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1.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34298988

RESUMO

This study evaluated the biocompatibility and biological performance of novel additive-manufactured bioabsorbable iron-based porous suture anchors (iron_SAs). Two types of bioabsorbable iron_SAs, with double- and triple-helical structures (iron_SA_2_helix and iron_SA_3_helix, respectively), were compared with the synthetic polymer-based bioabsorbable suture anchor (polymer_SAs). An in vitro mechanical test, MTT assay, and scanning electron microscope (SEM) analysis were performed. An in vivo animal study was also performed. The three types of suture anchors were randomly implanted in the outer cortex of the lateral femoral condyle. The ultimate in vitro pullout strength of the iron_SA_3_helix group was significantly higher than the iron_SA_2_helix and polymer_SA groups. The MTT assay findings demonstrated no significant cytotoxicity, and the SEM analysis showed cells attachment on implant surface. The ultimate failure load of the iron_SA_3_helix group was significantly higher than that of the polymer_SA group. The micro-CT analysis indicated the iron_SA_3_helix group showed a higher bone volume fraction (BV/TV) after surgery. Moreover, both iron SAs underwent degradation with time. Iron_SAs with triple-helical threads and a porous structure demonstrated better mechanical strength and high biocompatibility after short-term implantation. The combined advantages of the mechanical superiority of the iron metal and the possibility of absorption after implantation make the iron_SA a suitable candidate for further development.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis , Âncoras de Sutura , Alanina Transaminase/sangue , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Fenômenos Biomecânicos , Nitrogênio da Ureia Sanguínea , Fosfatos de Cálcio/química , Fosfatos de Cálcio/toxicidade , Sulfato de Cálcio/administração & dosagem , Sulfato de Cálcio/química , Sulfato de Cálcio/toxicidade , Creatinina/sangue , Desenho de Equipamento , Fêmur/diagnóstico por imagem , Fêmur/ultraestrutura , Ferro , Lasers , Teste de Materiais , Microscopia Eletrônica de Varredura , Estrutura Molecular , Osseointegração , Polímeros/química , Polímeros/toxicidade , Porosidade , Coelhos , Distribuição Aleatória , Resistência à Tração , Vísceras , Microtomografia por Raio-X
2.
Int J Mol Sci ; 21(17)2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878186

RESUMO

The acceleration of peripheral nerve regeneration is crucial for functional nerve recovery. Our previous study demonstrated that human Wharton's jelly-derived mesenchymal stem cells (hWJ-MSC) promote sciatic nerve recovery and regeneration via the direct upregulation and release of neurotrophic factors. However, the immunomodulatory role of hWJ-MSC in sciatic nerve recovery remains unclear. The effects of hWJ-MSC on innate immunity, represented by macrophages, natural killer cells, and dendritic cells, as well as on adaptive immunity, represented by CD4+ T, CD8+ T, B, and regulatory T cells (Tregs), were examined using flow cytometry. Interestingly, a significantly increased level of Tregs was detected in blood, lymph nodes (LNs), and nerve-infiltrating cells on POD7, 15, 21, and 35. Anti-inflammatory cytokines, such as IL-4 and IL-10, were significantly upregulated in the LNs and nerves of hWJ-MSC-treated mice. Treg depletion neutralized the improved effects of hWJ-MSC on sciatic nerve recovery. In contrast, Treg administration promoted the functional recovery of five-toe spread and gait stance. hWJ-MSC also expressed high levels of the anti-inflammatory cytokines TGF-ß and IL-35. This study indicated that hWJ-MSC induce Treg development to modulate the balance between pro- and anti-inflammation at the injured sciatic nerve by secreting higher levels of anti-inflammatory cytokines.


Assuntos
Citocinas/metabolismo , Células-Tronco Mesenquimais/citologia , Nervo Isquiático/citologia , Linfócitos T Reguladores/imunologia , Geleia de Wharton/citologia , Animais , Proliferação de Células , Células Cultivadas , Fatores Imunológicos/metabolismo , Células-Tronco Mesenquimais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Nervo Isquiático/imunologia , Geleia de Wharton/imunologia
3.
Int J Mol Sci ; 21(10)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455543

RESUMO

The interference screw fixation method is used to secure a graft in the tibial tunnel during anterior cruciate ligament reconstruction surgery. However, several complications have been reported, such as biodegradable screw breakage, inflammatory or foreign body reaction, tunnel enlargement, and delayed graft healing. Using additive manufacturing (AM) technology, we developed a titanium alloy (Ti6Al4V) interference screw with chemically calcium phosphate surface modification technology to improve bone integration in the tibial tunnel. After chemical and heat treatment, the titanium screw formed a dense apatite layer on the metal surface in simulated body fluid. Twenty-seven New Zealand white rabbits were randomly divided into control and additive manufactured (AMD) screw groups. The long digital extensor tendon was detached and translated into a tibial plateau tunnel (diameter: 2.0 mm) and transfixed with an interference screw while the paw was in dorsiflexion. Biomechanical analyses, histological analyses, and an imaging study were performed at 1, 3, and 6 months. The biomechanical test showed that the ultimate pull-out load failure was significantly higher in the AMD screw group in all tested periods. Micro-computed tomography analyses revealed early woven bone formation in the AMD screw group at 1 and 3 months. In conclusion, AMD screws with bioactive surface modification improved bone ingrowth and enhanced biomechanical performance in a rabbit model.


Assuntos
Parafusos Ósseos/normas , Osseointegração , Impressão Tridimensional , Tendões/cirurgia , Tíbia/cirurgia , Ligas/química , Animais , Parafusos Ósseos/efeitos adversos , Interface Osso-Implante/cirurgia , Fosfatos de Cálcio/química , Porosidade , Coelhos
4.
Int Immunopharmacol ; 79: 106106, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31874369

RESUMO

Iloprost, a stable prostaglandin I2 (PGI2) analog, can inhibit allergic inflammation in an ovalbumin (OVA)-induced asthma model via inhibition of airway dendritic cell (DC) function. However, the underlying mechanism of PGI2 signaling-mediated immunosuppression remains unclear. This study explored whether iloprost-treated DCs can suppress inflammation by promoting antigen-specific regulatory T cell (Treg) differentiation through PGI2-G-protein-coupled receptor (IP). We established an allergic lung inflammation model using a hydrogel biomaterial delivery system and observed that iloprost significantly suppressed OVA-induced Th2 lung inflammation and increased the frequency of OVA-specific Tregs in vivo. We further observed that iloprost-treated DCs displayed tolerogenic characteristics, including low inflammatory cytokine (IL-12, TNF-α, IL-6, IL-23) expression levels, high anti-inflammatory cytokine (IL-10) production, and a semimature phenotype. In addition, iloprost-treated DCs increased OVA-specific CD4+Foxp3+ T cell differentiation from naïve T cells in an IP-dependent pathway in vitro and in vivo. Blocking experiments showed that iloprost-treated DCs promoted Treg differentiation, at least in part, through programmed death ligand 1 (PD-L1), whereas iloprost-induced PD-L1 expression in DCs was through the IP receptor. Furthermore, iloprost treatment suppressed DC-mediated airway inflammation and increased the frequency of OVA-specific Tregs through PD-L1 in vivo. Taken together, these results show that PGI2-IP signaling mediated by iloprost in DCs may lead to immune tolerance, suggesting that the PGI2 analog has the potential to be applied therapeutically for tolerogenic DC immunotherapy in autoimmune diseases or allergic asthma.


Assuntos
Células Dendríticas/imunologia , Epoprostenol/análogos & derivados , Hipersensibilidade/tratamento farmacológico , Iloprosta/uso terapêutico , Linfócitos T Reguladores/imunologia , Animais , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Tolerância Imunológica , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Especificidade do Receptor de Antígeno de Linfócitos T
5.
Ultrason Sonochem ; 62: 104875, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31796329

RESUMO

Episodic release of bioactive compounds is often necessary for appropriate biological effects under specific physiological conditions. Here, we aimed to develop an injectable, biocompatible, and thermosensitive hydrogel system for ultrasound (US)-triggered drug release. An mPEG-PLGA-BOX block copolymer hydrogel was synthesized. The viscosity of 15 wt% hydrogel is 0.03 Pa*s at 25 °C (liquid form) and 34.37 Pa*s at 37 °C (gel form). Baseline and US-responsive in vitro release profile of a small molecule (doxorubicin) and that of a large molecule (FITC-dextran), from the hydrogel, was tested. A constant baseline release was observed in vitro for 7 d. When triggered by US (1 MHz, continuous, 0.4 W/cm2), the release rate increased by approximately 70 times. Without US, the release rate returned to baseline. Baseline and US-responsive in vivo release profile of doxorubicin was tested by subcutaneous injection in the back of mice and rats. Following injection into the subcutaneous layer, in vivo results also suggested that the hydrogels remained in situ and provided a steady release for at least 7 d; in the presence of the US-trigger, in vivo release from the hydrogel increased by approximately 10 times. Therefore, the mPEG-PLGA-BOX block copolymer hydrogel may serve as an injectable, biocompatible, and thermosensitive hydrogel system that is applicable for US-triggered drug release.


Assuntos
Materiais Biocompatíveis , Preparações de Ação Retardada , Dextranos/administração & dosagem , Doxorrubicina/administração & dosagem , Fluoresceína-5-Isotiocianato/análogos & derivados , Hidrogéis , Ondas Ultrassônicas , Animais , Linhagem Celular , Fluoresceína-5-Isotiocianato/administração & dosagem , Injeções Subcutâneas , Camundongos , Poliésteres/química , Polietilenoglicóis/química , Ratos
6.
Cell Transplant ; 28(12): 1560-1572, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31565957

RESUMO

Peripheral nerve regeneration following injury is often slow and impaired, which results in weakened and denervated muscle with subsequent atrophy. Human Wharton's jelly mesenchymal stem cells (hWJ-MSC) have potential regenerative properties which, however, remain unknown in mouse nerve recovery. This study investigated the effect of the topical application of hWJ-MSC onto repairing transected sciatic nerves in a mouse model. Human adipocyte-derived stem cells (hADSC) were used as a positive control. The sciatic nerve of BALB/c mice was transected at a fixed point and repaired under the microscope using 10-0 sutures. hWJ-MSC and hADSC were applied to the site of repair and mice were followed up for 1 year. The hWJ-MSC group had significantly better functional recovery of five-toe spread and gait angles compared with the negative control and hADSC groups. hWJ-MSC improved sciatic nerve regeneration in a dose-dependent fashion. The hWJ-MSC group had a better quality of regenerated nerve with an increased number of myelinated axons throughout. hWJ-MSC appear to be safe in mice after 1 year of follow-up. hWJ-MSC also expressed higher levels of neurotrophic factor-3, brain-derived neurotrophic factor, and glial-derived neurotrophic factor than hADSC. hWJ-MSC may promote better nerve recovery than hADSC because of this upregulation of neurotrophic factors.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Fatores de Crescimento Neural/biossíntese , Regeneração Nervosa , Nervo Isquiático , Regulação para Cima , Animais , Xenoenxertos , Humanos , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Nervo Isquiático/lesões , Nervo Isquiático/metabolismo , Nervo Isquiático/patologia
7.
Materials (Basel) ; 12(1)2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30621012

RESUMO

A mismatch of elastic modulus values could result in undesirable bone resorption around the dental implant. The objective of this study was to optimize direct metal laser sintering (DMLS)-manufactured Ti6Al4V dental implants' design, minimize elastic mismatch, allow for maximal bone ingrowth, and improve long-term fixation of the implant. In this study, DMLS dental implants with different morphological characteristics were fabricated. Three-point bending, torsional, and stability tests were performed to compare the mechanical properties of different designs. Improvement of the weaker design was attempted by augmentation with a longitudinal 3D-printed strut. The osseointegrative properties were evaluated. The results showed that the increase in porosity decreased the mechanical properties, while augmentation with a longitudinal weight-bearing strut can improve mechanical strength. Maximal alkaline phosphatase gene expression of MG63 cells attained on 60% porosity Ti6Al4V discs. In vivo experiments showed good incorporation of bone into the porous scaffolds of the DMLS dental implant, resulting in a higher pull-out strength. In summary, we introduced a new design concept by augmenting the implant with a longitudinal weight-bearing strut to achieve the ideal combination of high strength and low elastic modulus; our results showed that there is a chance to reach the balance of both biologic and mechanical demands.

8.
Histol Histopathol ; 33(12): 1271-1286, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29905361

RESUMO

OBJECTIVE: With the goal to explore a new approach to treat the early degenerative lesions of hyaline cartilage, we implanted in a porcine OA model a collagen-based scaffold containing chondroprogenitor cells derived from human bone marrow mesenchymal stem cells (hBM-MSCs). EXPERIMENTAL DESIGN: Porcine knee joints were subjected to anterior cruciate ligament (ACL) transection to surgically induce OA. After 4 months, the time necessary for the development of cartilage surface damage, animals were treated either with trephination bone plug wrapped with the chondroprogenic hBM-MSCs-embedded collagen scaffold or microfractures alone. Histological and histomorphometric evaluations were performed at 5 months after surgery. RESULTS: All animals subjected to ACL transection showed osteoarthritic changes including mild lateral femoral condyle or moderate medial femoral condyle ulcerations. After 14 days' chondrogenic induction, hBM-MSCs seeded onto the scaffold showed expression of chondroprogenitor markers such as SOX9 and COMP. At 5 months after the implantation, significant differences in the quality of the regenerated tissue were found between the hBM-MSCs-embedded scaffold group and the control group. Newly generated tissue was only observed at the site of implantation with the hBM-MSCs-embedded scaffolds. Furthermore, histological examination of the generated tissue revealed evidence of cartilage-like tissue with lacuna formation. In contrast, fibrous layers or fissures were formed on the surface of the control knee joint. CONCLUSIONS: This study shows that xenogenic hBM-MSC derived chondroprogenitor scaffolds can generate new cartilage tissue in porcine articular cartilage and have the potential as a useful treatment option for osteoarthritis.


Assuntos
Colágeno , Transplante de Células-Tronco Mesenquimais/métodos , Osteoartrite , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Cartilagem Articular , Condrogênese/fisiologia , Modelos Animais de Doenças , Xenoenxertos , Humanos , Suínos
9.
BMC Infect Dis ; 17(1): 516, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28743235

RESUMO

BACKGROUND: When bacteria colony persist within a biofilm, suitable drugs are not yet available for the eradication of biofilm-producing bacteria. The aim of this study is to study the effect of magnetic nano-particles-induced hyperthermia on destroying biofilm and promoting bactericidal effects of antibiotics in the treatment of osteomyelitis. METHODS: Sixty 12-weeks-old male Wistar rats were used. A metallic 18G needle was implanted into the bone marrow cavity of distal femur after the injection of Methicillin-sensitive Staphylococcus aureus (MSSA). All animals were divided into 5 different treatment modalities. The microbiological evaluation, scanning electron microscope examination, radiographic examination and then micro-CT evaluation of peri-implant bone resorption were analyzed. RESULTS: The pathomorphological characteristics of biofilm formation were completed after 40-days induction of osteomyelitis. The inserted implants can be heated upto 75 °C by magnetic heating without any significant thermal damage on the surrounding tissue. We also demonstrated that systemic administration of vancomycin [VC (i.m.)] could not eradicate the bacteria; but, local administration of vancomycin into the femoral canal and the presence of magnetic nanoparticles hyperthermia did enhance the eradication of bacteria in a biofilm-based colony. In these two groups, the percent bone volume (BV/TV: %) was significantly higher than that of the positive control. CONCLUSIONS: For the treatment of chronic osteomyelitis, we developed a new modality to improve antibiotic efficacy; the protection effect of biofilms on bacteria could be destroyed by magnetic nanoparticles-induced hyperthermia and therapeutic effect of systemic antibiotics could be enhanced.


Assuntos
Antibacterianos/farmacologia , Hipertermia Induzida/métodos , Osteomielite/terapia , Infecções Relacionadas à Prótese/terapia , Infecções Estafilocócicas/terapia , Animais , Biofilmes , Hipertermia Induzida/instrumentação , Nanopartículas de Magnetita , Masculino , Staphylococcus aureus Resistente à Meticilina , Osteomielite/microbiologia , Ratos Wistar , Infecções Estafilocócicas/microbiologia , Resultado do Tratamento , Vancomicina/farmacologia
10.
Sci Rep ; 4: 5600, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25034369

RESUMO

Tissue scaffolds provide a framework for living tissue regeneration. However, traditional tissue scaffolds are exogenous, composed of metals, ceramics, polymers, and animal tissues, and have a defined biocompatibility and application. This study presents a new method for obtaining a tissue scaffold from blood albumin, the major protein in mammalian blood. Human, bovine, and porcine albumin was polymerised into albumin polymers by microbial transglutaminase and was then cast by freeze-drying-based moulding to form albumin tissue scaffolds. Scanning electron microscopy and material testing analyses revealed that the albumin tissue scaffold possesses an extremely porous structure, moderate mechanical strength, and resilience. Using a culture of human mesenchymal stem cells (MSCs) as a model, we showed that MSCs can be seeded and grown in the albumin tissue scaffold. Furthermore, the albumin tissue scaffold can support the long-term osteogenic differentiation of MSCs. These results show that the albumin tissue scaffold exhibits favourable material properties and good compatibility with cells. We propose that this novel tissue scaffold can satisfy essential needs in tissue engineering as a general-purpose substrate. The use of this scaffold could lead to the development of new methods of artificial fabrication of autogenic tissue substitutes.


Assuntos
Albumina Sérica/química , Tecidos Suporte/química , Animais , Autoenxertos , Proteínas de Bactérias/química , Sobrevivência Celular , Células Cultivadas , Liofilização , Humanos , Células-Tronco Mesenquimais/fisiologia , Polimerização , Streptomyces/enzimologia , Sus scrofa , Resistência à Tração , Engenharia Tecidual , Transglutaminases/química
11.
Biofabrication ; 4(4): 045001, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23013844

RESUMO

Ferritin is an iron storage protein that is often used to coat metallic nanoparticles, such as iron oxide nanoparticles (IONPs). However, the synthesis and biocompatibility of ferritin-coated IONPs remain unclear. Therefore, this study reports the synthesis of a ferritin gene cloned and expressed from Helicobacter pylori (HPFn). The ferroxidase activity of the synthase HPFn was used for the de novo synthesis of HPFn-coated IONPs under mild conditions. Gel filtration chromatography and transmission electron microscopy analyses demonstrated that the core-shell structure of both the 5.0 nm IONP nanocore and the 12.4 nm HPFn shell were correctly assembled. The cellular uptake of mouse macrophage cells (RAW 264.7 cells) has shown that only a few HPFn-coated IONPs (3%) were taken up after 24 h of incubation. This study compares the biocompatibility of HPFn-coated IONPs, superparamagnetic iron oxide nanoparticles (SPIOs) and ferric salt (ferric ammonium citrate) in respect to cell growth inhibition, reactive oxygen species generation and pro-inflammatory cytokine TNF-α release. Assessment results showed that the responses elicited by HPFn-coated IONPs were similar to those elicited by SPIO treatment but milder than those elicited by ferric salt treatment. This accounts for the notion that ferritin-coated IONPs are biocompatible iron agents. These findings show that the ferroxidase activity of ferritin can be used to synthesize biocompatible IONPs. The favorable properties of HPFn-coated IONPs suggest that they can be used as a non-macrophage contrast agent through further surface conjugation.


Assuntos
Materiais Biocompatíveis/química , Ferritinas/metabolismo , Helicobacter pylori/enzimologia , Nanopartículas de Magnetita/química , Animais , Materiais Biocompatíveis/metabolismo , Biotecnologia/métodos , Linhagem Celular , Ceruloplasmina/metabolismo , Ferritinas/química , Helicobacter pylori/metabolismo , Concentração de Íons de Hidrogênio , Camundongos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
Nanomedicine ; 8(8): 1345-54, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22406186

RESUMO

UNLABELLED: Non-invasive in vivo tracking of T-cells by magnetic resonance imaging (MRI) can lead to a better understanding of many pathophysiological situations, including AIDS, cancer, diabetes, graft rejection. However, an efficient MRI contrast agent and a reliable technique to track non-phagocytic T-cells are needed. We report a novel superparamagnetic nano-sized iron-oxide particle, IOPC-NH2 series particles, coated with polyethylene glycol (PEG), with high transverse relaxivity (250 s(-1) mM(-1)), thus useful for MRI studies. IOPC-NH2 particles are the first reported magnetic particles that can label rat and human T-cells with over 90% efficiency, without using transfection agents, HIV-1 transactivator peptide, or electroporation. IOPC-NH2 particles do not cause any measurable effects on T-cell properties. Infiltration of IOPC-NH2-labeled T-cells can be detected in a rat model of heart-lung transplantation by in vivo MRI. IOPC-NH2 is potentially valuable contrast agents for labeling a variety of cells for basic and clinical cellular MRI studies, e.g., cellular therapy. FROM THE CLINICAL EDITOR: In this study, a novel PEG coated superparamagnetic nano-sized iron-oxide particle was investigated as a T-cell labeling agent for MRI studies. The reported particles can label T-cells with over 90% efficiency, without using transfection agents, HIV-1 transactivator peptide, or electroporation, therefore may enable more convenient preclinical call labeling studies.


Assuntos
Rastreamento de Células , Meios de Contraste , Compostos Férricos/química , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/química , Animais , Transplante de Coração-Pulmão , Humanos , Células Jurkat , Masculino , Polietilenoglicóis/química , Radiografia , Ratos , Medicina Regenerativa , Linfócitos T/citologia , Linfócitos T/diagnóstico por imagem
13.
Mol Imaging Biol ; 13(5): 825-39, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20862612

RESUMO

PURPOSE: In this study, we investigated the labeling efficiency and magnetic resonance imaging (MRI) signal sensitivity of a newly synthesized, nano-sized iron oxide particle (IOP) coated with polyethylene glycol (PEG), designed by Industrial Technology Research Institute (ITRI). PROCEDURES: Macrophages, bone-marrow-derived dendritic cells, and mesenchymal stem cells (MSCs) were isolated from rats and labeled by incubating with ITRI-IOP, along with three other iron oxide particles in different sizes and coatings as reference. These labeled cells were characterized with transmission electron microscopy (TEM), light and fluorescence microscopy, phantom MRI, and finally in vivo MRI and ex vivo magnetic resonance microscopy (MRM) of transplanted hearts in rats infused with labeled macrophages. RESULTS: The longitudinal (r (1)) and transverse (r (2)) relaxivities of ITRI-IOP are 22.71 and 319.2 s(-1) mM(-1), respectively. TEM and microscopic images indicate the uptake of multiple ITRI-IOP particles per cell for all cell types. ITRI-IOP provides sensitivity comparable or higher than the other three particles shown in phantom MRI. In vivo MRI and ex vivo MRM detect punctate spots of hypointensity in rejecting hearts, most likely caused by the accumulation of macrophages labeled by ITRI-IOP. CONCLUSION: ITRI-IOP, the nano-sized iron oxide particle, shows high efficiency in cell labeling, including both phagocytic and non-phagocytic cells. Furthermore, it provides excellent sensitivity in T(2)*-weighted MRI, and thus can serve as a promising contrast agent for in vivo cellular MRI.


Assuntos
Compostos Férricos/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas Metálicas , Animais , Células Cultivadas , Citometria de Fluxo , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Tamanho da Partícula , Ratos
14.
Protein Expr Purif ; 76(1): 54-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20826215

RESUMO

Human vascular endothelial growth factor isoform 165 (VEGF165) is the first known member belonging to the VEGF protein family that plays a critical role in new blood vessel formation in vivo. This study presents a new protocol with optimized conditions for rapidly producing untagged recombinant and biological active human VEGF165 (rhVEGF165) using Escherichia coli cells. Protein was isolated from inclusion bodies, purified by gel filtration and ion exchange chromatography, and subjected to protein refolding and renaturation. The biological activity of rhVEGF165 is comparable with VEFG from eukaryotic source according to human umbilical vein endothelial cells (HUVEC) proliferation assay. Therefore, the present procedures provide a fast and easy way to produce this therapeutic protein.


Assuntos
Proteínas Recombinantes/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese , Escherichia coli , Humanos , Corpos de Inclusão/química , Redobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/isolamento & purificação
15.
J Immunol ; 185(9): 5468-75, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20889541

RESUMO

The standard hepatitis B surface Ag (HBsAg) vaccine fails to induce anti-hepatitis B surface Abs in 5-10% of healthy subjects, a phenomenon known as HBsAg nonresponsiveness, which is closely related to HLA class II alleles and impaired Th cell responses to HBsAg in these subjects. We hypothesized that GM-CSF, a potent adjuvant in enhancing the Ag-presentation activity of APCs, might help to generate Th cell responses in nonresponders, subsequently providing help for B cells to produce anti-hepatitis B surface Abs. We used a thermosensitive biodegradable copolymer (hydrogel) system to codeliver HBsAg and GM-CSF to achieve maximal local cytokine activity at the injection site. In responder mouse strains, hydrogel-formulated HBsAg plus GM-CSF (Gel/HBs+GM) vaccine elicited much greater anti-hepatitis B surface Ab titers and Th cell proliferative responses than a commercial aluminum-formulated HBsAg vaccine or free HBsAg. The adjuvant effect of the Gel/HBs+GM vaccine was dependent upon the local release of GM-CSF. More importantly, the Gel/HBs+GM vaccine elicited high HBsAg-specific Ab titers and Th cell responses in B10.M mice, a mouse strain that does not respond to the current HBsAg vaccine because of its H-2 haplotype. Analysis of the draining lymph nodes of Gel/HBs+GM vaccine-treated mice revealed an elevated number of CD11c(+) dendritic cells showing enhanced expression of MHC class II and a variety of costimulatory molecules. These results demonstrate that hydrogel-formulated GM-CSF might represent a simple and effective method to generate next-generation hepatitis B virus vaccines for inducing anti-hepatitis B surface Abs in nonresponders.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Células Dendríticas/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Antígenos de Superfície da Hepatite B/administração & dosagem , Vacinas contra Hepatite B/imunologia , Hidrogel de Polietilenoglicol-Dimetacrilato/administração & dosagem , Animais , Anticorpos Antivirais/imunologia , Resistência a Medicamentos/genética , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Linfócitos T Auxiliares-Indutores/imunologia , Vacinação/métodos
16.
J Proteome Res ; 9(3): 1302-22, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20052998

RESUMO

The transformation of a normal cell into a cancer cell has been correlated with alterations in gene regulation and protein expression. To identify altered proteins and link them to the tumorigenesis of breast cancer, we have distinguished normal breast cells (MCF-10A) from noninvasive breast cancer cells (MCF-7) and invasive breast cancer cells (MB-MDA-231) to identify potential breast cancer markers in transformed breast cells. Using the 2D-DIGE and MALDI-TOF MS techniques, we quantified and identified differentially expressed extracellular secreted proteins and total cellular proteins across MCF-7, MB-MDA-231 and MCF-10A. The proteomic analysis of the secreted proteins identified 50 unique differentially expressed proteins from three different media. In addition, 133 unique differentially expressed proteins from total cellular proteins were also identified. Note that 14 of the secreted proteins and 51 of the total cellular proteins have not been previously reported in breast cancer research. Some of these unreported proteins have been examined in other breast cancer cell lines and have shown positive correlations with 2D-DIGE data. In summary, this study identifies numerous putative breast cancer markers from various stages of breast cancer. The results of this study may aid in developing proteins identified as useful diagnostic and therapeutic candidates in research on cancer and proteomics.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Eletroforese em Gel Bidimensional/métodos , Proteínas de Neoplasias/análise , Proteoma/análise , Proteômica/métodos , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Transformada , Linhagem Celular Tumoral , Transformação Celular Neoplásica/metabolismo , Feminino , Imunofluorescência , Humanos , Immunoblotting , Proteínas de Neoplasias/metabolismo , Proteoma/metabolismo , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
17.
Surg Neurol ; 72 Suppl 2: S50-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19944826

RESUMO

BACKGROUND: Brain tissue scarring (gliosis) was believed to be the major cause of epileptic focus after brain injury, and prevention of scarring could reduce the incidence of seizure. We tried the HA coating onto the cortical brain defect of Spraque-Dawley rats to reduce the marginal glial scarring. METHODS: A 4 x 2 x 2 mm(3) cortical defect was created in the brain of Spraque-Dawley rats. Three percent HA gel was coated onto the lesion for the experimental groups and normal saline solutions for the control groups. The brain was retrieved 4, 8, and 12 weeks after treatment. The brains were then sectioned and processed for H&E and GFAP staining, and the thickness of the scarring and the number of GFAP+ cells were analyzed. RESULTS: The thickness of cutting marginal gliosis was significantly decreased in the HA groups. The 12-week HA group showed the smallest thickness of gliosis, whereas the 12-week control group exhibited the largest thickness of gliosis. The significant difference in the thickness of gliosis was also noted between the HA and the control groups 8 weeks after treatment. The number of GFAP+ cells was also significantly decreased in the HA groups when compared to the respective control group 4, 8, and 12 weeks after the surgery. CONCLUSION: The results support the hypothesis that HA inhibits glial scarring not only by decreasing the thickness of gliosis but also by reducing the number of the glial cells. Furthermore, our results suggest that HA might be used to reduce glial scar formation in central nervous system surgery, which subsequently prevents the post-operation or posttraumatic seizure incidence.


Assuntos
Lesões Encefálicas/complicações , Cicatriz/tratamento farmacológico , Gliose/tratamento farmacológico , Ácido Hialurônico/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Lesões Encefálicas/fisiopatologia , Cicatriz/fisiopatologia , Cicatriz/prevenção & controle , Modelos Animais de Doenças , Epilepsia/tratamento farmacológico , Epilepsia/etiologia , Epilepsia/prevenção & controle , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Gliose/fisiopatologia , Gliose/prevenção & controle , Ácido Hialurônico/metabolismo , Ácido Hialurônico/uso terapêutico , Masculino , Degeneração Neural/etiologia , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
18.
J Neuropathol Exp Neurol ; 64(7): 576-87, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16042309

RESUMO

We established histopathologic and neurophysiologic approaches to examine whether different designs of polycaprolactone-engineered nerve conduits (hollow vs. laminated) could promote nerve regeneration as autologous grafts after transection of sciatic nerves. The assessments included morphometric analysis at the level of sciatic nerve, neuromuscular junction (NMJ) and gastrocnemius muscle, and nerve conduction studies on sciatic nerves. Six months after nerve grafting, the nerve fiber density in the hollow-conduit group was similar to that in the autologous-graft group; the laminated-conduit group only achieved approximately 20% of these values. The consequences of these differences were reflected in nerve growth into muscular targets; this was demonstrated by combined cholinesterase histochemistry for NMJ and immunohistochemistry for nerve fibers innervating NMJ with an axonal marker, protein gene product 9.5. Hollow conduits had similar index of NMJ innervation as autologous grafts; the values were higher than those of laminated conduits. Among the 3 groups there were same patterns of differences in the cross-sectional area of muscle fibers and amplitudes of compound muscle action potential. These results indicate that hollow conduits were as efficient as autologous grafts to facilitate nerve regeneration, and provide a multidisciplinary approach to quantitatively evaluate muscular reinnervation after nerve injury.


Assuntos
Músculo Esquelético/inervação , Regeneração Nervosa/fisiologia , Poliésteres , Próteses e Implantes , Nervo Isquiático/fisiologia , Potenciais de Ação/fisiologia , Animais , Materiais Biocompatíveis , Colinesterases/metabolismo , Eletrofisiologia , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Transmissão , Junção Neuromuscular/fisiologia , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/transplante , Nervo Isquiático/ultraestrutura , Transplante Homólogo
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