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1.
Biomed Mater ; 19(3)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38537374

RESUMO

Among various biomaterials employed for bone repair, composites with good biocompatibility and osteogenic ability had received increasing attention from biomedical applications. In this study, we doped selenium (Se) into hydroxyapatite (Se-HA) by the precipitation method, and prepared different amounts of Se-HA-loaded poly (amino acid)/Se-HA (PAA/Se-HA) composites (0, 10 wt%, 20 wt%, 30 wt%) byin-situmelting polycondensation. The physical and chemical properties of PAA/Se-HA composites were characterized by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and their mechanical properties. XRD and FT-IR results showed that PAA/Se-HA composites contained characteristic peaks of PAA and Se-HA with amide linkage and HA structures. DSC and TGA results specified the PAA/Se-HA30 composite crystallization, melting, and maximum weight loss temperatures at 203.33 °C, 162.54 °C, and 468.92 °C, respectively, which implied good thermal stability. SEM results showed that Se-HA was uniformly dispersed in PAA. The mechanical properties of PAA/Se-HA30 composites included bending, compressive, and yield strengths at 83.07 ± 0.57, 106.56 ± 0.46, and 99.17 ± 1.11 MPa, respectively. The cellular responses of PAA/Se-HA compositesin vitrowere studied using bone marrow mesenchymal stem cells (BMSCs) by cell counting kit-8 assay, and results showed that PAA/Se-HA30 composites significantly promoted the proliferation of BMSCs at the concentration of 2 mg ml-1. The alkaline phosphatase activity (ALP) and alizarin red staining results showed that the introduction of Se-HA into PAA enhanced ALP activity and formation of calcium nodule. Western blotting and Real-time polymerase chain reaction results showed that the introduction of Se-HA into PAA could promoted the expression of osteogenic-related proteins and mRNA (integrin-binding sialoprotein, osteopontin, runt-related transcription factor 2 and Osterix) in BMSCs. A muscle defect at the back and a bone defect at the femoral condyle of New Zealand white rabbits were introduced for evaluating the enhancement of bone regeneration of PAA and PAA/Se-HA30 composites. The implantation of muscle tissue revealed good biocompatibility of PAA and PAA/Se-HA30 composites. The implantation of bone defect showed that PAA/Se-HA30 composites enhanced bone formation at the defect site (8 weeks), exhibiting good bone conductivity. Therefore, the PAA-based composite was a promising candidate material for bone tissue regeneration.


Assuntos
Durapatita , Selênio , Animais , Coelhos , Durapatita/química , Aminoácidos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Regeneração Óssea , Osteogênese , Osteoblastos , Proliferação de Células
2.
Biomater Adv ; 154: 213638, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37812984

RESUMO

The treatment and reconstruction of large or critical size bone defects is a challenging clinical problem. Additive manufacturing breaks the technical difficulties of preparing complex conformation and anatomically matched personalized porous tantalum implants, but the ideal pore structure for 3D-printed porous tantalum in critical bone defect repair applications remains unclear. Guiding appropriate bone tissue regeneration by regulating proper pore size-pore distribution-pore geometry-porosity is a challenge for its fabrication and application. We fabricated porous tantalum (PTa) scaffolds with six different combinations of pore structures using powder bed laser melting (L-PBF) technology. In vitro biological experiments were conducted to systematically investigate the effects of pore structure characteristics on osteoblast behaviors, showing that the bionic trabecular structure with both large and small poress facilitated cell permeation, proliferation and differentiation compared to the cubic structure with uniform pore sizes. The osteogenesis of PTa with different porosity of trabecular structures was further investigated by a rabbit condyle critical bone defect model. Synthetically, T70% up-regulated the expression of osteogenesis-related genes (ALP, COLI, OCN, RUNX-2) and showed the highest bone ingrowth area and bone contact rate in vivo after 16 weeks, with the best potential for critical bone defect repair. Our results suggested that the bionic trabecular structure with a pore size distribution of 200-1200 µm, an average pore size of 700 µm, and a porosity of 70 % is the best choice for repairing critical bone defects, which is expected to guide the clinical application of clinical 3D-printed PTa scaffolds.


Assuntos
Osteogênese , Tantálio , Animais , Coelhos , Porosidade , Tantálio/farmacologia , Osteogênese/genética , Osso e Ossos , Impressão Tridimensional
3.
Artigo em Inglês | MEDLINE | ID: mdl-36755394

RESUMO

Immunomodulatory biomaterials have emerged as promising treatment agents for bone defects. However, it is unclear how such biomaterials control immune cell behaviors to facilitate large-segment bone defect repair. Herein, we fabricated biphasic calcium phosphate ceramics with nanowhisker structures to explore the immunoregulation features and influence on large-segment bone defect repair. We found that the nanowhisker structures markedly facilitated large-segment bone defect repair by promoting bone regeneration and scaffold resorption. Our in vitro experiment and transcriptomic analysis showed that mechanical stress derived from nanowhisker structures may activate the transcription of Egr-1 to induce early switch of macrophage phenotype to M2, which could not only facilitate osteogenic differentiation of BMSCs but also enhance the expression of osteoclast differentiation-regulating genes of M2 macrophage. In vivo study showed that the nanowhisker structures relieved local inflammatory responses by inducing early switch of macrophage phenotype from M1 to M2, which resulted in accelerated osteoclastogenesis for biomaterial resorption and osteogenesis for ectopic bone formation. Hence, we presume that nanowhisker structures may orchestrate bone formation and material resorption coupling to facilitate large-segment bone defect repair by controlling the switch of macrophage phenotype. This study provides new insight into the designing of immunomodulatory tissue engineering biomaterials for treating large-segment bone defects.

4.
Molecules ; 27(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36431809

RESUMO

Destruxin A (DA), a hexa-cyclodepsipeptidic mycotoxin produced by the entomopathogenic fungus Metarhizium anisopliae, has insecticidal activity, but its molecular mechanism of action is still not clear. Three proteins with modification-related functions, calreticulin (BmCRT), dipeptidyl peptidase Ⅲ (BmDPP3), and protein disulfide isomerase A5 (BmPDIA5), were selected to verify the interactions with DA in this study. The kinetic data of the interactions were measured by surface plasmon resonance (SPR) and bio-layer interferometry (BLI) in vitro. The KD values of DA with BmCRT, BmDPP3, and BmPDIA5 ranged from 10-4 to 10-5 mol/L, which suggested that the three proteins all had fairly strong interactions with DA. Then, it was found that DA in a dose-dependent manner affected the interactions of the three proteins with their partners in insect two-hybrid tests in SF-9 cells. Furthermore, the results of enzyme activities by ELISA indicated that DA could inhibit the activity of BmDPP3 but had no significant effect on BmPDIA5. In addition, DA induced the upregulation of BmDPP3 and the downregulation of BmCRT. The results prove that BmCRT, BmDPP3, and BmPDIA5 are all binding proteins of DA. This study might provide new insights to elucidate the molecular mechanism of DA.


Assuntos
Bombyx , Depsipeptídeos , Animais , Ressonância de Plasmônio de Superfície , Regulação para Baixo
5.
J Mater Chem B ; 10(7): 1063-1076, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35076052

RESUMO

Adhesives have attracted extensive attention in biomedical applications in recent years. However, the development of adhesives with strong adhesion in both dry and underwater conditions and antibacterial properties is still a challenge. Herein, a biomimetic adhesive (DP@TA/Gel) was developed based on the adhesion mechanism of mussel in water, from adhesion and solidification to avoiding excessive oxidization processes. DP@TA/Gel exhibited rapid strong nonspecific adhesiveness to diverse materials including wood (485 kPa) metal (507 kPa), plastic (74 kPa), and even fresh biological tissue (39 kPa) in dry conditions. Specially, owing to its biomimetic design, DP@TA/Gel could imitate the mussel adhesion mechanism underwater, endowing it with robust (38 kPa), highly repeatable (at least 15 times) and long-term (at least 120 h) stable adhesion even in underwater conditions. Remarkably, DP@TA/Gel also exhibited high adhesiveness in various water environments, including seawater, and a wide range of pH (3-11) and NaCl concentration (0.9-10%) solutions without any stimulus. In addition, DP@TA/Gel showed excellent biocompatibility and antibacterial properties. Thus, the DP@TA/Gel adhesive has appealing potential biomedical applications such as sutureless wound closure and as a tissue adhesive.


Assuntos
Adesivos , Bivalves , Adesividade , Adesivos/química , Adesivos/farmacologia , Animais , Antibacterianos/farmacologia , Biomimética , Água/química
6.
Environ Toxicol ; 36(5): 800-810, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33347706

RESUMO

Skin cancer is the commonly found type, which contributes to 40% of whole cancer incidences worldwide. Dieckol is an active compound occurs in the marine algae with many biological benefits. In this exploration, we intended to investigate the therapeutic potency of dieckol against the 7,12-dimethylbenz(a)anthracene (DMBA)-triggered skin carcinogenesis in mice. The skin cancer was stimulated to the animals via injecting the 25 µg of DMBA in 100 µL of acetone in shaved dorsal portion along with the 30 mg/kg of dieckol supplementation for 25 week. The antioxidant enzymes and phase-I and -II detoxifying enzymes in the test animals were inspected via standard protocols. Pro-inflammatory markers (IL-6, IL-1ß, and TNF-α) level was examined via ELISA kits and the expression of inflammatory molecular markers like p-NF-ƙB, IƙBα and p-IƙBα were studied through western blotting. The expression status of pro- and anti-apoptotic proteins (p53, Bax, Bcl-2, caspase-3, caspase-9, COX-2, TGF-ß1) was investigated via real-time polymerase chain reaction (RT-PCR). Our results revealed that the 30 mg/kg of dieckol supplementation noticeably regained the body and liver weight and also diminished the tumor incidence in the DMBA-incited animals. Dieckol treatment exhibited an enhanced antioxidants (SOD, CAT, GPx, and GSH) and reduced phase-I enzymes Cyt-p450 and Cyt-b5 in the DMBA-induced animals. Dieckol also diminished the pro-inflammatory modulators like IL-6, IL-1ß and TNF-α. Western blotting result evidenced that the dieckol was inhibited the IƙB/NF-ƙB signaling pathway. RT-PCR study proved the enhanced expression of pro-apoptotic protein (p53, Bax, caspase-3 and -9) in the dieckol treated animals. Histological study also confirmed the therapeutic benefits of Dieckol. Altogether with these findings, it was clear that the dieckol has appreciably allayed the DMBA activated skin tumorigenesis in the mice and it could be a promising agent to treat the human skin cancer in future.


Assuntos
Antioxidantes , Neoplasias Cutâneas , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Antracenos , Benzofuranos , Biomarcadores , Carcinogênese , Camundongos , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/prevenção & controle
7.
Colloids Surf B Biointerfaces ; 187: 110641, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31759778

RESUMO

Rapid hemostasis is crucial to saving the lives of traumatic patients in emergency medical treatment. To improve the hemostatic performance of the gelatin microspheres (GMs) in vivo and in vitro, in the study, porous gelatin microspheres (PGMs) were prepared through water-in-oil emulsion method combined with vacuum freeze-drying after cross-linking with glutaraldehyde and prefreeze in liquid nitrogen. Owing to the porous structure and rough surface, the obtained PGMs were effective to induce red blood cells aggregation and promote fibrin generation, which led to improved hemostatic potential than GMs in blood coagulation time, whole blood clotting rate, and the hemostatic efficiency of rabbit liver wound and ear vein cut models tests. The potent hemostatic effect of the PGMs could be attributed to the synergistic effects of the physiological blood coagulation activated by negatively charged surface and physical barriers reinforced by fibrin. Moreover, PGMs with high water absorption rate and porous structure showed better hemostatic performance than commercial hemostatic powder (chitosan hemostasis power and Yunnan Baiyao) in vitro and in vivo. Cytotoxicity tests with bone marrow mesenchymal stem cells of murine showed that PGMs with excellent cytocompatibility were conducive to cell proliferation. Therefore, it could be concluded that PGMs were more suitable for rapid hemostasis than GMs and had a great potential for hemostatic applications.


Assuntos
Gelatina/farmacologia , Hemostáticos/farmacologia , Microesferas , Animais , Coagulação Sanguínea/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quitosana/farmacologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/ultraestrutura , Hemostasia/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Porosidade , Coelhos , Eletricidade Estática , Propriedades de Superfície , Fatores de Tempo
8.
Macromol Biosci ; 20(2): e1900303, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31867845

RESUMO

Self-healing hydrogels as wound dressings still face challenges in infection prevention, especially in the dressing of mass wounds, due to their inflexibility and the slow formation of the protective film on the wound. Therefore, designing a spray-filming (rapid-forming) hydrogel that can serve as a bacterial barrier is of particular significance in the development of wound dressings. Here, a self-healing hydrogel based on adipic acid dihydrazide-modified gelatin (Gel-ADH) and monoaldehyde-modified sodium alginate(SA-mCHO) is prepared. Using dynamic, Schiff base bonds, the hydrogels exhibit excellent self-healing properties. Moreover, the gelation time of SA-mCHO/Gel-ADH (SG) hydrogels is shortened to 2-21 s, resulting in rapid filming by spraying the two precursor solutions. In addition, the rapid spray-filming ability might offer sufficient flexibility and rapidity for dealing with mass and irregular wounds. Notably, the bacterial barrier experiments show that the SG hydrogel films could form an effective barrier to Staphylococcus aureus and Candida albicans for 12 h. Therefore, SG hydrogels could be used in wound dressings and they show great promise in applications associated with mass and irregular traumas.


Assuntos
Alginatos/química , Bandagens , Candida albicans/crescimento & desenvolvimento , Gelatina/química , Hidrogéis/química , Membranas Artificiais , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Camundongos
9.
Int J Nanomedicine ; 14: 3331-3343, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31123401

RESUMO

Background and methods: A Cu-doped composite scaffold of nano calcium-deficient hydroxyapatite (n-CDHA)/multi(amino acid) copolymer (MAC) was prepared. The structure, porosity, morphology and compressive strength of the scaffolds were characterized, the in vitro degradability in phosphate-buffered solution (PBS) and cell responses to the scaffolds were investigated, and in vivo stimulation of bone formation were analyzed. Results: The scaffolds showed the compressive strength of approximately 12 MPa and total porosity of about 81%. Weight loss of the composite scaffolds was 63% after 16-week immersion in PBS. Cu release in scaffolds showed a marked dependence on the initial amount in the scaffolds over time. Cu-doped n-CDHA/MAC scaffolds with the content of Cu 0.5% and 1% in mass ratio showed better cell responses to proliferation and differentiation of rat bone marrow stromal cells (rBMSCs) than that with no Cu. After 12-week implantation in rabbits, 1% Cu-doped n-CDHA/MAC showed better ability of angiogenesis and osteogenesis compared to 0% Cu-doped n-CDHA/MAC. Conclusion: The 1% Cu-doped n-CDHA/MAC composite scaffold showed good capacity of angiogenesis and osteogenesis, and the Cu showed positive effects on cell growth and osteogenesis. And it has potential to be used as bone regeneration scaffolds.


Assuntos
Aminoácidos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/fisiologia , Cobre/farmacologia , Durapatita/farmacologia , Nanopartículas/química , Polímeros/química , Alicerces Teciduais/química , Fosfatase Alcalina/metabolismo , Animais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Força Compressiva , Implantes Experimentais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Porosidade , Coelhos , Ratos , Microtomografia por Raio-X
10.
Front Psychiatry ; 10: 135, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30984036

RESUMO

Objective: Repetitive transcranial magnetic stimulation (rTMS) has been applied to dorsolateral prefrontal cortex (DLPFC) to improve cognitive function of patients with schizophrenia (SZs). The aim of this meta-analysis was to evaluate whether a high-frequency rTMS course could enhance cognitive function in SZs. Methods: Studies published in PubMed, Cochrane Library, Embase, ScienceDirect, and Web of science were searched until April 2018. The search terms included: "repetitive transcranial magnetic stimulation" or "Rtms," "SZ," or "schizophrenia," and "neuro-cognition" or "neurocognitive performance" or "cognitive effects" or "cognitive" or "cognition" or "working memory" or "executive function" or "language function" or "processing speed," After screening the literatures according to inclusion and exclusion criteria, extracting data, and evaluating the methodological quality of the included studies, a meta-analysis was performed using RevMan 5.3 software (The Cochrane Collaboration, USA). Results: A total of 9 studies on cognitive dysfunction of SZs were included and involved 351 patients. A significant efficacy of high-frequency rTMS on working memory in SZs was found compared to sham stimulation [p = 0.009, standardized mean difference (SMD) = 0.34]. Specifically, rTMS treatment positioned on the left DLPFC, with a total pluses <30,000 was more significantly more effective in improving the working memory (SMD = 0.33, p = 0.03). No improvement was found in other cognitive domains such as executive function, attention, processing speed, and language function. For the follow-up observations, high-frequency rTMS had long-lasting sustained effects on working memory (SMD = 0.45, p = 0.01) and language function (SMD = 0.77, p = 0.02) in SZs. Conclusions: High-frequency rTMS over the left DLPFC with a total pulses <30,000 stimulation could significantly improve working memory in SZs for an extended period of time.

11.
Alzheimer Dis Assoc Disord ; 33(2): 170-178, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31033517

RESUMO

OBJECTIVE: The purpose of this meta-analysis was to evaluate the therapeutic effect of transcranial direct current stimulation (tDCS) on mild to moderate Alzheimer disease (AD) patients. MATERIALS AND METHODS: PubMed, Embase, Web of Science, and Cochrane Library were searched until April 2018. The primary cognitive outcomes were extracted from included articles. A crude standardized mean difference with 95% CI was calculated by using fixed or random effect models. RESULTS: Seven studies with 146 patients were included in this meta-analysis. The pooled result showed that tDCS significantly improved cognitive function of AD patients (standardized mean difference=0.37; 95% CI, 0.09-0.65; P=0.01). Subgroup analyses showed that: a single session of tDCS was significantly effective (P<0.05) whereas repeated sessions of tDCS was not lower current density (0.06 mA/cm) (P>0.05) but not higher current density (0.08 mA/cm) significantly improved cognitive performance; stimulating the temporal cortex (P<0.05) but not the left dorsal lateral prefrontal cortex significantly improved cognitive function of AD patients; and improved cognitive function occurred in the group with higher education (P<0.05) but not in the group with lower education. CONCLUSIONS: Current evidence suggests that tDCS has a beneficial effect in mild to moderate AD patients. We must be cautious about the results of subgroup analysis given small sample sizes, and further well-designed studies with larger sample size are required to verify these results.


Assuntos
Doença de Alzheimer/terapia , Cognição/fisiologia , Estimulação Transcraniana por Corrente Contínua , Doença de Alzheimer/fisiopatologia , Humanos
12.
J Biomed Mater Res B Appl Biomater ; 107(7): 2365-2377, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30689278

RESUMO

In this work, novel bioactive organic-inorganic composite bone cements consisting of tricalcium silicate (C3 S), sodium alginate (SA), and calcium sulfate hemihydrate (CS) were successfully fabricated for the first time via a special method designing material composition and internal structure simultaneously, which was intended to enhance mechanical performance by combining progressive hydration process of C3 S with distinctive gelation capacity of SA and further improve degradability and self-setting properties with the addition of CS. Depending on the synergistic combination of hydration and gelation, the C3 S/SA/CS composite cements (45/45/10 wt %) obtained extremely higher compressive strength up to 92.41 MPa as compared with each single component. The reinforcing mechanisms involving interfacial interaction and interior microstructure were proposed to explain this enhancement phenomenon. Additionally, the final setting time could be reduced from 68 min to 21 min with the increasing CS content. The composite cements possessed good apatite mineralization ability in simulated body fluid solution and moderate degradation rate in phosphate buffer solution. What's more, the composite cements exhibited excellent cytocompatibility and increased proliferation of rat bone-marrow stem cells. This study could provide guidelines for the preparation of bioactive composite cements with enhanced mechanical performance, which may be suitable for load-bearing bone repair. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2365-2377, 2019.


Assuntos
Cimentos Ósseos , Células da Medula Óssea/metabolismo , Força Compressiva , Teste de Materiais , Alginatos/química , Alginatos/farmacologia , Animais , Cimentos Ósseos/química , Cimentos Ósseos/farmacologia , Células da Medula Óssea/citologia , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Sulfato de Cálcio/química , Sulfato de Cálcio/farmacologia , Ratos , Silicatos/química , Silicatos/farmacologia
13.
J Biomater Sci Polym Ed ; 30(2): 107-121, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30518309

RESUMO

The aim of this study was to evaluate the thermal properties and in vivo interface performance of poly(amino acid) (PAA) and a composite containing PAA, hydroxyapatite (HA), and calcium sulfate (CS), with respect to their suitability for skull repair. Biocompatibility was evaluated by implantation of materials into muscles of rabbits for eight weeks. Skull repair was assessed by implanting PAA, the compact PAA/HA/CS composite (c-PAA/HA/CS), and a one-side-porous PAA/HA/CS composite (p-PAA/HA/CS) into rabbit calvarial defects. The results showed that the PAA/HA/CS composite possessed good heat resistance and possessed excellent biocompatibility and osteoconductivity. Guided bone regeneration and calvarial repair were observed, with excellent integration between calvarial tissue and implant. The p-PAA/HA/CS composite performed best in terms of stability and bone bonding between implant and host bone tissue. Thus, the present work provides new information for the potential use of osteoconductive PAA/HA/CS composites with a macrostructure in calvarial bone repair.


Assuntos
Aminoácidos/química , Substitutos Ósseos/química , Sulfato de Cálcio/química , Durapatita/química , Polímeros/química , Crânio/metabolismo , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Regeneração Óssea , Substitutos Ósseos/metabolismo , Teste de Materiais , Polimerização , Porosidade , Próteses e Implantes , Coelhos , Crânio/cirurgia
14.
J Biomater Sci Polym Ed ; 29(16): 1994-2010, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30474514

RESUMO

The novel Ca-zeolite/poly(amino acid) (CaY/PAA) composites for bone substitute applications with hemostatic activity were prepared using the in situ melting polymerization method. In this study, Ca-zeolite (CaY) loaded with Ca2+ was obtained from Y-type zeolite (NaY) by ion-exchange method. The properties of the CaY/PAA composites and PAA, including composition, structure, compressive strength, in vitro degradability in phosphate-buffered solution (PBS), bioactivity, cytocompatibility and in vitro coagulation tests were characterized and investigated. The results showed that compressive strength of the CaY/PAA composites ranged from 145 to 186 MPa, demonstrating sufficient mechanical strength for load-bearing bone substitute. After soaking in PBS for 16 weeks, the weight loss of 25CaY/PAA and 50CaY/PAA were 4.1 and 1.6 wt%, respectively, and the pH values for CaY/PAA composites increased to about 8.0 in 2 weeks and then gradually stabilized around 7.4, indicating good stability in PBS. Scanning electron microscope and energy dispersive spectrometer results showed that the composites were bioactive and new apatite layers attached on their surfaces. Mesenchymal stem cells (MSCs) exhibited high-proliferation in the extract solution of the CaY/PAA composites and were well spread on the surfaces of the composites. Cells on the CaY/PAA composite groups showed higher alkaline phosphatase (ALP) activity indicating the potential to promote cell differentiation. The in vitro coagulation tests showed that CaY/PAA composites have shorter clotting time and better performance of promoting blood coagulation than other samples, presenting improved hemostatic activity. In summary, the results demonstrated that the CaY/PAA composites had good mechanical strength, stability, bioactivity, cytocompatibility and hemostatic activity for bone substitute applications.


Assuntos
Aminoácidos/química , Substitutos Ósseos/química , Cálcio/química , Hemostáticos/química , Polímeros/química , Zeolitas/química , Animais , Materiais Biocompatíveis/química , Adesão Celular/efeitos dos fármacos , Diferenciação Celular , Proliferação de Células/efeitos dos fármacos , Força Compressiva , Células-Tronco Mesenquimais/citologia , Camundongos , Propriedades de Superfície , Engenharia Tecidual , Alicerces Teciduais/química
15.
Brain Behav ; 8(11): e01132, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30264518

RESUMO

INTRODUCTION: Therapeutic effects of repetitive transcranial magnetic stimulation (rTMS) on motor recovery of Parkinson's disease (PD) have been reported; however, the protocols of these studies varied greatly. The aim of this meta-analysis was to evaluate the optimal rTMS parameters for motor recovery of PD. METHODS: Electronic databases were searched for studies investigating the therapeutic effects of rTMS on motor function in patients with PD. The section III of the Unified Parkinson's Disease Rating Scale (UPDRS) was extracted as the primary outcome, and the standardized mean difference (SMD) with 95% confidence interval (CI) was calculated. RESULTS: Twenty-three studies with a total of 646 participants were included. The pooled estimates of rTMS revealed significant short-term (SMD, 0.37; p < 0.00001) and long-term (SMD, 0.39; p = 0.005) effects on motor function improvement of PD. Subgroup analysis observed that high-frequency rTMS (HF-rTMS) was significant in improving motor function (SMD, 0.48; p < 0.00001), but low-frequency rTMS (LF-rTMS) was not. In particular, when HF-rTMS targeted over the primary motor cortex (M1), in which the bilateral M1 revealed a larger effect size than unilateral M1. Compared to single-session, multi-session of HF-rTMS over the M1 showed significant effect size. In addition, HF-rTMS over the M1 with a total of 18,000-20,000 stimulation pulses yielded more significant effects (SMD, 0.97; p = 0.01) than other dosages. CONCLUSIONS: In conclusion, multi-session of HF-rTMS over the M1 (especially bilateral M1) with a total of 18,000-20,000 pulses appears to be the optimal parameters for motor improvement of PD.


Assuntos
Doença de Parkinson/terapia , Estimulação Magnética Transcraniana/métodos , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiologia , Doença de Parkinson/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Estimulação Magnética Transcraniana/efeitos adversos
16.
Int J Clin Exp Pathol ; 11(9): 4552-4561, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31949853

RESUMO

Aberrant activation of Wnt/ß-catenin signaling is one of the most frequent abnormalities in human cancer, including breast cancer. The prognostic value of Wnt ligands has never been fully characterized. In this study, we focused on four Wnt ligands, namely Wnt1, Wnt7a, Wnt7b and Wnt9a, which were commonly studied and found pivotal in Wnt/ß-catenin signaling, but seldom explored for their prognostic value. We investigated the expression of Wnt1, Wnt7a, Wnt7b and Wnt9a in breast cancer tissues by using real-time PCR and immunohistochemical analysis, and further identified their prognostic significance. Results demonstrated that only Wnt7b expression level in breast cancer was significantly higher than that of benign breast. Spearman rank-correlation analysis revealed the expression level of Wnt1, Wnt7b and Wnt9a, but not Wnt7a, were all significantly associated with positive lymph nodes. The Kaplan-Meier survival curve demonstrated that patients with high Wnt7b expression had a shorter overall survival (OS) and recurrence-free survival (RFS) than those with low Wnt7b expression. Moreover, the univariate and multivariate analysis revealed that Wnt7b expression was an independent prognostic factor for both OS and RFS of breast cancer patients. In addition, the high expression of Wnt7b in breast cancer and its prognostic role were further validated by GENT (Gene Expression database of Normal and Tumor tissues) database and the Kaplan-Meier plotter database. Taken together, we identified that high expression of Wnt7b, rather than Wnt1, Wnt7a and Wnt9a, may serve as a prognostic biomarker for breast cancer.

17.
Front Psychiatry ; 9: 769, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30761029

RESUMO

Objective: The purpose of this meta-analysis was to investigate the antidepressant effects of repetitive transcranial magnetic stimulation (rTMS) over the prefrontal cortex (PFC) of patients with Parkinson's disease (PD) and to determine the optimal rTMS parameters, such as the intensity, frequency and the delivered pattern of rTMS stimulation. Methods: EMBASE, PubMed, Web of Science, MEDLINE, and Cochrane data bases were researched for papers published before March 12, 2018. Studies investigating the anti-depression effects of rTMS over PFC in patients with PD were considered. The main outcomes of pre- and post-rTMS treatment as well as score changes were all extracted. The mean effect size was estimated by calculating the standardized mean difference (SMD) with 95% confidence interval (CI) by using fixed or random effect models as appropriate. Results: Nine studies containing 137 PD patients with depression were included. The pooled results showed significant pre-post anti-depressive effects of rTMS over PFC in PD patients with depression (SMD = -0.80, P < 0.00001). The subgroup analyses of stimulation intensity, frequencies, and models also revealed significant effects (Intensities: 90% RMT: SMD = -1.16, P = 0.0006; >100% RMT: SMD = -0.82, P < 0.0001. Frequencies: < 1.0 Hz: SMD = -0.83, P = 0.03; 5.0 Hz: SMD = -1.10, P < 0.0001; ≥10.0 Hz: SMD = -0.55, P = 0.02. Models: Continuous: SMD = -0.79, P < 0.0001; Discontinuous: SMD = -0.84, P = 0.02). But the results of the studies with place-controlled designs were not significant (Overall: SMD = -0.27, P = 0.54. Intensities: 90% RMT: SMD = 0.27, P = 0.68; 100% RMT: SMD = -0.32, P = 0.33. Frequencies: 5.0 Hz: SMD = -0.87, P = 0.10; ≥10.0 Hz: SMD = 0.27, P = 0.66. Models: Continuous: SMD = -0.28, P = 0.68; Discontinuous: SMD = -0.32, P = 0.33). The greater effect sizes of rTMS with 90% RMT, 5.0 Hz in discontinuous days can be observed rather than the other parameters in both kinds of analyses across study design. Conclusions: rTMS may have a significant positive pre-post anti-depressive effect over PFC on patients with depression, especially by using 5.0 Hz frequency with 90% RMT intensity in discontinuous days, which may produce better effects than other parameters. The real effect, though, was not different from that of the placebo. Future studies with larger sample sizes and high-quality studies are needed to further corroborate our results and to identify the optimal rTMS protocols.

18.
J Biomater Sci Polym Ed ; 28(18): 2154-2170, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28950766

RESUMO

Owing to the good degradability and biocompatibility of polyphosphoesters (PPEs), the aim of the current study was to investigate a novel degradable composite of nano-hydroxyapatite/poly(amino acid) (n-HA/PAA) with cyclophosphate (CPE) via in situ melting polymerization to improve the degradation of n-HA/PAA. The structure of each composite was characterized via Fourier transform infrared spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The degradation properties were studied in terms of the weight loss and pH in a phosphate-buffered saline (PBS) solution, while the surface morphology was examined using a scanning electron microscope-energy dispersive spectrometer (SEM-EDS) after soaking the surface in simulated body fluid (SBF). The cell proliferation, cell adhesion, and alkaline phosphatase (ALP) activity were used for the analysis of cytocompatibility. The weight loss results showed that the n-HA/PAA composite was 9.98 wt%, weighed after soaking in the PBS solution for 12 weeks, whereas the nano-hydroxyapatite/polyphosphoester-amino acid (n-HA/PPE-AA) composite was 46.94 wt%. The pH of the composites was in a suitable range between 6.64 to 7.06 and finally stabilized at 7.39. The SEM and EDS results revealed the formation of an apatite-like layer on the surface of the n-HA/PPE-AA composites after soaking in SBF for one week. The cell counting Kit 8 (CCK-8) assay of the cell culture in the leaching liquid of the n-HA/PPE-AA composites exhibited non-cytotoxicity and high-proliferation, and the cell adhesion showed the well spreading and normal phenotype extension of the cells on the n-HA/PPE-AA composites surface. Concurrently, the co-culture results of the composites and cells confirmed that the n-HA/PPE-AA composites exhibited a higher ALP activity. In summary, the results demonstrated that the n-HA/PPE-AA composites had a controllable degradation property, good bioactivity, and cytocompatibility.


Assuntos
Aminoácidos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Durapatita/química , Nanoestruturas/química , Fosfatos/química , Fosfatase Alcalina/metabolismo , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos
19.
J Exp Clin Cancer Res ; 36(1): 92, 2017 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-28697793

RESUMO

BACKGROUND: Collagen triple helix repeat containing-1 (CTHRC1), which was firstly identified overexpressed in the adventitia and neointima of injured rat arteries, could inhibit collagen expression and increase cell migration. It was then found to be ubiquitously expressed in numerous cell types such as fibroblasts and smooth muscle cells, and aberrantly up-regulated in several malignant tumors. However, the functional role of CTHRC1 and its related mechanism in breast cancer still remains unclear. METHODS: CTHRC1 expressions in breast cancer tissues and cells were assessed by qRT-PCR, western blot and immunohistochemistry. The relative expression level of miR-134, miR-155, miR-30c and miR-630 in breast cancer cells respectively was detected by qRT-PCR. Wild type (Wt) and Mutant type (Mut) CTHRC1 3'UTR sequences were cloned into a psi-CHECK2 reporter vector, and the relative luciferase activity was detected by dual-luciferase reporter assay in indicated cells. The effect of ectopic expression of miR-30c or gain and loss of CTHRC1 on cell viability, cell proliferation, cell cycle progression and apoptosis, cell invasion and migration was respectively detected by CCK-8 assay, colony formation assay, flow cytometry analysis, transwell invasion/migration assay. Protein levels of ß-catenin, active ß-catenin, normal and phosphorylated form of GSK-3ß were detected by western blot in indicated cells. Immunofluorescence staining of ß-catenin was performed to observe nuclear localization. RESULTS: We found CTHRC1 was frequently up-regulated in human breast cancer cells and tissues. Then our cohort study and further meta-analysis validated high expression of CTHRC1 was associated with aggressive clinicopathological features and poor clinical outcome of breast cancer patients. In addition, CTHRC1 promoted cell proliferation, invasion and migration and suppressed cell apoptosis in breast cancer, which might be by activating GSK-3ß/ß-catenin signaling and inhibiting Bax/Caspase-9/Caspase-3 signaling respectively; and these biological functions of CTHRC1 could be directly negatively regulated by miR-30c. CONCLUSION: Taken together, we identified the role of miR-30c/CTHRC1 axis in breast cancer progression and demonstrated CTHRC1 may serve as a prognostic biomarker and therapeutic target for breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas da Matriz Extracelular/genética , MicroRNAs/genética , Adulto , Idoso , Apoptose/genética , Biomarcadores , Biomarcadores Tumorais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Razão de Chances , Prognóstico , Interferência de RNA , Transdução de Sinais , Carga Tumoral
20.
Int J Clin Exp Pathol ; 10(11): 10852-10862, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31966428

RESUMO

Glyoxalase 1 (Glo1) is an enzyme that plays a role to metabolize and inactivate methylglyoxal. Previous studies also have confirmed that Glo1 is closely related with tumorigenesis, metastasis, and drug-resistant, but its prognostic value in breast cancer has never been explored. In this study, we investigated the expression of Glo1 in breast cancer cell lines and tissues using real-time PCR, western blot and immunohistochemical analysis. We found Glo1 was frequently up-regulated in human breast cancer cells and tissues, and high expression of Glo1 was associated with positive lymph node, lymphovascular invasion, and TNM stage (all P<0.05). The Kaplan-Meier survival curve demonstrated that patients with high Glo1 expression had a shorter overall survival (OS) and recurrence-free survival (RFS) (Both P<0.001) than those with low Glo1 expression. Moreover, the univariate and further multivariate analysis revealed that Glo1 expression was an independent prognostic factor for both OS and RFS of breast cancer patients. Next, with CCK-8 assay, cell apoptosis analysis, colony formation assay, transwell invasion/migration assay, and wound-healing assay, we validated knock-down of Glo1 suppressed invasion and migration and promoted apoptosis of breast cancer cells. Taken together, we demonstrated the tumor-promoter Glo1 may serve as a prognostic biomarker for breast cancer.

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