RESUMO
Stretchable hybrid devices have enabled high-fidelity implantable1-3 and on-skin4-6 monitoring of physiological signals. These devices typically contain soft modules that match the mechanical requirements in humans7,8 and soft robots9,10, rigid modules containing Si-based microelectronics11,12 and protective encapsulation modules13,14. To make such a system mechanically compliant, the interconnects between the modules need to tolerate stress concentration that may limit their stretching and ultimately cause debonding failure15-17. Here, we report a universal interface that can reliably connect soft, rigid and encapsulation modules together to form robust and highly stretchable devices in a plug-and-play manner. The interface, consisting of interpenetrating polymer and metal nanostructures, connects modules by simply pressing without using pastes. Its formation is depicted by a biphasic network growth model. Soft-soft modules joined by this interface achieved 600% and 180% mechanical and electrical stretchability, respectively. Soft and rigid modules can also be electrically connected using the above interface. Encapsulation on soft modules with this interface is strongly adhesive with an interfacial toughness of 0.24 N mm-1. As a proof of concept, we use this interface to assemble stretchable devices for in vivo neuromodulation and on-skin electromyography, with high signal quality and mechanical resistance. We expect such a plug-and-play interface to simplify and accelerate the development of on-skin and implantable stretchable devices.
Assuntos
Eletromiografia , Eletrônica Médica , Nanoestruturas , Maleabilidade , Polímeros , Próteses e Implantes , Dispositivos Eletrônicos Vestíveis , Humanos , Nanoestruturas/química , Polímeros/química , Pele , Monitorização Fisiológica , Eletrônica Médica/instrumentação , Eletrônica Médica/métodos , Eletromiografia/instrumentaçãoRESUMO
AIM: To evaluate the association between periodontitis, all-cause and cause-specific mortality, and its prognostic utility among adults with diabetes. MATERIALS AND METHODS: Periodontal health records were retrieved from the NHANES database for 4297 participants with diabetes aged >30 years at baseline during 1988-1994, 1999-2004 and 2009-2014. Multivariable Cox proportional hazards regression model was applied to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for moderate/severe periodontitis with all-cause and cause-specific mortality in participants with diabetes. Area under the curve (AUC) was used to assess predictive value. RESULTS: During a median follow-up of 15.41 years, 1701 deaths occurred. After multivariate adjustments, moderate/severe periodontitis was significantly associated with increased risk of all-cause (HR: 1.27; 95% CI: 1.07-1.50; p = .005) and cardiovascular disease (CVD)-related (HR: 1.35, 95% CI: 1.03-1.76, p = .031) mortality in participants with diabetes. The absolute risk difference based on the cumulative incidence information was 0.022 (5-year, 95% CI: 0.021-0.023) and 0.044 (10-year, 95% CI: 0.041-0.048). Periodontitis improved the prediction of all-cause (AUC: 0.652; 95% CI: 0.627-0.676) and CVD-related (AUC: 0.649; 95% CI: 0.624-0.676) mortality over standard risk factors (all-cause: AUC: 0.631; 95% CI: 0.606-0.656; CVD-related: AUC: 0.629; 95% CI: 0.604-0.655). CONCLUSIONS: Moderate/severe periodontitis is associated with an increased risk of all-cause and CVD-related mortality in adults with diabetes. Periodontitis might represent a marker for residual risk.
Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Periodontite , Adulto , Humanos , Causas de Morte , Estudos de Coortes , Inquéritos Nutricionais , Fatores de Risco , Periodontite/complicações , Periodontite/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologiaRESUMO
Directed differentiation enables the production of a specific cell type by manipulating signals in development. However, there is a lack of effective means to accelerate the regeneration of neurons of particular subtypes for pathogenesis and clinical therapy. In this study, we find that hydroxyapatite (HAp) nanorods promote neural differentiation of neural stem cells due to their chemical compositions. Lysosome-mediated degradation of HAp nanorods elevates intracellular calcium concentrations and accelerates GABAergic neurogenesis. As a mechanism, the enhanced activity of a Ca2+ peak initiated by HAp nanorods leads to the activation of c-Jun and thus suppresses the expression of GABAergic/glutamatergic selection gene TLX3. We demonstrate the capability of HAp nanorods in promoting the differentiation into GABAergic neurons at both molecular and cellular function levels. Given that GABAergic neurons are responsible for various physiological and pathological processes, our findings open up enormous opportunities in efficient and precise stem cell therapy of neurodegenerative diseases.
Assuntos
Nanotubos , Células-Tronco Neurais , Materiais Biocompatíveis , Diferenciação Celular , Sinais (Psicologia) , Durapatita , Neurônios GABAérgicosRESUMO
Elastin-like polypeptides (ELPs) have been proposed as a simple model of intrinsically disordered proteins (IDPs) which can form membraneless organelles by liquid-liquid phase separation (LLPS) in cells. Herein, the behavior of fluorescently labeled ELP is studied in cytomimetic aqueous two-phase system (ATPS) encapsulated protocells that are formed using microfluidics, which enabled confinement, changes in temperature, and statistical analysis. The spatial organization of ELP could be observed in the ATPS. Furthermore, changes in temperature triggered the dynamic formation and distribution of ELP-rich droplets within the ATPS, resulting from changes in conformation. Proteins were encapsulated along with ELP in the synthetic protocells and distinct partitioning properties of these proteins and ELP in the ATPS were observed. Therefore, the ability of ELP to coacervate with temperature can be maintained inside a cell-mimicking system.
Assuntos
Proteínas Intrinsicamente Desordenadas/química , Substâncias Macromoleculares/química , Organelas/química , Polietilenoglicóis/química , TemperaturaRESUMO
Cell membrane asymmetry is a common structural feature of all biological cells. Researchers have tried for decades to better study its formation and its function in membrane-regulated phenomena. In particular, there has been increasing interest in developing synthetic asymmetric membrane models in the laboratory, with the aim of studying basic physical chemistry properties that may be correlated to a relevant biological function. The present article aims to summarize the main presented approaches to prepare asymmetric membranes, which are most often made from lipids, polymers, or a combination of both.
Assuntos
Bicamadas Lipídicas/química , Polímeros/química , Materiais Biomiméticos/químicaRESUMO
BACKGROUND: We aimed to compare the effects of bisphosphonate on the remodeling of irregular bones (the jaw and ilium) in mice after trauma. METHODS: To verify the feasibility of modeling osteonecrosis, 20 mice were injected intraperitoneally with zoledronate and dexamethasone (ZOL&DEX group), dexamethasone (DEX group), or phosphate-buffered saline (PBS) [control (CTR) group]. Mice then underwent extraction of the right maxillary first molar and creation of an artificial bony cavity in the ilium. Bone sections were stained with H&E for morphological studies. To further compare differences between the maxilla and the ilium caused by similar traumas, 80 mice were injected intraperitoneally with ZOL&DEX or PBS. Pathological progression at the injury sites was assessed at 1 day and at 1, 3, and 8 weeks after trauma using micro-computed tomography (CT), H&E and immunohistochemistry analyses, high-performance liquid chromatography-mass spectrometry, and enzyme-linked immunosorbent assay. RESULTS: Only the ZOL&DEX model group effectively developed osteonecrosis. Bony sequestra, osseous sclerosis, unhealed mucosa, and radiopaque alveolar bone were found in the maxilla. In the ilium, there was a lower frequency of osteonecrotic disease and osseous sclerosis, and less suppression of bone remodeling than in the maxilla following long-term bisphosphonate administration. Zoledronate levels were higher in the maxilla. ZOL&DEX treatment suppressed the levels of RANKL and IL-17, but induced an upregulation of osteoprotegerin and FAM20C in both bones. CONCLUSION: Accumulation of bisphosphonate may increase the incidence of osteonecrosis. The RANKL/OPG pathway and IL-17 and FAM20C cytokines play key roles in the progression of pathologically abnormal bone remodeling.
Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/patologia , Conservadores da Densidade Óssea/farmacologia , Remodelação Óssea/efeitos dos fármacos , Dexametasona/farmacologia , Difosfonatos/farmacologia , Imidazóis/farmacologia , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Proteínas da Matriz Extracelular/metabolismo , Feminino , Ílio/efeitos dos fármacos , Ílio/patologia , Imuno-Histoquímica , Interleucina-17/metabolismo , Arcada Osseodentária/efeitos dos fármacos , Arcada Osseodentária/patologia , Maxila/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Ligante RANK/metabolismo , Ácido ZoledrônicoRESUMO
Alzheimer's disease (AD), which is a prevailing type of dementia, presents a significant global health concern. The current therapies do not meet clinical expectations. Amyloid-beta (Aß) has been found to induce endogenous formaldehyde (FA) accumulation by inactivating FA dehydrogenase (FDH); in turn, excessive FA triggers Aß aggregation that eventually leads to AD onset. Hence, scavenging FA by astaxanthin (ATX, a strong exogenous antioxidant) may be pursued as a promising disease-modifying approach. Here, we report that liposomal nanoparticles coupled with PEG (PEG-ATX@NPs) could enhance water-solubility of ATX and alleviate cognitive impairments by scavenging FA and reducing Aß deposition. To enable drug delivery to the brain, liposomes were used to encapsulate ATX and then coupled with PEG, which produced liposomal nanoparticles (PEGATX@NPs) with a diameter of <100 nm. The PEG-ATX@NPs reduced Aß neurotoxicity by both degrading FA and reducing FA-induced Aß assembly in vitro. Intraperitoneal administration of PEG-ATX@NPs in APPswe/PS1dE9 mice (APP/PS1, a familial model of AD), not only decreased the levels of brain FA and malondialdehyde (MDA, a typical product of oxidative stress), but also attenuated both intracellular Aß oligomerization and extracellular Aß-related senile plaque (SP) formation. These pathological changes were accompanied by rescued ability of spatial learning and memory. Collectively, PEG-ATX@NPs improved the water-solubility, bioavailability, and effectiveness of ATX. Thus, it has the potential to be developed as a safe and effective strategy for treating AD.
Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Xantofilas , Animais , Camundongos , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide , Lipossomos , Camundongos Transgênicos , Fenótipo , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Água , Xantofilas/administração & dosagem , Xantofilas/químicaRESUMO
Supramolecular assembly: Spherical and stable hybrid assemblies based on a cationic polymer with spermine side chains and an anionic Gd(3+)-containing polyoxometalate cluster (GdW) are prepared by electrostatic interaction. The T1-weighted MRI performance of GdW is enhanced about three times in the assemblies; meanwhile, the assemblies show good biocompatibility, which enables them to be promising candidates for MRI contrast agents.
Assuntos
Cátions/química , Meios de Contraste/química , Polímeros/química , Espermina/química , Compostos de Tungstênio/química , Gadolínio/química , Imageamento por Ressonância MagnéticaRESUMO
The aim of this study was to investigate the feasibility and advantages of the dual delivery of bone morphogenetic protein-2 (BMP-2) and basic fibroblast growth factor (bFGF) from nano-composite scaffolds (PLGA/PCL/nHA) loaded with vascular stents (PLCL/Col/nHA) for large bone defect regeneration in rabbit mandibles. Thirty-six large bone defects were repaired in rabbits using engineering bone composed of allogeneic bone marrow mesenchymal stem cells (BMSCs), bFGF, BMP-2 and scaffolds composed of PLGA/PCL/nHA loaded with PLCL/Col/nHA. The experiments were divided into six groups: BMSCs/bFGF/BMP-2/scaffold, BMSCs/BMP-2/scaffold, BMSCs/bFGF/scaffold, BMSCs/scaffold, scaffold alone and no treatment. Sodium alginate hydrogel was used as the carrier for BMP-2 and bFGF and its features, including gelling, degradation and controlled release properties, was detected by the determination of gelation and degradation time coupled with a controlled release study of bovine serum albumin (BSA). AlamarBlue assay and alkaline phosphatase (ALP) activity were used to evaluate the proliferation and osteogenic differentiation of BMSCs in different groups. X-ray and histological examinations of the samples were performed after 4 and 12 weeks post-implantation to clarify new bone formation in the mandible defects. The results verified that the use of sodium alginate hydrogel as a controlled release carrier has good sustained release ability, and the combined application of bFGF and BMP-2 could significantly promote the proliferation and osteogenic differentiation of BMSCs (p < 0.05 or p < 0.01). In addition, X-ray and histological examinations of the samples exhibited that the dual release group had significantly higher bone formation than the other groups. The above results indicate that the delivery of both growth factors could enhance new bone formation and vascularization compared with delivery of BMP-2 or bFGF alone, and may supply a promising way of repairing large bone defects in bone tissue engineering.
Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Regeneração Óssea/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Mandíbula/patologia , Nanocompostos/química , Stents , Alicerces Teciduais/química , Alginatos/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Materiais Biocompatíveis/farmacologia , Prótese Vascular , Densidade Óssea/efeitos dos fármacos , Bovinos , Proliferação de Células/efeitos dos fármacos , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Implantes Experimentais , Mandíbula/diagnóstico por imagem , Mandíbula/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Coelhos , Radiografia , Soroalbumina Bovina/metabolismoRESUMO
Bacterial infections caused by the growth and reproduction of pathogenic bacteria on wounds are one of the main reasons that hinder wound healing. Antibacterial wound dressings protect wounds from bacterial infections. Herein, we developed a polymeric antibacterial composite film using polyvinyl alcohol (PVA) and sodium alginate (SA) as the substrate. The film used praseodymium-doped yttrium orthosilicate (Y2SiO5: Pr3+, YSO-Pr) to convert visible light into short-wavelength ultraviolet light (UVC) to kill bacteria. The YSO-Pr/PVA/SA showed upconversion luminescence in photoluminescence spectrometry tests, and the emitted UVC inhibited Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria in antibacterial tests. In vivo animal tests showed that YSO-Pr/PVA/SA is effective and safe for inhibiting bacteria in real wounds. The in vitro cytotoxicity test further confirmed the good biocompatibility of the antibacterial film. In addition, YSO-Pr/PVA/SA exhibited sufficient tensile strength. Overall, this study demonstrates the potential of upconversion materials for use in medical dressings.
Assuntos
Polímeros , Infecções Estafilocócicas , Animais , Polímeros/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Álcool de Polivinil/química , Luz , Bactérias , Escherichia coli , Alginatos/químicaRESUMO
Bacterial infections on open wounds have always been a threat to human health. Herein, we prepared a silver (Ag)-polydopamine (PDA)/bacterial cellulose (BC)-chitosan (CTS) film using biological self-generation and in situ reduction. CTS was added to culture medium to allow BC to intertwine with CTS during film formation. Silver nitrate was reduced in situ to Ag nanoparticles under ultraviolet irradiation, and the nanoparticles were well dispersed in the BC-CTS film with the help of PDA, which worked synergistically with the CTS. The Ag-PDA/BC-CTS film was enriched in functional groups, and it had good tensile and swelling properties. The inhibition film demonstrated broad-spectrum inhibition of Gram-positive and Gram-negative bacteria, and this inhibition was maintained at more than 80% after 48 h of continuous use. The good biocompatibility of the film was verified using NIH3T3 fibroblasts. The results suggested that the Ag-PDA/BC-CTS film inhibited the growth of harmful bacteria while having little effect on healthy cells.
Assuntos
Quitosana , Nanopartículas Metálicas , Animais , Antibacterianos/farmacologia , Bactérias , Celulose/farmacologia , Quitosana/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Humanos , Nanopartículas Metálicas/toxicidade , Camundongos , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Prata/farmacologiaRESUMO
Masks are key to personal protection and their bacteriostatic properties, which are generally overlooked, should be maximized. Towards this goal, a YPS-Pr-Li/BC upconversion antibacterial composite film was prepared by mixing upconversion powder with bacterial cellulose (BC) using a vacuum assisted method. When combined with the low surface energy of stearic acid (STA), the resulting YPS-Pr-Li/BC/STA film had an improved hydrophobic surface. The developed film was characterized by FT-IR, SEM, XRD, and fluorescence spectrophotometry. The results showed that the composite film was successfully prepared and had ultraviolet, visible upconversion luminescence. The bacteriostatic experiments showed that the material had excellent bacteriostatic performance against E. coli and S. aureus under visible light, with a bacteriostatic rate reaching 99 %. The in-vitro cytotoxicity tests showed that YPS-Pr-Li/BC/STA had excellent biocompatibility and could be used in personal protective clothing with close contact with human skin.
Assuntos
Celulose , Staphylococcus aureus , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias , Celulose/química , Celulose/farmacologia , Escherichia coli , Humanos , Máscaras , Pós , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
The association between micronutrient intake and the risk of periodontitis has received much attention in recent years. However, most studies focused on the linear relationship between them. This study aimed to explore the dose-response association between micronutrient intake and periodontitis. A total of 8959 participants who underwent a periodontal examination, and reported their micronutrient intake levels were derived from the US National Health and Nutrition Examination Survey (NHANES, 2009-2014) database. Logistic regression was performed to evaluate associations between micronutrient intake and periodontitis after propensity score matching (PSM), and restricted cubic splines (RCS) analysis was conducted to explore the dose-response associations. Following PSM, 5530 participants were included in the RCS analysis. The risk of periodontitis was reduced with sufficient intake of the following micronutrients: vitamin A, vitamin B1, vitamin B2, and vitamin E. In addition, the risk of periodontitis was increased with excessive intake of the following micronutrients: vitamin B1 (1.8 mg/day, males; 1.3 mg/day, females), vitamin C (90 mg/day, males), and copper (1.1 mg/day, combined). In conclusion, a linear association was found between vitamin A, vitamin B2, vitamin C, and copper and periodontitis-namely, a sufficient intake of vitamin A and vitamin B2 might help reduce the prevalence of periodontitis; by contrast, a high intake of vitamin C and copper increased the risk. In addition, a nonlinear dose-response association was found for the incidence of periodontitis with vitamin B1 and vitamin E. When within reasonable limits, supplemental intake helped reduce the prevalence of periodontitis, while excessive intake did not help significantly and might even increase the risk. However, confounding factors, such as health awareness, should still be considered.
Assuntos
Periodontite , Vitamina A , Ácido Ascórbico , Cobre , Ingestão de Alimentos , Feminino , Humanos , Masculino , Micronutrientes , Inquéritos Nutricionais , Periodontite/epidemiologia , Riboflavina , Tiamina , Vitamina E , VitaminasRESUMO
Microbial infections are currently one of the world's major public health concerns, the evolution of which has resulted in the development of multiple tolerances (not just drug or antibiotic resistance), including pH (from extremely acidic to alkaline). Currently various types of antimicrobials have been developed. Although effective, they seldom work in the full pH range due to the existence of acid-/base-reaction sites. Here, we found that polythiophene (PT10), a cationic polymer, was capable of both broad-spectrum photo-antimicrobial activity (Gram positive, Gram negative, Fungal, and cyano-bacteria) and broad pH responsiveness (constant 1O2 generation at pH 2-13). The half-maximal inhibitory concentrations (IC50) of PT10 for bacteria living in acidic, neutral, and alkaline media were generally lower than 2 µg mL-1 (except M. aeruginosa, pH 12, â¼30 µg mL-1), which were much lower than common antibiotics and other photosensitizers. Besides, the excellent photostability of PT10 allowed long-term light irradiation for antimicrobial performance. In real-world applications, PT10 was explored for the successful in vivo therapy of oral Candidiasis infection under extreme acidic conditions (pH < 3) and the removal of M. aeruginosa at pH 12. Such near full pH, broad-spectrum photo-antimicrobial activity of polythiophene is appealing for extremely acidic or alkaline applications, such as oral infections, vaginitis, and blooms.
Assuntos
Antibacterianos , Anti-Infecciosos , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Polímeros/farmacologia , TiofenosRESUMO
Hydrogels with high mechanical strength and injectability have attracted extensive attention in biomedical and tissue engineering. However, endowing a hydrogel with both properties is challenging because they are generally inversely related. In this work, by constructing a multi-hydrogen-bonding system, a high-strength and injectable supramolecular hydrogel is successfully fabricated. It is constructed by the self-assembly of a monomeric nucleoside molecular gelator (2-amino-2'-fluoro-2'-deoxyadenosine (2-FA)) with distilled water/phosphate buffered saline as solvent. Its storage modulus reaches 1 MPa at a concentration of 5.0 wt%, which is the strongest supramolecular hydrogel comprising an ultralow-molecular-weight (MW < 300) gelator. Furthermore, it exhibits excellent shear-thinning injectability, and completes the sol-gel transition in seconds after injection at 37 °C. The multi-hydrogen-bonding system is essentially based on the synergistic interactions between the double NH2 groups, water molecules, and 2'-F atoms. Furthermore, the 2-FA hydrogel exhibits excellent biocompatibility and antibacterial activity. When applied to rat molar extraction sockets, compared to natural healing and the commercial hemorrhage agent gelatin sponge, the 2-FA hydrogel exhibits faster degradation and induces less osteoclastic activity and inflammatory infiltration, resulting in more complete bone healing. In summary, this study provides ideas for proposing a multifunctional, high-strength, and injectable supramolecular hydrogel for various biomedical engineering applications.
Assuntos
Hidrogéis , Nucleosídeos , Animais , Bandagens , Hidrogéis/farmacologia , Ratos , Engenharia Tecidual , CicatrizaçãoRESUMO
The combination of alginate, hyaluronic acid and multivalent ions have been reported to form alginate-hyaluronic acid ionic-crosslinking hydrogels for biomedical applications. However, injectable alginate-hyaluronic acid ionic-crosslinking hydrogels with satisfactory shear-thinning property have rarely been reported. In this study, we successfully developed an ionic-crosslinked alginate-hyaluronic acid hydrogel by simple assembly of alginate-hyaluronic acid mixture and Fe3+ complex. This hydrogel could fully recover within seconds after damaged, while displayed shear thinning behavior and good injectability which were contributed by the reversible and dynamic metal-ligand interactions formed via ferric ions and carboxyl groups of the polymers. Moreover, the local degradation of this hydrogel giving the hydrogel sustained ferric ions release property, of which led to potential long-term antibacterial activities against multiple types of bacteria including gram-negative Escherichia coli and gram-positive Staphylococcus aureus, as well as representative oral pathogenic bacteria Streptococcus mutans and Porphyromonas gingivalis.
Assuntos
Alginatos/química , Anti-Infecciosos/química , Compostos Férricos/química , Ácido Hialurônico/química , Hidrogéis/química , Animais , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Feminino , Compostos Férricos/metabolismo , Humanos , Hidrogéis/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Porphyromonas/efeitos dos fármacos , Reologia , Pele/efeitos dos fármacos , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacosRESUMO
Design of reversible organelle-like microcompartments formed by liquid-liquid phase separation in cell-mimicking entities has significantly advanced the bottom-up construction of artificial eukaryotic cells. However, organizing the formation of artificial organelle architectures in a spatiotemporal manner within complex primitive compartments remains scarcely explored. In this work, thermoresponsive hybrid polypeptide-polymer conjugates are rationally engineered and synthesized, resulting from the conjugation of an intrinsically disordered synthetic protein (IDP), namely elastin-like polypeptide, and synthetic polymers (poly(ethylene glycol) and dextran) that are widely used as macromolecular crowding agents. Cell-like constructs are built using droplet-based microfluidics that are filled with such bioconjugates and an artificial cytoplasm system that is composed of specific polymers conjugated to the IDP. The distinct spatial organizations of two polypeptide-polymer conjugates and the dynamic assembly and disassembly of polypeptide-polymer coacervate droplets in response to temperature are studied in the cytomimetic protocells. Furthermore, a monoblock IDP with longer length is concurrently included with bioconjugates individually inside cytomimetic compartments. Both bioconjugates exhibit an identical surfactant-like property, compartmentalizing the monoblock IDP coacervates via temperature control. These findings lay the foundation for developing hierarchically structured synthetic cells with interior organelle-like structures which could be designed to localize in desired phase-separated subcompartments.
Assuntos
Células Artificiais/química , Proteínas Intrinsicamente Desordenadas/química , Substâncias Macromoleculares/química , Organelas/química , Polímeros/química , Microfluídica/métodosRESUMO
In order to explore the mechanism underlying chemosensation in Eocanthecona furcellata, the external morphology of its antennae and the type, quantity, distribution and ultrastructure of the sensilla were observed on both sexes of adults and 5th-instar nymphs using scanning electron microscopy. The results showed that the antennae of E. furcellata consisted of three parts: scape, pedicel and flagellum. There were five types of sensilla on the antennae, which included sensilla trichoidea (ST), sensilla chaetica (SCh), sensilla coeloconica (SCo), sensilla basiconica (SB) and squamifornia denticles (SD). Further, there were 4 subtypes of ST and SB and 2 subtypes of SCo and SCh. The number of sensilla on nymphs was significantly lower than that on adults. The antennae of adults showed sexual dimorphism, as the number of sensilla on female adults was higher than that on male adults. SB4 was found only on females and SCo2 was found only on males. These inter-sexual differences may be related to chemoreception of sex pheromone and chemical predation location. The morphology and putative functions of each sensilla were compared and discussed. These results provide a reference for further study of the behavioral biology, chemical ecology and electrophysiology of insects, and also provides a scientific basis for new ways of biological control.
Assuntos
Heterópteros , Sensilas , Animais , Antenas de Artrópodes , Feminino , Masculino , Microscopia Eletrônica de Varredura , Caracteres SexuaisRESUMO
Photothermal therapy (PTT) is a promising treatment for tumors due to its efficiency and non-invasiveness. However, during the PTT treatment, reactive oxygen species (ROS) are produced in response to hyperthermia and thus harm the neighboring normal cells. In this work, a multifunctional theranostic agent (Se@SiO2@Au-PEG/DOX NCs) was exploited to solve this problem by introducing selenium, which can efficiently prevent normal cells from oxidative damage by scavenging reactive oxygen species during photothermal therapy. In addition, the Se@SiO2@Au-PEG/DOX nanocomposites (NCs) not only exhibited excellent properties of combined chemo-thermal synergistic therapy, but also showed no appreciable toxicity towards normal tissues due to the protective effect for continuous release of selenium. Thus, the fabricated Se@SiO2@Au-PEG/DOX NCs provide an integrated solution to overcome the limitations of selenium and PTT, and demonstrate great prospects as a safe and highly reliable theranostic agent.
Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Fotoquimioterapia , Nanomedicina Teranóstica , Células A549 , Animais , Antibióticos Antineoplásicos/síntese química , Antibióticos Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Doxorrubicina/síntese química , Doxorrubicina/química , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Ouro/química , Ouro/farmacologia , Humanos , Camundongos , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Selênio/química , Selênio/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologiaRESUMO
Supramolecular hydrogel delivery systems have attracted widely attention owing to incorporating various therapeutic agents in carriers to decrease unpredictable toxicities, improve curative efficacy, and protect drug bioactivity. Nonetheless, the dual-functional supramolecular hydrogel integrating localized delivery and antineoplastic activities in one system have rarely observed. In this study, we successfully developed a novel supramolecular hydrogel, isoguanosine-borate-guanosine (isoGBG), with reversibly and dynamic borate ester bonds formed via boric acids and diols derived from nature products guanosine and isoguanosine in one pot by following a simple procedure. Both in vivo and in vitro results demonstrated that the isoGBG hydrogel not only displays excellent stability, self-healing properties and biocompatibility, but also has highly anti-tumor activities through inducing tumor cell apoptosis and excellent inhibition effect of tumor recurrence. These findings suggested that isoGBG hydrogel can serve as a dual-function hydrogel system integrating drug carrier and anti-cancer compound in one system, which provided a promising strategy for the design of functional supramolecular hydrogel in the local management of cancer in the future.