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1.
Adv Healthc Mater ; : e1901761, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31999081

RESUMO

Over the past two decades, electrospun nanofibers have been actively explored for a range of applications, including those related to biomedicine, environmental science, energy harvesting, catalysis, photonics, and electronics. Regarding biomedical applications, one can readily produce nanofiber-based scaffolds with controlled compositions, structures, alignments, and functions by varying the material, design of collector, number of spinnerets, and electrospinning parameters. This report highlights both preclinical and translational applications of electrospun nanofibers and bioprinted constructs presented at the 2019 International Conference on Electrospinning, together with some perspectives on their future development.

2.
Int J Biol Macromol ; 147: 653-666, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31923505

RESUMO

In this study, a novel injectable hydrogel with biocompatibility and biodegradability through Schiff base reaction was prepared for soft tissue adhesive and hemostasis. Aldehyde hydroxyethyl starch (AHES) was prepared by oxidizing hydroxyethyl starch to get aldehyde groups. Amino carboxymethyl chitosan (ACC) was prepared by grafting ethylenediamine onto carboxymethyl chitosan to get more amino groups. Two-component AHES/ACC hydrogel was formed through Schiff base reaction between aldehyde and amino groups. By changing the reaction conditions various contents of aldehyde and amino group were achieved. The properties of AHES/ACC hydrogel were tunable including gelation time, swelling ratio, degradation and mechanical tensile by varying the content of aldehyde and amino groups. Then biocompatibility measurements showed that AHES/ACC hydrogels supported cell viability and proliferation in vitro and exhibited good biodegradability and biocompatibility in vivo. AHES/ACC hydrogel also had effective hemostatic ability. Thus, this study provides a strategy for the design and fabrication of fast in situ forming hydrogels. Through Schiff base reaction in situ forming hydrogel derived from natural polysaccharides can be modulated and prepared for soft tissue adhesive, hemostasis or other biomedical applications in future.

3.
ACS Appl Mater Interfaces ; 12(2): 2023-2038, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31895528

RESUMO

In the management of accelerating wound healing, moist environments play an important role. Compared with other scaffolds of various forms, hydrogels can maintain a moist environment in the wound area. They are cross-linked hydrophilic polymeric networks that resemble natural soft tissues and extracellular matrices. Among them, injectable hydrogels have attracted great attention in wound repair, as they can be injected into irregular-shaped skin defects and formed in situ to shape the contour of different dimensions. The excellent compliance makes hydrogels easy to adapt to the wound under different conditions of skin movement. Here, we oxidized hydroxyethyl starch (O-HES) and modified carboxymethyl chitosan (M-CMCS) to fabricate an in situ forming hydrogel with excellent self-recoverable extensibility-compressibility, biocompatibility, biodegradability, and transparency for accelerating wound healing. The oxidation degree of O-HES was 74%. The amino modification degree of M-CMCS was 63%. M-CMCS/O-HES hydrogels were formed through the Schiff base reaction. The physicochemical properties of M-CMCS/O-HES hydrogels with various ratios were investigated, and M-CMCS/O-HES hydrogel with a volume ratio of 5:5 exhibited appropriate gelation time, notable water-retaining capacity, self-recoverable conformal deformation, suitable biodegradability, and good biocompatibility for wound-healing application. Then, skin wound-healing experimental studies were carried out in Sprague-Dawley rats with full-thickness skin defects. Significant outcomes were achieved in the M-CMCS/O-HES hydrogel-treated group including higher wound closure percentage, more granulation tissue formation, faster epithelialization, and decreased collagen deposition. These findings demonstrate that using the obtained M-CMCS/O-HES hydrogels is a promising therapeutic strategy for wound healing.

4.
Eur J Pharmacol ; 868: 172881, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31866405

RESUMO

Psoriasis is a chronic, inflammatory skin disease with high incidence and high rates of relapse, for which no satisfactory treatments are currently available. Yes-associated protein (YAP) is highly expressed in psoriasis and may regulate the proliferation and apoptosis of keratinocytes. Danshen is a traditional Chinese medicine, commonly used in the treatment of psoriasis. Danshensu is the most abundant water-soluble component of Danshen, but its therapeutic mechanism is still unclear. In this study, MTT was used to detect the effects of different danshensu concentrations (0.125, 0.25, 0.5 mmol/l) on the proliferation of an M5-based psoriasis cell model. The effects of danshensu on cell cycle and apoptosis were detected by flow cytometry. Cyclins and apoptosis-related proteins were evaluated by Western blot. Danshensu (20, 40, 80 mg/kg/day) was administered intraperitoneally to the imiquimod (IMQ) psoriasis mouse model. After 7 days, the expression of YAP in the lesions was detected by immunohistochemistry and Western blot. We found that danshensu reduced the expression of YAP in the M5 psoriasis cell model, inhibited cell proliferation, induced cell cycle arrest in G0/G1 phase, and promoted cell apoptosis. All these effects were partly reverted by YAP overexpression. The skin lesions of IMQ mice were thinned and the scales reduced after intragastric administration of danshensu, which also resulted in dose-dependent inhibition of YAP expression. We concluded that danshensu prevents abnormal epidermis proliferation in psoriasis possibly by modulating YAP expression. Our work can provide a theoretical basis for the clinical application of Danshen in the treatment of psoriasis.

5.
Front Pharmacol ; 10: 1275, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31736756

RESUMO

Angiogenesis involves the activation of endothelial cells followed by capillary formation. Leptin, the protein product of the ob gene, can induce the angiogenic potential of endothelial cells. However, the underlying cellular mechanism still remains to be elicited. We firstly evaluated the in vitro effects of leptin on proliferation and angiogenic differentiation of endothelial cell line EA.hy926. Leptin was found to potently induced cell proliferation, expression of angiogenic gene, migration and tube formation. Then we investigated the roles of the Akt and Wnt signaling pathways in the aforementioned processes. It showed that Akt and Wnt signaling pathways could be activated by leptin, while inhibition of the Akt and Wnt signaling pathways by siRNAs effectively blocked the leptin-induced angiogenesis. Finally, we used electrospinning to fabricated leptin-immobilized linear poly(L-lactide-co-caprolactone) (PLCL)-leptin. The in vivo vessel formation of PLCL-leptin was evaluated using subcutaneous implants in Sprague-Dawley rats. The histological and immunofluorescence revealed that cell infiltration with PLCL-leptin was much more significant than that with the control PLCL group. More importantly, the number of laminin+ vessels and CD31+ cells in PLCL-leptin grafts was significantly higher than in control grafts. The study demonstrated that it is via Akt and Wnt signaling pathways that leptin promotes the proliferation and angiogenic differentiation of endothelial cells and the capacity of endogenous tissue regeneration makes the novel leptin-conjugated PLCL promising materials for grafts.

6.
Mol Med Rep ; 20(5): 4645-4653, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31545496

RESUMO

Previous studies have demonstrated that microRNA (miR)­146a is involved in the inflammatory response of atopic dermatitis (AD). The aim of the present study was to investigate the expression of miR­146a in the serum of patients with AD and in skin lesions of AD animal models. In addition, we aimed to predict and verify the target genes of miR­146a. miR­146a expression was measured in AD patient serum via reverse transcription­quantitative PCR. T­helper (Th)1 [CD4+; interferon (IFN)­Î³+] and Th2 [CD4+; interleukin (IL)­4+] expression in peripheral blood mononuclear cells was evaluated using flow cytometry. Following the establishment of a 2,4­dinitrofluorobenzene­induced C57BL/6 mouse AD model, Th1 (CD4+IFN­Î³+) and Th2 (CD4+IL­4+) expression was analyzed in murine spleen cells via flow cytometry. Plasmids were transfected into 293T cells and at 48 h post­transfection, cells were analyzed using a luciferase assay system. The results revealed that the AD group had a significantly lower Th1/Th2 ratio and a significantly higher miR­146a expression compared with the control group (P<0.05). Furthermore, a decreased Th1/Th2 ratio and a significantly increased miR­146a expression were observed in the model group compared with the control group (P<0.01). We also conducted a dual­luciferase assay to determine whether small ubiquitin­related modifier 1 (SUMO1) if the target gene of miR­146a. We observed a ~30% decrease in the relative luciferase activity in cells containing the 3'­untranslated region of SUMO1 + miR­146a). The results of the luciferase assay indicated that may be a direct mRNA target of miR­146a; however, the quantification of band density of SUMO1 expression following western blotting did not significantly differ. The development of animal models in AD research is of vital importance. The results revealed that miR­146a may be a potential regulator involved in the pathogenesis of AD. Furthermore, the current study determined that miR­146a could be a valuable marker of AD and thus, may be applied in the development of therapeutic strategies for treating AD.

7.
Iran J Allergy Asthma Immunol ; 18(4): 347-357, 2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31522443

RESUMO

Atopic dermatitis (AD) is a chronic, recurrent skin condition resulting from both genetic and environmental factors. In recent decades, the prevalence of AD has increased considerably in some countries. However, given that the role of genetics is unlikely to have changed over this short period, the increased prevalence is more likely to be explained by changes in environmental and maternal factors. The aim of this review is to comprehensively summarize the various factors impacting AD incidence in offspring and provide guidance for primary prevention. Recent research has demonstrated that environmental and climate factors, maternal history of allergies, gestational diabetes, and stress play essential roles in increasing the risk of AD in infants. Some factors have protective effects against the incidence of AD, including probiotic supplementation, fish intake, and moisturizers. This review also considers fundamental research into AD prevalence and factors that in the past were mistakenly thought to affect that prevalence, such as caesarean section and antigen avoidance. The potential influence of these factors on infant AD incidence remains inconclusive and needs further study. Furthermore, infants with a family history of atopic disease may benefit from early weaning or reduced breastfeeding duration.

8.
Nanomedicine (Lond) ; 14(18): 2395-2408, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31456475

RESUMO

Aim: Multidrug resistance is the main reason for the failure of chemotherapy during the treatment of the tumor. To overcome multidrug resistance, this study attempts to develop a novel transdermal drug-delivery system (TDDS) loading cytotoxic drug and chemosensitizer. Materials & methods: The polyethylenimine-modified ethosomes (Eth-PEI) and sodium cholate-modified ethosomes (Eth-SC) were firstly fabricated, and then a novel TDDS based on the carriers complex of Eth-PEI/Eth-SC was prepared by electrostatic interaction and evaluated both in vitro and in vivo. Results: The Eth-PEI/Eth-SC showed the excellent antitumor effect on treating melanoma, using doxorubicin and curcumin as the cytotoxic drug and chemosensitizer, respectively. Conclusion: The as-prepared TDDS composed of Eth-PEI/Eth-SC loading multidrug is an effective means for treating melanoma.

9.
Angew Chem Int Ed Engl ; 58(46): 16416-16421, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373102

RESUMO

We report a simple method for the photothermal welding of nonwoven mats of electrospun nanofibers by introducing a near-infrared (NIR) dye such as indocyanine green. By leveraging the strong photothermal effect of the dye, the nanofibers can be readily welded at their cross points or even over-welded (i.e., melted and/or fused together) to transform the porous mat into a solid film upon exposure to a NIR laser. While welding at the cross points greatly improves the mechanical strength of a nonwoven mat of nanofibers, melting and fusion of the nanofibers can be employed to fabricate a novel class of photothermal papers for laser writing or printing without chemicals or toner particles. By using a photomask, we can integrate photothermal welding with the gas foaming technique to pattern and then expand nonwoven mats into 3D scaffolds with well-defined structures. This method can be applied to different combinations of polymers and dyes, if they can be co-dissolved in a suitable solvent for electrospinning.

10.
Pharmaceutics ; 11(8)2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31382396

RESUMO

Essential oils are complex volatile compounds, extracted from specific plant species, with promising therapeutic potentials. However, their volatile nature presents a major hindrance in using them as therapeutic agents. In the current study, we successfully encapsulated oregano essential oil (OEO) into Poly (l-lactic acid-co-e-caprolactone) /Silk Fibroin (PLCL/SF) polymers through electrospinning. The nanofibrous membrane (NF) was fabricated and characterized for various physico-chemical and biological attributions. Homogenous and bead free morphology was confirmed by scanning electron microscopy (SEM). Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) confirmed the successful loading of OEO and its physical interaction with the blend of PLCL/SF. Moreover, thermogravimetric analysis (TGA) also confirmed the successful loading and thermostability of the OEO. Although a significant change was noted in tensile strength due to the loading of OEO, the mechanical behaviour still falls into the acceptable ranges required for skin tissue engineering. Similarly, fabricated material was evaluated for its biological significance. Liquid chromatography-mass spectrometry (LC-MS) was employed to determine the release behaviour of OEO from electrospun membranes. LC-MS data, noted for 48 h, confirmed the biphasic release of OEO. Furthermore, NF membranes have shown strong antioxidant and anti-tumor activities. This material is promising and can be implanted to avoid the recurrence of the tumor after its surgical removal.

11.
Int J Nanomedicine ; 14: 4261-4276, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31289441

RESUMO

Purpose: In the field of small-caliber vascular scaffold research, excellent vascular remodeling is the key to ensuring anticoagulant function. We prepared an off-the-shelf bi-layered vascular scaffold with a dense inner layer and a loose outer layer and evaluated its remodeling capabilities by in vivo transplantation. Materials and Methods: Based on poly(L-lactide-co-ε-caprolactone) (PLCL), silk fibroin(SF), and heparin (Hep), PLCL/SF/Hep bi-layered scaffolds and PLCL/Hep bi-layered scaffolds were prepared by electrospinning. The inner layer was a PLCL/SF/Hep or PLCL/Hep nanofiber membrane, and the outer layer was PLCL/SF nano yarn. The in vitro tests included a hydrophilicity test, mechanical properties test, and blood and cell compatibility evaluation. The in vivo evaluation was conducted via single rabbit carotid artery replacement and subsequent examinations, including ultrasound imaging, immunoglobulin assays, and tissue section staining. Results: Compared to the PLCL/Hep nanofiber membrane, the hydrophilicity of the PLCL/SF/Hep nanofiber membrane was significantly improved. The mechanical strength met application requirements. Both the blood and cell compatibility were optimal. Most importantly, the PLCL/SF/Hep scaffolds maintained lumen patency for 3 months after carotid artery transplantation in live rabbits. At the same time, CD31 and α-SMA immunofluorescence staining confirmed bionic endothelial and smooth muscle layers remodeling. Conclusion: Using this hybrid strategy, PLCL and SF were combined to manufacture bi-layered small-caliber vascular scaffolds; these PLCL/SF/Hep scaffolds showed satisfactory vascular remodeling.


Assuntos
Fibroínas/química , Heparina/farmacocinética , Poliésteres/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Artérias Carótidas , Proliferação de Células , Liberação Controlada de Fármacos , Heparina/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Nanofibras/química , Adesividade Plaquetária , Próteses e Implantes , Coelhos
12.
J Biomed Nanotechnol ; 15(3): 507-517, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31165696

RESUMO

Although different kinds of antibacterial formulas have been explored against bacterial infections, the development of both biocompatible and efficiently antibacterial matrices is still a challenge. In this study, we report a novel HPRP-A2 antimicrobial peptide/silk fibroin (SF) composite nanofibrous matrix fabricated by an all-aqueous electrospinning process (HPRP-A2 is an antibacterial peptide originated from Helicobacter pylori). The HPRP-A2/SF composite nanofibers had a round and smooth morphology. The incorporation of HPRP-A2 had little influence on both the morphology and biocompatibility of the SF nanofibers. Interestingly, the composite nanofibrous matrices showed an impressive antimicrobial activity against both Gram-positive and Gram-negative bacteria. Furthermore, the HPRP-A2/SF composite nanofibers showed excellent performance on accelerating healing of wound according to the data of animal experiment. Considering the facile and all-aqueous process, the HPRP-A2/SF composite nanofibrous matrices could be a promising candidate for antibacterial or wound management applications.


Assuntos
Helicobacter pylori , Nanofibras , Animais , Antibacterianos , Bandagens , Fibroínas , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Peptídeos , Proteínas Ribossômicas
13.
BMC Infect Dis ; 19(1): 506, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182059

RESUMO

BACKGROUND: Scalp mycosis is often caused by dermatophytes and was so called tinea capitis. There is no published report caused by Aspergillus protuberus. We report a rare case of kerion-type scalp mycosis caused by A. protuberus. CASE PRESENTATION: A 5-year-old girl developed pyogenic mass with pain for 8 days and got a fever for 2 days prior to admission. Surgical incision and drainage of the mass, intravenous cefuroxime and metronidazole in the local hospital aggravated the skin lesions. Species identification was performed by observation of morphologic and biochemical characteristicsand sequencing of the internal transcribed spacer (ITS) and ß-tubulin (BT2). Treatment with oral and topical antifungal agents was effective with no relapse during the six months of clinical follow-up. CONCLUSIONS: Aspergillusis a opportunistic pathogenic fungus and its infection occurs mostly in patients with underlying conditions and immunocompromised statuses. So far no report of kerion-type scalp infection has been reported. The first case of kerion-type scalp mycosis caused by A. protuberus was described to highlight the importance of mycological examination that helps to recognize rare pathogenic fungi. Any boggy lesion with hair loss over the scalp and non-responsive to antibiotics should be suspected as resulting from fungal infection, and mycological examination should be performed, especially in children.


Assuntos
Aspergillus/isolamento & purificação , Micoses/diagnóstico , Couro Cabeludo/patologia , Antifúngicos/uso terapêutico , Aspergillus/classificação , Pré-Escolar , Feminino , Humanos , Hospedeiro Imunocomprometido , Micoses/tratamento farmacológico , Micoses/microbiologia , Filogenia , Couro Cabeludo/microbiologia
14.
J Biomed Nanotechnol ; 15(6): 1267-1279, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31072434

RESUMO

An ideal wound dressing should not only promote rapid hemostasis and wound healing but also have good biocompatibility, antimicrobial activities, and should mimic the skin's physiological function. In the present study, five O-quaternized chitosan (QAS-CS) materials with satisfactory antibacterial activity and no cytotoxicity were successfully synthesized. Furthermore, we reported the synthesis and characterization of the two novel composite nanofibrous scaffolds consisting of selfdeveloped collagen (COL), quaternary ammonium salt (QAS) or QAS-CS and polycaprolactone (PCL) or polyvinyl alcohol (PVA) with an electrospinning approach. The PCL/COL/QAS (PCQ3) and PVA/COL/QAS-CS (PCQC5) materials exhibited uniform, three-dimensional interconnected pore structure, high porosity, and large specific surface area, which can mimic the architecture and biological functions of the native extracellular matrix microenvironment and provide suitable conditions for cell adhesion, proliferation, and differentiation. The growth and proliferation of human immortalized epidermal (HaCaT) cells on PCQ3 and PCQC5 materials was good, and the result of blood compatibility and the skin irritant test indicated that the scaffolds had good blood compatibility and did not exhibit significant irritability. Importantly, PCQ3 and PCQC5 have notable effects on rapid hemostasis, antibacterial activity, and anti-inflammation, promote wound healing, and display other superior benefits in comparison to available products. Overall, PCQ3 and PCQC5 are proposed to be good candidates for skin tissue engineering applications and can be used on different types of wounds.


Assuntos
Hemostáticos , Nanofibras , Antibacterianos , Biomimética , Hemostasia , Humanos , Tecidos Suporte , Cicatrização
15.
Pharmaceutics ; 11(4)2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30991742

RESUMO

Electrospinning technologies have been applied in the field of tissue engineering as materials, with nanoscale-structures and high porosity, can be easily prepared via this method to bio-mimic the natural extracellular matrix (ECM). Tissue engineering aims to fabricate functional biomaterials for the repairment and regeneration of defective tissue. In addition to the structural simulation for accelerating the repair process and achieving a high-quality regeneration, the combination of biomaterials and bioactive molecules is required for an ideal tissue-engineering scaffold. Due to the diversity in materials and method selection for electrospinning, a great flexibility in drug delivery systems can be achieved. Various drugs including antibiotic agents, vitamins, peptides, and proteins can be incorporated into electrospun scaffolds using different electrospinning techniques and drug-loading methods. This is a review of recent research on electrospun nanofibrous scaffolds for tissue-engineering applications, the development of preparation methods, and the delivery of various bioactive molecules. These studies are based on the fabrication of electrospun biomaterials for the repair of blood vessels, nerve tissues, cartilage, bone defects, and the treatment of aneurysms and skin wounds, as well as their applications related to oral mucosa and dental fields. In these studies, due to the optimal selection of drugs and loading methods based on electrospinning, in vitro and in vivo experiments demonstrated that these scaffolds exhibited desirable effects for the repair and treatment of damaged tissue and, thus, have excellent potential for clinical application.

16.
Exp Ther Med ; 17(5): 3989-3998, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30988780

RESUMO

Electrospinning using biocompatible polymer scaffolds, seeded with or without stem cells, is considered a promising technique for producing fibrous scaffolds with therapeutic possibilities for ischemic heart disease. However, no optimal scaffolds for treating ischemic heart disease have been identified thus far. In the present study, it was evaluated whether electrospun silk fibroin (SF)-blended poly(L-lactic acid-co-ε-caprolactone) [P(LLA-CL)] scaffolds that were seeded with cluster of differentiation 117 (c-kit)+ bone marrow (BM) cells may serve a protective role in cardiac remodeling following myocardial infarction (MI). Mechanical characteristics and cytocompatibility were compared between SF/P(LLA-CL) and P(LLA-CL) electrospun nanofibrous scaffolds in vitro. It was observed that MI led to a significant increase of the c-kit+ BM cell subpopulation in mice. Magnetic activated cell sorting was performed to harvest the c-kit+ cell population from the BM of mice following MI. c-kit+ BM cells were seeded on SF/P(LLA-CL) and P(LLA-CL) electrospun nanofibrous scaffolds. Results indicated that SF/P(LLA-CL) electrospun nanofibrous scaffolds were superior to P(LLA-CL) electrospun nanofibrous scaffolds in improving c-kit+ BM cell proliferation. Additionally, compared with pure SF/P(LLA-CL) electrospun nanofibrous scaffolds, SF/P(LLA-CL) scaffolds seeded with c-kit+ BM cells resulted in lower levels of MI markers and reduced infarct size, leading to greater global heart function improvement in vivo. The findings of the present study indicated that SF/P(LLA-CL) electrospun nanofibrous scaffolds seeded with c-kit+ BM cells exert a protective effect against MI and may be a promising approach for cardiac regeneration after ischemic heart disease.

17.
J Biomater Appl ; 33(8): 1118-1127, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30665311

RESUMO

Type I collagen, used as a raw material, plays a pivotal role in the development of medical devices and tissue engineering. Due to the risk of zoonotic transmission and religious constraints for mammalian collagen, fish collagen gains increased attention and is widely seen as an alternative. In this study, two collagen micro/nanofiber materials, self-assembled collagen nanofiber and electrospun collagen nanofiber, were prepared by tilapia skin collagen and their biocompatibility and immunogenicity was thoroughly investigated. The result revealed that the state of tilapia skin collagen in self-assembled collagen nanofiber and electrospun collagen nanofiber was different. The circular dichroism spectrum indicated that collagen in self-assembled collagen nanofiber retained the triple helical structure of the native collagen, while collagen in electrospun collagen nanofiber was denatured into gelatin. Nevertheless, the evaluation according to ISO10993, including tests of cytotoxicity, hemolysis, skin sensitization, acute systemic toxicity, mouse immunization and lymphocyte proliferation, demonstrated good biocompatibility and low immunogenicity for both self-assembled and electrospun collagen nanofiber materials. Overall, the present study highlighted that type I collagen from tilapia skin would be a promising biomaterial for the development of regenerate medical products.

18.
J Biomed Nanotechnol ; 15(1): 77-84, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30480516

RESUMO

In this study, we prepared a composite vascular graft with two layers. The inner layer, which was comprised of degradable Poly(lactic-co-glycolic acid) (PLGA)/Collagen (PC) nanofibers modified by mesoporous silica nanoparticles (MSN), was grafted with polyethylene glycol (PEG) and heparin to promote cell proliferation and to improve blood compatibility. The outer layer was comprised of polyurethane (PU) nanofibers in order to provide mechanical support. The growth and proliferation of human umbilical vein endothelial cells (HUVECs) in the inner layer was significant, and blood compatibility testing showed that the inner layer had good blood compatibility. The MSN-PEG-Heparin on the fiber surface was observed in vitro during the degradation of the inner layer. After 60 days, the weight of fiber membrane decreased by 92.4%. The inner layer did not cause an inflammatory reaction during the degradation process in vivo and there was uniform cellular growth on the PC/MSN-PEG-Heparin fiber membrane. Composite grafts implanted into the rabbit carotid artery were evaluated for 8 weeks by H&E and immunohistochemical staining, demonstrating that a monolayer of endothelium (CD31-labeled) and smooth muscle (αSMA-labeled) regenerated on the composite graft. Our results demonstrate that the composite graft, with a functional inner layer, has potential to be used for small-caliber blood vessels with long-term patency.


Assuntos
Nanofibras , Polietilenoglicóis/química , Animais , Prótese Vascular , Heparina , Humanos , Poliuretanos , Coelhos
19.
Acta Biomater ; 84: 98-113, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30471474

RESUMO

Graphene, as a promising biomaterial, has received great attention in biomedical fields due to its intriguing properties, especially the conductivity and biocompatibility. Given limited studies on the effects of graphene-based scaffolds on peripheral nerve regeneration in vitro and in vivo under electrical stimulation (ES), the present study was intended to systematically investigate how conductive graphene-based nanofibrous scaffolds regulate Schwann cell (SC) behavior including migration, proliferation and myelination, and PC12 cell differentiation in vitro via ES, and whether these conductive scaffolds could guide SC migration and promote nerve regeneration in vivo. Briefly, the reduced graphene oxide (RGO) was coated onto ApF/PLCL nanofibrous scaffolds via in situ redox reaction of the graphene oxide (GO). In vitro, RGO-coated ApF/PLCL (AP/RGO) scaffolds significantly enhanced SC migration, proliferation, and myelination including myelin-specific gene expression and neurotrophic factor secretion. The conditioned media of SCs cultured on AP/RGO scaffolds under ES could induce the differentiation of PC12 cells in a separate culture. In addition, PC12 cells cultured on the conductive AP/RGO scaffolds also showed elevated differentiation upon ES. In vivo implantation of the conductive AP/RGO nerve guidance conduits into rat sciatic nerve defects exhibited a similar healing capacity to autograft, which is the current gold standard in peripheral nerve regeneration. In view of the performance of AP/RGO scaffolds in modulating cell functions in vitro and promoting nerve regeneration in vivo, it is expected that the graphene-based conductive nanofibrous scaffolds would exhibit their potential in peripheral nerve repair and regeneration. STATEMENT OF SIGNIFICANCE: Despite the demonstrated capability of bridging the distal and proximal peripheral nerves, it remains a significant challenge with current artificial nerve conduits to achieve the desired physiological functions, e.g., the transmission of electrical stimuli. Herein, we explored the possibility of combining the conductive properties of graphene with electrospun nanofiber to create the electroactive biomimetic scaffolds for nerve tissue regeneration. In vitro and in vivo studies were carried out: (1) In vitro, the conductive nanofibrous scaffolds significantly promoted SC migration, proliferation and myelination including myelin specific gene expression and neurotrophicfactor secretion, and induced PC12 cell differentiation with electrical stimulation. (2) In vivo, the conductive nerve guidance conduit exhibited similar effects with the gold standard autograft. In view of the performance of this conductive scaffold in modulating the cell functions in vitro and promoting nerve regeneration in vivo, it is expected that the graphene-modified nanofibrous scaffolds will exhibit their potential in peripheral nerve repair and regeneration.

20.
J Colloid Interface Sci ; 534: 625-636, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30265990

RESUMO

Tissue scaffolds with three-dimensional (3D) nanofibrous biomimetic structures have attracted attention in the field of bone regeneration. In recent years, emerging strategies based on electrospinning technologies have facilitated the preparation of 3D nanofibrous scaffolds. Based on these developments, in this study, 3D scaffolds possessing both nanofibrous morphologies and interconnected pores were fabricated for their potential in bone tissue engineering. By combining homogenizing, freeze-drying, and thermal crosslinking techniques, nano-hydroxyapatite/PLLA/gelatin (nHA/PLA/GEL) 3D nanofibrous scaffolds were prepared using pre-fabricated electrospun nanofibers. Then, utilizing a polydopamine (pDA)-assisted coating strategy, bone morphogenetic protein-2 (BMP-2)-derived peptides were further immobilized onto the 3D scaffolds to obtain the resulting nano-hydroxyapatite/PLLA/gelatin-peptide (nHA/PLA/GEL-PEP) 3D nanofibrous scaffolds capable of sustained release. Bone mesenchymal stem cells (BMSCs) were cultured on the 3D nanofibrous scaffolds, then relative cell viability, alkaline phosphatase (ALP) activity, and gene expression assays were performed to study the effects of the scaffolds on cell growth and osteogenic differentiation in vitro. Furthermore, the ability of bone formation in vivo was evaluated using a rat cranial bone defect model. In vitro and in vivo results demonstrated that the 3D nanofibrous scaffolds incorporated with nHA and BMP-2 peptides exhibited favorable biocompatibility and osteoinductivity. Therefore, these nanofibrous scaffolds have excellent potential in bone regenerative medicine.


Assuntos
Proteína Morfogenética Óssea 2/química , Regeneração Óssea , Nanofibras/química , Osteogênese , Tecidos Suporte , Animais , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/citologia , Peptídeos/química , Peptídeos/metabolismo , Ratos , Engenharia Tecidual/métodos , Tecidos Suporte/química
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