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1.
J Formos Med Assoc ; 114(1): 17-22, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25618584

RESUMO

BACKGROUND/PURPOSE: Chlorhexidine (CHX) is a type of chemical antiseptic that is widely used in dental practice. Stem cells from human exfoliated deciduous teeth (SHED) are multipotent cells. However, there is little knowledge about the effects of chlorhexidine on SHED cells. The purpose of this study is to investigate the effects of CHX on SHED. METHODS: SHED cells were treated with 0.1%, 0.01%, 0.001%, and 0.0001% CHX for 10 seconds to test the effects of different concentrations of CHX on SHED cells. The cells were also treated with 0.01% CHX for 10 seconds, 1 minute, and 5 minutes to test the time effects of CHX on SHED cells. Cell proliferation was investigated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and an autonomously replicating sequence (ARS) assay was used for the evaluation of the mineralization potential. RESULTS: This study demonstrated that different concentrations of CHX had cytotoxic effects on SHED cells in a dose- and time-dependent manner. The proliferation of SHED cells was inhibited by approximately 50% by the use of 0.01% CHX. It was also found that the cell proliferation and mineralization potential of SHED cells were inhibited to some degree by different concentrations of CHX. CONCLUSION: Different concentrations of CHX can inhibit SHED cell proliferation in a dose- and time-dependent manner. In addition, the mineralization potential of SHED cells is inhibited to some degree by different concentrations of CHX.


Assuntos
Anti-Infecciosos Locais/farmacologia , Proliferação de Células/efeitos dos fármacos , Clorexidina/farmacologia , Células-Tronco/efeitos dos fármacos , Dente Decíduo/citologia , Células Cultivadas , Criança , Polpa Dentária/citologia , Humanos , Taiwan
2.
Prep Biochem Biotechnol ; 44(5): 464-79, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24397718

RESUMO

Distillers' grains are a co-product of ethanol production. In China, only a small portion of distillers' grains have been used to feed the livestock because the amount was so huge. Nowadays, it has been reported that the distillers' grains have the potential for fuel ethanol production because they are composed of lignocelluloses and residual starch. In order to effectively convert distillers' grains to fuel ethanol and other valuable production, sodium hydroxide pretreatment, step-by-step enzymatic hydrolysis, and simultaneous saccharification and fermentation (SSF) were investigated. The residual starch was first recycled from wet distillers' grains (WDG) with glucoamylase to obtain glucose-rich liquid. The total sugar concentration was 21.3 g/L, and 111.9% theoretical starch was hydrolyzed. Then the removed-starch dry distillers' grains (RDDG) were pretreated with NaOH under optimal conditions and the pretreated dry distillers' grains (PDDG) were used for xylanase hydrolysis. The xylose concentration was 19.4 g/L and 68.6% theoretical xylose was hydrolyzed. The cellulose-enriched dry distillers' grains (CDDG) obtained from xylanase hydrolysis were used in SSF for ethanol production. The ethanol concentration was 42.1 g/L and the ethanol productivity was 28.7 g/100 g CDDG. After the experiment, approximately 80.6% of the fermentable sugars in WDG was converted to ethanol.


Assuntos
Grão Comestível/metabolismo , Etanol/metabolismo , Hidróxido de Sódio/metabolismo , Biocombustíveis/análise , Biotecnologia , Endo-1,4-beta-Xilanases/metabolismo , Fermentação , Glucose/metabolismo , Hidrólise , Lignina/metabolismo , Amido/metabolismo , Xilose/metabolismo
3.
Adv Mater ; 36(6): e2307627, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37921269

RESUMO

Protein nanotubes (PNTs) as state-of-the-art nanocarriers are promising for various potential applications both in the food and pharmaceutical industries. Derived from edible starting sources like α-lactalbumin, lysozyme, and ovalbumin, PNTs bear properties of biocompatibility and biodegradability. Their large specific surface area and hydrophobic core facilitate chemical modification and loading of bioactive substances, respectively. Moreover, their enhanced permeability and penetration ability across biological barriers such as intestinal mucus, extracellular matrix, and thrombus clot, make it promising platforms for health-related applications. Most importantly, their simple preparation processes enable large-scale production, supporting applications in the biomedical and nanotechnological fields. Understanding the self-assembly principles is crucial for controlling their morphology, size, and shape, and thus provides the ground to a multitude of applications. Here, the current state-of-the-art of PNTs including their building materials, physicochemical properties, and self-assembly mechanisms are comprehensively reviewed. The advantages and limitations, as well as challenges and prospects for their successful applications in biomaterial and pharmaceutical sectors are then discussed and highlighted. Potential cytotoxicity of PNTs and the need of regulations as critical factors for enabling in vivo applications are also highlighted. In the end, a brief summary and future prospects for PNTs as advanced platforms and delivery systems are included.


Assuntos
Nanotubos , Nanotubos/química , Proteínas , Nanotecnologia , Materiais Biocompatíveis/farmacologia , Sistemas de Liberação de Medicamentos
4.
Sci Total Environ ; 924: 171600, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461986

RESUMO

The electric field-assisted composting system (EACS) is an emerging technology that can enhance composting efficiency, but little attention has been given to electrode materials. Herein, an EACS was established to investigate the effects of electrode materials on humic substance formation and heavy metal speciation. Excitation-emission matrix analysis showed that carbon-felt and stainless-steel electrodes increased humic acid (HA) by 48.57 % and 47.53 %, respectively. In the EACS with the carbon-felt electrode, the bioavailability factors (BF) of Cu and Cr decreased by 18.00 % and 7.61 %, respectively. Despite that the stainless-steel electrodes decreased the BF of As by 11.26 %, the leaching of Cr, Ni, Cu, and Fe from the electrode itself is an inevitable concern. Microbial community analyses indicated that the electric field increased the abundance of Actinobacteria and stimulated the multiplication of heavy metal-tolerant bacteria. Redundancy analysis indicates that OM, pH, and current significantly affect the evolution of heavy metal speciation in the EACS. This study first evaluated the metal leaching risk of stainless-steel electrode, and confirmed that carbon-felt electrode is environment-friendly material with high performance and low risk in future research with EACS.


Assuntos
Compostagem , Metais Pesados , Solo/química , Metais Pesados/análise , Substâncias Húmicas/análise , Aço Inoxidável , Bactérias , Carbono
5.
Mater Today Bio ; 25: 100990, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38371466

RESUMO

Background: Human-treated dentin matrix (hTDM) has recently been studied as a natural extracellular matrix-based biomaterial for dentin pulp regeneration. However, porcine-treated dentin matrix (pTDM) is a potential alternative scaffold due to limited availability. However, there is a dearth of information regarding the protein composition and underlying molecular mechanisms of pTDM.Methods: hTDM and pTDM were fabricated using human and porcine teeth, respectively, and their morphological characteristics were examined using scanning electron microscopy. Stem cells derived from human exfoliated deciduous teeth (SHEDs) were isolated and characterized using flow cytometry and multilineage differentiation assays. SHEDs were cultured in three-dimensional environments with hTDM, pTDM, or biphasic hydroxyapatite/tricalcium phosphate. The expression of odontogenesis markers in SHEDs were assessed using real-time polymerase chain reaction and immunochemical staining. Subsequently, SHEDs/TDM and SHEDs/HA/TCP complexes were transplanted subcutaneously into nude mice. The protein composition of pTDM was analyzed using proteomics and compared to previously published data on hTDM.Results: pTDM and hTDM elicited comparable upregulation of odontogenesis-related genes and proteins in SHEDs. Furthermore, both demonstrated the capacity to stimulate root-related tissue regeneration in vivo. Proteomic analysis revealed the presence of 278 protein groups in pTDM, with collagens being the most abundant. Additionally, pTDM and hTDM shared 58 identical proteins, which may contribute to their similar abilities to induce odontogenesis. Conclusions: Both hTDM and pTDM exhibit comparable capabilities in inducing odontogenesis, potentially owing to their distinctive bioactive molecular networks.

6.
Food Chem Toxicol ; 180: 114002, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37634612

RESUMO

Ubiquitous microplastics have become a threat to animal and human health, due to their potential toxicity, persistent nature and consequent bioaccumulation. Supporting evidence elucidates that polystyrene nanoplastics (PS-NPs) can destroy blood-testis barrier integrity, thus causing testicular hypoplasia and impairment of spermatogenesis. Nevertheless, how PS-NPs modulate macrophage polarization-energy metabolism crosstalk has not been fully investigated in testicular tissue. Here, we observed that polystyrene PS-NPs exposure contributes to severe vacuolization in the seminiferous tubules, accompanied by apoptosis of testicular tissue and infiltration of M1 macrophages. Meanwhile, we found that PS-NPs could trigger the M1 polarization phenotype, which activated ROS-macrophage migration inhibitory factor (MIF)/NF-κB signaling that in turn induced apoptosis of GC2 cells in the GC2-macrophage cell coculture model. Simultaneously, we confirmed that PS-NPs exposure increased 3-phospho-D-glycerate, phosphoenolpyruvate and lactate concentrations, accompanied by decreased pyruvate and adenosine triphosphate (ATP) production, likely due to downregulated pyruvate kinase M2 (PKM2) dimer expression. In conclusion, the mechanism of PS-NPs-induced testicular inflammation can be mediated by promoting the infiltration of M1 macrophages, thereby resulting in an ROS burst and subsequent induction of energy metabolism disorders. The current study will provide new insights into PS-NPs-induced male reproductive toxicity and highlight the context-specific roles of testicular macrophages.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Humanos , Masculino , Microplásticos , Poliestirenos/toxicidade , Plásticos , Espécies Reativas de Oxigênio , Macrófagos , Metabolismo Energético , Inflamação/induzido quimicamente
7.
Mol Metab ; 66: 101617, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36270612

RESUMO

OBJECTIVES: Mesenchymal stromal/stem cell (MSC)-based therapy has become a promising approach to periodontal tissue repair. Adipose-derived stromal/stem cells (ASCs), compared with other dental or non-dental MSCs, serve as promising candidates for MSC therapy due to non-invasive acquisition and abundant sources. This study aimed to explore the effects of ASC therapy in experimental periodontitis and the underlying mechanism. METHODS: Micro-CT was performed to evaluate the alveolar bone parameters following local injection of ASCs. Immunohistochemistry and immunofluorescence were employed to detect the expression of IL-1ß, osteocalcin (OCN), nuclear factor (erythroid-derived 2)-like 2 (NRF2), and surface markers of macrophage polarization. Afterward, multiple reaction monitoring (MRM)-based targeted tryptophan metabolomic analysis was used to examine the ASC metabolites. Chromatin immunoprecipitation (ChIP)-qPCR assay was performed to investigate the direct binding of aryl hydrocarbon receptor (AhR) and NRF2. RESULTS: Alveolar bone loss was reduced, and the ratio of iNOS+/CD206+ macrophages was significantly decreased after ASC injection in the rat models of periodontitis. ASCs promoted NRF2 expression and activation in macrophages, while NRF2 silencing in macrophages blocked the regulation of ASCs on macrophages. Furthermore, the expression of indoleamine 2,3-dioxygenase (IDO) of ASCs in the inflammatory condition was high. The inhibitor of IDO, 1-methyltryptophan (1-MT), impaired the therapeutic effects of ASCs in experimental periodontitis and regulation of macrophage polarization. Mechanistically, kynurenine (Kyn), a metabolite of ASCs catalyzed by IDO, activated AhR and enhanced its binding to the promoter of NRF2, which stimulated M2 macrophage polarization. CONCLUSIONS: These findings suggested that ASCs can alleviate ligature-induced periodontitis through modulating macrophage polarization by the IDO-dependent Kyn-AhR-NRF2 pathway, uncovering a novel mechanism and providing a scientific basis for ASC-based therapy in experimental periodontitis.


Assuntos
Células-Tronco Mesenquimais , Periodontite , Animais , Ratos , Cinurenina/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Fator 2 Relacionado a NF-E2 , Células-Tronco Mesenquimais/metabolismo , Macrófagos/metabolismo , Periodontite/terapia
8.
Stem Cell Res Ther ; 13(1): 234, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35659736

RESUMO

BACKGROUND: Bio-root regeneration is a promising treatment for tooth loss. It has been reported that dental-derived stem cells are effective seed cells for bio-root construction, but further applications are limited by their few sources. Human adipose tissues have a wide range of sources and numerous studies have confirmed the ability of adipose-derived stromal/stem cells (ASCs) in regenerative medicine. In the current study, the odontogenic capacities of ASCs were compared with dental-derived stem cells including dental follicle cells (DFCs), and stem cells from human exfoliated deciduous teeth (SHEDs). METHODS: The biological characteristics of ASCs, DFCs, and SHEDs were explored in vitro. Two-dimensional (2D) and three-dimensional (3D) cultures were compared in vitro. Odontogenic characteristics of porcine-treated dentin matrix (pTDM) induced cells under a 3D microenvironment in vitro were compared. The complexes (cell/pTDM) were transplanted subcutaneously into nude mice to verify regenerative potential. RNA sequencing (RNA-seq) was used to explore molecular mechanisms of different seed cells in bio-root regeneration. RESULTS: 3D culture was more efficient in constructing bio-root complexes. ASCs exhibited good biological characteristics similar to dental-derived stem cells in vitro. Besides, pTDM induced ASCs presented odontogenic ability similar to dental-derived stem cells. Furthermore, 3D cultured ASCs/pTDM complex promoted regeneration of dentin-like, pulp-like, and periodontal fiber-like tissues in vivo. Analysis indicated that PI3K-Akt, VEGF signaling pathways may play key roles in the process of inducing ASCs odontogenic differentiation by pTDM. CONCLUSIONS: ASCs are potential seed cells for pTDM-induced bio-root regeneration, providing a basis for further research and application.


Assuntos
Dentina , Raiz Dentária , Animais , Diferenciação Celular , Polpa Dentária , Dentina/metabolismo , Camundongos , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Células-Tronco , Suínos
9.
J Control Release ; 351: 324-340, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36155206

RESUMO

The intervention effects of delivery systems on the digestion and adsorption profiles and, thus, the pharmacological effects of bioactive compounds represent an intriguing scientific hypothesis that can be proven with research case studies. Delivery systems with tailor-made structures fabricating from the same building materials offer a new research strategy for deciphering the modulating effects of the digestive fate on the therapeutic efficacy of encapsulated bioactive compounds. Herein, we developed capsaicin-loaded core-shell nanoparticles (Cap NPs), microparticles (Cap MPs) and nano-in-micro particles (Cap NPs in MPs) and investigated their regulatory effects on the digestive fate and colitis-alleviating mechanisms of capsaicin. Results suggested that the small intestine dominant absorption of Cap NPs differed significantly with the colorectal dominated accumulation of Cap MPs and Cap NPs in MPs in terms of the colitis alleviating mechanisms. Cap NPs alleviated colitis mainly through promoting the colonization of short-chain fatty acid-producing bacteria, maintaining intestinal barrier homeostasis and partially inhibiting the activation of the NF-κB pro-inflammatory pathway. Whereas, better dietary intervention effects were achieved from Cap NPs in MPs via promoting the proliferation of mucus-related bacteria and enhanced triggering efficiency on the TRPV1-mucus-microbiotas cyclic cascade. This work confirmed that rationally designed biomaterial-based delivery vehicles can flexibly interfere with the therapeutic mechanisms of encapsulated cargos, representing a new horizon in the field of precise nutrition.


Assuntos
Colite , Nanopartículas , Humanos , Capsaicina/uso terapêutico , Capsaicina/química , Nanopartículas/química , Colite/tratamento farmacológico , Materiais Biocompatíveis
10.
Biofabrication ; 14(4)2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-35995036

RESUMO

Electroceuticals provide promising opportunities for peripheral nerve regeneration, in terms of modulating the extensive endogenous tissue repair mechanisms between neural cell body, axons and target muscles. However, great challenges remain to deliver effective and controllable electroceuticals via bioelectronic implantable device. In this review, the modern fabrication methods of bioelectronic conduit for bridging critical nerve gaps after nerve injury are summarized, with regard to conductive materials and core manufacturing process. In addition, to deliver versatile electrical stimulation, the integration of implantable bioelectronic device is discussed, including wireless energy harvesters, actuators and sensors. Moreover, a comprehensive insight of beneficial mechanisms is presented, including up-to-datein vitro, in vivoand clinical evidence. By integrating conductive biomaterials, 3D engineering manufacturing process and bioelectronic platform to deliver versatile electroceuticals, the modern biofabrication enables comprehensive biomimetic therapies for neural tissue engineering and regeneration in the new era.


Assuntos
Regeneração Nervosa , Tecido Nervoso , Materiais Biocompatíveis/farmacologia , Regeneração Nervosa/fisiologia , Nervos Periféricos/fisiologia , Engenharia Tecidual
11.
Cell Prolif ; 54(1): e12957, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33231338

RESUMO

BACKGROUND: Periodontitis is a prevalent oral inflammatory disease, which can cause periodontal ligament to a local hypoxia environment. However, the mechanism of hypoxia associated long non-coding RNAs (lncRNAs) involved in periodontitis is still largely unknown. METHODS: Microarray was performed to detect the expression patterns of lncRNAs in 3 pairs of gingival tissues from patients with periodontitis and healthy controls. The expression of lncRNA 01126 (LINC01126), miR-518a-5p and hypoxia-inducible factor-1α (HIF-1α) in periodontal tissues and in human periodontal ligament cells (hPDLCs) under hypoxia was measured by quantitative real-time polymerase chain reaction or western blot. Fluorescence in situ hybridization and cell fraction assay were performed to determine the subcellular localization of LINC01126 and miR-518a-5p. Overexpression or knockdown of LINC01126 or HIF-1α was used to confirm their biological roles in hPDLCs. MTT assays were performed to evaluate hPDLCs proliferation ability. Flow cytometry was used to detect apoptosis. ELISA was used to measure the expression levels of interleukin (IL)-1ß, IL-6, IL-8 and TNF-α. Dual-luciferase reporter assays were performed to assess the binding of miR-518a-5p to LINC01126 and HIF-1α. RNA immunoprecipitation assay was used to identify whether LINC01126 and miR-518a-5p were significantly enriched in AGO-containing micro-ribonucleoprotein complexes. RESULTS: We selected LINC01126, which was the most highly expressed lncRNA, to further verify its functions in periodontitis-induced hypoxia. The expression of LINC01126 was increased in periodontal tissues. In vitro experiment demonstrated that LINC01126 suppressed proliferation, promoted apoptosis and inflammation of hPDLCs under hypoxia via sponging miR-518a-5p. Moreover, we identified HIF-1α acted as a direct target of miR-518a-5p in hPDLCs and LINC01126 promoted periodontitis pathogenesis by regulating the miR-518a-5p/HIF-1α/MAPK pathway. CONCLUSION: LINC01126 promotes periodontitis pathogenesis of hPDLCs via miR-518a-5p/HIF-1α/MAPK pathway, providing a possible clue for LINC01126-based periodontal therapeutic approaches.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ligamento Periodontal/metabolismo , Periodontite/metabolismo , RNA Longo não Codificante/metabolismo , Adulto , Apoptose , Proliferação de Células , Feminino , Células HEK293 , Humanos , Hibridização in Situ Fluorescente , Masculino , Ligamento Periodontal/patologia , Periodontite/patologia , RNA Longo não Codificante/genética
12.
Nat Biomed Eng ; 5(8): 864-879, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33737730

RESUMO

Muscle loss and impairment resulting from traumatic injury can be alleviated by therapies using muscle stem cells. However, collecting sufficient numbers of autologous myogenic stem cells and expanding them efficiently has been challenging. Here we show that myogenic stem cells (predominantly Pax7+ cells)-which were selectively expanded from readily obtainable dermal fibroblasts or skeletal muscle stem cells using a specific cocktail of small molecules and transplanted into muscle injuries in adult, aged or dystrophic mice-led to functional muscle regeneration in the three animal models. We also show that sustained release of the small-molecule cocktail in situ through polymer nanoparticles led to muscle repair by inducing robust activation and expansion of resident satellite cells. Chemically induced stem cell expansion in vitro and in situ may prove to be advantageous for stem cell therapies that aim to regenerate skeletal muscle and other tissues.


Assuntos
Músculo Esquelético/fisiologia , Regeneração , Células Satélites de Músculo Esquelético/citologia , Animais , Reprogramação Celular/efeitos dos fármacos , Colforsina/farmacologia , Meios de Cultura/química , Meios de Cultura/farmacologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Camundongos , Doenças Musculares/terapia , Nanopartículas/química , Fator de Transcrição PAX7/metabolismo , Polímeros/química , Células Satélites de Músculo Esquelético/metabolismo , Células Satélites de Músculo Esquelético/transplante , Transplante de Células-Tronco , Células-Tronco/citologia , Células-Tronco/metabolismo , Ácido Valproico/farmacologia
13.
Curr Biol ; 17(19): 1708-13, 2007 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-17900903

RESUMO

Perceiving the pain of others activates a large part of the pain matrix in the observer [1]. Because this shared neural representation can lead to empathy or personal distress [2, 3], regulatory mechanisms must operate in people who inflict painful procedures in their practice with patient populations in order to prevent their distress from impairing their ability to be of assistance. In this functional magnetic resonance imaging MRI study, physicians who practice acupuncture were compared to naive participants while observing animated visual stimuli depicting needles being inserted into different body parts, including the mouth region, hands, and feet. Results indicate that the anterior insula somatosensory cortex, periaqueducal gray, and anterior cingulate cortex were significantly activated in the control group, but not in the expert group, who instead showed activation of the medial and superior prefrontal cortices and the temporoparietal junction, involved in emotion regulation and theory of mind.


Assuntos
Acupuntura , Competência Clínica , Empatia , Dor/psicologia , Adulto , Feminino , Humanos , Masculino , Medição da Dor/psicologia , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Lobo Temporal/fisiologia
14.
J Appl Biomater Funct Mater ; 18: 2280800020975172, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33307948

RESUMO

BACKGROUND: Poly Ether Ether Ketone (PEEK) has been considered as a potential alternative material for endosseous dental implants, for its low elastic modulus, biocompatibility, and low cost in customized device manufacture. Hydroxyapatite-incorporation is supposed to improve the poor osseointegration of PEEK. METHODS: In the present study we analyzed the in vivo response of hydroxyapatite-incorporated PEEK (PEEK-HA) implants in canine tibia. PEEK-HA and PEEK implants were implanted and were examined 4 weeks and 12 weeks after implantation with radiology and histology. Commercial titanium dental implants served as controls. RESULTS: The ratio of bone volume to tissue volume of PEEK-HA implants was higher than that of PEEK implants 4 weeks after implantation in the µ-CT analysis. The bone implant contact of PEEK and PEEK-HA implants showed no statistical difference in the histological examination, but newly-formed bone around PEEK-HA implants showed more signs of mineralization than that around PEEK implants. CONCLUSION: The study suggested that bone formation was improved with hydroxyapatite-incorporation in PEEK. Hydroxyapatite-incorporated PEEK implants may represent a potential material for endosseous dental implant.


Assuntos
Implantes Dentários , Cetonas , Implantação Dentária Endóssea , Durapatita , Éter , Osseointegração , Osteogênese , Polietilenoglicóis , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Titânio
15.
ACS Nano ; 14(2): 1296-1318, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32011856

RESUMO

Cell reprogramming is a revolutionized biotechnology that offers a powerful tool to engineer cell fate and function for regenerative medicine, disease modeling, drug discovery, and beyond. Leveraging advances in biomaterials and micro/nanotechnologies can enhance the reprogramming performance in vitro and in vivo through the development of delivery strategies and the control of biophysical and biochemical cues. In this review, we present an overview of the state-of-the-art technologies for cell reprogramming and highlight the recent breakthroughs in engineering biomaterials with micro/nanotechnologies to improve reprogramming efficiency and quality. Finally, we discuss future directions and challenges for reprogramming technologies and clinical translation.


Assuntos
Materiais Biocompatíveis/química , Nanotecnologia , Engenharia Tecidual , Animais , Reprogramação Celular , Humanos , Tamanho da Partícula , Propriedades de Superfície
16.
Nat Commun ; 11(1): 5990, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239608

RESUMO

Bioresorbable electronic stimulators are of rapidly growing interest as unusual therapeutic platforms, i.e., bioelectronic medicines, for treating disease states, accelerating wound healing processes and eliminating infections. Here, we present advanced materials that support operation in these systems over clinically relevant timeframes, ultimately bioresorbing harmlessly to benign products without residues, to eliminate the need for surgical extraction. Our findings overcome key challenges of bioresorbable electronic devices by realizing lifetimes that match clinical needs. The devices exploit a bioresorbable dynamic covalent polymer that facilitates tight bonding to itself and other surfaces, as a soft, elastic substrate and encapsulation coating for wireless electronic components. We describe the underlying features and chemical design considerations for this polymer, and the biocompatibility of its constituent materials. In devices with optimized, wireless designs, these polymers enable stable, long-lived operation as distal stimulators in a rat model of peripheral nerve injuries, thereby demonstrating the potential of programmable long-term electrical stimulation for maintaining muscle receptivity and enhancing functional recovery.


Assuntos
Implantes Absorvíveis , Terapia por Estimulação Elétrica/instrumentação , Traumatismos dos Nervos Periféricos/terapia , Poliuretanos/química , Tecnologia sem Fio/instrumentação , Animais , Modelos Animais de Doenças , Terapia por Estimulação Elétrica/métodos , Feminino , Humanos , Teste de Materiais , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Ratos , Regeneração , Nervo Isquiático/lesões , Nervo Isquiático/fisiologia
17.
J Radiosurg SBRT ; 5(2): 131-144, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29657894

RESUMO

We investigated the effects of multiple planning factors on normal brain dose for single-isocenter VMAT stereotactic radiosurgery (SRS). Ten patients were retrospectively planned using a standardized objective function and all 16 combinations of 2 versus 4 arcs, collimator angle 45° versus selected per beam to minimize area of normal brain exposed in the beams-eye-view, fixed jaw versus following the trailing MLC leaf, and a 2 Gy mean dose objective for healthy brain versus no low dose objective. Limiting the normal brain mean dose in the optimization objective function significantly reduced the low dose spill into the normal brain without changing target coverage. Jaw tracking and appropriate selection of collimator also reduced the low dose volume, but to a lesser extent. To reduce low dose spill into normal brain for single isocenter VMAT radiosurgery of multiple targets, it is important to incorporate a limit on low dose spill into the objective function. This study has implications beyond single-isocenter VMAT radiosurgery. When comparing different inverse-planned treatment techniques, metrics that are important for evaluation of plan quality must be included the objective function.

18.
Colloids Surf B Biointerfaces ; 166: 224-234, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29602078

RESUMO

A well-defined multifunctional brush-type polymeric prodrug covalently linked with an anticancer drug (bufalin, BUF), a tumor-targeting peptide (RGD), and an endosome-escaping polymer, poly(N,N-diethylaminoethyl methacrylate-co-butyl methacrylate (P(DEA-co-BMA)), was developed. Its anticancer performance against colon cancer was investigated in vitro and in vivo. Reversible addition-fragmentation transfer (RAFT) polymerization of oligo(ethylene glycol) monomethyl ether methacrylate (OEGMA), 2-((3-(tert-butoxy)-3-oxopropyl)thio)ethyl methacrylate (BSTMA), and 2-(2-bromoisobutyryloxy)ethylmethacrylate (BIEM) afforded the multifunctional random copolymer, P(OEGMA-co-BSTMA-co-BIEM), in which hydrophilic POEGMA can stabilize nanoparticles in water, PBSTMA can be converted into carboxyl groups, and PBIEM can be employed as a macromolecular atom radical transfer polymerization (ATRP) initiator. The ATRP of DEA and BMA using P(OEGMA-co-BSTMA-co-BIEM) as a macromolecular ATRP initiator led to the formation of the pH-responsive brush-type copolymer, P(OEGMA-co-BSTMA)-g-P(DEA-co- BMA). After hydrolysis by trifluoroacetic acid and post-functionalization the final polymeric prodrug, P(OEGMA-co-BUF-co-RGD)-g-P(DEA-co-BMA), was obtained with a drug content of ∼7.8 wt%. P(OEGMA-co-BUF-co-RGD)-g-P(DEA-co-BMA) can be assembled into nanoparticles (BUF- NP-RGD) in aqueous solution with a diameter of 148.4 ±â€¯0.7 nm and a zeta potential of -7.6 ±â€¯0.4 mV. BUF-NP-RGD exhibited controlled drug release in the presence of esterase. Additionally, P(OEGMA-co- BSMA)-g-P(DEA-co-BMA) showed a significant hemolysis effect at a pH comparable to that of endosomes/lysosomes. Cell viability and a tumor-bearing nude mouse model were employed to evaluate the anticancer efficacy of BUF-NP-RGD. It was revealed that BUF-NP-RGD showed improved anticancer performance compared with that of free BUF both in vitro and in vivo. Histological and immunochemical analysis further demonstrated that BUF-NP-RGD exhibited improved cell apoptosis, angiogenesis inhibition, and an anti-proliferation effect.


Assuntos
Bufanolídeos/química , Bufanolídeos/uso terapêutico , Polímeros/química , Pró-Fármacos/química , Pró-Fármacos/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Endossomos/metabolismo , Metacrilatos/química , Camundongos , Nanopartículas/química , Polietilenoglicóis/química
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