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1.
Phys Chem Chem Phys ; 26(5): 4455-4465, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38240145

RESUMO

Storage capacity, average open circuit voltage (OCV), diffusion barrier, lattice parameter changes, etc. are key indicators of whether a material would be suitable for use as a Li-ion or non-Li-ion battery (LIB or NLIB) anode. The rapid development of 2D materials over the past few decades has opened up new possibilities for these metrics. Using first-principles calculations, we prove that two 2D materials, TiB4 and SrB8, show excellent performance in terms of the above metrics when used as anodes for LIBs or NLIBs. As detailed, TiB4 has an Li\Na\K\Ca storage capacity of 588 mA h g-1, 588 mA h g-1, 588 mA h g-1, and 1176 mA h g-1, respectively, and SrB8 has an Li\Na\K\Ca storage capacity of 308 mA h g-1, 308 mA h g-1, 462 mA h g-1, and 616 mA h g-1, respectively, and they show good electrical conductivity whether existing Li, Na, K or Ca is adsorbed or not. The diffusion barriers on both surfaces are low, indicating good rate performance. The average OCV is also very low. In particular, the lattice parameters of the two materials change very little during the embedding of Li\Na\K\Ca. For Ti9B36 the corresponding values are about 0.37% (Li), 0.33% (Na), 0.64% (K) and 0.03% (Ca), and for Sr8B64 the corresponding values are about 0.70% (Li), 0.16% (Na), 0.13% (K) and 0.004% (Ca), which imply zero strain-like character and great cycling performance. All the above results show that TiB4 and SrB8 monolayers are very promising Li\Na\K\Ca ion battery anodes.

2.
Small ; 19(35): e2300392, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37127883

RESUMO

Second near infrared (NIR-II, 1000-1700 nm) fluorescence lifetime imaging is a powerful tool for biosensing, anti-counterfeiting, and multiplex imaging. However, the low photoluminescence quantum yield (PLQY) of fluorescence probes in NIR-II region limits its data collecting efficiency and accuracy, especially in multiplex molecular imaging in vivo. To solve this problem, lanthanide-doped nanoparticles (NPs) ß-NaErF4 : 2%Ce@NaYbF4 @NaYF4 with high PLQY and tunable PL lifetime through multi-ion doping and core-shell structural design, are presented. The obtained internal PLQY can reach up to 50.1% in cyclohexane and 9.2% in water under excitation at 980 nm. Inspired by the above results, a fast NIR-II fluorescence lifetime imaging of whole-body vascular in mice is successfully performed by using the homebuilt fluorescence lifetime imaging system, which reveals a murine abdominal capillary network with low background. A further demonstration of fluorescence lifetime multiplex imaging is carried out in molecular imaging of atherosclerosis cells and different organs in vivo through NPs conjugating with specific peptides and different injection modalities, respectively. These results demonstrate that the high PLQY NPs combined with the homebuilt fluorescence lifetime imaging system can realize a fast and high signal-to-noise fluorescence lifetime imaging; thus, opening a road for multiplex molecular imaging of atherosclerosis.


Assuntos
Aterosclerose , Elementos da Série dos Lantanídeos , Nanopartículas , Animais , Camundongos , Elementos da Série dos Lantanídeos/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Imagem Óptica , Nanopartículas/química
3.
Inorg Chem ; 62(28): 11112-11120, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37395531

RESUMO

Recent decades have witnessed a major development in broadband near-infrared (NIR)-emitting phosphors because of their potential applications in real-time nondestructive examination. These applications require the emission spectra of phosphors to be as broad as possible for efficient performance. Therefore, a blue-light excited LiInF4: Cr3+ phosphor with a NIR emission covering 700-1400 nm is successfully synthesized. Under 470 nm excitation, it shows broadband emission peaked at 980 nm with the full-width at half maximum of 210 nm. The structure and crystal field environment are investigated in detail, and the LiInF4: Cr3+ possesses a weak crystal field strength and strong electron-phonon coupling. An efficient NIR phosphor-converted light-emitting diode (pc-LED) is fabricated by the prepared LiInF4: Cr3+ phosphor and commercial blue diode chip, generating a NIR radiant flux of 5.54 mW at 150 mA drive current. Finally, the NIR pc-LED is successfully applied to identify the blood vessel distribution of the hand. This work suggests the potential of LiInF4: Cr3+ phosphor in applications.

4.
Neurochem Res ; 46(5): 1141-1150, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33534059

RESUMO

Propofol is one of the most common intravenous anesthetics which may cause neuronal cell death in young mice. HOX transcript antisense RNA (HOTAIR) was abnormally expressed in neurodegenerative diseases. However, the effect of HOTAIR on propofol-induced pyroptosis of neurons and related mechanisms are still unknown. In this study, propofol treatment significantly reduced neuronal the viability of neurons, and promoted the expression of inflammation-related factors. Propofol treatment also promoted neuron death and neuronal pyroptosis. All the above effects might be related to the propofol-induced overexpression of HOTAIR. Interestingly, knockdown of HOTAIR by shRNA (sh-HOTAIR) significantly inhibited neuronal pyroptosis, but increased neuronal viability. Further analysis showed that HOTAIR and Nod-like receptor protein1 (NLRP1) were the targets of miR-455-3p, respectively. Notably, propofol treatment decreased the level of miR-455-3p, while increased the level of NLRP1. In addition, sh-HOTAIR increased the level of miR-455-3p, which further inhibited the expression of NLRP1 and the activation of NLRP1 inflammasome, thereby inhibiting neuronal pyroptosis. More importantly, NLRP1 overexpression decreased neuronal viability, and reactivated NLRP1 inflammasome, thus reversing the inhibitory effect of sh-HOTAIR on pyroptosis. Our findings indicated that HOTAIR inhibited propofol-induced pyroptosis of neurons by regulating miR-455-3p/NLRP1 axis, indicating that HOTAIR may be a potential therapeutic target for propofol-induced neurotoxicity.


Assuntos
MicroRNAs/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Propofol/farmacologia , Piroptose/fisiologia , RNA Longo não Codificante/metabolismo , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Feminino , Técnicas de Silenciamento de Genes , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Masculino , Neurônios/efeitos dos fármacos , Piroptose/efeitos dos fármacos , RNA Longo não Codificante/genética , RNA Interferente Pequeno/farmacologia , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
5.
BMC Pregnancy Childbirth ; 21(1): 713, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702205

RESUMO

BACKGROUND: Antenatal depression has become a common and serious problem, significantly affecting maternal and fetal health. However, evaluation and intervention methods for pregnant women in obstetric clinics are inadequate. This study aimed to determine the prevalence of and risk factors for depression among all pregnant women at their first attending antenatal care in the obstetrics clinic, a comprehensive teaching hospital, southwest of China. METHODS: From June to December 2019, 5780 pregnant women completed online psychological assessments, and data from 5728 of the women were analyzed. The women were categorized into two groups according to the presence or absence of depression. Depression was assessed by the Patient Health Questionnaire-9 (PHQ-9), with a cutoff point of 10 for depression. Anxiety and somatic symptoms were measured by the Generalized Anxiety Disorder-7 (GAD-7) and Patient Health Questionnaire-15 (PHQ-15), respectively. Univariate analysis and binary logistic regression analysis were used to determine the association among antenatal depression, anxiety, somatic symptoms and participants' characteristics. RESULTS: The prevalence of antenatal depression among all the pregnant women at their first attending antenatal care was 16.3%, higher in the first trimester (18.1%). Anxiety symptoms (Mild anxiety AOR = 2.937; 95% CI: 2.448-3.524) and somatic symptoms (Mild somatic symptoms AOR = 3.938; 95% CI: 2.888-3.368) were major risk factors for antenatal depression among women and the risk increased more with the anxiety level or somatic symptoms level. Gestational weeks (second trimester AOR = 0.611; 95% CI: 0.483-0.773; third trimester AOR = 0.337; 95% CI: 0.228-0.498) and urban residence (AOR = 0.786; 95% CI: 0.652-0.947) were protective factors for antenatal depression among women. CONCLUSIONS: About one in six pregnant women would experience depression, and special attention should be paid to some risk factors (i.e., early pregnancy, anxiety symptoms, somatic symptoms, rural residence). Online psychological assessments might be a time-saving and convenient screening method for pregnant women in obstetric clinics.


Assuntos
Depressão/epidemiologia , Complicações na Gravidez/epidemiologia , Gestantes/psicologia , Cuidado Pré-Natal/psicologia , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Hospitais de Ensino , Humanos , Questionário de Saúde do Paciente , Gravidez , Prevalência , Fatores de Risco
6.
Exp Mol Pathol ; 115: 104444, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32335082

RESUMO

Intestinal ischemia-reperfusion (I/R) is a life-threatening condition associated with high morbidity and mortality. Dexmedetomidine (DEX), an agonist of α2-adrenoceptor with sedation and analgesia effect, has recently been identified with protective function against I/R injury in multiple organs. However, the mechanism underlying the beneficial effect of DEX on intestine after I/R injury remained poorly understood. In the present study, using in both in vitro and in vivo models, we found that intestinal I/R injury was associated with the activation of p38 MAPK cascade, while DEX was capable of deactivating p38 MAPK and thus protect intestinal cells from apoptosis by inhibiting p38 MAPK-mediated mitochondrial depolarization and cytochrome c (Cyto C) release. Moreover, through inhibiting p38 MAPK activity, the downstream production of pro-inflammatory cytokines-regulated by NF-κB was also suppressed by DEX treatment, leading to the resolution of I/R-induced inflammation in intestine. In general, our study provided evidence that DEX protected intestine from I/R injury by inhibiting p38 MAPK-mediated mitochondrial apoptosis and inflammatory response.


Assuntos
Dexmedetomidina/uso terapêutico , Intestinos/patologia , Sistema de Sinalização das MAP Quinases , Substâncias Protetoras/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/enzimologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células CACO-2 , Dexmedetomidina/farmacologia , Glucose/deficiência , Humanos , Inflamação/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Oxigênio , Substâncias Protetoras/farmacologia , Ratos Wistar , Traumatismo por Reperfusão/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
7.
Inorg Chem ; 58(9): 6376-6387, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31012577

RESUMO

Cation-substitution-induced controllable luminescence tuning could efficiently optimize and improve the luminescence performances of novel phosphor materials for realizing high-quality lighting. As important members of the orthophosphate family, ABPO4 (A = alkali metal Li, Na, K, Rb, Cs; B = alkali earth metal Mg, Ca, Sr, Ba) offers an abundant cation lattice environment for rare earth ions. Herein, we successfully prepared a broad-band red-emitting CsMgPO4:Eu2+ phosphor with an emission peak at 628 nm (fwhm = 118 nm). A series of cation-substitution strategies are designed to adjust and enhance its luminescence performances. The corresponding mechanisms are also investigated and proposed reasonably. A charge-compensation strategy of [Eu2+-Si4+] → [Cs+-P5+] could dramatically enhance the quenching concentration from 0.04 to 0.30, which is attributed to the decrease of Eu3+. Two cation-substitution strategies of larger Ba2+ (Sr2+) ions for Mg2+ ions could achieve superior emission adjustment of Eu2+ ions from the red to blue (yellow) region due to local lattice distortion. Interestingly, a consecutive emission adjustment from the red to blue region by simply changing the annealed temperature is reported for the first time, and the possible emission tuning mechanism is revealed based on a local lattice-strain control. This study could serve as a guide in developing Eu2+-activated ABPO4 phosphors with improving luminescence performance and controllable luminescence adjustment based on charge compensation and lattice-strain control through various cation substitutions.

8.
Inorg Chem ; 57(15): 9251-9259, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-29995392

RESUMO

In the pursuit of high-quality W-LED lighting, the precise control of emission color of phosphor materials is indispensable. Herein we report a series of single-composition Bi3+-doped LiCa3MgV3O12 garnet-structure phosphors, whose emission colors under n-UV excitation could be tuned from bluish green (480 nm) to yellow (562 nm) on the basis of local lattice distortion and VO43- → Bi3+ energy transfer. Furthermore, full-color luminescence tuning from bluish green to orangish red across the warm white light region was successfully achieved by designing VO43- → Bi3+ → Eu3+ energy transfers. More interestingly, the thermal stabilities of as-prepared samples were gradually enhanced through designing VO43-/Bi3+ → Eu3+ energy transfers. This work provides a new perspective for color tuning originating from simultaneous local lattice distortion and multiple energy transfers.

9.
Mikrochim Acta ; 185(11): 519, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30361934

RESUMO

CdTe quantum dots (QDs) were integrated with polyethyleneimine-coated carbon dots (PEI-CDs) to form a dually emitting probe for heparin. The red fluorescence of the CdTe QDs is quenched by the PEI-CDs due to electrostatic interactions. In the presence of heparin, the blue fluorescence of PEI-CDs remains unaffected, while its quenching effect on the fluorescence of CdTe QDs is strongly reduced. A ratiometric fluorometric assay was worked out. The ratio of the fluorescences at 595 and 436 nm serves as the analytical signal. Response is linear in the concentration range of 50-600 ng·mL-1 (0.1-1.2 U·mL-1) of heparin. The limit of detection is 20 ng·mL-1 (0.04 U·mL-1). This makes the method a valuable tool for heparin monitoring during postoperative and long-term care. This assay is relatively free from the interference by other analogues which commonly co-exist with heparin in samples, and it is more robust than single-wavelength based assays. Graphical abstract In the presence of heparin, the fluorescence of polyethyleneimine-coated carbon dots (PEI-CDs) at 436 nm remains unaffected, while its quenching effect on the fluorescence of CdTe at 595 nm is strongly reduced.


Assuntos
Compostos de Cádmio/química , Carbono/química , Fluorometria/métodos , Heparina/análise , Polietilenoimina/química , Pontos Quânticos/química , Telúrio/química , Heparina/sangue , Humanos , Concentração de Íons de Hidrogênio , Fatores de Tempo
10.
NMR Biomed ; 30(10)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28665041

RESUMO

The purpose of this study was to measure and model the diffusion time dependence of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) derived from conventional prostate diffusion-weighted imaging methods as used in recommended multiparametric MRI protocols. Diffusion tensor imaging (DTI) was performed at 9.4 T with three radical prostatectomy specimens, with diffusion times in the range 10-120 ms and b-values 0-3000 s/mm2 . ADC and FA were calculated from DTI measurements at b-values of 800 and 1600 s/mm2 . Independently, a two-component model (restricted isotropic plus Gaussian anisotropic) was used to synthesize DTI data, from which ADC and FA were predicted and compared with the measured values. Measured ADC and FA exhibited a diffusion time dependence, which was closely predicted by the two-component model. ADC decreased by about 0.10-0.15 µm2 /ms as diffusion time increased from 10 to 120 ms. FA increased with diffusion time at b-values of 800 and 1600 s/mm2 but was predicted to be independent of diffusion time at b = 3000 s/mm2 . Both ADC and FA exhibited diffusion time dependence that could be modeled as two unmixed water pools - one having isotropic restricted dynamics, and the other unrestricted anisotropic dynamics. These results highlight the importance of considering and reporting diffusion times in conventional ADC and FA calculations and protocol recommendations, and inform the development of improved diffusion methods for prostate cancer imaging.


Assuntos
Anisotropia , Imagem de Difusão por Ressonância Magnética/métodos , Modelos Biológicos , Próstata/anatomia & histologia , Difusão , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
11.
Inorg Chem ; 56(11): 6131-6140, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28481110

RESUMO

A series of Eu3+/Tb3+/Mn2+-ion-doped Ca19Ce(PO4)14 (CCPO) phosphors have been prepared via the conventional high-temperature solid-state reaction process. Under UV radiation, the CCPO host presents a broad blue emission band from Ce3+ ions, which are generated during the preparation process because of the formation of deficiency. The Eu3+-doped CCPO phosphors can exhibit magenta to red-orange emission as a result of the abnormal coexistence of Ce3+/Ce4+/Eu3+ and the metal-metal charge-transfer (MMCT) effect between Ce3+ and Eu3+. When Tb3+/Mn2+ are doped into the hosts, the samples excited with 300 nm UV light present multicolor emissions due to energy transfer (ET) from the host (Ce3+) to the activators with increasing activator concentrations. The emitting colors of CCPO:Tb3+ phosphors can be tuned from blue to green, and the CCPO:Mn2+ phosphors can emit red light. The ET mechanism from the host (Ce3+) to Tb3+/Mn2+ is demonstrated to be a dipole-quadrapole interaction for Ce3+ → Tb3+ and an exchange interaction for Ce3+ → Mn2+ in CCPO:Tb3+/Mn2+. Abundant emission colors containing white emission were obtained in the Tb3+- and Mn2+-codoped CCPO phosphors through control of the levels of doped Tb3+ and Mn2+ ions. The white-emitted CCPO:Tb3+/Mn2+ phosphor exhibited excellent thermal stability. The photoluminescence properties have shown that these materials might have potential for UV-pumped white-light-emitting diodes.

12.
Inorg Chem ; 56(19): 11900-11910, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28926231

RESUMO

Narrow band red-emitting A2GeF6:Mn4+ (A = Na, K, Rb, Cs) phosphors were prepared through a two-step precipitation-cation exchange route using a K2MnF6 precursor as the Mn4+ source. The phase purity, morphology, and constituent were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectric spectroscopy (XPS), and electron paramagnetic resonance (EPR) examination. Optical properties were investigated by photoluminescence spectra (PL and PLE) and high-resolution PL. A temperature-dependent PL examination was performed to investigate the electron-phonon coupling emission mechanism of Mn4+ in these alkali fluorogermanates. The PL data show that both ordered distribution and appropriate distance between Mn4+ ions are propitious for enhancement of the emission intensity. A resonance emission enhancement (REE) mechanism has been proposed to explain the intensity increment among these products. These phosphors present bright red emission under blue light (467 nm) illumination, among which Cs2GeF6:0.03Mn4+ exhibits the most excellent optical properties with a quantum yield (QY) of 93%. A WLED (white light-emitting diode) fabricated with blend of commercial YAG:Ce3+ and this phosphor emits intense warm white light with low color temperature (CCT = 3385 K) and high color rendering index (Ra = 90.5), implying its potential application as red phosphor in WLEDs.

13.
NMR Biomed ; 29(5): 660-71, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26999065

RESUMO

This study compares the theoretical information content of single- and multi-compartment models of diffusion-weighted signal attenuation in prostate tissue. Diffusion-weighted imaging (DWI) was performed at 9.4 T with multiple diffusion times and an extended range of b values in four whole formalin-fixed prostates. Ten models, including different combinations of isotropic, anisotropic and restricted components, were tested. Models were ranked using the Akaike information criterion. In all four prostates, two-component models, comprising an anisotropic Gaussian component and an isotropic restricted component, ranked highest in the majority of voxels. Single-component models, whether isotropic (apparent diffusion coefficient, ADC) or anisotropic (diffusion tensor imaging, DTI), consistently ranked lower than multi-component models. Model ranking trends were independent of voxel size and maximum b value in the range tested (1.6-16 mm(3) and 3000-10,000 s/mm(2)). This study characterizes the two major water components previously identified by biexponential models and shows that models incorporating both anisotropic and restricted components provide more information-rich descriptions of DWI signals in prostate tissue than single- or multi-component anisotropic models and models that do not account for restricted diffusion.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Modelos Anatômicos , Próstata/anatomia & histologia , Processamento de Sinais Assistido por Computador , Fixação de Tecidos , Humanos , Masculino , Pessoa de Meia-Idade
14.
Inorg Chem ; 55(15): 7593-604, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27415966

RESUMO

A series of Ce(3+), Tb(3+), Eu(3+) doped Ba2Y2(PO4)2(SiO4) (BYSPO) phosphors were synthesized via the high-temperature solid-state reaction route. X-ray diffraction, high-resolution transmission electron microscopy, Fourier transform infrared, solid-state NMR, photoluminescence (PL) including temperature-dependent PL, and fluorescent decay measurements were conducted to characterize and analyze as-prepared samples. BYSPO was obtained by the substitution of Y+SiO4 for Ba+PO4 in Ba3Y(PO4)3 (BYPO). The red shift of PL emission from 375 to 401 nm occurs by comparing BYSPO:0.14Ce(3+) with BYPO:0.14Ce(3+) under 323 nm UV excitation. More importantly, the excitation edge can be extended from 350 to 400 nm, which makes it be excited by UV/n-UV chips (330-410 nm). Tunable emission color from blue to green can be observed under 365 nm UV excitation based on the energy transfer from Ce(3+) to Tb(3+) ions after codoping Tb(3+) into BYSPO:0.14Ce(3+). Moreover, energy transfer from Tb(3+) to Eu(3+) ions also can be found in BYSPO:Tb(3+),Eu(3+) phosphors, resulting in the tunable color from green to orange red upon 377 nm UV excitation. Energy transfer properties were demonstrated by overlap of excitation spectra, variations of emission spectra, and decay times. In addition, energy transfer mechanisms from Ce(3+) to Tb(3+) and Tb(3+) to Eu(3+) in BYSPO were also discussed in detail. Quantum yields and CIE chromatic coordinates were also presented. Generally, the results suggest their potential applications in UV/n-UV pumped LEDs.

15.
Chemistry ; 21(39): 13539-43, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26251196

RESUMO

A reversible wetting/dewetting procedure is reported for an open-cage fullerene with an 18-membered orifice. In a homogeneous mixture of H2O/EtOH/CHCl3, water was encapsulated into the cavity of the open-cage compound quantitatively at 80 °C. Addition of aqueous hydrogen fluoride into the water-encapsulated complex removed the encapsulated water completely at room temperature. H-bonding between the trapped water and fluoride is shown to play a key role for the water release process.

16.
J Org Chem ; 80(8): 3957-64, 2015 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-25781177

RESUMO

Tetrahydro[60]fullerene epoxides C60(O)Ar(n)(NR2)(4-n), n = 1, 2, have been prepared by treating 1,4-adducts C60(OH)Ph and C60(Tol)2 with cyclic secondary amines. The epoxy moieties in these mixed tetrahydro[60]fullerene epoxides were hydrolyzed into the corresponding diol derivatives, which were further oxidized into diketone open-cage fullerenes with a 10-membered orifice. A few other reactions also showed that the present tetrahydro[60]fullerene epoxides with both amino and aryl addends exhibit improved chemical reactivity over the tetraamino[60]fullerene epoxide without any aryl group.

17.
J Org Chem ; 79(12): 5794-8, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24865369

RESUMO

Unlike the extensively studied perfluoroalkyl fullerene adducts, perfluorophenyl fullerene adducts are quite difficult to prepare by known methods. Trispentafluorophenylborane was found to react with fullerene epoxide to form the 1,2-perfluorophenylfullerenol. The method can be applied to both the simple epoxide C60(O) and fullerene multiadducts containing an epoxide moiety. Single crystal X-ray structure analysis confirmed the addition of the pentafluorophenyl group.

18.
Methods Mol Biol ; 2644: 15-33, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37142913

RESUMO

The MTT assay is extensively used, most often to infer a measure of cytotoxicity of treatments to cells. As with any assay though, there are a number of limitations. The method described here is designed with consideration of how the MTT assay fundamentally works to account for, or at least identify, confounding factors in measurements. It also provides a decision-making framework to best interpret and complement the MTT assay to apply it as either a measure of metabolic activity or cell viability.


Assuntos
Projetos de Pesquisa , Sais de Tetrazólio/metabolismo , Sobrevivência Celular
19.
Urban Stud ; 60(9): 1730-1749, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37416835

RESUMO

The state-society relationship in neighbourhood governance has been a focal topic in the urban governance literature, though the existing scholarship was primarily drawn from non-crisis situations. Adopting a mixed-methods approach, this study investigates the intricate state-society dynamics manifested at the neighbourhood scale as state and societal actors collaborated during China's COVID-19 responses. Our study reveals a pattern of collaborative rather than confrontational dynamics between resident committees and other stakeholders during pandemic responses, which reflects the emergence of a constructed order of neighbourhood co-governance in urban China. Previous community-building reforms consolidated the political legitimacy, power and capacity of resident committees, which were empowered to play a critical coordinating role in bridging hierarchical state mobilisation and horizontal stakeholders in the collaborative pandemic responses. These findings contribute to a more nuanced understanding of neighbourhood co-governance in the international literature and provide lessons for resilience governance from a comparative lens.

20.
Neurosci Lett ; 807: 137259, 2023 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-37075883

RESUMO

Postoperative cognitive dysfunction (POCD) is common in aged patients after major surgery and is associated with increased risk of long-term morbidity and mortality. However, the underlying mechanism remains largely unknown and the clinical management of POCD is still controversial. Stellate ganglion block (SGB) is a clinical treatment for nerve injuries and circulatory issues. Recent evidence has identified the benefits of SGB in promoting learning and memory. We thus hypothesize that SGB could be effective in improving cognitive function after surgery. In present study, we established POCD model in aged rats via partial liver resection surgery. We found that the development of POCD was associated with the activation of toll-like receptor 4/nuclear factor kapa-B (TLR4/NF-κB) signaling pathway in the microglia in dorsal hippocampus, which induced the production of pro-inflammatory mediators (TNF-α, IL-1ß, IL-6) and promoted neuroinflammation. More importantly, we showed evidence that preoperative treatment with SGB could inhibit microglial activation, suppress TLR4/NF-κB-mediated neuroinflammation and effectively attenuate cognitive decline after the surgery. Our study suggested that SGB may serve as a novel treatment to prevent POCD in elderly patients. As SGB is safe procedure widely used in clinic, our findings can be easily translated into clinical practice and benefit more patients.


Assuntos
Disfunção Cognitiva , Complicações Cognitivas Pós-Operatórias , Ratos , Animais , NF-kappa B/metabolismo , Complicações Cognitivas Pós-Operatórias/prevenção & controle , Complicações Cognitivas Pós-Operatórias/metabolismo , Doenças Neuroinflamatórias , Receptor 4 Toll-Like/metabolismo , Gânglio Estrelado/metabolismo , Transdução de Sinais , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/prevenção & controle , Disfunção Cognitiva/tratamento farmacológico , Microglia/metabolismo
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