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1.
Small ; : e2103780, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34643028

RESUMO

Optical imaging in the second near infrared region (NIR-II, 1000-1700 nm) provides higher resolution and deeper penetration depth for accurate and real-time vascular anatomy, blood dynamics, and function information, effectively contributing to the early diagnosis and curative effect assessment of vascular anomalies. Currently, NIR-II optical imaging demonstrates encouraging results including long-term monitoring of vascular injury and regeneration, real-time feedback of blood perfusion, tracking of lymphatic metastases, and imaging-guided surgery. This review summarizes the latest progresses of NIR-II optical imaging for angiography including fluorescence imaging, photoacoustic (PA) imaging, and optical coherence tomography (OCT). The development of current NIR-II fluorescence, PA, and OCT probes (i.e., single-walled carbon nanotubes, quantum dots, rare earth doped nanoparticles, noble metal-based nanostructures, organic dye-based probes, and semiconductor polymer nanoparticles), highlighting probe optimization regarding high brightness, longwave emission, and biocompatibility through chemical modification or nanotechnology, is first introduced. The application of NIR-II probes in angiography based on the classification of peripheral vascular, cerebrovascular, tumor vessel, and cardiovascular, is then reviewed. Major challenges and opportunities in the NIR-II optical imaging for vascular imaging are finally discussed.

2.
Dalton Trans ; 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34668907

RESUMO

From the perspective of human health and environmental safety, the development of hydrostable fluorescent sensors for the detection of heavy metal ions and nitroaromatics is an important but a challenging issue. To this end, a water-stable Zn2+ coordination polymer formulated as {[Zn(H2L)]·2DMF·3H2O}n (ZnCP) was prepared elaborately by a solvothermal method using a multidentate ligand (H4L) with 2,6-pyridine-dicarboxylic acid spaced by para-substituted benzene. Single-crystal analysis shows that the new ZnCP exhibits one-dimensional chain structural features, which further promoted to afford a wrinkled two-dimensional network structure via inter-chain hydrogen bonding. Powder X-ray diffraction and fluorescence measurements show that it can maintain crystallinity and structural integrity under harsh acidic and alkaline conditions with the pH ranging from 4 to 11. Notably, the bright blue-emissive ZnCP showed selective fluorescence quenching effects for Fe3+ and picric acid (PA), which makes it an excellent chemical sensor for Fe3+ and picric acid (PA) with low detection limits of 0.41 and 0.26 µM in water. The recognition mechanism of Fe3+ could be attributed to UV absorption competition and resonance energy transfer in the aid of weak electrostatic interactions, while the recognition mechanism of PA is considered to be a multi-quenching mechanism dominated by absorption competition and PET effects with the assistance of hydrogen bonding. In addition, poly(methyl methacrylate) (PMMA) films doped with ZnCP (ZnCP@PMMA) were developed to provide better sensing performance and portability for practical applications.

3.
Inorg Chem ; 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34694111

RESUMO

To advance the structural development and fully explore the application potential, it is highly desirable but challenging to elucidate the relationship between the structures and properties of ZnII-LnIII heterometallic species. Herein, three types of ZnII-LnIII heterometallic compounds (LnIII = GdIII, TbIII) formulated as [Zn16Ln4L12(µ3-O)4(NO3)12]·8CH3CN (ZnLn-1), [Zn2Ln2L2(NO3)6(H2O)2]·3CH3CN (ZnLn-2), and [Zn4Ln2L8(OAc)12]·xCH3CN (ZnLn-3: for Ln = Gd, x = 5; for Ln = Tb, x = 4) were dictated by common inorganic anions, NO3- and OAc-, with the aid of the multidentate ligand H2L with propane as the central skeleton and 3-methoxysalicylamide and 3-methoxysalicylaldimine as terminal groups. ZnLn-1 features cubic cages with four {Zn4L3} tetrahedral subunits and four Ln3+ centers positioned at the eight vertices alternately when NO3- was introduced into the reaction system exclusively. An attempt to replace NO3- in ZnLn-1 with OAc- partially led to the formation of {Zn2Ln2L2} heterometallic wheels. Meanwhile, ZnLn-3 featuring double-hairpin-like {Zn4Ln2L4} hemicycles that are orthogonal to each other assisted by intermolecular hydrogen bonds was constructed when NO3- in ZnLn-1 was completely replaced by OAc-. Their structural integrity in solution were ascertained by both emission and 1H NMR spectroscopy. Ascribed to the different Zn2+-containing antenna, ZnTb-2 possesses a relatively strong emission characteristic of Tb3+; ZnTb-1 has moderate Tb3+ luminescence, yet an absence of Tb3+ emission is found in ZnTb-3. Such an emission difference could be mainly attributed to the antenna effect directed by distinct structural characteristics induced by anions. The anion-dictated self-assembly strategy presented herein not only offers a facile approach to regulate the coordination mode of H2L to such an extent to obtain diverse structures of ZnII-LnIII heterometallic species but also provides an understanding of how common inorganic anions tune coordination-driven self-assemblies as well as the subsequent luminescence properties.

4.
Mater Sci Eng C Mater Biol Appl ; 128: 112295, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474846

RESUMO

It is of great significance to develop osteoinductive artificial scaffold for bone repair and regeneration. We constructed a biomimetic apatite interface on electrospun polycaprolactone fibers by combining layer-by-layer (LbL) nanocoating with mineralization to fabricate an osteoinductive artificial scaffold. After polydopamine modification, cationic type-І collagen and anionic chondroitin sulfate were sequentially adsorbed on the fiber surface. The fibers coated with the multilayer components served as the precursor matrix to induce apatite deposition. By adjusting the number of the layers and duration of mineralization, the nanoscale morphology of composite fibers was optimized. When ten bilayers of the collagen and chondroitin sulfate were deposited onto the fibers followed by one day-mineralization, the obtained polycaprolactone-apatite composite scaffolds significantly promoted the adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 cells. In a subcutaneous implantation in mice, this composite fiber membrane enhanced in vivo ectopic osteogenesis. Our nano-architectural scaffolds were able to mimic the composition and structure of the bone matrix to a certain extent, holding great potential for bone repair and regeneration.


Assuntos
Sulfatos de Condroitina , Osteogênese , Animais , Regeneração Óssea , Diferenciação Celular , Colágeno , Camundongos , Tecidos Suporte
5.
Zhongguo Zhen Jiu ; 41(9): 1060-2, 2021 Sep 12.
Artigo em Chinês | MEDLINE | ID: mdl-34491659

RESUMO

Bidirectional regulation is one of the key function of acupuncture. The stimulator, mediator and receptor are the basis while the specificity of acupoints and the multi-target regulation of receptors receiving stimulation signals are the essential link of the bidirectional regulation of acupuncture. The possible mechanisms of bidirectional regulation of acupuncture are discussed in 4 aspects, i.e. homeostasis mechanism, stress reaction, central adaptive regulation and autonomic nerve regulation. Knowing the limitations of bidirectional regulation and exploring suitable researchmethods are proposed to be the key points in future researches.


Assuntos
Terapia por Acupuntura , Acupuntura , Pontos de Acupuntura
6.
Trials ; 22(1): 663, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34583756

RESUMO

BACKGROUND: Previous studies had already reported the efficacy of electroacupuncture treatment for idiopathic facial nerve palsy (IFP) in a recovery phase; however, the initial use of electroacupuncture in the acute phase remains controversial. Hence, in the present study, we will add electroacupuncture intervention based on oral prednisone tablets in the acute phase of IFP and compare the clinical effects with simple oral prednisone tablets. Besides, the prognosis and safety will be evaluated. The present study aims to evaluate the clinical efficacy, prognosis, and safety of electroacupuncture combined with oral prednisone tablets in the acute phase of IFP, using surface electromyography (sEMG) to objectively observe the recovery of facial expression muscle function. In addition, the morphological changes of the facial nerve were observed dynamically by magnetic resonance imaging (MRI) in the acute phase to reveal the effect mechanism of this therapy. METHODS: Randomized controlled trials will be conducted in the first teaching hospital of Tianjin University of Traditional Chinese Medicine in China from September 2020 to April 2021. The treatment will be carried out in two phases, including the acute phase and the recovery phase. Eighty IFP patients will be recruited and randomized into two groups with a 1:1 ratio. Subjects in the acute phases of the control group will be given oral prednisone tablets, based on the control group, and subjects of the experimental group will be given electroacupuncture therapy simultaneously in the acute phase. Both groups will be stopped taking prednisone tablets and turn to electroacupuncture therapy in a recovery phase. Patients in the experimental group will receive treatment at least 6 times in the acute phase and both groups will receive treatment 9 times in the recovery phase, and there will be a follow-up period of 15 days after the treatment. The primary outcome is supposed to be related to the changes observed in the Sunnybrook (Toronto) Facial Grading System (SFGS) on the baseline and day 30 after the onset. Secondary outcome measures will include House-Brackmann Facial Nerve Grading System (H-B), measurement of Numerical Rating Scale (NRS), Facial Disability Index scale (FDI, including physical function subscore, FDIP, and social functioning and well-being subscore, FDIS), surface electromyogram (sEMG), and magnetic resonance imaging (MRI). Adverse events will be recorded for safety assessment. DISCUSSION: The results of this trial will allow the present study to compare the difference in efficacy and prognosis between the strategy of combined electroacupuncture in the acute phase and only oral prednisone tablets. The findings from this trial will be published in peer-reviewed journals. TRIAL REGISTRATION: CHICTR ChiCTR2000038472 . Registered on 23 September 2020.


Assuntos
Paralisia de Bell , Eletroacupuntura , Nervo Facial , Humanos , Imageamento por Ressonância Magnética , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
7.
Rev. bras. med. esporte ; 27(3): 319-322, July-Sept. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1288577

RESUMO

ABSTRACT Introduction People need to strengthen their bodies through leisure sports to prevent diseases. Physical fitness exercise is conducive to maintaining a good physical and mental state and establishing a good interpersonal relationship. Exercise can keep people happy. Object According to the actual needs of people's physical fitness exercises, this article uses the correlation analysis method to carry out an empirical analysis on the effect of physical fitness exercises on the quality of life. Method The paper puts forward a model based on indicators combined with correlation analysis by constructing a hypothetical model of the effect of physical fitness exercise. We analyzed the reasons and influencing factors of people participating in physical fitness exercises. Results The influencing indicators of people's participation in sports to improve the quality of life are gender, age, and disposable income. Conclusion People playing sports can enhance the quality and quality of life. Level of evidence II; Therapeutic studies - investigation of treatment results.


RESUMO Introdução As pessoas precisam fortalecer seus corpos por meio de esportes de lazer para prevenir doenças. O exercício de aptidão física contribui para a manutenção de um bom estado físico e mental e para o estabelecimento de um bom relacionamento interpessoal. O exercício pode manter as pessoas felizes. Objetivo De acordo com as reais necessidades de exercícios de aptidão física das pessoas, este artigo utiliza o método de análise de correlação para realizar uma análise empírica sobre o efeito dos exercícios de aptidão física na qualidade de vida. Método O artigo propõe um modelo baseado em indicadores combinados com análise de correlação por meio da construção de um modelo hipotético do efeito do exercício de aptidão física. Analisamos os motivos e fatores que influenciam as pessoas que participam de exercícios de aptidão física. Resultados Os indicadores que influenciam a participação das pessoas no esporte para melhorar a qualidade de vida são gênero, idade e renda disponível. Conclusão Pessoas que praticam esportes podem melhorar a qualidade de vida. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.


RESUMEN Introducción Las personas necesitan fortalecer su cuerpo a través de deportes recreativos para prevenir enfermedades. El ejercicio físico favorece el mantenimiento de un buen estado físico y mental y el establecimiento de una buena relación interpersonal. El ejercicio puede hacer felices a las personas. Objeto De acuerdo con las necesidades reales de los ejercicios de aptitud física de las personas, este artículo utiliza el método de análisis de correlación para realizar un análisis empírico sobre el efecto de los ejercicios de aptitud física en la calidad de vida. Método El trabajo propone un modelo basado en indicadores combinados con análisis de correlación mediante la construcción de un modelo hipotético del efecto del ejercicio físico. Analizamos los motivos y factores de influencia de las personas que realizan ejercicios de acondicionamiento físico. Resultados Los indicadores que influyen en la participación de las personas en el deporte para mejorar la calidad de vida son el género, la edad y la renta disponible. Conclusión las personas que practican deportes pueden mejorar la calidad de vida. Nivel de evidencia II; Estudios terapéuticos: investigación de los resultados del tratamiento.

8.
Adv Sci (Weinh) ; : e2100505, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34414693

RESUMO

The efficacy of cardiac regenerative strategies for myocardial infarction (MI) treatment is greatly limited by the cardiac microenvironment. The combination of reactive oxygen species (ROS) scavenging to suppress the oxidative stress damage and macrophage polarization to regenerative M2 phenotype in the MI microenvironment can be desirable for MI treatment. Herein, melanin nanoparticles (MNPs)/alginate (Alg) hydrogels composed of two marine-derived natural biomaterials, MNPs obtained from cuttlefish ink and alginate extracted from ocean algae, are proposed. Taking advantage of the antioxidant property of MNPs and mechanical support from injectable alginate hydrogels, the MNPs/Alg hydrogel is explored for cardiac repair by regulating the MI microenvironment. The MNPs/Alg hydrogel is found to eliminate ROS against oxidative stress injury of cardiomyocytes. More interestingly, the macrophage polarization to regenerative M2 macrophages can be greatly promoted in the presence of MNPs/Alg hydrogel. An MI rat model is utilized to evaluate the feasibility of the as-prepared MNPs/Alg hydrogel for cardiac repair in vivo. The antioxidant, anti-inflammatory, and proangiogenesis effects of the hydrogel are investigated in detail. The present study opens up a new way to utilize natural biomaterials for MI treatment and allows to rerecognize the great value of natural biomaterials in cardiac repair.

9.
BMC Pulm Med ; 21(1): 259, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372824

RESUMO

BACKGROUND: Tests to identify reversible airflow limitation are important in asthma diagnosis, but they are time-consuming and it may be difficult for patients to cooperate. We aimed to evaluate whether the combination of fractional exhaled nitric oxide (FeNO) and blood eosinophil (B-Eos) can be used to distinguish some asthma patients who could avoid objective tests. METHODS: We conducted a retrospective cohort study on 7463 suspected asthma cases between January 2014 and December 2019 in Chongqing, China, and identified 2349 patients with complete FeNO, B-Eos count, and spirometry data. Asthma was diagnosed by clinicians by the criteria of recurrent respiratory symptoms and a positive bronchial-provocation or bronchodilation test (BPT, BPD). We evaluated the diagnostic accuracy of FeNO or B-Eos alone or both in combination for asthma using receiver operating characteristic (ROC) curve analysis. RESULTS: In this study, 824 patients were diagnosed with asthma. When FeNO and B-Eos counts were used in combination, the area under the ROC curve (AUC) for diagnosing asthma increased slightly (0.768 vs. 0.745 [FeNO] or 0.728 [B-Eos]; both P < 0.001). The odds ratio for having asthma increased progressively with a gradual increase in FeNO or B-Eos count (both P < 0.001; assessed using the Cochran-Armitage trend test). Further analysis of in-series combinations of different threshold values for these biomarkers indicated that moderately elevated biomarker levels (FeNO > 40 ppb and B-Eos > 300 cells/µl) support a diagnosis of asthma because diagnostic specificity was > 95% and the positive likelihood ratio (PLR) was > 10. This conclusion was verified when selecting the 2017-2019 data as the internal validation dataset. CONCLUSION: FeNO or B-Eos count alone is insufficient to accurately diagnose asthma. Patients with moderately elevated biomarkers (FeNO > 40 ppb and B-Eos > 300 cells/µl) could be diagnosed with asthma and avoid objective tests when such tests are not feasible.

10.
J Ethnopharmacol ; 280: 114420, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34271116

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Andrographis paniculata (Burm.f.) Nees, a traditional Chinese herb, has been widely used in various Asian countries as a treatment for upper respiratory tract infections for centuries. AIM OF THE STUDY: Continuous inhalation of fine particulate matter (PM2.5) may induce various respiratory diseases. This study elucidated the protective effect of the effective part of Andrographis paniculata (Burm.f.) Nees (AEP) against PM2.5-induced lung injury and detailed the underlying mechanism. MATERIALS AND METHODS: Male Wistar rats were orally administered 0.5% sodium carboxymethylcellulose (CMC-Na), andrographolide (AG) (200 mg/kg) and AEP (100 mg/kg, 200 mg/kg and 400 mg/kg) once a day for 28 days. The rats were intratracheally instilled with PM2.5 suspension (8 mg/kg) every other day beginning on the 24th day for a total of 3 times. On the 29th day, bronchoalveolar lavage fluid (BALF) was collected to analyze the levels of lactate dehydrogenase (LDH), acid phosphatase (ACP), alkaline phosphatase (AKP), total proteins (TP), tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6). Hematoxylin & eosin staining was conducted to evaluate the pathological changes in the lung tissues. The protein expression of NF-κB p65 in the lung tissues was analyzed by immunohistochemistry staining. Moreover, the nuclear translocation of NF-κB p65 and the phosphorylation of IκBα were analyzed by western blotting. RESULTS: PM2.5 exposure caused lung toxicity, which was characterized by pathological injury and increased levels of LDH, ACP, AKP and TP in BALF. Meanwhile, PM2.5 exposure induced lung inflammatory response, including infiltration of inflammatory cells and increased levels of inflammatory factors, such as TNF-α and IL-6 in BALF. AEP treatment significantly ameliorated the PM2.5-induced lung toxicity and the inflammatory response in rats. Moreover, AEP significantly inhibited the PM2.5-induced upregulation of NF-κB p65 protein expression, phosphorylation of IκBα and nuclear translocation of NF-κB p65 in lung tissue. Compared to AG, AEP exhibited a better ability to alleviate PM2.5-induced pathological damage and decrease the TP level in the BALF. CONCLUSION: AEP could be used to improve PM2.5-induced lung injury by modulating the NF-κB pathway, and multicomponent therapy with traditional Chinese medicine may be more effective than single-drug therapy.

11.
Aging (Albany NY) ; 13(13): 17734-17767, 2021 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-34247148

RESUMO

Limited progress has been made in the treatment of gastric adenocarcinoma (GAC) in recent years, but the potential of immunotherapy in GAC is worthy of consideration. The purpose of this study was to develop a reliable, personalized signature based on immune genes to predict the prognosis of GAC. Here, we identified two groups of patients with significantly different prognoses by performing unsupervised clustering analysis of The Cancer Genome Atlas (TCGA) database based on 881 immune genes. The immune signature was constructed with a training set composed of 350 GAC samples from the TCGA and subsequently validated with 431 samples from GSE84437, 432 samples from GSE26253, and 145 GAC samples from real-time quantitative reverse transcription polymerase chain reaction data. This classification system can also be used to predict prognosis in different clinical subgroups. Further analysis suggested that high-risk patients were characterized by low immune scores, distinctive immune cell proportions, different immune checkpoint profiles, and a low tumor mutational burden. Ultimately, the signature was identified as an independent prognostic factor. In general, the signature can accurately predict recurrence and overall survival in patients with GAC and may serve as a powerful prognostic tool to further optimize cancer immunotherapy.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/imunologia , Imunidade/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/imunologia , Adulto , Idoso , Biomarcadores Tumorais/análise , Análise por Conglomerados , Biologia Computacional , Bases de Dados Genéticas , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imunoterapia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Reação em Cadeia da Polimerase , Medicina de Precisão , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida
12.
Biomaterials ; 274: 120885, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34022740

RESUMO

It is of great significance to develop multifunctional gene carriers to achieve treatments with enhanced therapeutic effects in an inflammation-free manner. In this work, assembled micelles of polysaccharide were utilized for the biomineralization of calcium carbonate to produce one-dimensional Alg-CaCO3 nanoparticles. In order to introduce both functions of mild hyperthermia and gene transfection, polydopamine (PDA) coating was applied to conjugate cationic polymers on the surface of nanoparticles. The resultant ACDP nanohybrids exhibited enhanced performance as gene carriers under near infrared (NIR) light irradiation at a low power density. Meanwhile, the pH-responsive degradation of gene carriers could further promote gene release for better effectiveness. The enhanced gene therapy induces tumor cell apoptosis, which could prevent inflammatory responses. The feasibility of mild hyperthermia-enhanced gene therapy for tumor treatment was investigated in vitro and in vivo. In addition, dual-modal ultrasound (US) and photoacoustic (PA) imaging was also realized to monitor and guide the treatment processes. The current work provides a new avenue for the construction of multifunctional platform to realize cancer therapy with improved therapeutic effectiveness in an inflammation-free manner.


Assuntos
Hipertermia Induzida , Nanopartículas , Animais , Carbonato de Cálcio , Terapia Genética , Calefação , Camundongos , Camundongos Endogâmicos BALB C , Fototerapia
13.
Chest ; 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34023318

RESUMO

BACKGROUND: Systemic corticosteroids for the treatment of COPD exacerbations decrease treatment failure and shorten the length of hospitalization. However, the optimal dose is unclear. RESEARCH QUESTION: Is personalized-dose corticosteroid administered according to a dosing scale more effective than fixed-dose corticosteroid administration in hospitalized patients with COPD with exacerbations? STUDY DESIGN AND METHODS: This was a prospective, randomized, open-label trial. In-hospital patients with COPD with exacerbations were randomly assigned at a 1:1 ratio to either the fixed-dose group (receiving the equivalent of 40 mg of prednisolone) or the personalized-dose group for 5 days. The primary end point was a composite measure of treatment failure that included in-hospital treatment failure and medium-term (postdischarge) failure. Secondary end points were length of stay and cost. RESULTS: A total of 248 patients were randomly assigned to the fixed-dose group (n = 124) or personalized-dose group (n = 124). One patient in each group was not included in the intention-to-treat population because of incorrect initial COPD diagnosis. Failure of therapy occurred in 27.6% in the personalized-dose group, compared with 48.8% in the fixed-dose group (relative risk, 0.40; 95% CI, 0.24-0.68; P = .001). The in-hospital failure of therapy was significantly lower in the personalized-dose group (10.6% vs 24.4%; P = .005), whereas the medium-term failure rate, adverse event rate, hospital length of stay, and costs were similar between the two groups. After treatment failure, a lower additional dose of corticosteroids and a shorter duration of treatment were needed in the personalized-dose group to achieve control of the exacerbation. In the personalized-dose cohort, those receiving 40 mg or less had an average failure rate of 44.4%, compared with 22.9% among those receiving more than 40 mg (P = .027). INTERPRETATION: Personalized dosing of corticosteroids reduces the risk of failure because more patients were provided with a higher initial dose, especially > 60 mg, whereas 40 mg or less was too low in either group. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT02147015; URL: www.clinicaltrials.gov.

14.
Polymers (Basel) ; 13(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802914

RESUMO

Polymer membranes play a vital role in vanadium redox flow batteries (VRFBs), acting as a separator between the two compartments, an electronic insulator for maintaining electrical neutrality of the cell, and an ionic conductor for allowing the transport of ionic charge carriers. It is a major influencer of VRFB performance, but also identified as one of the major factors limiting the large-scale implementation of VRFB technology in energy storage applications due to its cost and durability. In this work, five (5) high-priority characteristics of membranes related to VRFB performance were selected as major considerable factors for membrane screening before in-situ testing. Eight (8) state-of-the-art of commercially available ion exchange membranes (IEMs) were specifically selected, evaluated and compared by a set of ex-situ assessment approaches to determine the possibility of the membranes applied for VRFB. The results recommend perfluorosulfonic acid (PFSA) membranes and hydrocarbon anion exchange membranes (AEMs) as the candidates for further in-situ testing, while one hydrocarbon cation exchange membrane (CEM) is not recommended for VRFB application due to its relatively high VO2+ ion crossover and low mechanical stability during/after the chemical stability test. This work could provide VRFB researchers and industry a valuable reference for selecting the polymer membrane materials before VRFB in-situ testing.

15.
ACS Nano ; 15(4): 7482-7490, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33856198

RESUMO

Infections caused by multidrug resistant bacteria are still a serious threat to human health. It is of great significance to explore effective alternative antibacterial strategies. Herein, carbon-iron oxide nanohybrids with rough surfaces (RCF) are developed for NIR-II light-responsive synergistic antibacterial therapy. RCF with excellent photothermal property and peroxidase-like activity could realize synergistic photothermal therapy (PTT)/chemodynamic therapy (CDT) in the NIR-II biowindow with improved penetration depth and low power density. More importantly, RCF with rough surfaces shows increased bacterial adhesion, thereby benefiting both CDT and PTT through effective interaction between RCF and bacteria. In vitro antibacterial experiments demonstrate a broad-spectrum synergistic antibacterial effect of RCF against Gram-negative Escherichia coli (E. coli), Gram-positive Staphylococcus aureus (S. aureus), and methicillin-resistant Staphylococcus aureus (MRSA). In addition, satisfactory biocompatibility makes RCF a promising antibacterial agent. Notably, the synergistic antibacterial performances in vivo could be achieved employing the rat wound model with MRSA infection. The current study proposes a facile strategy to construct antibacterial agents for practical antibacterial applications by the rational design of both composition and morphology. RCF with low power density NIR-II light responsive synergistic activity holds great potential in the effective treatment of drug-resistant bacterial infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Animais , Antibacterianos/farmacologia , Carbono , Escherichia coli , Compostos Férricos , Ratos
16.
Small ; 17(11): e2006004, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33619841

RESUMO

The unsymmetrical morphology and unique properties of Janus nanoparticles (JNPs) provide superior performances for biomedical applications. In this work, a general and facile strategy is developed to construct a series of symmetrical and unsymmetrical chitosan/gold nanoparticles. Taking advantage of the active motion derived from Janus structure, selective surface functionalization of polysaccharide domain, and photothermal effect of gold nanorods, Janus chitosan/gold nanoparticles (J-Au-CS) are selected as a model system to construct Janus-structured chitosan/gold nanohybrids (J-ACP). Near-infrared (NIR)-responsive J-ACP composed of polycationic chitosan nanospheres and PEGylated gold nanorods hold great potential to realize photoacoustic (PA) imaging-guided complementary photothermal therapy (PTT)/gene therapy for breast cancer. The morphology effect of chitosan/gold nanostructures on enhanced PTT, cellular uptake, and gene transfection is investigated. The feasibility of PA imaging to track the accumulation of J-ACP and guide PTT is also explored. Notably, synergistic therapy is achieved based on PTT-enhanced gene therapy. In addition, the loading function of chitosan/gold nanoparticles for fluorescence imaging is demonstrated. The current work extends the application of JNPs for imaging-guided synergistic cancer therapy and provides flexible candidates with distinct structures for diverse biomedical applications.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanopartículas Multifuncionais , Nanopartículas , Técnicas Fotoacústicas , Linhagem Celular Tumoral , Ouro , Humanos , Fototerapia , Terapia Fototérmica
17.
Adv Healthc Mater ; 10(1): e2001183, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32935932

RESUMO

Nowadays, nucleic acid therapy has become a promising way for the treatment of various malignant diseases. Cyclodextrin (CD)-based nucleic acid delivery systems have attracted widespread attention due to the favorable chemical structures and excellent biological properties of CD. Recently, a variety of CD-based nucleic acid delivery systems has been designed according to the different functions of CD for flexible gene therapies. In this review, the construction strategies and biomedical applications of CD-based nucleic acid delivery systems are mainly focused on. The review begins with an introduction to the synthesis and properties of simple CD-grafted polycations. Thereafter, CD-related supramolecular assemblies based on different guest components are discussed in detail. Finally, different CD-based organic/inorganic nanohybrids and their relevant functions are demonstrated. It is hoped that this brief review will motivate the delicate design of CD-based nucleic acid delivery systems for potential clinical applications.


Assuntos
Ciclodextrinas , Neoplasias , Ácidos Nucleicos , Humanos
18.
J Clin Invest ; 131(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33141760

RESUMO

Oligodendrocytes express low-density lipoprotein receptor (LDLR) to endocytose cholesterol for the maintenance of adulthood myelination. However, the potential role of LDLR in chronic cerebral ischemia-related demyelination remains unclear. We used bilateral carotid artery stenosis (BCAS) to induce sustained cerebral ischemia in mice. This hypoxic-ischemic injury caused a remarkable decrease in oligodendroglial LDLR, with impaired oligodendroglial differentiation and survival. Oligodendroglial cholesterol levels, however, remained unchanged. Mouse miR-344e-3p and the human homolog miR-410-3p, 2 miRNAs directly targeting Ldlr, were identified in experimental and clinical leukoaraiosis and were thus implicated in the LDLR reduction. Lentiviral delivery of LDLR ameliorated demyelination following chronic cerebral ischemia. By contrast, Ldlr-/- mice displayed inadequate myelination in the corpus callosum. Ldlr-/- oligodendrocyte progenitor cells (OPCs) exhibited reduced ability to differentiate and myelinate axons in vitro. Transplantation with Ldlr-/- OPCs could not rescue the BCAS-induced demyelination. Such LDLR-dependent myelin restoration might involve a physical interaction of the Asn-Pro-Val-Tyr (NPVY) motif with the phosphotyrosine binding domain of Shc, which subsequently activated the MEK/ERK pathway. Together, our findings demonstrate that the aberrant oligodendroglial LDLR in chronic cerebral ischemia impairs myelination through intracellular signal transduction. Preservation of oligodendroglial LDLR may provide a promising approach to treat ischemic demyelination.

19.
Membranes (Basel) ; 10(11)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33105596

RESUMO

Melt processing is one of the essential technologies for the mass production of polymer electrolyte membranes (PEM) at low cost. Azoles have been widely used in PEM to improve their conductivity at a relatively low humidity and recently as bifunctional additives in a melt blowing processing for PEM mass production. In this work, we attempted to assess the effect of 1, 2, 4-triazole additive in membranes and in catalyst layers on PEM fuel cell conditioning. Various characterization tools including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and conditioning with constant current were applied to diagnose the temporary electrochemical reaction effect and the permanent performance loss caused by the triazole additives. It was found that triazole additives in membranes could migrate into the catalyst layers and significantly affect the open circuit voltage (OCV) and the conditioning. The effect could be partially or completely removed/cleaned either through longer conditioning time or via CV cycling, which depends on the amount of additives remaining in the membrane. The findings provide valuable scientific insights on the relevance of post treatment steps during membrane production and overcoming fuel cell contamination issues due to residual additive in the membranes and understanding the quality control needed for fuel cell membranes by melt blowing processing.

20.
J Environ Manage ; 272: 111079, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32854885

RESUMO

Faced with severe and growing social inequality among elderly individuals, a more complete understanding of the interconnection between the seasonal migration of the elderly and climate change is clearly needed. This paper tries to clarify the relation between the seasonal migration of the elderly and climate change from a multidimensional perspective. Our study adds to the research on population aging against the background of climate change. This study shows that climate change has a significant impact on regional population aging and that there are significant internal differences between the distribution and scale of the migratory elderly stemming from unequal environmental conditions. Advanced economic conditions and relatively comfortable environments have put some pressure on social endowment services in the three provinces of Northeast China, especially Liaoning Province. With their complex migration mechanism, the fate of the elderly in mainland China is closely intertwined with climatic factors, individual and socioeconomic conditions, traditional cultural backgrounds, etc. A comparatively advanced economy, well-developed endowment resources, and a comfortable environment will help in the development of regional aging resources. Regional inequality and the pursuit of a meaningful life have created different categories of migratory elderly.


Assuntos
Mudança Climática , Idoso , China , Humanos , Fatores Socioeconômicos
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