure the expression of circ_0016760, microRNA-646 (miR-646) and AK strain thymoma serine/threonine kinase 3 (AKT3). The protein level of AKT3 was examined by Western blot assay. Cell Counting Kit 8 assay, transwell assays, and flow cytometry were conducted to analyze cell proliferation, metastasis, and apoptosis. Dual-luciferase reporter assay was used to confirm the interactions that were predicted by bioinformatics software (Circular RNA Interactome and TargetScan). A xenograft tumor model was built to investigate the role of circ_0016760 in vivo. RESULTS: Circ_0016760 and AKT3 were highly expressed in NSCLC tissue specimens and cell lines. Circ_0016760 interference suppressed cell proliferation, migration, and invasion and promoted the apoptosis of NSCLC cells. Circ_0016760 interacted with miR-646 and negatively regulated its expression. MiR-646 silencing partly counteracted circ_0016760 knockdown-mediated influences in NSCLC cells. MiR-646 bound to the AKT3 3' untranslated region in NSCLC cells, and miR-646 overexpression-induced effects in NSCLC cells were partly overturned by the addition of AKT3 overexpression plasmid. Circ_0016760 silencing reduced the expression of AKT3 through enhancing miR-646 expression. Circ_0016760 knockdown suppressed NSCLC tumor growth in vivo. CONCLUSION: Circ_0016760 played an oncogenic role to promote the proliferation, migration, and invasion and restrained the apoptosis of NSCLC cells via miR-646/AKT3 signaling.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA Circular/genética , Células A549 , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Invasividade Neoplásica/genética , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Medicine (Baltimore) ; 100(16): e25589, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33879719

RESUMO

RATIONALE: Reversible posterior leukoencephalopathy syndrome (RPLS) is a clinicoradiological phenomenon first observed 2 decades ago. Reversibility is the hallmark of this rare clinical phenomenon once the triggering pathology is aptly and adequately treated. Tinnitus preceding bilateral hearing loss as a symptomatology of RPLS has not been reported in the literature. Furthermore, chronic obstructive ureteric calculus with superimposed infections as a cause of RPLS has not been reported in the literature. PATIENT CONCERNS: A 57-year-old female was admitted at our facility because of 2 days history of hearing loss in both ears. She experienced tinnitus in both ears 2 weeks prior to the hearing loss. She is a known hypertensive. She has also undergone multiple surgical treatments for urinary calculi. DIAGNOSIS: Computed tomography (CT) scan of the urinary system revealed a calculus at the right ureter. Magnetic resonance imaging (MRI) showed abnormal signals at both temporo-parieto-occipital (TPO) cortices, the subcortical area, as well as the left hippocampus which was consistent with the diagnosis of RPLS. INTERVENTIONS: While on antibiotics for treatment of infections, the patient went into hypertensive encephalopathy and pneumonia was also established necessitating intensive care. OUTCOMES: We observed a resolution of the patient's temperature and hypertension when the right ureteric stone finally descended into the bladder. Also, we observed disappearance of the abnormal signals at both TPO cortices, the subcortical area, as well as the left hippocampus. Two years follow-up revealed no recurrence of her symptomatology. LESIONS: Patients who present with hypertensive encephalopathy maybe more prone to developing RPLS. Renal insufficiency alone or hypertension alone may not be single predisposing entities to RPLS but rather multiple predisposing factors.


Assuntos
Perda Auditiva Bilateral/diagnóstico por imagem , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Zumbido/diagnóstico por imagem , Cálculos Urinários/complicações , Infecções Urinárias/complicações , Encéfalo/diagnóstico por imagem , Feminino , Perda Auditiva Bilateral/etiologia , Humanos , Hipertensão/etiologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Síndrome da Leucoencefalopatia Posterior/etiologia , Zumbido/etiologia , Tomografia Computadorizada por Raios X , Ureter/diagnóstico por imagem , Cálculos Urinários/diagnóstico por imagem , Infecções Urinárias/diagnóstico por imagem
6.
Eur Neurol ; 84(2): 96-102, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33684912

RESUMO

BACKGROUND: Cerebral infarction associated with atrial fibrillation (AF) has relatively higher mortality and morbidity rates than other types of stroke. Statins are being commonly prescribed to patients with stoke. However, the use of statins in AF-related stroke, especially prestroke, has not been well studied. This study aimed to investigate whether the use of prestroke statins could improve clinical outcomes in patients with AF-related acute ischemic stroke (AIS) and its mechanism. METHODS: This prospective study enrolled 453 AF-associated AIS patients from 4 medical centers and divided them into 2 groups based on the statin use before the stroke episode. All patients received comprehensive clinical examinations including 72-h Holter electrocardiogram monitoring and were followed up for 3 months. Plasma suppressor of cytokine signaling-3 (SOCS-3) and matrix metalloproteinase-9 (MMP-9) levels were measured by ELISA on admission and days 3 and 7 after enrollment. The endpoints were death, major disability (modified Rankin Scale score ≥3), and composite outcome (death/major disability) at 3 months after the AIS episode. RESULTS: Plasma SOCS-3 levels were significantly increased and MMP-9 levels decreased in patients in the prestroke statin group on hospital admission and days 3 and 7 after enrollment (p < 0.001). Furthermore, our data suggested that baseline plasma SOCS-3 levels were associated with increased risk of 3-month mortality (adjusted odds ratio [OR], 1.012; 95% confidence interval [CI], 1.006-1.018; p < 0.001) and major disability (adjusted OR, 1.013; 95% CI, 1.007-1.02; p < 0.001). Similarly, baseline plasma MMP-9 levels were also associated with increased risk of 3-month mortality (adjusted OR, 1.037; 95% CI, 1.022-1.053; p < 0.001) and major disability (adjusted OR, 1.038; 95% CI, 1.022-1.55; p < 0.001). CONCLUSION: Our data suggested that the prestroke use of statins improved the clinical outcomes in AIS patients with AF by upregulating the level of SOCS-3 and reducing the plasma MMP-9 level.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , Inibidores de Hidroximetilglutaril-CoA Redutases , Acidente Vascular Cerebral , Proteína 3 Supressora da Sinalização de Citocinas , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Citocinas , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Prognóstico , Estudos Prospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Proteína 3 Supressora da Sinalização de Citocinas/genética
7.
Curr Med Imaging ; 17(8): 1031-1035, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33480347

RESUMO

INTRODUCTION: Endovascular therapy (EVT) for intracranial arterial aneurysms is depicted with several complications. Very recently, delayed non-ischemic cerebral enhanced (NICE) lesions have been identified as a rare complication associated with EVT. This complication always stands a higher chance of being missed in asymptomatic patients. We report a case of multiple NICE lesions in a known chronic hepatitis B infection and chronic gastritis patient with left internal carotid aneurysm (ICA) treated with detachable coils. CASE PRESENTATION: A 52 years old female with left ICA was treated with detachable coils via the endovascular route. Three weeks after the operation, she presented with numbness of her right limbs which was persistent and waked her up from sleep each night. She admitted skin allergies after wearing metals except for gold and silver since childhood. MRI revealed multiple abnormal lesions in the left temporal lobe, hippocampus, insula, and parietal lobe and some perifocal edema which were consistent with the diagnosis of delayed NICE lesions. CONCLUSION: It is very important to report the occurrences of these lesions in literature because of their allergic origin. We advocate that allergy to metals especially those used in coating endovascular equipment should be evaluated before every EVT for intracranial aneurysms.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Criança , Procedimentos Endovasculares/efeitos adversos , Feminino , Hipocampo , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
8.
Sci Rep ; 6: 25510, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-27138687

RESUMO

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (PST), is one of the most destructive diseases and can cause severe yield losses in many regions of the world. Because of the large size and complexity of wheat genome, it is difficult to study the molecular mechanism of interaction between wheat and PST. Brachypodium distachyon has become a model system for temperate grasses' functional genomics research. The phenotypic evaluation showed that the response of Brachypodium distachyon to PST was nonhost resistance (NHR), which allowed us to present this plant-pathogen system as a model to explore the immune response and the molecular mechanism underlying wheat and PST. Here we reported the generation of about 7,000 T-DNA insertion lines based on a highly efficient Agrobacterium-mediated transformation system. Hundreds of mutants either more susceptible or more resistant to PST than that of the wild type Bd21 were obtained. The three putative target genes, Bradi5g17540, BdMYB102 and Bradi5g11590, of three T-DNA insertion mutants could be involved in NHR of Brachypodium distachyon to wheat stripe rust. The systemic pathologic study of this T-DNA mutants would broaden our knowledge of NHR, and assist in breeding wheat cultivars with durable resistance.


Assuntos
Brachypodium/genética , DNA Bacteriano/genética , Interações Hospedeiro-Patógeno/genética , Triticum/genética , Agrobacterium tumefaciens/genética , Basidiomycota/genética , Basidiomycota/patogenicidade , Brachypodium/microbiologia , Cruzamento , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Triticum/microbiologia
9.
Colloids Surf B Biointerfaces ; 116: 681-6, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24304498

RESUMO

Titanium alloys have been widely used in orthopedic practice due to their inherent bioactivity, however it is still insufficient to truly and reliably incorporate into living bone. In this work, polydopamine film was employed to induce the growth of hydroxyapatite (HA) on titanium alloy to enhance its osteoconductivity. Bone morphogenetic protein-2 (BMP2) peptide was absorbed into the HA particles for osteoinductivity. The precipitation of HA and the existence of BMP2 peptide were examined by X-ray diffraction, X-ray photoelectron spectroscopy and fluorescence microscopy. The dissolution of HA and the release of BMP2 peptide were monitored by measuring the concentrations of calcium ions and BMP2 peptide in phosphate buffered saline solution, respectively. The effect of BMP2 peptide incorporated into HA coating on bone growth was evaluated in vitro by cell culture tests, including cell attachment, alkaline phosphatase (ALP) activity, and gene expression. The results show that the HA particles grown on the substrate are mediated by the polydopamine film. The BMP2 peptide is distributed uniformly on HA-coated substrate and released in a sustained manner. Moreover, the conjunction of HA and BMP2 peptide increases cell adhesion, ALP activity and gene expression of osteogenic markers, which are potentially useful in the development of enhanced orthopedic medical devices.


Assuntos
Ligas/farmacologia , Desenvolvimento Ósseo/efeitos dos fármacos , Proteína Morfogenética Óssea 2/química , Durapatita/farmacologia , Titânio/farmacologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Ligas/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Durapatita/química , Humanos , Propriedades de Superfície , Titânio/química
10.
ACS Appl Mater Interfaces ; 5(16): 8179-86, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23927373

RESUMO

Surface microstructure and chemical composition of the implant are very important for its osseointegration in vivo. In this paper, a hierarchical micropattern covered with calcium phosphate (Ca/P phase) was obtained on titanium (Ti) implant surface by femtosecond lasers (FSL) irradiation in hydroxyapatite suspension. The hierachical micropattern as well as Ca/P phase increased osteoblastic cell adhesion. Higher expression of osteogenic markers (osteocalcin, osteopontin, and runt related transcription factor-2) on the surface treated by FSL of 2.55 J/cm(2) indicated the favorable effect of laser treatment on cell differentiation. In vivo studies were carried out to evaluate the effect of laser treatment and Ca/P deposition on the osseointegration. It showed that the binding capacity between bone and FSL-treated Ti implants was obviously stronger than that between bone and polished or sand blasting and acid etching (SLA) Ti implants. Bone trabecula surrounded the FSL-treated implants without fibrous tissue after 8-week implantation. Also, higher bone mineral density was seen surrounding the FSL-treated implants. Our in vitro and in vivo studies demonstrated that the FSL induced micropattern and Ca/P phase had positive effects on the acceleration of early osseointegration of Ti implants with bone tissue.


Assuntos
Materiais Revestidos Biocompatíveis , Osseointegração , Próteses e Implantes , Titânio/química , Densidade Óssea , Osso e Ossos/lesões , Fosfatos de Cálcio/química , Durapatita/química , Lasers , Propriedades de Superfície/efeitos da radiação
11.
Artigo em Inglês | MEDLINE | ID: mdl-23970940

RESUMO

The activated nuclear factor-KappaB signaling pathway plays a critical role in inducing inflammatory injury. It has been reported that electroacupuncture could be an effective anti-inflammatory treatment. We aimed to explore the complex mechanism by which EA inhibits the activation of the NF- κ B signal pathway and ameliorate inflammatory injury in the short term; the effects of NEMO Binding Domain peptide for this purpose were compared. Focal cerebral I/R was induced by middle cerebral artery occlusion for 2 hrs. Total 380 male Sprague-Dawley rats are in the study. The neurobehavioral scores, infarction volumes, and the levels of IL-1 ß and IL-13 were detected. NF- κ B p65, I κ B α , IKK α , and IKK ß were analyzed and the ability of NF- κ B binding DNA was investigated. The EA treatment and the NBD peptide treatment both reduced infarct size, improved neurological scores, and regulated the levels of IL-1 ß and IL-13. The treatment reduced the expression of IKK α and IKK ß and altered the expression of NF- κ B p65 and I κ B α in the cytoplasm and nucleus; the activity of NF- κ B was effectively reduced. We conclude that EA treatment might interfere with the process of NF- κ B nuclear translocation. And it also could suppress the activity of NF- κ B signaling pathway to ameliorate the inflammatory injury after focal cerebral ischemia/reperfusion.

12.
J Orthop Res ; 31(6): 983-90, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23456668

RESUMO

Orthopedic metallic prosthetic implants are commonly made of cobalt chromium (CoCr) alloys. However, such metal-based implants are susceptible to fibrous capsule formation on the implant surface after implantation. At the bone-implant interface, this capsule can prevent implant integration, resulting in loosening and failure. Minimizing the development of such a capsule on the CoCr surface would improve direct bone-implant bonding leading to long-term implant functionality. We evaluated the anti-fibrosis effect of bone morphogenic protein-7 (BMP-7) peptide covalently bonded to CoCr alloy. This peptide, a biomimetic derivation of the knuckle epitope of BMP-7, was conjugated at the N-terminus with a cysteine amino acid. X-ray photoelectron spectroscopy (XPS) and probe binding assay were used to evaluate different stages of grafting and surface functionalization using polydopamine coating. Cellular functions were studied using fibroblast attachment, cell proliferation, and MTT assays. Fibroblasts were grown on functionalized and pristine CoCr substrates, and the efficacy of BMP-7 peptide on anti-fibrosis was analyzed via gene expression and protein expression of fibrosis markers ACTA2, Collagen 1A1, and fibronectin. The peptide functionalized substrates showed significant reduction of fibrosis markers expression after 1 week of incubation compared to controls. BMP-7 signaling pathway activation was shown by the presence of phosphorylation of Smad1/5/8. These findings may contribute to the improvement of CoCr implants in orthopedic surgery applications.


Assuntos
Proteína Morfogenética Óssea 7/fisiologia , Ligas de Cromo/química , Fibroblastos/fisiologia , Fibrose/fisiopatologia , Actinas/metabolismo , Animais , Biomarcadores/metabolismo , Proteína Morfogenética Óssea 7/química , Adesão Celular , Técnicas de Cultura de Células , Proliferação de Células , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Fibronectinas/metabolismo , Camundongos , Células NIH 3T3 , Reação em Cadeia da Polimerase em Tempo Real , Propriedades de Superfície
13.
J Mater Chem B ; 1(43): 5971-5976, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-32261064

RESUMO

Current surgical and repair treatments for articular cartilage defects still do not give satisfactory long-term results. Scaffold-based tissue engineering is the subject of much intensive interest. However, one major hurdle is that it is unable to accurately replicate the internal three dimensional (3D) microstructure of cartilage. In this work, a novel electrohydrodynamic printing (E-Jetting) technique was employed to fabricate 3D polycaprolactone (PCL) scaffolds, followed by collagen grafting mediated by polydopamine. Surface topography, chemical composition, and wettability of the scaffolds before and after surface functionalization were characterized. Porcine chondrocytes were seeded within the scaffolds for chondrogenesis evaluation. The results showed that a 3D PCL scaffold with controlled fibre diameter, orientation, and pore size was fabricated by the E-Jetting system. The surface functionalization made the PCL scaffold hydrophilic and favourable for cell attachment. The chondrocytes maintained their healthy phenotypes within the collagen grafted PCL scaffold. The increased production of sulfated glycosaminoglycan and highly expressed collagen type II demonstrated that collagen had a positive role in stimulating chondrogenesis and the collagen grafted PCL scaffold was effective in cartilage regeneration.

14.
Biotechnol Bioeng ; 110(3): 969-79, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23055400

RESUMO

Cobalt chromium (CoCr) alloy is widely used in orthopedic implants but its functional longevity is susceptible to inflammation related complications. Reduction of the development of chronic inflammation on the biomaterial surface would enhance direct bone-implant bonding and improve implant survival and long-term results. The BMP-7 peptide was derived from the knuckle epitope of bone morphogenic protein-7 (BMP-7) and was conjugated via a cysteine amino acid at the N-terminus. Mouse RAW 264.7 monocytes/macrophages were seeded on the CoCr substrates and inflammation was induced via lipopolysaccharide (LPS) challenge. The effects of BMP-7 peptide on inflammation were evaluated by measuring the expression of inflammatory markers like toll-like receptor-4 (TLR-4), tumor necrosis factor-α (TNF-α), and monocyte chemotactic protein-1 (MCP-1). ELISA and qPCR assays were used to study the inflammatory signals. BMP-7 signaling pathway activation was shown by the presence of phosphorylation of Smad1/5/8. Utilizing the reactivity of polydopamine films to immobilize BMP-7 peptide onto metal substrates may provide a promising approach for applications in situations where reduction of inflammation around implants would be beneficial in improving surgical outcome, bone healing, and implant integration.


Assuntos
Ligas/toxicidade , Proteína Morfogenética Óssea 7/metabolismo , Cromo/toxicidade , Cobalto/toxicidade , Fatores Imunológicos/metabolismo , Macrófagos/imunologia , Monócitos/imunologia , Ligas/química , Animais , Proteína Morfogenética Óssea 7/química , Linhagem Celular , Quimiocina CCL2/metabolismo , Cromo/química , Cobalto/química , Ensaio de Imunoadsorção Enzimática , Fatores Imunológicos/química , Macrófagos/efeitos dos fármacos , Camundongos , Monócitos/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
15.
Artigo em Chinês | MEDLINE | ID: mdl-23072139

RESUMO

OBJECTIVE: To perform molecular cloning of the AGO2 and Dcr-2 gene fragments associated with RNA interference pathway of Aedes albopictus and characterize the transcription level of the two genes across all life stages of the mosquito. METHODS: The degenerate primers were designed based on the conserved regions of AGO2 and Dcr-2 amino acid sequences, and the AGO2 and Dcr-2 cDNA fragments were amplified from total RNA of a female mosquito by RT-PCR. The PCR products were cloned into pMD18-T vector and transformed into E. coli DH5alpha strain, and the positive clones were selected and sequenced, with the results for homology analysis by Blastx. The specific primers were designed according to the sequences of AGO2 and Dcr-2 from Ae. albopictus, which were used to investigate the transcription levels of these two genes from eggs, I and II instars larvae, III and IV instars larvae, pupa, male and female mosquitoes by semi-quantitative RT-PCR. RESULTS: The AGO2 and Dcr-2 cDNA fragments obtained were 326 bp and 491 bp in length, with the Accession number of JQ764670 and JQ764671, respectively. The Blastx analysis showed that the AGO2 and Dcr-2 amino acid sequences shared 91% similarity to AGO2 of Ae. aegypti and 98% to Dcr-2 of Ae. albopictus. The transcription of AGO2 and Dcr-2 genes was detected in all life stages of Ae. albopictus, with the highest level of mRNA in female mosquitoes, which was 3.1 times and 15.5 times higher for AGO2 and Dcr-2 than in male mosquitoes, respectively, and significantly higher than other developmental stages (P<0.05). CONCLUSION: The AGO2 and Dcr-2 cDNA sequences have been partially obtained and the highest transcription level found in female Ae. albopictus, suggesting that AGO2 and Dcr-2 are the key genes of RNA interference in female mosquitoes.


Assuntos
Aedes/crescimento & desenvolvimento , Aedes/genética , Genes de Insetos , Proteínas de Insetos/metabolismo , Animais , Clonagem Molecular , Primers do DNA , DNA Complementar , Feminino , Proteínas de Insetos/genética , Larva/genética , Masculino , Interferência de RNA , Transcrição Gênica
16.
Zhen Ci Yan Jiu ; 37(3): 179-85, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22934386

RESUMO

OBJECTIVE: To observe the influence of electroacupuncture (EA) of "Hegu" (LI 4) on blood stromal cell-derived factor 1alpha (SDF-1alpha), CXC chemokine receptor 4+ (CXCR 4+) positive cells and endothelial progenitor cells (EPCs) and bone marrow (BM) EPCs levels in local cerebral ischemia/reperfusion injury (CI/IR) rats, so as to study its mechanisms underlying improvement of cerebral ischemia. METHODS: A total of 54 SD rats were randomly divided into normal control, model, and EA groups. The latter two groups were further divided into 1 d, 2 d, 3 d and 7 d subgroups (4 time-points), respectively. CI/RI model was established by occlusion of the middle cerebral artery. EA (40 Hz/60 Hz, 1-2 mA) was applied to bilateral "Hegu" (LI 4) for 15 min, once daily, 1, 2, 3 and 7 days, respectively. Flow cytometer was used to detect the counts of EPCs and CXCR 4+ cells in the peripheral blood, and BM EPCs. Serum SDF-1alpha was detected by enzyme linked immunosorbent assay (ELISA). RESULTS: Compared with the normal control group, the percentages of blood EPCs and CXCR 4+ cells and BM EPCs, and serum SDF-1alpha content on the 1st day, and the percentage of blood CXCR 4+ cells on the 2nd day were increased significantly in the model group (P<0.01, P<0.05). In comparison with the model group, percentages of blood EPCs and CXCR 4+ cells on the 1st day of EA group were reduced significantly (P<0.01), but the percentage of blood EPCs on the 2nd day, those of blood CXCR 4+ cells on the 2nd day and 3rd day, serum SDF-1alpha content on the 2nd day, and the percentage of BM EPCs on the 2nd day in the EA group were all up-regulated significantly (P<0.05, P<0.01). No significant differences were found among the 3 groups in blood EPCs percentages on the 3rd day and 7th day, in blood SDF-1alpha content and BM EPCs percentage on the 7th day (P>0.05). CONCLUSION: Generally, 2 days' EA of LI 4 can up-regulate the percentages of blood and BM EPCs and blood CXCR 4+ cells as well as blood SDF-1alpha protein content in CI/RI rats, which may contribute to its effect in improving cerebral ischemia.


Assuntos
Células da Medula Óssea/patologia , Isquemia Encefálica/complicações , Eletroacupuntura , Células Endoteliais/patologia , Leucócitos Mononucleares/patologia , Traumatismo por Reperfusão/terapia , Células-Tronco/metabolismo , Animais , Contagem de Células , Quimiocina CXCL12/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Receptores CXCR4/metabolismo , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/metabolismo , Células-Tronco/patologia
17.
J Mater Sci Mater Med ; 22(7): 1633-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21614594

RESUMO

Dissolution resistance and adhesion strength are two main concerns for long-term stability of surface coated metal implants. In this study, fluorine ions are incorporated into magnesium-containing hydroxyapatite coatings (MgF(y)HA) via sol-gel method to improve the long-term stability of the implants. Surface and interface are studied in terms of phases, depth profiling and chemical bonds by grazing incidence X-ray diffraction, glow discharge optical emission spectroscopy and X-ray photoelectron spectroscopy. The long-term stability is evaluated by dissolution and pull-off test. The results show that fluorine promotes the incorporation of magnesium in HA lattice. The elemental interdiffusion and chemical bonding take place at the coating/substrate interface. Both the dissolution resistance and the adhesion strength are enhanced by fluorine incorporation, thus the long-term stability of the implant is improved.


Assuntos
Materiais Biocompatíveis/química , Durapatita/química , Flúor/química , Magnésio/química , Teste de Materiais , Espectroscopia Fotoeletrônica , Análise Espectral/métodos , Propriedades de Superfície , Difração de Raios X
18.
Langmuir ; 26(23): 18424-9, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21049918

RESUMO

In the past decade, the pore diameter of anodic titania nanotubes was reported to be influenced by a number of factors in organic electrolyte, for example, applied potential, working distance, water content, and temperature. All these were closely related to potential drop in the organic electrolyte. In this work, the essential role of electric field originating from the potential drop was directly revealed for the first time using a simple two-electrode anodizing method. Anodic titania nanotube arrays were grown simultaneously at both sides of a titanium foil, with tube length being longer at the front side than that at the back side. This lopsided growth was attributed to the higher ionic flux induced by electric field at the front side. Accordingly, the nanotube length was further tailored to be comparable at both sides by modulating the electric field. These results are promising to be used in parallel configuration dye-sensitized solar cells, water splitting, and gas sensors, as a result of high surface area produced by the double-sided architecture.


Assuntos
Nanotecnologia/métodos , Nanotubos/química , Titânio/química , Eletroquímica/métodos , Eletrodos , Íons , Teste de Materiais , Microscopia Eletrônica de Varredura/métodos , Modelos Químicos , Prótons
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