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1.
Nature ; 610(7930): 74-80, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36163287

RESUMO

The adverse impact of particulate air pollution on human health1,2 has prompted the development of purification systems that filter particulates out of air3-5. To maintain performance, the filter units must inevitably be replaced at some point, which requires maintenance, involves costs and generates solid waste6,7. Here we show that an ion-doped conjugated polymer-coated matrix infiltrated with a selected functional liquid enables efficient, continuous and maintenance-free air purification. As the air to be purified moves through the system in the form of bubbles, the functional fluid provides interfaces for filtration and for removal of particulate matter and pollutant molecules from air. Theoretical modelling and experimental results demonstrate that the system exhibits high efficiency and robustness: its one-time air purification efficiency can reach 99.6%, and its dust-holding capacity can reach 950 g m-2. The system is durable and resistant to fouling and corrosion, and the liquid acting as filter can be reused and adjusted to also enable removal of bacteria or odours. We anticipate that our purification approach will be useful for the development of specialist air purifiers that might prove useful in a settings such as hospitals, factories and mines.


Assuntos
Absorção Fisico-Química , Poluentes Atmosféricos , Filtração , Material Particulado , Poluentes Atmosféricos/química , Poluentes Atmosféricos/isolamento & purificação , Bactérias/isolamento & purificação , Poeira/prevenção & controle , Filtração/instrumentação , Filtração/métodos , Humanos , Odorantes/prevenção & controle , Material Particulado/química , Material Particulado/isolamento & purificação , Polímeros/química , Resíduos Sólidos
2.
Environ Monit Assess ; 196(4): 350, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38460005

RESUMO

In order to clarify the characteristics of microplastics in the atmosphere of Anyang city, TSP, PM10, and PM2.5 samples are collected when the ambient air quality is good, slightly polluted, and severely polluted. After pretreatment, the physical and chemical characteristics are observed and identified by using stereomicroscope and micro-infrared spectrometer. The results show that the average abundance of microplastics is 0.19 items/m3, 0.26 items/m3, and 0.42 items/m3, respectively, when the ambient air quality is good, light pollution, and heavy pollution in Anyang City. It can be seen that with the decline of ambient air quality, the average abundance of microplastics in TSP, PM2.5, and PM10 gradually increases. The black fiber strip microplastics account for about 80% of the total TSP, PM2.5, and PM10 in the ambient air of Anyang City, followed by yellow flake and black granular microplastics and a small amount of green, red, and blue fiber strip microplastics. AQI has a good correlation with the abundance of microplastics in TSP, PM10, and PM2.5, and the maximum microplastic trapping effect could be obtained according to the sampling method of PM2.5 in the ambient air. The main components of microplastics are cellophane, followed by PET and EVA. The explorations of human respiratory exposure risk assessment show that with the increase of AQI, the daily intake of microplastics in adults also increased. At high levels of pollution, the human body breathes an average of 222 ± 5 microplastics per day.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Adulto , Humanos , Poluentes Atmosféricos/análise , Microplásticos , Plásticos , Monitoramento Ambiental/métodos , Poluição do Ar/análise , Atmosfera , Material Particulado/análise
3.
Angew Chem Int Ed Engl ; 63(1): e202311678, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37963813

RESUMO

Due to their sequence-directed functions and excellent biocompatibility, smart DNA microgels have attracted considerable research interest, and the combination of DNA microgels with functional nanostructures can further expand their applications in biosensing and biomedicine. Gallium-based liquid metals (LMs) exhibiting both fluidic and metallic properties hold great promise for the development of smart soft materials; in particular, LM particles upon sonication can mediate radical-initiated polymerization reactions, thus allowing the combination of LMs and polymeric matrix to construct "soft-soft" materials. Herein, by forming active surfaces under sonication, LM nanoparticles (LM NPs) initiated localized radical polymerization reactions allow the combination of functional DNA units and different polymeric backbones to yield multifunctional core/shell microgels. The localized polymerization reaction allows fine control of the microgel compositions, and smart DNA microgels with tunable catalytic activities can be constructed. Moreover, due to the excellent photothermal effect of LM NPs, the resulting temperature gradient between microgels and surrounding solution upon NIR light irradiation can drive the oriented locomotion of the microgels, and remote control of the activity of these smart microgels can be achieved. These microgels may hold promise for various applications, such as the development of in vivo and in vitro biosensing and drug delivery systems.


Assuntos
Gálio , Microgéis , Polímeros Responsivos a Estímulos , Microgéis/química , Polímeros/química , DNA/química
4.
Small ; 16(42): e1906998, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32985098

RESUMO

As a crucial instinct for the survival of organisms, adaptive smart deformation has been well shown via profusely astounding examples within biological morphogenesis in nature, which inspired the construction of biomimetic shape-morphing materials with controlled actuating behaviors. Herein, the construction of nature-inspired bilayer hydrogel film actuators, composed of a polyacrylamide hydrogel passive layer and a polyacrylamide-DNA hybrid hydrogel active layer, which exhibited programmable stimuli-responsive and reversible macroscopic shape deformations directed by the sequence of DNA crosslinking units in the active layer, is reported. As a proof-of-concept, the introduction of DNA i-motif based crosslinking structures into the active layer, which can undergo pH-stimulated formation and dissociation of crosslinking between polymers and therefore change the crosslinking density of the active layer, lead to the redistribution of the internal stresses within the bilayer structure, and result in the pH-stimulated shape deformations. By programming the sequence of DNA units in the active layer, a Ag+ /Cysteamine-stimulated bilayer DNA hybrid hydrogel film actuator is further constructed and exhibits excellent actuation behaviors. Thanks to the micrometer-scale thickness of the films, these actuators exhibit a high degree of macroscopic and reversible shape deformations at high speed, which may find use in future smart biosensing and biomedical applications.


Assuntos
DNA , Hidrogéis , Resinas Acrílicas , Metilgalactosídeos
5.
Eur Arch Otorhinolaryngol ; 275(6): 1579-1586, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29696368

RESUMO

PURPOSE: Both surgical treatment and non-surgical treatment are suggested by clinicians for children with habitual snoring related to adenotonsillar hypertrophy; However, how should the decision be made remains unclear. The objective of this study was to investigate potential predictors for the treatment decision, i.e., surgical treatment vs wait and see in children with habitual snoring related to adenoidal and/or tonsillar hypertrophy. METHODS: Children with complaints of snoring and/or apnea associated with adenotonsillar hypertrophy who received polysomnography (PSG) monitoring at our Hospital were recruited. After at least 6 months, the subjects were followed up and grouped according to whether or not they had received adenoidectomy and/or tonsillectomy (AT) execution. The heights, weights, as well as the quality of life (assessed using the obstructive sleep apnea-18 (OSA-18) quality of life questionnaire) and baseline PSG of the subjects were recorded and compared. Two logistic regressions were performed to reveal the factors influencing decision-making on conducting AT. RESULTS: A total of 509 children were finally included (345 males and 164 females). Among these children, 287 eventually received AT. Significant differences in age, scores for item 1 and 5 of the OSA-18, apnea-hypopnea index, obstructive apnea index, obstructive apnea-hypopnea index (OAHI), and Lowest arterial oxygen saturation (P < 0.05) were observed between groups. By multivariate logistic regression, the factors that influenced the surgical decision were identified as follows: age < 7 years (P = 0.008: odds ratio [OR] = 1.667, 95% confidence interval [CI] 1.140-2.438), score for item 5 of OSA-18 > 4 points (P = 0.042: OR = 1.489, 95% CI 1.014-2.212) and OAHI > 1/h (P = 0.044: OR = 1.579, 95% CI 1.013-2.463). CONCLUSION: School-age children aged < 7 years, with OAHI > 1/h and mouth breathing scored > 4 points were more likely to receive AT during the disease process and thus require increased attention.


Assuntos
Tonsila Faríngea/patologia , Tonsila Palatina/patologia , Polissonografia , Qualidade de Vida , Ronco/etiologia , Adenoidectomia , Tonsila Faríngea/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Hipertrofia/cirurgia , Modelos Logísticos , Masculino , Razão de Chances , Tonsila Palatina/cirurgia , Seleção de Pacientes , Valor Preditivo dos Testes , Ronco/cirurgia , Inquéritos e Questionários , Tonsilectomia
6.
Pak J Pharm Sci ; 28(2 Suppl): 807-10, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25796158

RESUMO

This paper aims to explore the antibacterial property of nano Ag/TiO2 coating bracket for the common bacteria in oral cavity, and discuss its biocompatibility. Micro morphology in the surface of nano Ag/TiO2 coating bracket was detected by scanning electron microscope (SEM), and surface roughness of ordinary mental bracket, nano TiO2 coating bracket and nano Ag/TiO2 coating bracket were measured. First, antibacterial property of nano Ag/TiO2 coating bracket on the common bacteria in oral cavity was studied by sticking membrane method. Secondly, bonding strength of nano TiO2 coating and nano Ag/TiO2 coating bracket in groups were detected by scratching test. The result showed that, the synthetic nano Ag/TiO2 coating was nanogranular films with rigorous organizational structure, presenting as smooth and clean surface, and antibacterial rate of nano Ag/TiO2 coating for the common bacteria in oral cavity for 20 min was more than 79% in the dark. All the findings suggested that, nano Ag/TiO2 coating bracket not only has antibacterial effect but also has good biocompatibility, therefore, it can satisfy the clinical request of orthodontic treatment.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Nanopartículas Metálicas , Boca/microbiologia , Desenho de Aparelho Ortodôntico , Braquetes Ortodônticos , Compostos de Prata/farmacologia , Titânio/farmacologia , Antibacterianos/química , Bactérias/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Microscopia Eletrônica de Varredura , Processos Fotoquímicos , Compostos de Prata/química , Propriedades de Superfície , Fatores de Tempo , Titânio/química
7.
J Craniofac Surg ; 25(2): e197-202, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24469368

RESUMO

This retrospective study describes various buccinator musculomucosal flaps for the repair of palatal fistulae. Twenty-two palatal fistulae were repaired at our institution between 2002 and 2012 by buccinator musculomucosal flaps with superior-anterior or posterior pedicles. Seventeen patients were treated with posteriorly pedicled flaps, 7 of whom had lengthening of the soft palate and 10 of whom had simultaneously repaired severe lateral palatal scarring. Five patients with anterior or midpalatal fistulae were treated with superior-anteriorly pedicled flaps. All but 4 of the 22 patients had satisfactory results. Four patients had recurrent fistulae, 2 resulting from flap tip necrosis and 2 from wound dehiscence. Follow-up was from 5 to 72 months. None of the patients had facial nerve injury, limited mouth opening, or difficulty chewing. We evaluated the factors that could cause complications, such as flap pattern, location of fistula, and size of palate defect. No statistically significant differences were found in the complication rates among different groups. In conclusion, the buccinator musculomucosal flap is reliable and versatile, with rich vascularity and flexible design. The flap is a good option for fistula repair, especially for larger fistulae at the anterior portion of the hard palate or at the junction of hard and soft palate, where surrounding soft tissues are stiff, scarred, and difficult to mobilize.


Assuntos
Mucosa Bucal/transplante , Retalho Miocutâneo/cirurgia , Fístula Bucal/cirurgia , Palato/cirurgia , Complicações Pós-Operatórias/cirurgia , Retalhos Cirúrgicos/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Fissura Palatina/cirurgia , Feminino , Humanos , Lactente , Masculino , Recidiva , Reoperação , Estudos Retrospectivos , Adulto Jovem
8.
Nurs Open ; 11(2): e2107, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38391098

RESUMO

BACKGROUND: Changes to the wound dressing frequently cause pain. Some adverse side effects of pharmacologic pain management may cause problems or even impede wound healing. There is no systematic study of non-pharmacologic therapies for pain during wound dressing changes, despite the gradual promotion of non-pharmacologic pain reduction methods. OBJECTIVES: To give clinical wound pain management a new direction, locating and assessing non-pharmacological interventions regarding pain brought on by wound dressing changes are necessary. METHOD: The researchers conducted a comprehensive literature review on non-pharmacological interventions for pain during wound dressing changes across five databases: PubMed, Web of Science, Medline, Embase, and the Cochrane Library spanning the period from January 2010 to September 2022. The evaluation of literature and data extraction was carried out independently by two researchers, and in cases of disagreement, a third researcher participated in the deliberation. To assess the risk of bias in the literature, the researchers utilised the Cochrane Handbook for Reviews of Interventions, version 5.1.0. RESULTS: In total, 951 people were involved in 11 investigations covering seven non-pharmacological therapies. For pain triggered by dressing changes, virtual reality (VR) distraction, auditory and visual distractions, foot reflexology, religious and spiritual care, and guided imaging demonstrated partially positive effects, with hypnosis therapy and jaw relaxation perhaps having a weak effect. CONCLUSION: The key to managing wounds is pain management. According to our review, there is some indication that non-pharmacologic interventions can help patients feel less discomfort when having their wound dressings changed. However, the evidence supporting this view is weak. It needs to be corroborated by future research studies with multicentre and large samples. To promote and use various non-pharmacologic interventions in the future, it is also necessary to build standardised and homogenised paths for their implementation.


Assuntos
Bandagens , Dor , Ferimentos e Lesões , Humanos , Bandagens/efeitos adversos , Dor/etiologia
9.
CNS Neurosci Ther ; 30(3): e14460, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37718506

RESUMO

BACKGROUND: Oxidative stress is an early event in the development of Alzheimer's disease (AD) and maybe a pivotal point of interaction governing AD pathogenesis; oxidative stress contributes to metabolism imbalance, protein misfolding, neuroinflammation and apoptosis. Excess reactive oxygen species (ROS) are a major contributor to oxidative stress. As vital sources of ROS, mitochondria are also the primary targets of ROS attack. Seeking effective avenues to reduce oxidative stress has attracted increasing attention for AD intervention. METHODS: We developed liposome-packaged Ligustilide (LIG) and investigated its effects on mitochondrial function and AD-like pathology in the APPswe/PS1dE9 (APP/PS1) mouse model of AD, and analyzed possible mechanisms. RESULTS: We observed that LIG-loaded liposome (LIG-LPs) treatment reduced oxidative stress and ß-amyloid (Aß) deposition and mitigated cognitive impairment in APP/PS1 mice. LIG management alleviated the destruction of the inner structure in the hippocampal mitochondria and ameliorated the imbalance between mitochondrial fission and fusion in the APP/PS1 mouse brain. We showed that the decline in cAMP-dependent protein kinase A (PKA) and A-kinase anchor protein 1 for PKA (AKAP1) was associated with oxidative stress and AD-like pathology. We confirmed that LIG-mediated antioxidant properties and neuroprotection were involved in upregulating the PKA/AKAP1 signaling in APPswe cells in vitro. CONCLUSION: Liposome packaging for LIG is relatively biosafe and can overcome the instability of LIG. LIG alleviates mitochondrial dysfunctions and cognitive impairment via the PKA/AKAP1 signaling pathway. Our results provide experimental evidence that LIG-LPs may be a promising agent for AD therapy.


Assuntos
4-Butirolactona/análogos & derivados , Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/metabolismo , Lipossomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Lipopolissacarídeos , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Mitocôndrias/metabolismo , Transdução de Sinais , Cognição , Modelos Animais de Doenças , Precursor de Proteína beta-Amiloide/metabolismo
10.
Nanomedicine ; 9(7): 903-11, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23352802

RESUMO

A near infrared (NIR) triggered drug delivery platform based on the chitosan-modified chemically reduced graphene oxide (CRGO) incorporated into a thermosensitive nanogel (CGN) was developed. CGN exhibited an NIR-induced thermal effect similar to that of CRGO, reversible thermo-responsive characteristics at 37-42 °C and high doxorubicin hydrochloride (DOX) loading capacity (48 wt%). The DOX loaded CGN (DOX-CGN) released DOX faster at 42 °C than at 37 °C. The fluorescence images revealed DOX expression in the cytoplasm of cancer cells when incubated with DOX-CGN at 37 °C but in the nucleus at 42 °C. Upon irradiation with NIR light (808 nm), a rapid, repetitive DOX release from the DOX-CGN was observed. Furthermore, the cancer cells incubated with DOX-CGN and irradiated with NIR light displayed significantly greater cytotoxicity than without irradiation owing to NIR-triggered increase in temperature leading to nuclear DOX release. These results demonstrate CGN's promising application for on-demand drug release by NIR light. FROM THE CLINICAL EDITOR: These investigators report the successful development of a novel near infrared triggered drug delivery platform based on chitosan-modified chemically reduced graphene oxide (CRGO) incorporated into a thermosensitive nanogel (CGN).


Assuntos
Quitosana/química , Doxorrubicina/farmacologia , Grafite/química , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quitosana/toxicidade , Preparações de Ação Retardada , Doxorrubicina/química , Endocitose/efeitos dos fármacos , Grafite/toxicidade , Hidrodinâmica , Raios Infravermelhos , Camundongos , Nanogéis , Polietilenoglicóis/toxicidade , Polietilenoimina/toxicidade , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Temperatura
11.
NPJ Biofilms Microbiomes ; 9(1): 75, 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37805507

RESUMO

Plaque accumulation and microbial community changes are important causes of periodontal disease. Cleaned plaque microorganisms will reattach to form biofilms, but the recovery and outcome of plaque microbial communities in different periodontal health states remain unknown. In this study, we tracked the biofilm remodeling process in 206 dental plaque samples from 40 healthy periodontal, gingivitis and periodontitis volunteers at 6 time points before and after supragingival scaling. We found that microbial communities of different periodontal states changed asynchronously during the process, and the more severe the periodontal disease condition, the more lagged the recovery of plaque microorganisms to their original state after cleaning; this reflected a higher degree of plaque development in periodontitis samples. The plaque index and bleeding index were significantly correlated with plaque recovery, especially the recovery of bacteria such as Abiotrophia and Capnocytophaga. Meanwhile, we found that the microbial community structure of different periodontal health states was most similar at the Day 3 after plaque cleaning, and the communities gradually differentiated and developed in different directions. Abiotrophia and other bacteria might play an important role in determining the development trend of plaque biofilms. The discovery of specific time points and bacteria was of great value in clarifying the pathogenesis of periodontal disease and in seeking targets for prevention and treatment.


Assuntos
Gengivite , Doenças Periodontais , Periodontite , Humanos , Periodontite/microbiologia , Gengivite/microbiologia , Bactérias/genética
12.
Drug Deliv ; 28(1): 873-883, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33960250

RESUMO

The aim of this investigation was to develop an etomidate intravenous lipid emulsion (ETM-ILE) and evaluate its properties in vitro and in vivo. Etomidate (ETM) is a hydrophobic drug, and organic solvents must be added to an etomidate injectable solution (ETM-SOL) to aid dissolution, that causes various adverse reactions on injection. Lipid emulsions are a novel drug formulation that can improve drug loading and reduce adverse reactions. ETM-ILE was prepared using high-pressure homogenization. Univariate experiments were performed to select key conditions and variables. The proportion of oil, egg lecithin, and poloxamer 188 (F68) served as variables for the optimization of the ETM-ILE formulation by central composite design response surface methodology. The optimized formulation had the following characteristics: particle size, 168.0 ± 0.3 nm; polydispersity index, 0.108 ± 0.028; zeta potential, -36.4 ± 0.2 mV; drug loading, 2.00 ± 0.01 mg/mL; encapsulation efficiency, 97.65% ± 0.16%; osmotic pressure, 292 ± 2 mOsmol/kg and pH value, 7.63 ± 0.07. Transmission electron microscopy images showed that the particles were spherical or spheroidal, with a diameter of approximately 200 nm. The stability study suggested that ETM-ILE could store at 4 ± 2 °C or 25 ± 2 °C for 12 months. Safety tests showed that ETM-ILE did not cause hemolysis or serious vascular irritation. The results of the pharmacokinetic study found that ETM-ILE was bioequivalent to ETM-SOL. However, a higher concentration of ETM was attained in the liver, spleen, and lungs after administration of ETM-ILE than after administration of ETM-SOL. This study found that ETM-ILE had great potential for clinical applications.


Assuntos
Anestésicos Intravenosos/administração & dosagem , Anestésicos Intravenosos/farmacocinética , Etomidato/administração & dosagem , Etomidato/farmacocinética , Emulsões Gordurosas Intravenosas/química , Anestésicos Intravenosos/farmacologia , Animais , Química Farmacêutica , Estabilidade de Medicamentos , Etomidato/farmacologia , Concentração de Íons de Hidrogênio , Lecitinas/química , Masculino , Tamanho da Partícula , Poloxâmero/química , Coelhos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Óleo de Soja/química , Propriedades de Superfície
13.
Front Immunol ; 12: 621935, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912154

RESUMO

We compared the effectiveness and safety of pegylated granulocyte colony-stimulating factor (peg-G-CSF) vs. non-peg-G-CSF for hematopoietic stem cell mobilization in allogeneic hematopoietic stem cell transplantation in a real-world setting. We included 136 consecutive healthy donors treated with non-peg-G-CSF (n = 53) or peg-G-CSF (n = 83), and 125 consecutive recipients (n = 42 and 83, respectively) in this study. All harvesting was completed successfully. No significant difference in leukapheresis number and adverse events frequency was observed, nor were there severe adverse events leading to discontinuation of mobilization. The leukapheresis products mobilized by peg-G-CSF had higher total nucleated cells (p < 0.001), monocytic myeloid-derived suppressor cells (p < 0.001), granulocytic myeloid-derived suppressor cells (p = 0.004) and B cells (p = 0.019). CD34+ cells and other lymphocyte subsets (T cells, regulatory T cells, natural killer [NK] cells, etc.) were similar in both apheresis products. Patients who received grafts mobilized by peg-G-CSF exhibited a lower incidence of grade III-IV acute graft-versus-host disease (p = 0.001). The 1-year cumulative incidence of chronic graft-versus-host disease and relapse, 1-year probability of graft-versus-host disease-free relapse-free survival, and overall survival did not differ significantly between subgroups. Our results suggest that collecting allogeneic stem cells after the administration of peg-G-CSF is feasible and safe. Peg-G-CSF mobilized grafts may reduce severe acute graft-versus-host disease compared with non-peg-G-CSF mobilized grafts after allogeneic stem cell transplantation. The beneficial effects of a peg-G-CSF graft might be mediated by increased numbers of monocytic myeloid-derived suppressor cells.


Assuntos
Aloenxertos/imunologia , Doença Enxerto-Hospedeiro/imunologia , Fator Estimulador de Colônias de Granulócitos/metabolismo , Transplante de Células-Tronco Hematopoéticas , Células Supressoras Mieloides/imunologia , Polietilenoglicóis/metabolismo , Doença Aguda , Adolescente , Adulto , Criança , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/mortalidade , Mobilização de Células-Tronco Hematopoéticas , Humanos , Leucaférese , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Índice de Gravidade de Doença , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
14.
Sci Robot ; 5(45)2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-33022630

RESUMO

Batteries with conformal shape and multiple functionalities could provide new degrees of freedom in the design of robotic devices. For example, the ability to provide both load bearing and energy storage can increase the payload and extend the operational range for robots. However, realizing these kinds of structural power devices requires the development of materials with suitable mechanical and ion transport properties. Here, we report biomimetic aramid nanofibers-based composites with cartilage-like nanoscale morphology that display an unusual combination of mechanical and ion transport properties. Ion-conducting membranes from these aramid nanofiber composites enable pliable zinc-air batteries with cyclic performance exceeding 100 hours that can also serve as protective covers in various robots including soft and flexible miniaturized robots. The unique properties of the aramid ion conductors are attributed to the percolating network architecture of nanofibers with high connectivity and strong nanoscale filaments designed using a graph theory of composite architecture when the continuous aramid filaments are denoted as edges and intersections are denoted as nodes. The total capacity of these body-integrated structural batteries is 72 times greater compared with a stand-alone Li-ion battery with the same volume. These materials and their graph theory description enable a new generation of robotic devices, body prosthetics, and flexible and soft robotics with nature-inspired distributed energy storage.


Assuntos
Materiais Biomiméticos , Fontes de Energia Elétrica , Robótica/instrumentação , Biomimética/instrumentação , Biomimética/estatística & dados numéricos , Condutividade Elétrica , Técnicas Eletroquímicas , Desenho de Equipamento , Fractais , Humanos , Lítio , Microscopia Eletrônica de Varredura , Nanofibras/química , Nanofibras/ultraestrutura , Polímeros/química , Robótica/estatística & dados numéricos , Zinco
15.
Biomater Sci ; 7(11): 4790-4799, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31524909

RESUMO

The size effect of mesoporous organosilica nanoparticles (MONs) on tumor penetration and accumulation remains poorly understood, which strongly affects the tumor therapeutic efficacy. Herein, four different-sized thioether-bridged MONs (20, 40, 60, and 100 nm) are synthesized; all the MONs have a spherical morphology, excellent dispersity, similar surface charge, uniform mesopores (3.2-3.5 nm), and large surface areas (709-1353 m2·g-1). Hematology and histopathology analyses demonstrate that the four MONs do not cause pathological changes in mice even at a dose of 20 mg kg-1 for 30 d. The penetration depth of the MONs for multicellular spheroids (MCSs) decreases with increasing particle sizes, and the 20 nm MONs are uniformly distributed in the MCSs at a depth of 60 µm, while the larger MONs are mainly restricted to peripheral areas. In vivo experiments show that the 40 nm MONs possess the longest mean residence times, leading to their highest accumulation in blood and tumors. However, the 20 nm MONs reach the deepest penetration depth of 1230 µm for xenograft tumors. In contrast, the penetration depths of 40, 60, and 100 nm MONs are 783, 105, and 40 µm, respectively. Overall, this work provides an important guideline for the rational design of nanoplatforms for tumor treatment.


Assuntos
Materiais Biocompatíveis/farmacocinética , Neoplasias da Mama/química , Nanopartículas/química , Compostos de Organossilício/farmacocinética , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Neoplasias da Mama/diagnóstico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Feminino , Humanos , Injeções Intravenosas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos , Camundongos Nus , Compostos de Organossilício/síntese química , Compostos de Organossilício/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Distribuição Tecidual
16.
Biosens Bioelectron ; 23(8): 1278-84, 2008 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-18182283

RESUMO

In order to protect implanted glucose sensors from biofouling, novel hydrogels (146-217% water by mass) were developed based on a copolymer of hydroxyethyl methacrylate (HEMA) and 2,3-dihydroxypropyl methacrylate (DHPMA). The porosity and mechanical properties of the hydrogels were improved using N-vinyl-2-pyrrolidinone (VP) and ethyleneglycol dimethacrylate (EGDMA). The results of SEM and DSC FT-IT analyses showed that the hydrogel (VP30) produced from a monomeric mixture of 34.5% HEMA, 34.5% DHPMA, 30% VP and 1% EDGMA (mol%) had an excellent pore structure, high water content at swelling equilibrium (W eq=166% by mass) and acceptable mechanical properties. Two kinds of VP30-coated sensors, Pt/GOx/VP30 and Pt/GOx/epoxy-polyurethane (EPU)/VP30 sensors were examined in glucose solutions during a period of 4 weeks. The Pt/GOx/VP30 sensors produced large response currents but the response linearity was poor. Therefore, further studies were focused on the Pt/GOx/EPU/VP30 sensors. With a diffusion-limiting epoxy-polyurethane membrane, the linearity was improved (2-30 mM) and the response time was within 5 min. Eight Pt/GOx/EPU/VP30 sensors were subcutaneously implanted in rats and tested once per week over 4 weeks. All of the implanted sensors kept functioning for at least 21 days and 3 out of 8 sensors still functioned at day 28. Histology revealed that the fibrous capsules surrounding hydrogel-coated sensors were thinner than those surrounding Pt/GOx/EPU sensors after 28 days of implantation.


Assuntos
Técnicas Biossensoriais/instrumentação , Materiais Revestidos Biocompatíveis/química , Eletroquímica/instrumentação , Glucose/análise , Hidrogéis/química , Microeletrodos , Próteses e Implantes , Animais , Técnicas Biossensoriais/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Ratos , Sensibilidade e Especificidade
17.
Zhongguo Zhong Yao Za Zhi ; 33(6): 628-31, 2008 Mar.
Artigo em Zh | MEDLINE | ID: mdl-18590186

RESUMO

OBJECTIVE: To study scutellaria thermosensitive gel in situ. METHOD: The phase transition temperature of gel with various concentration polymer solutions was studied by using stirring method and the viscosity of gel was monitored under different temperatures. Eye irritation experiments were performed with rabbit. The duration of residence time in rabbit eyes of scutellaria thermosensitive gel was observed with 2% fluorescein. RESULT: 20% poloxmar407 and 10% poloxmar 188 were suitable to scutellaria thermosen-sitive gel in situ. The results suggested that the scutellaria thermosensitive gel in situ based on poloxmar were nonirritant and retention time on the surface of eye was (150 +/- 8) min. CONCLUSION: The scutellaria thermosensitive gel in situ forms gel in eye and has longer release time than that of eye drops.


Assuntos
Scutellaria/química , Temperatura de Transição , Animais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/metabolismo , Medicamentos de Ervas Chinesas/toxicidade , Olho/efeitos dos fármacos , Feminino , Géis , Masculino , Soluções Oftálmicas/metabolismo , Poloxâmero/química , Coelhos , Scutellaria/metabolismo , Scutellaria/toxicidade , Sensibilidade e Especificidade , Fatores de Tempo
18.
J Biomater Sci Polym Ed ; 29(13): 1595-1611, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29764301

RESUMO

In this study, we develop an osteopromotive polyetheretherketone (PEEK) implant decorated with silk fibroin and bone forming peptide, in which the surface of bioinert PEEK implant is firstly sulfonated to form a three-dimensional, porous topography and then is functionalized with silk fibroin via spin-coating process and peptide decoration. The bio-test results show that cells on the functional bioinert implants exhibit better cell adhesion, proliferation and spreading, when compared with the uncoated ones. Moreover, the peptide-decorated silk fibroin coatings have ability to hasten the osteogenic differentiation and maturation of osteoblast-like cells. Our findings show the potential of the functional PEEK implants with superior bioactivity and osteoinductive property in orthopedics and dentistry. Besides, the facile, bioinspired, osteopromotive modification strategy can be used in other orthopedic and dental implants, such as titanium, zirconium dioxide.


Assuntos
Fibroínas/química , Osteoblastos/química , Peptídeos/química , Próteses e Implantes , Seda/química , Benzofenonas , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Humanos , Cetonas/química , Cetonas/metabolismo , Osteogênese , Polietilenoglicóis/química , Polietilenoglicóis/metabolismo , Polímeros , Porosidade , Propriedades de Superfície , Engenharia Tecidual/métodos , Alicerces Teciduais/química
19.
Adv Mater ; 30(10)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29333658

RESUMO

Nanomedicine has shown unprecedented potential for cancer theranostics. Nucleic acid (e.g., DNA and RNA) nanomedicines are of particular interest for combination therapy with chemotherapeutics. However, current nanotechnologies to construct such nucleic acid nanomedicines, which rely on chemical conjugation or physical complexation of nucleic acids with chemotherapeutics, have restrained their clinical translation due to limitations such as low drug loading efficiency and poor biostability. Herein, in situ rolling circle transcription (RCT) is applied to synthesize short hairpin RNA (shRNA) on amphiphilic DNA-polylactide (PLA) micelles. Core-shell PLA@poly-shRNA structures that codeliver a high payload of doxorubicin (Dox) and multidrug resistance protein 1 (MDR1) targeted shRNA for MDR breast cancer (BC) therapy are developed. DNA-PLA conjugates are first synthesized, which then self-assemble into amphiphilic DNA-PLA micelles; next, using the conjugated DNA as a promoter, poly-shRNA is synthesized on DNA-PLA micelles via RCT, generating PLA@poly-shRNA microflowers; and finally, microflowers are electrostatically condensed into nanoparticles using biocompatible and multifunctional poly(ethylene glycol)-grafted polypeptides (PPT-g-PEG). These PLA@poly-shRNA@PPT-g-PEG nanoparticles are efficiently delivered into MDR breast cancer cells and accumulated in xenograft tumors, leading to MDR1 silencing, intracellular Dox accumulation, potentiated apoptosis, and enhanced tumor therapeutic efficacy. Overall, this nanomedicine platform is promising to codeliver anticancer nucleic acid therapeutics and chemotherapeutics.


Assuntos
Nanopartículas , Neoplasias da Mama , DNA , Doxorrubicina , Humanos , Micelas , Poliésteres , Polietilenoglicóis , RNA Interferente Pequeno
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(11): 1531-1535, 2016 Nov 20.
Artigo em Zh | MEDLINE | ID: mdl-27881345

RESUMO

OBJECTIVE: To extract and identify semen-derived exosome using PEG6000. METHODS: Exosomes were extracted from semen specimens from 6 healthy volunteers with step-by-step centrifugations and ultracentrifugation prior to 8% PEG6000 enrichment. The extracted exosomes were characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and Western blotting. RESULTS: The pellets obtained were round or elliptic membrane vesicles 30 to 150 nm in diameter with intact double membranes and contained low electron density material. The pellets expressed CD63, ALIX and TSG101 molecules but not calnexin that was expressed in sperm cells. CONCLUSION: The PEG6000-based method for extraction of exosomes from semen samples facilitates future studies of seminal exosomes.


Assuntos
Exossomos/química , Sêmen/química , Western Blotting , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ciclo Celular/metabolismo , Centrifugação , Proteínas de Ligação a DNA/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Nanopartículas , Polietilenoglicóis , Espermatozoides , Tetraspanina 30/metabolismo , Fatores de Transcrição/metabolismo , Ultracentrifugação
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