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1.
Anal Methods ; 13(45): 5487-5492, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34738609

RESUMO

The Fe3O4@Au nanostars, whose anisotropic shape couples the plasmons focused on the magnetic core with the branches of the gold shell, hold promise for surface enhanced Raman spectroscopy (SERS) applications. Assembly of monodisperse Fe3O4@Au nanostars induced by a magnetic field could lead to highly ordered superstructures, providing distinctive SERS activity. In this study, a simplified fabrication technique was developed to assemble Fe3O4@Au nanostars on the inner walls of a glass capillary into a highly sensitive, reproducible and recyclable SERS active glass capillary under controlled magnetic alignment. The strong dipole-dipole interactions between the neighboring nanoparticles lead to a close-packed pattern as an energetically favorable configuration. The magnetic dipolar interaction between the particles can be further tuned by the controlled anisotropic shape of the gold shell. The interparticle plasmon couplings and lightning rod effects of the Fe3O4@Au nanostars contributed to Raman enhancement. Based on the capillary action, capillaries can act as a microreactor for the sampling tools. We further demonstrate SERS-based colorant detection in the capillary which the target molecule can easily detect by simple adsorption of the colorants by capillary action. The Fe3O4@Au nanostars in the capillary with a long shelf life, high sensitivity and low cost promote the application of SERS technology in widespread fields.

2.
Cardiovasc Res ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609482

RESUMO

AIMS: Remdesivir is a prodrug of an adenosine triphosphate analogue and is currently the only drug formally approved for the treatment of hospitalised COVID-19 patients. Nucleoside/nucleotide analogues have been shown to induce mitochondrial damage and cardiotoxicity, and this may be exacerbated by hypoxia, which frequently occurs in severe COVID-19 patients. Although there have been few reports of adverse cardiovascular events associated with remdesivir, clinical data are limited. Here, we investigated whether remdesivir induced cardiotoxicity using an in vitro human cardiac model. METHODS AND RESULTS: Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were exposed to remdesivir under normoxic and hypoxic conditions to simulate mild and severe COVID-19 respectively. Remdesivir induced mitochondrial fragmentation, reduced redox potential and suppressed mitochondrial respiration at levels below the estimated plasma concentration under both normoxic and hypoxic conditions. Non-mitochondrial damage such as electrophysiological alterations and sarcomere disarray were also observed. Importantly, some of these changes persisted after the cessation of treatment, culminating in increased cell death. Mechanistically, we found that inhibition of DRP1, a regulator of mitochondrial fission, ameliorated the cardiotoxic effects of remdesivir, showing that remdesivir-induced cardiotoxicity was preventable and excessive mitochondrial fission might contribute to this phenotype. CONCLUSIONS: Using an in vitro model, we demonstrated that remdesivir can induce cardiotoxicity in hiPSC-CMs at clinically relevant concentrations. These results reveal previously unknown potential side-effects of remdesivir and highlight the importance of further investigations with in vivo animal models and active clinical monitoring to prevent lasting cardiac damage to patients. TRANSLATIONAL PERSPECTIVE: Adult cardiomyocytes have limited ability to regenerate, thus treatment-induced cardiotoxicity can potentially cause irreparable harm. Remdesivir is currently the only FDA approved treatment for COVID-19 but clinical safety data are limited. Using human pluripotent stem cell-derived cardiomyocytes, we revealed that remdesivir induced persistent mitochondrial and structural abnormalities at clinically relevant concentrations. We advise confirmatory experiments in in vivo animal models, investigations of cardioprotective strategies, and closer patient monitoring such that treatment-induced cardiotoxicity does not contribute to the long term sequelae of COVID-19 patients.

3.
Front Mol Biosci ; 8: 699827, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513920

RESUMO

Angiotensin II (Ang II) plays an important role in regulating various physiological processes. However, little is known about the existence of intracellular Ang II (iAng II), whether iAng II would regulate the automaticity of early differentiating cardiomyocytes, and the underlying mechanism involved. Here, iAng II was detected by immunocytochemistry and ultra-high performance liquid chromatography combined with electrospray ionization triple quadrupole tandem mass spectrometry in mouse embryonic stem cell-derived cardiomyocytes (mESC-CMs) and neonatal rat ventricular myocytes. Expression of AT1R-YFP in mESC-CMs revealed that Ang II type 1 receptors were located on the surface membrane, while immunostaining of Ang II type 2 receptors (AT2R) revealed that AT2R were predominately located on the nucleus and the sarcoplasmic reticulum. While extracellular Ang II increased spontaneous action potentials (APs), dual patch clamping revealed that intracellular delivery of Ang II or AT2R activator C21 decreased spontaneous APs. Interestingly, iAng II was found to decrease the caffeine-induced increase in spontaneous APs and caffeine-induced calcium release, suggesting that iAng II decreased spontaneous APs via the AT2R- and ryanodine receptor-mediated pathways. This is the first study that provides evidence of the presence and function of iAng II in regulating the automaticity behavior of ESC-CMs and may therefore shed light on the role of iAng II in fate determination.

4.
Cells ; 10(9)2021 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-34572112

RESUMO

Pluripotent stem cells (PSCs) can undergo unlimited self-renewal and can differentiate into all the cell types present in our body, including cardiomyocytes. Therefore, PSCs can be an excellent source of cardiomyocytes for future regenerative medicine and medical research studies. However, cardiomyocytes obtained from PSC differentiation culture are regarded as immature structurally, electrophysiologically, metabolically, and functionally. Mitochondria are organelles responsible for various cellular functions such as energy metabolism, different catabolic and anabolic processes, calcium fluxes, and various signaling pathways. Cells can respond to cellular needs to increase the mitochondrial mass by mitochondrial biogenesis. On the other hand, cells can also degrade mitochondria through mitophagy. Mitochondria are also dynamic organelles that undergo continuous fusion and fission events. In this review, we aim to summarize previous findings on the changes of mitochondrial biogenesis, mitophagy, and mitochondrial dynamics during the maturation of cardiomyocytes. In addition, we intend to summarize whether changes in these processes would affect the maturation of cardiomyocytes. Lastly, we aim to discuss unanswered questions in the field and to provide insights for the possible strategies of enhancing the maturation of PSC-derived cardiomyocytes.


Assuntos
Dinâmica Mitocondrial , Mitofagia , Miócitos Cardíacos/patologia , Biogênese de Organelas , Animais , Humanos
5.
Stem Cell Res Ther ; 12(1): 262, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33941260

RESUMO

BACKGROUND: Biological pacemakers consisting of pluripotent stem cell-derived cardiomyocytes are potentially useful for treating bradycardia. However, tachyarrhythmia caused by derived cardiomyocytes themselves is one of main barriers hampering their clinical translation. An in-depth understanding of the mechanisms underlying the spontaneous action potential (a.k.a. automaticity) might provide potential approaches to solve this problem. The aim of this project is to study the role of canonical transient receptor potential isoform 7 (TRPC7) channels in regulating the automaticity of embryonic stem cell-derived cardiomyocytes (ESC-CMs). METHODS AND RESULTS: By Western blotting, the expression of TRPC7 was found to be increased during the differentiation of mouse ESC-CMs (mESC-CMs). Adenovirus-mediated TRPC7 knockdown decreased while overexpression increased the frequency of Ca2+ transients (CaTs), local Ca2+ releases (LCRs), and action potentials (APs) as detected by confocal microscopy and whole-cell patch-clamping. TRPC7 was found to be positively associated with the activity of ryanodine receptor 2 (RyR2), sarco/endoplasmic reticulum Ca2+-ATPase (SERCA), and sodium-calcium exchanger (NCX) but not hyperpolarization-activated, cyclic nucleotide-gated channel (HCN), and inositol trisphosphate receptor (IP3R). Knockdown or overexpression of TRPC7 did not alter the expression of HCN4, Cav1.3, Cav3.1, Cav3.2, IP3R1, RyR2, and SERCA but positively regulated the phosphorylation of RyR2 at S2814 and phospholamban (PLN) at T17. Moreover, the positive regulation of APs by TRPC7 was Ca2+-dependent, as overexpression of N-terminus of TRPC7 (dominant negative of TRPC7) which diminished the Ca2+ permeability of TRPC7 decreased the AP frequency. CONCLUSIONS: TRPC7 regulates the automaticity of mESC-CMs through two mechanisms. On the one hand, TRPC7 positively regulates the intracellular Ca2+ clock through the regulation of activities of both RyR2 and SERCA; on the other hand, TRPC7 also positively regulates the membrane clock via its influence on NCX activity. Altogether, our study reveals that TRPC7 is a potential drug target to manipulate the action potential firing rate of pluripotent stem cell-derived cardiomyocyte-based biological pacemakers to prevent tachyarrhythmia, a condition that might be encountered after transplantation.


Assuntos
Células-Tronco Embrionárias , Miócitos Cardíacos , Potenciais de Ação , Animais , Cálcio/metabolismo , Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Camundongos , Miócitos Cardíacos/metabolismo , Trocador de Sódio e Cálcio , Canais de Cátion TRPC/genética
8.
Nano Lett ; 20(10): 7304-7312, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32866018

RESUMO

Surface-enhanced Raman scattering (SERS) technique with naturally born analyte identification capability can achieve ultrahigh sensitivity. However, the sensitivity and quantification capability of SERS are assumed to be mutually exclusive. Here, we prohibit the formation of the ultrasensitive SERS sites to achieve a high quantification capability through separating the gold (Au) nanorods from approaching each other with thick metal organic framework (MOF) shells. The sensitivity decrease caused by the absence of the ultrasensitive SERS sites is compensated by the analyte enrichment function of a slippery surface. The porous MOF shell around the Au nanorod only allows analytes smaller than the pore size to approach the Au nanorods and contribute to the SERS spectrum within the complex sample, greatly enhancing the analyte identification capability. Overall, we have demonstrated an integrated SERS platform with analyte enrichment and analyte filtration function, realizing sensitive, quantitative, and size selective analyte identification in complex environments.


Assuntos
Nanopartículas Metálicas , Nanotubos , Filtração , Ouro , Análise Espectral Raman
9.
J Am Heart Assoc ; 9(6): e010240, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32157956

RESUMO

Background Pin2/TRF1-interacting protein, PinX1, was previously identified as a tumor suppressor. Here, we discovered a novel transcript variant of mPinX1 (mouse PinX1), mPinX1t (mouse PinX1t), in embryonic stem cells (ESCs). The aims of this investigation were (1) to detect the presence of mPinX1 and mPinX1t in ESCs and their differentiation derivatives; (2) to investigate the role of mPinX1 and mPinX1t on regulating the characteristics of undifferentiated ESCs and the cardiac differentiation of ESCs; (3) to elucidate the molecular mechanisms of how mPinX1 and mPinX1t regulate the cardiac differentiation of ESCs. Methods and Results By 5' rapid amplification of cDNA ends, 3' rapid amplification of cDNA ends, and polysome fractionation followed by reverse transcription-polymerase chain reaction, mPinX1t transcript was confirmed to be an intact mRNA that is actively translated. Western blot confirmed the existence of mPinX1t protein. Overexpression or knockdown of mPinX1 (both decreased mPinX1t expression) both decreased while overexpression of mPinX1t increased the cardiac differentiation of ESCs. Although both mPinX1 and mPinX1t proteins were found to bind to cardiac transcription factor mRNAs, only mPinX1t protein but not mPinX1 protein was found to bind to nucleoporin 133 protein, a nuclear pore complex component. In addition, mPinX1t-containing cells were found to have a higher cytosol-to-nucleus ratio of cardiac transcription factor mRNAs when compared with that in the control cells. Our data suggested that mPinX1t may positively regulate cardiac differentiation by enhancing export of cardiac transcription factor mRNAs through interacting with nucleoporin 133. Conclusions We discovered a novel transcript variant of mPinX1, the mPinX1t, which positively regulates the cardiac differentiation of ESCs.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular , Células-Tronco Embrionárias Murinas/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Linhagem Celular , Linhagem da Célula , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Morfogênese , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Isoformas de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Genética , Proteínas Supressoras de Tumor/genética
10.
Nanotechnology ; 31(13): 135401, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-31816611

RESUMO

Developing low cost and highly robust electrocatalysts for oxygen evolution reaction, hydrogen evolution reaction (HER), and oxygen reduction reaction (ORR) is of great importance for the efficient conversion of sustainable energy sources. Herein, we report a facile pyrolysis strategy for the controllable synthesis of NiCo@NiS/S-CNTs with NiCo@NiS nanoparticles anchored on sulfur-doped carbon nanotubes (CNTs). The obtained NiCo@NiS/S-CNT electrocatalyst exhibits excellent dual-functional catalytic activities under an alkaline condition, an ORR performance with an onset potential of -30 mV, and a half-wave potential of -150 mV (versus Ag/AgCl) while the overpotential for the HER is -1.16 V (versus Ag/AgCl) at a current density of 10 mA cm-2. It was found that the incorporation of sulfur can regulate the electronic structure of CNTs to accelerate the electron transfer performance and generate new catalytic sites, thus contributing to greatly enhancing both the activity and stability of the catalytic process. This work provides a promising way for the rational design of efficient and robust catalysts for sustainable energy conversion.

11.
J Phys Chem Lett ; 10(21): 6484-6491, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588754

RESUMO

Surface-enhanced Raman scattering (SERS) substrates capable of working under laser excitation in a broad wavelength range are highly desirable in diverse application fields. Here, we demonstrate that the bioinspired Ag brochosomes, hollow microscale particles with submicroscale pits, have broadband and omnidirectional SERS performance. The SERS performance of the Ag brochosomes under near-infrared laser excitation makes them promising for applications in biosensing fields, such as the sensitive detection of Staphylococcus aureus bacteria and bovine hemoglobin protein. Additionally, the SERS intensity was insensitive to the incident angle of the laser beam, resulting from the spherical structure of the Ag brochosomes. The omnidirectional SERS performance makes the Ag brochosomes have application potential for in-the-field analysis using a hand-held Raman spectrometer for which it is difficult to accurately control the laser beam normal to the SERS substrates. Overall, the broadband and omnidirectional brochosome SERS substrates will find applications in diverse fields, particularly in biomedicine and in-the-field analysis.

12.
J Mol Med (Berl) ; 97(6): 829-844, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30944935

RESUMO

Nature of exosome-secreting cells determines exosome content and function. ALIX, involved in exosome biogenesis, promotes cell degeneration. Here, ALIX was knocked out (iPSC-ALIX-/-) and overexpressed (iPSC-ALIX3+) in induced pluripotent stem cells (iPSCs) using CRISPR-Cas9 and lentiviral transduction, respectively, and the secreted exosomes were analyzed. Exosomes from iPSC-ALIX-/- (exosome-KO), iPSC-ALIX3+ (exosome-over), and their corresponding controls contained 176, 529, 431, and 351 proteins, respectively. Exosome-over showed increased protein levels, while exosome-KO contained fewer protein types without differing in total protein content. ALIX knockout did not affect exosome uptake by endothelial cells. Exosome-over more effectively promoted cell viability than exosome-GFP, in a dose-dependent manner. All exosomes were protective for endothelial cells injured by hydrogen peroxide or cisplatin, as demonstrated by promotion of cell viability, horizontal migration, angiogenic sprouting from aortic rings, and formation of capillary-like structures, inhibition of apoptosis, and maintenance of permeability of endothelial monolayer, although exosome-over and exosome-KO had stronger and weaker effects, respectively. SNX2 was important for ALIX-mediated exosomal function. Beneficial functions of the exosomes were independent of experimental models, targeted cell types, causes of injury, exosome-producing iPSC passages, clones of ALIX knockout, and transfection batches of ALIX overexpression. Thus, we present a novel strategy to manipulate iPSCs for production of exosomes with beneficial ALIX-regulated protein composition for varied exosome functions. KEY MESSAGES: ALIX knockout and overexpression regulate protein profile in iPSC-derived exosome. ALIX knockout decreases therapeutic function of iPSC-derived exosomes. ALIX overexpression increases therapeutic function of iPSC-derived exosomes. Manipulating iPSCs can produce exosomes with more beneficial protein content.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ciclo Celular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Exossomos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Substâncias Protetoras/metabolismo , Animais , Aorta/efeitos dos fármacos , Sequência de Bases , Proteínas de Ligação ao Cálcio/deficiência , Proteínas de Ciclo Celular/deficiência , Movimento Celular/efeitos dos fármacos , Cisplatino/farmacologia , Complexos Endossomais de Distribuição Requeridos para Transporte/deficiência , Exossomos/efeitos dos fármacos , Exossomos/ultraestrutura , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Camundongos , Neovascularização Fisiológica/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Nexinas de Classificação/metabolismo
13.
Ecotoxicol Environ Saf ; 168: 378-387, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30396134

RESUMO

A growing number of epidemiological surveys show that PM2.5 is an important promoter for the cardiovascular dysfunction induced by atmospheric pollution. PM2.5 is a complex mixture of solid and liquid airborne particles and its components determine the health risk of PM2.5to a great extent. However, the individual cardiotoxicities of different PM2.5 fractions are still unclear, especially in the cellular level. Here we used the neonatal rat cardiomyocytes (NRCMs) to evaluate the cardiac toxicity of PM2.5 exposure. The cytotoxicities of Total-PM2.5, water soluble components of PM2.5 (WS-PM2.5) and water insoluble components of PM2.5 (WIS-PM2.5), which include the cell viability, cell membrane damage, reactive oxygen species (ROS) generation, were examined with NRCMs in vitro. The results indicated that Total-PM2.5 or WIS-PM2.5 exposure significantly decreased the cell viability, induced the cell membrane damage and increased the ROS level in NRCMs at concentrations above 50 µg/mL. However, WS-PM2.5 exposure could induce the cytotoxicity on NRCMs until the concentration of WS-PM2.5 was raised to a higher concentration (75 µg/mL). Furthermore, the DNA damage was detected in NRCMs after 48 h of exposure with Total-PM2.5, WS-PM2.5 or WIS-PM2.5 (75 µg/mL) and the adverse effects on mitochondrial function and action potentials of NRCMs were detected only both in the Total-PM2.5 and WIS-PM2.5 treatment group. In summary, our project not only estimates the risk of PM2.5 on cardiac cells but also reveal that Total-PM2.5 and WIS-PM2.5 exposure were predominantly associated with the functional cardiotoxicities in NRCMs.


Assuntos
Cardiotoxinas/toxicidade , Miócitos Cardíacos/efeitos dos fármacos , Material Particulado/toxicidade , Animais , Animais Recém-Nascidos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
14.
Nanotechnology ; 29(41): 414001, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30052528

RESUMO

Surface-enhanced Raman scattering (SERS) has been recognized as a promising sensing technique in biomedical/biosensing applications and analytical chemistry. Silver (Ag) nanostructures have the strongest SERS enhancement, but suffer from severe enhancement degradation induced by oxidation. Here, we introduce electrochemical reduction of silver oxide to produce Ag SERS substrates on request to partially circumvent the SERS enhancement degradation problem of Ag SERS substrates. Silver oxide nanostructures were first prepared in pure silver citrate aqueous solutions with controllable morphologies depending on the electrodeposition parameters. The transition process from silver oxide to Ag was investigated by density functional theory calculations. Based on the understanding of the transition mechanism, heating treatment, applying reducing agent, and electrochemical reduction were adopted to transform silver oxide to Ag. Notably, no organic agents were introduced neither in the electrodeposition of silver oxide nor electrochemical transformation of silver oxide to Ag. The electrochemical reduction strategy could produce Ag SERS substrates with a 'clean' surface with outstanding SERS performance in a simple as well as cost and time effective manner. Ag SERS substrates can be used in biomedical/biosensing fields. The approach through electrochemical reduction of silver oxide to generate Ag SERS substrate may push forward practical application process of Ag SERS substrates.

15.
Langmuir ; 34(25): 7404-7415, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29874461

RESUMO

A series of naphthalimide derivative gelators (G-o, G-m, and G-p) with three molecular isomers as their terminal groups were designed and synthesized. Only G-m and G-p could form stable organogels in some solvents including methanol, acetonitrile, n-hexane, toluene, ethanol, DMSO, DMF, and mixed solvents of acetonitrile/H2O (1/1, v/v). The different self-assembly structures were obtained from the self-assembly process of G-o, G-m, and G-p such as structures like a Chinese chestnut formed by irregular micrometer pieces, microbelts, and microbelt structures mingled with the bird's nest structures which exhibited different surface hydrophobicity with water contact angles of 121-139° due to their different intermolecular noncovalent interactions. To our surprise, G-p acetonitrile solution emitted 492 nm light with a red-shift of 72 nm compared with that emitted from G-o and G-m acetonitrile solution under 350 nm light excitation. Three gelators showed different detection abilities toward metal ions. G-o did not have any ability for sensitive and selective detection toward any ion. In contrast, G-m and G-p could sensitively and selectively detect Hg2+ and Fe3+. The detection limits for Fe3+ and Hg 2+ by G-m were 4.76 × 10-5 M and 7.01 × 10-6 M with the corresponding association constants ( K) of 1.64 × 104 and 3.79 × 104 M-1, respectively. The detection limits for Fe3+ and Hg2+ by G-p were 3.26 × 10-5 and 1.77 × 10-6 M with the corresponding K of 1.44 × 105 and 1.99 × 104 M-1, respectively. More interestingly, the back-titration of SCN- could distinguish Hg2+ from Fe3+. At the same time, xerogels G-m and G-p also exhibited responsiveness toward Fe3+ and Hg2+ through fluorescence changes. The photophysical properties, gel formation, hierarchical structures, surface wettability, and their function in this self-assembly system could be tuned through the molecular isomer effect. This work provides a new research paradigm for molecular isomer tuned supramolecular self-assembly materials from noncovalent interaction to molecular function.

16.
Exp Ther Med ; 15(6): 4665-4670, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29805484

RESUMO

Acute respiratory distress syndrome (ARDS) is a disease that seriously threatens human life and health. The aim of the study was to investigate the effects of ulinastatin combined with mechanical ventilation on oxygen metabolism, inflammation and stress response, as well as the antioxidant capacity of ARDS. Eighty patients with ARDS treated in Yiwu Central Hospital from January, 2015 to December, 2016 were enrolled in the present study and divided into the observation (n=40) and control (n=40) groups, using a random number table. The control group was treated with mechanical ventilation, while the observation group, based on treatment of the control group, was treated with ulinastatin for 14 consecutive days as one course of treatment. The changes in the relevant indexes of oxygen metabolism, lung function, time of ventilator treatment, total hospital stay, and St. George's Respiratory Questionnaire (SGRQ) score of the two groups after intervention were compared, and the changes in inflammatory cytokine levels, dopamine receptor-related hormone levels, superoxide dismutase (SOD), malondialdehyde (MDA) and total antioxidant capacity of the two groups before intervention and at 1 and 4 weeks after intervention were compared. After intervention, the arterial blood lactate in the observation group was significantly lower than that in the control group (P<0.05), the oxygen uptake rate was significantly higher than that in the control group (P<0.05) and the arterial oxygen content was significantly higher than that in the control group (P<0.05). In the lung function indexes, the FEV1 and FEV1/FVC levels in the observation group were smaller than those in the control group (P<0.05), the duration of ventilator treatment was significantly shorter than that in the control group (P<0.05), and the hospital stay was significantly less than that in the control group (P<0.05). Prior to intervention, SGRQ scores in the two groups were not statistically significant (P>0.05). At 1 and 4 weeks after intervention, the SGRQ scores of the observation group were significantly increased to those of the control group (P<0.05). The tumor levels of necrosis factor-α (TNF-α), interleukin-6 (IL-6) and CRP were significantly lower than those of the control group (P<0.05). The levels of adrenaline and norepinephrine were significantly lower than those of the control group (P<0.05). The levels of MDA, SOD and the total antioxidant capacity were significantly increased to those of control group (P<0.05). The application of ulinastatin combined with mechanical ventilation in ARDS patients is of great significance in improving the oxygen delivery-consumption balance of body, increasing the lung function, reducing the inflammatory and stress response, and improving the antioxidant capacity.

17.
Exp Ther Med ; 15(6): 4791-4797, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29805497

RESUMO

Exosomes are a family of extracellular vesicles that are secreted from almost all types of cells and are associated with cell-to-cell communication. The present study was performed to investigate the effects of human induced pluripotent stem cell-derived exosomes (hiPSC-exo) on cell viability, capillary-like structure formation and senescence in endothelial cells exposed to high glucose. Exosomes were isolated from the conditional medium of hiPSCs and confirmed by transmission electron microscopy, nanoparticle tracking analysis and western blot analysis using Alix and cluster of differentiation-63 as markers. hiPSC-exo were labeled with PKH26 for tracking, and it was determined that spherical exosomes, with a typical cup-shape, were absorbed by human umbilical vascular endothelial cells (HUVECs). Cultured HUVECs were treated with high glucose (33 mM) with or without hiPSC-exo (20 µg/ml) for 48 h, and cell viability, capillary tube formation and senescence were assessed. When exposed to high glucose, viability and tube formation in HUVECs was significantly reduced (P<0.0001), whereas the proportion of senescent cells was higher compared with that in control HUVECs (P<0.0001). Furthermore, hiPSC-exo restored cell viability and capillary-like structure formation, and reduced senescence in HUVECs exposed to high glucose (P<0.0001). However, hiPSC-exo had minimal effects on normal HUVECs. These findings suggest that stem cell-derived exosomes are able to promote cell proliferation, enhance capillary-like structure formation and reduce senescence in endothelial cells exposed to high glucose.

18.
Langmuir ; 33(31): 7788-7798, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28718285

RESUMO

Two simple and novel gelators (G-P with pyridine and G-B with benzene) with different C-4 substitution groups on naphthalimide derivatives have been designed and characterized. Two gelators could form organogels in some solvents or mixed solvents. The self-assembly processes of G-P in a mixed solvent of acetonitrile/H2O (1/1, v/v) and G-B in acetonitrile were studied by means of electron microscopy and spectroscopy. The organogel of G-P in the mixed solvent of acetonitrile/H2O (1/1, v/v) formed an intertwined fiber network, and its emission spectrum had an obvious blue shift compared with that of solution. By contrast, the organogel of G-B in acetonitrile formed a straight fiber, and its emission had an obvious red shift compared with that of solution. G-P and G-B were employed in detecting nitroaromatic compounds because of their electron-rich property. G-P is more sensitive and selective toward 2,4,6-trinitrophenol (TNP) compared with G-B. The sensing mechanisms were investigated by 1H NMR spectroscopic experiments and theoretical calculations. From these experimental results, it is proposed that electron transfer occurs from the electron-rich G-P molecule to the electron-deficient TNP because of the possibility of complex formation between G-P and TNP. The G-P molecule could detect TNP in water, organic solvent media, as well as using test strips. It is worth mentioning that the organogel G-P can not only detect TNP but also remove TNP from the solution into the organogel system.

19.
Soft Matter ; 13(20): 3802-3811, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28485752

RESUMO

A thiophene-based hybrid organogel system consisting of complex iridium (Ir) and EuCl3·6H2O was designed and synthesized to realize dual responses to volatile acids and organic amine vapors. The photophysical properties and self-assembly of compound 1 and the hybrid organogel were also studied. Compound 1 could gelate some organic solvents and self-assemble into 3D nanofibers in the gels. The stable hybrid organogel 1-Ir-Eu could be obtained after addition of complex Ir and EuCl3·6H2O. FTIR spectral results showed that the hydrogen bond still remained even upon addition of complex Ir, EuCl3·6H2O, NaOH and CF3COOH to organogel 1. Interestingly, the emission properties of the hybrid organogel 1-Ir-Eu could undergo interconversion between cyan light and red light via addition of NaOH and CF3COOH. The emission properties of xerogel film 1-Ir-Eu obtained in the presence of NaOH could also undergo fast and reversible transition in response to volatile acids such as CF3COOH, formic acid, acetic acid, propionic acid and organic amine vapors such as ammonium hydroxide, Et3N, tripropylamine, and ethylenediamine. The emission spectral change of Ir-Eu in the organogel or xerogel in the presence of base and acid demonstrated the formation of a new complex between complex Ir and EuCl3·6H2O. This dual-response process could be repeated many times. Contact angle experiment results further showed the morphology and internal components of the xerogel film surface in the process of response to gaseous CF3COOH and Et3N. This work provides a method for producing multifunctional supramolecular materials for sensing volatile acids and organic amine vapors.

20.
J Colloid Interface Sci ; 494: 170-177, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28157635

RESUMO

A new serial of gelators with two cholesteryl groups based on o-phenylenediamine, m-phenylenediamine and p-phenylenediamine were synthesized, and their organogelation ability was evaluated. We found that G-o could form gels in DMF, DMSO and ethyl acetate, G-m and G-p could only gel DMF and 1,4-dioxane. The organogels were thoroughly characterized using various microscopic techniques including field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), UV-Vis spectrum, FT-IR spectrum and contact angle. The gelation ability, morphology, self-assembly mode and materials surface wettability all could be tuned via isomeride effect in self-assembly system. Interestingly, superhydrophobic surface was formed via the self-assembly of compound G-p in 1,4-dioxane and exhibited very high adsorption capacity for water. This gel system provided new method for modulation self-assembly process in supramolecular field.

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